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Oxide-free surfaces of polycrystalline Cu are prepared using acetic acid etching after chemical-mechanical polishing. UV ozone treatment is shown to increase the work function of the cleaned Cu by up to 0.5 eV. There is also a large reduction in quantum efficiency at 265 nm. Cu sheet can be easily masked from ozone exposure by Si or glass, meaning that selected-area oxi-dation is possible. Oxygen plasma treatment has a similar effect to the UV ozone but is more difficult to mask. There is no increase in surface roughness after oxidation, meaning that the larger work function could significantly re-duce dark current in accelerator photocathodes without affecting the desired photoemission region.
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X-ray micro-CT has been used to study the tracheal system of Pre and Post hibernation Queen wasps (Vespula vulgaris) and their workers. We have compared our findings in wasps with Snodgrass's description of the tracheal system of the honeybee as characterised by anatomical dissection. Our images, whilst broadly similar, identify the tracheal system as being considerably more complex than previously suggested. One of the 30 wasps imaged had a markedly different, previously undescribed tracheal system. Since completing this study, a large micro-CT study from the American Museum of Natural History (AMNH) has been published. This used different software (Slicer) and analysed 16bit digital data. We have compared our methods with that described in the AMNH publication, adopted their suggested nomenclature and have made recommendations for future studies.
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The Common Wasp, Vespula vulgaris (Hymenoptera: Vespidae), has an annual nest cycle with new colonies initiated by over-wintered queens. Survival of adult queen wasps through winter dormancy is enabled through the deposition of substantial quantities of triglycerides in fat bodies. Worker (and male) wasps lack these fat reserves. By comparing micro-CT scans of workers, pre-hibernation queens and post-hibernation queens, we demonstrate that it is possible to semi-quantitatively measure fat reserves using arbitrary X-ray attenuation ranges. Venom in the venom gland of the queen wasps, has a significantly lower X-ray attenuation value than the triglyceride-rich fat bodies. This may be due to its content of low molecular weight volatile pheromones in addition to its other known constituents. We also demonstrate the utility of micro-CT for visualising a range of physiological and anatomical features of insects. This non-destructive method for measuring fat reserves can be used on appropriately preserved or freshly collected insect specimens.
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Vespas , Masculino , Animais , Vespas/fisiologia , Raios X , Feromônios , Estações do Ano , TomografiaRESUMO
The objective of this paper is to determine whether deep tubewells installed through arsenic mitigation efforts in rural Bangladesh provide better drinking water microbial quality compared to shallow tubewells. We conducted a stratified random cross-sectional survey of 484 households to assess microbial contamination of deep tubewell water at source and at point of use (POU) compared to shallow tubewell water using the Compartment Bag Test. In addition, we measured storage time, distance, travel time and ownership status among both sets of users to assess deep tubewell efficacy and under what conditions they offer poorer or better water quality. Differences in tubewell characteristics were compared using non-parametric Mann-Whitney U tests and two-proportion Z-tests. Prevalence ratios of microbial contamination stratified by water quality, storage time and distance to tubewells and ownership were estimated using unadjusted Mantel-Haenszel tests. There was no significant difference in microbial contamination between shallow and deep tubewells at source. The presence of POU water microbial contamination in storage containers in deep tubewell households was 1.11 times the prevalence in shallow tubewell storage containers (95% CIâ¯=â¯0.97-1.27). Deep tubewell users stored water longer and walked significantly farther to obtain water compared to shallow tubewell users. Among deep tubewell households, those residing farther away from the source were 1.24 times as likely to drink contaminated water from storage containers compared to those located nearby (95% CIâ¯=â¯1.04-1.48). Our findings suggest that deep tubewells have comparable water quality to shallow tubewells at source, but increasing distance from the household exacerbates risk of microbial contamination at POU.
