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Lucas-Herald AK, Montezano AC, Alves-Lopes R, Haddow L, Alimussina M, O’Toole S, Flett M, Lee B, Amjad SB, Steven M, Brooksbank K, McCallum L, Delles C, Padmanabhan S, Ahmed SF, Touyz RM. Vascular dysfunction and increased cardiovascular risk in hypospadias. Eur Heart J 2022; 43:1832-1845. [PMID: 35567552 PMCID: PMC9113289 DOI: 10.1093/eurheartj/ehac112] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 12/30/2021] [Accepted: 02/15/2022] [Indexed: 11/30/2022] Open
Abstract
AIMS Hypogonadism is associated with cardiovascular disease. However, the cardiovascular impact of hypogonadism during development is unknown. Using hypospadias as a surrogate of hypogonadism, we investigated whether hypospadias is associated with vascular dysfunction and is a risk factor for cardiovascular disease. METHODS AND RESULTS Our human study spanned molecular mechanistic to epidemiological investigations. Clinical vascular phenotyping was performed in adolescents with hypospadias and controls. Small subcutaneous arteries from penile skin from boys undergoing hypospadias repair and controls were isolated and functional studies were assessed by myography. Vascular smooth muscle cells were used to assess: Rho kinase, reactive oxygen species (ROS), nitric oxide synthase/nitric oxide, and DNA damage. Systemic oxidative stress was assessed in plasma and urine. Hospital episode data compared men with a history of hypospadias vs. controls. In adolescents with hypospadias, systolic blood pressure (P = 0.005), pulse pressure (P = 0.03), and carotid intima-media thickness standard deviation scores (P = 0.01) were increased. Arteries from boys with hypospadias demonstrated increased U46619-induced vasoconstriction (P = 0.009) and reduced acetylcholine-induced endothelium-dependent (P < 0.0001) and sodium nitroprusside-induced endothelium-independent vasorelaxation (P < 0.0001). Men born with hypospadias were at increased risk of arrhythmia [odds ratio (OR) 2.8, 95% confidence interval (CI) 1.4-5.6, P = 0.003]; hypertension (OR 4.2, 95% CI 1.5-11.9, P = 0.04); and heart failure (OR 1.9, 95% CI 1.7-114.3, P = 0.02). CONCLUSION Hypospadias is associated with vascular dysfunction and predisposes to hypertension and cardiovascular disease in adulthood. Underlying mechanisms involve perturbed Rho kinase- and Nox5/ROS-dependent signalling. Our novel findings delineate molecular mechanisms of vascular injury in hypogonadism, and identify hypospadias as a cardiovascular risk factor in males.
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Campbell K, Gifford RJ, Singer J, Hill V, O’Toole A, Rambaut A, Hampson K, Brunker K. Making genomic surveillance deliver: A lineage classification and nomenclature system to inform rabies elimination. PLoS Pathog 2022; 18:e1010023. [PMID: 35500026 PMCID: PMC9162366 DOI: 10.1371/journal.ppat.1010023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 06/02/2022] [Accepted: 03/30/2022] [Indexed: 12/17/2022] Open
Abstract
The availability of pathogen sequence data and use of genomic surveillance is rapidly increasing. Genomic tools and classification systems need updating to reflect this. Here, rabies virus is used as an example to showcase the potential value of updated genomic tools to enhance surveillance to better understand epidemiological dynamics and improve disease control. Previous studies have described the evolutionary history of rabies virus, however the resulting taxonomy lacks the definition necessary to identify incursions, lineage turnover and transmission routes at high resolution. Here we propose a lineage classification system based on the dynamic nomenclature used for SARS-CoV-2, defining a lineage by phylogenetic methods for tracking virus spread and comparing sequences across geographic areas. We demonstrate this system through application to the globally distributed Cosmopolitan clade of rabies virus, defining 96 total lineages within the clade, beyond the 22 previously reported. We further show how integration of this tool with a new rabies virus sequence data resource (RABV-GLUE) enables rapid application, for example, highlighting lineage dynamics relevant to control and elimination programmes, such as identifying importations and their sources, as well as areas of persistence and routes of virus movement, including transboundary incursions. This system and the tools developed should be useful for coordinating and targeting control programmes and monitoring progress as countries work towards eliminating dog-mediated rabies, as well as having potential for broader application to the surveillance of other viruses.
