614 research outputs found

    Atomic layer depostion of TiO2/Al2O3 films for optical applications

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    Atomic layer deposition (ALD) is an important technology for depositing functional coatings on accessible, reactive surfaces with precise control of thickness and nanostructure. Unlike conventional chemical vapour deposition, where growth rate is dependent on reactant flux, ALD employs sequential surface chemical reactions to saturate a surface with a (sub-) monolayer of reactive compounds such as metal alkoxides or covalent halides, followed by reaction with a second compound such as water to deposit coatings layer-by-layer. A judicious choice of reactants and processing conditions ensures that the reactions are self-limiting, resulting in controlled film growth with excellent conformality to the substrate. This paper investigates the deposition and characterisation of multi-layer TiO2 /Al2O3 films on a range of substrates, including silicon , soda glass and polycarbonate, using titanium tetrachloride/water and trimethylaluminium/water as precursor couples. Structure-property correlations were established using a suite of analytical tools, including transmission electron microscopy (TEM), secondary ion mass spectrometry (SIMS), X-ray reflectometry (XRR) and spectroscopic ellipsometry (SE). The evolution of nanostructure and composition of multi-layer high/low refractive index stacks are discussed as a function of deposition parameters

    Hierarchical decline of the initiative and performance of complex activities of daily living in dementia

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    Objectives: While basic activities of daily living hierarchically decline in dementia, little is known about the decline of individual instrumental activities of daily living (IADLs). The objective of this study was to assess initiative and performance deficits in IADLs in dementia. Methods: A total of 581 carers completed the revised Interview for Deterioration in Daily Living Activities in Dementia 2 to rate their relative’s everyday functioning. Results: Initiating and performing IADLs deteriorated hierarchically, while people with dementia were consistently most impaired in initiating using the computer and managing finances. Initiating preparing a cold or hot meal and managing finances were more impaired than their performance, whereas performing maintaining an active social life for example were more impaired than their initiative. Conclusion: Findings can help identify the severity of dementia by understanding deficits in initiative and performance. This study has implications for the development of targeted interventions depending on the stage of dementia

    The Surgical Infection Society revised guidelines on the management of intra-abdominal infection

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    Background: Previous evidence-based guidelines on the management of intra-abdominal infection (IAI) were published by the Surgical Infection Society (SIS) in 1992, 2002, and 2010. At the time the most recent guideline was released, the plan was to update the guideline every five years to ensure the timeliness and appropriateness of the recommendations. Methods: Based on the previous guidelines, the task force outlined a number of topics related to the treatment of patients with IAI and then developed key questions on these various topics. All questions were approached using general and specific literature searches, focusing on articles and other information published since 2008. These publications and additional materials published before 2008 were reviewed by the task force as a whole or by individual subgroups as to relevance to individual questions. Recommendations were developed by a process of iterative consensus, with all task force members voting to accept or reject each recommendation. Grading was based on the GRADE (Grades of Recommendation Assessment, Development, and Evaluation) system; the quality of the evidence was graded as high, moderate, or weak, and the strength of the recommendation was graded as strong or weak. Review of the document was performed by members of the SIS who were not on the task force. After responses were made to all critiques, the document was approved as an official guideline of the SIS by the Executive Council. Results: This guideline summarizes the current recommendations developed by the task force on the treatment of patients who have IAI. Evidence-based recommendations have been made regarding risk assessment in individual patients; source control; the timing, selection, and duration of antimicrobial therapy; and suggested approaches to patients who fail initial therapy. Additional recommendations related to the treatment of pediatric patients with IAI have been included. Summary: The current recommendations of the SIS regarding the treatment of patients with IAI are provided in this guideline

    Is it feasible to deliver a complex intervention to improve the outcome of falls in people with dementia? A protocol for the DIFRID feasibility study

