623 research outputs found

    Total Patient Delay : A comparison of patient and clinician/health system delays in the diagnosis of progressive supranuclear palsy and corticobasal syndrome

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    Open Access via the Wiley Agreement Research funding PSP Association. Grant Number: CAF/PSP/16/01 Chief Scientist Office, Scottish Government Health and Social Care DirectoratePeer reviewe

    Are Wetland Regulations Cost Effective for Species Protection? A Case Study of Amphibian Metapopulations

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    Recent declines in amphibian populations have raised concern among conservation biologists, with habitat loss and degradation due to human activities among the leading causes. The most common policies used to protect the habitat of pond-breeding amphibians are wetland regulations that safeguard the wetland itself. However, many amphibians spend much of their adult lives foraging and over-wintering in upland habitats and exist as metapopulations with dispersal among ponds. With no consideration of lands in the dispersal matrix, wetland policies may be ineffective at protecting amphibians or other wetland species that disperse across the landscape. This paper examined the adequacy and cost effectiveness of alternative conservation policies and their corresponding land use patterns on the long-term persistence of pond-breeding amphibians in exurban landscapes. We used computer simulations to compare outcomes of wetland buffer policies and broader landscape wide conservation policies across a variety of landscape scenarios, and we conducted sensitivity analyses on the model\u27s species parameters in order to generalize our results to other wetland species. Results showed that, in the majority of human-dominated landscapes, some amount of dispersal matrix protection is necessary for long-term species persistence. However, in landscapes with extremely low-intensity land use (e.g., low-density residential housing) and high pond density, wetland buffer policies may be all that is required. It is not always more cost effective to protect core habitat over the dispersal matrix, a common conservation practice. Conservation costs that result from forgone residential, commercial, or agricultural activities can vary substantially but increase in a nonlinear manner regardless of land use zoning. There appears to be a threshold around an average habitat patch occupancy level of 80%, after which opportunity costs rise dramatically

    Intramolecular palladium-catalyzed alkene carboalkynylation

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    Carbocycles are essential building blocks for the synthesis of natural and synthetic bioactive compounds. Herein, we report the first example of palladium-catalyzed intramolecular carboalkynylation of non-activated olefins. Using activated carbonyl compounds as nucleophiles and an alkynyl bromide as an electrophile, the reaction gives access to cyclopentanes in 44-93% yield and one example of cyclohexane in 31% yield with simultaneous formation of a SP3-SP C-C bond. The reaction therefore combines ring formation with the introduction of a versatile triple bond for further functionalization. (C) 2015 Elsevier Ltd. All rights reserved

    Challenges on the interaction of models and policy for pandemic control.

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    The COVID-19 pandemic has seen infectious disease modelling at the forefront of government decision-making. Models have been widely used throughout the pandemic to estimate pathogen spread and explore the potential impact of different intervention strategies. Infectious disease modellers and policymakers have worked effectively together, but there are many avenues for progress on this interface. In this paper, we identify and discuss seven broad challenges on the interaction of models and policy for pandemic control. We then conclude with suggestions and recommendations for the future

    Complex model calibration through emulation, a worked example for a stochastic epidemic model

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    Uncertainty quantification is a formal paradigm of statistical estimation that aims to account for all uncertainties inherent in the modelling process of real-world complex systems. The methods are directly applicable to stochastic models in epidemiology, however they have thus far not been widely used in this context. In this paper, we provide a tutorial on uncertainty quantification of stochastic epidemic models, aiming to facilitate the use of the uncertainty quantification paradigm for practitioners with other complex stochastic simulators of applied systems. We provide a formal workflow including the important decisions and considerations that need to be taken, and illustrate the methods over a simple stochastic epidemic model of UK SARS-CoV-2 transmission and patient outcome. We also present new approaches to visualisation of outputs from sensitivity analyses and uncertainty quantification more generally in high input and/or output dimensions

    New discrete and polymeric supramolecular architectures derived from dinuclear Co(II), Ni(II) and Cu(II) complexes of aryl-linked bis-beta-diketonato ligands and nitrogen bases: synthetic, structural and high pressure studies

