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1.
BMC Public Health ; 24(1): 657, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429629

RESUMO

BACKGROUND: Environmentally sustainable food initiatives accompanying nutrition education, such as the Food Education and Sustainability Training (FEAST) program, have gained traction in school settings. The aim of this trial was to conduct an impact and process evaluation of FEAST, to evaluate its effect on children's fruit and vegetable (F&V) intakes, and secondary outcomes: F&V variety consumed, nutrition knowledge, food preparation/cooking skills, self-efficacy and behaviours, food waste knowledge and behaviours, and food production knowledge. METHODS: FEAST was a 10-week curriculum-aligned program, designed to educate children about healthy eating, food waste, and sustainability, while teaching cooking skills. It was implemented by classroom teachers, face-to-face and online, during COVID-19 school closures, in Australia in 2021. A custom designed survey was used to collect baseline and post-intervention data from students. Generalised linear mixed models (GLMM) estimated group differences in pre-post changes for primary and secondary outcomes. Surveys were also administered to students and teachers to evaluate intervention implementation. RESULTS: Twenty schools participated and self-selected to be either intervention schools (n = 10) or wait-list control (WLC) schools (n = 10). A total of 977, 5th and 6th grade children participated in the trial with a mean age of 11.1 years (SD ± 0.7). The FEAST intervention, compared to WLC, did not result in significant increases in primary outcomes nor secondary outcomes. The process evaluation revealed FEAST was well-received by students and teachers, but COVID-19 school closures hindered implementation fidelity with a less intense program delivered under the constraints of pandemic lockdowns. CONCLUSIONS: This is the first cluster non-randomized controlled trial designed to independently evaluate FEAST in the primary-school setting. No evidence was found for improved F&V intakes in children, nor secondary outcomes. However, the positive process evaluation results suggest that further trials of the program are warranted. If implemented as originally designed (pre-pandemic), with increased duration and complemented by supporting school policies, such programs have the potential to improve children's daily F&V intakes, cooking skills and food waste behaviours. This would support the Australian curriculum and contribute to: health promotion within schools and sustainable schools initiatives, the national agenda to reduce food waste and sustainable development goals. AUSTRALIAN AND NEW ZEALAND CLINICAL TRIALS REGISTRY: [ACTRN12620001347954]- Registered prospectively on 14/12/2020.


Assuntos
COVID-19 , Eliminação de Resíduos , Criança , Humanos , Alimentos , Austrália , Instituições Acadêmicas , COVID-19/prevenção & controle
2.
Chemistry ; 29(16): e202203843, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36519633

RESUMO

The crystal structures of metal-organic frameworks (MOFs) are typically determined by the strong chemical bonds formed between the organic and inorganic building units. However, the latest generation of redox-active frameworks often rely on counterions in the pores to access specific charge states of the components. Here, we model the crystal structures of three layered MOFs based on the redox-active ligand 2,5-dihydroxybenzoquinone (dhbq): Ti2 (Cl2 dhbq)3 , V2 (Cl2 dhbq)3 and Fe2 (Cl2 dhbq)3 with implicit and explicit counterions. Our full-potential first-principles calculations indicate that while the reported hexagonal structure is readily obtained for Ti and V, the Fe framework is stabilised only by the presence of explicit counterions. For high counterion concentrations, we observe the formation of an electride-like pocket in the pore center. An outlook is provided on the implications of solvent and counterion control for engineering the structures and properties of porous solids.

3.
Childs Nerv Syst ; 39(4): 975-982, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36580118

RESUMO

PURPOSE: Intracranial arteriovenous-malformation (AVM) is a relatively rare condition in pediatrics, yet is a major cause of spontaneous intracranial hemorrhage with a risk of fatal hemorrhage reported to be between 4 and 29%. Little is known about vessel morphology and optimum treatment modalities including multimodality combination therapy and prognosis in children. METHODS: A retrospective review of all children presenting to our institution from 2006 to 2020 that had an AVM was undertaken. RESULTS: A total of 50 children were identified with median age of 11 (range 1-16) years. The mean follow-up was 7.6 years. Forty-one children presented as an emergency and of those, 40 had hemorrhage identified on initial brain imaging. The average nidus size was 25 mm, drainage was superficial in 51% of cases, and located in eloquent cortex in 56%. The supplemental Spetzler-Martin grading indicated 78% (39/50) were grade 4 and above (moderate to high risk). Primary treatment modalities included embolization in 50% (25) or SRS in 30% (15) and surgery in 20% (10).The AVM was obliterated on follow-up DSA in 66% children. Three children had post-treatment hemorrhage, two related to embolization and one the day following SRS, giving a re-bleed rate of 6%. The GOSE was available for 32 children at long term follow and 94% had a good outcome (GOSE 5-8). Two children died due to acute hemorrhage (4%). CONCLUSION: The majority of children with AVM present with hemorrhage. The rebleed rate during definitive treatment is low at 6% over the study period. The selective use of the 3 modalities of treatment has significantly reduced mortality and severe disability.


