866 resultados para BEST AVAILABLE TECHNOLOGY


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By engineering the internal structure of artificial materials it is possible to reproduce effective electromagnetic properties, including some which were previously unavailable in nature. Since the first experimental demonstration of artificial composites with exotic electromagnetic properties at microwaves less than 10 years ago, metamaterials has emerged as a rapidly growing multidisciplinary branch of science and engineering. Significant efforts have been placed in scaling the response of metamaterials to optical frequencies as well as demonstrate pertinent applications of the newly available technology. In this article we review recent developments in the area of experimental realisation of electromagnetic metamaterials and their applications.

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Evidence accumulating from biological and epidemiological studies suggests that high levels of serum cholesterol may promote the pathological processes that lead to Alzheimer's disease (AD). Lowering cholesterol in experimental animal models slows the expression of Alzheimer's pathology. These findings raise the possibility that treating humans with cholesterol lowering medications might reduce the risk of developing AD or help treat it. The statins (lovastatin, pravastatin, simvastatin, and others) are powerful cholesterol lowering agents of proven benefit in vascular disease. Several clinical studies comparing the occurrence of AD between users and non-users of statins suggested that risk of AD was substantially reduced among the users. However, because these studies were not randomized trials, they provided insufficient evidence to recommend statin therapy. Cochrane reviews are based on the best available information about healthcare interventions and they focus primarily on randomized controlled trials (RCTs). On the issue of prevention, two randomized trials have been carried out and neither showed any reduction in occurrence of AD in patients treated with statins compared to those given placebo. Statins cannot therefore be recommended for the prevention of AD. Regarding treatment of AD, the large RCTs which have assessed this outcome have not published their results. Initial analysis from the studies available indicate statins have no benefit on the outcome measure ADAS-Cog but have a significant beneficial effect on MMSE as an outcome. We need to await full results from the RCTs before we can be certain. In addition statins were not detrimental to cognition in either systematic review.

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The ability to teleport entanglement through maximally entangled mixed states as defined by concurrence and linear entropy is studied. We show how the teleported entanglement depends on the quality of the quantum channel used, as defined through its entanglement and mixedness, as well as the form of the target state to be teleported. We present new results based on the fidelity of the teleported state as well as an experimental setup that is immediately implementable with currently available technology.

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This article describes the development, organization, and operation of the Campbell Collaboration, an international network of academics and practitioners who prepare, maintain, and make accessible authoritative systematic reviews of the effectiveness of interventions in the fields of social welfare, education, and criminal justice. The Campbell Collaboration is modeled after the successful Cochrane Collaboration, established in 1993 to produce reviews of the evidence relating to the effectiveness of services in the field of health care. The aim of such reviews is to provide practitioners with a summary of the best available empirical evidence on which to base practice decisions.

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A strong link between research and practice is essential to ensure
that the best available evidence gets into the hands of child welfare
practitioners, who are faced with the daunting task of making decisions
about vulnerable children on a daily basis. In 2007, a group of
senior child welfare leaders in the province of Ontario (Canada) created
a research dissemination model that replicated the worldrenowned
UK program, Research in Practice (http://www.rip.org.
uk). Practice and Research Together (PART; www.partontario.org) is
an Ontario consortium of 45 child welfare organizations whose mandate
is to disseminate research to its member agencies, which include
85% of the local child welfare organizations in the province. Each
member pays an annual membership-fee that is based on its size
(Dill & Shera, 2011). A key factor in PART's success has been its ability
to link its program offerings (i.e., webinars, literature reviews, conferences,
and publications) to issues of real-world relevance to child
welfare practitioners and senior leaders. A central and highly anticipated
program offering is PART's annual conference (learning
event). These conferences bring evidence to bear on practice in priority
areas in child welfare.
On May 31 and June 1 and 2, 2011, PART, in collaboration with the
Centre for Research on Educational and Community Services (CRECS)
at the University of Ottawa, co-hosted an international conference in
Ottawa that was focused on improving the educational achievement
of young people in out-of-home care (hereafter, in care). Speakers
from five countries – Canada, USA, Germany, Sweden, and UK – presented
the results of their research at the conference. The speakers
addressed three main topic areas: the disadvantaged socio-political
status of young people in care, many of whom do not complete secondary
or post-secondary education; innovative interventions to improve
their educational outcomes; and the effectiveness of tutoring,
which is the most common educational intervention for young people
in care.

