2,222 research outputs found

    Exploring the performance of molecular rectifiers: Limitations and factors affecting molecular rectification

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    There has been significant work investigating the use of molecules as nanoscale rectifiers in so-called "molecular electronics". However, less attention has been paid to optimizing the design parameters of molecular rectifiers or to their inherent limitations. Here we use a barrier tunneling model to examine the degree of rectification that can be achieved and to provide insight for the design and development of molecules with optimum rectification responses. © 2007 American Chemical Society

    Cuprizone demyelination of the corpus callosum in mice correlates with altered social interaction and impaired bilateral sensorimotor coordination

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    For studies of remyelination in demyelinating diseases, the cuprizone model of CC (corpus callosum) demyelination has experimental advantages that include overall size, proximity to neural stem cells of the subventricular zone, and correlation with a lesion predilection site in multiple sclerosis. In addition, cuprizone treatment can be ended to allow more direct analysis of remyelination than with viral or autoimmune models. However, CC demyelination lacks a useful functional correlate in rodents for longitudinal analysis throughout the course of demyelination and remyelination. In the present study, we tested two distinct behavioural measurements in mice fed 0.2% cuprizone. Running on a ‘complex' wheel with varied rung intervals requires integration between cerebral hemispheres for rapid bilateral sensorimotor coordination. Maximum running velocity on the ‘complex' wheel decreased during acute (6 week) and chronic (12 week) cuprizone demyelination. Running velocity on the complex wheel distinguished treated (for 6 weeks) from non-treated mice, even after a 6-week recovery period for spontaneous remyelination. A second behavioural assessment was a resident–intruder test of social interaction. The frequency of interactive behaviours increased among resident mice after acute or chronic demyelination. Differences in both sensorimotor coordination and social interaction correlated with demonstrated CC demyelination. The wheel assay is applicable for longitudinal studies. The resident–intruder assay provides a complementary assessment of a distinct modality at a specific time point. These behavioural measurements are sufficiently robust for small cohorts as a non-invasive assessment of demyelination to facilitate analysis of subsequent remyelination. These measurements may also identify CC involvement in other mouse models of central nervous system injuries and disorders

    An exploratory cluster randomised controlled trial of knowledge translation strategies to support evidence-informed decision-making in local governments (The KT4LG study)

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    Background: Childhood overweight and obesity is the most prevalent and, arguably, politically complex child health problem internationally. Governments, communities and industry have important roles to play, and are increasingly expected to deliver an evidence-informed system-wide prevention program. However, efforts are impeded by a lack of organisational access to and use of research evidence. This study aims to identify feasible, acceptable and ideally, effective knowledge translation (KT) strategies to increase evidence-informed decision making in local governments, within the context of childhood obesity prevention as a national policy priority.Methods/Design: This paper describes the methods for KT4LG, a cluster randomised controlled trial which is exploratory in nature, given the limited evidence base and methodological advances. KT4LG aims to examine a program of KT strategies to increase the use of research evidence in informing public health decisions in local governments. KT4LG will also assess the feasibility and acceptability of the intervention. The intervention program comprises a facilitated program of evidence awareness, access to tailored research evidence, critical appraisal skills development, networking and evidence summaries and will be compared to provision of evidence summaries alone in the control program. 28 local governments were randomised to intervention or control, using computer generated numbers, stratified by budget tertile (high, medium or low). Questionnaires will be used to measure impact, costs, and outcomes, and key informant interviews will be used to examine processes, feasibility, and experiences. Policy tracer studies will be included to examine impact of intervention on policies within relevant government policy documents.Discussion: Knowledge translation intervention studies with a focus on public health and prevention are very few in number. Thus, this study will provide essential data on the experience of program implementation and evaluation of a system-integrated intervention program employed within the local government public health context. Standardised programs of system, organisational and individual KT strategies have not been described or rigorously evaluated. As such, the findings will make a significant contribution to understanding whether a facilitated program of KT strategies hold promise for facilitating evidence-informed public health decision making within complex multisectoral government organisations.<br /

    Changes in body weight and food choice in those attempting smoking cessation: a cluster randomised controlled trial

