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11.
This study explores factors influencing international students' likelihood of using the Internet to seek disaster-related information should a disaster affect their countries. A cross-sectional survey was conducted in two universities in America between August 1 and September 30, 2005. Two hundred twenty-nine (n = 229) students completed the self-administered questionnaires. ANOVA analyses found that respondents' Internet self-efficacy had no significant impact on their intentions to seek disaster-related information on the Internet. However, respondents' Internet dependency and attitude toward seeking information online were found to have a significant effect on such intentions.  相似文献   
12.
Norman JF  Dawson TE  Butler AK 《Perception》2000,29(11):1335-1359
The ability of younger and older adults to perceive the 3-D shape, depth, and curvature of smooth surfaces defined by differential motion and binocular disparity was evaluated in six experiments. The number of points defining the surfaces and their spatial and temporal correspondences were manipulated. For stereoscopic sinusoidal surfaces, the spatial frequency of the corrugations was also varied. For surfaces defined by motion, the lifetimes of the individual points in the patterns were varied, and comparisons were made between the perception of surfaces defined by points and that of more ecologically valid textured surfaces. In all experiments, the older observers were less sensitive to the depths and curvatures of the surfaces, although the deficits were much larger for motion-defined surfaces. The results demonstrate that older adults can extract depth and shape from optical patterns containing only differential motion or binocular disparity, but these abilities are often manifested at reduced levels of performance.  相似文献   
13.

Purpose

This paper advances a socioecological perspective toward understanding the relationship between demography and job attitudes by considering the joint effects of individual ethnicity and ethnic group relative representation—the degree to which an individual’s own demographic group is represented similarly in their organization and the community in which the organization is located.

Design/Methodology/Approach

Hierarchical polynomial regression analyses of census and survey data from 57,000 employees of 142 hospitals in the United Kingdom suggest that ethnic group relative representation is related to ethnic minority employees’ job satisfaction and turnover intentions.

Findings

An asymmetric pattern emerged wherein the effect of under-representation on turnover intentions was stronger than the effect of over-representation. Moreover, the effects of relative representation varied with respectful treatment by coworkers; relative representation had little effect on attitudes of employees who reported low levels of coworker respect but generally enhanced attitudes when respect was high.

