祛病延年的良药--幽默

当今世界不少国家在紧张的劳作之余,创办各种新奇的幽默组织,借以消除疲劳,松弛情绪,增进健康。幽默杂志美国健康学家创办的幽默杂志《疯狂》被西欧一些国家读者评为世界最佳幽默杂志。被它挖苦过的社会时弊,常常成为美国公民口中流传的笑柄。勤奋的美国人在操劳之余,从《疯狂》     

用于项目生成的认知模型的构建与比较——以矩阵完成问题为例

项目生成是一种新的测验编制技术,它可以弥补传统测验编制技术的缺陷.使用该技术编制测验,要进行大量的前期工作,如必须要了解和归纳所编测验中项目的所有刺激特征,据此建立认知模型,再将认知模型与心理计量模型联合,构建能预测新生成项目难度的数学模型等.该研究以矩阵完成问题为例,在带约束的两参数Logistic模型的基础上,通过对构建的几个认知模型的比较,挑选合适的认知模型为矩阵完成问题的项目生成研究服务.研究结果表明,自建的认知模型能够满足矩阵问题项目生成的要求.     

Cyclophosphamide impairs hippocampus-dependent learning and memory in adult mice: Possible involvement of hippocampal neurogenesis in chemotherapy-induced memory deficits

Cyclophosphamide (CYP) is an anti-neoplastic agent as well as an immunosuppressive agent. In order to elucidate the alteration in adult hippocampal function following acute CYP treatment, hippocampus-related behavioral dysfunction and changes in adult hippocampal neurogenesis in CYP-treated (intraperitoneally, 40 mg/kg) mice (8–10-week-old ICR) were analyzed using hippocampus-dependent learning and memory tasks (passive avoidance and object recognition memory test) and immunohistochemical markers of neurogenesis (Ki-67 and doublecortin (DCX)). Compared to the vehicle-treated controls, mice trained at 12 h after CYP injection showed significant memory deficits in passive avoidance and the object recognition memory test. The number of Ki-67- and DCX-positive cells began to decrease significantly at 12 h post-injection, reaching the lowest level at 24 h after CYP injection; however, this reverted gradually to the vehicle-treated control level between 2 and 10 days. We suggest that the administration of a chemotherapeutic agent in adult mice interrupts hippocampal functions, including learning and memory, possibly through the suppression of hippocampal neurogenesis.     

提示线索、目标信息对大学生攻击可能性判断的影响

该研究探讨了在受挫情境中,不同的提示线索和目标信息对大学生攻击可能性判断的影响,结果发现:1)线索提示对大学生攻击可能性判断存在显著性影响,而目标信息的主效应、目标信息与提示线索的交互作用并不显著。2)与图片线索相比较,命题线索更容易激活攻击性认知,进而影响大学生对攻击可能性的判断。     

The Effect of Ad Skepticism and Celebrity Preference on Brand Attitude Change in Celebrity-Endorsed Advertising

The use of a celebrity endorser who is well recognized and favorably evaluated by the target viewers is a common strategy used by advertisers to increase the persuasiveness of an advertisement. Yet, at the same time, being skeptical of the claim being made by the celebrity endorser is the typical response of the viewers to such persuasion attempts. The present research examines how these effects potentially counterbalance each other as viewers evaluate the advertised brand in a low-involvement setting. The results show that the degree of ad skepticism and the relative allocation of attentional resources to celebrity and brand elements in advertisements determine how preference for a celebrity endorser is transferred to the advertised brand. The findings provide a more complete understanding of the psychological mechanisms by which celebrity preference influences brand attitude change than has previously been available. They indicate that ad skepticism may be the missing link in understanding the effectiveness of celebrity-endorsed advertising.     

