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Gains JE, Patel A, Chang YC, Mandeville HC, Smyth G, Stacey C, Talbot J, Wheatley K, Gaze MN. A Randomised Phase II Trial to Evaluate the Feasibility of Radiotherapy Dose Escalation, Facilitated by Intensity-Modulated Arc Radiotherapy Techniques, in High-Risk Neuroblastoma. Clin Oncol (R Coll Radiol) 2024; 36:e154-e162. [PMID: 38553363 DOI: 10.1016/j.clon.2024.03.004] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/17/2024] [Accepted: 03/08/2024] [Indexed: 05/06/2024]
Abstract
BACKGROUND AND PURPOSE For high-risk neuroblastoma, planning target volume coverage is often compromised to respect adjacent kidney tolerance. This trial investigated whether intensity-modulated arc radiotherapy techniques (IMAT) could facilitate dose escalation better than conventional techniques. MATERIALS AND METHODS Children with high-risk abdominal neuroblastoma referred for radiotherapy to the primary tumour site and involved regional lymph nodes were randomised to receive either standard dose (21 Gy in 14 fractions) or escalated dose (36 Gy in 24 fractions) radiotherapy. Dual planning with both a conventional anterior-posterior parallel opposed pair radiotherapy technique and an IMAT technique was performed. The quality of target volume and organ-at-risk delineation, and dosimetric plans, were externally reviewed. Dosimetric parameters were used to judge the superior technique for treatment. This feasibility trial was not powered to detect improvement in outcome with dose escalation. RESULTS Between 2017 and 2020, 50 patients were randomised and dual-planned. The IMAT technique was judged more favourable in 48 patients. In all patients randomised to receive 36 Gy, IMAT would have permitted delivery of the full dose (median D50% 36.0 Gy, inter-quartile range 36.0-36.1 Gy) to the target volume, whereas dose compromise would have been required with conventional planning (median D50% 35.6 Gy, inter-quartile range 28.7-35.9 Gy). CONCLUSION IMAT facilitates safe dose escalation to 36 Gy in patients receiving radiotherapy for neuroblastoma. The value of dose escalation is now being evaluated in a current prospective phase III randomised trial.
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Affiliation(s)
- J E Gains
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, UK
| | - A Patel
- Cancer Research UK Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | - Yen-Ch'ing Chang
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, UK
| | - H C Mandeville
- Department of Radiotherapy, The Royal Marsden NHS Foundation Trust, Sutton, UK
| | - G Smyth
- National Radiotherapy Trials Quality Assurance Group, The Royal Marsden NHS Foundation Trust, Sutton, UK
| | - C Stacey
- Radiotherapy Physics Group, University College London Hospitals NHS Foundation Trust, London, UK
| | - J Talbot
- Department of Radiotherapy, The Royal Marsden NHS Foundation Trust, Sutton, UK
| | - K Wheatley
- Cancer Research UK Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | - M N Gaze
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, UK. https://twitter.com/@MarkGaze
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Barrow S, Talbot J, Kindelan S, Walker E. The role of CBCT in paediatric dentoalveolar trauma: A service evaluation. Int J Paediatr Dent 2023; 33 Suppl 2:66-68. [PMID: 37665153 DOI: 10.1111/ipd.13111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Affiliation(s)
- S Barrow
- Paediatric Dentistry and Dental and Maxillofacial Radiology, Leeds Dental Institute, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - J Talbot
- Paediatric Dentistry and Dental and Maxillofacial Radiology, Leeds Dental Institute, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - S Kindelan
- Paediatric Dentistry and Dental and Maxillofacial Radiology, Leeds Dental Institute, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - E Walker
- Paediatric Dentistry and Dental and Maxillofacial Radiology, Leeds Dental Institute, Leeds Teaching Hospitals NHS Trust, Leeds, UK
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Talbot J, Højsgaard Chow H, Holm Hansen R, von Essen MR, Sellebjerg F. Immunological effects of dimethyl fumarate treatment in blood and CSF of patients with primary progressive MS. J Neuroimmunol 2021; 361:577756. [PMID: 34739914 DOI: 10.1016/j.jneuroim.2021.577756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 08/16/2021] [Revised: 09/10/2021] [Accepted: 10/17/2021] [Indexed: 01/22/2023]
Abstract
Dimethyl fumarate is an efficient therapy used widely in patients with relapsing-remitting multiple sclerosis (RRMS). However, lacking effect of treatment has recently been reported in patients with primary progressive MS (PPMS) (Højsgaard Chow et al., 2021). In order to further analyze the immunological treatment response we investigated the systemic and intrathecal immunological effects of dimethyl fumarate (DMF) treatment in 50 patients with PPMS who participated in a 48-week randomized controlled trial with dimethyl fumarate vs placebo. We found substantial systemic immunomodulatory effects of DMF treatment comparable with those observed in patients with RRMS. However, intrathecal effects were limited and restricted to CD4+ T cells presumably resulting in higher concentrations of intrathecal IL-7.
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Affiliation(s)
- J Talbot
- Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Glostrup, Denmark.
| | - H Højsgaard Chow
- Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Glostrup, Denmark
| | - R Holm Hansen
- Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Glostrup, Denmark
| | - M Rode von Essen
- Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Glostrup, Denmark
| | - F Sellebjerg
- Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital - Rigshospitalet, Glostrup, Denmark; Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
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Talbot J, Stuckey R, Crawford L, Weatherby S, Mullin S. Improvements in pain, medication use and quality of life in onabotulinumtoxinA-resistant chronic migraine patients following erenumab treatment - real world outcomes. J Headache Pain 2021; 22:5. [PMID: 33421995 PMCID: PMC7797151 DOI: 10.1186/s10194-020-01214-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [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: 10/09/2020] [Accepted: 12/26/2020] [Indexed: 12/21/2022] Open
Abstract
Background The CGRP antagonists offer a novel therapeutic approach in migraine. Their utility in patients with severe forms of chronic migraine is a subject of particular interest. We present outcomes of 9 months of erenumab treatment in a cohort of patients with difficult-to-control chronic migraine, all of whom had prior unsatisfactory response to onabotulinumtoxinA. Methods We offered erenumab to 98 patients with a prior unsatisfactory response to onabotulinumtoxinA. Eighty of 98 had trialled greater occipital nerve injections (82%), 32/98 peripheral neurostimulation (33%) and 18/98 intravenous dihydroergotamine (18%). Thirty eight of 98 (39%) met the definition of triptan overuse and 43/98 (44%) analgesic overuse. All patients met the EHF criteria for ‘resistant migraine’. Outcome measures (recorded monthly) included days with headache limiting activities of daily living (“red”), not limiting (“amber”), headache free (“green”), and requiring triptans or other analgesics. Quality of life scores - headache impact test 6 (HIT-6), patient health questionnaire 9 (PHQ-9) and pain disability index (PDI) - were also measured. Results Mean number of red days improved by − 6.4 days (SE 0.67, 95%CI − 7.7 to − 5.1, p=0.001) at 3 months; − 6.8 days (SE 0.96, 95%CI − 8.80 to − 4.9, p=0.001) at 6 months and − 6.5 days (SE 0.86, 95%CI − 8.3 to − 4.8, p=0.001) at 9 months. Repeated measures ANOVA confirmed improvements in the number of red (p=0.001), green (p=0.001), triptan (p=0.001) and painkiller days (p=0.001) as well as scores of the HIT-6 (p=0.001), PHQ-9 (p=0.001), and PDI (p=0.001) across the duration of study. Conclusion We observed improvements in pain, medication use and quality of life in onabotulinumtoxinA-resistant chronic migraine patients following erenumab treatment. Supplementary Information The online version contains supplementary material available at 10.1186/s10194-020-01214-2.