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Objective: The authors evaluated and synthesised the best-available evidence relating to the effectiveness of CJLD service models with respect to changes in mental health status and/or criminal recidivism.Methods: Research examining the effectiveness of CJLD services when compared to traditional Criminal Justice System (CJS) responses was reviewed and systematically appraised according to Campbell/Cochrane guidelines. Key outcomes included a reduction in offending and post-intervention changes in mental health. Results: Comprehensive searches of published and unpublished literature identified 6571 studies which varied considerably in terms of their methodological approach and overall quality. Ten studies met the inclusion criteria. The synthesised findings indicated that, when compared to traditional CJS outcomes, CJLD services appeared to be effective in terms of identifying MDOs and impacting positively on criminal justice and mental health outcomes.Conclusions: Although the evidence may be deemed to be moderate in terms of methodological rigour, overall, the findings suggest that CJLD services can be beneficial. The effectiveness of services depends upon the model of service delivery, the availability of community services and the engagement of MDOs.The successful implementation of CJLD services requires a clearer recognition of the importance of system of care principles.

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Background: Potentially inappropriate prescribing (PIP) in older people is common in primary care and can result in increased morbidity, adverse drug events, hospitalizations and mortality. The prevalence of PIP in Ireland is estimated at 36% with an associated expenditure of over [euro sign]45 million in 2007. The aim of this paper is to describe the application of the Medical Research Council (MRC) framework to the development of an intervention to decrease PIP in Irish primary care.

Methods: The MRC framework for the design and evaluation of complex interventions guided the development of the study intervention. In the development stage, literature was reviewed and combined with information obtained from experts in the field using a consensus based methodology and patient cases to define the main components of the intervention. In the pilot stage, five GPs tested the proposed intervention. Qualitative interviews were conducted with the GPs to inform the development and implementation of the intervention for the main randomised controlled trial.

Results: The literature review identified PIP criteria for inclusion in the study and two initial intervention components - academic detailing and medicines review supported by therapeutic treatment algorithms. Through patient case studies and a focus group with a group of 8 GPs, these components were refined and a third component of the intervention identified - patient information leaflets. The intervention was tested in a pilot study. In total, eight medicine reviews were conducted across five GP practices. These reviews addressed ten instances of PIP, nine of which were addressed in the form of either a dose reduction or a discontinuation of a targeted medication. Qualitative interviews highlighted that GPs were receptive to the intervention but patient preference and time needed both to prepare for and conduct the medicines review, emerged as potential barriers. Findings from the pilot study allowed further refinement to produce the finalised intervention of academic detailing with a pharmacist, medicines review with web-based therapeutic treatment algorithms and tailored patient information leaflets.

Conclusions: The MRC framework was used in the development of the OPTI-SCRIPT intervention to decrease the level of PIP in primary care in Ireland. Its application ensured that the intervention was developed using the best available evidence, was acceptable to GPs and feasible to deliver in the clinical setting. The effectiveness of this intervention is currently being tested in a pragmatic cluster randomised controlled trial.

Trial registration: Current controlled trials ISRCTN41694007.© 2013 Clyne et al.; licensee BioMed Central Ltd.

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Care Planning in Children and Young People's Nursing addresses a selection of the most common concerns that arise when planning care for infants, children and young people within the hospital and community setting. Clear and detailed, this text reflects both the uniqueness and diversity of contemporary children's nursing and utilizes images and case studies to provide a holistic insight into the practice of care planning through the reporting of best available evidence and current research, policy and education.

Divided into sections for ease of reference, Care Planning in Children and Young People’s Nursing explores both the theory and practice of care planning. Chapters on the principles of care planning include issues such as managing risk, safeguarding children, ethical and legal implications, integrated care pathways, interprofessional assessment, and invaluable parent perspectives. Additional chapters on the application of planning care examine the practical aspects of a wide range of specific conditions including cystic fibrosis, obesity, cardiac/renal failure and HIV/AIDS. Each chapter is interactive, with questions, learning activities and points for discussion creating an engaging and enquiry-based learning approach.