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Sonnenberg P, Menezes D, Freeman L, Maxwell KJ, Reid D, Clifton S, Tanton C, Copas A, Riddell J, Dema E, Bosó Pérez R, Gibbs J, Ridge MC, Macdowall W, Unemo M, Bonell C, Johnson AM, Mercer CH, Mitchell K, Field N. Intimate physical contact between people from different households during the COVID-19 pandemic: a mixed-methods study from a large, quasi-representative survey (Natsal-COVID). BMJ Open 2022; 12:e055284. [PMID: 35140158 PMCID: PMC8829844 DOI: 10.1136/bmjopen-2021-055284] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 01/06/2022] [Indexed: 01/02/2023] Open
Abstract
OBJECTIVES Physical distancing as a non-pharmaceutical intervention aims to reduce interactions between people to prevent SARS-CoV-2 transmission. Intimate physical contact outside the household (IPCOH) may expand transmission networks by connecting households. We aimed to explore whether intimacy needs impacted adherence to physical distancing following lockdown in Britain in March 2020. METHODS The Natsal-COVID web-panel survey (July-August 2020) used quota-sampling and weighting to achieve a quasi-representative population sample. We estimate reporting of IPCOH with a romantic/sexual partner in the 4 weeks prior to interview, describe the type of contact, identify demographic and behavioural factors associated with IPCOH and present age-adjusted ORs (aORs). Qualitative interviews (n=18) were conducted to understand the context, reasons and decision making around IPCOH. RESULTS Of 6654 participants aged 18-59 years, 9.9% (95% CI 9.1% to 10.6%) reported IPCOH. IPCOH was highest in those aged 18-24 (17.7%), identifying as gay or lesbian (19.5%), and in steady non-cohabiting relationships (56.3%). IPCOH was associated with reporting risk behaviours (eg, condomless sex, higher alcohol consumption). IPCOH was less likely among those reporting bad/very bad health (aOR 0.54; 95% CI 0.32 to 0.93) but more likely among those with COVID-19 symptoms and/or diagnosis (aOR 1.34; 95% CI 1.10 to 1.65). Two-thirds (64.4%) of IPCOH was reported as being within a support bubble. Qualitative interviews found that people reporting IPCOH deliberated over, and made efforts to mitigate, the risks. CONCLUSIONS Given 90% of people did not report IPCOH, this contact may not be a large additional contributor to SARS-CoV-2 transmission, although heterogeneity exists within the population. Public health messages need to recognise how single people and partners living apart balance sexual intimacy and relationship needs with adherence to control measures.
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Pfeffer T, Keitel C, Kluger DS, Keitel A, Russmann A, Thut G, Donner TH, Gross J. Coupling of pupil- and neuronal population dynamics reveals diverse influences of arousal on cortical processing. eLife 2022; 11:e71890. [PMID: 35133276 PMCID: PMC8853659 DOI: 10.7554/elife.71890] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 02/04/2022] [Indexed: 11/13/2022] Open
Abstract
Fluctuations in arousal, controlled by subcortical neuromodulatory systems, continuously shape cortical state, with profound consequences for information processing. Yet, how arousal signals influence cortical population activity in detail has so far only been characterized for a few selected brain regions. Traditional accounts conceptualize arousal as a homogeneous modulator of neural population activity across the cerebral cortex. Recent insights, however, point to a higher specificity of arousal effects on different components of neural activity and across cortical regions. Here, we provide a comprehensive account of the relationships between fluctuations in arousal and neuronal population activity across the human brain. Exploiting the established link between pupil size and central arousal systems, we performed concurrent magnetoencephalographic (MEG) and pupillographic recordings in a large number of participants, pooled across three laboratories. We found a cascade of effects relative to the peak timing of spontaneous pupil dilations: Decreases in low-frequency (2-8 Hz) activity in temporal and lateral frontal cortex, followed by increased high-frequency (>64 Hz) activity in mid-frontal regions, followed by monotonic and inverted U relationships with intermediate frequency-range activity (8-32 Hz) in occipito-parietal regions. Pupil-linked arousal also coincided with widespread changes in the structure of the aperiodic component of cortical population activity, indicative of changes in the excitation-inhibition balance in underlying microcircuits. Our results provide a novel basis for studying the arousal modulation of cognitive computations in cortical circuits.
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Grocutt L, Paterson C, Valentine RM. Adaptive dose escalated radiotherapy in oropharyngeal cancers: a treatment planning feasibility study. Radiat Oncol 2022; 17:24. [PMID: 35123516 PMCID: PMC8817487 DOI: 10.1186/s13014-022-01991-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 01/17/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A significant proportion of patients with poor prognosis squamous cell cancer of the oropharynx relapse loco-regionally despite radical (chemo)radiotherapy. If a predictive biomarker for disease control can be identified during treatment then individualised and adaptive treatment strategies may be employed. The aim of this study is to assess the feasibility of adaptive and dose-escalated RT to the gross tumour volume without increasing surrounding planning target volume doses and maintaining clinically acceptable organs at risk doses. MATERIALS AND METHODS Twenty representative patients with poor prognosis locally advanced OPSCC who were known to have relapsed post RT, were re-planned retrospectively using Eclipse TPS v15.5, RapidPlan™ and multi-criteria optimisation. In our centre, PTV65 is treated with 65 Gy in 30 fractions while areas at risk of containing microscopic disease (PTV54) are treated synchronously to 54 Gy in 30 fractions. The original clinical plans were re-optimised to act as controls (Group I). These plans were split into two plans of 15 fractions each, with the latter 15 fractions used to escalate the dose to the GTV to 73 Gy (Group II) and 82 Gy (Group III). Plan sums were created for the total 30 fractions to record plan evaluation parameters along with assessments of plan deliverability. RESULTS For all groups, the dose coverage at D98% and D50% for the PTVs were comparable. The D2% dose levels for PTV65-GTV increased. All dose levels associated with PTV54 remained largely unaffected by the dose escalation regimens. Conformity indices for PTV65 and PTVAll (PTV65 plus PTV54) reveal comparable target volume coverage across all three groups. Despite the GTV being escalated by 12.3% and 26.2% in groups II and III, the volume of GTV receiving > 84 Gy was considerably less than 1.75 cc. While OAR doses increased for the escalated groups, these increases were not clinically significant. CONCLUSION This planning feasibility study exploring RapidPlan™ combined with multi-criteria optimisation has demonstrated that doses to the GTV may be escalated without increasing PTV65-GTV, PTV54 or OAR doses considerably, suggesting an interventional clinical trial using this approach would be feasible.