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Affiliation(s)
- J Talbot
- Southwest Neurology Audit and Research group (SoNAR), Department of Neurology, Derriford Hospital, Plymouth, PL6 8DH, UK.
| | - R Stuckey
- Southwest Neurology Audit and Research group (SoNAR), Department of Neurology, Derriford Hospital, Plymouth, PL6 8DH, UK
| | - L Crawford
- Southwest Neurology Audit and Research group (SoNAR), Department of Neurology, Derriford Hospital, Plymouth, PL6 8DH, UK
| | - S Weatherby
- Southwest Neurology Audit and Research group (SoNAR), Department of Neurology, Derriford Hospital, Plymouth, PL6 8DH, UK
| | - S Mullin
- Peninsula Medical School, University of Plymouth, Plymouth, UK.,UCL Queen Square Institute of Neurology, University College London, London, UK
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Martin LJ, Chen Y, Serrano-Lomelin J, Talbot J, Yasui Y. Higher levels of social and material deprivation are associated with higher rates of influenza-like illness-related emergency department visits: Edmonton, Alberta, 2004-2014. Public Health 2020; 189:117-122. [PMID: 33221645 DOI: 10.1016/j.puhe.2020.06.039] [Citation(s) in RCA: 4] [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: 10/03/2019] [Revised: 04/05/2020] [Accepted: 06/19/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVES Neighbourhood-level deprivation is associated with hospitalization related to respiratory infections; however, hospitalizations exclude many who seek care with less severe respiratory illnesses. Another major seasonal contributor to respiratory illness-associated healthcare burdens are influenza-like illness (ILI)-related emergency department (ED) visits. We investigated associations between area-level social and material deprivation and ILI-related ED use. STUDY DESIGN This is a retrospective ecological study. METHODS We linked ILI-related ED visit data (2004-2014) for Edmonton, Alberta to a Canadian area-level material and social deprivation index, categorizing deprivation into quintiles. Using a multivariable Poisson model with log population as the offset, we modelled the relationship between visit rates and material and social deprivation adjusting for week and season, age, sex and the interaction between age and sex. RESULTS We included 67,585 ILI-related ED visits, representing 1075.5 (95% confidence interval (CI) = 1067.4-1083.6) visits per 100,000 person-years. ILI-related visit rates increased as each of material and social deprivation increased; increases were slightly greater for material deprivation. Comparing the most deprived quintile to the least deprived quintile: for material deprivation, ILI-related ED visit rates were two times higher (rate ratio (RR) = 2.00, 95% CI = 1.96-2.05); and, for social deprivation, one-and-a-half times higher (RR = 1.47, 95% CI = 1.44-1.51). CONCLUSIONS Higher area-level material and social deprivation were associated with higher ILI-related ED visit rates. These findings can be used to identify areas that may need additional public health and healthcare resources and to improve targeting of prevention strategies. Understanding differentials in healthcare use such as this may be especially relevant to ensuring equity of outcomes for pandemic preparedness planning.
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Affiliation(s)
- L J Martin
- School of Public Health, University of Alberta, 11405 - 87 Ave, Edmonton, T6G 1C9, Alberta, Canada.
| | - Y Chen
- School of Public Health, University of Alberta, 11405 - 87 Ave, Edmonton, T6G 1C9, Alberta, Canada
| | - J Serrano-Lomelin
- School of Public Health, University of Alberta, 11405 - 87 Ave, Edmonton, T6G 1C9, Alberta, Canada
| | - J Talbot
- School of Public Health, University of Alberta, 11405 - 87 Ave, Edmonton, T6G 1C9, Alberta, Canada
| | - Y Yasui
- School of Public Health, University of Alberta, 11405 - 87 Ave, Edmonton, T6G 1C9, Alberta, Canada; Department of Epidemiology and Cancer Control, St. Jude Children's Research Hospital, Memphis, TN, USA.
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De Vleeschouwer F, Baron S, Cloy JM, Enrico M, Ettler V, Fagel N, Kempter H, Kylander M, Li C, Longman J, Martinez-Cortizas A, Marx S, Mattielli N, Mighall T, Nieminen TM, Piotrowska N, Pontevedra-Pombal X, Pratte S, Renson V, Shotyk W, Shuttleworth E, Sikorski J, Stromsoe N, Talbot J, von Scheffer C, Weiss D, Zaccone C, Le Roux G. Comment on: "A novel approach to peatlands as archives of total cumulative spatial pollution loads from atmospheric deposition of airborne elements complementary to EMEP data: Priority pollutants (Pb, Cd, Hg)" by Ewa Miszczak, Sebastian Stefaniak, Adam Michczyński, Eiliv Steinnes and Irena Twardowska. Sci Total Environ 2020; 737:138699. [PMID: 32376094 DOI: 10.1016/j.scitotenv.2020.138699] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/06/2020] [Accepted: 04/12/2020] [Indexed: 06/11/2023]
Abstract
A recent paper by Miszczak et al. (2020) examines metal contamination of mires in Poland and Norway. The authors conclude that lead (Pb) records in ombrotrophic peatlands cannot be used to reconstruct the chronological history of anthropogenic activities due to post-depositional mobility of the metal. We contest this general conclusion which stands in contrast with a significant body of literature demonstrating that Pb is largely immobile in the vast majority of ombrotrophic peatlands. Our aim is to reaffirm the crucial contribution that peat records have made to our knowledge of atmospheric Pb contamination. In addition, we reiterate the necessity of following established protocols to produce reliable records of anthropogenic Pb contamination in environmental archives.
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Affiliation(s)
- F De Vleeschouwer
- Instituto Franco-Argentino para el Estudio del Clima y sus Impactos (UMI IFAECI/CNRS-CONICET-UBA-IRD), Argentina.
| | - S Baron
- Laboratoire TRACES (CNRS, Université de Toulouse), France
| | - J M Cloy
- Scotland's Rural College, Edinburgh, UK
| | - M Enrico
- Harvard John A. Paulson School of Engineering and Applied Science, Harvard University, Cambridge, MA, USA
| | - V Ettler
- Charles University, Faculty of Science, Prague, Czech Republic
| | - N Fagel
- AGEs, Département de Géologie, Université de Liège, Belgium
| | - H Kempter
- Welzheimer Str. 14, D-71566 Althuette, Germany
| | - M Kylander
- Department of Geological Sciences and the Bolin Centre for Climate Research, Stockholm University, Sweden
| | - C Li
- Geoscience Environnement Toulouse (CNRS-UPS-IRD-CNAP-CNES), France
| | - J Longman
- School of Geography and the Environment, University of Oxford, UK
| | | | - S Marx
- GeoQuEST Research Centre, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Australia
| | - N Mattielli
- Laboratoire G-Time, Université Libre de Bruxelles, Belgium
| | - T Mighall
- School of Geosciences, University of Aberdeen, UK
| | - T M Nieminen
- Natural Resources Institute Finland Luke, Helsinki, Finland
| | - N Piotrowska
- Silesian University of Technology, Institute of Physics-CSE, GADAM Center, Gliwice, Poland
| | | | - S Pratte
- Department of Geography, School of Earth Sciences, Zhejiang University, Hangzhou, China
| | - V Renson
- Research Reactor, University of Missouri, USA
| | - W Shotyk
- Department of Renewable Resources, University of Alberta, Edmonton, Canada
| | | | - J Sikorski
- Silesian University of Technology, Institute of Physics-CSE, GADAM Center, Gliwice, Poland
| | - N Stromsoe
- College of Engineering, IT and Environment, Charles Darwin University, Australia
| | - J Talbot
- Département de Géographie, Université de Montréal, Canada
| | - C von Scheffer
- Institute for Ecosystem Research, Kiel University, Germany
| | - D Weiss
- Imperial College London, UK; Princeton University, Princeton, USA
| | - C Zaccone
- Department of Biotechnology, University of Verona, Italy
| | - G Le Roux
- Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France
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Csikar J, Vinall-Collier K, Richemond JM, Talbot J, Serban ST, Douglas GVA. Identifying the barriers and facilitators for homeless people to achieve good oral health. Community Dent Health 2019; 36:137-142. [PMID: 31070874 DOI: 10.1922/cdh_4488csikar06] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE A qualitative exploration of the barriers and facilitators for people experiencing homelessness achieving good oral health. PARTICIPANTS Adults using two homeless centres in Leeds. METHODS Focus group discussions were convened with homeless people using support services. Both an inductive and deductive approach to data analysis was taken. Themes were identified and then a framework applied to analysis using Nvivo software. RESULTS Three focus group discussions with 16 participants were conducted with people experiencing homelessness. The barriers identified were insufficient information on local dental services, negative attitudes of oral health professionals, low priority of dental care, anxiety and cost of dental treatments. Facilitators included single dental appointments, accessible dental locations and being treated with respect. CONCLUSIONS Despite the barriers that prevent people experiencing homelessness from maintaining and improving their oral health, the participants were aware that they needed oral healthcare and requested that dental services were made available to them and were accessible in line with their socioeconomic status and needs.
