Intraindividual Variability May Not Always Indicate Vulnerability in Elders' Cognitive Performance.

This study examined consistency of performance, or intraindividual variability, in older adults' performance on 3 measures of cognitive functioning: inductive reasoning, memory, and perceptual speed. Theoretical speculation has suggested that such intraindividual variability may signal underlying vulnerability or neurologic compromise. Thirty-six participants aged 60 and older completed self-administered cognitive assessments twice a day for 60 consecutive days. Intraindividual variability was not strongly correlated among the 3 cognitive measures, but, over the course of the study, intraindividual variability was strongly intercorrelated within a task. Higher average performance on a measure was associated with greater performance variability, and follow-up analyses revealed that a higher level of intraindividual variability is positively associated with the magnitude of a person's practice-related gain on a particular measure. The authors argue that both adaptive (practice-related) and maladaptive (inconsistency-related) intraindividual variability may exist within the same individuals over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

~(137)Cs辐照小麦干种子M_1代的辐射效应和细胞学分析

~(60)Co-γ射线辐照小麦干种子对M_1代的生物学和细胞学效应产生影响,这方面已有报道,而铯-137的辐射效应报道较少。本试验利用我所的铯-137和钴-60源不同剂量照射小麦干种子,比较M_1代的生物学及细胞学效应,为育种提供依据。     

Small Classes in the Early Grades, Academic Achievement, and Graduating From High School.

This investigation addressed 3 questions about the long-term effects of early school experiences: (a) Is participation in small classes in the early grades (K-3) related to high school graduation? (b) Is academic achievement in K-3 related to high school graduation? (c) If class size is related to graduation, is the relationship explained by the effect of participation in small classes on students' academic achievement? The study included 4,948 participants in Tennessee's class-size experiment, Project STAR. Analyses showed that graduating was related to K-3 achievement and that attending small classes for 3 or more years increased the likelihood of graduating from high school, especially among students eligible for free lunch. Policy and research implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Subjective and Reinforcing Effects of Smoking During Negative Mood Induction.

Two notions strongly held by many smokers are that negative mood increases smoking behavior and that this increase is due to the ability of smoking to alleviate negative affect. This study used a modified mood induction procedure to examine both the impact of smoking on induced mood, as well as the effect of induced mood on actual smoking behavior. Forty-eight smokers were randomly assigned to a smoking or a water-drinking comparison group. Each participant attended 3 sessions during which 1 of 3 mood states (positive, negative, or neutral) was induced. Contrary to expectation, smoking did not attenuate negative affect. However, negative mood induction subsequently quickened latency to smoke and increased number of puffs consumed ad lib. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Substituent effects on the reduction potentials of benzalacetophenones (chalcones): Improved substituent constants for such correlations

The reduction potentials of a set of 23 monosubstituted and 7 disubstituted benzalacetophenones (chalcones) are linearly correlated considerably better with the σⁿ values of van Bekkum, Verkade, and Wepster than with Hammett σ. Groups were found to exert the same effect upon the reduction potential irrespective of which ring they are located on. The data for monosubstituted benzalacetophenones can be used to predict the reduction potentials of disubstituted derivatives with good accuracy.     

Electrochemical preparation and redox/ion exchange properties of polypyrrole in aqueous sodium hexafluoroaluminate

Electrodeposition and redox switching performance of polypyrrole in aqueous solution of sodium hexafluoroaluminate are described. An incorporation of NaAlF₆²⁻ into the polymer phase is indicated by the EQCM analysis of electrodeposition. A SEM micrograph shows a characteristic morphology of the polymer layer. A mechanism of the redox process of polypyrrole is discussed based on CV and EQCM results involving the measurements performed as a function of a time scale of the redox cycle and a life time of the electrode. Structure determining interactions between polymer sites and counterions are indicated. Participations of ion-pair counterion, co-ion, salt, water, oxygen in the redox process of polypyrrole are discussed. A slow irreversible rearrangement in the structure/composition, inducing a change in the mechanism of the reversible redox process, is postulated to occur during the reduction process of the virgin anion-exchanging polypyrrole. Long time scale processes were observed to result in cation exchange properties accompanied by a substantial decrease in redox activity and/or CV currents of the polypyrrole electrode. The performance of the primary hexafluoroaluminate counterion electrode, prepared in aqueous solution of sodium hexafluoroaluminate, is compared to the secondary hexafluoroaluminate counterion electrode, prepared in a presence of the sodium chloride solution. In general, the CV and EQCM characteristics of the two system are similar due to pronounced contribution of the bathing electrolyte to the performance of the polymer electrode.     

Conditioning following repeated exposure to MDMA in rats: Role in the maintenance of MDMA self-administration.

There has been some controversy in the literature concerning the ability of ±3,4 methylenedioxymethamphetamine (MDMA) to reinforce operant responding in rats. In the present study, operant responding maintained by intravenous MDMA infusions increased when the fixed ratio schedule was increased from 1 to 5, decreased when saline was substituted for MDMA, and increased again when MDMA was reintroduced. During self-administration training, each infusion of MDMA was paired with the illumination of a light stimulus. The role of the continued presentation of this drug-associated stimulus in operant responding was measured in groups of rats that had received comparable exposure (average 19 daily test sessions) to MDMA during training. When either the light stimulus or the drug infusion was omitted, operant responding decreased gradually over the 15-day test period following training. When both the light stimulus and the MDMA infusion were omitted, there was a dramatic decrease in operant responding that persisted for the entire 15-day test period. These findings suggest that cues associated with MDMA develop conditioned properties that might contribute to drug taking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling heterogeneity in social interaction processes using multilevel survival analysis.

More than 15 years ago, survival or hazard regression analyses were introduced to psychology (W. Gardner & W. A. Griffin, 1989; W. A. Griffin & W. Gardner, 1989) as powerful methodological tools for studying real time social interaction processes among dyads. Almost no additional published applications have appeared, although such data are commonly collected and the applicable questions are central to many important theoretical perspectives. To revisit the basic methods, the authors use an example from emotion regulation theory in which the level of child antisocial behavior is hypothesized to be positively associated with the hazard rate of angry emotions and negatively associated with sad, fearful emotions in the face of parental negative behavior (scolding). The authors discuss the limitations of traditional approaches to the analysis of social interaction and demonstrate improvements in the ability to model individual differences now available in existing software. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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文章介绍了标准气在天然气分析测试中的作用和国外的发展动向，管输天然气质量指标，我国天然气气质标准和天然气分析测度用标准气的量质传递系统。对发展我国天然气分析测试用标准气提出了几点看法：①尽快建立我国的可溯源至其准的标准气量值递系统；②进一步形对分压不的研究；③开展标准气与国际通用标准气的互换性试验和重现标准气制备技术的发展。