Care Planning in Children and Young People’s Nursing is a definitive resource, reflecting innovative practice which is suitable for undergraduate and postgraduate nurse education.

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RATIONALE, AIMS AND OBJECTIVES: Health care services offered to the public should be based on the best available evidence. We aimed to explore pharmacy tutors' and trainees' views on the importance of evidence when making decisions about over-the-counter (OTC) medicines and also to investigate whether the tutor influenced the trainee in practice.

METHODS: Following ethical approval and piloting, semi-structured interviews were conducted with pharmacy graduates (trainees) and pharmacist tutors. Transcribed interview data were entered into the NVivo software package (version 10), coded and analysed via thematic analysis.

RESULTS: Twelve trainees (five males, seven females) and 11 tutors (five males, six females) participated. Main themes that emerged were (in)consistency and contradiction, confidence, acculturation, and continuation and perpetuation. Despite having an awareness of the importance and potential benefits, an evidence-based approach did not seem to be routinely or consistently implemented in practice. Confidence in products was largely derived from personal use and patient feedback. A lack of discussion about evidence was justified on the basis of not wanting to lessen patient confidence in requested product(s) or possibly negating the placebo effect. Trainees became acculturated to 'real-life' practice; university teaching and evidence was deemed less relevant than meeting customer expectations. The tutor's actions were mirrored by their trainee resulting in continuation and perpetuation of the same professional attitudes and behaviours.

CONCLUSIONS: Evidence appeared to have limited influence on OTC decision making. The tutor played a key role in the trainee's professional development. More work could be performed to investigate how evidence can be regarded as relevant and something that is consistently implemented in practice.

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Stroke survivors often have upper limb (UL) hemiparesis, limiting their ability to perform activities of daily life (ADLs). Intensive, task-oriented exercise therapy (ET) can improve UL function, but motivation to perform sufficient ET is difficult to maintain. Here we report on a trial in which a workstation was deployed in the homes of chronic stroke survivors to enable tele-coaching of ET in the guise of computer games. Participants performed 6 weeks of 1 hour/day, 5 days/week ET. Hand opening and grasp were assisted with functional electrical stimulation (FES). The primary outcome measure was the Action Research Arm Test (ARAT). Secondary outcome measures included a quantitative test of UL function performed on the workstation, grasp force measurements and transcranial magnetic stimulation (TMS). Improvements were seen in the functional tests, but surprisingly, not in the TMS responses. An important finding was that participants commencing with intermediate functional scores improved the most.

CONCLUSIONS: 1) Daily, tele-supervised FES-ET in chronic stroke survivors is feasible with commercially-available technology. 2) The intervention can significantly improve UL function, particularly in people who start with an intermediate level of function. 3) Significant improvements in UL function can occur in the absence of changes in TMS responses.

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Aim:
To demonstrate how systematic reviews provide robust evidence to inform clinical decision making in practice.

Background
Systematic reviews collate findings from a number of research studies in order to provide a comprehensive and reliable summary of the best available evidence. The use of systematic reviews to inform practice based decisions has increased as a result of the overwhelming amount of research literature available, poor quality of research evidence and the need to ensure practice is based upon the best available evidence. Systematic reviews are an efficient way of coping with large volumes of data to answer focused research questions. They differ from traditional literature reviews as they adhere to an explicit scientific process. The use of explicit and rigorous methods to identify, appraise and synthesise relevant studies minimises bias and provides a reliable basis for decision making. As a result systematic reviews provide clear evidence on the effectiveness of a healthcare intervention to inform policy and decision making across healthcare systems. An example of how the findings from systematic reviews can provide reliable evidence to inform healthcare decisions will be provided in this presentation1. This will demonstrate how focused clinical questions can be answered by systematic reviews and translated into practice.

