Path integration: is there a difference between athletes and non-athletes?

The ability to estimate distance walked when blindfolded is associated with the vestibular, proprioceptive and (loco-)motor systems. In this study, we examined subjects’ ability to walk when blindfolded to a previously seen target. We examined whether there is a difference of performance in path integration between athletes and non-athletes. Two groups of healthy volunteers took part in this experiment: 21 athletes and 20 non-athletes. Subjects were asked to walk at three different velocities (slow, normal, fast) to a target (10 m in front of them) that they had seen before being blindfolded. Increase in velocity was associated with a decrease in the distance walked for both groups. Both groups were accurate at normal velocities. Athletes were also accurate at fast velocities whereas non-athletes undershot the target. In both groups, accuracy considerably decreased at slow velocities. It seems that our perceptual system can adapt to different velocities (normal, fast) but is most strongly disrupted at low velocity. When attempting to modify walking velocity, step length is also modified, playing a determining role in the estimation of distance.     

新疆维吾尔族早发冠心病患者疾病认知率的影响因素分析

目的：探讨新疆地区维吾尔族早发冠心病患者对冠心病相关知识的认知率及影响认知的因素,以指导对患者进行个性化健康宣传教育工作。方法随机抽取我院门诊及住院治疗的120例维吾尔族早发冠心病患者作为调查对象,使用自行设计的调查问卷进行调查,分析调查对象对冠心病相关知识知晓率及其影响因素。结果维吾尔族早发冠心病患者对冠心病相关知识的认知率相对较低,平均得分为（27.17±6.12）分,平均得分率为45.32%;不同性别、文化程度、病程、收入水平、报销方式、婚姻状况、家庭关心程度之间在疾病认知水平上差异有统计学意义（P <0.05）;路径分析结果显示：影响维吾尔族早发冠心病患者认知情况的因素从大到小为：文化程度、报销方式、收入水平、家属关心、婚姻以及性别。结论对于低学历、低收入、公费、家庭关心程度低、女性的维吾尔族早发冠心病患者应引起足够的重视,在入院时即进行规范的健康教育,从而较快、较好地提高新疆维吾尔族早发冠心病患者对此疾病的认知水平,改善预后、预后再次发生,减少医疗费用等。     

宿舍环境与文化对大学生睡眠的影响及其机制研究

目的 了解大学生宿舍睡眠环境现状,探索宿舍环境和宿舍文化对大学生睡眠的影响机制,为提高大学生睡眠质量提供参考.方法 使用匹兹堡睡眠质量指数（PSQI）量表和自行设计的问卷,通过整群抽样对北京市某大学医学专业本科生进行调查.结果 调查对象睡眠障碍发生率为22.6％,41.7％的学生认为宿舍睡眠环境对自己睡眠质量的影响大,不同宿舍环境下的学生匹兹堡睡眠质量指数差异具有统计学意义（P＜0.01）.通径分析显示,宿舍文化通过宿舍睡眠环境这一中间变量对大学生睡眠质量产生影响.结论 人际关系、矛盾冲突、宿舍睡眠规则等宿舍文化因素会影响到成员对宿舍睡眠环境的评价,而宿舍环境会对成员的睡眠质量产生影响.     

晚期血吸虫病伤残权重的初步评定及影响因素分析

目的 发展适合我国晚期血吸虫病疾病负担评价的伤残权重,并分析伤残权重的影响因素,为评估其疾病负担提供参考依据. 方法 以全球疾病负担研究中疾病的六级失能等级标准为依据,评定我国晚期血吸虫病的年龄别和性别平均伤残权重.通过问卷调查的方式对湖北省阳新县125例晚期血吸虫病患者进行调查,全部数据采用EpiData3.1软件建库,应用SAS8.1软件进行分析.分别采用Wilcoxon秩和检验、Kruskal-Wallis秩和检验比较性别和年龄别伤残权重,用Nemenyi法对年龄别伤残权重进行两两比较,并通过通径分析模型分析伤残权重的影响因素. 结果 我国湖区晚期血吸虫病患者伤残权重均值为0.307.年龄别伤残权重为0.096～0.377,高于全球疾病负担研究中确定的0.005～0.006.伤残权重值随着年龄增长呈上升趋势,年龄组差异有统计学意义（x2=34.559,P＜ 0.01）.男、女性伤残权重分别为0.265和0.357,女性明显高于男性,差异具有统计学意义（Z=2.503,P＜ 0.05）.通径分析显示：对伤残权重有直接作用的变量按作用大小依次为年龄,患病年数,收入水平,性别、营养不良、消瘦,文化程度,贫血和记忆力下降;有间接作用的变量按作用大小依次为年龄、收入水平、患病年数和性别;总体影响前3位的分别为年龄、患病年数、收入水平. 结论 晚期血吸虫病患者每存活1年平均损失近3/10个健康寿命年.该评定结果高于全球疾病负担研究的确定值,初步反映了我国晚期血吸虫病患者的失能情况.     