Assuntos
Malformações Arteriovenosas Intracranianas , Radiocirurgia , Humanos , Criança , Lactente , Pré-Escolar , Adolescente , Resultado do Tratamento , Radiocirurgia/métodos , Malformações Arteriovenosas Intracranianas/complicações , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/terapia , Prognóstico , Estudos Retrospectivos , Hemorragias Intracranianas/cirurgia , Seguimentos
4.
J Dairy Sci ; 105(7): 5822-5835, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35525610

RESUMO

Pasture-based dairy systems aim to maximize the proportion of grazed pasture in the cow's diet by having a compact calving season that coincides with the onset of the grass growing season. In Ireland, where pasture-based systems are dominant, a key performance indicator that reflects the degree of compact calving is referred to as 6-wk calving rate (6-wk CR). Although the industry target is 90%, the national average 6-wk CR in Ireland is currently 67%. The aim of this study was to use qualitative research to understand in depth farmers' experiences in implementing a high 6-wk CR. Ten case-study dairy farmers were interviewed using the biographical narrative interpretive method. We identified 5 broad and often interrelated themes evoked by farmers regarding 6-wk CR: the "good" farmer; support networks; free time and family time; simplicity of a structured system; and profitability and monetary gain. The findings of this study identify complexities and challenges at farm level when it comes to increasing 6-wk CR, such as increased workload and challenges associated with large numbers of male calves born during a condensed calving season. Benefits experienced by farmers as a result of increasing 6-wk CR included increased days in milk and consequently improved cash flow as well as increased grass utilization. Our findings are of interest to researchers and extension agents involved in programs concerned with reproductive management in pasture-based dairy systems.


Assuntos
Indústria de Laticínios , Fazendeiros , Animais , Bovinos , Indústria de Laticínios/métodos , Fazendas , Feminino , Humanos , Irlanda , Masculino , Leite , Poaceae
5.
BMC Public Health ; 21(1): 967, 2021 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022839

RESUMO

BACKGROUND: The promotion of healthy eating is a public health priority. Poor dietary behaviours, including low fruit and vegetable (F&V) consumption are of particular concern among children. Novel nutrition promotion strategies are needed to improve F&V consumption. Sustainability education could be used to support nutrition education within the school context. The purpose of this paper is to report the protocol for impact and process evaluation of the school-based Food Education and Sustainability Training (FEAST) program, designed to educate children about sustainability, food waste and nutrition, using hands-on cooking activities. METHODS: A pragmatic, parallel, cluster non-randomized controlled trial with pre- and post-measures, will be implemented among 20 primary schools (10 intervention vs 10 wait-list-control) within NSW, Australia, involving children in Grades 5-6. FEAST is a curriculum-aligned program, delivered as a 1.5-h lesson/week, for a 10-week unit of inquiry, incorporating theory and cooking. FEAST was developed using theoretical frameworks which included Social Cognitive Theory and the Precede-Proceed Planning model. Primary outcomes include children's self-reported F&V intakes (serves/day). Food literacy constructs such as: nutrition knowledge, food preparation and cooking skills, self-efficacy and behaviours, food waste knowledge and behaviours and food production knowledge, will be assessed as secondary outcomes. Process evaluation will assess program reach, adoption, implementation, maintenance, satisfaction and perceived benefits by teachers and students. An online survey (including quantitative and qualitative questions) was developed for administration at baseline (impact evaluation) and immediately post-intervention (impact and process evaluation). Intervention effects on quantitative study outcomes will be estimated with ​generalised linear mixed models, including random effects and will follow the intention-to-treat principles. Open-ended questions embedded within the surveys will be analysed qualitatively using content and thematic analyses. DISCUSSION: Results from this trial will provide valuable information on the value of adding environmental sustainability strategies to nutrition education in schools. Results will inform the design of future research and programs focused on primary-school children's nutrition, sustainability-related behaviours and experiential school-based interventions. TRIAL REGISTRATION: Trial registered 14th December 2020 with the Australian and New Zealand Clinical Trials Registry ( ACTRN12620001347954 ).