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Affiliation(s)
- J Csikar
- The University of Leeds School of Dentistry.,Public Health England
| | | | | | - J Talbot
- City Healthcare Partnership and Harrogate Hospitals
| | - S T Serban
- The University of Leeds School of Dentistry
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Talbot J, Starr D. Chronic temporomandibular joint pain: A localised benign osteoma and review of the literature. Int J Surg 2018. [DOI: 10.1016/j.ijsu.2018.05.320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Talbot J, Karsai L, Crank S. Rosai-dorfman disease: A rare clinical entity. Case report and review of the literature. Int J Surg 2018. [DOI: 10.1016/j.ijsu.2018.05.321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
We study the "color dynamics" of a hard-disk fluid confined in an annulus, as well as the corresponding hard-sphere system in three dimensions, using event-driven simulation in order to explore the effect of confinement and self-crowding on the search for targets. We compute the mean first-passage times (MFPTs) of red particles transiting from the outer to the inner boundary as well as those of blue particles passing from the inner to the outer boundary for different packing fractions and geometries. In the steady state the reaction rate, defined as the rate of collision of red particles with the inner boundary, is inversely proportional to the sum of the MFPTs. The reaction rate is wall mediated (ballistic) at low densities and diffusion controlled at higher densities and displays a maximum at intermediate densities. At moderate to high densities, the presence of layering has a strong influence on the search process. The numerical results for the reaction rate and MFPTs are compared with a ballistic model at low densities and a Smoluchowski approach with uniform diffusivities at higher densities. We discuss the reasons for the limited validity of the theoretical approaches. The maximum in the reaction rate is qualitatively well rendered by a Bosanquet-like approach that interpolates between the two regimes. Finally, we compute the position-dependent diffusivity from the MFPTs and observe that it is out of phase with the radial density.
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Affiliation(s)
- C Antoine
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4 place Jussieu, 75252 Paris Cedex 05, France
| | - J Talbot
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4 place Jussieu, 75252 Paris Cedex 05, France
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Abstract
Although there are many theoretical studies of the mean first-passage time (MFPT), most neglect the diffusive heterogeneity of real systems. We present exact analytical expressions for the MFPT and residence times of a pointlike particle diffusing in a spherically symmetric d-dimensional heterogeneous system composed of two concentric media with different diffusion coefficients with an absorbing inner boundary (target) and a reflecting outer boundary. By varying the convention, e.g., Itō, Stratonovich, or isothermal, chosen to interpret the overdamped Langevin equation with multiplicative noise describing the diffusion process, we find different predictions and counterintuitive results for the residence time in the outer region and hence for the MFPT, while the residence time in the inner region is independent of the convention. This convention dependence of residence times and the MFPT could provide insights about the heterogeneous diffusion in a cell or in a tumor, or for animal and insect searches inside their home range.
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Affiliation(s)
- G Vaccario
- Laboratoire de Physique Théorique de la Matiére Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4, Place Jussieu, 75252 Paris, Cedex 05, France
| | - C Antoine
- Laboratoire de Physique Théorique de la Matiére Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4, Place Jussieu, 75252 Paris, Cedex 05, France
| | - J Talbot
- Laboratoire de Physique Théorique de la Matiére Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4, Place Jussieu, 75252 Paris, Cedex 05, France
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13
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Au I, Ciurlionis L, Campbell N, Talbot J. Validation of Model Based Patient Specific Quality Assurance (QA) Using Introduced Intentional Errors. Int J Radiat Oncol Biol Phys 2015. [DOI: 10.1016/j.ijrobp.2015.07.2137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
Flow in channel networks may involve a redistribution of flux following the blockage or failure of an individual link. Here we consider a simplified model consisting of N(c) parallel channels conveying a particulate flux. Particles enter these channels according to a homogeneous Poisson process and an individual channel blocks if more than N particles are simultaneously present. The behavior of the composite system depends strongly on how the flux of entering particles is redistributed following a blockage. We consider two cases. In the first, the intensity on each open channel remains constant while in the second the total intensity is evenly redistributed over the open channels. We obtain exact results for arbitrary N(c) and N for a system of independent channels and for arbitrary N(c) and N=1 for coupled channels. For N>1 we present approximate analytical as well as numerical results. Independent channels block at a decreasing rate due to a simple combinatorial effect, while for coupled channels the interval between successive blockages remains constant for N=1 but decreases for N>1. This accelerating cascade is due to the nonlinear dependence of the mean blocking time of a single channel on the entering particle flux that more than compensates for the decrease in the number of active channels.
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Affiliation(s)
- C Barré
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4, place Jussieu, 75252 Paris Cedex 05, France
| | - J Talbot
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4, place Jussieu, 75252 Paris Cedex 05, France
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Barré C, Talbot J, Viot P, Angelani L, Gabrielli A. Generalized model of blockage in particulate flow limited by channel carrying capacity. Phys Rev E Stat Nonlin Soft Matter Phys 2015; 92:032141. [PMID: 26465460 DOI: 10.1103/physreve.92.032141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Indexed: 06/05/2023]
Abstract
We investigate stochastic models of particles entering a channel with a random time distribution. When the number of particles present in the channel exceeds a critical value N, a blockage occurs and the particle flux is definitively interrupted. By introducing an integral representation of the n-particle survival probabilities, we obtain exact expressions for the survival probability, the distribution of the number of particles that pass before failure, the instantaneous flux of exiting particles, and their time correlation. We generalize previous results for N=2 to an arbitrary distribution of entry times and obtain exact solutions for N=3 for a Poisson distribution and partial results for N≥4.
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Affiliation(s)
- C Barré
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4 Place Jussieu, 75252 Paris Cedex 05, France
| | - J Talbot
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4 Place Jussieu, 75252 Paris Cedex 05, France
| | - P Viot
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR 7600, Sorbonne Universités, 4 Place Jussieu, 75252 Paris Cedex 05, France
| | - L Angelani
- Istituto dei Sistemi Complessi (ISC) - CNR, UOS "Sapienza," Department of Physics, University "Sapienza" of Rome, Piazzale Aldo Moro 2, 00185 Rome, Italy
| | - A Gabrielli
- Istituto dei Sistemi Complessi (ISC) - CNR, UOS "Sapienza," Department of Physics, University "Sapienza" of Rome, Piazzale Aldo Moro 2, 00185 Rome, Italy
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Lapworth DJ, Baran N, Stuart ME, Manamsa K, Talbot J. Persistent and emerging micro-organic contaminants in Chalk groundwater of England and France. Environ Pollut 2015; 203:214-225. [PMID: 25882715 DOI: 10.1016/j.envpol.2015.02.030] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [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: 12/11/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 05/25/2023]
Abstract
The Chalk aquifer of Northern Europe is an internationally important source of drinking water and sustains baseflow for surface water ecosystems. The areal distribution of microorganic (MO) contaminants, particularly non-regulated emerging MOs, in this aquifer is poorly understood. This study presents results from a reconnaissance survey of MOs in Chalk groundwater, including pharmaceuticals, personal care products and pesticides and their transformation products, conducted across the major Chalk aquifers of England and France. Data from a total of 345 sites collected during 2011 were included in this study to provide a representative baseline assessment of MO occurrence in groundwater. A suite of 42 MOs were analysed for at each site including industrial compounds (n=16), pesticides (n=14) and pharmaceuticals, personal care and lifestyle products (n=12). Occurrence data is evaluated in relation to land use, aquifer exposure, well depth and depth to groundwater to provide an understanding of vulnerable groundwater settings.
