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81.
Reports an error in What matters in implicit task sequence learning: Perceptual stimulus features, task sets, or correlated streams of information by Brigitte Weiermann, Josephine Cock and Beat Meier (Journal of Experimental Psychology: Learning, Memory, and Cognition, 2010[Nov], Vol 36[6], 1492-1509). Two figures appearing on pages 1500 and 1502 contained incorrect labels for the x-axis of the control condition (ranran). The correct versions of Figure 3 and Figure 4 are provided in the erratum. (The following abstract of the original article appeared in record 2010-22281-001.) Implicit task sequence learning may be attributed to learning the order of perceptual stimulus features associated with the task sequence, learning a series of automatic task set activations, or learning an integrated sequence that derives from 2 correlated streams of information. In the present study, our purpose was to distinguish among these 3 possibilities. In 4 separate experiments, we replicated and extended a previous study by Heuer, Schmidtke, and Kleinsorge (2001). The presence or absence of a sequence of tasks, as well as that of a sequence of different task-to-response mappings, was manipulated independently within experiments. Evidence of implicit sequence learning was found only when correlated sequences of tasks and mappings were present. No sequence learning effects were found when only a single task sequence or a single mapping sequence was present, even when the structure of the single sequence was identical to the structure of the integrated sequence of task-mapping combinations. These results suggest that implicit task sequence learning is not dependent on either perceptual learning of stimulus features or automatic task-set activation per se. Rather, it appears to be driven by correlated streams of information. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
82.
Cannabis use adversely affects adolescents and interventions that are attractive to adolescents are needed. This trial compared the effects of a brief motivational intervention for cannabis use with a brief educational feedback control and a no-assessment control. Participants were randomized into one of three treatment conditions: Motivational Enhancement Therapy (MET), Educational Feedback Control (EFC), or Delayed Feedback Control (DFC). Those who were assigned to MET and EFC were administered a computerized baseline assessment immediately following randomization and completed assessments at the 3- and 12-month follow-up periods. Participants in the DFC condition were not assessed until the 3-month follow-up. Following the completion of treatment sessions, all participants were offered up to four optional individual treatment sessions aimed at cessation of cannabis use. The research was conducted in high schools in Seattle, Washington. The participant s included 310 self-referred adolescents who smoked cannabis regularly. The main outcome measures included days of cannabis use, associated negative consequences, and engagement in additional treatment. At the 3-month follow-up, participants in both the MET and EFC conditions reported significantly fewer days of cannabis use and negative consequences compared to those in the DFC. The frequency of cannabis use was less in MET relative to EFC at 3 months, but it did not translate to differences in negative consequences. Reductions in use and problems were sustained at 12 months, but there were no differences between MET and EFC interventions. Engagement in additional treatment was minimal and did not differ by condition. Brief interventions can attract adolescent cannabis users and have positive impacts on them, but the mechanisms of the effects are yet to be identified. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
83.
Leon Cmielewski and Josephine Starrs' Seeker is a large-scale, interactive, data-mapping installation that explores the political themes of diaspora and displacement. It uses Flash to weave together a range of data, including spectators' family information, in an immersive environment. In this article, the authors place the work within the context of cinematic and design aesthetics.  相似文献   
84.
Films found on the windows of residential buildings have been studied. The main aim of the paper was to assess the roles of the films in the accumulation of potentially toxic chemicals in residential buildings. Thus the elemental and polycyclic aromatic hydrocarbon compositions of the surface films from the glass windows of eighteen residential buildings were examined. The presence of sample amounts of inorganic elements (4.0–1.2 × 106 μg m−2) and polycyclic aromatic hydrocarbons in the films (BDL - 620.1 ng m−2) has implications for human exposure and the fate of pollutants in the urban environment. To facilitate the interpretation of the results, data matrices consisting of the chemical composition of the films and the building characteristics were subjected to multivariate data analysis methods, and these revealed that the accumulation of the chemicals was strongly dependent on building characteristics such as the type of glass used for the window, the distance from a major road, age of the building, distance from an industrial activity, number of smokers in the building and frequency of cooking in the buildings. Thus, building characteristics which minimize the accumulation of pollutants on the surface films need to be encouraged.  相似文献   
85.