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Arsênio/análise , Monitoramento Ambiental , Microbiologia da Água , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Poços de Água , Bangladesh/epidemiologia , Estudos Transversais , Água Subterrânea , Humanos , População Rural , Poluição Química da Água/prevenção & controle , Qualidade da Água , Abastecimento de Água/estatística & dados numéricosRESUMO
Salmonella enterica serovar Wangata (S. Wangata) is an important cause of endemic salmonellosis in Australia, with human infections occurring from undefined sources. This investigation sought to examine possible environmental and zoonotic sources for human infections with S. Wangata in north-eastern New South Wales (NSW), Australia. The investigation adopted a One Health approach and was comprised of three complimentary components: a case-control study examining human risk factors; environmental and animal sampling; and genomic analysis of human, animal and environmental isolates. Forty-eight human S. Wangata cases were interviewed during a 6-month period from November 2016 to April 2017, together with 55 Salmonella Typhimurium (S. Typhimurium) controls and 130 neighbourhood controls. Indirect contact with bats/flying foxes (S. Typhimurium controls (adjusted odds ratio (aOR) 2.63, 95% confidence interval (CI) 1.06-6.48)) (neighbourhood controls (aOR 8.33, 95% CI 2.58-26.83)), wild frogs (aOR 3.65, 95% CI 1.32-10.07) and wild birds (aOR 6.93, 95% CI 2.29-21.00) were statistically associated with illness in multivariable analyses. S. Wangata was detected in dog faeces, wildlife scats and a compost specimen collected from the outdoor environments of cases' residences. In addition, S. Wangata was detected in the faeces of wild birds and sea turtles in the investigation area. Genomic analysis revealed that S. Wangata isolates were relatively clonal. Our findings suggest that S. Wangata is present in the environment and may have a reservoir in wildlife populations in north-eastern NSW. Further investigation is required to better understand the occurrence of Salmonella in wildlife groups and to identify possible transmission pathways for human infections.
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Saúde Única , Salmonelose Animal/epidemiologia , Salmonelose Animal/transmissão , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/transmissão , Salmonella/classificação , Salmonella/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Animais Domésticos/microbiologia , Animais Selvagens/microbiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Transmissão de Doença Infecciosa , Microbiologia Ambiental , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Fatores de Risco , Infecções por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Sorogrupo , Adulto JovemRESUMO
The anaesthesia practice in children observational trial of 31,127 patients in 261 European hospitals revealed a high (5.2%) incidence of severe critical events in the peri-operative period and wide variability in practice. A sub-analysis of the UK data was undertaken to investigate differences compared with the non-UK cohort in the incidence and nature of peri-operative severe critical events and to attempt to identify areas for quality improvement. In the UK cohort of 7040 paediatric patients from 43 hospitals, the overall incidence of peri-operative severe critical events was lower than in the non-UK cohort (3.3%, 95%CI: 2.9-3.8 vs. 5.8%, 95%CI: 5.5-6.1, RR 0.57, p < 0.001). There was a lower rate of bronchospasm (RR 0.22, 95%CI: 0.14-0.33; p < 0.001), stridor (RR 0.42, 95%CI: 0.28-0.65; p < 0.001) and cardiovascular instability (RR 0.69, 95%CI: 0.55-0.86; p = 0.001) than in the non-UK cohort. The proportion of sicker patients where less experienced teams were managing care was lower in the UK than in the non-UK cohort (10.4% vs. 20.4% of the ASA physical status 3 and 9% vs. 12.9% of the ASA physical status 4 patients). Differences in work-load between centres did not affect the incidence and outcomes of severe critical events when stratified for age and ASA physical status. The lower incidence of cardiovascular and respiratory complications could be partly attributed to more experienced dedicated paediatric anaesthesia providers managing the higher risk patients in the UK. Areas for quality improvement include: standardisation of serious critical event definitions; increased reporting; development of evidence-based protocols for management of serious critical events; development and rational use of paediatric peri-operative risk assessment scores; implementation of current best practice in provision of competent paediatric anaesthesia services in Europe; development of specific training in the management of severe peri-operative critical events; and implementation of systems for ensuring maintenance of skills.
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Anestesia , Assistência Perioperatória , Adolescente , Espasmo Brônquico/epidemiologia , Doenças Cardiovasculares/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Estudos Prospectivos , Melhoria de Qualidade , Sons Respiratórios , Reino UnidoRESUMO
Environments rarely remain the same over time, and populations are therefore frequently at risk of going extinct when changes are significant enough to reduce fitness. Although many studies have investigated what attributes of the new environments and of the populations experiencing these changes will affect their probability of going extinct, limited work has been directed towards determining the role of population history on the probability of going extinct during severe environmental change. Here, we compare the extinction risk of populations with a history of selection in a benign environment, to populations with a history of selection in one or two stressful environments. We exposed spores and lines of the green alga Chlamydomonas reinhardtii from these three different histories to a range of severe environmental changes. We found that the extinction risk was higher for populations with a history of selection in stressful environments compared to populations with a history of selection in a benign environment. This effect was not due to differences in initial population sizes. Finally, the rates of extinction were highly repeatable within histories, indicating strong historical contingency of extinction risk. Hence, information on the selection history of a population can be used to predict their probability of going extinct during environmental change.