Originality/Value

This work points to the meaningful role that socioecological factors can play in what are typically considered to be intraorganizational phenomena, thereby highlighting the need for organizational research to assess relevant aspects of the communities in which organizations are embedded.
  相似文献   
14.
Background: Prevalence estimates of adults identifying as transgender are scarce, particularly in the United States. Method: The current study endeavored to estimate the prevalence of individuals identifying as transgender in a large online sample of adult U.S. residents (n = 6,727) and compare the prevalence of common mental health disorders (depression, anxiety, attention-deficit/hyperactivity disorder) and the age of onset for individuals identifying as men or women versus those identifying as transgender. Results: The prevalence estimate of individuals identifying as transgender was 0.8%. Individuals identifying as transgender were significantly more likely than individuals identifying as men or women to report having had a single diagnosis or co-occurring diagnoses for all three disorders examined. Additionally, transgender individuals were more likely than individuals identifying as men or women to receive a diagnosis of anxiety or depression at a younger age. Conclusion: Given the prevalence of transgender individuals and the associations with common mental health conditions, clinicians must be informed and competent to care for their clinical needs. This study introduces online crowdsourcing resources as a potentially fruitful option for reaching and researching gender diversity.  相似文献   
15.
Drugs modulating gamma-aminobutyric acid (GABA) transmission via the benzodiazepine (BZ) site on the gamma-aminobutyric acid type A (GABAA) receptor have been in widespread use for more than 40 years to treat anxiety, epilepsy, and sleep disorders. These drugs have been shown to be safe, well tolerated, and effective although the mechanism by they produce a myriad of pharmacologic effects remains elusive. In recent years it has been discovered that, although the GABAA receptor is widely distributed in the brain, the substructure and composition of the receptor differs from between brain regions. Termed "GABAA receptor subtypes" their discovery leads to speculation that different subtypes may mediate specific effects of BZs such as anxiety or sedation. The phenotypic analysis of transgenic knock-in and knock-out mice in which particular GABAA receptors were rendered insensitive to the effects of BZ while others were unaffected confirmed this speculation. Subsequently, subtype-specific GABAA ligands were developed that, for example, retained the anxiolytic effects of BZs but were devoid of their sedative effects. Therefore, it may be possible to develop effective anxiolytic compounds that have a much reduced side-effect profile compared with existing drugs.  相似文献   
16.
17.
In the first study, rats were trained to pull a chain on a schedule (RPI) that regulates the probability of reinforcement to maintain a constant average reinforcement rate without differentially reinforcing long inter-response times (IRTs). Although the response rate was sensitive to the overall rate of reinforcement, performance was unaffected by variations between 1 and 50 in the IRT memory size used in programming the schedule. In the second study, two groups of animals performed on either a random-interval (RI) schedule or a RPI schedule, with reinforcement rates determined by those generated by a third group performing on a random ratio (RR) 20 schedule. The RI group responded at a lower rate than the RPI group, which, in turn, responded at a lower rate than the RR group, even though the three groups experienced comparable rates of reinforcement. The fact that the RPI group responded at a lower rate than the RR group suggests that the standard response rate difference observed between ratio and interval schedules, which have been matched for reinforcement rate, cannot be attributed solely to the fact that conventional interval schedules differentially reinforce long IRTs.  相似文献   
18.
In two experiments, rats observed a conspecific demonstrator pushing a single manipulandum, a joystick, to the right or to the left for food reward before being given access to the joystick, for the first time, from a different orientation. In Experiment 1, rats that had observed left-pushing made more of their first three responses to the left than did rats that had observed right-pushing. In Experiment 2 the axis of joystick movement was rotated through 90° between observation and testing for half of the animals. These rats, like those that were tested with the joystick in the position it had occupied during demonstrator responding, showed a significant tendency to push the joystick in the same direction relative to their own bodies as had their demonstrators. These results, which cannot be explained in terms of stimulus-reinforcer learning, provide evidence that rats are capable of imitation, i.e. response, or response-reinforcer, learning by observation.  相似文献   
19.
Magazine-trained observer rats confronted a conspecific demonstrator pushing a joystick to the right or to the left for food reward before the observers were given access to the joystick from the position previously occupied by the demonstrator and rewarded for responses in both directions. For half of the observers (group 0), the joystick was in the same position when acted upon by demonstrators and observers; for the other half (group 180) the manipulandum was rotated 180 within its mounting between observation and test. As in previous experiments using this bidirectional control procedure, rats in group 0 showed demonstratorconsistent responding-that is, they pushed the joystick in the same direction, relative to the actor's body, as had their demonstrators. However, group 180 showed a reverse effect: reliable demonstrator-inconsistent responding. These results suggest that attractive odour or taste cues deposited by demonstrators on the side of the joystick contralateral to the direction of responding are sufficient to produce demonstrator-consistent responding in the bidirectional control procedure.  相似文献   
20.
Many studies have examined how humans and other animals reestablish a sense of direction following disorientation in enclosed environments. Results showing that geometric shape of an enclosure is typically encoded, sometimes to the exclusion of featural cues, have led to suggestions that geometry might be encoded in a dedicated geometric module. Recently, Miller and Shettleworth (2007) proposed that the reorientation task be viewed as an operant task and they presented an associative operant model that appears to account for many empirical findings from reorientation studies. In this paper we show that, although Miller and Shettleworth's insights into the operant nature of the reorientation task may be sound, their mathematical model has a serious flaw. We present simulations to illustrate the implications of the flaw. We also propose that the output of a simple neural network, the perceptron, can be used to conduct operant learning within the reorientation task and can solve the problem in Miller and Shettleworth's model.  相似文献   
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