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1.
BMJ Mil Health ; 169(1): 37-45, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35393357

RESUMO

BACKGROUND: This study evaluated cognitive workload in soldiers undertaking a long duration march wearing different loads. METHODS: Military participants (n=12 men and n=10 women) performed four 3-hour loaded marches (12.25 km at 4.9 km/hour) wearing either 21 kg, 26 kg, 33 kg or 43 kg. During the march, accuracy and response time were measured using the verbal working memory n-back test (0, 1, 2 and 3) and two bespoke Go/No Go tests (visual/auditory) to assess inhibition of a pre-potent response. RESULTS: The physical demands of the march increased with load and march duration but remained at moderate intensity. N-back test accuracy ranged from 74% to 98% in men and 62% to 98% in women. Reduced accuracy was observed as load and time increased. Accuracy during the visual Go/No Go test also reduced with load, accuracy ranged from 69% to 89% in men and 65% to 90% in women. No differences due to load or time were observed during completion of the auditory Go/No Go task; accuracy ranged from 93% to 97% in men and 77% to 95% in women. A number of participants were unable to complete the march due to discomfort. Reports of discomfort were more frequent in women, which may have contributed to the greater reductions in accuracy observed. CONCLUSION: These data provide further evidence that cognitive performance of military personnel can be affected during long duration loaded marching. Women reported discomfort from equipment more frequently than men, which may make them more susceptible to declines in cognitive performance. These findings highlight important considerations for equipment procurement.


Assuntos
Militares , Masculino , Humanos , Feminino , Militares/psicologia , Caminhada/fisiologia , Suporte de Carga/fisiologia , Fatores de Tempo , Cognição/fisiologia
2.
Earths Future ; 9(6): e2020EF001900, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34222555

RESUMO

Over the last decades, climate science has evolved rapidly across multiple expert domains. Our best tools to capture state-of-the-art knowledge in an internally self-consistent modeling framework are the increasingly complex fully coupled Earth System Models (ESMs). However, computational limitations and the structural rigidity of ESMs mean that the full range of uncertainties across multiple domains are difficult to capture with ESMs alone. The tools of choice are instead more computationally efficient reduced complexity models (RCMs), which are structurally flexible and can span the response dynamics across a range of domain-specific models and ESM experiments. Here we present Phase 2 of the Reduced Complexity Model Intercomparison Project (RCMIP Phase 2), the first comprehensive intercomparison of RCMs that are probabilistically calibrated with key benchmark ranges from specialized research communities. Unsurprisingly, but crucially, we find that models which have been constrained to reflect the key benchmarks better reflect the key benchmarks. Under the low-emissions SSP1-1.9 scenario, across the RCMs, median peak warming projections range from 1.3 to 1.7°C (relative to 1850-1900, using an observationally based historical warming estimate of 0.8°C between 1850-1900 and 1995-2014). Further developing methodologies to constrain these projection uncertainties seems paramount given the international community's goal to contain warming to below 1.5°C above preindustrial in the long-term. Our findings suggest that users of RCMs should carefully evaluate their RCM, specifically its skill against key benchmarks and consider the need to include projections benchmarks either from ESM results or other assessments to reduce divergence in future projections.

