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61.
62.
Anna N. Boss Abhirup Banerjee Michail Mamalakis Surajit Ray Andrew J. Swift Craig Wilkie Joseph W. Fanstone Bart Vorselaars Joby Cole Simonne Weeks Louise S. Mackenzie 《International journal of molecular sciences》2022,23(13)
Acute kidney injury (AKI) is a prevalent complication in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive inpatients, which is linked to an increased mortality rate compared to patients without AKI. Here we analysed the difference in kidney blood biomarkers in SARS-CoV-2 positive patients with non-fatal or fatal outcome, in order to develop a mortality prediction model for hospitalised SARS-CoV-2 positive patients. A retrospective cohort study including data from suspected SARS-CoV-2 positive patients admitted to a large National Health Service (NHS) Foundation Trust hospital in the Yorkshire and Humber regions, United Kingdom, between 1 March 2020 and 30 August 2020. Hospitalised adult patients (aged ≥ 18 years) with at least one confirmed positive RT-PCR test for SARS-CoV-2 and blood tests of kidney biomarkers within 36 h of the RT-PCR test were included. The main outcome measure was 90-day in-hospital mortality in SARS-CoV-2 infected patients. The logistic regression and random forest (RF) models incorporated six predictors including three routine kidney function tests (sodium, urea; creatinine only in RF), along with age, sex, and ethnicity. The mortality prediction performance of the logistic regression model achieved an area under receiver operating characteristic (AUROC) curve of 0.772 in the test dataset (95% CI: 0.694–0.823), while the RF model attained the AUROC of 0.820 in the same test cohort (95% CI: 0.740–0.870). The resulting validated prediction model is the first to focus on kidney biomarkers specifically on in-hospital mortality over a 90-day period. 相似文献
63.
Previously unexplored resonance conditions are shown to exist for the classical hydrogen atomic system, where the electron
is treated as a classical charged point particle following the nonrelativistic Lorentz-Dirac equation of motion about a stationary
nucleus of opposite charge. For circularly polarized (CP) light directed normal to the orbit, very pronounced subharmonic
resonance behavior is shown to occur with a variety of interesting properties. In particular, only if the amplitude of the
CP light exceeds a critical value, will the resonance continue without radius and energy decay. A perturbation analysis is
carried out to illustrate the main features of the behavior. The present phenomena adds to a growing list of other nonlinear
dynamical behaviors of this simple system, that may well be important for more deeply understanding classical and quantum
connections. 相似文献
64.
In this lead paper for this special section, we advance the perspective that new insights into parenting at risk can be gained by focusing on the dynamic emotional processes that occur during parent–child exchanges, with special emphasis on parental emotions as experienced and their regulation of emotion and underlying cognitions, as well as the role of developmentally rooted cognitions in shaping these associations. We discuss the very few but germinal studies that embody this perspective and introduce work in this section that examines emotion dynamics during parenting in real time. We believe this perspective will move us beyond static conceptualizations of parenting at risk, broadens our understanding of parenting as a process, and accelerates our ability to identify the essential targets of intervention when parenting is at risk. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
65.
The electronic properties of two-dimensional (2D) materials, like graphene, are of considerable fundamental interest. This paper describes how physically adsorbed films probe these properties. The cases of an ideal 2D free electron gas and graphene are examined, with explicit results found for an adsorbed He film. In the free electron case, the scattering is proportional to the 2D structure factor of the film. Results are presented for He on graphene and the free electron gas in both the low coverage and fully commensurate limits. 相似文献
66.
Matthew O.T. Cole 《Automatica》2012,48(9):2377-2380
This paper describes the construction of low-pass FIR filters for application as command input shapers in motion control systems. The filters are designed to operate on an arbitrary command input signal to ensure a finite settling time for system modes with known natural frequency and damping ratio. In addition, the required roll-off rate of the filter frequency response may be prescribed in the design. Excitation of unmodeled high-frequency modes can thereby be reduced. The filters also produce an input-smoothing effect that is useful in situations where discontinuities in the input signal or its derivatives would be detrimental to system performance or function. Numerical case studies are presented to clarify these effects. 相似文献
67.