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Affiliation(s)
- D J Lapworth
- British Geological Survey, Maclean Building, Wallingford, Oxfordshire, OX10 8BB, UK.
| | - N Baran
- Bureau de Recherches Géologiques et Minières, 3 Avenue Claude Guillemin, BP 6009, 45060 Orléans, Cedex 2, France
| | - M E Stuart
- British Geological Survey, Maclean Building, Wallingford, Oxfordshire, OX10 8BB, UK
| | - K Manamsa
- British Geological Survey, Maclean Building, Wallingford, Oxfordshire, OX10 8BB, UK
| | - J Talbot
- British Geological Survey, Maclean Building, Wallingford, Oxfordshire, OX10 8BB, UK
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Franca RFO, Vieira SM, Talbot J, Peres RS, Pinto LG, Zamboni DS, Louzada-Junior P, Cunha FQ, Cunha TM. Expression and activity ofNOD1andNOD2/RIPK2signalling in mononuclear cells from patients with rheumatoid arthritis. Scand J Rheumatol 2015. [DOI: 10.3109/03009742.2015.1047403] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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18
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Brienen RJW, Phillips OL, Feldpausch TR, Gloor E, Baker TR, Lloyd J, Lopez-Gonzalez G, Monteagudo-Mendoza A, Malhi Y, Lewis SL, Vásquez Martinez R, Alexiades M, Álvarez Dávila E, Alvarez-Loayza P, Andrade A, Aragão LEOC, Araujo-Murakami A, Arets EJMM, Arroyo L, Aymard C GA, Bánki OS, Baraloto C, Barroso J, Bonal D, Boot RGA, Camargo JLC, Castilho CV, Chama V, Chao KJ, Chave J, Comiskey JA, Cornejo Valverde F, da Costa L, de Oliveira EA, Di Fiore A, Erwin TL, Fauset S, Forsthofer M, Galbraith DR, Grahame ES, Groot N, Hérault B, Higuchi N, Honorio Coronado EN, Keeling H, Killeen TJ, Laurance WF, Laurance S, Licona J, Magnussen WE, Marimon BS, Marimon-Junior BH, Mendoza C, Neill DA, Nogueira EM, Núñez P, Pallqui Camacho NC, Parada A, Pardo-Molina G, Peacock J, Peña-Claros M, Pickavance GC, Pitman NCA, Poorter L, Prieto A, Quesada CA, Ramírez F, Ramírez-Angulo H, Restrepo Z, Roopsind A, Rudas A, Salomão RP, Schwarz M, Silva N, Silva-Espejo JE, Silveira M, Stropp J, Talbot J, ter Steege H, Teran-Aguilar J, Terborgh J, Thomas-Caesar R, Toledo M, Torello-Raventos M, Umetsu RK, van der Heijden GMF, van der Hout P, Guimarães Vieira IC, Vieira SA, Vilanova E, Vos VA, Zagt RJ. Long-term decline of the Amazon carbon sink. Nature 2015; 519:344-8. [PMID: 25788097 DOI: 10.1038/nature14283] [Citation(s) in RCA: 339] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 02/04/2015] [Indexed: 11/09/2022]
Abstract
Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.
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Affiliation(s)
- R J W Brienen
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - O L Phillips
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - T R Feldpausch
- 1] School of Geography, University of Leeds, Leeds LS2 9JT, UK. [2] Geography, College of Life and Environmental Sciences, University of Exeter, Rennes Drive, Exeter EX4 4RJ, UK
| | - E Gloor
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - T R Baker
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - J Lloyd
- 1] Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire SL5 7PY, UK. [2] School of Marine and Tropical Biology, James Cook University, Cairns, 4870 Queenland, Australia
| | | | - A Monteagudo-Mendoza
- Jardín Botánico de Missouri, Prolongacion Bolognesi Mz.e, Lote 6, Oxapampa, Pasco, Peru
| | - Y Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford OX1 3QK, UK
| | - S L Lewis
- 1] School of Geography, University of Leeds, Leeds LS2 9JT, UK. [2] Department of Geography, University College London, Pearson Building, Gower Street, London WC1E 6BT, UK
| | - R Vásquez Martinez
- Jardín Botánico de Missouri, Prolongacion Bolognesi Mz.e, Lote 6, Oxapampa, Pasco, Peru
| | - M Alexiades
- School of Anthropology and Conservation, Marlowe Building, University of Kent, Canterbury CT1 3EH, UK
| | - E Álvarez Dávila
- Servicios Ecosistemicos y Cambio Climático, Jardín Botánico de Medellín, Calle 73 no. 51 D-14, C.P. 050010, Medellín, Colombia
| | - P Alvarez-Loayza
- Center for Tropical Conservation, Duke University, Box 90381, Durham, North Carolina 27708, USA
| | - A Andrade
- Biological Dynamics of Forest Fragment Project (INPA &STRI), C.P. 478, Manaus AM 69011-970, Brazil
| | - L E O C Aragão
- 1] Geography, College of Life and Environmental Sciences, University of Exeter, Rennes Drive, Exeter EX4 4RJ, UK. [2] National Institute for Space Research (INPE), Av. Dos Astronautas, 1758, São José dos Campos, São Paulo 12227-010, Brazil
| | - A Araujo-Murakami
- Museo de Historia Natural Noel Kempff Mercado, Universidad Autonoma Gabriel Rene Moreno, Casilla 2489, Av. Irala 565, Santa Cruz, Bolivia
| | - E J M M Arets
- Alterra, Wageningen University and Research Centre, PO Box 47, 6700 AA Wageningen, The Netherlands
| | - L Arroyo
- Museo de Historia Natural Noel Kempff Mercado, Universidad Autonoma Gabriel Rene Moreno, Casilla 2489, Av. Irala 565, Santa Cruz, Bolivia
| | - G A Aymard C
- UNELLEZ-Guanare, Programa de Ciencias del Agro y el Mar, Herbario Universitario (PORT), Mesa de Cavacas, Estado Portuguesa, 3350 Venezuela
| | - O S Bánki
- Biodiversiteit en Ecosysteem Dynamica, University of Amsterdam, Postbus 94248, 1090 GE Amsterdam, The Netherlands
| | - C Baraloto
- 1] Institut National de la Recherche Agronomique, UMR EcoFoG, Campus Agronomique, 97310 Kourou, French Guiana. [2] International Center for Tropical Botany, Department of Biological Sciences, Florida International University, Miami, Florida 33199, USA
| | - J Barroso
- Universidade Federal do Acre, Campus de Cruzeiro do Sul, Rio Branco, Brazil
| | - D Bonal
- INRA, UMR 1137 ''Ecologie et Ecophysiologie Forestiere'' 54280 Champenoux, France
| | - R G A Boot
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - J L C Camargo
- Biological Dynamics of Forest Fragment Project (INPA &STRI), C.P. 478, Manaus AM 69011-970, Brazil
| | - C V Castilho
- Embrapa Roraima, Caixa Postal 133, Boa Vista, RR, CEP 69301-970, Brazil
| | - V Chama
- Universidad Nacional San Antonio Abad del Cusco, Av. de la Cultura N° 733, Cusco, Peru
| | - K J Chao
- 1] School of Geography, University of Leeds, Leeds LS2 9JT, UK. [2] International Master Program of Agriculture, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung 40227, Taiwan
| | - J Chave
- Université Paul Sabatier CNRS, UMR 5174 Evolution et Diversité Biologique, Bâtiment 4R1, 31062 Toulouse, France
| | - J A Comiskey
- Northeast Region Inventory and Monitoring Program, National Park Service, 120 Chatham Lane, Fredericksburg, Virginia 22405, USA
| | - F Cornejo Valverde
- Andes to Amazon Biodiversity Program, Puerto Maldonado, Madre de Dios, Peru
| | - L da Costa
- Universidade Federal do Para, Centro de Geociencias, Belem, CEP 66017-970 Para, Brazil
| | - E A de Oliveira
- Universidade do Estado de Mato Grosso, Campus de Nova Xavantina, Caixa Postal 08, CEP 78.690-000, Nova Xavantina MT, Brazil
| | - A Di Fiore
- Department of Anthropology, University of Texas at Austin, SAC Room 5.150, 2201 Speedway Stop C3200, Austin, Texas 78712, USA