3.
Microb Genom ; 7(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34184982

RESUMO

The COVID-19 pandemic has spread rapidly throughout the world. In the UK, the initial peak was in April 2020; in the county of Norfolk (UK) and surrounding areas, which has a stable, low-density population, over 3200 cases were reported between March and August 2020. As part of the activities of the national COVID-19 Genomics Consortium (COG-UK) we undertook whole genome sequencing of the SARS-CoV-2 genomes present in positive clinical samples from the Norfolk region. These samples were collected by four major hospitals, multiple minor hospitals, care facilities and community organizations within Norfolk and surrounding areas. We combined clinical metadata with the sequencing data from regional SARS-CoV-2 genomes to understand the origins, genetic variation, transmission and expansion (spread) of the virus within the region and provide context nationally. Data were fed back into the national effort for pandemic management, whilst simultaneously being used to assist local outbreak analyses. Overall, 1565 positive samples (172 per 100 000 population) from 1376 cases were evaluated; for 140 cases between two and six samples were available providing longitudinal data. This represented 42.6 % of all positive samples identified by hospital testing in the region and encompassed those with clinical need, and health and care workers and their families. In total, 1035 cases had genome sequences of sufficient quality to provide phylogenetic lineages. These genomes belonged to 26 distinct global lineages, indicating that there were multiple separate introductions into the region. Furthermore, 100 genetically distinct UK lineages were detected demonstrating local evolution, at a rate of ~2 SNPs per month, and multiple co-occurring lineages as the pandemic progressed. Our analysis: identified a discrete sublineage associated with six care facilities; found no evidence of reinfection in longitudinal samples; ruled out a nosocomial outbreak; identified 16 lineages in key workers which were not in patients, indicating infection control measures were effective; and found the D614G spike protein mutation which is linked to increased transmissibility dominates the samples and rapidly confirmed relatedness of cases in an outbreak at a food processing facility. The large-scale genome sequencing of SARS-CoV-2-positive samples has provided valuable additional data for public health epidemiology in the Norfolk region, and will continue to help identify and untangle hidden transmission chains as the pandemic evolves.


Assuntos
COVID-19/patologia , Genoma Viral , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/virologia , Análise por Conglomerados , Surtos de Doenças , Ligação Genética , Humanos , Estudos Longitudinais , Pandemias , Filogenia , Polimorfismo de Nucleotídeo Único , SARS-CoV-2/classificação , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/genética , Reino Unido/epidemiologia , Sequenciamento Completo do Genoma
4.
BMJ Nutr Prev Health ; 4(2): 447-462, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35028515

RESUMO

BACKGROUND: Poor mental well-being is a major issue for young people and is likely to have long-term negative consequences. The contribution of nutrition is underexplored. We, therefore, investigated the association between dietary choices and mental well-being among schoolchildren. METHODS: Data from 7570 secondary school and 1253 primary school children in the Norfolk Children and Young People Health and Well-being Survey, open to all Norfolk schools during October 2017, were analysed. Multivariable linear regression was used to measure the association between nutritional factors and mental well-being assessed by the Warwick-Edinburgh Mental Well-being Scale for secondary school pupils, or the Stirling Children's Well-being Scale for primary school pupils. We adjusted all analyses for important covariates including demographic, health variables, living/home situation and adverse experience variables. RESULTS: In secondary school analyses, a strong association between nutritional variables and well-being scores was apparent. Higher combined fruit and vegetable consumption was significantly associated with higher well-being: well-being scores were 3.73 (95% CI 2.94 to 4.53) units higher in those consuming five or more fruits and vegetables (p<0.001; n=1905) compared with none (n=739). The type of breakfast or lunch consumed was also associated with significant differences in well-being score. Compared with children consuming a conventional type of breakfast (n=5288), those not eating any breakfast had mean well-being scores 2.73 (95% CI 2.11 to 3.35) units lower (p<0.001; n=1129) and those consuming only an energy drink had well-being scores 3.14 (95% CI 1.20 to 5.09) units lower (p=0.002; n=91). Likewise, children not eating any lunch had well-being scores 2.95 (95% CI 2.22 to 3.68) units lower (p<0.001; 860) than those consuming a packed lunch (n=3744). In primary school analyses, the type of breakfast or lunch was associated with significant differences in well-being scores in a similar way to those seen in secondary school data, although no significant association with fruit and vegetable intake was evident. CONCLUSION: These findings suggest that public health strategies to optimise the mental well-being of children should include promotion of good nutrition.