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Sambo M, Ferguson EA, Abela-Ridder B, Changalucha J, Cleaveland S, Lushasi K, Mchau GJ, Nanai A, Nonga H, Steenson R, Johnson PCD, Hampson K. Scaling-up the delivery of dog vaccination campaigns against rabies in Tanzania. PLoS Negl Trop Dis 2022; 16:e0010124. [PMID: 35143490 PMCID: PMC8865671 DOI: 10.1371/journal.pntd.0010124] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 02/23/2022] [Accepted: 12/27/2021] [Indexed: 11/18/2022] Open
Abstract
An increasing number of countries are committing to meet the global target to eliminate human deaths from dog-mediated rabies by 2030. Mass dog vaccination is central to this strategy. To interrupt rabies transmission from dogs to humans, the World Health Organization recommends that vaccination campaigns should be carried out every year in all dog-owning communities vaccinating 70% of their susceptible dogs. Monitoring and evaluation of dog vaccination campaigns are needed to measure progress towards elimination. In this study, we measured the delivery performance of large-scale vaccination campaigns implemented in 25 districts in south-east Tanzania from 2010 until 2017. We used regression modelling to infer the factors associated with, and potentially influencing the successful delivery of vaccination campaigns. During 2010–2017, five rounds of vaccination campaigns were carried out, vaccinating in total 349,513 dogs in 2,066 administrative vaccination units (rural villages or urban wards). Progressively more dogs were vaccinated over the successive campaigns. The campaigns did not reach all vaccination units each year, with only 16–28% of districts achieving 100% campaign completeness (where all units were vaccinated). During 2013–2017 when vaccination coverage was monitored, approximately 20% of vaccination units achieved the recommended 70% coverage, with average coverage around 50%. Campaigns were also not completed at annual intervals, with the longest interval between campaigns being 27 months. Our analysis revealed that districts with higher budgets generally achieved higher completeness, with a twofold difference in district budget increasing the odds of a vaccination unit being reached by a campaign by slightly more than twofold (OR: 2.29; 95% CI: 1.69–3.09). However, higher budgets did not necessarily result in higher coverage within vaccination units that were reached. We recommend national programs regularly monitor and evaluate the performance of their vaccination campaigns, so as to identify factors hindering their effective delivery and to guide remedial action. Globally there are approximately 59,000 annual human rabies deaths, with more than 99% of these resulting from dog-mediated rabies. Mass dog vaccination is known to be the cornerstone of effective control of dog rabies. Empirical and theoretical evidence shows that annual vaccination campaigns need to achieve 70% coverage of the susceptible dog population to interrupt transmission and ensure the dog population is protected until the next campaign. Recently, international organizations announced their commitment to reaching the global target of zero human deaths from dog-mediated rabies by 2030. Scaling-up of vaccinations is now underway in more than 100 rabies-endemic countries. However, there are operational and logistical challenges associated with scaling-up these operations in different geographical and cultural settings. This study monitored and evaluated the performance large-scale vaccinations in Tanzania. We found that vaccinations were not implemented in all villages, which resulted in coverage gaps. Additionally, vaccinations were not implemented annually and, as a result, coverage dropped below the critical vaccination threshold. We conclude that there is a need to improve the delivery of dog vaccinations for achieving the global target of zero dog-mediated human rabies deaths by 2030.
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McErlain H, Riley LM, Sutherland A. Palladium-Catalyzed C-P Bond-Forming Reactions of Aryl Nonaflates Accelerated by Iodide. J Org Chem 2021; 86:17036-17049. [PMID: 34726917 PMCID: PMC8650017 DOI: 10.1021/acs.joc.1c02172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Indexed: 11/28/2022]
Abstract
An iodide-accelerated, palladium-catalyzed C-P bond-forming reaction of aryl nonaflates is described. The protocol was optimized for the synthesis of aryl phosphine oxides and was found to be tolerant of a wide range of aryl nonaflates. The general nature of this transformation was established with coupling to other P(O)H compounds for the synthesis of aryl phosphonates and an aryl phosphinate. The straightforward synthesis of stable, isolable aryl nonaflates, in combination with the rapid C-P bond-forming reaction allows facile preparation of aryl phosphorus target compounds from readily available phenol starting materials. The synthetic utility of this general strategy was demonstrated with the efficient preparation of an organic light-emitting diode (OLED) material and a phosphonophenylalanine mimic.
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Seligsohn D, Crestani C, Gitahi N, Lejon Flodin E, Chenais E, Zadoks RN. Investigation of extramammary sources of Group B Streptococcus reveals its unusual ecology and epidemiology in camels. PLoS One 2021; 16:e0252973. [PMID: 34860840 PMCID: PMC8641886 DOI: 10.1371/journal.pone.0252973] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 11/18/2021] [Indexed: 11/19/2022] Open
Abstract
Camels are vital to food production in the drylands of the Horn of Africa, with milk as their main contribution to food security. A major constraint to camel milk production is mastitis, inflammation of the mammary gland. The condition negatively impacts milk yield and quality as well as household income. A leading cause of mastitis in dairy camels is Streptococcus agalactiae, or group B Streptococcus (GBS), which is also a commensal and pathogen of humans and cattle. It has been suggested that extramammary reservoirs for this pathogen may contribute to the occurrence of mastitis in camels. We explored the molecular epidemiology of GBS in camels using a cross-sectional study design for sample collection and phenotypic, genomic and phylogenetic analysis of isolates. Among 88 adult camels and 93 calves from six herds in Laikipia County, Kenya, GBS was detected in 20% of 50 milk samples, 25% of 152 nasal swabs, 8% of 90 oral swabs and 3% of 90 rectal swabs, but not in vaginal swabs. Per camel herd, two to four sequence types (ST) were identified using Multi Locus Sequence Typing (MLST). More than half of the isolates belonged to ST617 or its single-locus variant, ST1652, with these STs found across all sample types. Capsular serotype VI was detected in 30 of 58 isolates. In three herds, identical STs were detected in milk and swab samples, suggesting that extramammary sources of GBS may contribute to the maintenance and spread of GBS within camel herds. This needs to be considered when developing prevention and control strategies for GBS mastitis. The high nasal carriage rate, low recto-vaginal carriage rate, and high prevalence of serotype VI for GBS in camels are in stark contrast to the distribution of GBS in humans and in cattle and reveal hitherto unknown ecological and molecular features of this bacterial species.