Reference:
1. McGaughey J, Alderdice F, Fowler R, Kapila A, Moutray M. (2007) Outreach and Early Warning Systems (EWS) for the prevention of Intensive Care admission admission and death of critically ill adult patients on general hospital wards (REVIEW). The Cochrane Database of Systematic Reviews 3. art no CD005529

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Background: Unexplained chronic cough (UCC) causes significant quality of life impairment. There is a need to identify effective assessment and treatment approaches for UCC.

Methods: This systematic review of randomized controlled clinical trials asked: What is the efficacy of treatment compared to usual care on cough severity, cough frequency, and cough-related quality of life in patients with unexplained chronic cough (UCC)? Studies of adults and adolescents >12 years with a chronic cough of >8 weeks duration that was unexplained after systematic investigation and treatment were included and assessed for relevance and quality. Based upon the systematic review, guideline suggestions were developed and voted upon using CHEST organization methodology.

Results: 11 RCTs and 5 systematic reviews were included. The 11 RCTs reported data on 570 participants with chronic cough who received a variety of interventions. Study quality was high in 10 RCTs. The studies used a variety of descriptors and assessments to identify unexplained chronic cough. While gabapentin and morphine showed positive effects on cough-related quality of life, only gabapentin was supported as a treatment recommendation. Studies of inhaled corticosteroids (ICS) suffered from intervention fidelity bias, and when this was addressed, ICS were not found to be effective for UCC. Esomeprazole was not effective for UCC without features of gastroesophageal acid reflux. Studies addressing non-acid gastroesophageal reflux were not identified. A multimodality speech pathology intervention improved cough severity.

Conclusions: The evidence supporting the diagnosis and management of UCC is limited. UCC requires further study to establish agreed terminology and the optimal methods of investigation using established criteria for intervention fidelity. Speech pathology based cough suppression is suggested as a treatment option for UCC. This guideline presents suggestions for diagnosis and treatment based on the best available evidence and identifies gaps in our knowledge and areas for future research.