5.
J Cyst Fibros ; 19(1): 26-33, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31235360

RESUMO

There are many uncertainties regarding Cystic Fibrosis (CF) treatment. Recently, the first James Lind Alliance (JLA) Priority Setting Partnership (PSP) in CF was completed, bringing clinicians, patients and carers together to identify the Top 10 research priorities. Here we investigate how well the current clinical trials landscape reflects these priorities. Trials in CF were identified through searches of research databases (Pubmed, ANZCTR, EU clinical trials register, ClinicalTrials.gov and ISRCTN). Trials meeting inclusion criteria of registered intervention studies in CF published between 01.012016 and 11.09.2017 were matched to the Top 10 priorities. We identified 259 trials, with 193 fulfilling the inclusion criteria. Only 63 (33%) of these matched one or more of the JLA priorities showing that current clinical trials poorly reflect the JLA Top 10. By increasing awareness of the Top 10 priorities, it is hoped that this will fuel future research in areas important to the CF community.


Assuntos
Pesquisa Biomédica/métodos , Ensaios Clínicos como Assunto/normas , Fibrose Cística , Pesquisa , Fibrose Cística/genética , Fibrose Cística/terapia , Humanos , Avaliação das Necessidades
6.
J Cyst Fibros ; 19(4): e19-e24, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31740105

RESUMO

Airway clearance techniques (ACTs) are recommended in cystic fibrosis (CF) to prevent accumulation of secretions and lung infection. "Can exercise replace chest physiotherapy for people with CF?" is one of the CF community's top 10 research questions. We conducted an online survey of the CF community to gather data on current ACT use, recommendations, reported adherence levels and exercise strategies used. There were 488 respondents: 194 (40%) people with CF (pwCF), 141 (29%) family and 153 (31%) healthcare professionals (HCPs) (mostly physiotherapists). Only 10/285 (4%) of pwCF do no exercise at present and 163/303 (54%) already incorporate exercise into ACTs. ACTs were omitted by 128/267 (48%) of pwCF when they exercised. Nearly all (110/129, 93%) of HCPs currently recommend exercise to support ACTs. A trial replacing some or all ACTs with exercise, was supported by 80/110 (73%) of HCPs, with an additional 9/110 (8%) willing to consider in selected patients.


Assuntos
Manuseio das Vias Aéreas/métodos , Obstrução das Vias Respiratórias , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Exercícios Respiratórios , Fibrose Cística , Modalidades de Fisioterapia/estatística & dados numéricos , Adulto , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/prevenção & controle , Exercícios Respiratórios/métodos , Exercícios Respiratórios/estatística & dados numéricos , Fibrose Cística/complicações , Fibrose Cística/fisiopatologia , Fibrose Cística/terapia , Feminino , Humanos , Masculino , Depuração Mucociliar , Preferência do Paciente/estatística & dados numéricos , Terapia Respiratória/métodos , Inquéritos e Questionários
7.
BMC Health Serv Res ; 19(1): 711, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31638974

RESUMO

BACKGROUND: Despite people living with dementia representing a significant proportion of health and social care users, until recently in the United Kingdom (UK) there were no prescribed standards for dementia education and training. This audit sought to review the extent and nature of dementia education and training offered to health and social care staff in the UK against the standards described in the 2015 Dementia Training Standards Framework, which describes the knowledge and skills required of the UK dementia workforce. METHODS: This audit presents national data concerning the design, delivery, target audience, length, level, content, format of training, number of staff trained and frequency of delivery within existing dementia training programmes offered to health and social care staff. The Dementia Training Standards Framework was used as a reference for respondents to describe the subjects and learning outcomes associated with their training. RESULTS: The findings are presented from 614 respondents offering 386 training packages, which indicated variations in the extent and quality of training. Many training packages addressed the subjects of 'person-centred care', 'communication', 'interaction and behaviour in dementia care', and 'dementia awareness'. Few training packages addressed subjects concerning 'pharmacological interventions in dementia care', 'leadership' and 'end of life care'. Fewer than 40% of The Dementia Training Standards Framework learning outcomes targeted to staff with regular contact with people with dementia or in leadership roles were covered by the reported packages. However, for training targeted at increasing dementia awareness more than 70% of the learning outcomes identified in The Dementia Training Standards Framework were addressed. Many training packages are not of sufficient duration to derive impact; although the majority employed delivery methods likely to be effective. CONCLUSIONS: The development of new and existing training and education should take account of subjects that are currently underrepresented and ensure that training reflects the Training Standard Framework and evidence regarding best practice for delivery. Lessons regarding the limitations of training in the UK serve as a useful illustration of the challenge of implementing national dementia training standards; particularly for countries who are developing or have recently implemented national dementia strategies.


