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关键词： Schizophrenia   Homocysteine   Prevalence   Psychiatric symptoms   PANSS  

摘要： Previous studies have shown that high homocysteine worsens the occurrence, symptoms, and prognosis of patients with schizophrenia. The purpose of this study was to evaluate the prevalence, clinical correlation, and demographic characteristics of hyperhomocysteinemia in Han Chinese schizophrenia patients. In this study, we enrolled 330 schizophrenia patients and 190 healthy controls. Positive and Negative Syndrome Scale (PANSS) was used to evaluate the psychiatric symptoms of patients with schizophrenia. The plasma homocysteine level was measured by the enzyme cycle method and the concentration of homocysteine > 15 mu mol/L was defined as hyperhomocysteinemia. The prevalence of hyperhomocysteinemia in Han Chinese schizophrenia patients and healthy controls was 55.05% and 26.98%, respectively. Schizophrenia patients with hyperhomocysteinemia had more male proportion, older age, higher smoking rate, lower HDL level, higher PANSS total score, and higher negative factor than those patients without hyperhomocysteinemia. Binary logical regression result showed that gender and age were the independent risk factors of hyperhomocysteinemia. Han Chinese patients with schizophrenia had high prevalence hyperhomocysteinemia than healthy controls, and elderly male patients have a higher risk of hyperhomocysteinemia. This study was registered in the China Clinical Trial Registration Center (chiCTR 1800017044).

ISBN: (纸本)9787030689597

关键词： age‐   and‐   stage model   age‐   from‐   stage model   generation time   matrix model   net reproductive rate   population growth rate   reproductive value   senescence   Silene spaldingii   stable age distribution   vital rates  

摘要： Life history theories analyze and predict variation in vital rates, such as survival and reproduction, based on age. The age-from-stage method to derive age-specific vital rates from stage data was developed because age-specific data are rarely obtained for plants. Age-specific vital rates derived by this method might underestimate effects of age on vital rates, because the models assume that vital rates do not vary within stage classes. Consequently, population models and life history summaries relying on these vital rates could be biased against detecting senescence. Here, we perform a comparative study of methods to estimate age-specific vital rates using monitoring data with known age and stage. We derived age-, stage-, and age-and-stage-specific vital rates with demographic data from a long-lived perennial, Silene spaldingii. Then, we derived three age-specific population matrix models (age, age-from-stage, and age-and-stage). For each model, we derived life history summaries commonly used in ecology: population growth rate, net reproductive value, relative reproductive values, stable age distribution, generation time, and sensitivity and elasticity of population growth rate. Many vital rates depended on both age and stage in S. spaldingii. However, this species does not senesce;in fact, the number of flowers increased with age. As expected, the age-from-stage method was not able to accurately recreate the age dependence in some life history summaries, such as relative reproductive value. The age-from-stage model suggested faster reproductive dynamics in S. spaldingii than the models based on known age, i.e., plants started to reproduce earlier, and fertility remained constant thereafter, which may lead to biased predictions about evolutionary consequences of age-dependent life history traits. However, population growth rate, generation time, and net reproductive rate did not differ significantly among the models. Our study demonstrated that some metrics are ro

关键词： 统计学  

ISBN: (纸本)9787030685704

摘要： 作为数据分析的有效工具,统计方法已广泛应用于社会科学和自然科学的各个领域.本书兼顾统计知识的全面性和统计课程的系统性,结合编者多年的教学实践经验和国内外优秀教材的成果,在内容上主要包括多元统计分析概述、主成分分析、聚类分析、判别分析、因子分析、时间序列模型引论、平稳时间序列模型、非平稳时间序列模型、结构方程模型.全书分9章叙述.另外,书中大部分统计方法都给出了用R语言实现的实际操作过程.

关键词： Kinematics   Sensors   Acceleration   Autonomous vehicles   Anomaly detection   Real-time systems   Statistical learning   Statistical learning   CACC   anomaly detection   kinematic model  

摘要： This paper focuses on Cooperative Adaptive Cruise Control (CACC) in autonomous vehicles. In CACC, vehicles regulate their speed according to a preceding "leader" vehicle in the lane, forming a platoon. In a benign environment, CACC reduces fuel consumption, maximizes road capacity, and ensures traffic safety. However, CACC is vulnerable to various security threats. In this paper, we consider one of the critical threats, where the platoon leader is compromised, and forges acceleration information sent to platoon members. Such attack would lead to traffic instability and potential collisions. First, we propose information sharing in CACC model to allow vehicles and fixed infrastructure to sense and share information about platoon leaders, hence improves the reliability and supports the detection of anomalous behavior. Then, we propose a real-time anomaly detection mechanism that combines statistical learning with the physics laws of kinematics. Specifically, we propose Generalized Extreme Studentized Deviate with Sliding Chunks (GESD-SC) approach, which is applied at each vehicle in the platoon to detect anomalies in real-time based on the vehicle's own speeding decisions. Kinematic model is also utilized to detect unexpected deviations using the leader's information, communicated directly and observed by the leader's neighboring vehicle(s) and/or supporting infrastructure. Combining kinematic model with GESD-SC has shown to be effective in detecting falsification attacks in CACC. Furthermore, we analyze the time performance, and show that the proposed technique outperforms existing method in detection accuracy and processing time.

关键词： 统计学   教材  

ISBN: (纸本)9787568298742

摘要： 本教材是在2018年北京理工大学出版社出版的《新编统计学》一书的基础上修订而成的。《新编统计学》第1版自出版发行以来受到同学和读者的广泛欢迎，作为教材或主要参考书先后多次重印。本次修订在保留了原书基本框架和内容体系的基础上，对各章体例进行了调整，将课后复习思考、实践技能训练、知识能力训练单独整理为配套电子教材，并增加微课视频，教师和学生通过扫描章节二维码就可以进入学习、练习和移动微课。此外，我们适时更新了教材数据和案例，将最新的统计数据引入教材，在教学资料等内容的时效性方面进行了更新和充实。在教材修订过程中力求做到科学性与实用性、先进性与针对性相统一。在正确阐述统计学原理的同时，着重于基本概念、基础方法的阐述，注重学生动手能力的培养。力求体现强基础、重应用和当前进行的素质教育和创新教育的教育目标。全书共9章，第1章主要涉及统计基本概念；第2—3章主要涉及统计基础方法；第4—8章主要介绍统计分析技能及应用；第9章主要介绍Excel在统计中的应用。

关键词： 算术平均数   统计学符号   t检验   中位数   标准差   小写   国家标准   书写  

摘要： 根据国家标准BG3358-82《统计学名词及符号》的有关规定,请作者书写统计学符号时注意:①样本的算术平均数用英文小写xˉ,不用大写Xˉ,也不用Mean或M(中位数仍用M);②标准差用英文小写s,不用SD;③标准误用英文小写s xˉ,不用SE;④t检验用英文小写t。

关键词： 简单化处理   单因素方差分析   盲目套用   定量资料   回归分析   散布图   定性资料   具备的条件  

摘要： 统计学分析方法的选择:对于定量资料,应根据所采用的设计类型、资料所具备的条件和分析目的,选用合适的统计学分析方法,不应盲目套用t检验和单因素方差分析;对于定性资料,应根据所采用的设计类型、定性变量的性质和频数所具备的条件以及分析目的,选用合适的统计学分析方法,不应盲目套用χ2检验。对于回归分析,应结合专业知识和散布图,选用合适的回归类型,不应盲目套用简单直线回归分析,对具有重复实验数据的回归分析资料,不应简单化处理.