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    Background: People with dementia (PWD) experience ten times as many incident falls as people without dementia. Little is known about how best to deliver services to people with dementia following a fall. We used an integrated, mixed-methods approach to develop a new intervention which combines theory generated via a realist synthesis and data on current provision and pathways, gathered through a prospective observational study as well as qualitative interviews, focus groups, and ethnographic observation. This intervention is to be tested in a feasibility study in the UK National Health Service. Methods: People living with dementia in one of three geographical areas will be eligible for the study if they experience a fall requiring healthcare attention and have an informal carer. Potential participants will be identified by community services (primary care, paramedics, telecare), secondary care (ED; facilitated discharge services; rehabilitation outreach teams) and research case registers. Participants will receive a complex multidisciplinary intervention focused on their goals and interests for up to 12 weeks. The intervention will be delivered by occupational therapists, physiotherapists and rehabilitation support workers. Feasibility outcomes will include recruitment and retention, suitability and acceptability of outcome measures and acceptability, feasibility and fidelity of intervention components. PWD outcome measures will include number of falls, Montreal Cognitive Assessment (MOCA), European Quality of Life Instrument (EQ-5D-5L), Quality of Life–Alzheimer’s Disease Scale (QOL-AD), Modified Falls Efficacy Scale (MFES) and Goal Attainment Scaling (GAS). PWD outcome measures completed by an informal carer will include Disability Assessment for Dementia (DAD), EQ-5D-5L Proxy, QoL-AD Proxy and a Health Utilisation Questionnaire (HUQ), The carer outcome measure will be the Zarit Burden Interview (ZBI). An embedded process evaluation will explore barriers and facilitators to recruitment and intervention delivery. Discussion: The study results will inform whether and how a larger multicentre RCT should be undertaken. A full RCT would have the potential to show how outcomes can be improved for people with dementia who have fallen. Ethics and dissemination: The National Research Ethics Service Committee Newcastle and North Tyneside 2 approved the feasibility study. Trial registration: International Standard Randomised Controlled Trial Registry Registration number: ISRCTN41760734 Date of registration: 16/11/201

    Zinc sulfate as an adjunct to methylphenidate for the treatment of attention deficit hyperactivity disorder in children: A double blind and randomized trial [ISRCTN64132371]

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    BACKGROUND: Attention-deficit hyperactivity disorder is an early-onset, clinically heterogenous disorder of inattention, hyperactivity, and impulsiveness. The diagnosis and treatment of attention-deficit hyperactivity disorder continues to raise controversy, and, there is also an increase in treatment options. In this 6-week double blind, placebo controlled-trial, we assessed the effects of zinc plus methylphenidate in the treatment of children with attention deficit hyperactivity disorder. To the best of our knowledge, this study is the first double blind and placebo controlled clinical trial assessing the adjunctive role of zinc in ADHD. METHODS: Our subjects were 44 outpatient children (26 boys and 18 girls) between the ages of 5–11 (mean ± SD was 7.88 ± 1.67) who clearly met the DSM IV diagnostic criteria for attention-deficit hyperactivity disorder and they were randomized to methylphenidate 1 mg/kg/day + zinc sulfate 55 mg/day (with approximately 15 mg zinc element) (group 1) and methylphenidate 1 mg/kg/day + placebo (sucrose 55 mg) (group 2) for a 6 week double blind clinical trial. The principal measure of the outcome was the Teacher and Parent ADHD Rating Scale. Patients were assessed by a child psychiatrist at baseline, 14, 28 and 42 days after the medication started. RESULTS: The present study shows the Parent and Teacher Rating Scale scores improved with zinc sulfate over this 6-week, double blind and placebo controlled trial. The behavior of the two treatments was not homogeneous across the time. The difference between the two protocols was significant as indicated by the effect on the group, the between-subjects factor (F = 4.15, d.f. = 1, P = 0.04; F = 4.50, d.f. = 1, P = 0.04 respectively). The difference between the two groups in the frequency of side effects was not significant. CONCLUSIONS: This double-blind, placebo-controlled study demonstrated that zinc as a supplementary medication might be beneficial in the treatment of children with attention-deficit hyperactivity disorder. However, further investigations and different doses of zinc are required to replicate these findings in children with ADHD

    Brown fat triglyceride content is associated with cardiovascular risk markers in adults from a tropical region