Assuntos
Eliminação de Resíduos , Serviços de Saúde Escolar , Austrália , Criança , Promoção da Saúde , Humanos , Nova Zelândia , Avaliação de Programas e Projetos de Saúde , Instituições Acadêmicas
6.
Childs Nerv Syst ; 37(4): 1237-1241, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33174154

RESUMO

PURPOSE: The recent VNS models (AspireSR® Model 106, SenTiva™ Model 1000 (VNS Therapy®, LivaNova)) include a new function of cardiac-based seizure detection (CBSD) automatic stimulation, known as 'AutoStim'. This algorithm uses tachycardia as a proxy to a seizure, and the battery delivers a closed-loop electrical current in addition to its programmed stimulation. This function leads to further seizure reduction in adults, but this advantage has not been reported in the paediatric population. This study aims to investigate whether battery change with AutoStim leads to further seizure reduction in children. METHODS: This observational study included the first 10 cases of VNS battery change from non-AutoStim to AutoStim function. During the battery change operation, the new VNS was switched on, with the same normal and magnet mode settings as the previous VNS. The AutoStim mode was activated at the same time. Data on seizure burden were collected at 3 time points: (1) before the first VNS insertion, (2) before battery replacement (post-1st VNS) and (3) 12 months post-battery change (post-AutoStim). The net effect of AutoStim, the only changed parameter, was evaluated by comparing the seizure burden prior to and 12 months following battery change in each child. RESULTS: The seizure reduction improved significantly from 60 to 83% following battery change with AutoStim. Categorising the outcome according the McHugh classification, children achieving class I and II outcome (≥ 50% seizure reduction) improved from 70 to 90%. CONCLUSION: This is the first study to demonstrate the additional efficacy of AutoStim in children treated with VNS.


Assuntos
Estimulação do Nervo Vago , Adulto , Criança , Coração , Humanos , Convulsões/diagnóstico , Convulsões/terapia , Resultado do Tratamento , Nervo Vago
7.
Ann Oncol ; 31(11): 1553-1560, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32801017

RESUMO

BACKGROUND: This multicentre, randomised, double-blinded, placebo-controlled, phase II/III trial aimed to evaluate an oral THC:CBD (tetrahydrocannabinol:cannabidiol) cannabis extract for prevention of refractory chemotherapy-induced nausea and vomiting (CINV). Here we report the phase II component results. PATIENTS AND METHODS: Eligible patients experienced CINV during moderate-to-high emetogenic intravenous chemotherapy despite guideline-consistent antiemetic prophylaxis. Study treatment consisted of one cycle of 1-4 self-titrated capsules of oral THC 2.5 mg/CBD 2.5 mg (TN-TC11M) three times daily, from days -1 to 5, and 1 cycle of matching placebo in a crossover design, then blinded patient preference for a third cycle. The primary end point was the proportion of participants with complete response during 0-120 h from chemotherapy. A total of 80 participants provided 80% power to detect a 20% absolute improvement with a two-sided P value of 0.1. RESULTS: A total of 81 participants were randomised; 72 completing two cycles were included in the efficacy analyses and 78 not withdrawing consent were included in safety analyses. Median age was 55 years (range 29-80 years); 78% were female. Complete response was improved with THC:CBD from 14% to 25% (relative risk 1.77, 90% confidence interval 1.12-2.79, P = 0.041), with similar effects on absence of emesis, use of rescue medications, absence of significant nausea, and summary scores for the Functional Living Index-Emesis (FLIE). Thirty-one percent experienced moderate or severe cannabinoid-related adverse events such as sedation, dizziness, or disorientation, but 83% of participants preferred cannabis to placebo. No serious adverse events were attributed to THC:CBD. CONCLUSION: The addition of oral THC:CBD to standard antiemetics was associated with less nausea and vomiting but additional side-effects. Most participants preferred THC:CBD to placebo. Based on these promising results, we plan to recruit an additional 170 participants to complete accrual for the definitive, phase III, parallel group analysis. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12616001036404; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370473&isReview=true.