Assuntos
Demência , Pessoal de Saúde/educação , Capacitação em Serviço/organização & administração , Auditoria Médica , Benchmarking , Competência Clínica , Atenção à Saúde , Demência/terapia , Humanos , Reino Unido
8.
Res Involv Engagem ; 5: 24, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31452934

RESUMO

PLAIN ENGLISH SUMMARY: Cystic fibrosis (CF) is the commonest life-limiting inherited disorder in the UK. It affects many parts of the body including the lungs and gut leading to increased infection and problems digesting food. People with CF need to undergo many treatments each day throughout their whole lives. These include tablets, inhalers and breathing exercises, which are a huge burden, taking up several hours every dayIt is therefore, really important that the treatments we give are supported by good evidence, usually gathered from clinical trials. Unfortunately, we do not have good evidence for many of the CF treatments. We recently ran an exercise known as a James Lind Alliance Priority Setting Partnership (JLA PSP) to find out which the CF community feel are the top priority research questions. People with CF and those who look after them suggested questions to be answered by clinical trials. Through a series of online surveys and workshops these were then shortlisted to give a final top ten.Due to infection risk people with CF are advised not to mix, this meant we had to do things differently to the usual way JLA PSPs are carried out. We used videoconferencing to enable multiple people with CF to participate. Surveys were accessible online and promoted through social media. ABSTRACT: Background The James Lind Alliance (JLA) method is well recognised for setting research priorities. The JLA approach involves a combination of surveys and workshop interactions between patients, carers and health care professionals to identify and agree on a "top ten" list of research questions. Respiratory infection is one of the hallmarks of cystic fibrosis (CF). To avoid cross infection, patients are advised not to meet face to face, preventing us following standard JLA methodology. Here we describe adaptations made during our recent JLA Priority Setting Partnership (PSP) in CF. Methods We elicited and prioritised research questions, using sequential online surveys, promoted through social media. People with CF participated in steering committee meetings and the final workshop, using videoconferencing. Alterations to workshop methodology enabled participants attending in person and those joining remotely, to contribute equally. We also altered the JLA methodology to include "lone" questions, asked by only one survey respondent. We are now working with the CF community to co-produce research projects that answer these top ten. Results There were 482 respondents, from 23 countries, who submitted 1080 questions. Increases in the number of responses occurred just after promotion on social media. Use of videoconferencing enabled participation of multiple people with CF and ensured participation from anywhere in the world, including hospital inpatients. Inclusion of lone questions resulted in one being included in our top ten. Conclusions There is no "one-size-fits-all" for patient involvement methodologies. Through altering the JLA methods to fit our patient group we achieved wide participation. We believe that methods used in our project may also be applied to future partnerships to increase participation, especially where people may be hospitalised or be unable to travel. The methodology we are developing through the JLA PSP CF2 project may be useful for other PSPs to follow.

