1
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Dowker SR, Downey ML, Majhail NK, Scott IG, Mathisson J, Rizk D, Trumpower B, Yake D, Williams M, Coulter‐Thompson EI, Brent CM, Smith GC, Swor R, Berger DA, Rooney DM, Neumar RW, Friedman CP, Cooke JM, Missel AL. Early intranasal medication administration in out-of-hospital cardiac arrest: Two randomized simulation trials. J Am Coll Emerg Physicians Open 2024; 5:e13100. [PMID: 38260004 PMCID: PMC10800291 DOI: 10.1002/emp2.13100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 12/13/2023] [Accepted: 12/18/2023] [Indexed: 01/24/2024] Open
Abstract
Objective Intranasal medications have been proposed as adjuncts to out-of-hospital cardiac arrest (OHCA) care. We sought to quantify the effects of intranasal medication administration (INMA) in OHCA workflows. Methods We conducted separate randomized OHCA simulation trials with lay rescuers (LRs) and first responders (FRs). Participants were randomized to groups performing hands-only cardiopulmonary resuscitation (CPR)/automated external defibrillator with or without INMA during the second analysis phase. Time to compression following the second shock (CPR2) was the primary outcome and compression quality (chest compression rate (CCR) and fraction (CCF)) was the secondary outcome. We fit linear regression models adjusted for CPR training in the LR group and service years in the FR group. Results Among LRs, INMA was associated with a significant increase in CPR2 (mean diff. 44.1 s, 95% CI: 14.9, 73.3), which persisted after adjustment (p = 0.005). We observed a significant decrease in CCR (INMA 95.1 compressions per min (cpm) vs control 104.2 cpm, mean diff. -9.1 cpm, 95% CI -16.6, -1.6) and CCF (INMA 62.4% vs control 69.8%, mean diff. -7.5%, 95% CI -12.0, -2.9). Among FRs, we found no significant CPR2 delays (mean diff. -2.1 s, 95% CI -15.9, 11.7), which persisted after adjustment (p = 0.704), or difference in quality (CCR INMA 115.5 cpm vs control 120.8 cpm, mean diff. -5.3 cpm, 95% CI -12.6, 2.0; CCF INMA 79.6% vs control 81.2% mean diff. -1.6%, 95% CI -7.4, 4.3%). Conclusions INMA in LR resuscitation was associated with diminished resuscitation performance. INMA by FR did not impede key times or quality.
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Affiliation(s)
- Stephen R. Dowker
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Madison L. Downey
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Noor K. Majhail
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Isabella G. Scott
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Jonah Mathisson
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Daniel Rizk
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Brad Trumpower
- Department of Internal MedicineDivision of Cardiovascular MedicineUniversity of Michigan Medical School, 2139 Cardiovascular CenterAnn ArborMichiganUSA
| | - Debra Yake
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Michelle Williams
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Emilee I. Coulter‐Thompson
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
- Center for Bioethics and Social Sciences in Medicine, University of MichiganAnn ArborMichiganUSA
| | - Christine M. Brent
- Department of Emergency MedicineUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Graham C. Smith
- Department of Emergency MedicineUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Robert Swor
- Department of Emergency MedicineCorewell East William Beaumont University HospitalRoyal OakMichiganUSA
- Department of Emergency MedicineOakland University William Beaumont School of MedicineRochesterMichiganUSA
| | - David A. Berger
- Department of Emergency MedicineCorewell East William Beaumont University HospitalRoyal OakMichiganUSA
- Department of Emergency MedicineOakland University William Beaumont School of MedicineRochesterMichiganUSA
| | - Deborah M. Rooney
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Robert W. Neumar
- Department of Emergency MedicineUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
- Max Harry Weil Institute for Critical Care Research and Innovation, University of MichiganAnn ArborMichiganUSA
| | - Charles P. Friedman
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - James M. Cooke
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
- Department of Family MedicineUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
| | - Amanda L. Missel
- Department of Learning Health SciencesUniversity of Michigan Medical SchoolAnn ArborMichiganUSA
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2
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Salhi RA, Iyengar S, da Silva Bhatia B, Smith GC, Heisler M. How do current police practices impact trauma care in the prehospital setting? A scoping review. J Am Coll Emerg Physicians Open 2023; 4:e12974. [PMID: 37229183 PMCID: PMC10204184 DOI: 10.1002/emp2.12974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 04/08/2023] [Accepted: 04/27/2023] [Indexed: 05/27/2023] Open
Abstract
Objective In the United States, police are often important co-responders to 911 calls with emergency medical services for medical emergencies. To date, there remains a lack of a comprehensive understanding of the mechanisms by which police response modifies time to in-hospital medical care for traumatically injured patients. Further, it remains unclear if differentials exist within or between communities. A scoping review was performed to identify studies evaluating prehospital transport of traumatically injured patients and the role or impact of police involvement. Methods PubMed, SCOPUS, and Criminal Justice Abstracts databases were utilized to identify articles. English-language, US-based, peer-reviewed articles published on or prior to March 30, 2022 were eligible for inclusion. Results Of 19,437 articles initially identified, 70 articles were selected for full review and 17 for final inclusion. Key findings included (1) current law enforcement practices involving scene clearance introduce the potential for delayed patient transport but to date there is little research quantifying delays; (2) police transport protocols may decrease transport times; and (3) there are no studies examining the potential impact of scene clearance practices at the patient or community level. Conclusions Our results highlight that police are often the first on scene when responding to traumatic injuries and have an active role via scene clearance or, in some systems, patient transport. Despite the significant potential for impact on patient well-being, there remains a paucity of data examining and driving current practices.
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Affiliation(s)
- Rama A. Salhi
- Department of Emergency MedicineMassachusetts General HospitalBostonMassachusettsUSA
| | - Sonia Iyengar
- University of Michigan Medical SchoolAnn ArborMichiganUSA
| | | | - Graham C. Smith
- Department of Emergency MedicineUniversity of MichiganAnn ArborMichiganUSA
- Washtenaw/Livingston Medical Control AuthorityAnn ArborMichiganUSA
| | - Michele Heisler
- Department of Internal MedicineUniversity of MichiganAnn ArborMichiganUSA
- Institute for Healthcare Policy and InnovationUniversity of MichiganAnn ArborMichiganUSA
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3
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Kao RR, Smith GC, Walker M. Infectious disease modelling to inform policy. REV SCI TECH OIE 2023; 42:173-179. [PMID: 37232307 DOI: 10.20506/rst.42.3360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
With modelling becoming increasingly important in helping to inform decisions about animal diseases, it is essential that the process be optimised to gain the maximum benefit for the decision-maker. Here, the authors set out ten steps that can improve this process for all concerned. Four steps describe initialisation to ensure that the question, answer and timescale are defined; two steps describe the modelling process and quality assurance; and four steps describe the reporting stage. The authors believe that this greater emphasis at the beginning and end of a modelling project will increase the relevance of the work and understanding of the results, and thus contribute towards better decision-making.
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4
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Turer RW, Smith GC, Mehkri Do F, Chou A, Fowler R, Idris AH, Lehmann CU, McDonald SA. Improving Emergency Medical Services Information Exchange: Methods for Automating Entity Resolution. Stud Health Technol Inform 2022; 291:17-26. [PMID: 35593755 DOI: 10.3233/shti220004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The 21st century has seen an enormous growth in emergency medical services (EMS) information technology systems, with corresponding accumulation of large volumes of data. Despite this growth, integration efforts between EMS-based systems and electronic health records, and public-sector databases have been limited due to inconsistent data structure, data missingness, and policy and regulatory obstacles. Efforts to integrate EMS systems have benefited from the evolving science of entity resolution and record linkage. In this chapter, we present the history and fundamentals of record linkage techniques, an overview of past uses of this technology in EMS, and a look into the future of record linkage techniques for integrating EMS data systems including the use of machine learning-based techniques.
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Affiliation(s)
- Robert W Turer
- University of Texas Southwestern Medical Center, Department of Emergency Medicine. Dallas, TX, USA.,University of Texas Southwestern Medical Center, Clinical Informatics Center. Dallas, TX, USA
| | - Graham C Smith
- University of Michigan Medical School, Department of Emergency Medicine. Ann Arbor, MI, USA
| | - Faroukh Mehkri Do
- University of Texas Southwestern Medical Center, Department of Emergency Medicine. Dallas, TX, USA
| | - Andrew Chou
- University of Texas Southwestern Medical Center, Department of Emergency Medicine. Dallas, TX, USA
| | - Ray Fowler
- University of Texas Southwestern Medical Center, Department of Emergency Medicine. Dallas, TX, USA
| | - Ahamed H Idris
- University of Texas Southwestern Medical Center, Department of Emergency Medicine. Dallas, TX, USA
| | - Christoph U Lehmann
- University of Texas Southwestern Medical Center, Clinical Informatics Center. Dallas, TX, USA.,University of Texas Southwestern Medical Center, Department of Pediatrics. Dallas, TX, USA
| | - Samuel A McDonald
- University of Texas Southwestern Medical Center, Department of Emergency Medicine. Dallas, TX, USA.,University of Texas Southwestern Medical Center, Clinical Informatics Center. Dallas, TX, USA
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5
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Rossi G, Crispell J, Brough T, Lycett SJ, White PCL, Allen A, Ellis RJ, Gordon SV, Harwood R, Palkopoulou E, Presho EL, Skuce R, Smith GC, Kao RR. Phylodynamic analysis of an emergent
Mycobacterium bovis
outbreak in an area with no previously known wildlife infections. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.14046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gianluigi Rossi
- Roslin Institute and R(D)SVS University of Edinburgh Edinburgh UK
| | - Joseph Crispell
- School of Veterinary Medicine University College Dublin Dublin Ireland
| | - Tanis Brough
- Advice Services Team Service Delivery Directorate APHA Penrith UK
| | | | | | - Adrian Allen
- Bacteriology Branch Veterinary Sciences Division Agri‐food and Biosciences Institute Belfast UK
| | - Richard J. Ellis
- Surveillance and Laboratory Services Department APHA Addlestone UK
| | - Stephen V. Gordon
- School of Veterinary Medicine University College Dublin Dublin Ireland
- Conway Institute University College Dublin Dublin Ireland
| | | | | | - Eleanor L. Presho
- Bacteriology Branch Veterinary Sciences Division Agri‐food and Biosciences Institute Belfast UK
| | - Robin Skuce
- Bacteriology Branch Veterinary Sciences Division Agri‐food and Biosciences Institute Belfast UK
| | | | - Rowland R. Kao
- Roslin Institute and R(D)SVS University of Edinburgh Edinburgh UK
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6
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Downs SH, Ashfield S, Arnold M, Roberts T, Prosser A, Robertson A, Frost S, Harris K, Avigad R, Smith GC. Detection of a local Mycobacterium bovis reservoir using cattle surveillance data. Transbound Emerg Dis 2021; 69:e104-e118. [PMID: 34333857 PMCID: PMC9544780 DOI: 10.1111/tbed.14272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/20/2021] [Accepted: 07/28/2021] [Indexed: 11/29/2022]
Abstract
The incidence of bovine tuberculosis (TB, caused by Mycobacterium bovis) in cattle has been associated with TB in badgers (Meles meles) in parts of England. The aim was to identify badger‐associated M. bovis reservoirs in the Edge Area, between the High‐ and Low‐Risk Areas for cattle TB. Data from badger TB surveys were sparse. Therefore, a definition for a local M. bovis reservoir potentially shared by cattle and badgers was developed using cattle TB surveillance data. The performance of the definition was estimated through Latent Class Analysis using badger TB survey data. Spatial units (25 km2) in the Edge Area were classified as having a reservoir if they had (i) at least one TB incident in at least three of the previous 7 years, (ii) at least one TB incident in a cattle herd confirmed by post‐mortem tests as due to M. bovis infection and not attributable to cattle movements in the previous 2 years and (iii) more confirmed TB incidents than un‐confirmed in the previous 2 years. Approximately 20% of the Edge Area was classified as having a local M. bovis reservoir using the cattle‐based definition. Assuming 15% TB prevalence in Edge Area badgers, sensitivity for the local M. bovis reservoir definition varied from 25.7% [95% credible interval (CrI): 10.7%–85.1%] to 64.8% (95% CrI: 48.1%–88.0%). Specificity was 91.9% (CrI: 83.6%–97.4%). Over 90% of the local reservoir was in stable endemic TB areas identified through previous work and its spatial distribution was largely consistent with local veterinary knowledge. Uncertainty in the reservoir spatial distribution was explored through its recalculation in spatial units shifted in different directions. We recommend that the definition is re‐evaluated as further data on badger infection with M. bovis become available.