The properties of a blend containing a crystallizable component depend largely on the extent of crystallinity and the crystallization behavior of that component in presence of the other. Here, the semi crystalline high density polyethylene (HDPE) is blended with the amorphous elastomer, acrylonitrile butadiene rubber (nitrile rubber or NBR) and we focus mainly on the crystallinity of HDPE/NBR immiscible blends and its variation in the presence of compatibilizer and filler. The effect of blend ratio, compatibilizer concentration, dynamic vulcanization, and filler incorporation were carefully evaluated from the crystallinity measurements using differential scanning calorimeter and the basic aim of this work lies in tuning these conditions. This study allows the elucidation of the influence of crosslink density in regulating the crystallinity of thermoplastic elastomer blends. The scanning electron micrographs provide blend morphology from which the reduced domain size and the influence of NBR particles as heterogeneous nuclei for crystallization are evidenced especially at 5% compatibilizer concentration. The crystallinity of blends was observed to be high at 30 phr carbon black filler addition. Finally, the thermal stability of blends and their composites are also addressed and correlated with the crystallization effect. POLYM. ENG. SCI., 55:1203–1210, 2015. © 2014 Society of Plastics Engineers  相似文献   
86.
There is a growing need to understand how climate change impacts not only on people's livelihoods but also on the level and cost of local government infrastructure required to provide basic commodities such as water and energy. In South Africa, few studies have examined the impact of climate change on operations of local governments. This paper examines the impact of rainfall variability on municipalities’ water and energy demand. A non‐linear relationship between water and energy demand and rainfall variability was found. The results suggest that, by influencing the operations and budgets of local governments, climate change is a real threat to local governments. The local governments need to be proactively involved in the efforts to adapt to and mitigate climate change. This is particularly important in developing countries where the impact of climate change is more severe than in developed countries, yet adaptation and mitigation capabilities in these countries are weak.  相似文献   
87.
Public perceptions of crime as the most important problem (MIP) facing the country jumped tenfold, from 5% in March of 1992 to an unprecedented 52% in August of 1994. This study analyzed the effects of three network television news predictor variables and two FBI predictor variables to determine what statistically accounted for this "big scare". Based upon data from 1978 through 1998, results suggest that the 1994 "big scare" was more a network TV news scare than a scare based upon the real world of crime. The television news variables alone accounted for almost four times more variance in public perceptions of crime as the MIP than did actual crime rates.  相似文献   
88.
Multilevel models are increasingly used to estimate models for hierarchical and repeated measures data. The authors discuss a model in which there is mediation at the lower level and the mediational links vary randomly across upper level units. One repeated measures example is a case in which a person's daily stressors affect his or her coping efforts, which affect his or her mood, and both links vary randomly across persons. Where there is mediation at the lower level and the mediational links vary randomly across upper level units, the formulas for the indirect effect and its standard error must be modified to include the covariance between the random effects. Because no standard method can estimate such a model, the authors developed an ad hoc method that is illustrated with real and simulated data. Limitations of this method and characteristics of an ideal method are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
The epithelial cell tight junction structure is the site of the transepithelial movement of solutes and water between epithelial cells (paracellular permeability). Paracellular permeability can be divided into two distinct pathways, the Pore Pathway mediating the movement of small ions and solutes and the Leak Pathway mediating the movement of large solutes. Claudin proteins form the basic paracellular permeability barrier and mediate the movement of small ions and solutes via the Pore Pathway. The Leak Pathway remains less understood. Several proteins have been implicated in mediating the Leak Pathway, including occludin, ZO proteins, tricellulin, and actin filaments, but the proteins comprising the Leak Pathway remain unresolved. Many aspects of the Leak Pathway, such as its molecular mechanism, its properties, and its regulation, remain controversial. In this review, we provide a historical background to the evolution of the Leak Pathway concept from the initial examinations of paracellular permeability. We then discuss current information about the properties of the Leak Pathway and present current theories for the Leak Pathway. Finally, we discuss some recent research suggesting a possible molecular basis for the Leak Pathway.  相似文献   
90.
Abstract

This paper presents design, development, and testing of a resonant sensor to measure mass in the range of 0–10 grams. The main feature of the proposed sensor is the microcontroller based closed loop electronics. The advantage of using the microcontroller is that the method can be easily extended for any range of measurand.  相似文献   
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