9.
Parkinsons Dis ; 2019: 5258493, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428303

RESUMO

OBJECTIVES: We piloted a computerised cognitive training battery in a group of participants with Parkinson's disease without dementia to investigate the relevance of the training to daily life and the feasibility and the acceptability of the tasks. Previous studies of CT have had limited success in the benefits of training, extending to improvements in everyday function. By taking a pragmatic approach and targeting training to the cognitive skills affected by Parkinson's disease (planning, attention, and recollection), whilst using tasks that emulated real-life scenarios, we sought to understand whether participants perceived the training to be effective and to identify the elements of the training that elicited beneficial effects. METHODS: Four participants completed a cognitive training session comprising three distinct tasks 5 days a week over two weeks. Participants completed baseline questionnaires examining health-related quality of life, everyday cognition, and apathy before the training period, after the last session, and two weeks after the last session. An interview was held after participants had completed the training. RESULTS: The findings indicated that participants felt the training was acceptable, enhanced their awareness, and encouraged them to monitor their thinking abilities. The group interview indicated that the training was feasible; participants felt the tasks had potential to improve everyday performance, but more supporting information should be provided to facilitate this transfer. Responses to the questionnaires reflected these findings, indicating improvement for some participants' cognition and quality of life. Objective measures supported the subjective reports; there were improvements in some but not all domains. Performance on the planning and recollection tasks improved over the training period, and the evidence for improvement on the attention task was mixed. CONCLUSION: This study has found that pragmatic computer-based training with real-life outcomes is both feasible and acceptable and should be evaluated more extensively using controlled methods.

10.
IEEE Trans Appl Supercond ; 29(5)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31360051

RESUMO

Readout of a large, spacecraft-based array of superconducting transition-edge sensors (TESs) requires careful management of the layout area and power dissipation of the cryogenic-circuit components. We present three optimizations of our time- (TDM) and code-division-multiplexing (CDM) systems for the X-ray Integral Field Unit (X-IFU), a several-thousand-pixel-TES array for the planned Athena-satellite mission. The first optimization is a new readout scheme that is a hybrid of CDM and TDM. This C/TDM architecture balances CDM's noise advantage with TDM's layout compactness. The second is a redesign of a component: the shunt resistor that provides a dc-voltage bias to the TESs. A new layout and a thicker Pd-Au resistive layer combine to reduce this resistor's area by more than a factor of 5. Third, we have studied the power dissipated by the first-stage SQUIDs (superconducting quantum-interference devices) and the readout noise versus the critical current of the first-stage SqUIDs. As a result, the X-IFU TDM and C/TDM SQUIDs will have a specified junction critical current of 5 µA. Based on these design optimizations and TDM experiments described by Durkin, et al. (these proceedings), TDM meets all requirements to be X-IFU's backup-readout option. Hybrid C/TDM is another viable option that could save spacecraft resources.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31186605

RESUMO

With the improving energy resolution of transitionedge sensor (TES) based microcalorimeters, performance verification and calibration of these detectors has become increasingly challenging, especially in the energy range below 1 keV where fluorescent atomic X-ray lines have linewidths that are wider than the detector energy resolution and require impractically high statistics to determine the gain and deconvolve the instrumental profile. Better behaved calibration sources such as grating monochromators are too cumbersome for space missions and are difficult to use in the lab. As an alternative, we are exploring the use of pulses of 3 eV optical photons delivered by an optical fiber to generate combs of known energies with known arrival times. Here, we discuss initial results of this technique obtained with 2 eV and 0.7 eV resolution X-ray microcalorimeters. With the 2 eV detector, we have achieved photon number resolution for pulses with mean photon number up to 133 (corresponding to 0.4 keV).