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Affiliation(s)
- Sara H Downs
- Department of Epidemiological Sciences, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Stuart Ashfield
- Department of Epidemiological Sciences, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Mark Arnold
- Department of Epidemiological Sciences, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Tony Roberts
- Veterinary Advice Services, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Alison Prosser
- Department of Epidemiological Sciences, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Andy Robertson
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9FE, UK.,National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, UK
| | - Susanne Frost
- Veterinary Advice Services, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Kate Harris
- Department of Epidemiological Sciences, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Rachelle Avigad
- Department of Epidemiological Sciences, Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK
| | - Graham C Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, York, UK
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7
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Kim JS, Marlais M, Balasubramanian R, Muorah M, Inward C, Smith GC, Reynolds BC, Yadav P, Morgan H, Shenoy M, Tse Y, Hussain F, Grylls S, Kessaris N, Sinha MD, Marks SD. UK national study of barriers to renal transplantation in children. Arch Dis Child 2021; 106:384-386. [PMID: 32241783 DOI: 10.1136/archdischild-2019-318272] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 03/19/2020] [Indexed: 11/04/2022]
Abstract
AIMS To investigate access to paediatric renal transplantation and examine potential barriers within the process. METHODS Cross-sectional, multicentre, observational study where paediatric nephrology centres in the UK were requested to provide data on transplantation plans for all children (<18 years) with end-stage kidney disease (ESKD). RESULTS 308 children with ESKD were included in this study from 12 out of 13 UK paediatric nephrology centres. 139 (45%) were being prepared for living donor transplantation and 82 (27%) were listed for deceased donor transplantation. The most common cited factors delaying transplantation from occurring in children were disease factors (36%), donor availability (27%) and size of the child (20%). Psychosocial factors were listed as a barrier in 19% of children. CONCLUSIONS In this study we have documented the main barriers to renal transplantation in children. Some identified factors may be modifiable through local or national intervention, including donor availability and patient psychosocial factors.
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Affiliation(s)
- Ji Soo Kim
- Paediatric Nephrology, Great Ormond Street Hospital For Children NHS Foundation Trust, London, UK .,Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Matko Marlais
- Paediatric Nephrology, Great Ormond Street Hospital For Children NHS Foundation Trust, London, UK.,Great Ormond Street Institute of Child Health, University College London, London, UK
| | | | - Mordi Muorah
- Paediatric Nephrology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK
| | - Carol Inward
- Paediatric Nephrology, Bristol Royal Hospital for Children, Bristol, UK
| | - Graham C Smith
- Paediatric Nephrology, Children's Hospital for Wales, Cardiff, UK
| | - Ben C Reynolds
- Paediatric Renal Unit, Royal Hospital for Children Glasgow, Glasgow, UK
| | - Pallavi Yadav
- Paediatric Nephrology, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Henry Morgan
- Paediatric Nephrology, Alder Hey Children's NHS Foundation Trust, Liverpool, UK
| | - Mohan Shenoy
- Paediatric Nephrology, Royal Manchester Children's Hospital, Manchester, UK
| | - Yincent Tse
- Paediatric Nephrology, Great North Children's Hospital, Newcastle Upon Tyne, UK
| | - Farida Hussain
- Paediatric Nephrology, Nottingham Children's Hospital, Nottingham, UK
| | - Sarah Grylls
- Paediatric Nephrology, Southampton Children's Hospital, Southampton, UK
| | - Nicos Kessaris
- Paediatric Nephrology, Great Ormond Street Hospital For Children NHS Foundation Trust, London, UK.,Transplantation, Evelina London Children's Hospital, London, UK
| | - Manish D Sinha
- Paediatric Nephrology, Evelina London Children's Hospital, London, UK.,Child Health Clinical Academic Group, King's College London, London, UK
| | - Stephen D Marks
- Paediatric Nephrology, Great Ormond Street Hospital For Children NHS Foundation Trust, London, UK.,Great Ormond Street Institute of Child Health, University College London, London, UK
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8
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Abstract
Industry-led culling of badgers has occurred in England to reduce the incidence of bovine tuberculosis in cattle for a number of years. Badger vaccination is also possible, and a move away from culling was "highly desirable" in a recent report to the UK government. Here we used an established simulation model to examine badger control option in a post-cull environment in England. These options included no control, various intermittent culling, badger vaccination and use of a vaccine combined with fertility control. The initial simulated cull led to a dramatic reduction in the number of infected badgers present, which increased slowly if there was no further badger management. All three approaches led to a further reduction in the number of infected badgers, with little to choose between the strategies. We do note that of the management strategies only vaccination on its own leads to a recovery of the badger population, but also an increase in the number of badgers that need to be vaccinated. We conclude that vaccination post-cull, appears to be particularly effective, compared to vaccination when the host population is at carrying capacity.
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Affiliation(s)
- Graham C. Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
- * E-mail:
| | - Richard Budgey
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
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9
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Reed BP, Cant DJH, Spencer SJ, Carmona-Carmona AJ, Bushell A, Herrera-Gómez A, Kurokawa A, Thissen A, Thomas AG, Britton AJ, Bernasik A, Fuchs A, Baddorf AP, Bock B, Theilacker B, Cheng B, Castner DG, Morgan DJ, Valley D, Willneff EA, Smith EF, Nolot E, Xie F, Zorn G, Smith GC, Yasufuku H, Fenton JL, Chen J, Counsell JDP, Radnik J, Gaskell KJ, Artyushkova K, Yang L, Zhang L, Eguchi M, Walker M, Hajdyła M, Marzec MM, Linford MR, Kubota N, Cortazar-Martínez O, Dietrich P, Satoh R, Schroeder SLM, Avval TG, Nagatomi T, Fernandez V, Lake W, Azuma Y, Yoshikawa Y, Shard AG. Versailles Project on Advanced Materials and Standards interlaboratory study on intensity calibration for x-ray photoelectron spectroscopy instruments using low-density polyethylene. J Vac Sci Technol A 2020; 38:063208. [PMID: 33281279 PMCID: PMC7688089 DOI: 10.1116/6.0000577] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/30/2020] [Indexed: 06/12/2023]
Abstract
We report the results of a Versailles Project on Advanced Materials and Standards interlaboratory study on the intensity scale calibration of x-ray photoelectron spectrometers using low-density polyethylene (LDPE) as an alternative material to gold, silver, and copper. An improved set of LDPE reference spectra, corrected for different instrument geometries using a quartz-monochromated Al Kα x-ray source, was developed using data provided by participants in this study. Using these new reference spectra, a transmission function was calculated for each dataset that participants provided. When compared to a similar calibration procedure using the NPL reference spectra for gold, the LDPE intensity calibration method achieves an absolute offset of ∼3.0% and a systematic deviation of ±6.5% on average across all participants. For spectra recorded at high pass energies (≥90 eV), values of absolute offset and systematic deviation are ∼5.8% and ±5.7%, respectively, whereas for spectra collected at lower pass energies (<90 eV), values of absolute offset and systematic deviation are ∼4.9% and ±8.8%, respectively; low pass energy spectra perform worse than the global average, in terms of systematic deviations, due to diminished count rates and signal-to-noise ratio. Differences in absolute offset are attributed to the surface roughness of the LDPE induced by sample preparation. We further assess the usability of LDPE as a secondary reference material and comment on its performance in the presence of issues such as variable dark noise, x-ray warm up times, inaccuracy at low count rates, and underlying spectrometer problems. In response to participant feedback and the results of the study, we provide an updated LDPE intensity calibration protocol to address the issues highlighted in the interlaboratory study. We also comment on the lack of implementation of a consistent and traceable intensity calibration method across the community of x-ray photoelectron spectroscopy (XPS) users and, therefore, propose a route to achieving this with the assistance of instrument manufacturers, metrology laboratories, and experts leading to an international standard for XPS intensity scale calibration.
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Affiliation(s)
- Benjamen P. Reed
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | - David J. H. Cant
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | - Steve J. Spencer
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | | | - Adam Bushell
- Thermo Fisher Scientific (Surface Analysis), East Grinstead RH19 1XZ, United Kingdom
| | | | - Akira Kurokawa
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Andreas Thissen
- SPECS Surface Nano Analysis GmbH, Voltastraße 5, 13355 Berlin, Germany
| | - Andrew G. Thomas
- School of Materials, Photon Science Institute and Sir Henry Royce Institute, Alan Turing Building, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Andrew J. Britton
- Versatile X-ray Spectroscopy Facility, School of Chemical and Process Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Andrzej Bernasik
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Anne Fuchs
- Robert Bosch GmbH, Robert-Bosch-Campus, 71272 Renningen, Germany
| | - Arthur P. Baddorf
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37830
| | - Bernd Bock
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | - Bill Theilacker
- Medtronic, 710 Medtronic Parkway, LT240, Fridley, Minnesota 55432
| | - Bin Cheng
- Analysis and Testing Center, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China
| | - David G. Castner
- National ESCA and Surface Analysis Center for Biomedical Problems, Department of Bioengineering and Chemical Engineering, University of Washington, Seattle, Washington 98195
| | - David J. Morgan
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, United Kingdom
| | - David Valley
- Physical Electronics Inc., East Chanhassen, Minnesota 55317
| | - Elizabeth A. Willneff
- Versatile X-ray Spectroscopy Facility, School of Design, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Emily F. Smith
- Nanoscale and Microscale Research Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | | | - Fangyan Xie
- Instrumental Analysis & Research Center, Sun Yat-sen University, Guangzhou 510275, People’s Republic of China
| | - Gilad Zorn
- GE Research, 1 Research Circle, K1 1D7A, Niskayuna, New York 12309
| | - Graham C. Smith
- Faculty of Science and Engineering, University of Chester, Thornton Science Park, Chester CH2 4NU, United Kingdom
| | - Hideyuki Yasufuku
- Materials Analysis Station, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0044, Japan
| | - Jeffery L. Fenton
- Medtronic, 6700 Shingle Creek Parkway, Brooklyn Center, Minnesota 55430
| | - Jian Chen
- Instrumental Analysis & Research Center, Sun Yat-sen University, Guangzhou 510275, People’s Republic of China
| | | | - Jörg Radnik
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 44-46, 12203 Berlin, Germany
| | - Karen J. Gaskell
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742
| | | | - Li Yang
- Department of Chemistry, Xi’an Jiaotong-Liverpool University, 111 Ren’ai Road, Suzhou Dushu Lake Science and Education Innovation District, Suzhou Industrial Park, Suzhou 215123, People’s Republic of China
| | - Lulu Zhang
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Makiho Eguchi
- Analysis Department, Materials Characterization Division, Futtsu Unit, Nippon Steel Technology Co. Ltd., 20-1 Shintomi, Futtsu City, Chiba 293-0011, Japan
| | - Marc Walker
- Department of Physics, University of Warwick, Coventry, West Midlands CV4 7AL, United Kingdom
| | - Mariusz Hajdyła
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Mateusz M. Marzec
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Matthew R. Linford
- Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo, Utah 84602
| | - Naoyoshi Kubota
- Analysis Department, Materials Characterization Division, Futtsu Unit, Nippon Steel Technology Co. Ltd., 20-1 Shintomi, Futtsu City, Chiba 293-0011, Japan
| | | | - Paul Dietrich
- SPECS Surface Nano Analysis GmbH, Voltastraße 5, 13355 Berlin, Germany
| | - Riki Satoh
- Analysis Department, Materials Characterization Division, Futtsu Unit, Nippon Steel Technology Co. Ltd., 20-1 Shintomi, Futtsu City, Chiba 293-0011, Japan
| | - Sven L. M. Schroeder
- Versatile X-ray Spectroscopy Facility, School of Chemical and Process Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Tahereh G. Avval
- Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo, Utah 84602
| | - Takaharu Nagatomi
- Platform Laboratory for Science and Technology, Asahi Kasei Corporation, 2-1 Samejima, Fuji, Shizuoka 416-8501, Japan
| | - Vincent Fernandez
- Université de Nantes, CNRS, Institut des Matériaux Jean Rouxel, IMN, F-44000 Nantes, France
| | - Wayne Lake
- Atomic Weapons Establishment (AWE), Aldermaston, Reading, Berkshire RG7 4PR, United Kingdom
| | - Yasushi Azuma
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Yusuke Yoshikawa
- Material Analysis Department, Yazaki Research and Technology Center, Yazaki Corporation, 1500 Mishuku, Susono-city, Shizuoka 410-1194, Japan
| | - Alexander G. Shard
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
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10
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Hulme PE, Baker R, Freckleton R, Hails RS, Hartley M, Harwood J, Marion G, Smith GC, Williamson M. The Epidemiological Framework for Biological Invasions (EFBI): an interdisciplinary foundation for the assessment of biosecurity threats. NB 2020. [DOI: 10.3897/neobiota.62.52463] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Emerging microparasite (e.g. viruses, bacteria, protozoa and fungi) epidemics and the introduction of non-native pests and weeds are major biosecurity threats worldwide. The likelihood of these threats is often estimated from probabilities of their entry, establishment, spread and ease of prevention. If ecosystems are considered equivalent to hosts, then compartment disease models should provide a useful framework for understanding the processes that underpin non-native species invasions. To enable greater cross-fertilisation between these two disciplines, the Epidemiological Framework for Biological Invasions (EFBI) is developed that classifies ecosystems in relation to their invasion status: Susceptible, Exposed, Infectious and Resistant. These states are linked by transitions relating to transmission, latency and recovery. This viewpoint differs markedly from the species-centric approaches often applied to non-native species. It allows generalisations from epidemiology, such as the force of infection, the basic reproductive ratio R0, super-spreaders, herd immunity, cordon sanitaire and ring vaccination, to be discussed in the novel context of non-native species and helps identify important gaps in the study of biological invasions. The EFBI approach highlights several limitations inherent in current approaches to the study of biological invasions including: (i) the variance in non-native abundance across ecosystems is rarely reported; (ii) field data rarely (if ever) distinguish source from sink ecosystems; (iii) estimates of the susceptibility of ecosystems to invasion seldom account for differences in exposure to non-native species; and (iv) assessments of ecosystem susceptibility often confuse the processes that underpin patterns of spread within -and between- ecosystems. Using the invasion of lakes as a model, the EFBI approach is shown to present a new biosecurity perspective that takes account of ecosystem status and complements demographic models to deliver clearer insights into the dynamics of biological invasions at the landscape scale. It will help to identify whether management of the susceptibility of ecosystems, of the number of vectors, or of the diversity of pathways (for movement between ecosystems) is the best way of limiting or reversing the population growth of a non-native species. The framework can be adapted to incorporate increasing levels of complexity and realism and to provide insights into how to monitor, map and manage biological invasions more effectively.