ABSTRACTThe efficacy of climate-change mitigation policy within the building sector is examined in terms of how fragmentation can limit the extent of mitigation actions that can be achieved in a timely manner. The policy and regulatory context for the building industry is examined in relation to the policy context for solutions and recommendations that will work for all parties. Based on this analysis, two substantive recommendations are made for improved policy design. Firstly, a decoupling of policy objectives and policy mechanisms is needed so that the policy-taking stakeholders (in design, development and construction) can reduce energy use in buildings more effectively. Secondly, policy-taking stakeholders need an explicit and diverse system in order to advocate for policy objectives. The major aspect of this work is the development of a new conceptual framework that ties together these recommendations into a continuous process of policy-making and policy-taking. This framework demonstrates an idealized system that operates simultaneously top down and bottom up, and the development of policy objectives is influenced by stakeholders of all kinds to further the goals of an energy-efficient, low-carbon built environment. 相似文献
68.
Exact solutions are given for the transient temperature in flux-base fins with the method of Green’s functions (GF) in the form of infinite series for three different tip conditions. The speed of convergence is improved by replacing the steady part by a closed-form steady solution. For the insulated-tip case, a quasi-steady solution is presented. Numerical values are presented and the conditions under which the quasi-steady solution is accurate are determined. An experimental example is given for estimation of the heat transfer coefficient (HTC) on a non-rotating roller bearing, in which the outer bearing race is treated as a transient fin. 相似文献
69.
Guided by family interaction theory, this study examined the influences of psychological, peer, and familial processes on alcohol use among young adolescent girls and assessed the contributions of familial factors. An ethnically diverse sample of 1,187 pairs of girls (M age = 12.83 years), and their mothers completed surveys online. Questionnaires assessed girls’ lifetime and recent alcohol use, as well as girls’ demographic, psychological, peer, and family characteristics. Hierarchical logistic regression models showed that although girls’ drinking was associated with a number of psychological and peer factors, the contributions of family domain variables to girls’ drinking were above and beyond that of psychological and peer factors. The interaction analyses further highlighted that having family rules, high family involvement, and greater family communication may offset risks in psychological and peer domains. Study findings underscore the multifaceted etiology of drinking among young adolescent girls and assert the crucial roles of familial processes. Prevention programs should be integrative, target processes at multiple domains, and include work with parents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Issa Ouedraogo Patrice Savadogo Mulualem Tigabu Roy Cole Per Christer Oden Jean-Marie Ouadba 《Landscape Research》2013,38(3):303-320
Forest cover decline is one of the most important environmental issues in the tropics. The present study was carried out in Burkina Faso, West Africa, and aimed at assessing the trajectories of forest cover change and measuring landscape metrics of the trajectory classes in order to better understand the processes of change. Landsat and ASTER images acquired over a period of 30 years were used for cover change detection and the Fragstats package was used to compute landscape metrics with five unifying change classes. Results showed a substantial increase in cropland with concurrent decline in forest cover. Deforestation represented 63% of the Percentage of Landscape (PLAND) in 2006, while reforestation accounted for only 28%. Both of these classes had high Normalized Landscape Shape Index (NLSI) values, indicating that they were present as scattered small patches. The old cultivation (30-year permanent cropland) was aggregated (IJI ≈ 0) while deforestation exhibited highly interspersed patches. The old forest and old cultivation presented lower Area Weighted Fractal Dimension Index (FRAC_AM), but deforestation and reforestation had the higher FRAC_AM. These results confirmed that there was a high level of deforestation and fragmentation in southern Burkina Faso and justify the need for a proper management plan to ensure the sustainable use of forest resources. 相似文献