12.
Artigo em Inglês | MEDLINE | ID: mdl-31160861

RESUMO

Time-division multiplexing (TDM) is the backup readout technology for the X-ray Integral Field Unit (X-IFU), a 3,168-pixel X-ray transition-edge sensor (TES) array that will provide imaging spectroscopy for ESA's Athena satellite mission. X-0IFU design studies are considering readout with a multiplexing factor of up to 40. We present data showing 40-row TDM readout (32 TES rows + 8 repeats of the last row) of TESs that are of the same type as those being planned for X-IFU, using measurement and analysis parameters within the ranges specified for X-IFU. Singlecolumn TDM measurements have best-fit energy resolution of (1.91 ± 0.01) eV for the Al Kα complex (1.5 keV), (2.10 ± 0.02) eV for Ti Kα (4.5 keV), (2.23 ± 0.02) eV for Mn Kα (5.9 keV), (2.40 ± 0.02) eV for Co Kα (6.9 keV), and (3.44 ± 0.04) eV for Br Kα (11.9 keV). Three-column measurements have best-fit resolution of (2.03 ± 0.01) eV for Ti Kα and (2.40 ± 0.01) eV for Co Kα. The degradation due to the multiplexed readout ranges from 0.1 eV at the lower end of the energy range to 0.5 eV at the higher end. The demonstrated performance meets X-IFU's energy-resolution and energy-range requirements. True 40-row TDM readout, without repeated rows, of kilopixel scale arrays of X-IFU-like TESs is now under development.

13.
J Microbiol Methods ; 160: 73-83, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30926316

RESUMO

Absolute bacterial quantification receives little serious attention in the literature compared to sequencing, conceivably because it is considered unimportant and facile, or because existing methods are tedious, laborious and/or biased in nature. This is particularly true in engineered systems, including activated sludge, where such information underpins their design and operation. To overcome these limitations we built upon existing work and optimised and comprehensively validated, through comparison with epifluorescence microscopy (EFM), a rapid and precise flow cytometric protocol to enumerate total bacterial numbers in activated sludge. Insights into potential biases were evaluated using appropriate statistical analyses on this comparison, which spanned four orders of magnitude, as well as comparing volatile suspended solid (VSS) concentrations. The results suggest flow cytometry (FCM) is a rapid, reproducible and economical technique for quantifying total bacterial numbers and biomass concentrations in activated sludge, despite within order of magnitude discrepancies with EFM counts, which had inherent and evidently greater errors and biases than FCM. The use of FCM for routine monitoring over both EFM and VSS should help further understanding of the microbial ecology in, and the operation of, engineered systems.


Assuntos
Bactérias/isolamento & purificação , Microbiologia Ambiental , Esgotos/microbiologia , Purificação da Água/métodos
14.
Water Res ; 152: 264-273, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30682570

RESUMO

Viruses are thought to control bacterial abundance, affect community composition and influence ecosystem function in natural environments. Yet their dynamics have seldom been studied in engineered systems, or indeed in any system, for long periods of time. We measured virus abundance in a full-scale activated sludge plant every week for two years. Total bacteria and ammonia oxidising bacteria (AOB) abundances, bacterial community profiles, and a suite of environmental and operational parameters were also monitored. Mixed liquor virus abundance fluctuated over an order of magnitude (3.18 × 108-3.41 × 109 virus's mL-1) and that variation was statistically significantly associated with total bacterial and AOB abundance, community composition, and effluent concentrations of COD and NH4+- N and thus system function. This suggests viruses play a far more important role in the dynamics of activated sludge systems than previously realised and could be one of the key factors controlling bacterial abundance, community structure and functional stability and may cause reactors to fail. These findings are based on statistical associations, not mechanistic models. Nevertheless, viral associations with abiotic factors, such as pH, make physical sense, giving credence to these findings and highlighting the role that physical factors play in virus ecology. Further work is needed to identify and quantify specific bacteriophage and their hosts to enable us to develop mechanistic models of the ecology of viruses in wastewater treatment systems. However, since we have shown that viruses can be related to effluent quality and virus quantification is simple and cheap, practitioners would probably benefit from quantifying viruses now.