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Esta tese descreve diversas estratégias preparativas assim como estudos de caracterização de nanocompósitos e outras nanoestruturas, para a análise em espectroscopia de Raman com intensificação por superfície (SERS). Em particular foi estudada a incorporação de nanopartículas (NPs) metálicas de Ag e Au em matrizes poliméricas visando avaliar o potencial destes materiais como novos substratos para SERS na deteção de moléculas. O primeiro capítulo consiste numa revisão bibliográfica, onde é destacado o desenvolvimento de novos substratos para SERS utilizando nomeadamente nanopartículas de Ag, Au e Cu. Numa primeira fase, esta secção apresenta uma breve descrição sobre as propriedades plasmónicas dos metais utilizados e alguns conceitos básicos de espectroscopia de difusão de Raman. Posteriormente, descreve-se em mais detalhe o efeito de SERS, revendo-se sobretudo a química de materiais descrita em trabalhos recentes tendo em conta a sua utilização como novas plataformas para análise química por SERS. O capítulo 2 descreve a síntese e caracterização de nanocompósitos de poli(acrilato de butilo) obtidos através de polimerização in situ por miniemulsão na presença de nanopartículas de Ag. Os nanocompósitos Ag/PtBA foram investigados como novos substratos de SERS visando o desenvolvimento de novas plataformas versáteis para deteção molecular. Estudos como o efeito da temperatura, pH e pressão foram investigados, visando a compreensão do efeito da matriz polimérica na difusão/adsorção do analito (ácido tiossalicílico) na superfície metálica. No capítulo 3, os nanocompósitos de Ag/PtBA descritos anteriormente foram investigados detalhadamente como substratos para bio-deteção em SERS, usando a adenina como analito modelo. Os nanocompósitos foram submetidos a vários tratamentos pré-analíticos para a bio-deteção da adenina. Foram realizadas experiências nos sistemas Ag/PtBA de modo a obter informação sobre o efeito do pH na deteção deste analito em soluções aquosas diluídas. Os nanocompósitos poliméricos obtidos apresentam a vantagem de poderem ser processados utilizando tecnologia disponível. Pelo que o estudo das suas propriedades térmicas é especialmente relevante. Assim, a influência da incorporação de NPs inorgânicas na temperatura de transição vítrea (Tg) do polímero PtBA foi investigada por meio de calorimetria diferencial de varrimento (DSC) e os resultados são apresentados no capítulo 4. Estes estudos descrevem efeitos na Tg do PtBA quando analisado em nanocompósitos obtidos por diferentes métodos (métodos ex situ e in situ), contendo nanopartículas metálicas com diferentes distribuições de tamanho e presentes em quantidade variável na matriz polimérica. Estes estudos possibilitaram relacionar a influência das NPs metálicas na mobilidade das cadeias poliméricas com as propriedades térmicas observadas. O capítulo 5 descreve a preparação e caracterização de materiais compósitos de base polimérica (PtBA) e NPs de Au com morfologia de bastonetes (NRs). Estes materiais foram investigados como substratos para SERS tendo originado um bom sinal de SERS na análise de 2-2’-ditiodipiridina. Investigouse igualmente o efeito da variação da morfologia das NPs metálicas (esferas e bastonetes), a razão de aspecto (R.A.) dos bastonetes e o tipo de matriz polimérica (PtBA e PnBA) no sinal de SERS. No capítulo 6 é descrita a utilização da técnica de SERS como método alternativo para a monitorização de alterações morfológicas de coloides de NRs de Au. Os NRs de Au foram recolhidos em diferentes fases de oxidação promovida pela presença de K2S2O8 e a sua sensibilidade como substratos de SERS foi avaliada utilizando o anião dietilditiocarbamato (DTC) como analito modelo. Os estudos foram realizados utilizando as linhas de excitação a 1064 nm e 633 nm. Este estudo demonstrou que a sensibilidade dos NRs de Au como substratos de SERS diminui à medida que a sua R.A. diminui devido à competitividade do CTAB (estabilizante) e o DTC pela superfície dos NRs. É de salientar que este processo é acompanhado por um diferente comportamento em termos de adsorção dos dois tautómeros do DTC à superfície do metal. O capítulo 7 introduz um novo tipo de compósitos para SERS, utilizando matrizes biopoliméricas. Assim, descreve-se a preparação e caracterização de nanocompósitos de carragenano e NPs de Ag. Nesta secção é avaliada a utilização destes materiais como novos substratos para a análise em SERS, utilizando a 2-2’-ditiodipiridina como molécula modelo. Descrevem-se estudos pioneiros que procuram relacionar a dependência do sinal de SERS com a força do gel. Para tal, realizou-se um estudo sistemático aos nanobiocompósitos usados como substratos de SERS em diferentes condições analíticas e investigaram-se as suas propriedades reológicas. No capitulo 8 é descrita a investigação de nanocompósitos de Ag/Gelatina como substratos para SERS, utilizando o anião dietilditiocarbamato como analito modelo. Realizaram-se várias experiências para correlacionar a variação da força do gel com o aumento do sinal de SERS bem como a diferente adsorção dos dois tautómeros do DTC à superfície do metal. Ao longo desta dissertação são apresentados metodologias distintas para a preparação e obtenção de nanocompósitos com base em polímeros (sintéticos ou naturais) e NPs metálicas (Ag e Au). Esta investigação não só permitiu a síntese e estudo de novos substratos para SERS mas também a compreensão do efeito matriz/NPs metálicas no sinal de SERS e na formação de “hot spots”. Este trabalho contribui para o enriquecimento na área da Nanociência e Nanotecnologia demonstrando a eficácia e reprodutibilidade de nanocompósitos com base em polímeros como novos substratos para SERS. Embora as propriedades óticas apresentadas por estes materiais serem aqui direcionadas para a deteção molecular pela técnica de SERS, estes materiais podem ser investigados em outras área tecnológicas.

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Tese de mestrado integrado em Engenharia da Energia e do Ambiente, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2016

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The paper introduces an approach to solve the problem of generating a sequence of jobs that minimizes the total weighted tardiness for a set of jobs to be processed in a single machine. An Ant Colony System based algorithm is validated with benchmark problems available in the OR library. The obtained results were compared with the best available results and were found to be nearer to the optimal. The obtained computational results allowed concluding on their efficiency and effectiveness.