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Bara D, Meekel EG, Pakamorė I, Wilson C, Ling S, Forgan RS. Exploring and expanding the Fe-terephthalate metal-organic framework phase space by coordination and oxidation modulation. MATERIALS HORIZONS 2021; 8:3377-3386. [PMID: 34665190 PMCID: PMC8628537 DOI: 10.1039/d1mh01663f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/12/2021] [Indexed: 05/19/2023]
Abstract
The synthesis of phase pure metal-organic frameworks (MOFs) - network solids of metal clusters connected by organic linkers - is often complicated by the possibility of forming multiple diverse phases from one metal-ligand combination. For example, there are at least six Fe-terephthalate MOFs reported to date, with many examples in the literature of erroneous assignment of phase based on diffraction data alone. Herein, we show that modulated self-assembly can be used to influence the kinetics of self-assembly of Fe-terephthalate MOFs. We comprehensively assess the effect of addition of both coordinating modulators and pH modulators on the outcome of syntheses, as well as probing the influence of the oxidation state of the Fe precursor (oxidation modulation) and the role of the counteranion on the phase(s) formed. In doing so, we shed light on the thermodynamic landscape of this phase system, uncover mechanistics of modulation, provide robust routes to phase pure materials, often as single crystals, and introduce two new Fe-terephthalate MOFs to an already complex system. The results highlight the potential of modulated self-assembly to bring precision control and new structural diversity to systems that have already received significant study.
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Dimogkioka AR, Lees J, Lacko E, Tokatlidis K. Protein import in mitochondria biogenesis: guided by targeting signals and sustained by dedicated chaperones. RSC Adv 2021; 11:32476-32493. [PMID: 35495482 PMCID: PMC9041937 DOI: 10.1039/d1ra04497d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/25/2021] [Indexed: 12/31/2022] Open
Abstract
Mitochondria have a central role in cellular metabolism; they are responsible for the biosynthesis of amino acids, lipids, iron-sulphur clusters and regulate apoptosis. About 99% of mitochondrial proteins are encoded by nuclear genes, so the biogenesis of mitochondria heavily depends on protein import pathways into the organelle. An intricate system of well-studied import machinery facilitates the import of mitochondrial proteins. In addition, folding of the newly synthesized proteins takes place in a busy environment. A system of folding helper proteins, molecular chaperones and co-chaperones, are present to maintain proper conformation and thus avoid protein aggregation and premature damage. The components of the import machinery are well characterised, but the targeting signals and how they are recognised and decoded remains in some cases unclear. Here we provide some detail on the types of targeting signals involved in the protein import process. Furthermore, we discuss the very elaborate chaperone systems of the intermembrane space that are needed to overcome the particular challenges for the folding process in this compartment. The mechanisms that sustain productive folding in the face of aggregation and damage in mitochondria are critical components of the stress response and play an important role in cell homeostasis.
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Killen SS, Christensen EAF, Cortese D, Závorka L, Norin T, Cotgrove L, Crespel A, Munson A, Nati JJH, Papatheodoulou M, McKenzie DJ. Guidelines for reporting methods to estimate metabolic rates by aquatic intermittent-flow respirometry. J Exp Biol 2021; 224:jeb242522. [PMID: 34520540 PMCID: PMC8467026 DOI: 10.1242/jeb.242522] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Interest in the measurement of metabolic rates is growing rapidly, because of the importance of metabolism in advancing our understanding of organismal physiology, behaviour, evolution and responses to environmental change. The study of metabolism in aquatic animals is undergoing an especially pronounced expansion, with more researchers utilising intermittent-flow respirometry as a research tool than ever before. Aquatic respirometry measures the rate of oxygen uptake as a proxy for metabolic rate, and the intermittent-flow technique has numerous strengths for use with aquatic animals, allowing metabolic rate to be repeatedly estimated on individual animals over several hours or days and during exposure to various conditions or stimuli. There are, however, no published guidelines for the reporting of methodological details when using this method. Here, we provide the first guidelines for reporting intermittent-flow respirometry methods, in the form of a checklist of criteria that we consider to be the minimum required for the interpretation, evaluation and replication of experiments using intermittent-flow respirometry. Furthermore, using a survey of the existing literature, we show that there has been incomplete and inconsistent reporting of methods for intermittent-flow respirometry over the past few decades. Use of the provided checklist of required criteria by researchers when publishing their work should increase consistency of the reporting of methods for studies that use intermittent-flow respirometry. With the steep increase in studies using intermittent-flow respirometry, now is the ideal time to standardise reporting of methods, so that - in the future - data can be properly assessed by other scientists and conservationists.