Assuntos
Ecossistema , Vírus , Amônia , Bactérias , Esgotos , Águas Residuárias
15.
J Low Temp Phys ; 193(5-6): 687-694, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31359888

RESUMO

The X-ray integral field unit (X-IFU) is a cryogenic spectrometer for the Advanced Telescope for High ENergy Astrophysics (ATHENA). ATHENA is a planned next-generation space-based X-ray observatory with capabilities that surpass the spectral resolution of prior missions. Proposed device designs contain up to 3840 transition edge sensors, each acting as an individual pixel on the detector, presenting a unique challenge for wiring superconducting leads in the focal plane assembly. In prototypes that require direct wiring, the edges of X-IFU focal plane have hosted aluminum wirebonding pads; however, indium (In) 'bumps' deposited on an interface layer such as molybdenum nitride (MoN) can instead be used as an array of superconducting interconnects. We investigated bumped MoN:In structures with different process cleans and layer thicknesses. Measurements of the resistive transitions showed variation of transition temperature T c as a function of bias and generally differed from the expected bulk T c of In (3.41 K). Observed resistance of the In bump structures at temperatures below the MoN transition (at 8.0 K) also depended on the varied parameters. For our proposed X-IFU geometry (10 µm of In mated to a 1-µm In bump), we measured a minimum T c of 3.14 K at a bias current of 3 mA and a normal resistance of 0.59 mΩ per interconnect. We also investigated the design and fabrication of superconducting niobium (Nb) microstrip atop flexible polyimide. We present a process for integrating In bumps with the flexible Nb leads to enable high-density wiring for the ATHENA X-IFU focal plane.

16.
J Low Temp Phys ; 193(3-4): 321-327, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31186584

RESUMO

We have specialized astronomical applications for X-ray microcalorimeters with superconducting transition edge sensors (TESs) that require exceptionally good TES performance, but which operate in the small-signal regime. We have therefore begun a program to carefully characterize the entire transition surface of TESs with and without the usual zebra stripes to see if there are reproducible local "sweet spots" where the performance is much better than average. These measurements require precise knowledge of the circuit parameters. Here, we show how the Shapiro effect can be used to precisely calibrate the value of the shunt-resistor. We are also investigating the effects of stress and external magnetic fields to better understand reproducibility problems.

17.
Artigo em Inglês | MEDLINE | ID: mdl-28804229

RESUMO

We are developing superconducting transition-edge sensor (TES) microcalorimeter focal planes for versatility in meeting specifications of X-ray imaging spectrometers including high count-rate, high energy resolution, and large field-of-view. In particular, a focal plane composed of two sub-arrays: one of fine-pitch, high count-rate devices and the other of slower, larger pixels with similar energy resolution, offers promise for the next generation of astrophysics instruments, such as the X-ray Integral Field Unit (X-IFU) instrument on the European Space Agency's Athena mission. We have based the sub-arrays of our current design on successful pixel designs that have been demonstrated separately. Pixels with an all gold X-ray absorber on 50 and 75 micron scales where the Mo/Au TES sits atop a thick metal heatsinking layer have shown high resolution and can accommodate high count-rates. The demonstrated larger pixels use a silicon nitride membrane for thermal isolation, thinner Au and an added bismuth layer in a 250 micron square absorber. To tune the parameters of each sub-array requires merging the fabrication processes of the two detector types. We present the fabrication process for dual production of different X-ray absorbers on the same substrate, thick Au on the small pixels and thinner Au with a Bi capping layer on the larger pixels to tune their heat capacities. The process requires multiple electroplating and etching steps, but the absorbers are defined in a single ion milling step. We demonstrate methods for integrating heatsinking of the two types of pixel into the same focal plane consistent with the requirements for each sub-array, including the limiting of thermal crosstalk. We also discuss fabrication process modifications for tuning the intrinsic transition temperature (Tc) of the bilayers for the different device types through variation of the bilayer thicknesses. The latest results on these "hybrid" arrays will be presented.