| | - T L Erwin
- Department of Entomology, Smithsonian Institution, PO Box 37012, MRC 187, Washington DC 20013-7012, USA
| | - S Fauset
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - M Forsthofer
- Universidade do Estado de Mato Grosso, Campus de Nova Xavantina, Caixa Postal 08, CEP 78.690-000, Nova Xavantina MT, Brazil
| | - D R Galbraith
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - E S Grahame
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - N Groot
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - B Hérault
- Cirad, UMR Ecologie des Forêts de Guyane, Campus Agronomique, 97310 Kourou, French Guiana
| | - N Higuchi
- Biological Dynamics of Forest Fragment Project (INPA &STRI), C.P. 478, Manaus AM 69011-970, Brazil
| | - E N Honorio Coronado
- 1] School of Geography, University of Leeds, Leeds LS2 9JT, UK. [2] Instituto de Investigaciones de la Amazonía Peruana, Av. A. José Quiñones km 2.5, Iquitos, Peru
| | - H Keeling
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - T J Killeen
- World Wildlife Fund, 1250 24th Street NW, Washington DC 20037, USA
| | - W F Laurance
- Centre for Tropical Environmental and Sustainability Science (TESS) and School of Marine and Environmental Sciences, James Cook University, Cairns, Queensland 4878, Australia
| | - S Laurance
- Centre for Tropical Environmental and Sustainability Science (TESS) and School of Marine and Environmental Sciences, James Cook University, Cairns, Queensland 4878, Australia
| | - J Licona
- Instituto Boliviano de Investigación Forestal, C.P. 6201, Santa Cruz de la Sierra, Bolivia
| | - W E Magnussen
- National Institute for Research in Amazonia (INPA), C.P. 478, Manaus, Amazonas, CEP 69011-970, Brazil
| | - B S Marimon
- Universidade do Estado de Mato Grosso, Campus de Nova Xavantina, Caixa Postal 08, CEP 78.690-000, Nova Xavantina MT, Brazil
| | - B H Marimon-Junior
- Universidade do Estado de Mato Grosso, Campus de Nova Xavantina, Caixa Postal 08, CEP 78.690-000, Nova Xavantina MT, Brazil
| | - C Mendoza
- 1] FOMABO, Manejo Forestal en las Tierras Tropicales de Bolivia, Sacta, Bolivia. [2] Escuela de Ciencias Forestales (ESFOR), Universidad Mayor de San Simón (UMSS), Sacta, Bolivia
| | - D A Neill
- Universidad Estatal Amazónica, Facultad de Ingeniería Ambiental, Paso lateral km 2 1/2 via Napo, Puyo, Pastaza, Ecuador
| | - E M Nogueira
- National Institute for Research in Amazonia (INPA), C.P. 2223, 69080-971, Manaus, Amazonas, Brazil
| | - P Núñez
- Universidad Nacional San Antonio Abad del Cusco, Av. de la Cultura N° 733, Cusco, Peru
| | - N C Pallqui Camacho
- Universidad Nacional San Antonio Abad del Cusco, Av. de la Cultura N° 733, Cusco, Peru
| | - A Parada
- Museo de Historia Natural Noel Kempff Mercado, Universidad Autonoma Gabriel Rene Moreno, Casilla 2489, Av. Irala 565, Santa Cruz, Bolivia
| | - G Pardo-Molina
- Universidad Autonoma del Beni, Campus Universitario, Av. Ejército Nacional, Riberalta, Beni, Bolivia
| | - J Peacock
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - M Peña-Claros
- 1] Instituto Boliviano de Investigación Forestal, C.P. 6201, Santa Cruz de la Sierra, Bolivia. [2] Forest Ecology and Forest Management Group, Wageningen University, PO Box 47, 6700 AA Wageningen, The Netherlands
| | - G C Pickavance
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - N C A Pitman
- 1] Center for Tropical Conservation, Duke University, Box 90381, Durham, North Carolina 27708, USA. [2] The Field Museum, 1400 South Lake Shore Drive, Chicago, Illinois 60605-2496, USA
| | - L Poorter
- Forest Ecology and Forest Management Group, Wageningen University, PO Box 47, 6700 AA Wageningen, The Netherlands
| | - A Prieto
- Universidad Nacional de la Amazonía Peruana, Iquitos, Loreto, Peru
| | - C A Quesada
- National Institute for Research in Amazonia (INPA), C.P. 2223, 69080-971, Manaus, Amazonas, Brazil
| | - F Ramírez
- Universidad Nacional de la Amazonía Peruana, Iquitos, Loreto, Peru
| | - H Ramírez-Angulo
- Instituto de Investigaciones para el Desarrollo Forestal (INDEFOR), Universidad de Los Andes, Facultad de Ciencias Forestales y Ambientales, Conjunto Forestal, C.P. 5101, Mérida, Venezuela
| | - Z Restrepo
- Servicios Ecosistemicos y Cambio Climático, Jardín Botánico de Medellín, Calle 73 no. 51 D-14, C.P. 050010, Medellín, Colombia
| | - A Roopsind
- Iwokrama International Centre for Rainforest Conservation and Development, 77 High Street Kingston, Georgetown, Guyana
| | - A Rudas
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - R P Salomão
- Museu Paraense Emilio Goeldi, Av. Magalhães Barata, 376 - São Braz, CEP 66040-170, Belém PA, Brazil
| | - M Schwarz
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - N Silva
- UFRA, Av. Presidente Tancredo Neves 2501, CEP 66.077-901, Belém, Pará, Brazil
| | - J E Silva-Espejo
- Universidad Nacional San Antonio Abad del Cusco, Av. de la Cultura N° 733, Cusco, Peru
| | - M Silveira
- Museu Universitário, Universidade Federal do Acre, Rio Branco AC 69910-900, Brazil
| | - J Stropp
- European Commission - DG Joint Research Centre, Institute for Environment and Sustainability, Via Enrico Fermi 274, 21010 Ispra, Italy
| | - J Talbot
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
| | - H ter Steege
- 1] Naturalis Biodiversity Center, PO Box, 2300 RA, Leiden, The Netherlands. [2] Ecology and Biodiversity Group, Utrecht University, PO Box 80084, 3508 TB Utrecht, The Netherlands
| | - J Teran-Aguilar
- Museo de Historia Natural Alcide D'Orbigny, Av. Potosi no 1458, Cochabamba, Bolivia
| | - J Terborgh
- Center for Tropical Conservation, Duke University, Box 90381, Durham, North Carolina 27708, USA
| | - R Thomas-Caesar
- UFRA, Av. Presidente Tancredo Neves 2501, CEP 66.077-901, Belém, Pará, Brazil
| | - M Toledo
- Instituto Boliviano de Investigación Forestal, C.P. 6201, Santa Cruz de la Sierra, Bolivia
| | - M Torello-Raventos
- 1] School of Earth and Environmental Science, James Cook University, Cairns, Queensland 4870, Australia. [2] Centre for Tropical Environmental and Sustainability Science (TESS) and School of Marine and Tropical Biology, James Cook University, Cairns, Queensland 4878, Australia
| | - R K Umetsu
- Universidade do Estado de Mato Grosso, Campus de Nova Xavantina, Caixa Postal 08, CEP 78.690-000, Nova Xavantina MT, Brazil
| | - G M F van der Heijden
- 1] Northumbria University, School of Geography, Ellison Place, Newcastle upon Tyne, Newcastle NE1 8ST, UK. [2] University of Wisconsin, Milwaukee, Wisconsin 53202, USA. [3] Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panamá, Republic of Panama
| | - P van der Hout
- Van der Hout Forestry Consulting, Jan Trooststraat 6, 3078 HP Rotterdam, The Netherlands
| | - I C Guimarães Vieira
- Museu Paraense Emilio Goeldi, Av. Magalhães Barata, 376 - São Braz, CEP 66040-170, Belém PA, Brazil
| | - S A Vieira
- Universidade Estadual de Campinas, NEPAM, Rua dos Flamboyants, 155- Cidade Universitária Zeferino Vaz, Campinas, CEP 13083-867, Sao Paulo, Brazil
| | - E Vilanova