Assuntos
Antieméticos , Antineoplásicos , Canabidiol , Cannabis , Náusea , Vômito , Adulto , Idoso , Idoso de 80 Anos ou mais , Antieméticos/uso terapêutico , Antineoplásicos/uso terapêutico , Austrália , Canabidiol/uso terapêutico , Estudos Cross-Over , Método Duplo-Cego , Dronabinol/uso terapêutico , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Vômito/induzido quimicamente , Vômito/tratamento farmacológico
8.
Anim Genet ; 51(5): 675-682, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32537769

RESUMO

With the availability of a new highly contiguous Bos taurus reference genome assembly (ARS-UCD1.2), it is the opportune time to upgrade the bovine gene set by seeking input from researchers. Furthermore, advances in graphical genome annotation tools now make it possible for researchers to leverage sequence data generated with the latest technologies to collaboratively curate genes. For many years the Bovine Genome Database (BGD) has provided tools such as the Apollo genome annotation editor to support manual bovine gene curation. The goal of this paper is to explain the reasoning behind the decisions made in the manual gene curation process while providing examples using the existing BGD tools. We will describe the sources of gene annotation evidence provided at the BGD, including RNA-seq and Iso-Seq data. We will also explain how to interpret various data visualizations when curating gene models, and will demonstrate the value of manual gene annotation. The process described here can be applied to manual gene curation for other species with similar tools. With a better understanding of manual gene annotation, researchers will be encouraged to edit gene models and contribute to the enhancement of livestock gene sets.


Assuntos
Bases de Dados Genéticas , Genoma , Anotação de Sequência Molecular , Sistemas On-Line , Animais , Bovinos/genética
9.
Childs Nerv Syst ; 36(5): 1049-1054, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31848723

RESUMO

PURPOSE: Discitis in the paediatric population poses diagnostic challenges due to non-specific presenting symptoms and difficulty with expressing pain in non-communicating children. Discitis remains a relatively rare condition in the paediatric population and previous reports are limited to small cohorts. In this article, we report our experience in management of discitis over a 10-year period and review the literature on this topic. METHODS: We retrospectively reviewed cases of paediatric discitis/spondylodiscitis over a 10-year period between 2008 and 2018 managed in our regional paediatric neurosurgery unit. Relevant demographic information, microbiological data, blood investigation profile, antibiotic treatment duration and clinical outcomes were interrogated from clinical notes and electronic databases and further analysed. RESULTS: Overall, 21 cases of paediatric discitis were identified from year 2008 to 2018 with a female to male ratio of 1.3:1. The mean age at presentation was 4.3 years (range 1 to 15 years). Overall, there were 19 cases of lumbosacral/lumbar, 1 thoracic and 1 cervical discitis. The mean duration of follow-up was 20 months (range 6 to 69 months). The most common presenting features were back pain and refusal to walk/sit or weight bear. Erythrocyte sedimentation rate (ESR) was found to be more sensitive than C-reactive protein (CRP) (sensitivity 78% versus 38%) in our cohort. Computer tomography (CT)-guided biopsy was performed in five cases and only one of these was positive (20%). All patients were treated with intravenous antibiotics with resolution of discitis. CONCLUSIONS: Presentation of discitis in children can be non-specific and requires high index of suspicion. CT-guided biopsy in our cohort revealed a low rate of positive cultures. Despite negative blood cultures and CT-guided biopsy results, empirical intravenous antibiotics were effective in treating discitis successfully. In our cohort, low yield of CT-guided biopsy does not support its use on each case and this may be reserved for cases resistant to antimicrobial therapy or concerns regarding other pathology mimicking infection. Better understanding and awareness of this condition and its pathophysiology can lead to timely imaging, diagnosis and treatment.


Assuntos
Discite , Adolescente , Antibacterianos/uso terapêutico , Biópsia , Criança , Pré-Escolar , Discite/diagnóstico , Discite/tratamento farmacológico , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
10.
Childs Nerv Syst ; 36(7): 1435-1443, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31900628