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11
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Chang X, Smith GC, Quinn J, Carson L, Chan CW, Lee S. Optimization of anti-wear and anti-bacterial properties of beta TiNb alloy via controlling duty cycle in open-air laser nitriding. J Mech Behav Biomed Mater 2020; 110:103913. [PMID: 32957212 DOI: 10.1016/j.jmbbm.2020.103913] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/27/2020] [Accepted: 06/04/2020] [Indexed: 11/17/2022]
Abstract
A multifunctional beta TiNb surface, featuring wear-resistant and antibacterial properties, was successfully created by means of open-air fibre laser nitriding. Beta TiNb alloy was selected in this study as it has low Young's modulus, is highly biocompatible, and thus can be a promising prosthetic joint material. It is, however, necessary to overcome intrinsically weak mechanical properties and poor wear resistance of beta TiNb in order to cover the range of applications to load-bearing and/or shearing parts. To this end, open-air laser nitriding technique was employed. A control of single processing parameter, namely duty cycle (between 5% and 100%), led to substantially different structural and functional properties of the processed beta TiNb surfaces as analyzed by an array of analytical tools. The TiNb samples nitrided at the DC condition of 60% showed a most enhanced performance in terms of improving surface hardness, anti-friction, anti-wear and anti-bacterial properties in comparison with other conditions. These findings are expected to be highly important and useful when TiNb alloys are considered as materials for hip/knee articular joint implants.
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Affiliation(s)
- Xianwen Chang
- Department of Mechanical Engineering, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Graham C Smith
- Faculty of Science and Engineering, University of Chester, Thornton Science Park, Chester, CH2 4NU, UK
| | - James Quinn
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Louise Carson
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Chi-Wai Chan
- School of Mechanical and Aerospace Engineering, Queen's University Belfast, BT9 5AH, UK.
| | - Seunghwan Lee
- Department of Mechanical Engineering, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark.
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12
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Smith F, Robertson A, Smith GC, Gill P, McDonald RA, Wilson G, Delahay RJ. Estimating wildlife vaccination coverage using genetic methods. Prev Vet Med 2020; 183:105096. [PMID: 32907707 DOI: 10.1016/j.prevetmed.2020.105096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 07/14/2020] [Indexed: 11/25/2022]
Abstract
Vaccination is a useful approach for the control of disease in wildlife populations. However, its effectiveness is dependent in part on delivery to a sufficient proportion of the target population. Measuring the proportions of wild animal populations that have been vaccinated is challenging and so there is a need to develop robust approaches that can contribute to our understanding of the likely efficacy of wildlife vaccination campaigns. We used a modified capture mark recapture technique to estimate vaccine coverage in a wild population of European badgers (Meles meles) vaccinated by live-trapping and injecting with Bacillus Calmette-Guérin as part of a bovine tuberculosis control initiative in Wales, United Kingdom. Our approach used genetic matching of vaccinated animals to a sample of the wider population to estimate the percentage of badgers that had been vaccinated. Individual-specific genetic profiles were obtained using microsatellite genotyping of hair samples, which were collected directly from trapped and vaccinated badgers and non-invasively from the wider population using hair traps deployed at badger burrows (setts). With two nights of trapping at each sett in an annual campaign, an estimated 50 % (95 % confidence interval 40-60 %) of the badger population received at least one dose of vaccine in a single year. Using a simple population model this suggested that the proportion of the population that would have received at least one dose of vaccine over the course of the four year vaccination campaign was between 67 % and 83 %. This is the first attempt, outside of field trials, to quantify the level of vaccine coverage achieved by trapping and injecting badgers, which is currently the only option for delivering BCG vaccine to this species. The results therefore have specific application to bTB control policy and the novel approach may have wider value in wildlife management and research.
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Affiliation(s)
- Freya Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK.
| | - Andrew Robertson
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK; Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9EZ, UK
| | - Graham C Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK
| | - Peter Gill
- Forensic Genetics Research Group, Oslo University Hospital and Also Department of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Robbie A McDonald
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9EZ, UK
| | - Gavin Wilson
- RSK Biocensus Limited, Suites 1-3 Bank House, Bond's Mill, Stonehouse, Gloucestershire, GL10 3RF, UK
| | - Richard J Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK
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13
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Affiliation(s)
- J C Kingdom
- Departments of Obstetrics & Gynaecology, The University of Toronto, Toronto, Canada
| | - G C Smith
- The University of Cambridge, Cambridge, UK
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14
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Croft S, Massei G, Smith GC, Fouracre D, Aegerter JN. Modelling Spatial and Temporal Patterns of African Swine Fever in an Isolated Wild Boar Population to Support Decision-Making. Front Vet Sci 2020; 7:154. [PMID: 32322589 PMCID: PMC7156605 DOI: 10.3389/fvets.2020.00154] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 03/03/2020] [Indexed: 11/13/2022] Open
Abstract
African swine fever (ASF) is a highly contagious disease affecting all suids including wild boar. As the disease can damage commercial pig production and its circulation can threaten international trade, understanding the risks produced by free-living wild boar (as a wildlife reservoir) is important to ensure proportionate policies to exclude the disease, as well as an effective contingency response. The recent spread of the virus into Western Europe has produced concerns in many stakeholders including pig producers and national governments. Unlike in mainland Europe, where wild boar are widespread, in Britain, free-living populations have only recently re-established, and whilst these are still relatively small and isolated, they may provide a sufficient reservoir capable of sustaining disease and may thus present a continual source of infection risk to domestic pigs. This study focuses on one component of the risk produced by wild boar, specifically the distribution and persistence of virus in a landscape produced by the natural circulation of disease within wild boar. We used a spatial individual-based model run across a representation of a real landscape to explore the epidemiological consequences of an introduction of ASF into the Forest of Dean, currently hosting the largest population of wild boar in England. We explore various scenarios including variations in the prophylactic management of boar, as well as variations in reactive management (contingency response) following the detection of disease to evaluate their value in reducing this specific risk (presence of ASF virus of wild boar origin in the landscape). The abundance and distribution of wild boar is predicted to increase across our study extent over the next 20 years. Outbreaks of ASF are not predicted to be self-sustaining, with the median time to disease "burn-out" (no new infections) being 14 weeks. Carcass removal, as a tool in a package of reactive management, was of limited value in reducing the duration of outbreaks in this study. We suggest that useful predictions of some of the risks produced by ASF might be possible using only the distribution of the boar, rather than more difficult abundance or density measures.
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Affiliation(s)
- Simon Croft
- National Wildlife Management Centre, Animal and Plant Health Agency, York, United Kingdom
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15
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Vicente J, Apollonio M, Blanco-Aguiar JA, Borowik T, Brivio F, Casaer J, Croft S, Ericsson G, Ferroglio E, Gavier-Widen D, Gortázar C, Jansen PA, Keuling O, Kowalczyk R, Petrovic K, Plhal R, Podgórski T, Sange M, Scandura M, Schmidt K, Smith GC, Soriguer R, Thulke HH, Zanet S, Acevedo P. Science-based wildlife disease response. Science 2019; 364:943-944. [PMID: 31171687 DOI: 10.1126/science.aax4310] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Joaquín Vicente
- National Institute on Wildlife Research (IREC), University of Castilla-La Mancha and Consejo Superior de Investigaciones Científicas, Ciudad Real, Spain. .,E.T.S. Ingenieros Agrónomos Ciudad Real, University of Castilla-La Mancha, Ciudad Real, Spain
| | - Marco Apollonio
- Department of Veterinary Medicine, University of Sassari, Sassari, Italy
| | - Jose A Blanco-Aguiar
- National Institute on Wildlife Research (IREC), University of Castilla-La Mancha and Consejo Superior de Investigaciones Científicas, Ciudad Real, Spain
| | - Tomasz Borowik
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland
| | - Francesca Brivio
- Department of Veterinary Medicine, University of Sassari, Sassari, Italy
| | - Jim Casaer
- Research Institute for Nature and Forest, Brussels, Belgium
| | - Simon Croft
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, UK
| | - Göran Ericsson
- Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Umea, Sweden
| | | | | | - Christian Gortázar
- National Institute on Wildlife Research (IREC), University of Castilla-La Mancha and Consejo Superior de Investigaciones Científicas, Ciudad Real, Spain
| | - Patrick A Jansen
- Wageningen University & Research, Wageningen, Netherlands.,Center for Tropical Forest Science, Smithsonian Tropical Research Institute, Balboa, Ancon, Panama
| | - Oliver Keuling
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Rafał Kowalczyk
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland
| | - Karolina Petrovic
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland
| | - Radim Plhal
- Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic
| | - Tomasz Podgórski
- Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland.,Czech University of Life Sciences, Prague, Czech Republic
| | - Marie Sange
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Massimo Scandura
- Department of Veterinary Medicine, University of Sassari, Sassari, Italy
| | - Krzysztof Schmidt
- Department of Veterinary Medicine, University of Sassari, Sassari, Italy
| | - Graham C Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, UK
| | - Ramon Soriguer
- E.T.S. Ingenieros Agrónomos Ciudad Real, University of Castilla-La Mancha, Ciudad Real, Spain
| | | | | | - Pelayo Acevedo
- National Institute on Wildlife Research (IREC), University of Castilla-La Mancha and Consejo Superior de Investigaciones Científicas, Ciudad Real, Spain.,E.T.S. Ingenieros Agrónomos Ciudad Real, University of Castilla-La Mancha, Ciudad Real, Spain
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16
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Ghonim S, Gatzoulis MA, Smith GC, Heng E, Ernst S, Li W, Keegan J, Diller GP, Dimpoulos K, Moon JC, Pennell DJ, Babu-Narayan SV. 2395LGE CMR predicts sudden death and VT in adults with repaired tetralogy of Fallot - a prospective study with 3500 patient follow up years. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Adults with repaired tetralogy of Fallot (rtoF) are at risk of ventricular arrhythmia and sudden cardiac death (SCD). Cross-sectional data suggest association of late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) with adverse clinical risk factors
Purpose
We sought to determine prognosis related to LGE CMR.
Methods
In this prospective cohort study the primary composite outcome comprised the first of cardiovascular death (SCD or heart failure-related), aborted SCD (successfully resuscitated cardiac arrest or appropriate AICD shock for ventricular fibrillation), and clinical sustained ventricular tachycardia (VT>30 seconds duration).
Results
In 531 rtoF patients (median age 32; 23–42, 296 (56%) male, NYHA≥II 17%) followed up after LGE CMR for median 5 (1.7–8.9) years, there were 39 primary composite outcomes: 10 SCD, 11 heart failure related deaths (2 perioperative RV failure), 2 aborted SCD and 16 clinical sustained VT events. At study end, there were 28 ventricular arrhythmic events in 28 rtoF patients (10 SCD, 16 clinical sustained VT, 2 aborted VF) that were significantly predicted by RV LGE extent (HR 1.45 CI: 1.3–1.6; P<0.001).
Univariable predictors of the primary outcome were RV LGE score; HR: 1.44 (1.31–1.57; p<0.001), (Figure) together with older age; HR: 1.05 (1.02–1.07; P<0.001), late repair; HR: 1.04 (1.02–1.07; p<0.001), lower RV ejection fraction; HR: 0.92 (0.89–0.95; p<0.001), larger RVOT akinetic length; HR: 1.04 (1.02–1.06; p<0.001) larger right atrial area; HR: 1.2 (1.12–1.29; p<0.001); higher BNP levels; HR: 1.01 (1–1.02; p<0.001), lower peak VO2; HR: 0.89 (0.83–0.96; p=0.001), prior atrial arrhythmia; HR: 5.3 (2.8–10.07; p<0.001), and non-sustained VT; HR: 4.1 (2.1–7.7; p<0.001). Inducible VT did not predict the primary outcome; HR: 2.1 (0.57–8; p=0.25)
In multivariable analysis both RV LGE score and indexed right atrial area (RAAi) only, remained predictive of the primary outcome (HR 1.29 CI: 1.12–1.49; p<0.001 and HR 1.1 CI: 1.02–1.12; p=0.01, respectively). Patients could accordingly be stratified such that supramedian RV LGE score (≥5) and RAAi ≥16cm2/m2 had 5-year event free survival 84% vs 94% for supramedian RV LGE score (≥5) and RAAi <16cm2/m2 or 98% for inframedian RV LGE score with RAAI<16cm2/m2. Figure.
Conclusions
For every unit increase in CMR defined RV fibrosis score there is a 44% increased risk of sudden cardiac death and VT. LGE CMR and maximal right atrial area should therefore be incorporated into risk stratification for sudden death in adults with rTOF.