- Instituto de Investigaciones para el Desarrollo Forestal (INDEFOR), Universidad de Los Andes, Facultad de Ciencias Forestales y Ambientales, Conjunto Forestal, C.P. 5101, Mérida, Venezuela
| | - V A Vos
- 1] Universidad Autonoma del Beni, Campus Universitario, Av. Ejército Nacional, Riberalta, Beni, Bolivia. [2] Centro de Investigación y Promoción del Campesinado, regional Norte Amazónico, C/ Nicanor Gonzalo Salvatierra N° 362, Casilla 16, Riberalta, Bolivia
| | - R J Zagt
- Tropenbos International, PO Box 232, 6700 AE Wageningen, The Netherlands
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Barrs VR, Ujvari B, Dhand NK, Peters IR, Talbot J, Johnson LR, Billen F, Martin P, Beatty JA, Belov K. Detection of Aspergillus-specific antibodies by agar gel double immunodiffusion and IgG ELISA in feline upper respiratory tract aspergillosis. Vet J 2014; 203:285-9. [PMID: 25634077 DOI: 10.1016/j.tvjl.2014.12.020] [Citation(s) in RCA: 12] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 11/30/2014] [Accepted: 12/21/2014] [Indexed: 12/14/2022]
Abstract
Feline upper respiratory tract aspergillosis (URTA) is an emerging infectious disease. The aims of this study were: (1) to assess the diagnostic value of detection of Aspergillus-specific antibodies using an agar gel double immunodiffusion (AGID) assay and an indirect immunoglobulin G (IgG) ELISA; and (2) to determine if an aspergillin derived from mycelia of Aspergillus fumigatus, Aspergillus niger and Aspergillus flavus can be used to detect serum antibodies against cryptic Aspergillus spp. in Aspergillus section Fumigati. Sera from cats with URTA (group 1: n = 21) and two control groups (group 2: cats with other upper respiratory tract diseases, n = 25; group 3: healthy cats and cats with non-respiratory, non-fungal illness, n = 84) were tested. Isolates from cats with URTA comprised A. fumigatus (n = 5), A. flavus (n = 1) and four cryptic species: Aspergillus felis (n = 12), Aspergillus thermomutatus (Neosartorya pseudofischeri, n = 1), Aspergillus lentulus (n = 1) and Aspergillus udagawae (n = 1). Brachycephalic purebred cats were significantly more likely to develop URTA than other breeds (P = 0.013). The sensitivity (Se) of the AGID was 43% and the specificity (Sp) was 100%. At a cut-off value of 6 ELISA units/mL, the Se of the IgG ELISA was 95.2% and the Sp was 92% and 92.9% for groups 2 and 3 cats, respectively. Aspergillus-specific antibodies against all four cryptic species were detected in one or both assays. Assay Se was not associated with species identity. Detection of Aspergillus-specific antibodies by IgG ELISA has high Se and Sp for diagnosis of feline URTA.
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Affiliation(s)
- V R Barrs
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia.
| | - B Ujvari
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia
| | - N K Dhand
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia
| | - I R Peters
- TDDS, Innovation Centre, University of Exeter, Devon, UK
| | - J Talbot
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia
| | - L R Johnson
- School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - F Billen
- Faculty of Veterinary Medicine, University of Liege, Belgium
| | - P Martin
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia
| | - J A Beatty
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia
| | - K Belov
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia
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Treat CC, Wollheim WM, Varner RK, Grandy AS, Talbot J, Frolking S. Temperature and peat type control CO2 and CH4 production in Alaskan permafrost peats. Glob Chang Biol 2014; 20:2674-2686. [PMID: 24616169 DOI: 10.1111/gcb.12572] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [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: 11/12/2013] [Accepted: 02/28/2014] [Indexed: 06/03/2023]
Abstract
Controls on the fate of ~277 Pg of soil organic carbon (C) stored in permafrost peatland soils remain poorly understood despite the potential for a significant positive feedback to climate change. Our objective was to quantify the temperature, moisture, organic matter, and microbial controls on soil organic carbon (SOC) losses following permafrost thaw in peat soils across Alaska. We compared the carbon dioxide (CO2 ) and methane (CH4 ) emissions from peat samples collected at active layer and permafrost depths when incubated aerobically and anaerobically at -5, -0.5, +4, and +20 °C. Temperature had a strong, positive effect on C emissions; global warming potential (GWP) was >3× larger at 20 °C than at 4 °C. Anaerobic conditions significantly reduced CO2 emissions and GWP by 47% at 20 °C but did not have a significant effect at -0.5 °C. Net anaerobic CH4 production over 30 days was 7.1 ± 2.8 μg CH4 -C gC(-1) at 20 °C. Cumulative CO2 emissions were related to organic matter chemistry and best predicted by the relative abundance of polysaccharides and proteins (R(2) = 0.81) in SOC. Carbon emissions (CO2 -C + CH4 -C) from the active layer depth peat ranged from 77% larger to not significantly different than permafrost depths and varied depending on the peat type and peat decomposition stage rather than thermal state. Potential SOC losses with warming depend not only on the magnitude of temperature increase and hydrology but also organic matter quality, permafrost history, and vegetation dynamics, which will ultimately determine net radiative forcing due to permafrost thaw.
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Affiliation(s)
- C C Treat
- Earth Systems Research Center, Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH, USA
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de Freitas A, Donate PB, e Silva Castanheira FV, Borges V, Nascimento DC, Talbot J, Alves-Filho JC, Cunha F. Aryl hydrocarbon receptor activation increases survival in polymicrobial sepsis. Crit Care 2014. [PMCID: PMC4273856 DOI: 10.1186/cc14039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Gabrielli A, Talbot J, Viot P. Non-markovian models of blocking in concurrent and countercurrent flows. Phys Rev Lett 2013; 110:170601. [PMID: 23679696 DOI: 10.1103/physrevlett.110.170601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 02/20/2013] [Indexed: 06/02/2023]
Abstract
We investigate models in which blocking can interrupt a particulate flow process at any time. Filtration, and flow in micro or nanochannels and traffic flow are examples of such processes. We first consider concurrent flow models where particles enter a channel randomly. If at any time two particles are simultaneously present in the channel, failure occurs. The key quantities are the survival probability and the distribution of the number of particles that pass before failure. We then consider a counterflow model with two opposing Poisson streams. There is no restriction on the number of particles passing in the same direction, but blockage occurs if, at any time, two opposing particles are simultaneously present in the passage.
