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141.
142.
The current paper accounts for the influence of intra-specific competition among predators in a prey dependent tri-trophic food chain model of interacting populations. We offer a detailed mathematical analysis of the proposed food chain model to illustrate some of the significant results that has arisen from the interplay of deterministic ecological phenomena and processes. Biologically feasible equilibria of the system are observed and the behaviours of the system around each of them are described. In particular, persistence, stability (local and global) and bifurcation (saddle-node, transcritical, Hopf–Andronov) analysis of this model are obtained. Relevant results from previous well known food chain models are compared with the current findings. Global stability analysis is also carried out by constructing appropriate Lyapunov functions. Numerical simulations show that the present system is capable enough to produce chaotic dynamics when the rate of self-interaction is very low. On the other hand such chaotic behaviour disappears for a certain value of the rate of self interaction. In addition, numerical simulations with experimented parameters values confirm the analytical results and shows that intra-specific competitions bears a potential role in controlling the chaotic dynamics of the system; and thus the role of self interactions in food chain model is illustrated first time. Finally, a discussion of the ecological applications of the analytical and numerical findings concludes the paper. 相似文献
143.
An ecomorphological method was developed, with a focus on predation functions, to define functional groups in the Celtic Sea fish community. Eleven functional traits, measured for 930 individuals from 33 species, led to 11 functional groups. Membership of functional groups was linked to body size and taxonomy. For seven species, there were ontogenetic changes in group membership. When diet composition, expressed as the proportions of different prey types recorded in stomachs, was compared among functional groups, morphology‐based predictions accounted for 28–56% of the interindividual variance in prey type. This was larger than the 12–24% of variance that could be explained solely on the basis of body size. 相似文献
144.
The theme of the 2013 Yale Healthcare Conference was “Partnerships in Healthcare:
Cultivating Collaborative Solutions.” The April conference brought together
leaders across several sectors of health care, including academic research,
pharmaceuticals, information technology, policy, and life sciences investing. In
particular, the breakout session titled “Taking R&D Back to School: The Rise
of Pharma-Academia Alliances” centered on the partnerships between academic
institutions and pharmaceutical companies. Attendees of the session included
members of the pharmaceutical industry, academic researchers, and physicians, as
well as graduate and professional students. The discussion was led by Dr. Thomas
Lynch of Yale University. Several topics emerged from the discussion, including
resources for scientific discovery and the management of competing interests in
collaborations between academia and the pharmaceutical industry. 相似文献
145.
In 2008, one of the worst public health crises occurred in the state of Nevada,
where authorities discovered up to 63,000 patients were potentially exposed to
hepatitis C infection, largely due to substandard infection control and other
negligent practices at two endoscopy clinics in Las Vegas. In the subsequent
grand jury proceedings that followed, it was discovered that several clinic
employees not only participated in these egregious practices, but doctors,
nurses, and other health care professionals witnessed yet failed to report these
incidents, largely due to fears of whistleblower retaliation. In response, the
Nevada state legislature attempted to strengthen whistleblower protection laws,
but it remains unclear if such laws actually protect employees who attempt to
report patient safety concerns. As the push for quality patient outcomes becomes
more prominent with health care reform, whistleblower concerns must be
effectively addressed to ensure that health care professionals can report
patient safety concerns without fear of retaliation. 相似文献
146.
Simon I. Hay Katherine E. Battle David M. Pigott David L. Smith Catherine L. Moyes Samir Bhatt John S. Brownstein Nigel Collier Monica F. Myers Dylan B. George Peter W. Gething 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1614)
The primary aim of this review was to evaluate the state of knowledge of the geographical distribution of all infectious diseases of clinical significance to humans. A systematic review was conducted to enumerate cartographic progress, with respect to the data available for mapping and the methods currently applied. The results helped define the minimum information requirements for mapping infectious disease occurrence, and a quantitative framework for assessing the mapping opportunities for all infectious diseases. This revealed that of 355 infectious diseases identified, 174 (49%) have a strong rationale for mapping and of these only 7 (4%) had been comprehensively mapped. A variety of ambitions, such as the quantification of the global burden of infectious disease, international biosurveillance, assessing the likelihood of infectious disease outbreaks and exploring the propensity for infectious disease evolution and emergence, are limited by these omissions. An overview of the factors hindering progress in disease cartography is provided. It is argued that rapid improvement in the landscape of infectious diseases mapping can be made by embracing non-conventional data sources, automation of geo-positioning and mapping procedures enabled by machine learning and information technology, respectively, in addition to harnessing labour of the volunteer ‘cognitive surplus’ through crowdsourcing. 相似文献
147.
??????? 目的 了解上海市患儿家长对健康教育知识和方式的需求情况,提出做好患儿家长健康教育的方法和途径。方法 在文献检索和专家咨询的基础上,采用自行设计的调查问卷对200名门诊患儿家长和300名住院患儿家长进行调查,并对调查结果进行统计分析。结果 患儿家长对健康教育知识的需求广泛,教育方式的需求多样,对目前开展的健康教育,住院患儿家长的满意度要好于门诊患儿家长,但仍存在一定的不足。 结论 通过满足患儿家长对健康知识的需求、丰富健康教育的形式、加强医护人员人文教育等途径来做好患儿家长的健康教育。 相似文献
148.
Long-term endurance training or physical activity has been confirmed not only to improve physical performance, but to bring about an obvious beneficial effect on human health; however, the mechanism of this effect is not clear. The most studied health adaptations in skeletal muscle response to endurance exercise are increased muscle glycogen level and insulin sensitivity, fiber type transformation toward oxi- dative myofibers, and increased mitochondrial content/function. Mitochondria are dynamic organelles in eukaryotic cells critical in physical performance and disease occurrence. The mitochondrial life cycle spans biogenesis, maintenance, and clearance. Exercise training may promote each of these processes and confer positive impacts on skeletal muscle contractile and metabolic functions. This review focused on the regula- tion of these processes by endurance exercise and discussed its potential benefits in health and disease. We presented evidence suggesting that exercise training potentiates not only the biogenesis of mitochondria but also the removal of old and unhealthy mitochondria through mitochondrial quality control. 相似文献
149.
??????? 目的 了解县级公立医院改革试点医院人力资源配置现状,为合理配置县级公立医院人力资源提供依据。方法 采用现场问卷调查的方法对湖北省12家县级公立医院的960名医护人员进行调查,并对结果进行描述性统计和Spearman秩相关分析 。结果 (1)县级公立医院人力资源数量低于全国平均水平; (2)县级公立医院规模扩张,但是人力资源补给不足;(3)医务人员素质偏低。结论 宏观调控县级公立医院人力资源、促进县级医院的人才引进和培养、增强人力资源质量建设,以提高县级公立医院医疗服务水平。 相似文献
150.
目的比较原代宁乡花猪与其第一代仔猪血液生理生化指标的变化。方法常规方法测定宁乡花猪F0代16头,F1代16头血液18项生理指标和13项生化指标。结果F0代与F1代部分血液生理指标如白细胞(WBC)、红细胞(RBC)、血红蛋白(HGB)、红细胞积压(HCT)等13项有显著性差异(P〈0.05);部分血液生化指标如总胆红素(TBIL),尿素氮(BUN),总蛋白(TP),白/球蛋白(ALB/GLB),葡萄糖(GLU),有显著性差异(P〈0.05);其他指标均无统计学差异。结论2代宁乡花猪之间部分血液生理生化指标有显著性差异。得到的数据可以为实验动物化研究提供相应的基础生理参考数据。 相似文献