Acknowledgement/Funding
British heart foundation
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Affiliation(s)
- S Ghonim
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - M A Gatzoulis
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - G C Smith
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - E Heng
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - S Ernst
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - W Li
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - J Keegan
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - G P Diller
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - K Dimpoulos
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - J C Moon
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - D J Pennell
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
| | - S V Babu-Narayan
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom
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Price RJ, Ladislaus PI, Smith GC, Davies TJ. A novel 'bottom-up' synthesis of few- and multi-layer graphene platelets with partial oxidation via cavitation. Ultrason Sonochem 2019; 56:466-473. [PMID: 31101286 DOI: 10.1016/j.ultsonch.2019.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 03/12/2019] [Accepted: 03/21/2019] [Indexed: 05/14/2023]
Abstract
The transient cavitation of diaromatic components such as 1-methylnaphthalene has been used to produce graphene platelets in a 'bottom-up' synthesis via the high temperature (>5000 K) conditions that are generated inside collapsing bubbles. Acoustic cavitation produced yields of 5.7 × 10-11 kgJ-1 at a production rate of 2.2 × 10-9 kgs-1. This can be improved by generating cavitation hydrodynamically, thus making commercial scale production viable. Hydrodynamic cavitation produced platelets with larger lateral dimensions (≥2 µm) than those formed by acoustic cavitation (10-200 nm). The partially oxidised nature of the platelets enables their covalent chemical functionalisation, which was achieved by combining suitable molecules in the reaction medium to affect a one-pot formation and functionalisation of graphene.
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Affiliation(s)
- Richard J Price
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester, Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, UK.
| | - Paul I Ladislaus
- Thomas Swan Ltd., Rotary Way, Consett, County Durham DH8 7ND, UK
| | - Graham C Smith
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester, Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, UK
| | - Trevor J Davies
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester, Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, UK
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18
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Croft S, Ward AI, Aegerter JN, Smith GC. Modeling current and potential distributions of mammal species using presence-only data: A case study on British deer. Ecol Evol 2019; 9:8724-8735. [PMID: 31410275 PMCID: PMC6686353 DOI: 10.1002/ece3.5424] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/04/2019] [Accepted: 06/14/2019] [Indexed: 11/07/2022] Open
Abstract
AIM Decisions on wildlife conservation, management, and epidemiological risk are best based on robust evidence. The continual improvement of species distributions, such that they can be relied upon in decision-making, is important. Here we seek to refine aspects of a generic modelling approach and improve the utility of species distribution maps. LOCATION Great Britain (GB). METHODS We applied a modeling framework based on hierarchical Bayesian species distribution models exploiting opportunistic occurrence records from citizen science datasets to predict both current and potential distributions for each of the six deer species known to be present in GB. Using the resulting maps, we performed a simple analysis of the overlap between species to illustrate possible contact, which we interpret as the relative risk of potential disease spread given an introduction. RESULTS Predicted distribution maps showed good agreement with the broader scale occurrence reported by a recent national deer survey with an average True Skill Statistics and AUC of 0.69 and 0.89, respectively. Aggregation of the maps for all species highlighted regions of central and eastern England as well as parts of Scotland where extensive areas of range overlap could result in interspecific contact with consequences for risk assessments for diseases of deer. However, if populations are allowed to expand to their predicted potential, then areas of overlap, and therefore disease interspecific transmission risk, will become extensive and widespread across all of mainland Britain. MAIN CONCLUSIONS The generic modeling approach outlined performed well across all of the deer species tested, offering a robust and reliable tool through which current and potential animal distributions can be estimated and presented. Our application, intended to inform quantitative risk assessments, demonstrates the practical use of such outputs to generate the valuable evidence required to inform policy decisions on issues such as management strategy.
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Affiliation(s)
- Simon Croft
- National Wildlife Management CentreAnimal and Plant Health AgencyYorkUK
| | - Alastair I. Ward
- National Wildlife Management CentreAnimal and Plant Health AgencyYorkUK
- Department of Biological and Marine SciencesUniversity of HullHullUK
| | - James N. Aegerter
- National Wildlife Management CentreAnimal and Plant Health AgencyYorkUK
| | - Graham C. Smith
- National Wildlife Management CentreAnimal and Plant Health AgencyYorkUK
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19
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Halevas E, Mavroidi B, Swanson CH, Smith GC, Moschona A, Hadjispyrou S, Salifoglou A, Pantazaki AA, Pelecanou M, Litsardakis G. Magnetic cationic liposomal nanocarriers for the efficient drug delivery of a curcumin-based vanadium complex with anticancer potential. J Inorg Biochem 2019; 199:110778. [PMID: 31442839 DOI: 10.1016/j.jinorgbio.2019.110778] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/12/2019] [Accepted: 07/14/2019] [Indexed: 01/10/2023]
Abstract
In this work novel magnetic cationic liposomal nanoformulations were synthesized for the encapsulation of a crystallographically defined ternary V(IV)-curcumin-bipyridine (VCur) complex with proven bioactivity, as potential anticancer agents. The liposomal vesicles were produced via the thin film hydration method employing N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium (DOTAP) and egg phosphatidylcholine lipids and were magnetized through the addition of citric acid surface-modified monodispersed magnetite colloidal magnetic nanoparticles. The obtained nanoformulations were evaluated for their structural and textural properties and shown to have exceptional stability and enhanced solubility in physiological media, demonstrated by the entrapment efficiency and loading capacity results and the in vitro release studies of their cargo. Furthermore, the generated liposomal formulations preserved the superparamagnetic behavior of the employed magnetic core maintaining the physicochemical and morphological requirements for targeted drug delivery applications. The novel nanomaterials were further biologically evaluated for their DNA interaction potential and were found to act as intercalators. The findings suggest that the positively charged magnetic liposomal nanoformulations can generate increased concentration of their cargo at the DNA site, offering a further dimension in the importance of cationic liposomes as nanocarriers of hydrophobic anticancer metal ion complexes for the development of new multifunctional pharmaceutical nanomaterials with enhanced bioavailability and targeted antitumor activity.
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Affiliation(s)
- Eleftherios Halevas
- Laboratory of Materials for Electrotechnics, Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; Institute of Biosciences & Applications, National Centre for Scientific Research "Demokritos", 15310 Athens, Greece.
| | - Barbara Mavroidi
- Institute of Biosciences & Applications, National Centre for Scientific Research "Demokritos", 15310 Athens, Greece
| | - Claudia H Swanson
- Department of Natural Sciences, University of Chester, Thornton Science Park, Chester CH2 4NU, UK
| | - Graham C Smith
- Department of Natural Sciences, University of Chester, Thornton Science Park, Chester CH2 4NU, UK
| | - Alexandra Moschona
- Laboratory of Organic Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Spyros Hadjispyrou
- Laboratory of Inorganic Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Athanasios Salifoglou
- Laboratory of Inorganic Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Anastasia A Pantazaki
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Maria Pelecanou
- Institute of Biosciences & Applications, National Centre for Scientific Research "Demokritos", 15310 Athens, Greece
| | - George Litsardakis
- Laboratory of Materials for Electrotechnics, Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
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Croft S, Aegerter JN, Massei G, Smith GC. The risk of foot-and-mouth disease becoming endemic in a wildlife host is driven by spatial extent rather than density. PLoS One 2019; 14:e0218898. [PMID: 31242228 PMCID: PMC6594678 DOI: 10.1371/journal.pone.0218898] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 06/11/2019] [Indexed: 11/18/2022] Open
Abstract
In the past 20 years, free living populations of feral wild boar have re-established in several locations across the UK. One of the largest populations is in the Forest of Dean where numbers have been steadily increasing since monitoring began in 2008, with estimates from 2016 reporting a population of more than 1500. Feral wild boar have significant ecological and environmental impacts and may present a serious epidemiological risk to neighbouring livestock as they are a vector for a number of important livestock diseases. This includes foot-and-mouth disease (FMD) which is currently absent from the UK. We developed an individual-based spatially explicit modelling approach to simulate feral wild boar populations in the Forest of Dean (England, UK) and use it to explore whether current or future populations might be sufficient to produce long-lived outbreaks of FMD in this potential wildlife reservoir. Our findings suggest that if you exclude the spread from feral wild boar to other susceptible species, the current population of boar is insufficient to maintain FMD, with 95% of unmanaged simulations indicating disease burn-out within a year (not involving boar management specifically for disease). However, if boar are allowed to spread beyond their current range into the adjacent landscape, they might maintain a self-sustaining reservoir of infection for the disease.
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Affiliation(s)
- Simon Croft
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - James N. Aegerter
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Giovanna Massei
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Graham C. Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
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21
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Ghonim S, Gatehouse PD, Giblin G, Keegan J, Smith GC, Mathews GC, Jenkins S, Alpendurada F, Dimopoulos K, Pennell DJ, Li W, Moon JC, Gatzoulis M, Babu-Narayan S. 277Can RV optimised native T1 mapping and ECV add clinical value in repaired tetralogy of Fallot? Eur Heart J Cardiovasc Imaging 2019. [DOI: 10.1093/ehjci/jez121.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- S Ghonim
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - P D Gatehouse
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - G Giblin
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - J Keegan
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - G C Smith
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - G C Mathews
- Royal Brompton Hospital, London, United Kingdom of Great Britain & Northern Ireland
| | - S Jenkins
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - F Alpendurada
- Royal Brompton Hospital, London, United Kingdom of Great Britain & Northern Ireland
| | - K Dimopoulos
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - D J Pennell
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - W Li
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - J C Moon
- Barts Health NHS Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - M Gatzoulis
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
| | - S Babu-Narayan
- Royal Brompton Hospital, Imperial College London, National Heart Lung Institute, London, United Kingdom of Great Britain & Northern Ireland
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22
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Kumar D, Stoichkov V, Brousseau E, Smith GC, Kettle J. Correction: High performing AgNW transparent conducting electrodes with a sheet resistance of 2.5 Ω Sq -1 based upon a roll-to-roll compatible post-processing technique. Nanoscale 2019; 11:5771. [PMID: 30855062 DOI: 10.1039/c9nr90049g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Correction for 'High performing AgNW transparent conducting electrodes with a sheet resistance of 2.5 Ω Sq-1 based upon a roll-to-roll compatible post-processing technique' by D. Kumar et al., Nanoscale, 2019, DOI: 10.1039/c8nr07974a.
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Affiliation(s)
- D Kumar
- School of Electronics, Bangor University, Dean St, Bangor, Gwynedd, LL57 1UT, Wales, UK.
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23
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Kumar D, Stoichkov V, Brousseau E, Smith GC, Kettle J. High performing AgNW transparent conducting electrodes with a sheet resistance of 2.5 Ω Sq -1 based upon a roll-to-roll compatible post-processing technique. Nanoscale 2019; 11:5760-5769. [PMID: 30775736 DOI: 10.1039/c8nr07974a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A report of transparent and conducting silver nanowires (AgNWs) that produce remarkable electrical performance, surface planarity and environmental stability is given. This research presents an innovative process that relies on three sequential steps, which are roll-to-roll (R2R) compatible: thermal embossing, infrared sintering and plasma treatment. This process leads to the demonstration of a conductive film with a sheet resistance of 2.5 Ω sq-1 and high transmittance, thus demonstrating the highest reported figure-of-merit in AgNWs to date (FoM = 933). A further benefit of the process is that the surface roughness is substantially reduced compared to traditional AgNW processing techniques. The consideration of the long-term stability is given by developing an accelerated life test process that simultaneously stresses the applied bias and temperature. Regression line fitting shows that a ∼150-times improvement in stability is achieved under 'normal operational conditions' when compared to traditionally deposited AgNW films. X-ray photoelectron spectroscopy (XPS) is used to understand the root cause of the improvement in long-term stability, which is related to reduced chemical changes in the AgNWs.
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Affiliation(s)
- D Kumar
- School of Electronics, Bangor University, Dean St, Bangor, Gwynedd LL57 1UT, Wales, UK.
| | - V Stoichkov
- School of Electronics, Bangor University, Dean St, Bangor, Gwynedd LL57 1UT, Wales, UK.
| | - E Brousseau
- Department of Natural Sciences, University of Chester, Thornton Science Park, Chester CH2 4NU, UK
| | - G C Smith
- Institute of Mechanical and Manufacturing Engineering, Cardiff School of Engineering, Cardiff University, Queen's buildings, The Parade, Cardiff CF24 3AA, UK
| | - J Kettle
- School of Electronics, Bangor University, Dean St, Bangor, Gwynedd LL57 1UT, Wales, UK.
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24
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Smith GC. The role of modelling in predicting rabies and understanding the impact of control measures. REV SCI TECH OIE 2019; 37:551-557. [PMID: 30747126 DOI: 10.20506/rst.37.2.2823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Rabies is probably the most commonly modelled disease as both its epidemiology and host dynamics are well understood. Models are simplifications of reality and there are different approaches to achieving these representations. Over time, modelling has moved from simple mathematical methods towards more realistic biological models that incorporate spatial and individual variation. In this article, the author reviews models that have increased our understanding of actions taken to manage disease. The most developed of these focus on fox (Vulpes vulpes) rabies in Europe, where a suite of models has helped researchers to explore fox management options and the complications caused by other potential hosts, such as raccoon dogs (Nyctereutes procyonoides). Models of dog (Canis familiaris) rabies support the idea of a 70% vaccine threshold for disease elimination and are now being used to explore and optimise management methods, combining vaccination with either surgical sterilisation or the use of chemical sterilisation. Future challenges are also identified, such as the need to develop practical management models in other hosts, and to explore different Lyssavirus strains in bats.