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Shimonovich M, Pearce A, Thomson H, Keyes K, Katikireddi SV. Assessing causality in epidemiology: revisiting Bradford Hill to incorporate developments in causal thinking. Eur J Epidemiol 2021; 36:873-887. [PMID: 33324996 PMCID: PMC8206235 DOI: 10.1007/s10654-020-00703-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 12/02/2020] [Indexed: 01/08/2023]
Abstract
The nine Bradford Hill (BH) viewpoints (sometimes referred to as criteria) are commonly used to assess causality within epidemiology. However, causal thinking has since developed, with three of the most prominent approaches implicitly or explicitly building on the potential outcomes framework: directed acyclic graphs (DAGs), sufficient-component cause models (SCC models, also referred to as 'causal pies') and the grading of recommendations, assessment, development and evaluation (GRADE) methodology. This paper explores how these approaches relate to BH's viewpoints and considers implications for improving causal assessment. We mapped the three approaches above against each BH viewpoint. We found overlap across the approaches and BH viewpoints, underscoring BH viewpoints' enduring importance. Mapping the approaches helped elucidate the theoretical underpinning of each viewpoint and articulate the conditions when the viewpoint would be relevant. Our comparisons identified commonality on four viewpoints: strength of association (including analysis of plausible confounding); temporality; plausibility (encoded by DAGs or SCC models to articulate mediation and interaction, respectively); and experiments (including implications of study design on exchangeability). Consistency may be more usefully operationalised by considering an effect size's transportability to a different population or unexplained inconsistency in effect sizes (statistical heterogeneity). Because specificity rarely occurs, falsification exposures or outcomes (i.e., negative controls) may be more useful. The presence of a dose-response relationship may be less than widely perceived as it can easily arise from confounding. We found limited utility for coherence and analogy. This study highlights a need for greater clarity on BH viewpoints to improve causal assessment.
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Panja S, Seddon A, Adams DJ. Controlling hydrogel properties by tuning non-covalent interactions in a charge complementary multicomponent system. Chem Sci 2021; 12:11197-11203. [PMID: 34522317 PMCID: PMC8386653 DOI: 10.1039/d1sc02854e] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/22/2021] [Indexed: 12/29/2022] Open
Abstract
Mixing small molecule gelators is a promising route to prepare useful and exciting materials that cannot be accessed from any of the individual components. Here, we describe pH-triggered hydrogelation by mixing of two non-gelling amphiphiles. The intermolecular interactions among the molecules can be tuned either by controlling the degree of ionization of the components or by a preparative pathway, which enables us to control material properties such as gel strength, gel stiffness, thermal stability, and an unusual shrinking/swelling behaviour.
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Szczęsny R, Hoang TKA, Dobrzańska L, Gregory DH. Solution/Ammonolysis Syntheses of Unsupported and Silica-Supported Copper(I) Nitride Nanostructures from Oxidic Precursors. Molecules 2021; 26:4926. [PMID: 34443514 PMCID: PMC8402165 DOI: 10.3390/molecules26164926] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/07/2021] [Accepted: 08/11/2021] [Indexed: 11/16/2022] Open
Abstract
Herein we describe an alternative strategy to achieve the preparation of nanoscale Cu3N. Copper(II) oxide/hydroxide nanopowder precursors were successfully fabricated by solution methods. Ammonolysis of the oxidic precursors can be achieved essentially pseudomorphically to produce either unsupported or supported nanoparticles of the nitride. Hence, Cu3N particles with diverse morphologies were synthesized from oxygen-containing precursors in two-step processes combining solvothermal and solid-gas ammonolysis stages. The single-phase hydroxochloride precursor, Cu2(OH)3Cl was prepared by solution-state synthesis from CuCl2·2H2O and urea, crystallising with the atacamite structure. Alternative precursors, CuO and Cu(OH)2, were obtained after subsequent treatment of Cu2(OH)3Cl with NaOH solution. Cu3N, in the form of micro- and nanorods, was the sole product formed from ammonolysis using either CuO or Cu(OH)2. Conversely, the ammonolysis of dicopper trihydroxide chloride resulted in two-phase mixtures of Cu3N and the monoamine, Cu(NH3)Cl under similar experimental conditions. Importantly, this pathway is applicable to afford composite materials by incorporating substrates or matrices that are resistant to ammoniation at relatively low temperatures (ca. 300 °C). We present preliminary evidence that Cu3N/SiO2 nanocomposites (up to ca. 5 wt.% Cu3N supported on SiO2) could be prepared from CuCl2·2H2O and urea starting materials following similar reaction steps. Evidence suggests that in this case Cu3N nanoparticles are confined within the porous SiO2 matrix.
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Giuri D, Marshall LJ, Dietrich B, McDowall D, Thomson L, Newton JY, Wilson C, Schweins R, Adams DJ. Exploiting and controlling gel-to-crystal transitions in multicomponent supramolecular gels. Chem Sci 2021; 12:9720-9725. [PMID: 34349943 PMCID: PMC8293982 DOI: 10.1039/d1sc02347k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/11/2021] [Indexed: 12/31/2022] Open
Abstract
Multicomponent supramolecular gels provide opportunities to form materials that are not accessible when using the single components alone. Different scenarios are possible when mixing multiple components, from complete co-assembly (mixing of the components within the self-assembled structures formed) to complete self-sorting such that each structure contains only one of the components. Most examples of multicomponent gels that currently exist form stable gels. Here, we show that this can be used to control the mechanical properties of the gels, but what is probably most exciting is that we show that we can use a magnetic field to control the shape of the crystals. The gelling component aligns in a magnetic field and so results in anisotropic crystals being formed.
