Random effects models for operational patient pathways

Patient flow modeling is a growing field of interest in health services research. Several techniques have been applied to model movement of patients within and between health-care facilities. However, individual patient experience during the delivery of care has always been overlooked. In this work, a random effects model is introduced to patient flow modeling and applied to a London Hospital Neonatal unit data. In particular, a random effects multinomial logit model is used to capture individual patient trajectories in the process of care with patient frailties modeled as random effects. Intuitively, both operational and clinical patient flow are modeled, the former being physical and the latter latent. Two variants of the model are proposed, one based on mere patient pathways and the other based on patient characteristics. Our technique could identify interesting pathways such as those that result in high probability of death (survival), pathways incurring the least (highest) cost of care or pathways with the least (highest) length of stay. Patient-specific discharge probabilities from the health care system could also be predicted. These are of interest to health-care managers in planning the scarce resources needed to run health-care institutions.     

Tracing ‘driver’ versus ‘modulator’ information flow throughout large-scale,task-related neural circuitry

Primary objective: To determine the relative uses of neural action potential (‘spike’) data versus local field potentials (LFPs) for modeling information flow through complex brain networks. Hypothesis: The common use of LFP data, which are continuous and therefore more mathematically suited for spectral information-flow modeling techniques such as Granger causality analysis, can lead to spurious inferences about whether a given brain area ‘drives’ the spiking in a downstream area. Experiment: We recorded spikes and LFPs from the forelimb motor cortex (M1) and the magnocellular red nucleus (mRN), which receives axon collaterals from M1 projection cells onto its distal dendrites, but not onto its perisomatic regions, as rats performed a skilled reaching task. Results and implications: As predicted, Granger causality analysis on the LFPs—which are mainly composed of vector-summed dendritic currents—produced results that if conventionally interpreted would suggest that the M1 cells drove spike firing in the mRN, whereas analyses of spiking in the two recorded regions revealed no significant correlations. These results suggest that mathematical models of information flow should treat the sampled dendritic activity as more likely to reflect intrinsic dendritic and input-related processing in neural networks, whereas spikes are more likely to provide information about the output of neural network processing.     

Relation between hand grip strength,respiratory muscle strength and spirometric measures in male nursing home residents

Abstract

Adverse-outcomes related to sarcopenia are mostly mentioned as physical disability. As the other skeletal muscles, respiratory muscles may also be affected by sarcopenia. Respiratory muscle strength is known to affect pulmonary functions. Therefore, we aimed to investigate the relations between extremity muscle strength, respiratory muscle strengths and spirometric measures in a group of male nursing home residents. Among a total of 104 male residents, residents with obstructive measures were excluded and final study population was composed of 62 residents. Mean age was 70.5?±?6.7 years, body mass index: 27.7?±?5.3?kg/m² and dominant hand grip strength: 29.7?±?6.5?kg. Hand grip strength was positively correlated with maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) (r?=?0.35, p?<?0.01 and r?=?0.26, p?<?0.05, respectively). In regression analysis, the only factor related to MIP was hand grip strength; among spirometric measures only parameter significantly related to grip strength was peak cough flow (PCF). The association of PCF with grip strength disappeared when MIP alone or “MIP and MEP” were included in the regression analysis. In the latter case, PCF was significantly associated only with MIP. We found peripheric muscle strength be associated with MIP and PCF but not with MEP or any other spirometric parameters. The relation between peripheral muscle strength and PCF was mediated by MIP. Our findings suggest that sarcopenia may affect inspiratory muscle strength earlier or more than the expiratory muscle strength. Sarcopenia may cause decrease in PCF in the elderly, which may stand for some common adverse respiratory complications.     

