288 research outputs found

    Direct and indirect methods for the quantification of leg volume: Comparison between water displacement volumetry, the disk model method and the frustum sign model method, using the correlation coefficient and the limits of agreement

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    Volume changes can be measured either directly by water-displacement volumetry or by various indirect methods in which calculation of the volume is based on circumference measurements. The aim of the present study was to determine the most appropriate indirect method for lower leg volume calculation using water displacement volumetry as a ‘golden standard’. For 20 male volunteers, age range: 20–35 years, the volume of both lower legs was determined directly by water-displacement volumetry, and indirectly by the frustum sign model method and the disc model method. Calculation of the correlation coefficient and the limits of agreement showed that water-displacement volumetry and the disc model method are interchangeable (r = + 0.99, mean ± 2s = − 45 ± 78 ml), whereas this does not hold for the frustum sign model (r = + 0.93, mean ± 2s = 521 ± 238 ml). In the clinical situation volume measurement can be valuable for monitoring of the severity of oedema or haematoma occurrence after surgery or severe trauma. This non-invasive diagnostic aid may be a valuable adjuvant means of diagnosis for several volume dependent disorders of the extremities

    Indicadores do uso sustentável de pesticidas: Onde está a dificuldade?

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    As políticas agrícolas adoptadas na União Europeia e em Portugal têm integrado preocupações ambientais e de saúde pública. A necessidade de avaliar os seus efeitos incorporou a intenção de estabelecer indicadores ambientais nos instrumentos legislativos em vigor para os monitorizar. Em Portugal, diversas entidades têm procurado monitorizar estes efeitos, nomeadamente o uso dos pesticidas, como a Agência Portuguesa do Ambiente (Sistema de Indicadores de Desenvolvimento Sustentável) ou o Instituto de Financiamento da Agricultura e Pescas (Sistema Integrado de Gestão e Controlo). Nos indicadores disponibilizados nada se refere relativamente ao consumo de pesticidas nem a qualquer outro indicador ambiental, como qualidade do solo ou biodiversidade. Todavia, a partir dos registos ao nível do agricultor (cadernos de campo, etc.), recenseamentos e inquéritos, e actividades de investigação e experimentação, poder-se-ia criar um mecanismo simples e expedito que permitisse monitorizar o uso de pesticidas e seus efeitos no ambiente. Será assim tão difícil?...Agroenvironmental policies adopted in the European Union and in Portugal consider environment and human health a major issue. The evaluation of policy effects based on a framework of environmental indicators is referred on multiple legislative documents. In Portugal, several public and private organisms, tried to monitor the agricultural impacts, namely, those related to pesticide use. There isn’t available information related to pesticide consume (the available indicators are based on sales), or to any other environment effect due to pesticide use, as soil quality or biodiversity loss, that would allow an effective assess of impacts caused by agricultural activities. However, farmers, technical and certification organizations, research teams, public services collect systematically information that will be of major help for the establishment of a national indicators framework, that might assess the impacts of pesticide use and risks. Is it so difficult

    The behavior of osteoblast-like cells on various substrates with functional blocking of integrin-β1 and integrin-β3

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    This study was designed to examine the influence of integrin subunit-β1 and subunit-β3 on the behavior of primary osteoblast-like cells, cultured on calcium phosphate (CaP)-coated and non coated titanium (Ti). Osteoblast-like cells were incubated with specific monoclonal antibodies against integrin-β1 and integrin-β3 to block the integrin function. Subsequently, cells were seeded on Ti discs, either non coated or provided with a 2 μm carbonated hydroxyapatite coating using Electrostatic Spray Deposition. Results showed that on CaP coatings, cellular attachment was decreased after a pre-treatment with either anti-integrin-β1 or anti-integrin-β3 antibodies. On Ti, cell adhesion was only slightly affected after a pre-treatment with anti-integrin-β3 antibodies. Scanning electron microscopy showed that on both types of substrate, cellular morphology was not changed after a pre-treatment with either antibody. With quantitative PCR, it was shown for both substrates that mRNA expression of integrin-β1 was increased after a pre-treatment with either anti-integrin-β1 or anti-integrin-β3 antibodies. Furthermore, after a pre-treatment with either antibody, mRNA expression of integrin-β3 and ALP was decreased, on both types of substrate. In conclusion, osteoblast-like cells have the ability to compensate to great extent for the blocking strategy as applied here. Still, integrin-β1 and β3 seem to play different roles in attachment, proliferation, and differentiation of osteoblast-like cells, and responses on CaP-coated substrates differ to non coated Ti. Furthermore, the influence on ALP expression suggests involvement of both integrin subunits in signal transduction for cellular differentiation

    TAML/H2O2 oxidative degradation of metaldehyde: Pursuing better water treatment for the most persistent pollutants.