RESUMO

INTRODUCTION: Developmental venous anomalies (DVAs) are anomalies of venous drainage and considered a low-flow malformation. Studies evaluating natural history and risk factors for intracranial haemorrhage in the paediatric population are rare. We evaluate clinical and radiological features, risk factors and outcomes of paediatric DVAs. METHODS: A retrospective study was conducted over a 10-year period between 2004 and 2014. Medical records, imaging and prospective databases were reviewed. Three-hundred-and-three radiological studies in total were evaluated. RESULTS: Fifty-two children (20 boys and 32 girls [median age: 6 years] were identified with DVAs. Their age distribution was as follows: 1.9% neonates (< 1 month), 11.5% infants (1 month to 1 year), 30.8% 1-5 years, 30.8% 5-12 years and 25% 12-16 years. The majority (92.3%) presented with asymptomatic DVAs identified incidentally. Overall, anatomical distribution revealed predilection for frontal region (42.3%) with other common sites being posterior fossa (17.3%) and basal ganglia (13.5%). Temporal (11.5%), parietal (9.6%) and occipital (5.8%) were the remainder. Associated cavernous malformations (CMs) were present in 3/52 (5.8%), and no DVAs were associated with aneurysms or arteriovenous malformations (AVMs). Three patients had more than one DVA. There were three deaths unrelated to DVAs over median follow-up of 3.8 years. Four patients (7.7%) suffered DVA-related intracranial haemorrhage presenting with neurological deficits. The ages of the children with DVA-related haemorrhages were 21 days, 2 years and 6 months, 7 years and 1 month and 11 years and 7 months. Left-sided DVA haemorrhages predominated (3/4, 75%). The relative risk of a cerebellar DVA haemorrhage compared to its supratentorial counterpart was 5.35 (OR 6.8, 95% CI 0.8-58). DISCUSSION: DVA-related haemorrhage is sevenfold greater in our paediatric cohort compared to adults and is significantly associated with cerebellar location and cavernous malformations. There were no haemorrhages over a median period of 3.8 years of prospective follow-up.


Assuntos
Malformações Arteriovenosas , Veias Cerebrais , Adulto , Cerebelo , Criança , Pré-Escolar , Diagnóstico por Imagem , Feminino , Humanos , Lactente , Recém-Nascido , Hemorragias Intracranianas , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos
11.
Brain Topogr ; 32(3): 492-503, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30895423

RESUMO

Establishing language dominance is an important step in the presurgical evaluation of patients with refractory epilepsy. In the absence of a universally accepted gold-standard non-invasive method to determine language dominance in the preoperative assessment, a range of tools and methodologies have recently received attention. When applied to pediatric age, many of the proposed methods, such as functional magnetic resonance imaging (fMRI), may present some challenges due to the time-varying effects of epileptogenic lesions and of on-going seizures on maturational phenomena. Magnetoencephalography (MEG) has the advantage of being insensitive to the distortive effects of anatomical lesions on brain microvasculature and to differences in the metabolism or vascularization of the developing brain and also provides a less intimidating recording environment for younger children. In this study we investigated the reliability of lateralized synchronous cortical activation during a verb generation task in a group of 28 children (10 males and 18 females, mean age 12 years) with refractory epilepsy who were evaluated for epilepsy surgery. The verb generation task was associated with significant decreases in beta oscillatory power (13-30 Hz) in frontal and temporal lobes. The MEG data were compared with other available presurgical non-invasive data including cortical stimulation, neuropsychological and fMRI data on language lateralization where available. We found that the lateralization of MEG beta power reduction was concordant with language dominance determined by one or more different assessment methods (i.e. cortical stimulation mapping, neuropsychological, fMRI or post-operative data) in 89% of patients. Our data suggest that qualitative hemispheric differences in task-related changes of spectral power could offer a promising insight into the contribution of dominant and non-dominant hemispheres in language processing and may help to characterize the specialization and lateralization of language processes in children.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Epilepsia Resistente a Medicamentos/cirurgia , Lateralidade Funcional , Idioma , Magnetoencefalografia/métodos , Adolescente , Criança , Feminino , Lobo Frontal/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Procedimentos Neurocirúrgicos , Reprodutibilidade dos Testes , Lobo Temporal/fisiologia
12.
Childs Nerv Syst ; 35(12): 2363-2369, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31289855