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    &lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; Fear of weight gain is a barrier to smoking cessation and significant cause of relapse for many people. The provision of nutritional advice as part of a smoking cessation programme may assist some in smoking cessation and perhaps limit weight gain. The aim of this study was to determine the effect of a structured programme of dietary advice on weight change and food choice, in adults attempting smoking cessation.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Methods:&lt;/b&gt; Cluster randomised controlled design. Classes randomised to intervention commenced a 24-week intervention, focussed on improving food choice and minimising weight gain. Classes randomised to control received "usual care".&lt;/p&gt; &lt;p&gt;&lt;b&gt;Results:&lt;/b&gt; Twenty-seven classes in Greater Glasgow were randomised between January and August 2008. Analysis, including those who continued to smoke, showed that actual weight gain and percentage weight gain was similar in both groups. Examination of data for those successful at giving up smoking showed greater mean weight gain in intervention subjects (3.9 (SD 3.1) vs. 2.7 (SD 3.7) kg). Between group differences were not significant (p=0.23, 95% CI -0.9 to 3.5). In comparison to baseline improved consumption of fruit and vegetables and breakfast cereal were reported in the intervention group. A higher percentage of control participants continued smoking (74% vs. 66%).&lt;/p&gt; &lt;p&gt;&lt;b&gt;Conclusions:&lt;/b&gt; The intervention was not successful at minimising weight gain in comparison to control but was successful in facilitating some sustained improvements in the dietary habits of intervention participants. Improved quit rates in the intervention group suggest that continued contact with advisors may have reduced anxieties regarding weight gain and encouraged cessation despite weight gain. Research should continue in this area as evidence suggests that the negative effects of obesity could outweigh the health benefits achieved through reductions in smoking prevalence.&lt;/p&gt

    Automatic belief network modeling via policy inference for SDN fault localization

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    A tool for examining the role of the zinc finger myelin transcription factor 1 (Myt1) in neural development: Myt1 knock-in mice

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    The Myt1 family of transcription factors is unique among the many classes of zinc finger proteins in how the zinc-stabilized fingers contact the DNA helix. To examine the function of Myt1 in the developing nervous system, we generated mice in which Myt1 expression was replaced by an enhanced Green Fluorescent Protein fused to a Codon-improved Cre recombinase as a protein reporter. Myt1 knock-in mice die at birth, apparently due to improper innervation of their lungs. Elimination of Myt1 did not significantly affect the number or distribution of neural precursor cells that normally express Myt1 in the embryonic spinal cord. Nor was the general pattern of differentiated neurons altered in the embryonic spinal cord. The Myt1 knock-in mice should provide an important tool for identifying the in vivo targets of Myt1 action and unraveling the role of this structurally distinct zinc finger protein in neural development

    Risk factors for hospitalisation and poor outcome with pandemic A/H1N1 influenza: United Kingdom first wave (May–September 2009)

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    Pandemic H1N1 infection causes disease requiring hospitalisation of previously fit individuals as well as those with underlying conditions. An abnormal chest x-ray or a raised CRP level, especially in patients who are recorded as obese or who have pulmonary conditions other than asthma or COPD, indicate a potentially serious outcome. These findings support the use of pandemic vaccine in pregnant women, children &lt;5 years of age and those with chronic lung diseas

    Colour response in western flower thrips varies intraspecifically

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    Discrepancies in the published research as to the attraction of the economically important pest western flower thrips (WFT) to different colours confounds the optimisation of field traps for pest management purposes. We considered whether the different experimental conditions of independent studies could have contributed to this. Therefore, the behavioural response (i.e., landings) to different colour cues of two WFT laboratory populations from Germany (DE) and The Netherlands (NL), which had previously been independently shown to have different colour preferences, were tested in the same place, and under the same experimental conditions. Single-choice wind tunnel bioassays supported previous independent findings, with more of a NL population landing on the yellow LED lamp (588 nm) than the blue (470 nm) (p = 0.022), and a not-statistically significant trend observed in a DE population landing more on blue compared to yellow (p = 0.104). To account for potential original host rearing influences, both populations were subsequently established on bean for ~20 weeks, then yellow chrysanthemum for 4–8 and 12–14 weeks and tested in wind tunnel choice bioassays. Laboratory of origin, irrespective of the host plant rearing regime, remained a significant effect (p < 0.001), with 65% of the NL WFT landing on yellow compared to blue (35%), while 66% of the DE WFT landed on blue compared to yellow (34%). There was also a significant host plant effect (p < 0.001), with increased response to yellow independent of laboratory of origin after rearing on chrysanthemum for 12–14 weeks. Results suggest that differing responses of WFT populations to colour is, in this case, independent of the experimental situation. Long-term separate isolation from the wild cannot be excluded as a cause, and the implications of this for optimising the trap colour is discussed
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