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Chlamydomonas reinhardtii/fisiologia , Meio Ambiente , Extinção Biológica , Seleção Genética , Exposição Ambiental , Esporos/fisiologiaRESUMO
BACKGROUND: People with epilepsy have more concomitant medical conditions than the general population; these comorbidities play an important role in premature mortality. We sought to generate explanatory hypotheses about the co-occurrence of somatic comorbidities and epilepsy, avoiding causal and treatment-resultant biases. METHODS: We collected clinical, demographic and somatic comorbidity data for 2016 consecutive adults with epilepsy undergoing assessment at a tertiary centre and in 1278 people with epilepsy in the community. Underlying causes of epilepsy were not classed as comorbidities. RESULTS: Somatic comorbidities were more frequent in the referral centre (49%) where people more frequently had active epilepsy than in the community (36%). Consistent risk factors for comorbidities were found in both cohorts. Using multivariable ordinal regression adjusted for age, longer epilepsy duration and an underlying brain lesion were independently associated with a smaller burden of somatic conditions. The treatment burden, measured by the number of drugs to which people were exposed, was not an independent predictor. Shorter epilepsy duration was a predictor for conditions that conceivably harbour significant mortality risks. CONCLUSIONS: Somatic comorbidities do not occur randomly in relation to epilepsy; having more severe epilepsy seems to be a risk factor. Independently from age, the early period after epilepsy onset appears to be at particular risk, although it is not clear whether this relates to an early mortality or to a later decrease in the burden of comorbidities. These results suggest that, for some people, epilepsy should be considered a systemic condition not limited to the CNS.
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Epilepsia/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: The General Anesthesia compared to Spinal anesthesia (GAS) study is a prospective randomized, controlled, multisite, trial designed to assess the influence of general anesthesia (GA) on neurodevelopment at 5 years of age. A secondary aim obtained from the blood pressure data of the GAS trial is to compare rates of intraoperative hypotension after anesthesia and to identify risk factors for intraoperative hypotension. METHODS: A total of 722 infants ≤60 weeks postmenstrual age undergoing inguinal herniorrhaphy were randomized to either bupivacaine regional anesthesia (RA) or sevoflurane GA. Exclusion criteria included risk factors for adverse neurodevelopmental outcome and infants born at <26 weeks of gestation. Moderate hypotension was defined as mean arterial pressure measurement of <35 mm Hg. Any hypotension was defined as mean arterial pressure of <45 mm Hg. Epochs were defined as 5-minute measurement periods. The primary outcome was any measured hypotension <35 mm Hg from start of anesthesia to leaving the operating room. This analysis is reported primarily as intention to treat (ITT) and secondarily as per protocol. RESULTS: The relative risk of GA compared with RA predicting any measured hypotension of <35 mm Hg from the start of anesthesia to leaving the operating room was 2.8 (confidence interval [CI], 2.0-4.1; P < .001) by ITT analysis and 4.5 (CI, 2.7-7.4, P < .001) as per protocol analysis. In the GA group, 87% and 49%, and in the RA group, 41% and 16%, exhibited any or moderate hypotension by ITT, respectively. In multivariable modeling, group assignment (GA versus RA), weight at the time of surgery, and minimal intraoperative temperature were risk factors for hypotension. Interventions for hypotension occurred more commonly in the GA group compared with the RA group (relative risk, 2.8, 95% CI, 1.7-4.4 by ITT). CONCLUSIONS: RA reduces the incidence of hypotension and the chance of intervention to treat it compared with sevoflurane anesthesia in young infants undergoing inguinal hernia repair.
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Anestesia por Condução/efeitos adversos , Anestesia Geral/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Hipotensão/induzido quimicamente , Hipotensão/epidemiologia , Vigília/efeitos dos fármacos , Anestesia por Condução/tendências , Anestesia Geral/tendências , Pressão Sanguínea/fisiologia , Pré-Escolar , Humanos , Hipotensão/diagnóstico , Lactente , Recém-Nascido , Estudos Prospectivos , Vigília/fisiologiaRESUMO
The lateral ordering of arrays of self-assembled InAs-GaAs quantum dots (QDs) has been quantified as a function of growth rate, using the Hopkins-Skellam index (HSI). Coherent QD arrays have a spatial distribution which is neither random nor ordered, but intermediate. The lateral ordering improves as the growth rate is increased and can be explained by more spatially regular nucleation as the QD density increases. By contrast, large and irregular 3D islands are distributed randomly on the surface. This is consistent with a random selection of the mature QDs relaxing by dislocation nucleation at a later stage in the growth, independently of each QD's surroundings. In addition we explore the statistical variability of the HSI as a function of the number N of spatial points analysed, and we recommend N > 103 to reliably distinguish random from ordered arrays.