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Nászai M, Bellec K, Yu Y, Román-Fernández A, Sandilands E, Johansson J, Campbell AD, Norman JC, Sansom OJ, Bryant DM, Cordero JB. RAL GTPases mediate EGFR-driven intestinal stem cell proliferation and tumourigenesis. eLife 2021; 10:e63807. [PMID: 34096503 PMCID: PMC8216719 DOI: 10.7554/elife.63807] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 06/03/2021] [Indexed: 02/07/2023] Open
Abstract
RAS-like (RAL) GTPases function in Wnt signalling-dependent intestinal stem cell proliferation and regeneration. Whether RAL proteins work as canonical RAS effectors in the intestine and the mechanisms of how they contribute to tumourigenesis remain unclear. Here, we show that RAL GTPases are necessary and sufficient to activate EGFR/MAPK signalling in the intestine, via induction of EGFR internalisation. Knocking down Drosophila RalA from intestinal stem and progenitor cells leads to increased levels of plasma membrane-associated EGFR and decreased MAPK pathway activation. Importantly, in addition to influencing stem cell proliferation during damage-induced intestinal regeneration, this role of RAL GTPases impacts on EGFR-dependent tumourigenic growth in the intestine and in human mammary epithelium. However, the effect of oncogenic RAS in the intestine is independent from RAL function. Altogether, our results reveal previously unrecognised cellular and molecular contexts where RAL GTPases become essential mediators of adult tissue homeostasis and malignant transformation.
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MESH Headings
- Animals
- Animals, Genetically Modified
- Breast Neoplasms/enzymology
- Breast Neoplasms/genetics
- Breast Neoplasms/pathology
- Cell Line, Tumor
- Cell Proliferation
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cell Transformation, Neoplastic/pathology
- Drosophila Proteins/genetics
- Drosophila Proteins/metabolism
- Drosophila melanogaster/enzymology
- Drosophila melanogaster/genetics
- Endocytosis
- ErbB Receptors/genetics
- ErbB Receptors/metabolism
- Female
- Humans
- Hyperplasia
- Intestinal Mucosa/metabolism
- Intestinal Mucosa/pathology
- Lung Neoplasms/enzymology
- Lung Neoplasms/genetics
- Lung Neoplasms/pathology
- Mammary Glands, Human/enzymology
- Mammary Glands, Human/pathology
- Mice, Inbred C57BL
- Mitogen-Activated Protein Kinases/metabolism
- Monomeric GTP-Binding Proteins/genetics
- Monomeric GTP-Binding Proteins/metabolism
- Receptors, Invertebrate Peptide/genetics
- Receptors, Invertebrate Peptide/metabolism
- Signal Transduction
- Stem Cells/metabolism
- Stem Cells/pathology
- ral GTP-Binding Proteins/genetics
- ral GTP-Binding Proteins/metabolism
- Mice
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67
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O'Boyle N, Roe AJ. Heterogeneity in populations of enterohaemorrhagic Escherichia coli undergoing D-serine adaptation. Curr Genet 2021; 67:221-224. [PMID: 33219834 PMCID: PMC8032621 DOI: 10.1007/s00294-020-01130-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 11/27/2022]
Abstract
Phenotypic and genetic heterogeneities are conserved features of prokaryotic populations. During periods of stress, this programmed diversity increases the likelihood that variants within the population will survive the adverse conditions, allowing for proliferation. Phenotypic heterogeneity can have a mutational or indeed a non-mutational basis as observed in bet-hedging strategies adopted by antibiotic-tolerant persister cells. Genetic variants can arise by phase variation (slip-strand mispairing, promoter inversions etc.), nucleotide polymorphisms resulting from replication errors or larger rearrangements such as deletions and insertions. In the face of selective pressures, these alterations may be neutral, beneficial or deleterious.We recently described the genetic basis of tolerance to a normally toxic metabolite, D-serine (D-ser) in enterohaemorrhagic E. coli (EHEC). Here we summarize our work in the context of population dynamics, provide further discussion on the distinction between these tolerance mechanisms and the importance of heterogeneity for maximising adaptive potential.
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68
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Paul A, Shipman MA, Onabule DY, Sproules S, Symes MD. Selective aldehyde reductions in neutral water catalysed by encapsulation in a supramolecular cage. Chem Sci 2021; 12:5082-5090. [PMID: 34163748 PMCID: PMC8179549 DOI: 10.1039/d1sc00896j] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 03/11/2021] [Indexed: 11/21/2022] Open
Abstract
The enhancement of reactivity inside supramolecular coordination cages has many analogies to the mode of action of enzymes, and continues to inspire the design of new catalysts for a range of reactions. However, despite being a near-ubiquitous class of reactions in organic chemistry, enhancement of the reduction of carbonyls to their corresponding alcohols remains very much underexplored in supramolecular coordination cages. Herein, we show that encapsulation of small aromatic aldehydes inside a supramolecular coordination cage allows the reduction of these aldehydes with the mild reducing agent sodium cyanoborohydride to proceed with high selectivity (ketones and esters are not reduced) and in good yields. In the absence of the cage, low pH conditions are essential for any appreciable conversion of the aldehydes to the alcohols. In contrast, the specific microenvironment inside the cage allows this reaction to proceed in bulk solution that is pH-neutral, or even basic. We propose that the cage acts to stabilise the protonated oxocarbenium ion reaction intermediates (enhancing aldehyde reactivity) whilst simultaneously favouring the encapsulation and reduction of smaller aldehydes (which fit more easily inside the cage). Such dual action (enhancement of reactivity and size-selectivity) is reminiscent of the mode of operation of natural enzymes and highlights the tremendous promise of cage architectures as selective catalysts.