Effect of (+)-methamphetamine on path integration learning,novel object recognition,and neurotoxicity in rats

RATIONALE: Methamphetamine (MA) has been implicated in cognitive deficits in humans after chronic use. Animal models of neurotoxic MA exposure reveal persistent damage to monoaminergic systems but few associated cognitive effects. OBJECTIVES: Since questions have been raised about the typical neurotoxic dosing regimen used in animals and whether it adequately models human cumulative drug exposure, these experiments examined two different dosing regimens. MATERIALS AND METHODS: Rats were treated with one of the two regimens: one based on the typical neurotoxic regimen (4 x 10 mg/kg every 2 h) and one based on pharmacokinetic modeling (Cho AK, Melega WP, Kuczenski R, Segal DS Synapse 39:161-166, 2001) designed to better represent accumulating plasma concentrations of MA as seen in human users (24 x 1.67 mg/kg once every 15 min) matched for total daily dose. In two separate experiments, dosing regimens were compared for their effects on markers of neurotoxicity or on behavior. RESULTS: On markers of neurotoxicity, MA showed decreased dopamine (DA) and 5-HT, increased glial fibrillary acidic protein, and increased corticosterone levels regardless of dosing regimen 3 days post-treatment. Behaviorally, MA-treated groups, regardless of dosing regimen, showed hypoactivity, increased initial hyperactivity to a subsequent MA challenge, impaired novel object recognition, impaired learning in a multiple T water maze test of path integration, and no differences on spatial navigation or reference memory in the Morris water maze. After behavioral testing, reductions of DA and 5-HT remained. CONCLUSIONS: MA treatment induces an effect on path integration learning not previously reported. Dosing regimen had no differential effects on behavior or neurotoxicity.     

Socioecological Path Analytic Model of Diet Quality among Residents in Two Urban Food Deserts

BackgroundDiet is critical to chronic disease prevention, yet there are persistent disparities in diet quality among Americans. The socioecological model suggests multiple factors, operating at multiple levels, influence diet quality.ObjectiveThe goal was to model direct and indirect relationships among healthy eating identity, perceived control of healthy eating, social support for healthy eating, food retail choice block scores, perceptions of healthy food availability, and food shopping behaviors and diet quality measured using Healthy Eating Index-2010 scores (HEI-2010) for residents living in two urban communities defined as food deserts.DesignA cross-sectional design was used including data collected via self-reported surveys, 24-dietary recalls, and through objective observations of food retail environments.Participants/settingData collection occurred in 2015-2016 in two low-income communities in Cleveland (n=243) and Columbus (n=244), OH.Main outcome measureHEI-2010 scores were calculated based on the average of three 24-hour dietary recalls using the Nutrition Data System for Research.AnalysisSeparate path models, controlled for income, were run for each community. Analysis was guided by a conceptual model with 15 hypothesized direct and indirect effects on HEI-2010 scores. Associations were considered statistically significant at P<0.05 and P<0.10 because of modest sample sizes in each community.ResultsAcross both models, significant direct effects on HEI-2010 scores included healthy eating identity (β=.295, Cleveland; β=.297, Columbus, P<0.05) and distance traveled to primary food store (β=.111, Cleveland, P<0.10; β=.175, Columbus, P<0.05). Perceptions of healthy food availability had a significant, inverse effect in the Columbus model (β=−.125, P<0.05). The models explained greater variance in HEI-2010 scores for the Columbus community compared with Cleveland (R²=.282 and R²=.152, respectively).ConclusionsFindings highlight the need for tailored dietary intervention approaches even within demographically comparable communities. Interventions aimed at improving diet quality among residents living in food deserts may need to focus on enhancing healthy eating identity using culturally relevant approaches while at the same time addressing the need for transportation supports to access healthy food retailers located farther away.     

原伊鲁烷型倍半萜化合物研究进展

从真菌资源分布和化合物基本骨架,波谱特征,药理活性及生源途径等方面,综述了国内外报道的52个原伊鲁烷型化合物。为该类化合物的研究开发提供参考。     

医学生人格特质、应对方式及心理健康状况的通径分析

目的:探讨人格特质及应对方式对医学生心理健康的影响.方法:采用分层整群抽样法对潍坊医学院486名医学生进行艾森克人格问卷简式量表(EPQ-RSC)、简易应对方式问卷(SCSQ)及一般健康问卷(GHQ-20)调查研究,采用通径分析研究影响医学生心理健康的主要因素及其作用方式.结果:研究显示,外向型和神经质人格是医学生自我...     

Importance of Path Planning Variability: A Simulation Study

Individuals vary in the way they navigate through space. Some take novel shortcuts, while others rely on known routes to find their way around. We wondered how and why there is so much variation in the population. To address this, we first compared the trajectories of 368 human subjects navigating a virtual maze with simulated trajectories. The simulated trajectories were generated by strategy-based path planning algorithms from robotics. Based on the similarities between human trajectories and different strategy-based simulated trajectories, we found that there is a variation in the type of strategy individuals apply to navigate space, as well as variation within individuals on a trial-by-trial basis. Moreover, we observed variation within a trial when subjects occasionally switched the navigation strategies halfway through a trajectory. In these cases, subjects started with a route strategy, in which they followed a familiar path, and then switched to a survey strategy, in which they took shortcuts by considering the layout of the environment. Then we simulated a second set of trajectories using five different but comparable artificial maps. These trajectories produced the similar pattern of strategy variation within and between trials. Furthermore, we varied the relative cost, that is, the assumed mental effort or required timesteps to choose a learned route over alternative paths. When the learned route was relatively costly, the simulated agents tended to take shortcuts. Conversely, when the learned route was less costly, the simulated agents showed preference toward a route strategy. We suggest that cost or assumed mental effort may be the reason why in previous studies, subjects used survey knowledge when instructed to take the shortest path. We suggest that this variation we observe in humans may be beneficial for robotic swarms or collections of autonomous agents during information gathering.