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OBJECTIVES: To assess the safety of intra-articular (IA) autologous tolerogenic dendritic cells (tolDC) in patients with inflammatory arthritis and an inflamed knee; to assess the feasibility and acceptability of the approach and to assess potential effects on local and systemic disease activities. METHODS: An unblinded, randomised, controlled, dose escalation Phase I trial. TolDC were differentiated from CD14+ monocytes and loaded with autologous synovial fluid as a source of autoantigens. Cohorts of three participants received 1×106, 3×106 or 10×106 tolDC arthroscopically following saline irrigation of an inflamed (target) knee. Control participants received saline irrigation only. Primary outcome was flare of disease in the target knee within 5â days of treatment. Feasibility was assessed by successful tolDC manufacture and acceptability via patient questionnaire. Potential effects on disease activity were assessed by arthroscopic synovitis score, disease activity score (DAS)28 and Health Assessment Questionnaire (HAQ). Immunomodulatory effects were sought in peripheral blood. RESULTS: There were no target knee flares within 5â days of treatment. At day 14, arthroscopic synovitis was present in all participants except for one who received 10×106 tolDC; a further participant in this cohort declined day 14 arthroscopy because symptoms had remitted; both remained stable throughout 91â days of observation. There were no trends in DAS28 or HAQ score or consistent immunomodulatory effects in peripheral blood. 9 of 10 manufactured products met quality control release criteria; acceptability of the protocol by participants was high. CONCLUSION: IA tolDC therapy appears safe, feasible and acceptable. Knee symptoms stabilised in two patients who received 10×106 tolDC but no systemic clinical or immunomodulatory effects were detectable. TRIAL REGISTRATION NUMBER: NCT01352858.
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Artrite Psoriásica/terapia , Artrite Reumatoide/terapia , Células Dendríticas/transplante , Adulto , Idoso , Artrite Psoriásica/imunologia , Artrite Reumatoide/imunologia , Artroscopia/métodos , Células Dendríticas/imunologia , Estudos de Viabilidade , Feminino , Humanos , Tolerância Imunológica , Articulação do Joelho , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Índice de Gravidade de Doença , Transplante Autólogo/efeitos adversos , Transplante Autólogo/métodos , Resultado do Tratamento , Adulto JovemRESUMO
The Universal Anaesthesia Machine has been developed as a complete anaesthesia workstation for use in low- and middle-income countries, where the provision of safe general anaesthesia is often compromised by unreliable supply of electricity and anaesthetic gases. We performed a functional and clinical assessment of this anaesthetic machine, with particular reference to novel features and functioning in the intended environment. The Universal Anaesthesia Machine was found to be reliable, safe and consistent across a range of tests during targeted functional testing.
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Anestesiologia/instrumentação , Adolescente , Anestesia Geral/instrumentação , Anestésicos Inalatórios/química , Criança , Pré-Escolar , Países em Desenvolvimento , Fontes de Energia Elétrica , Falha de Equipamento , Feminino , Saúde Global , Humanos , Lactente , Masculino , Oxigênio/administração & dosagem , Pobreza , Respiração ArtificialAssuntos
Citocromo P-450 CYP2D6/genética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Testes Genéticos/métodos , Ondansetron/farmacologia , Náusea e Vômito Pós-Operatórios/prevenção & controle , Tropizetrona/farmacologia , Antieméticos/farmacologia , Humanos , Farmacogenética/métodos , Polimorfismo Genético , Radioterapia/efeitos adversos , Agonistas do Receptor 5-HT3 de Serotonina/farmacologiaRESUMO
Doppler-free saturation spectroscopy provides a very powerful method to obtain detailed information about the electronic structure of the atom through measurement of the spectral line profile. This is achieved through a significant decrease in the Doppler broadening and essentially an elimination of the instrument broadening inherent to passive spectroscopic techniques. In this paper we present the technique and associated physics of Doppler-free saturation spectroscopy in addition to how one selects the appropriate transition. Simulations of Hδ spectra are presented to illustrate the increased sensitivity to both electric field and electron density measurements.