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25
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Randviir EP, Kanou O, Liauw CM, Miller GJ, Andrews HG, Smith GC. The physicochemical investigation of hydrothermally reduced textile waste and application within carbon-based electrodes. RSC Adv 2019; 9:11239-11252. [PMID: 35520266 PMCID: PMC9063389 DOI: 10.1039/c9ra00175a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/25/2019] [Indexed: 01/12/2023] Open
Abstract
Textile waste is on the rise due to the expanding global population and the fast fashion market. Large volumes of textile waste are increasing the need for new methods for recycling mixed fabric materials. This paper employs a hydrothermal conversion route for a polyester/cotton mix in phosphoric acid to generate carbon materials (hydrochars) for electrochemical applications. A combination of characterization techniques revealed the reaction products were largely comprised of two major components. The first is a granular material with a surface C : O ratio of 2 : 1 interspersed with phosphorous and titanium proved using energy dispersive X-ray spectroscopy, and the other is a crystalline material with a surface C : O ratio of 3 : 2 containing no phosphorous or titanium. The latter material was found via X-ray diffraction and differential scanning calorimetry to be terephthalic acid. Electrochemical experiments conducted using the hydrochar as a carbon paste electrode demonstrates an increase in current response compared to carbon reference materials. The improved current responses, intrinsically related to the surface area of the material, could be beneficial for electrochemical sensor applications, meaning that this route holds promise for the development of a cheap recycled carbon material, using straightforward methods and simple laboratory reagents. A novel method for chemically processing blended textiles is investigated, revealing a conductive carbon material as a major product.![]()
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Affiliation(s)
- Edward P. Randviir
- School of Science and the Environment
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Omar Kanou
- School of Science and the Environment
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Christopher M. Liauw
- School of Healthcare Science
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Gary J. Miller
- Technical Services
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Hayley G. Andrews
- Technical Services
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Graham C. Smith
- Department of Natural Sciences
- Faculty of Science & Engineering
- University of Chester
- Chester CH2 4NU
- UK
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26
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Abstract
Computer modeling has a long history of association with epidemiology, and has improved our understanding of the theory of disease dynamics and provided insights into wildlife disease management. A summary of badger bovine TB models and their role in decision making is presented, from a simple initial SEI model, to SEIR (inclusion of a recovered category) and SEI1I2 (inclusion of two stages of disease progression) variants, and subsequent spatially-explicit individual-based models used to assess historical badger management strategies. The integration of cattle into TB models allowed comparison of the predicted impacts of different badger management strategies on cattle herd breakdown rates, and provided an economic dimension to the outputs. Estimates of R0 for bovine TB in cattle and badgers are little higher than unity implying that the disease should be relatively easy to control, which is at odds with practical experience. A cohort of recent models have suggested that combined strategies, involving management of both host species and including vaccination may be most effective. Future models of badger vaccination will need to accommodate the partial protection from infection and likely duration of immunity conferred by the currently available vaccine (BCG). Descriptions of how models could better represent the ecological and epidemiological complexities of the badger-cattle TB system are presented, along with a wider discussion of the utility of modeling for bovine TB management interventions. This includes consideration of the information required to maximize the utility of the next generation of models.
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Affiliation(s)
- Graham C Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, York, United Kingdom
| | - Richard J Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, York, United Kingdom
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27
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Halevas E, Papadopoulos TA, Swanson CH, Smith GC, Hatzidimitriou A, Katsipis G, Pantazaki A, Sanakis I, Mitrikas G, Ypsilantis K, Litsardakis G, Salifoglou A. In-depth synthetic, physicochemical and in vitro biological investigation of a new ternary V(IV) antioxidant material based on curcumin. J Inorg Biochem 2018; 191:94-111. [PMID: 30476714 DOI: 10.1016/j.jinorgbio.2018.10.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 10/21/2018] [Accepted: 10/23/2018] [Indexed: 01/28/2023]
Abstract
Curcumin is a natural product with a broad spectrum of beneficial properties relating to pharmaceutical applications, extending from traditional remedies to modern cosmetics. The biological activity of such pigments, however, is limited by their solubility and bioavailability, thereby necessitating new ways of achieving optimal tissue cellular response and efficacy as drugs. Metal ion complexation provides a significant route toward improvement of curcumin stability and biological activity, with vanadium being a representative such metal ion, amply encountered in biological systems and exhibiting exogenous bioactivity through potential pharmaceuticals. Driven by the need to optimally increase curcumin bioavailability and bioactivity through complexation, synthetic efforts were launched to seek out stable species, ultimately leading to the synthesis and isolation of a new ternary V(IV)-curcumin-(2,2'-bipyridine) complex. Physicochemical characterization (elemental analysis, FT-IR, Thermogravimetry (TGA), UV-Visible, NMR, ESI-MS, Fluorescence, X-rays) portrayed the solid-state and solution properties of the ternary complex. Pulsed-EPR spectroscopy, in frozen solutions, suggested the presence of two species, cis- and trans-conformers. Density Functional Theory (DFT) calculations revealed the salient features and energetics of the two conformers, thereby complementing EPR spectroscopy. The well-described profile of the vanadium species led to its in vitro biological investigation involving toxicity, cell metabolism inhibition in S. cerevisiae cultures, Reactive Oxygen Species (ROS)-suppressing capacity, lipid peroxidation, and plasmid DNA degradation. A multitude of bio-assays and methodologies, in comparison to free curcumin, showed that it exhibits its antioxidant potential in a concentration-dependent fashion, thereby formulating a bioreactivity profile supporting development of new efficient vanado-pharmaceuticals, targeting (extra)intra-cellular processes under (patho)physiological conditions.
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Affiliation(s)
- E Halevas
- Laboratory of Inorganic Chemistry and Advanced Materials, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; Laboratory of Materials for Electrotechnics, Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - T A Papadopoulos
- Department of Natural Sciences, Thornton Science Park, University of Chester, Chester, CH3 4NU, UK
| | - C H Swanson
- Department of Natural Sciences, Thornton Science Park, University of Chester, Chester, CH3 4NU, UK
| | - G C Smith
- Department of Natural Sciences, Thornton Science Park, University of Chester, Chester, CH3 4NU, UK
| | - A Hatzidimitriou
- Laboratory of Inorganic Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - G Katsipis
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - A Pantazaki
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - I Sanakis
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Aghia Paraskevi 15310, Attiki, Greece
| | - G Mitrikas
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Aghia Paraskevi 15310, Attiki, Greece
| | - K Ypsilantis
- Department of Chemistry, University of Ioannina, Ioannina 45110, Greece
| | - G Litsardakis
- Laboratory of Materials for Electrotechnics, Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - A Salifoglou
- Laboratory of Inorganic Chemistry and Advanced Materials, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
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28
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Croft S, Brown M, Wilkins S, Hart A, Smith GC. Evaluating European Food Safety Authority Protection Goals for Honeybees (Apis mellifera): What Do They Mean for Pollination? Integr Environ Assess Manag 2018; 14:750-758. [PMID: 29923683 DOI: 10.1002/ieam.4078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 02/04/2018] [Accepted: 06/12/2018] [Indexed: 06/08/2023]
Abstract
In recent years there has been growing concern regarding the sudden and unexplained failure of honeybee (Apis mellifera) colonies. Several factors have been suggested, including pesticides. In an effort to regulate their impact, guidance published by the European Food Safety Authority (EFSA) has recommended that the magnitude of effects on exposed colonies should not exceed 7% reduction in colony size after 2 brood cycles. However, fears have been raised regarding the practicality of measuring such a loss in the field. It is also unclear how this protection goal relates to maintaining the ecosystem services provided by bees, which we argue should be a primary objective for regulators. Here, we evaluate what these protection goals mean in relation to ecosystems performance using a computational colony model that incorporates mechanisms to simulate both lethal and sublethal pesticide effects. To these simulations, we apply a testing regime similar to that commonly used in field trials to produce standard assessment metrics. By relating these measures to losses in forager activity, we aim to identify which could be used as effective indicators of reduced ecoservice and to quantify acceptable limits below which performance can be maintained. Our findings show that loss of colony size is the best indicator of reduced ecoservice. Metrics that focus on specific colony functions such as increased brood or forager mortality are ineffective indicators for all types of simulated pesticide effects. At the levels of colony loss recommended by EFSA, using our default parameterization, we predict a loss of ecosystems performance of 3% to 4%. However, based on an extensive sensitivity analysis, it is clear that this estimate is subject to substantial uncertainty with losses under alternative parameterizations of up to 14%. Nevertheless, our model provides a valuable framework for assessing protection goals, allowing regulators to test relevant impacts and quantify their magnitude. Integr Environ Assess Manag 2018;14:750-758. © 2018 Crown Copyright and SETAC.
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Affiliation(s)
- Simon Croft
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Mike Brown
- National Bee Unit, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Selwyn Wilkins
- Fera Science, National Agri-Food Innovation Campus, Sand Hutton, York, United Kingdom
| | - Andy Hart
- Fera Science, National Agri-Food Innovation Campus, Sand Hutton, York, United Kingdom
| | - Graham C Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
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29
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Slate AJ, Brownson DAC, Abo Dena AS, Smith GC, Whitehead KA, Banks CE. Exploring the electrochemical performance of graphite and graphene paste electrodes composed of varying lateral flake sizes. Phys Chem Chem Phys 2018; 20:20010-20022. [PMID: 30022207 DOI: 10.1039/c8cp02196a] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the fabrication, characterisation (SEM/EDX, TEM, XRD, XPS and Raman spectroscopy) and electrochemical properties of graphite and graphene paste electrodes with varying lateral flake sizes. The fabricated paste electrodes are electrochemically analysed using both outer-sphere and inner-sphere redox probes, namely; hexaammineruthenium(iii) chloride, N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), potassium ferrocyanide(ii) and ammonium ferrous(ii) sulphate. Upon comparison of different graphite paste electrodes, a clear correlation between the lateral flake sizes (La), ranging from 1.5 mm-0.5 μm, and electrochemical activity (heterogeneous electron transfer (HET) kinetics) is evident, where an improvement in the HET is observed at smaller lateral flake sizes. We infer that the beneficial response evident when employing laterally smaller flakes is due to an increased number of edge plane like-sites/defects available upon the electrode surface, facilitating electron transfer. Interestingly, given that the overall lateral flake sizes of the graphenes utilised (10.0-1.3 μm) were significantly smaller than those studied previously, an improvement in HET kinetics was also evident with the reduction of lateral flake size; the extent to which is redox-probe dependent. Improvements are observed up to a distinct point, termed the 'lateral size threshold' (ca. ≤2 μm) where the electrochemical reversible limit is approached. Further support is provided from density functional theory (DFT), exploring the electronic structure (i.e. HOMO-LUMO) as a function of flake size, which demonstrates that the coverage of edge plane like-sites/defects comprising the geometric structure of the relatively small graphene flakes is such that effectively the entire flake has become electrochemically active. In this study, the importance of lateral flake size with respect to electrochemical reactivity at carbon-based electrodes has been demonstrated alongside a structural relationship upon HET performance, a phenomenon that has not previously been described in the literature. Such work is both highly important and informative for the field of electrochemistry and electrode performance, with potential implications in a plethora of areas, ranging from novel renewable energy sources to electroanalytical sensing platforms.
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Affiliation(s)
- Anthony J Slate
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester, M1 5GD, UK.
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30
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Rowley-Neale S, Ratova M, Fugita LTN, Smith GC, Gaffar A, Kulczyk-Malecka J, Kelly PJ, Banks CE. Magnetron Sputter-Coated Nanoparticle MoS 2 Supported on Nanocarbon: A Highly Efficient Electrocatalyst toward the Hydrogen Evolution Reaction. ACS Omega 2018; 3:7235-7242. [PMID: 31458885 PMCID: PMC6644582 DOI: 10.1021/acsomega.8b00258] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 06/07/2018] [Indexed: 05/11/2023]
Abstract
The design and fabrication of inexpensive highly efficient electrocatalysts for the production of hydrogen via the hydrogen evolution reaction (HER) underpin a plethora of emerging clean energy technologies. Herein, we report the fabrication of highly efficient electrocatalysts for the HER based on magnetron-sputtered MoS2 onto a nanocarbon support, termed MoS2/C. Magnetron sputtering time is explored as a function of its physiochemical composition and HER performance; increased sputtering times give rise to materials with differing compositions, i.e., Mo4+ to Mo6+ and associated S anions (sulfide, elemental, and sulfate), and improved HER outputs. An optimized sputtering time of 45 min was used to fabricate the MoS2/C material. This gave rise to an optimal HER performance with regard to its HER onset potential, achievable current, and Tafel value, which were -0.44 (vs saturated calomel electrode (SCE)), -1.45 mV s-1, and 43 mV dec-1, respectively, which has the highest composition of Mo4+ and sulfide (MoS2). Electrochemical testing toward the HER via drop casting MoS2/C upon screen-printed electrodes (SPEs) to electrically wire the nanomaterial is found to be mass coverage dependent, where the current density increases up to a critical mass (ca. 50 μg cm-2), after which a plateau is observed. To allow for a translation of the bespoke fabricated MoS2/C from laboratory to new industrial applications, MoS2/C was incorporated into the bulk ink utilized in the fabrication of SPEs (denoted as MoS2/C-SPE), thus allowing for improved electrical wiring to the MoS2/C and resulting in the production of scalable and reproducible electrocatalytic platforms. The MoS2/C-SPEs displayed far greater HER catalysis with a 450 mV reduction in the HER onset potential and a 1.70 mA cm-2 increase in the achievable current density (recorded at -0.75 V (vs SCE)), compared to a bare/unmodified graphitic SPE. The approach of using magnetron sputtering to modify carbon with MoS2 facilitates the production of mass-producible, stable, and effective electrode materials for possible use in electrolyzers, which are cost competitive to Pt and mitigate the need to use time-consuming and low-yield exfoliation techniques typically used to fabricate pristine MoS2.
