A Coupled FEM-BEM Approach for the Solution of the Free-Boundary Axi-Symmetric Plasma Equilibrium Problem

In this paper we present a coupled Finite Element Method – Boundary Element Method (FEM-BEM) approach for the solution of the free-boundary axi-symmetric plasma equilibrium problem. The proposed method, obtained from an improvement of the Hagenow-Lackner coupling method, allows to efficiently model the equilibrium problem in unbounded domains by discretizing only the plasma region; the external conductors can be modelled either as 2D or 3D models, according to the problem of interest. The paper explores different iterative methods for the solution of the nonlinear Grad-Shafranov equation, such as Picard, Newton-Raphson and Newton-Krylov, in order to provide a robust and reliable tool, able to handle large-scale problems (e.g. high resolution equilibria). This method has been implemented in the FRIDA code (FRee-boundary Integro-Differential Axisimmetric – https://github. om/matteobonotto/ FRIDA), together with a suitable Adaptive Integration Technique (AIT) for the computation of the source term. FRIDA has been successfully tested and validated against experimental data from RFX-mod device, and numerical equilibria of an ITER-like device.     

Residential greenness and risks of depression: Longitudinal associations with different greenness indicators and spatial scales in a Finnish population cohort

We carried out a longitudinal study on the associations between residential greenness and depression risk in urban areas in Finland. Residential greenness indicators were estimated within various buffer sizes around individuals' home locations (selected n = 14424) using time-series of normalized differential vegetation index (NDVI) and CORINE land cover data (CLC). We estimated individuals’ cumulative exposure to residential greenness over a 5-years and 14-years follow-up. We used doctor-diagnosed depression and Beck Depression Inventory for depression assessment. Our multi-logistic model showed an inverse association between residential greenness and depression, implying lowered depression risk for individuals with higher residential greenness. The association was particularly evident when using NDVI-based residential greenness (within a buffer of 100 m radius) and doctor-diagnosis depression data, adjusted with individual-level covariates. The odds ratio was 0.56 (95% CI 0.33 to 0.96) for the 5-years follow-up, and 0.54 (95% CI 0.30 to 0.98) for the 14-years follow-up. The associations between CLC-based total residential green space and depression varied across the different buffer sizes. In general, all the associations depended on the type of depression assessment, quality of greenness indicators, and the spatial scale of analysis. The associations also varied across the socio-demographic groups and neighborhood socioeconomic disadvantage level.     

空间统计学在食品污染物分布研究中的应用

目的 以2017年某省食品安全监测大米中砷含量数据为例，探讨空间统计学方法在食品污染物分析中的应用价值。方法 采用空间点模式估计、核密度分析，全局以及局部自相关性分析等空间统计学方法，在县级空间尺度下，对某省大米中砷含量进行探索性空间数据分析。结果 空间点模式分布图显示，该省大米砷污染的空间分布比较分散，核密度分析结果显示污染热点区域主要在该省中东部地区。全局自相关Moran''s I指数值为0.11，有统计学意义，大米样品中砷污染呈现出低度空间聚集性。有1个"高-高"聚集区，2个典型的"低-低"聚集区。结论 空间统计学运用于食物污染物分布研究上，可以很好地可视化展示、识别污染分布规律、热点地区和聚集区，为基于问题的监测工作的开展提供技术支持。     

基于平均最邻近和缓冲区分析方法的预防接种门诊空间分布特征分析

目的从空间角度分析黔南州预防接种门诊分布特征情况,为卫生资源的优化配置提供依据。方法采用平均最邻近和缓存区分析研究区域内预防接种门诊的空间分布模式以及服务范围。结果研究区域内预防接种门诊空间分布格局呈随机分布,预防接种服务最大服务范围未覆盖所有区域,其中预防接种门诊服务覆盖面积占比,长顺县最高为99.95%,独山县最低为83.12%。结论平均最邻近和缓冲区分析方法能直观地展示预防接种门诊空间分布特征以及测量服务范围,为合理设置预防接种门诊的提供参考依据。     

A novel fMRI paradigm to dissociate the behavioral and neural components of mixed‐strategy decision making from non‐strategic decisions in humans

During competitive interactions, such as predator–prey or team sports, the outcome of one's actions is dependent on both their own choices and those of their opponents. Success in these rivalries requires that individuals choose dynamically and unpredictably, often adopting a mixed strategy. Understanding the neural basis of strategic decision making is complicated by the fact that it recruits various cognitive processes that are often shared with non‐strategic forms of decision making, such as value estimation, working memory, response inhibition, response selection, and reward processes. Although researchers have explored neural activity within key brain regions during mixed‐strategy games, how brain activity differs in the context of strategic interactions versus non‐strategic choices is not well understood. We developed a novel behavioral paradigm to dissociate choice behavior during mixed‐strategy interactions from non‐strategic choices, and we used task‐based functional magnetic resonance imaging (fMRI) to contrast brain activation. In a block design, participants competed in the classic mixed‐strategy game, “matching pennies,” against a dynamic computer opponent designed to exploit predictability in players’ response patterns. Results were contrasted with a non‐strategic task that had comparable sensory input, motor output, and reward rate; thus, differences in behavior and brain activation reflect strategic processes. The mixed‐strategy game was associated with activation of a distributed cortico‐striatal network compared to the non‐strategic task. We propose that choosing in mixed‐strategy contexts requires additional cognitive demands present to a lesser degree during the control task, illustrating the strength of this design in probing function of cognitive systems beyond core sensory, motor, and reward processes.     

2004－2016年我国结核病流行的时空特征分析

目的 分析2004-2016年我国结核病登记病例的时空分布特征,探测聚集区域,为结核病防控提供理论依据。方法 利用ArcGIS 10.0软件作为数据管理和呈现的平台,建立我国2004-2016年结核病空间分析数据库,对结核病疫情进行空间自相关分析,采用SaTScan 9.6软件进行时空扫描分析。结果 2004-2016年全国共登记结核病病例13 157 794例,全国年均登记率为75.90/10万(27.95/10万~180.82/10万)。全局空间自相关结果显示结核病发病呈聚集性分布,局部Moran''s I自相关分析结果表明,新疆、西藏、贵州、广西和海南(省、自治区)为高-高聚集区域,北京、河北、天津、山东、江苏、上海(省、直辖市)为低-低聚集区域;局部G统计量热点分析结果显示,全国结核病疫情存在15个"热点"区域,其中3个"正热点"区域分别为新疆、西藏和海南(省、自治区), 12个"负热点"区域分别为北京、天津、辽宁、内蒙古、河北、山东、江苏、安徽、上海、山西、河南和吉林(省、自治区、直辖市)。利用SaTScan 9.6软件进行分阶段时空扫描分析,3个阶段共探测出12个聚集区域,每个聚集区域差异均有统计学意义(均P<0.05)。结论 2004-2016年我国结核病疫情呈现逐年下降的趋势,各省(自治区、直辖市)的年均登记率并非随机分布,呈明显的空间聚集性,分阶段时空扫描聚集区域逐渐减少,结核病防治工作取得一定进展,但高风险地区仍持续存在,需重点关注并采取针对性防控措施。