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    New examples of nitrogen base adducts of dinuclear Co(II), Ni(II) and Cu(II) complexes of the doubly deprotonated forms of 1,3-aryl linked bis-β-diketones of type [RC([double bond, length as m-dash]O)CH2C([double bond, length as m-dash]O)C6H4C([double bond, length as m-dash]O)CH2C([double bond, length as m-dash]O)R] (L1H2) incorporating the mono- and difunctional amine bases pyridine (Py), 4-ethylpyridine (EtPy), piperidine (pipi), 1,4-piperazine (pip), N-methylmorpholine (mmorph), 1,4-dimethylpiperazine (dmpip) and N,N,N′,N′-tetramethylethylenediamine (tmen) have been synthesised by reaction of the previously reported [Cu2(L1)2]·2.5THF (R = Me), [Cu2(L1)2(THF)2] (R = t-Bu), [Ni2(L1)2(Py)4] (R = t-Bu) and [Co2(L1)2(Py)4] (R = t-Bu) complexes with individual bases of the above type. Comparative X-ray structural studies involving all ten base adduct derivatives have been obtained and reveal a range of interesting discrete and polymeric molecular architectures. The respective products have the following stoichiometries: [Cu2(L1)2(Py)2]·Py (R = Me), [Cu2(L1)2(EtPy)2]·2EtPy (R = t-Bu), [Cu2(L1)2(pipi)2]·2pipi (R = t-Bu), [Cu2(L1)2(mmorph)2] (R = t-Bu), [Cu2(L1)2(tmen)2] (R = t-Bu) and {[Cu2(L1)2(pip)]·pip·2THF}n, [Co2(L1)2(tmen)2] (R = t-Bu), [Ni2(L1)2(Py)4]·dmpip (R = t-Bu), [Ni2(L1)2(pipi)4]·pipi (R = t-Bu) and [Ni2(L1)2(tmen)2] (R = t-Bu). The effect of pressure on the X-ray structure of [Cu2(L1)2(mmorph)2] has been investigated. An increase in pressure from ambient to 9.1 kbar resulted in modest changes to the unit cell parameters as well as a corresponding decrease of 6.7 percent in the unit cell volume. While a small ‘shearing’ motion occurs between adjacent molecular units throughout the lattice, no existing bonds are broken or new bonds formed

    Repeatability and validity of a standardised maximal step-up test for leg function-a diagnostic accuracy study

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    <p>Abstract</p> <p>Background</p> <p>Objectively assessed physical performance is a strong predictor for morbidity and premature death and there is an increasing interest in the role of sarcopenia in many chronic diseases. There is a need for robust and valid functional tests in clinical practice. Therefore, the repeatability and validity of a newly developed maximal step up test (MST) was assessed.</p> <p>Methods</p> <p>The MST, assessing maximal step-up height (MSH) in 3-cm increments, was evaluated in 60 healthy middle-aged subjects, 30 women and 30 men. The repeatability of MSH and the correlation between MSH and isokinetic knee extension peak torque (IKEPT), self-reported physical function (SF-36, PF), patient demographics and self-reported physical activity were investigated.</p> <p>Results</p> <p>The repeatability between occasions and between testers was 6 cm. MSH (range 12-45 cm) was significantly correlated to IKEPT, (<it>r </it>= 0.68, <it>P </it>< 0.001), SF-36 PF score, (<it>r </it>= 0.29, <it>P </it>= 0.03), sex, age, weight and BMI. The results also show that MSH above 32 cm discriminates subjects in our study with no limitation in self-reported physical function.</p> <p>Conclusions</p> <p>The standardised MST is considered a reliable leg function test for clinical practice. The MSH was related to knee extension strength and self-reported physical function. The precision of the MST for identification of limitations in physical function needs further investigation.</p

    Selective Breeding for a Behavioral Trait Changes Digit Ratio

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    The ratio of the length of the second digit (index finger) divided by the fourth digit (ring finger) tends to be lower in men than in women. This 2D∶4D digit ratio is often used as a proxy for prenatal androgen exposure in studies of human health and behavior. For example, 2D∶4D ratio is lower (i.e. more “masculinized”) in both men and women of greater physical fitness and/or sporting ability. Lab mice have also shown variation in 2D∶4D as a function of uterine environment, and mouse digit ratios seem also to correlate with behavioral traits, including daily activity levels. Selective breeding for increased rates of voluntary exercise (wheel running) in four lines of mice has caused correlated increases in aerobic exercise capacity, circulating corticosterone level, and predatory aggression. Here, we show that this selection regime has also increased 2D∶4D. This apparent “feminization” in mice is opposite to the relationship seen between 2D∶4D and physical fitness in human beings. The present results are difficult to reconcile with the notion that 2D∶4D is an effective proxy for prenatal androgen exposure; instead, it may more accurately reflect effects of glucocorticoids, or other factors that regulate any of many genes
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