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69
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Parry N, Wheadon H, Copland M. The application of BH3 mimetics in myeloid leukemias. Cell Death Dis 2021; 12:222. [PMID: 33637708 PMCID: PMC7908010 DOI: 10.1038/s41419-021-03500-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 01/31/2023]
Abstract
Execution of the intrinsic apoptotic pathway is controlled by the BCL-2 proteins at the level of the mitochondrial outer membrane (MOM). This family of proteins consists of prosurvival (e.g., BCL-2, MCL-1) and proapoptotic (e.g., BIM, BAD, HRK) members, the functional balance of which dictates the activation of BAX and BAK. Once activated, BAX/BAK form pores in the MOM, resulting in cytochrome c release from the mitochondrial intermembrane space, leading to apoptosome formation, caspase activation, and cleavage of intracellular targets. This pathway is induced by cellular stress including DNA damage, cytokine and growth factor withdrawal, and chemotherapy/drug treatment. A well-documented defense of leukemia cells is to shift the balance of the BCL-2 family in favor of the prosurvival proteins to protect against such intra- and extracellular stimuli. Small molecule inhibitors targeting the prosurvival proteins, named 'BH3 mimetics', have come to the fore in recent years to treat hematological malignancies, both as single agents and in combination with standard-of-care therapies. The most significant example of these is the BCL-2-specific inhibitor venetoclax, given in combination with standard-of-care therapies with great success in AML in clinical trials. As the number and variety of available BH3 mimetics increases, and investigations into applying these novel inhibitors to treat myeloid leukemias continue apace the need to evaluate where we currently stand in this rapidly expanding field is clear.
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70
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Carty DM, Harte R, Drummond RS, Ward R, Magid K, Collier D, Owens M, Korbonits M. AIP variant causing familial prolactinoma. Pituitary 2021; 24:48-52. [PMID: 33010004 PMCID: PMC7864850 DOI: 10.1007/s11102-020-01085-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/18/2020] [Indexed: 12/16/2022]
Abstract
Pathogenic variants in the aryl hydrocarbon receptor-interacting protein (AIP) gene are increasingly recognised as a cause of familial isolated pituitary adenoma. AIP-associated tumours are most commonly growth hormone (GH) producing. In our cohort of 175 AIP mutation positive patients representing 93 kindreds, 139 (79%) have GH excess, 19 have prolactinoma (17 familial and 2 sporadic cases) and out of the 17 clinically non-functioning tumours 4 were subsequently operated and found to be GH or GH & prolactin immunopositive adenoma. Here we report a family with an AIP variant, in which multiple family members are affected by prolactinoma, but none with GH excess. To our knowledge this is the first reported family with an AIP pathogenic variant to be affected solely by prolactinoma. These data suggest that prolactinoma families represent a small subset of AIP mutation positive kindreds, and similar to young-onset sporadic prolactinomas, AIP screening would be indicated.
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71
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Welsh TA, Draper ER. Water soluble organic electrochromic materials. RSC Adv 2021; 11:5245-5264. [PMID: 35424438 PMCID: PMC8694694 DOI: 10.1039/d0ra10346b] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 01/22/2021] [Indexed: 12/18/2022] Open
Abstract
Organic materials in electrochromic device applications possess a number of advantages over transition metal oxides like WO3 such as ease of synthesis and tunability, flexibility, and derivability from renewable feedstocks. However, these advantages are offset by the need to use organic solvents in their processing which are often flammable and/or toxic. Therefore, it is of paramount importance to the longterm economic and environmental sustainability of organic electronics research to develop water soluble organic materials. Herein, we describe the advances made in developing water soluble organic electronic materials for electrochromic applications. We here classify electrochromic materials into two broad categories: those that transition between colourless and coloured states (Type I) and those that transition between differently coloured states (Type II). The methods by which organic electrochromes are made water soluble are described in detail along with their potential applications in order to promote research in water soluble organic electronic materials in general.
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Faust CL, Brunker K, Ajambo D, Ryan M, Moses A, Rowel C, Wangoola RM, Wampande EM, Guma A, Adriko M, Lamberton PHL, Tukahebwa EM, Mugenyi A, Waiswa C. Harnessing technology and portability to conduct molecular epidemiology of endemic pathogens in resource-limited settings. Trans R Soc Trop Med Hyg 2021; 115:3-5. [PMID: 32945867 PMCID: PMC7788292 DOI: 10.1093/trstmh/traa086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 08/10/2020] [Accepted: 08/21/2020] [Indexed: 11/12/2022] Open
Abstract
Improvements in genetic and genomic technology have enabled field-deployable molecular laboratories and these have been deployed in a variety of epidemics that capture headlines. In this editorial, we highlight the importance of building physical and personnel capacity in low and middle income countries to deploy these technologies to improve diagnostics, understand transmission dynamics and provide feedback to endemic communities on actionable timelines. We describe our experiences with molecular field research on schistosomiasis, trypanosomiasis and rabies and urge the wider tropical medicine community to embrace these methods and help build capacity to benefit communities affected by endemic infectious diseases.