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Affiliation(s)
- Samuel
J. Rowley-Neale
- Faculty
of Science and Engineering and Manchester Fuel Cell Innovation
Centre, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, U.K.
| | - Marina Ratova
- Faculty
of Science and Engineering and Manchester Fuel Cell Innovation
Centre, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, U.K.
| | - Lucas T. N. Fugita
- University
of São Paulo, 580, Prof. Lineu Prestes Avenue, Butantã, São Paulo 05508-000, SP, Brazil
| | - Graham C. Smith
- Department
of Natural Sciences, Faculty of Science and Engineering, University of Chester, Thornton Science Park, Pool Lane,
Ince, Chester CH2 4NU, U.K.
| | - Amer Gaffar
- Faculty
of Science and Engineering and Manchester Fuel Cell Innovation
Centre, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, U.K.
| | - Justyna Kulczyk-Malecka
- Faculty
of Science and Engineering and Manchester Fuel Cell Innovation
Centre, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, U.K.
| | - Peter J. Kelly
- Faculty
of Science and Engineering and Manchester Fuel Cell Innovation
Centre, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, U.K.
| | - Craig E. Banks
- Faculty
of Science and Engineering and Manchester Fuel Cell Innovation
Centre, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, U.K.
- E-mail: . Tel: ++(0)1612471196. Fax: ++(0)1612476831. Website: www.craigbanksresearch.com
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31
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Scott DM, Baker R, Charman N, Karlsson H, Yarnell RW, Mill AC, Smith GC, Tolhurst BA. A citizen science based survey method for estimating the density of urban carnivores. PLoS One 2018; 13:e0197445. [PMID: 29787598 PMCID: PMC5963764 DOI: 10.1371/journal.pone.0197445] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 05/02/2018] [Indexed: 11/19/2022] Open
Abstract
Globally there are many examples of synanthropic carnivores exploiting growth in urbanisation. As carnivores can come into conflict with humans and are potential vectors of zoonotic disease, assessing densities in suburban areas and identifying factors that influence them are necessary to aid management and mitigation. However, fragmented, privately owned land restricts the use of conventional carnivore surveying techniques in these areas, requiring development of novel methods. We present a method that combines questionnaire distribution to residents with field surveys and GIS, to determine relative density of two urban carnivores in England, Great Britain. We determined the density of: red fox (Vulpes vulpes) social groups in 14, approximately 1km2 suburban areas in 8 different towns and cities; and Eurasian badger (Meles meles) social groups in three suburban areas of one city. Average relative fox group density (FGD) was 3.72 km-2, which was double the estimates for cities with resident foxes in the 1980’s. Density was comparable to an alternative estimate derived from trapping and GPS-tracking, indicating the validity of the method. However, FGD did not correlate with a national dataset based on fox sightings, indicating unreliability of the national data to determine actual densities or to extrapolate a national population estimate. Using species-specific clustering units that reflect social organisation, the method was additionally applied to suburban badgers to derive relative badger group density (BGD) for one city (Brighton, 2.41 km-2). We demonstrate that citizen science approaches can effectively obtain data to assess suburban carnivore density, however publicly derived national data sets need to be locally validated before extrapolations can be undertaken. The method we present for assessing densities of foxes and badgers in British towns and cities is also adaptable to other urban carnivores elsewhere. However this transferability is contingent on species traits meeting particular criteria, and on resident responsiveness.
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Affiliation(s)
- Dawn M. Scott
- Conservation Ecology and Zoonosis Research Group, University of Brighton, Brighton, United Kingdom
- * E-mail:
| | - Rowenna Baker
- Conservation Ecology and Zoonosis Research Group, University of Brighton, Brighton, United Kingdom
| | - Naomi Charman
- Conservation Ecology and Zoonosis Research Group, University of Brighton, Brighton, United Kingdom
| | - Heidi Karlsson
- Conservation Ecology and Zoonosis Research Group, University of Brighton, Brighton, United Kingdom
| | - Richard W. Yarnell
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Brackenhurst Campus, Southwell, United Kingdom
| | - Aileen C. Mill
- Centre for Wildlife Management, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Graham C. Smith
- Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Bryony A. Tolhurst
- Conservation Ecology and Zoonosis Research Group, University of Brighton, Brighton, United Kingdom
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Brownson DAC, Smith GC, Banks CE. Graphene oxide electrochemistry: the electrochemistry of graphene oxide modified electrodes reveals coverage dependent beneficial electrocatalysis. R Soc Open Sci 2017; 4:171128. [PMID: 29291099 PMCID: PMC5717673 DOI: 10.1098/rsos.171128] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 10/04/2017] [Indexed: 05/21/2023]
Abstract
The modification of electrode surfaces is widely implemented in order to try and improve electron transfer kinetics and surface interactions, most recently using graphene related materials. Currently, the use of 'as is' graphene oxide (GO) has been largely overlooked, with the vast majority of researchers choosing to reduce GO to graphene or use it as part of a composite electrode. In this paper, 'as is' GO is explored and electrochemically characterized using a range of electrochemical redox probes, namely potassium ferrocyanide(II), N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), dopamine hydrochloride and epinephrine. Furthermore, the electroanalytical efficacy of GO is explored towards the sensing of dopamine hydrochloride and epinephrine via cyclic voltammetry. The electrochemical response of GO is benchmarked against pristine graphene and edge plane-/basal plane pyrolytic graphite (EPPG and BPPG respectively) alternatives, where the GO shows an enhanced electrochemical/electroanalytical response. When using GO as an electrode material, the electrochemical response of the analytes studied herein deviate from that expected and exhibit altered electrochemical responses. The oxygenated species encompassing GO strongly influence and dominate the observed voltammetry, which is crucially coverage dependent. GO electrocatalysis is observed, which is attributed to the presence of beneficial oxygenated species dictating the response in specific cases, demonstrating potential for advantageous electroanalysis to be realized. Note however, that crucial coverage based regions are observed at GO modified electrodes, owing to the synergy of edge plane sites and oxygenated species. We report the true beneficial electrochemistry of GO, which has enormous potential to be beneficially used in various electrochemical applications 'as is' rather than be simply used as a precursor to making graphene and is truly a fascinating member of the graphene family.
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Affiliation(s)
- Dale A. C. Brownson
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK
| | - Graham C. Smith
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester, Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, UK
| | - Craig E. Banks
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK
- Author for correspondence: Craig E. Banks e-mail:
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Rowley-Neale SJ, Smith GC, Banks CE. Mass-Producible 2D-MoS 2-Impregnated Screen-Printed Electrodes That Demonstrate Efficient Electrocatalysis toward the Oxygen Reduction Reaction. ACS Appl Mater Interfaces 2017; 9:22539-22548. [PMID: 28573849 DOI: 10.1021/acsami.7b05104] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Two-dimensional molybdenum disulfide (2D-MoS2) screen-printed electrodes (2D-MoS2-SPEs) have been designed, fabricated, and evaluated toward the electrochemical oxygen reduction reaction (ORR) within acidic aqueous media. A screen-printable ink has been developed that allows for the tailoring of the 2D-MoS2 content/mass used in the fabrication of the 2D-MoS2-SPEs, which critically affects the observed ORR performance. In comparison to the graphite SPEs (G-SPEs), the 2D-MoS2-SPEs are shown to exhibit an electrocatalytic behavior toward the ORR which is found, critically, to be reliant upon the percentage mass incorporation of 2D-MoS2 in the 2D-MoS2-SPEs; a greater percentage mass of 2D-MoS2 incorporated into the 2D-MoS2-SPEs results in a significantly less electronegative ORR onset potential and a greater signal output (current density). Using optimally fabricated 2D-MoS2-SPEs, an ORR onset and a peak current of approximately +0.16 V [vs saturated calomel electrode (SCE)] and -1.62 mA cm-2, respectively, are observed, which exceeds the -0.53 V (vs SCE) and -635 μA cm-2 performance of unmodified G-SPEs, indicating an electrocatalytic response toward the ORR utilizing the 2D-MoS2-SPEs. An investigation of the underlying electrochemical reaction mechanism of the ORR within acidic aqueous solutions reveals that the reaction proceeds via a direct four-electron process for all of the 2D-MoS2-SPE variants studied herein, where oxygen is electrochemically favorably reduced to water. The fabricated 2D-MoS2-SPEs are found to exhibit no degradation in the observed achievable current over the course of 1000 repeat scans. The production of such inks and the resultant mass-producible 2D-MoS2-SPEs mitigates the need to modify post hoc an electrode via the drop-casting technique that has been previously shown to result in a loss of achievable current over the course of 1000 repeat scans. The 2D-MoS2-SPEs designed, fabricated, and tested herein could have commercial viability as electrocatalytic fuel cell electrodes because of being economical as a result of their scales of economy and inherent tailorability. The technique utilized herein to produce the 2D-MoS2-SPEs could be adapted for the incorporation of different 2D nanomaterials, resulting in SPEs with the inherent advantages identified above.
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Affiliation(s)
| | - Graham C Smith
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester , Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, U.K
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34
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Croft S, Chauvenet ALM, Smith GC. A systematic approach to estimate the distribution and total abundance of British mammals. PLoS One 2017; 12:e0176339. [PMID: 28658248 PMCID: PMC5489149 DOI: 10.1371/journal.pone.0176339] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 02/23/2017] [Indexed: 11/18/2022] Open
Abstract
Robust policy decisions regarding the protection and management of terrestrial mammals require knowledge of where species are and in what numbers. The last comprehensive review, presenting absolute estimates at a national scale, was published nearly 20 years ago and was largely based on expert opinion. We investigated and propose a systematic data driven approach combing publically available occurrence data with published density estimates to predict species distribution maps and derive total abundance figures for all terrestrial mammals inhabiting Britain. Our findings suggest that the methodology has potential; generally producing plausible predictions consistent with existing information. However, inconsistencies in the availability and recording of data impact the certainty of this output limiting its current application for policy. Restrictions on access and use of occurrence data at a local level produces "data deserts" for which models cannot compensate. This leads to gaps in spatial distribution of species and consequently underestimates abundance. For many species the limited number of geo-referenced densities hampered the extrapolation from habitat suitability to absolute abundance. Even for well-studied species, further density estimates are required. Many density estimates used were pre-1995 and therefore the derived abundance should not be considered a current estimate. To maximise a systematic approach in the future we make the following recommendations: To mitigate the attitudes of a minority of local data providers occurrence records must be submitted to national surveys such as the Mammal Society's Mammal Tracker.Studies are required to estimate density for common species and in areas of low or no abundance.To ensure such studies can be collated and used efficiently we propose a standardised approach reporting density estimates based on the 1km resolution British National Grid, or habitat representative of the 1km square, with digital maps to accompany publications.
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Affiliation(s)
- Simon Croft
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Alienor L. M. Chauvenet
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Graham C. Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
- * E-mail:
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35
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Foster CW, Down MP, Zhang Y, Ji X, Rowley-Neale SJ, Smith GC, Kelly PJ, Banks CE. 3D Printed Graphene Based Energy Storage Devices. Sci Rep 2017; 7:42233. [PMID: 28256602 PMCID: PMC5361393 DOI: 10.1038/srep42233] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 01/06/2017] [Indexed: 12/12/2022] Open
Abstract
3D printing technology provides a unique platform for rapid prototyping of numerous applications due to its ability to produce low cost 3D printed platforms. Herein, a graphene-based polylactic acid filament (graphene/PLA) has been 3D printed to fabricate a range of 3D disc electrode (3DE) configurations using a conventional RepRap fused deposition moulding (FDM) 3D printer, which requires no further modification/ex-situ curing step. To provide proof-of-concept, these 3D printed electrode architectures are characterised both electrochemically and physicochemically and are advantageously applied as freestanding anodes within Li-ion batteries and as solid-state supercapacitors. These freestanding anodes neglect the requirement for a current collector, thus offering a simplistic and cheaper alternative to traditional Li-ion based setups. Additionally, the ability of these devices’ to electrochemically produce hydrogen via the hydrogen evolution reaction (HER) as an alternative to currently utilised platinum based electrodes (with in electrolysers) is also performed. The 3DE demonstrates an unexpectedly high catalytic activity towards the HER (−0.46 V vs. SCE) upon the 1000th cycle, such potential is the closest observed to the desired value of platinum at (−0.25 V vs. SCE). We subsequently suggest that 3D printing of graphene-based conductive filaments allows for the simple fabrication of energy storage devices with bespoke and conceptual designs to be realised.
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Affiliation(s)
- Christopher W Foster
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M15 GD, UK
| | - Michael P Down
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M15 GD, UK
| | - Yan Zhang
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China
| | - Xiaobo Ji
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China
| | - Samuel J Rowley-Neale
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M15 GD, UK
| | - Graham C Smith
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester, Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, UK
| | - Peter J Kelly
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M15 GD, UK
| | - Craig E Banks
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M15 GD, UK
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36
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Budgey R, Learmount J, Smith GC. Simulating control of a focal wildlife outbreak of Echinococcus multilocularis. Vet Parasitol 2017; 237:47-56. [PMID: 28249768 DOI: 10.1016/j.vetpar.2017.02.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 02/14/2017] [Accepted: 02/19/2017] [Indexed: 11/17/2022]
Abstract
The parasitic tapeworm Echinococcus multilocularis is the causative agent of alveolar echinococcosis, a serious zoonotic infection present in Europe that can be fatal. The United Kingdom currently has E. multilocularis free status but the possibility of introduction exists, most likely via an imported or returning dog or other deliberately introduced animal that has not had anthelmintic treatment. We have developed a model to predict the probability of successfully eliminating a focal outbreak of E. multilocularis using a programme of anthelmintic bait distribution. We investigated three different potential control programmes, each with 36 monthly campaigns commencing five, ten or 15 years after disease introduction over an area of 2827km2. We assumed equilibrium disease prevalence of 30%, 40% and 55% based on the range of values reported across Europe. However, for all of these scenarios, equilibrium had not been reached at five to 15 years after introduction and simulated local prevalence values were between 0.5% and 28%. We found that it is possible to eliminate the disease with a 38%-86% success rate if control is started five years after introduction, dropping to 0% to 56% if control is delayed until 15 years after introduction, depending upon the prevalence equilibrium. We have also estimated the costs involved in these programmes to be from €7 to €12 million (2013 prices).