Correlating the internal length in strain gradient plasticity theory with the microstructure of material

The internal length is the governing parameter in strain gradient theories which among other things have been used successfully to interpret size effects at the microscale. Physically, the internal length is supposed to be related with the microstructure of the material and evolves during the deformation. Based on Taylor hardening law, we propose a power-law relationship to describe the evolution of the variable internal length with strain. Then, the classical Fleck–Hutchinson strain gradient theory is extended with a strain-dependent internal length, and the generalized Fleck–Hutchinson theory is confirmed here, by comparing our model predictions to recent experimental data on tension and torsion of thin wires with varying diameter and grain size. Our work suggests that the internal length is a configuration-dependent parameter, closely related to dislocation characteristics and grain size, as well as sample geometry when this affects either the underlying microstructure or the ductility of the material.     

Sex differences in adolescent ethanol drinking to behavioral intoxication

Rodent models have been especially useful for investigating adolescent ethanol exposure. However, there is a paucity of studies examining sex differences in behavioral intoxication from adolescent ethanol drinking. Here, we used an ethanol drinking model to investigate if adolescent rats of both sexes readily drink ethanol to measurable behavioral intoxication, indicated by increased impulsive action and motor incoordination. Beginning on postnatal day (P) 28, male and female Long‐Evans rats were given 30‐min access to a solution of sucrose (20%) or sweetened ethanol (20% sucrose +15% ethanol) every other day until P60 and once after 2 weeks of forced abstinence (on P75). On alternate (nondrinking) days, rats were reinforced with a food pellet for making a cued nosepoke response. Beginning on P56, rats were tested in this task after drinking sessions to assess ethanol‐induced changes in impulsive action, defined as premature responding prior to cue presentation. Motor coordination was assessed before and after drinking sessions using an incline plane test. Adolescent male and female rats readily consumed ethanol to behavioral intoxication, measured as reduced motor coordination. Following forced abstinence, females displayed greater ethanol‐induced impulsive action. These studies provide evidence for sex differences in behavioral intoxication following adolescent ethanol drinking.     

Bayesian Diagnostics of Hidden Markov Structural Equation Models with Missing Data

Cocaine is a type of drug that functions to increase the availability of the neurotransmitter dopamine in the brain. However, cocaine dependence or abuse is highly related to an increased risk of psychiatric disorders and deficits in cognitive performance, attention, and decision-making abilities. Given the chronic and persistent features of drug addiction, the progression of abstaining from cocaine often evolves across several states, such as addiction to, moderate dependence on, and swearing off cocaine. Hidden Markov models (HMMs) are well suited to the characterization of longitudinal data in terms of a set of unobservable states, and have increasingly been used to uncover the dynamic heterogeneity in progressive diseases or activities. However, the existence of outliers or influential points may misidentify the hidden states and distort the associated inference. In this study, we develop a Bayesian local influence procedure for HMMs with latent variables in the presence of missing data. The proposed model enables us to investigate the dynamic heterogeneity of multivariate longitudinal data, reveal how the interrelationships among latent variables change from one state to another, and simultaneously conduct statistical diagnosis for the given data, model assumptions, and prior inputs. We apply the proposed procedure to analyze a dataset collected by the UCLA center for advancing longitudinal drug abuse research. Several outliers or influential points that seriously influence estimation results are identified and removed. The proposed procedure also discovers the effects of treatment and individuals’ psychological problems on cocaine use behavior and delineates their dynamic changes across the cocaine-addiction states.     

Young children discover how to deceive in 10 days: a microgenetic study

We investigated how the ability to deceive emerges in early childhood among a sample of young preschoolers (Mean age = 34.7 months). We did this via a 10‐session microgenetic method that took place over a 10‐day period. In each session, children played a zero‐sum game against an adult to win treats. In the game, children hid the treats and had opportunities (10 trials) to win them by providing deceptive information about their whereabouts to the adult. Although children initially showed little or no ability to deceive, most spontaneously discovered deception and systematically used it to win the game by the tenth day. Both theory of mind and executive function skills were predictive of relatively faster patterns of discovery. These results are the first to provide evidence for the importance of cognitive skills and social experience in the discovery of deception over time in early childhood.