18.
Nature ; 544(7648): 84-87, 2017 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-28382993

RESUMO

Growth in terrestrial gross primary production (GPP)-the amount of carbon dioxide that is 'fixed' into organic material through the photosynthesis of land plants-may provide a negative feedback for climate change. It remains uncertain, however, to what extent biogeochemical processes can suppress global GPP growth. As a consequence, modelling estimates of terrestrial carbon storage, and of feedbacks between the carbon cycle and climate, remain poorly constrained. Here we present a global, measurement-based estimate of GPP growth during the twentieth century that is based on long-term atmospheric carbonyl sulfide (COS) records, derived from ice-core, firn and ambient air samples. We interpret these records using a model that simulates changes in COS concentration according to changes in its sources and sinks-including a large sink that is related to GPP. We find that the observation-based COS record is most consistent with simulations of climate and the carbon cycle that assume large GPP growth during the twentieth century (31% ± 5% growth; mean ± 95% confidence interval). Although this COS analysis does not directly constrain models of future GPP growth, it does provide a global-scale benchmark for historical carbon-cycle simulations.


Assuntos
Ciclo do Carbono , Dióxido de Carbono/metabolismo , Mudança Climática/história , Fotossíntese , Regiões Antárticas , Atmosfera/química , Dióxido de Carbono/análise , Sequestro de Carbono , Mudança Climática/estatística & dados numéricos , Retroalimentação , Mapeamento Geográfico , História do Século XX , Camada de Gelo/química , Modelos Teóricos , Folhas de Planta/metabolismo , Óxidos de Enxofre/análise
20.
Int J Nurs Stud ; 53: 144-51, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26421910

RESUMO

BACKGROUND: People with dementia occupy up to one quarter of acute hospital beds. However, the quality of care delivered to this patient group is of national concern. Staff working in acute hospitals report lack of knowledge, skills and confidence in caring for people with dementia. There is limited evidence about the most effective approaches to supporting acute hospital staff to deliver more person-centred care. OBJECTIVES: This study aimed to evaluate the efficacy of a specialist training programme for acute hospital staff regarding improving attitudes, satisfaction and feelings of caring efficacy, in provision of care to people with dementia. DESIGN: A repeated measures design, with measures completed immediately prior to commencing training (T1), after completion of Foundation level training (T2: 4-6 weeks post-baseline), and following Intermediate level training (T3: 3-4 months post-baseline). SETTING: One NHS Trust in the North of England, UK. PARTICIPANTS: 40 acute hospital staff working in clinical roles, the majority of whom (90%) were nurses. METHODS: All participants received the 3.5 day Person-centred Care Training for Acute Hospitals (PCTAH) programme, comprised of two levels, Foundation (0.5 day) and Intermediate (3 days), delivered over a 3-4 months period. Staff demographics and previous exposure to dementia training were collected via a questionnaire. Staff attitudes were measured using the Approaches to Dementia Questionnaire (ADQ), satisfaction in caring for people with dementia was captured using the Staff Experiences of Working with Demented Residents questionnaire (SEWDR) and perceived caring efficacy was measured using the Caring Efficacy Scale (CES). RESULTS: The training programme was effective in producing a significant positive change on all three outcome measures following intermediate training compared to baseline. A significant positive effect was found on the ADQ between baseline and after completion of Foundation level training, but not for either of the other measures. CONCLUSIONS: Training acute hospital staff in Intermediate level person-centred dementia care is effective in producing significant improvements in attitudes towards and satisfaction in caring for people with dementia and feelings of caring efficacy. Foundation level training is effective in changing attitudes but does not seem to be sufficient to bring about change in satisfaction or caring efficacy.


Assuntos
Demência/terapia , Recursos Humanos em Hospital/educação , Atitude do Pessoal de Saúde , Educação em Enfermagem , Humanos , Satisfação no Emprego , Psicoterapia Centrada na Pessoa , Recursos Humanos em Hospital/psicologia , Inquéritos e Questionários
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