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21.
A considerable amount of empirical research has been conducted on ways to improve the eyewitness identification process, with emphasis on the use of lineups. Public policy changes are currently underway with respect to lineup procedures: Sequential lineups are being recommended to police as the best practice. This may be premature because the conditions under which sequential lineups are superior to simultaneous lineups are not well understood given the current literature: Many studies are reported with insufficient detail needed to judge the adequacy of the research design, new data show that the sequential superiority effect may vary as a function of study methodology, theoretical assumptions have not been adequately tested, and important comparisons that may rule out the ostensible superiority of the sequential lineup have not been studied. This review summarizes the literature, presents new data, and identifies the need for further empirical work before appropriately grounded recommendations as to the superiority of sequential lineups can be made. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Listeria monocytogenes has been isolated from condensate-forming surfaces in food processing plants. The objective of this research was to observe the behavior of L. monocytogenes on condensate-covered stainless steel with a Pseudomonas putida biofilm. L. monocytogenes-containing biofilms, either with or without added chicken protein, were incubated in a high humidity chamber at 12 degrees C to allow formation of condensate. Samples were analyzed for attached and unattached L. monocytogenes and total plate count periodically for 35 days. Samples were also taken for microscopic observation of Listeria and bacterial extracellular polymeric substances (EPS). L. monocytogenes attached in significantly greater numbers (> 3-log difference) to surfaces with preexisting P. putida biofilms than to Pseudomonas-free surfaces. L. monocytogenes survived in the presence or absence of P. putida with no added nutrients for 35 days, with numbers of survivors in the range of 3 to 4 log CFU/cm2 in the presence of P. putida and less than 2.9 log CFU/cm2 in pure culture. Attached and unattached L. monocytogenes were at similar levels throughout the incubation under all conditions studied. The addition of protein to the biofilms allowed growth of L. monocytogenes in pure culture during the first 7 days of incubation. Numbers of L. monocytogenes were not affected by the presence of P. putida when protein was present. Unattached L. monocytogenes were at levels of 3.6 to 6.7 log CFU/cm2 on the protein-containing surfaces. Microscopic observation of the condensate-covered biofilms indicated that L. monocytogenes formed microcolonies embedded within an EPS matrix over a 28-day period. This research demonstrates that L. monocytogenes can survive on condensate-forming stainless steel in low and high nutrient conditions, with or without the presence of Pseudomonas biofilm. The Listeria can detach and, therefore, have the potential to contaminate product.  相似文献   
24.
Interventions designed to reduce heavy drinking among college students often contain suggestions for drinking control strategies. However, little is known about the relationship between the use of these strategies and alcohol consumption. The authors developed a measure of drinking control strategies and investigated its psychometric properties in a sample of 250 college drinkers. Strategies clustered into three factors: selective avoidance of heavy drinking activities and situations, strategies used while drinking, and alternatives to drinking. These three types of strategies were independently associated with alcohol use; however, the first and last types were negatively associated with alcohol consumption, whereas the second type was positively associated with alcohol use. The findings from this study suggest that the type of strategy recommended may be important when the goal is alcohol reduction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
Emotion researchers often categorize angry and fearful face stimuli as "negative" or "threatening". Perception of fear and anger, however, appears to be mediated by dissociable neural circuitries and often elicit distinguishable behavioral responses. The authors sought to elucidate whether viewing anger and fear expressions produce dissociable psychophysiological responses (i.e., the startle reflex). The results of two experiments using different facial stimulus sets (representing anger, fear, neutral, and happy) indicated that viewing anger was associated with a significantly heightened startle response (p  相似文献   
26.
Ambulatory biosensor assessment includes a diverse set of rapidly developing and increasingly technologically sophisticated strategies to acquire minimally disruptive measures of physiological and motor variables of persons in their natural environments. Numerous studies have measured cardiovascular variables, physical activity, and biochemicals such as cortisol in psychopathology and treatment research. The physiological concomitants of many behavior and medical disorders and the benefits of a multimethod assessment strategy provide strong rationales for clinical applications of ambulatory biosensor measurement. A number of psychometric dimensions of evaluation are important in clinical applications of biosensor measurement, including accuracy and validity, reliability and consistency, clinical utility, incremental validity and utility, sensitivity to change, generalizability, cost benefits, and the conditional nature of dimensions of biomeasure evaluation. The authors review ambulatory biosensor methods and make recommendations for use of the technology. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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A study was conducted to investigate the body movements of participants waiting to be interviewed in one of two conditions: preparing to answer questions truthfully or preparing to lie. The effects of increased self-awareness were also investigated, with half of the participants facing a mirror; the other half facing a blank wall. Analysis of covertly obtained video footage showed a significant interaction for the duration of hand/arm movements between deception level and self-awareness. Without a mirror, participants expecting to lie spent less time moving their hands than those expecting to tell the truth; the opposite was seen in the presence of a mirror. Participants expecting to lie also had higher levels of anxiety and thought that they were left waiting for less time than those expecting to tell the truth. These findings led to the identification of further research areas with the potential to support deception detection in security applications.  相似文献   
29.
对于有线电视运营商来说,为满足当今快速增长的语音和高速数据业务的需要.双向通信系统中的“上行”回传就显得尤为重要。最初的“广播”网中,回传通道只局限于对覆盖用户的状态监控和基本的机顶盒控制,随着时间的推进,情况逐步发生变化:先是受限机顶盒交互的QPSK调制,然后是DOCSIS 1.x的16QAM调制,再到DOCSIS2.0和DOCSIS3.0的64QAM调制。  相似文献   
30.
Grey parrots (Psittacus erithacus) learn referential English labels when they view and interact with 2 humans who model vocal labeling and who demonstrate referentiality and functionality of a label (I. M. Pepperberg, 1990a). To test if both trainers are necessary, the authors contrasted 2-trainer modeling with training by 1 human who presented targeted labels to a bird in concert with appropriate items, who asked questions, and who would reward attempts at the label with the item. The bird was also tutored by either 1 or 2 interactive humans in conjunction with a conspecific who already used referential labels. Referential labels were learned from multiple live tutors but not a single trainer. Presence of a conspecific enhanced learning compared with single-trainer sessions but did not affect acquisition in 2-human sessions. Specific aspects of paired tutoring seem critical for acquiring referential vocal labels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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