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Affiliation(s)
- Richard Budgey
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom.
| | - Jane Learmount
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom.
| | - Graham C Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom.
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37
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Khan AF, Brownson DAC, Foster CW, Smith GC, Banks CE. Surfactant exfoliated 2D hexagonal Boron Nitride (2D-hBN) explored as a potential electrochemical sensor for dopamine: surfactants significantly influence sensor capabilities. Analyst 2017; 142:1756-1764. [DOI: 10.1039/c7an00323d] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The surfactant utilised in the exfoliated synthesis of 2D hexagonal Boron Nitride (2D-hBN) significantly influences sensor capabilities towards the detection of dopamine.
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Affiliation(s)
- Aamar F. Khan
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Dale A. C. Brownson
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Christopher W. Foster
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
| | - Graham C. Smith
- Faculty of Science and Engineering
- Department of Natural Sciences
- University of Chester
- Chester CH2 4NU
- UK
| | - Craig E. Banks
- Faculty of Science and Engineering
- Manchester Metropolitan University
- Manchester M1 5GD
- UK
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38
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Smith GC, Delahay RJ, McDonald RA, Budgey R. Model of Selective and Non-Selective Management of Badgers (Meles meles) to Control Bovine Tuberculosis in Badgers and Cattle. PLoS One 2016; 11:e0167206. [PMID: 27893809 PMCID: PMC5125688 DOI: 10.1371/journal.pone.0167206] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 11/10/2016] [Indexed: 11/21/2022] Open
Abstract
Bovine tuberculosis (bTB) causes substantial economic losses to cattle farmers and taxpayers in the British Isles. Disease management in cattle is complicated by the role of the European badger (Meles meles) as a host of the infection. Proactive, non-selective culling of badgers can reduce the incidence of disease in cattle but may also have negative effects in the area surrounding culls that have been associated with social perturbation of badger populations. The selective removal of infected badgers would, in principle, reduce the number culled, but the effects of selective culling on social perturbation and disease outcomes are unclear. We used an established model to simulate non-selective badger culling, non-selective badger vaccination and a selective trap and vaccinate or remove (TVR) approach to badger management in two distinct areas: South West England and Northern Ireland. TVR was simulated with and without social perturbation in effect. The lower badger density in Northern Ireland caused no qualitative change in the effect of management strategies on badgers, although the absolute number of infected badgers was lower in all cases. However, probably due to differing herd density in Northern Ireland, the simulated badger management strategies caused greater variation in subsequent cattle bTB incidence. Selective culling in the model reduced the number of badgers killed by about 83% but this only led to an overall benefit for cattle TB incidence if there was no social perturbation of badgers. We conclude that the likely benefit of selective culling will be dependent on the social responses of badgers to intervention but that other population factors including badger and cattle density had little effect on the relative benefits of selective culling compared to other methods, and that this may also be the case for disease management in other wild host populations.
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Affiliation(s)
- Graham C. Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Richard J. Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
| | - Robbie A. McDonald
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Penryn, Cornwall, United Kingdom
| | - Richard Budgey
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, United Kingdom
- * E-mail:
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39
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Waugh DG, Hussain I, Lawrence J, Smith GC, Cosgrove D, Toccaceli C. In vitro mesenchymal stem cell response to a CO2 laser modified polymeric material. Mater Sci Eng C Mater Biol Appl 2016; 67:727-736. [PMID: 27287173 DOI: 10.1016/j.msec.2016.05.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 04/21/2016] [Accepted: 05/15/2016] [Indexed: 11/25/2022]
Abstract
With an ageing world population it is becoming significantly apparent that there is a need to produce implants and platforms to manipulate stem cell growth on a pharmaceutical scale. This is needed to meet the socio-economic demands of many countries worldwide. This paper details one of the first ever studies in to the manipulation of stem cell growth on CO2 laser surface treated nylon 6,6 highlighting its potential as an inexpensive platform to manipulate stem cell growth on a pharmaceutical scale. Through CO2 laser surface treatment discrete changes to the surfaces were made. That is, the surface roughness of the nylon 6,6 was increased by up to 4.3μm, the contact angle was modulated by up to 5° and the surface oxygen content increased by up to 1atom %. Following mesenchymal stem cell growth on the laser treated samples, it was identified that CO2 laser surface treatment gave rise to an enhanced response with an increase in viable cell count of up to 60,000cells/ml when compared to the as-received sample. The effect of surface parameters modified by the CO2 laser surface treatment on the mesenchymal stem cell response is also discussed along with potential trends that could be identified to govern the mesenchymal stem cell response.
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Affiliation(s)
- D G Waugh
- Laser Engineering and Manufacturing Research Centre, Faculty of Science and Engineering, University of Chester, Chester CH1 4BJ, UK.
| | - I Hussain
- School of Life Sciences, Brayford Pool, University of Lincoln, Lincoln LN6 7TS, UK
| | - J Lawrence
- Laser Engineering and Manufacturing Research Centre, Faculty of Science and Engineering, University of Chester, Chester CH1 4BJ, UK
| | - G C Smith
- Laser Engineering and Manufacturing Research Centre, Faculty of Science and Engineering, University of Chester, Chester CH1 4BJ, UK
| | - D Cosgrove
- School of Life Sciences, Brayford Pool, University of Lincoln, Lincoln LN6 7TS, UK
| | - C Toccaceli
- Laser Engineering and Manufacturing Research Centre, Faculty of Science and Engineering, University of Chester, Chester CH1 4BJ, UK
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40
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Khan AF, Randviir EP, Brownson DAC, Ji X, Smith GC, Banks CE. 2D Hexagonal Boron Nitride (2D-hBN) Explored as a Potential Electrocatalyst for the Oxygen Reduction Reaction. ELECTROANAL 2016. [DOI: 10.1002/elan.201600462] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Aamar F. Khan
- Faculty of Science and Engineering; Manchester Metropolitan University; Chester Street Manchester M1 5GD UK
| | - Edward P. Randviir
- Faculty of Science and Engineering; Manchester Metropolitan University; Chester Street Manchester M1 5GD UK
| | - Dale A. C. Brownson
- Faculty of Science and Engineering; Manchester Metropolitan University; Chester Street Manchester M1 5GD UK
| | - Xiaobo Ji
- College of Chemistry and Chemical Engineering; Central South University; Changsha 410083 PR China
| | - Graham C. Smith
- Faculty of Science and Engineering; Department of Natural Sciences; University of Chester; Thornton Science Park, Pool Lane, Ince Chester CH2 4NU UK
| | - Craig E. Banks
- Faculty of Science and Engineering; Manchester Metropolitan University; Chester Street Manchester M1 5GD UK
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41
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Khan AF, Brownson DAC, Randviir EP, Smith GC, Banks CE. 2D Hexagonal Boron Nitride (2D-hBN) Explored for the Electrochemical Sensing of Dopamine. Anal Chem 2016; 88:9729-9737. [PMID: 27659497 DOI: 10.1021/acs.analchem.6b02638] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Crystalline 2D hexagonal boron nitride (2D-hBN) nanosheets are explored as a potential electrocatalyst toward the electroanalytical sensing of dopamine (DA). The 2D-hBN nanosheets are electrically wired via a drop-casting modification process onto a range of commercially available carbon supporting electrodes, including glassy carbon (GC), boron-doped diamond (BDD), and screen-printed graphitic electrodes (SPEs). 2D-hBN has not previously been explored toward the electrochemical detection/electrochemical sensing of DA. We critically evaluate the potential electrocatalytic performance of 2D-hBN modified electrodes, the effect of supporting carbon electrode platforms, and the effect of "mass coverage" (which is commonly neglected in the 2D material literature) toward the detection of DA. The response of 2D-hBN modified electrodes is found to be largely dependent upon the interaction between 2D-hBN and the underlying supporting electrode material. For example, in the case of SPEs, modification with 2D-hBN (324 ng) improves the electrochemical response, decreasing the electrochemical oxidation potential of DA by ∼90 mV compared to an unmodified SPE. Conversely, modification of a GC electrode with 2D-hBN (324 ng) resulted in an increased oxidation potential of DA by ∼80 mV when compared to the unmodified electrode. We explore the underlying mechanisms of the aforementioned examples and infer that electrode surface interactions and roughness factors are critical considerations. 2D-hBN is utilized toward the sensing of DA in the presence of the common interferents ascorbic acid (AA) and uric acid (UA). 2D-hBN is found to be an effective electrocatalyst in the simultaneous detection of DA and UA at both pH 5.0 and 7.4. The peak separations/resolution between DA and UA increases by ∼70 and 50 mV (at pH 5.0 and 7.4, respectively, when utilizing 108 ng of 2D-hBN) compared to unmodified SPEs, with a particularly favorable response evident in pH 5.0, giving rise to a significant increase in the peak current of DA. The limit of detection (3σ) is found to correspond to 0.65 μM for DA in the presence of UA. However, it is not possible to deconvolute the simultaneous detection of DA and AA. The observed electrocatalytic effect at 2D-hBN has not previously been reported in the literature when supported upon carbon or any other electrode. We provide valuable insights into the modifier-substrate interactions of this material, essential for those designing, fabricating, and consequently performing electrochemical experiments utilizing 2D-hBN and related 2D materials.
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Affiliation(s)
- Aamar F Khan
- Faculty of Science and Engineering, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
| | - Dale A C Brownson
- Faculty of Science and Engineering, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
| | - Edward P Randviir
- Faculty of Science and Engineering, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
| | - Graham C Smith
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester , Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, U.K
| | - Craig E Banks
- Faculty of Science and Engineering, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
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42
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Rowley-Neale SJ, Fearn JM, Brownson DAC, Smith GC, Ji X, Banks CE. 2D molybdenum disulphide (2D-MoS2) modified electrodes explored towards the oxygen reduction reaction. Nanoscale 2016; 8:14767-14777. [PMID: 27448174 DOI: 10.1039/c6nr04073j] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Two-dimensional molybdenum disulphide nanosheets (2D-MoS2) have proven to be an effective electrocatalyst, with particular attention being focused on their use towards increasing the efficiency of the reactions associated with hydrogen fuel cells. Whilst the majority of research has focused on the Hydrogen Evolution Reaction (HER), herein we explore the use of 2D-MoS2 as a potential electrocatalyst for the much less researched Oxygen Reduction Reaction (ORR). We stray from literature conventions and perform experiments in 0.1 M H2SO4 acidic electrolyte for the first time, evaluating the electrochemical performance of the ORR with 2D-MoS2 electrically wired/immobilised upon several carbon based electrodes (namely; Boron Doped Diamond (BDD), Edge Plane Pyrolytic Graphite (EPPG), Glassy Carbon (GC) and Screen-Printed Electrodes (SPE)) whilst exploring a range of 2D-MoS2 coverages/masses. Consequently, the findings of this study are highly applicable to real world fuel cell applications. We show that significant improvements in ORR activity can be achieved through the careful selection of the underlying/supporting carbon materials that electrically wire the 2D-MoS2 and utilisation of an optimal mass of 2D-MoS2. The ORR onset is observed to be reduced to ca. +0.10 V for EPPG, GC and SPEs at 2D-MoS2 (1524 ng cm(-2) modification), which is far closer to Pt at +0.46 V compared to bare/unmodified EPPG, GC and SPE counterparts. This report is the first to demonstrate such beneficial electrochemical responses in acidic conditions using a 2D-MoS2 based electrocatalyst material on a carbon-based substrate (SPEs in this case). Investigation of the beneficial reaction mechanism reveals the ORR to occur via a 4 electron process in specific conditions; elsewhere a 2 electron process is observed. This work offers valuable insights for those wishing to design, fabricate and/or electrochemically test 2D-nanosheet materials towards the ORR.
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Affiliation(s)
- Samuel J Rowley-Neale
- Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
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McDonald JL, Bailey T, Delahay RJ, McDonald RA, Smith GC, Hodgson DJ. Demographic buffering and compensatory recruitment promotes the persistence of disease in a wildlife population. Ecol Lett 2016; 19:443-9. [PMID: 26868206 PMCID: PMC4790914 DOI: 10.1111/ele.12578] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 09/30/2015] [Accepted: 01/04/2016] [Indexed: 11/30/2022]
Abstract
Demographic buffering allows populations to persist by compensating for fluctuations in vital rates, including disease‐induced mortality. Using long‐term data on a badger (Meles meles Linnaeus, 1758) population naturally infected with Mycobacterium bovis, we built an integrated population model to quantify impacts of disease, density and environmental drivers on survival and recruitment. Badgers exhibit a slow life‐history strategy, having high rates of adult survival with low variance, and low but variable rates of recruitment. Recruitment exhibited strong negative density‐dependence, but was not influenced by disease, while adult survival was density independent but declined with increasing prevalence of diseased individuals. Given that reproductive success is not depressed by disease prevalence, density‐dependent recruitment of cubs is likely to compensate for disease‐induced mortality. This combination of slow life history and compensatory recruitment promotes the persistence of a naturally infected badger population and helps to explain the badger's role as a persistent reservoir of M. bovis.