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    Brown adipose tissue (BAT) is regarded as an interesting potential target for the treatment of obesity, diabetes, and cardiovascular diseases, and the detailed characterization of its structural and functional phenotype could enable an advance in these fields. Most studies evaluating BAT structure and function were performed in temperate climate regions, and we are yet to know how these findings apply to the 40% of the world's population living in tropical areas. Here, we used F-18-fluorodeoxyglucose positron emission tomography - magnetic resonance imaging to evaluate BAT in 45 lean, overweight, and obese volunteers living in a tropical area in Southeast Brazil. We aimed at investigating the associations between BAT activity, volume, metabolic activity, and BAT content of triglycerides with adiposity and cardiovascular risk markers in a sample of adults living in a tropical area and we showed that BAT glucose uptake is not correlated with leanness; instead, BAT triglyceride content is correlated with visceral adiposity and markers of cardiovascular risk. This study expands knowledge regarding the structure and function of BAT in people living in tropical areas. In addition, we provide evidence that BAT triglyceride content could be an interesting marker of cardiovascular risk

    Bimanual grasp planning reflects changing rather than fixed constraint dominance

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    We studied whether motor-control constraints for grasping objects that are moved to new positions reflect a rigid constraint hierarchy or a flexible constraint hierarchy. In two experiments, we asked participants to move two plungers from the same start locations to different target locations (both high, both low, or one high and one low). We found that participants grasped the plungers symmetrically and at heights that ensured comfortable or easy-to-control end postures when the plungers had the same target heights, but these grasp tendencies were reduced when the plungers had different target heights. In addition, when the plungers had different mass distributions, participants behaved in ways that suggested still-different emphases of the relevant grasp constraints. When the plungers had different mass distributions, participants sacrificed bimanual symmetry for end-state comfort. The results suggest that bimanual grasp planning relies on a flexible rather than static hierarchy. Different constraints take on different degrees of importance depending on the nature of the task and on the level of task experience. The results have implications for the understanding of perceptual-motor skill learning. It may be that one mechanism underlying such learning is changing the priorities of task constraints

    Medical students' and facilitators' experiences of an Early Professional Contact course: Active and motivated students, strained facilitators

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    Background: Today, medical students are introduced to patient contact, communication skills, and clinical examination in the preclinical years of the curriculum with the purpose of gaining clinical experience. These courses are often evaluated from the student perspective. Reports with an additional emphasis on the facilitator perspective are scarce. According to constructive alignment, an influential concept from research in higher education, the learning climate between students and teachers is also of great importance. In this paper, we approach the learning climate by studying both students' and facilitators' course experiences.\ud \ud In 2001, a new "Early Professional Contact" longitudinal strand through term 1–4, was introduced at the Sahlgrenska Academy, University of Gothenburg, Sweden. General practitioners and hospital specialists were facilitators.\ud \ud The aim of this study was to assess and analyse students' and clinical facilitators' experiences of the Early Professional Contact course and to illuminate facilitators' working conditions.\ud \ud Methods: Inspired by a Swedish adaptation of the Course Experience Questionnaire, an Early Professional Contact Questionnaire was constructed. In 2003, on the completion of the first longitudinal strand, a student and facilitator version was distributed to 86 students and 21 facilitators. In the analysis, both Chi-square and the Mann-Whitney tests were used.\ud \ud Results: Sixty students (70%) and 15 facilitators (71%) completed the questionnaire. Both students and facilitators were satisfied with the course. Students reported gaining [inspiration] for their future work as doctors along with increased confidence in meeting patients. They also reported increased motivation for biomedical studies. Differences in attitudes between facilitators and students were found. Facilitators experienced a greater workload, less reasonable demands and less support, than students.\ud \ud Conclusion: In this project, a new Early Professional Contact course was analysed from both student and facilitator perspectives. The students experienced the course as providing them with a valuable introduction to the physician's professional role in clinical practice. In contrast, course facilitators often experienced a heavy workload and lack of support, despite thorough preparatory education. A possible conflict between the clinical facilitator's task as educator and member of the workplace is suggested. More research is needed on how doctors combine their professional tasks with work as facilitators
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