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Affiliation(s)
- A Gabrielli
- Istituto dei Sistemi Complessi (ISC)-CNR, UOS ‘‘Sapienza’’, Dipartimento di Fisica, University ‘‘Sapienza’’ di Roma,Piazzale Aldo Moro 5, 00185 Rome, Italy
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Abstract
Comparing slopes is a fundamental graph reading task and the aspect ratio chosen for a plot influences how easy these comparisons are to make. According to Banking to 45°, a classic design guideline first proposed and studied by Cleveland et al., aspect ratios that center slopes around 45° minimize errors in visual judgments of slope ratios. This paper revisits this earlier work. Through exploratory pilot studies that expand Cleveland et al.'s experimental design, we develop an empirical model of slope ratio estimation that fits more extreme slope ratio judgments and two common slope ratio estimation strategies. We then run two experiments to validate our model. In the first, we show that our model fits more generally than the one proposed by Cleveland et al. and we find that, in general, slope ratio errors are not minimized around 45°. In the second experiment, we explore a novel hypothesis raised by our model: that visible baselines can substantially mitigate errors made in slope judgments. We conclude with an application of our model to aspect ratio selection.
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Turetsky MR, Bond-Lamberty B, Euskirchen E, Talbot J, Frolking S, McGuire AD, Tuittila ES. The resilience and functional role of moss in boreal and arctic ecosystems. New Phytol 2012; 196:49-67. [PMID: 22924403 DOI: 10.1111/j.1469-8137.2012.04254.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Mosses in northern ecosystems are ubiquitous components of plant communities, and strongly influence nutrient, carbon and water cycling. We use literature review, synthesis and model simulations to explore the role of mosses in ecological stability and resilience. Moss community responses to disturbance showed all possible responses (increases, decreases, no change) within most disturbance categories. Simulations from two process-based models suggest that northern ecosystems would need to experience extreme perturbation before mosses were eliminated. But simulations with two other models suggest that loss of moss will reduce soil carbon accumulation primarily by influencing decomposition rates and soil nitrogen availability. It seems clear that mosses need to be incorporated into models as one or more plant functional types, but more empirical work is needed to determine how to best aggregate species. We highlight several issues that have not been adequately explored in moss communities, such as functional redundancy and singularity, relationships between response and effect traits, and parameter vs conceptual uncertainty in models. Mosses play an important role in several ecosystem processes that play out over centuries - permafrost formation and thaw, peat accumulation, development of microtopography - and there is a need for studies that increase our understanding of slow, long-term dynamical processes.
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Affiliation(s)
- M R Turetsky
- Department of Integrative Biology, University of Guelph, Guelph ON N1G 1G2, Canada
| | - B Bond-Lamberty
- Joint Global Change Research Institute, DOE Pacific Northwest National Laboratory, 5825 University Research Ct, College Park, MD, USA
| | - E Euskirchen
- University of Alaska Fairbanks, Institute of Arctic Biology, Fairbanks, AK 99775, USA
| | - J Talbot
- Institute for the Study of Earth, Oceans, and Space, and Department of Earth Sciences, University of New Hampshire, Durham, NH 03824, USA
- Département de Géographie, Université de Montréal, Montréal QC H2V 2B8, Canada
| | - S Frolking
- Institute for the Study of Earth, Oceans, and Space, and Department of Earth Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - A D McGuire
- US Geological Survey, Alaska Cooperative Fish and Wildlife Research Unit, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - E-S Tuittila
- School of Forest Sciences, University of Eastern Finland, PO Box 111, FIN-80101 Joensuu, Finland
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25
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Abstract
Within the framework of a Boltzmann-Lorentz equation, we analyze the dynamics of a granular rotor immersed in a bath of thermalized particles in the presence of a frictional torque on the axis. In numerical simulations of the equation, we observe two scaling regimes at low and high bath temperatures. In the large friction limit, we obtain the exact solution of a model corresponding to asymptotic behavior of the Boltzmann-Lorentz equation. In the limit of large rotor mass and small friction, we derive a Fokker-Planck equation for which the exact solution is also obtained.
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Affiliation(s)
- J Talbot
- Laboratoire de Physique Théorique de la Matière Condensée, UPMC, CNRS UMR, Paris, France
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26
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Talbot J, Evans V. Therapeutic hand massage: empowering carers to care. BMJ Support Palliat Care 2011. [DOI: 10.1136/bmjspcare-2011-000105.137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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27
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Lawley L, Talbot J, Franke D. Supporting end of life care delivery: an inclusive approach. BMJ Support Palliat Care 2011. [DOI: 10.1136/bmjspcare-2011-000105.135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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28
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Gratrix J, Fan S, Anderson B, Conroy P, Hewitt S, Parnell T, Jaipual J, Parker P, Singh AE, Talbot J. P5-S4.05 The use of financial compensation as an incentive for infectious syphilis case finding among vulnerable populations in Edmonton, Canada. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050108.546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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29
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MacDonald R, Debiais‐Thibaud M, Ma W, Yu M, Talbot J, Ekker M. [P1.37]: Function and regulation of
Dlx
homeobox genes during zebrafish GABAergic interneuron development. Int J Dev Neurosci 2010. [DOI: 10.1016/j.ijdevneu.2010.07.078] [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] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
| | | | - W. Ma
- University of OttawaCanada
| | - M. Yu
- University of OttawaCanada
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30
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Dewas S, Cochet A, Talbot J, Supiot S, Brunotte F, Rousseau C, Truc G, Bourdin S, Maingon P, Crehange G. Preliminary Results of Fluorocholine (18F) PET/CT (FCH PET/CT) for Guiding Salvage IG-IMRT in Patients with an Occult Recurrence from a Previously Treated Prostate Cancer. Int J Radiat Oncol Biol Phys 2010. [DOI: 10.1016/j.ijrobp.2010.07.794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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31
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Hayhurst C, Lebus C, Atkinson PR, Kendall R, Madan R, Talbot J, Ross P, Lewis D. An evaluation of echo in life support (ELS): is it feasible? What does it add? Emerg Med J 2010; 28:119-21. [DOI: 10.1136/emj.2009.084202] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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32
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Gelée B, Talbot J, Michel P, Larzul V, Boissière M. P501 - Convulsions de l’enfant : particularités et traitements des prises en charge en SMUR. Arch Pediatr 2010. [DOI: 10.1016/s0929-693x(10)70894-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Wilson P, Ellis J, MacEwen C, Ellingford A, Talbot J, Leese G. Screening for Diabetic Retinopathy: A Comparative Trial of Photography and Scanning Laser Ophthalmoscopy. Ophthalmologica 2010; 224:251-7. [DOI: 10.1159/000284351] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Accepted: 11/29/2009] [Indexed: 11/19/2022]
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34
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Reddy KA, Kumaran V, Talbot J. Orientational ordering in sheared inelastic dumbbells. Phys Rev E Stat Nonlin Soft Matter Phys 2009; 80:031304. [PMID: 19905107 DOI: 10.1103/physreve.80.031304] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Indexed: 05/28/2023]
Abstract
Using even driven simulations, we show that homogeneously sheared inelastic dumbbells in two dimensions are randomly orientated in the limit of low density. As the packing fraction is increased, particles first tend to orient along the extensional axis, and then as the packing fraction is further increased, the alignment shifts closer to the flow axis. The orientational order parameter displays a continuous increase with packing fraction and does not appear to exhibit a universal scaling with elongation. Except at the highest packing fractions, the orientational distribution function can be reconstructed with only the first coefficient of the Fourier expansion.