我国人力资本分布与流动的研究——基于“五普”与“六普”的比较分析

利用中国人口普查资料分析并比较中国人力资本存量和结构的分布现状与变化．阐述了人力资本流动时人力资本分布的影响,结果表明：我国人力资本空间分布不均衡,人力资本流动“俱乐部趋同”现象明显,但人力资本分布结构有收敛趋势。在此基础上提出加强增长极建设,建立人力资本提升机制的政策建议。     

电子易货资源匹配模型研究

针对电子易货市场资源匹配问题,通过系统分析易货市场中资源分类情况以及匹配的目标要求,得到资源匹配的数学模型;运用网络流理论对问题模型进行转化,把资源匹配数量最大的目标转换成有流量限制的网络最小费用流问题,依此建立网络模型;最后,以制造业和服务业之间的易货进行案例分析建模,用winQSB软件求解验证。结果表明,该模型的应用提高了易货资源匹配的运算效率和准确性。     

基于资金流服务商的供应链资金运作能力研究

高效的资金运作能力是决定一个企业乃至一条供应链成功的关键因素。本文提出了资金流服务商这一概念并重点分析了它所具备的两种资金运作能力:资金回收期压缩能力和采购资金占用压缩能力。在一个单周期的报童模型中,研究了资金流服务商通过给制造商提供这两种资金流服务能够给供应链整体收益带来的增大以及在这个过程中二者的利益分配问题。通过进一步比较这两种资金运作能力,验证了各自对于供应链的重要程度。     

徽州、淮北的人口流动与文化传播

作为化外之地的古徽州,因北方长期战乱,引发北人多次南迁,中原世家大族有的徙居徽州,子孙繁衍,聚族而居,徽州也直接继承了中原文明。淮北在北人南下中起了桥梁和中转站的作用,当然也不乏北人留居淮北等。明初政府对淮北凤阳府实行大规模人口迁移政策,晚清太平天国战乱,江南人大量逃亡淮北等地区。这样,淮北成了外来人口杂居的社会。徽州社会长期相对安宁,经济富庶,文化昌荣,文化特色独树一帜。淮北在北宋及之前,虽有北人南下,但自然和人文环境总体尚好,文化名人也层出叠现,对中国文化影响深远。自黄河夺淮入海和金兵犯淮,淮北文化开始凋零荒芜;明初江浙文人的大批迁淮,又使得淮泗文化稍有复苏;至晚清文化持续凋零。     

构建农村人口有序流动的调节机制

农村人口进城所带来的积极效应毋庸置疑,然而由于其流动的无序性,给城乡经济社会发展带来了一定的隐患.农村人口无序流动给农村发展所带来的隐患主要有:“失血般”的人口外流;农村高素质劳动力流失;农业生产力下降;农村养老问题愈加严峻;农村男子往往成为婚姻挤压的牺牲品.农村人口无序流动给城市发展所带来的挑战主要有:城市贫民数量增多;城市住房愈加短缺;城市环境污染加剧;对城市治安管理带来挑战;加重了城市计划生育管理工作的难度;对城市教育资源带来冲击.本文在分析问题的基础上提出了构建农村人口有序流动的调节机制.     

知识生态学视域下的国家创新系统

国家创新系统具有知识生态特征,其中存在着复杂的知识个体、知识链和知识网络,这些知识节点和网络构成了自身以及创新系统的知识环境。在知识环境中,各知识主体之间的知识流动发挥着不同的作用,它们之间的互动效率成为影响国家创新系统效率的因素,可以根据创新主体之间的知识流动分析国家创新系统的效率。     

上市公司现金流操控动机选择研究

对现金流管理的研究是继盈余管理后兴起的管理层舞弊行为研究。在已有关于现金流操控阈值点研究的基础上,以2004年至2009年有分析师预测值的中国上市公司为样本,运用条件分布法,采用统计变量τ和z计算分布频率,并以分布频率直方图直观显示,分析上市公司在现金流量阈值点操控行为的动机选择。从统计结果和分布频率图可知,公司管理层对3个现金流阈值点确实存在不同选择。操控现金流微正的动机最强,即公司管理层更注重报告微正现金流量,其次是超越往年现金流量动机,而迎合分析师预测的动机最弱。研究还发现,管理层存在多重操控动机,即在控制已达到某一个阈值点之后,公司管理层更倾向达到另一个阈值点,存在好上加好的心理。