RESUMO

INTRODUCTION: Consenting paediatric patients for surgical procedures remains inherently unique in that it is underpinned by principles such as parental responsibility, assessment of the child's capacity to consent, and adherence to national/legal guidelines. Quality record keeping is an important objective evidence to demonstrate the highest standards of medical care provided to our patients. The consent form is a crucial medical record encapsulating the attainment of informed consent from a parent/guardian for performing a procedure on their child. We aimed to prospectively evaluate the consenting process in our department to assess adequacy of documentation and parental perspectives. METHODS: A prospective study using qualitative descriptive design was conducted with parents of 50 children requiring neurosurgical procedures over a 3-month period. RESULTS: All patients understood the primary diagnosis and type of surgery. Procedure-specific risks were understood by 98% and 84% could remember the mentioning of general risks of surgery. Only a minority of parents (24%) could recollect that alternative options of management including no treatment were discussed. In cases where relevant, laterality was only documented in 56% of consent forms. All patients felt that an informed decision regarding consent to surgery was made. However, 12% suggested areas where further improvement could be made in the timing of consent and the way information could be better provided. DISCUSSION: Consent is more than a signature on a form. It provides objective evidence of a shared decision-making process between the surgeon, patient, and their parent/guardian. Our initial study highlights multiple areas for improvement.


Assuntos
Termos de Consentimento , Documentação , Consentimento Livre e Esclarecido , Neurocirurgia , Pais , Adolescente , Criança , Compreensão , Feminino , Humanos , Consentimento Informado por Menores , Masculino
13.
Epidemiol Infect ; 145(5): 1037-1043, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28065171

RESUMO

The number of South American camelids (SACs) in England and Wales is increasing and with this comes a risk of new and emerging infections. Although classified as livestock, these animals are also treated as pets and may be in regular contact with humans. This paper reviews zoonotic diseases that have been identified in SACs in England and Wales, and which pose a potential risk to human health. We also highlight the importance of surveillance continuing to capture information on infections in SACs for the protection of both public and animal health.


Assuntos
Camelídeos Americanos , Zoonoses/epidemiologia , Animais , Inglaterra/epidemiologia , País de Gales/epidemiologia
14.
Epidemiol Infect ; 145(12): 2458-2465, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28724455

RESUMO

Recent cases of acute kidney injury due to Seoul hantavirus infection from exposure to wild or pet fancy rats suggest this infection is increasing in prevalence in the UK. We conducted a seroprevalence study in England to estimate cumulative exposure in at-risk groups with contact with domesticated and wild rats to assess risk and inform public health advice. From October 2013 to June 2014, 844 individual blood samples were collected. Hantavirus seroprevalence amongst the pet fancy rat owner group was 34.1% (95% CI 23·9-45·7%) compared with 3·3% (95% CI 1·6-6·0) in a baseline control group, 2·4% in those with occupational exposure to pet fancy rats (95% CI 0·6-5·9) and 1·7% with occupational exposure to wild rats (95% CI 0·2-5·9). Variation in seroprevalence across groups with different exposure suggests that occupational exposure to pet and wild rats carries a very low risk, if any. However incidence of hantavirus infection among pet fancy rat owners/breeders, whether asymptomatic, undiagnosed mild viral illness or more severe disease may be very common and public health advice needs to be targeted to this at-risk group.


Assuntos
Febre Hemorrágica com Síndrome Renal/epidemiologia , Exposição Ocupacional , Doenças dos Roedores/epidemiologia , Vírus Seoul/isolamento & purificação , Adolescente , Adulto , Animais , Inglaterra/epidemiologia , Febre Hemorrágica com Síndrome Renal/virologia , Humanos , Incidência , Pessoa de Meia-Idade , Animais de Estimação , Prevalência , Ratos , Doenças dos Roedores/virologia , Estudos Soroepidemiológicos , Adulto Jovem
16.
Soft Matter ; 12(21): 4709-14, 2016 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-27021920

RESUMO

Stöber silica particles are used in a diverse range of applications. Despite their widespread industrial and scientific uses, information on the internal structure of the particles is non-trivial to obtain and is not often reported. In this work we have used spin-echo small angle neutron scattering (SESANS) in conjunction with ultra small angle X-ray scattering (USAXS) and pycnometry to study an aqueous dispersion of Stöber particles. Our results are in agreement with models which propose that Stöber particles have a porous core, with a significant fraction of the pores inaccessible to solvent. For samples prepared from the same master sample in a range of H2O : D2O ratio solutions we were able to model the SESANS results for the solution series assuming monodisperse, smooth surfaced spheres of radius 83 nm with an internal open pore volume fraction of 32% and a closed pore fraction of 10%. Our results are consistent with USAXS measurements. The protocol developed and discussed here shows that the SESANS technique is a powerful way to investigate particles much larger than those studied using conventional small angle scattering methods.