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73
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Robles-Zurita JA, Briggs A, Rana D, Quayyum Z, Oldroyd KG, Zeymer U, Desch S, de Waha-Thiele S, Thiele H. Economic evaluation of culprit lesion only PCI vs. immediate multivessel PCI in acute myocardial infarction complicated by cardiogenic shock: the CULPRIT-SHOCK trial. THE EUROPEAN JOURNAL OF HEALTH ECONOMICS : HEPAC : HEALTH ECONOMICS IN PREVENTION AND CARE 2020; 21:1197-1209. [PMID: 33029668 PMCID: PMC7561561 DOI: 10.1007/s10198-020-01235-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 09/16/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND The CULPRIT-SHOCK trial compared two treatment strategies for patients with acute myocardial infarction and multivessel coronary artery disease complicated by cardiogenic shock: (a) culprit vessel only percutaneous coronary intervention (CO-PCI), with additional staged revascularisation if indicated, and (b) immediate multivessel PCI (MV-PCI). METHODS A German societal and national health service perspective was considered for three different analyses. The cost utility analysis (CUA) estimated costs and quality adjusted life years (QALYs) based on a pre-trial decision analytic model taking a lifelong time horizon. In addition, a within trial CUA estimated QALYs and costs for 1 year. Finally, the cost effectiveness analysis (CEA) used the composite primary outcome, mortality and renal failure at 30-day follow-up, and the within trial costs. Econometric and survival analysis on the trial data was used for the estimation of the model parameters. Subgroup analysis was performed following an economic protocol. RESULTS The lifelong CUA showed an incremental cost effectiveness ratio (ICER), CO-PCI vs. MV-PCI, of €7010 per QALY and a probability of CO-PCI being the most cost-effective strategy > 64% at a €30,000 threshold. The ICER for the within trial CUA was €14,600 and the incremental cost per case of death/renal failure avoided at 30-day follow-up was €9010. Cost-effectiveness improved with patient age and for those without diabetes. CONCLUSIONS The estimates of cost-effectiveness for CO-PCI vs. MV-PCI have been shown to change depending on the time horizon and type of economic evaluation performed. The results favoured a long-term horizon analysis for avoiding underestimation of QALY gains from the CO-PCI arm.
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74
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Moncrieff L. In the Air of the Natural History Museum: On Corporate Entanglement and Responsibility in Uncontained Times. LAW AND CRITIQUE 2020; 31:253-273. [PMID: 38624449 PMCID: PMC7575699 DOI: 10.1007/s10978-020-09280-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/21/2020] [Indexed: 04/17/2024]
Abstract
This paper discusses corporate entanglement, impactfulness and responsibility in the Anthropocene, amidst events and conditions that 'uncontain' time. It takes its direction of travel from artist Brian Jungen's 'Cetology' (2002), a whalebone sculpture made out of cut-up plastic garden chairs, which conjoins the times of earth and world history, as it hangs in the air of the art gallery, 'as if' exhibited in the natural history museum. The paper relates 'Cetology's' engagement with natural history, time, and commodification to matters of corporate entanglement and responsibility within company law and governance. Problems with understanding the comparable imprint of large and multinational companies on matters, places, and communities are identified, after the domination of corporate legal frameworks over nature and the stability and perfection of economic incentives at law. The reading of this (critical-legal) situation is developed through theory and engagement with materialist and critical thinkers, who unite in their concern with distributed human-nature relations and the 'concreteness' that attends collisions in time, ruin and affect. Walter Benjamin and Theodor Adorno's writings are central to this analysis, and strengthen the commentary on 'natural history' themes curated by Jungen. The paper contemplates how times' uncontainment might invoke a change in expectation and method for the company law field, assigning contingency to the corporation and provoking a new mode of reflection about corporate entanglement and responsibility at law.
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75
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Cappelluti MD, Hadzifejzovic E, Foord JS, Gregory DH. Flash microwave-assisted solvothermal (FMS) synthesis of photoactive anatase sub-microspheres with hierarchical porosity. RSC Adv 2020; 10:37233-37245. [PMID: 35521252 PMCID: PMC9057126 DOI: 10.1039/d0ra05796g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 09/28/2020] [Indexed: 01/16/2023] Open
Abstract
The synthesis of nanostructured sub-microspheres of TiO2 anatase with hierarchical nano- and mesoporosity was successfully achieved by using an innovative approach that applies the principles of acidic digestion to microwave (MW) solvothermal synthesis. This process, termed flash microwave-assisted solvothermal (FMS) synthesis, facilitates the formation of spherical particles without surfactants or templating agents, exploiting the rapid reaction kinetics engendered by MW heating. Unlike many other MW-assisted solvothermal methods, the application of constant MW power leads to a rapid increase of the autogenous pressure, inducing burst-nucleation of small primary crystallites and subsequent rapid agglomeration into secondary particles, with reaction times reduced to minute-timescales. The use of non-aqueous polar solvents such as ethanol is key to the production of regular spheres with a narrow size distribution, composed of nanocrystallites. Morphology, porosity, specific surface area, phase composition, crystallite size and optical properties of the particles can be controlled via a judicious selection of physical and chemical synthesis parameters, especially precursor choice and acid concentration. The complex structure of the particles leads to surface areas of up to ca. 500 m2 g-1 with intergranular mesoporosity. The as-synthesised FMS particles show increased adsorption under dark conditions and selective de-ethylation of rhodamine B under visible light compared to a commercial photocatalyst (Degussa P25). The photodegradation mechanism hinges on the capacity of the spheres to accept electrons from the photoexcited state of molecules at the particle surface, with the large sphere surface area maximising adsorption capacity and improving the efficiency of the photocatalytic processes. The singular characteristics and properties of the particles could pave the way for further applications in water purification and optoelectronic devices.
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