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Affiliation(s)
- Jenni L McDonald
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, TR10 9FE, UK
| | - Trevor Bailey
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, Devon, EX4 4QF, UK
| | - Richard J Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK
| | - Robbie A McDonald
- Environment and Sustainability Institute, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, TR10 9FE, UK
| | - Graham C Smith
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK
| | - Dave J Hodgson
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, TR10 9FE, UK
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44
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McDonald JL, Smith GC, McDonald RA, Delahay RJ, Hodgson D. Mortality trajectory analysis reveals the drivers of sex-specific epidemiology in natural wildlife-disease interactions. Proc Biol Sci 2015; 281:rspb.2014.0526. [PMID: 25056621 PMCID: PMC4123697 DOI: 10.1098/rspb.2014.0526] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
In animal populations, males are commonly more susceptible to disease-induced mortality than females. However, three competing mechanisms can cause this sex bias: weak males may simultaneously be more prone to exposure to infection and mortality; being ‘male’ may be an imperfect proxy for the underlying driver of disease-induced mortality; or males may experience increased severity of disease-induced effects compared with females. Here, we infer the drivers of sex-specific epidemiology by decomposing fixed mortality rates into mortality trajectories and comparing their parameters. We applied Bayesian survival trajectory analysis to a 22-year longitudinal study of a population of badgers (Meles meles) naturally infected with bovine tuberculosis (bTB). At the point of infection, infected male and female badgers had equal mortality risk, refuting the hypothesis that acquisition of infection occurs in males with coincidentally high mortality. Males and females exhibited similar levels of heterogeneity in mortality risk, refuting the hypothesis that maleness is only a proxy for disease susceptibility. Instead, sex differences were caused by a more rapid increase in male mortality rates following infection. Males are indeed more susceptible to bTB, probably due to immunological differences between the sexes. We recommend this mortality trajectory approach for the study of infection in animal populations.
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Affiliation(s)
- Jennifer L McDonald
- Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall TR10 9EZ, UK
| | - Graham C Smith
- National Wildlife Management Centre, Animal Health and Veterinary Laboratories Agency, Sand Hutton, York YO41 1LZ, UK
| | - Robbie A McDonald
- Environment and Sustainability Institute, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall TR10 9EZ, UK
| | - Richard J Delahay
- National Wildlife Management Centre, Animal Health and Veterinary Laboratories Agency, Sand Hutton, York YO41 1LZ, UK
| | - Dave Hodgson
- Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall TR10 9EZ, UK
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Rowley-Neale SJ, Brownson DAC, Smith GC, Sawtell DAG, Kelly PJ, Banks CE. 2D nanosheet molybdenum disulphide (MoS2) modified electrodes explored towards the hydrogen evolution reaction. Nanoscale 2015; 7:18152-68. [PMID: 26478468 DOI: 10.1039/c5nr05164a] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We explore the use of two-dimensional (2D) MoS2 nanosheets as an electrocatalyst for the Hydrogen Evolution Reaction (HER). Using four commonly employed commercially available carbon based electrode support materials, namely edge plane pyrolytic graphite (EPPG), glassy carbon (GC), boron-doped diamond (BDD) and screen-printed graphite electrodes (SPE), we critically evaluate the reported electrocatalytic performance of unmodified and MoS2 modified electrodes towards the HER. Surprisingly, current literature focuses almost exclusively on the use of GC as an underlying support electrode upon which HER materials are immobilised. 2D MoS2 nanosheet modified electrodes are found to exhibit a coverage dependant electrocatalytic effect towards the HER. Modification of the supporting electrode surface with an optimal mass of 2D MoS2 nanosheets results in a lowering of the HER onset potential by ca. 0.33, 0.57, 0.29 and 0.31 V at EPPG, GC, SPE and BDD electrodes compared to their unmodified counterparts respectively. The lowering of the HER onset potential is associated with each supporting electrode's individual electron transfer kinetics/properties and is thus distinct. The effect of MoS2 coverage is also explored. We reveal that its ability to catalyse the HER is dependent on the mass deposited until a critical mass of 2D MoS2 nanosheets is achieved, after which its electrocatalytic benefits and/or surface stability curtail. The active surface site density and turn over frequency for the 2D MoS2 nanosheets is determined, characterised and found to be dependent on both the coverage of 2D MoS2 nanosheets and the underlying/supporting substrate. This work is essential for those designing, fabricating and consequently electrochemically testing 2D nanosheet materials for the HER.
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Affiliation(s)
- Samuel J Rowley-Neale
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
| | - Dale A C Brownson
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
| | - Graham C Smith
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester, Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, UK
| | - David A G Sawtell
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
| | - Peter J Kelly
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
| | - Craig E Banks
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK.
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Galdino FE, Smith JP, Kwamou SI, Kampouris DK, Iniesta J, Smith GC, Bonacin JA, Banks CE. Graphite Screen-Printed Electrodes Applied for the Accurate and Reagentless Sensing of pH. Anal Chem 2015; 87:11666-72. [PMID: 26561992 DOI: 10.1021/acs.analchem.5b01236] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A reagentless pH sensor based upon disposable and economical graphite screen-printed electrodes (GSPEs) is demonstrated for the first time. The voltammetric pH sensor utilizes GSPEs which are chemically pretreated to form surface immobilized oxygenated species that, when their redox behavior is monitored, give a Nernstian response over a large pH range (1-13). An excellent experimental correlation is observed between the voltammetric potential and pH over the entire pH range of 1-13 providing a simple approach with which to monitor solution pH. Such a linear response over this dynamic pH range is not usually expected but rather deviation from linearity is encountered at alkaline pH values; absence of this has previously been attributed to a change in the pKa value of surface immobilized groups from that of solution phase species. This non-deviation, which is observed here in the case of our facile produced reagentless pH sensor and also reported in the literature for pH sensitive compounds immobilized upon carbon electrodes/surfaces, where a linear response is observed over the entire pH range, is explained alternatively for the first time. The performance of the GSPE pH sensor is also directly compared with a glass pH probe and applied to the measurement of pH in "real" unbuffered samples where an excellent correlation between the two protocols is observed validating the proposed GSPE pH sensor.
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Affiliation(s)
- Flávia E Galdino
- Institute of Chemistry, University of Campinas-UNICAMP , P.O. Box 6154, 13083-970, Campinas, São Paulo Brazil.,Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
| | - Jamie P Smith
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
| | - Sophie I Kwamou
- Université Paris-Est Créteil-Val de Marne , Faculté des Sciences et Technologie, 61 Avenue du Général de Gaulle, 94010 Créteil Cedex France
| | - Dimitrios K Kampouris
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
| | - Jesus Iniesta
- Physical Chemistry Department and Institute of Electrochemistry, University of Alicante ,03690, San Vicente del Raspeig, Alicante Spain
| | - Graham C Smith
- Faculty of Science and Engineering, Department of Natural Sciences, University of Chester Thornton Science Park, Pool Lane, Ince, Chester CH2 4NU, U.K
| | - Juliano A Bonacin
- Institute of Chemistry, University of Campinas-UNICAMP , P.O. Box 6154, 13083-970, Campinas, São Paulo Brazil
| | - Craig E Banks
- Faculty of Science and Engineering, School of Science and the Environment, Division of Chemistry and Environmental Science, Manchester Metropolitan University , Chester Street, Manchester M1 5GD, U.K
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Moussy C, Atterby H, Griffiths AGF, Allnutt TR, Mathews F, Smith GC, Aegerter JN, Bearhop S, Hosken DJ. Population genetic structure of serotine bats (Eptesicus serotinus) across Europe and implications for the potential spread of bat rabies (European bat lyssavirus EBLV-1). Heredity (Edinb) 2015; 115:83-92. [PMID: 25832817 PMCID: PMC4815494 DOI: 10.1038/hdy.2015.20] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 01/29/2015] [Accepted: 02/12/2015] [Indexed: 11/09/2022] Open
Abstract
Understanding of the movements of species at multiple scales is essential to appreciate patterns of population connectivity and in some cases, the potential for pathogen transmission. The serotine bat (Eptesicus serotinus) is a common and widely distributed species in Europe where it frequently harbours European bat lyssavirus type 1 (EBLV-1), a virus causing rabies and transmissible to humans. In the United Kingdom, it is rare, with a distribution restricted to south of the country and so far the virus has never been found there. We investigated the genetic structure and gene flow of E. serotinus across the England and continental Europe. Greater genetic structuring was found in England compared with continental Europe. Nuclear data suggest a single population on the continent, although further work with more intensive sampling is required to confirm this, while mitochondrial sequences indicate an east-west substructure. In contrast, three distinct populations were found in England using microsatellite markers, and mitochondrial diversity was very low. Evidence of nuclear admixture indicated strong male-mediated gene flow among populations. Differences in connectivity could contribute to the high viral prevalence on the continent in contrast with the United Kingdom. Although the English Channel was previously thought to restrict gene flow, our data indicate relatively frequent movement from the continent to England highlighting the potential for movement of EBLV-1 into the United Kingdom.
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Affiliation(s)
- C Moussy
- Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Cornwall, UK
| | - H Atterby
- Food and Environment Research Agency, York, UK
| | - A G F Griffiths
- Environment and Sustainability Institute, University of Exeter, Cornwall Campus, Cornwall, UK
| | - T R Allnutt
- Food and Environment Research Agency, York, UK
- CSIRO, Werribee, Victoria, Australia
| | - F Mathews
- Hatherly Laboratories, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - G C Smith
- National Wildlife Management Centre, Animal Health and Veterinary Laboratories Agency (AHVLA), York, UK
| | - J N Aegerter
- National Wildlife Management Centre, Animal Health and Veterinary Laboratories Agency (AHVLA), York, UK
| | - S Bearhop
- Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Cornwall, UK
| | - D J Hosken
- Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Cornwall, UK
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Kalter SS, Heberling RL, Helmke RJ, Panigel M, Smith GC, Kraemer DC, Hellman A, Fowler AK, Strickland JE. A comparative study on the presence of C-type viral particles in placentas from primates and other animals. Bibl Haematol 2015:391-401. [PMID: 169817 DOI: 10.1159/000397557] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
C-type particles are found in human, baboon, marmoset, rhesus, patas, and cynomolgus monkeys. A cebus monkey and two chimpanzee placentas have failed thus far to show the presence of these particles. Of the nonprimate tissues examined one mouse and one guinea pig placenta were positive whereas a rabbit placenta was negative. Variations in number of particles present in tissues as well as number of animals of a given species containing particles are noted. The isolation of foamyviruses from placenta cultures makes critical evaluation and interpretation of findings imperative. Several considerations suggest that the presence of foamyviruses is coincidental.
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Affiliation(s)
- Graham C Smith
- Children's Kidney Centre, University Hospital of Wales, Cardiff CF14 4XW, UK
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50
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Chauvenet ALM, Hutson AM, Smith GC, Aegerter JN. Demographic variation in the U.K. serotine bat: filling gaps in knowledge for management. Ecol Evol 2015; 4:3820-9. [PMID: 25614796 PMCID: PMC4301045 DOI: 10.1002/ece3.1174] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 06/19/2014] [Accepted: 07/02/2014] [Indexed: 11/26/2022] Open
Abstract
Species of conservation concern, or those in conflict with man, are most efficiently managed with an understanding of their population dynamics. European bats exemplify the need for successful and cost-effective management for both reasons, often simultaneously. Across Europe, bats are protected, and the concept of Favourable Conservation Status (FCS) is used as a key tool for the assessment and licensing of disruptive actions to populations. However, for efficient decision-making, this assessment requires knowledge on the demographic rates and long-term dynamics of populations. We used capture–mark–recapture to describe demographic rates for the Serotine bat (Eptesicus serotinus) at two sites in England and investigate the transition rates between three stages: juveniles, immatures, and breeders. We then use these rates in an individual-based population dynamics model to investigate the expected trajectories for both populations. Our results demonstrate for the first time the presence and scale of temporal variation in this species' demography. We describe the lengthy prereproductive period (3.5 years) that female Serotines experience. Finally, we show how site-specific variation in demographic rates can produce divergent population trajectories. Effective management of European bat populations can be achieved through the understanding of life histories, and local demographic rates and population dynamics, in order to anticipate the presence of source and sink sites in the landscape. Using the Serotine bat in England, we show that these can be obtained from rigorous and systematic studies of long-term demographic datasets.
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Affiliation(s)
- Alienor L M Chauvenet
- National Wildlife Management Centre, Animal Health and Veterinary Laboratory Agency Sand Hutton, York, YO41 1LZ, U.K
| | - Anthony M Hutson
- Station Road, Winkfield, Plumpton Green, East Sussex, BN7 3BU, U.K
| | - Graham C Smith
- National Wildlife Management Centre, Animal Health and Veterinary Laboratory Agency Sand Hutton, York, YO41 1LZ, U.K
| | - James N Aegerter
- National Wildlife Management Centre, Animal Health and Veterinary Laboratory Agency Sand Hutton, York, YO41 1LZ, U.K
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