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Affiliation(s)
- K Anki Reddy
- Department of Chemical Engineering, Indian Institute of Science, Bangalore, 560012 India
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36
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Abstract
We examine the reversible adsorption of spherical solutes on a random site surface in which the adsorption sites are uniformly and randomly distributed on a substrate. Each site can be occupied by one solute provided that the nearest occupied site is at least one diameter away. The model is characterized by the site density and the bulk phase activity of the adsorbate. We develop a general statistical mechanical description of the model, and we obtain exact expressions for the adsorption isotherms in limiting cases of large and small activity and site density, particularly for the one-dimensional version of the model. We also propose approximate isotherms that interpolate between the exact results. These theories are in good agreement with numerical simulations of the model in two dimensions.
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Affiliation(s)
- J Talbot
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282-1530, USA
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37
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Douville P, Martel AR, Talbot J, Desmeules S, Langlois S, Agharazii M. Impact of age on glomerular filtration estimates. Nephrol Dial Transplant 2008; 24:97-103. [DOI: 10.1093/ndt/gfn473] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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38
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Honish L, Talbot J, Dragon D, Utgoff D. Outbreak of norovirus gastroenteritis at a university student residence--Edmonton, Alberta, 2006. Can Commun Dis Rep 2008; 34:1-7. [PMID: 18802982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- L Honish
- Capital Health-Public Health Division, Edmonton, Alberta, Canada
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39
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Talbot J, Tarjus G, Viot P. Exactly solvable model of reversible adsorption on a disordered substrate. Phys Rev E Stat Nonlin Soft Matter Phys 2007; 76:051106. [PMID: 18233622 DOI: 10.1103/physreve.76.051106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Indexed: 05/25/2023]
Abstract
We consider the reversible adsorption of particles (monomers with exclusion nearest-neighbor sites) on a one-dimensional lattice, where adsorption occurs on a finite fraction of sites selected randomly. By comparing this one-dimensional system to the pure system where all sites are available for adsorption, we show that when the activity goes to infinity, there exists a mapping between this model and the pure system at the same density. By examining the susceptibilities, we demonstrate that there is no mapping at finite activity. However, when the site density is small or moderate, the mapping exists up to second order in site density. We also propose and evaluate approximate approaches that may be applied to systems where no analytic result is known.
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Affiliation(s)
- J Talbot
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282-1530, USA
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41
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Piasecki J, Talbot J, Viot P. Angular velocity distribution of a granular planar rotator in a thermalized bath. Phys Rev E Stat Nonlin Soft Matter Phys 2007; 75:051307. [PMID: 17677054 DOI: 10.1103/physreve.75.051307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Indexed: 05/16/2023]
Abstract
The kinetics of a granular planar rotator with a fixed center undergoing inelastic collisions with bath particles is analyzed both numerically and analytically by means of the Boltzmann equation. The angular velocity distribution evolves from quasi-Gaussian in the Brownian limit to an algebraic decay in the limit of an infinitely light particle. In addition, we compare this model to that of a planar rotator with a free center and discuss the prospects for experimental confirmation of these results.
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Affiliation(s)
- J Piasecki
- Institute of Theoretical Physics, University of Warsaw, Hoza 69, Warsaw, Poland
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42
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Gratix J, Honish L, Mashinter L, Jaipaul J, Baptiste B, Doering D, Talbot J. Case series descriptive analysis of a primary syphilis outbreak in Edmonton, Alberta, July 2004-April 2006. Can Commun Dis Rep 2007; 33:61-7. [PMID: 17520772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Affiliation(s)
- J Gratix
- Public Health Division, Capital Health, Edmonton, Alberta
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43
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Barranger E, Kerrou K, Pitre S, Duval MA, Coutant C, Siebert R, Talbot J, Charon Y, Uzan S. First clinical results on the potential of intraoperative imaging for sentinel lymph node biopsy in breast cancer. Breast Cancer Res 2007. [DOI: 10.1186/bcr1728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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45
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46
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Affiliation(s)
- Ph. De Smedt
- a Department of Mathematics , Rutgers University , New Brunswick , New Jersey , 08903 , U.S.A
| | - J. Talbot
- a Department of Mathematics , Rutgers University , New Brunswick , New Jersey , 08903 , U.S.A
| | - J.L. Lebowitz
- a Department of Mathematics , Rutgers University , New Brunswick , New Jersey , 08903 , U.S.A
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47
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Affiliation(s)
- S Harding
- St. Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK.
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48
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Deniaud-Alexandre E, Touboul E, Lerouge D, Grahek D, Petegnief Y, Gres B, El Balaa H, Kerrou K, Milleron B, Lebeau B, Talbot J. Impact of Computed Tomography and 18F-Deoxyglucose-Hybrid Positron Emission Tomography Image Fusion on Conformal Radiotherapy in Non-Small Cell Lung Cancer. Int J Radiat Oncol Biol Phys 2005. [DOI: 10.1016/j.ijrobp.2005.07.175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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49
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Squirrell D, Dinakaran S, Dhingra S, Mody C, Brand C, Talbot J. Oral fluorescein angiography with the scanning laser ophthalmoscope in diabetic retinopathy: a case controlled comparison with intravenous fluorescein angiography. Eye (Lond) 2005; 19:411-7. [PMID: 15184968 DOI: 10.1038/sj.eye.6701513] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
AIM To compare the performance of oral fundus fluorescein angiography with a confocal scanning laser ophthalmoscope (SLO) with intravenous fundus fluorescein angiography (IVFFA) with a fundus camera in the assessment of sight-threatening diabetic retinopathy. PATIENTS AND METHODS A total of 25 patients undergoing IVFFA to investigate their diabetic retinopathy were recruited. Participants returned 1 week later and an oral angiogram with the SLO was performed. Six facets of the oral and intravenous angiograms were scored and compared: visualization of the foveal avascular zone (FAZ); branch retinal identification; macular leakage; identification of microaneurysms in areas of macular leakage; peripheral nonperfusion, and leakage from neovascular complexes. RESULTS Compared to IVFFA, the FAZ was unreliably visualized with oral angiography (Kappa 0.1, 95% CI 0-0.3). In contrast, macular leakage (Kappa 0.78, 95%, CI 0.72-0.83), identification of microaneurysms in areas of macular leakage (Kappa 0.78, 95%, CI 0.72-0.83), and neovascular complexes (Kappa 1.0) were reliably seen. Analysis of the visualization of peripheral nonperfusion was complicated by the finding that profuse dye leakage from neovascular complexes obscured the view of the peripheral retina. If the five angiograms in which this occurred were excluded, oral angiography identified 23 of the 24 eyes in which significant nonperfusion was found on IVFFA. CONCLUSION Oral angiography with the SLO can provide high-quality angiograms that allow judgments to be made about the presence of treatable diabetic maculopathy, proliferative diabetic retinopathy, and peripheral nonperfusion. In the presence of coexisting macular oedema, it proved to be an unreliable technique with which to investigate foveal ischaemia.
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Affiliation(s)
- D Squirrell
- Department of Ophthalmology, Royal Hallamshire Hospital, Sheffield, UK
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50
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Wildman RD, Martin TW, Krouskop PE, Talbot J, Huntley JM, Parker DJ. Convection in vibrated annular granular beds. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 71:061301. [PMID: 16089729 DOI: 10.1103/physreve.71.061301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2004] [Indexed: 05/03/2023]
Abstract
The response to vibration of a granular bed, consisting of a standard cylindrical geometry but with the addition of a dissipative cylindrical inner wall, has been investigated both experimentally (using positron emission particle tracking) and numerically (using hard sphere molecular dynamics simulation). The packing fraction profiles and granular temperature distributions (in both vertical and horizontal directions) were determined as a function of height and distance from the axis. The two sets of results were in reasonable agreement. The molecular dynamics simulations were used to explore the behavior of the granular bed in the inner wall-outer wall coefficient of restitution phase space. It was observed that one could control the direction of the toroidal convection rolls by manipulating the relative dissipation at the inner and outer walls via the coefficients of restitution, and with several layers of grains it was seen that double convection rolls could also be formed, a result that was subsequently confirmed experimentally.
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Affiliation(s)
- R D Wildman
- School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU, United Kingdom
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