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A three-dimensional computer reconstruction of a plaice Pleuronectes platessa otolith is presented from data acquired by the Diamond Light synchrotron, beamline I12, X-ray source, a high energy (53-150 keV) source particularly well suited to the study of dense objects. The data allowed non-destructive rendering of otolith structure, and for the first time allows otolith annuli (internal ring structures) to be analysed in X-ray tomographic images.
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Peixes/crescimento & desenvolvimento , Membrana dos Otólitos/diagnóstico por imagem , Animais , Imageamento Tridimensional , Membrana dos Otólitos/crescimento & desenvolvimento , Síncrotrons , Tomografia , Tomografia Computadorizada por Raios X/métodosRESUMO
Pancreatic beta-cells play a pivotal role to synthesize and secrete insulin, as the solo source of the body. Physical as well as functional loss of beta-cells over a certain threshold result in diabetes. While the mechanisms underlying beta-cell loss in various types of diabetes have been extensively studied, less is known about residual beta-cells, found even in autoimmune type 1 diabetes and type 2 diabetes with a substantial amount. Why have these beta-cells been spared? Some patients with neonatal diabetes have demonstrated the life-changing restoration of functional beta-cells that were inactive for decades but awakened in several weeks following specific treatment. The recent striking outcomes of bariatric surgery in many obese diabetic patients indicate that their beta-cells are likely "preserved" rather than irreversibly lost even in the multifactorial polygenic state that is type 2 diabetes. Collectively, the preservation of residual beta-cells in various diabetic conditions challenges us regarding our understanding of beta-cell death and survival, where their sustenance may stem from the existence of resting beta-cells under physiological conditions. We posit that beta-cells rest and that studies of this normal feature of beta-cells could lead to new approaches for potentially reactivating and preserving beta-cell mass in order to treat diabetes.
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Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/patologia , Células Secretoras de Insulina/patologia , Células Secretoras de Insulina/fisiologia , Animais , Contagem de Células , Ciclo Celular , Citoproteção , Humanos , Insulina/metabolismo , Secreção de Insulina , Regeneração/fisiologiaRESUMO
This article provides nomenclature recommendations developed by an international workgroup to increase transparency and standardization of pharmacogenetic (PGx) result reporting. Presently, sequence variants identified by PGx tests are described using different nomenclature systems. In addition, PGx analysis may detect different sets of variants for each gene, which can affect interpretation of results. This practice has caused confusion and may thereby impede the adoption of clinical PGx testing. Standardization is critical to move PGx forward.
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Alelos , Testes Genéticos/normas , Farmacogenética/normas , Terminologia como Assunto , Genes , Testes Genéticos/tendências , Variação Genética , Humanos , Farmacogenética/tendências , Medicina de PrecisãoRESUMO
BACKGROUND: Resistance training (RT) improves muscular strength, physical functioning and quality of life in prostate cancer survivors, but the optimal frequency of RT is unknown. We conducted a pilot randomized controlled trial to compare the effects of 3 versus 2 days per week of RT in prostate cancer survivors diagnosed within the past 2 years. METHODS: Prostate cancer survivors (N=30) were randomized to 12 weeks of supervised RT performed either 3 days per week (n=16) or 2 days per week (n=14). The primary outcome was muscular strength assessed by a multiple repetition maximum test at baseline and postintervention. Secondary outcomes were objective physical functioning, quality of life and psychosocial functioning. RESULTS: A trend (P<0.10) and/or potentially meaningful effects (standardized effect size d⩾0.20) were found favoring 3 days per week over 2 days per week for the primary outcome of lower body strength (mean difference=27.8 kg; 95% confidence interval=-0.9 to 56.5; P=0.057; d=0.72) and for the secondary outcomes of 30-s chair stand (d=0.29; P=0.31), sit and reach (d=0.24; P=0.33), 6 -min walk (d=0.21; P=0.42) and the physical component summary (d=0.21; P=0.41). Conversely, a trend and/or potentially meaningful effects were found favoring 2 days per week over 3 days per week for the mental component summary (d=-0.38; P=0.10), mental health (d=-0.44; P=0.11), vitality (d=-0.31; P=0.28), role-emotional (d=-0.23; P=0.43), anxiety (d=0.32; P=0.29), happiness (d=-0.31; P=0.36) and perceived stress (d=0.23; P=0.39). CONCLUSIONS: This pilot randomized dose-comparison trial provides preliminary data to suggest that RT 3 days per week compared with 2 days per week may improve the strength and physical functioning in prostate cancer survivors, but may also blunt improvements in psychosocial functioning. Larger and more targeted phase II and III trials are needed to confirm the potentially complex effects of RT frequency in prostate cancer survivors.