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    The extremely persistent molluscicide, metaldehyde, widely used on farms and gardens, is often detected in drinking water sources of various countries at concentrations of regulatory concern. Metaldehyde contamination restricts treatment options. Conventional technologies for remediating dilute organics in drinking water, activated carbon and ozone, are insufficiently effective against metaldehyde. Some treatment plants have resorted to effective, but more costly UV/H2O2. Here we have examined if TAML/H2O2 can decompose metaldehyde under laboratory conditions to guide development of a better real world option. TAML/H2O2 slowly degrades metaldehyde to acetaldehyde and acetic acid. Nuclear magnetic resonance spectroscopy ((1)H NMR) was used to monitor the degradation-the technique requires a high metaldehyde concentration (60 ppm). Within the pH range of 6.5-9, the reaction rate is greatest at pH 7. Under optimum conditions, one aliquot of TAML 1a (400 nM) catalyzed 5% degradation over 10 hours with a turnover number of 40. Five sequential TAML aliquots (2 μM overall) effected a 31% removal over 60 hours. TAML/H2O2 degraded metaldehyde steadily over many hours, highlighting an important long-service property. The observation of metaldehyde decomposition under mild conditions provides a further indication that TAML catalysis holds promise for advancing water treatment. These results have turned our attention to more aggressive TAML activators in development, which we expect will advance the observed technical performance

    Beyond chance? The persistence of performance in online poker

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    A major issue in the widespread controversy about the legality of poker and the appropriate taxation of winnings is whether poker should be considered a game of skill or a game of chance. To inform this debate we present an analysis into the role of skill in the performance of online poker players, using a large database with hundreds of millions of player-hand observations from real money ring games at three different stakes levels. We find that players whose earlier profitability was in the top (bottom) deciles perform better (worse) and are substantially more likely to end up in the top (bottom) performance deciles of the following time period. Regression analyses of performance on historical performance and other skill-related proxies provide further evidence for persistence and predictability. Simulations point out that skill dominates chance when performance is measured over 1,500 or more hands of play

    Split or Steal? Cooperative Behavior When the Stakes Are Large

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    We examine cooperative behavior when large sums of money are at stake, using data from the television game show Golden Balls. At the end of each episode, contestants play a variant on the classic prisoner's dilemma for large and widely ranging stakes averaging over $20,000. Cooperation is surprisingly high for amounts that would normally be considered consequential but look tiny in their current context, what we call a “big peanuts” phenomenon. Utilizing the prior interaction among contestants, we find evidence that people have reciprocal preferences. Surprisingly, there is little support for conditional cooperation in our sample. That is, players do not seem to be more likely to cooperate if their opponent might be expected to cooperate. Further, we replicate earlier findings that males are less cooperative than females, but this gender effect reverses for older contestants because men become increasingly cooperative as their age increases

    What affects you? A conversation analysis of exploring emotions during reflection sessions in Dutch general practitioner training

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    IntroductionIn Dutch training for general practitioners (GPs), reflection on professional practice is key to their training. Such reflection is considered beneficial for professional development, especially when it entails discussing the emotional dimension of practice experiences. In the GP context, invitations to share the emotional side of things, such as “how did that make you feel?” are considered functional; yet, they are also sometimes viewed by participants as ‘grilling’, ‘just too much’ or ‘too intimate’. Put shortly, putting emotions on the table is institutionally embedded in the GP reflection context, but not always straightforward. Thus, we ask: ‘how do teachers and GP residents invite talk about emotions in educational reflection sessions?’.MethodsIn this study, we explored the Dutch phrase ‘raken, geraakt worden’ (being affected) as one interactional practice used to initiate emotion talk. We conducted a conversation analytic collection study of instances of this phenomenon based on 40 video recordings of hour-long ‘reflection sessions’ at the Dutch GP specialty training. During these sessions, approximately ten GPs in training discuss recent experiences from medical practice under supervision of one or two teachers.ResultsWe found that participants orientated to the relevance of ‘being affected’ as a topic for discussion. Variations of the form ‘what affects you now?’ may contribute to putting emotions on the table; they can project a stepwise exploration of the emotional dimension of an experience. The ‘what affects you now’, often done in interrogative format doing a noticing, in combination with a request, is a powerful tool to instigate transformative sequences. The form is less effective to put emotions on the table when the topic shift it initiates is not grounded in previously presented personal stakes or displayed emotion.DiscussionThe study’s findings show how detailed interactional analysis of one sequentially structured practice can benefit education and contribute to theory on emotions and reflection. The mobilizing power of ‘what affects you’ can serve institutional purposes by doing topical work in relation to educational aims, while its power can also be deflated when prior talk does not project the relevance of unpacking the emotional dimension of an experience. Its interactional workings may translate to other helping contexts as well

    Platelet autologous growth factors decrease the osteochondral regeneration capability of a collagen-hydroxyapatite scaffold in a sheep model

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    Background: Current research aims to develop innovative approaches to improve chondral and osteochondral regeneration. The objective of this study was to investigate the regenerative potential of platelet-rich plasma (PRP) to enhance the repair process of a collagen-hydroxyapatite scaffold in osteochondral defects in a sheep model. Methods: PRP was added to a new, multi-layer gradient, nanocomposite scaffold that was obtained by nucleating collagen fibrils with hydroxyapatite nanoparticles. Twenty-four osteochondral lesions were created in sheep femoral condyles. The animals were randomised to three treatment groups: scaffold, scaffold loaded with autologous PRP, and empty defect (control). The animals were sacrificed and evaluated six months after surgery. Results: Gross evaluation and histology of the specimens showed good integration of the chondral surface in both treatment groups. Significantly better bone regeneration and cartilage surface reconstruction were observed in the group treated with the scaffold alone. Incomplete bone regeneration and irregular cartilage surface integration were observed in the group treated with the scaffold where PRP was added. In the control group, no bone and cartilage defect healing occurred; defects were filled with fibrous tissue. Quantitative macroscopic and histological score evaluations confirmed the qualitative trends observed. Conclusions: The hydroxyapatite-collagen scaffold enhanced osteochondral lesion repair, but the combination with platelet growth factors did not have an additive effect; on the contrary, PRP administration had a negative effect on the results obtained by disturbing the regenerative process. In the scaffold + PRP group, highly amorphous cartilaginous repair tissue and poorly spatially organised underlying bone tissue were found
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