17.
Phys Chem Chem Phys ; 18(11): 7632-40, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26376836

RESUMO

A comprehensive Raman resonance scattering study of ZnSxSe1-x (ZnSSe) solid solutions over the whole compositional range (0 ≤ x ≤ 1) has been carried out using 325 and 455 nm excitation wavelengths. The Raman scattering intensities of LO ZnS-like and ZnSe-like phonon modes, corresponding to pure S and Se vibrations, respectively, are revealed to be significantly enhanced when excited with 325 nm excitation in the case of S vibrations, and with 455 nm in the case of Se vibrations. This behavior is explained by the interaction of the excitation photons with the corresponding S or Se electronic states in the conduction band, and further confirmed by first principles simulations. These findings advance the fundamental understanding of the coupling between the electronic transitions and photons in the case of Raman resonance effects, and provide inputs for further studies of lattice dynamics, especially in the case of chalcogenide materials. Additionally, the coexistence of modes corresponding to only S vibrations and only Se vibrations in the ZnSSe alloys makes these results applicable for the compositional assessment of ZnSSe compounds.

18.
J Chem Phys ; 145(2): 024303, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27421401

RESUMO

We report the formation of nanoparticles with significant diamond character after UV multi-photon laser excitation of gaseous naphthalene, buffered in static helium gas, at room temperature. The nanoparticles are identified in situ by their absorption and scattering spectra between 400 and 850 nm, which are modeled using Mie theory. Comparisons of the particles' spectroscopic and optical properties with those of carbonaceous materials indicate a sp(3)/sp(2) hybridization ratio of 8:1 of the particles formed. The particle extinction in the closed static (unstirred) gas-phase system exhibits a complex and quasi-oscillatory time dependence for the duration of up to several hours with periods ranging from seconds to many minutes. The extinction dynamics of the system is based on a combination of transport features and particle interaction, predominantly agglomeration. The relatively long period of agglomeration allows for a unique analysis of the agglomeration process of diamond-like carbon nanoparticles in situ.

19.
Global Health ; 12(1): 19, 2016 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-27160242

RESUMO

BACKGROUND: With the recognition of the need for research capacity strengthening for advancing health and development, this research capacity article explores the use of technology enhanced learning in the delivery of a collaborative postgraduate blended Master's degree in Malawi. Two research questions are addressed: (i) Can technology enhanced learning be used to develop health research capacity?, and: (ii) How can learning content be designed that is transferrable across different contexts? METHODS: An explanatory sequential mixed methods design was adopted for the evaluation of technology enhanced learning in the Masters programme. A number of online surveys were administered, student participation in online activities monitored and an independent evaluation of the programme conducted. RESULTS: Remote collaboration and engagement are paramount in the design of a blended learning programme and support was needed for selecting the most appropriate technical tools. Internet access proved problematic despite developing the content around low bandwidth availability and training was required for students and teachers/trainers on the tools used. Varying degrees of engagement with the tools used was recorded, and the support of a learning technologist was needed to navigate through challenges faced. CONCLUSION: Capacity can be built in health research through blended learning programmes. In relation to transferability, the support required institutionally for technology enhanced learning needs to be conceptualised differently from support for face-to-face teaching. Additionally, differences in pedagogical approaches and styles between institutions, as well as existing social norms and values around communication, need to be embedded in the content development if the material is to be used beyond the pilot resource-intensive phase of a project.


Assuntos
Fortalecimento Institucional/métodos , Cooperação Internacional , Invenções/tendências , Aprendizagem , Design de Software , Humanos , Internet , Pesquisa Qualitativa , Apoio à Pesquisa como Assunto/métodos , Apoio à Pesquisa como Assunto/normas , Inquéritos e Questionários
20.
Phys Rev Lett ; 114(1): 016405, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25615487

RESUMO

We report accurate energetics of defects introduced in GaN on doping with divalent metals, focusing on the technologically important case of Mg doping, using a model that takes into consideration both the effect of hole localization and dipolar polarization of the host material, and includes a well-defined reference level. Defect formation and ionization energies show that divalent dopants are counterbalanced in GaN by nitrogen vacancies and not by holes, which explains both the difficulty in achieving p-type conductivity in GaN and the associated major spectroscopic features, including the ubiquitous 3.46 eV photoluminescence line, a characteristic of all lightly divalent-metal-doped GaN materials that has also been shown to occur in pure GaN samples. Our results give a comprehensive explanation for the observed behavior of GaN doped with low concentrations of divalent metals in good agreement with relevant experiment.

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