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971.
Laidre ME 《Animal cognition》2008,11(2):179-187
Studies of intraspecific behavioral variability have documented cases where behaviors are present in some populations or groups but are absent in others. In some cases these differences cannot be explained by recourse to environmental or genetic variation, and may instead represent “traditions”. Despite many examples of animal traditions in acoustic communication, relatively few examples exist of gestural traditions. Here I report on a study of communication across eight captive groups of mandrills (Mandrillus sphinx) in which a prominent gesture (Hand extension) was unique to two groups. Habitat variability, genetic differences, and sampling bias were not sufficient to account for the gesture’s limited distribution across the study groups. Within the two groups where the gesture did occur only the juveniles in the group performed it, consistently directing it toward adults. Quantitative analysis of the contexts and responses associated with the gesture suggested that juveniles utilized it to provoke adults. Moreover, the gesture appeared to minimize the risk juveniles incurred while inciting adults, suggesting that repeated social interactions shaped the gesture’s form. Interestingly, both the groups where the gesture emerged contained few juveniles. With limited play partners, these juveniles may have resorted to harassing adults as an alternative social play outlet. The creation of this novel gesture may thus be due to the combined influence of a shortage of play partners and of the increased free time for playful social exploration afforded by captivity. Although juveniles frequently “eavesdropped” on dyadic interactions involving the gesture and would subsequently initiate an interaction with the recipient of the gesture, there was no definitive evidence for social transmission; the gesture could instead have been independently invented by each juvenile. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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Goal orientation is a multidimensional construct widely examined by social, organizational, educational, and sports psychology researchers. However, despite theoretical perspectives indicating that individuals can adopt or manifest more than one goal orientation simultaneously, researchers traditionally examine relationships between the goal orientation dimensions and outcome variables of interest independently. In contrast, this study was designed to examine whether individuals can be sorted into meaningful goal orientation profiles based on their scores on measures of learning, performance–approach, and performance–avoidance goal orientation, and the relationships between the resulting profiles and various dispositional and motivational variables. Our results indicated that a 4-profile solution best fit our data and that the 4 profiles differed uniquely across our dependent variables.  相似文献   
976.
Falls and fall-related injuries are a major problem for elderly persons. Most falls occur during walking and turning, and the risk of falling increases when attention is diverted to something besides walking. It is often difficult to standardize methods for testing balance and fall tendency in a clinically relevant setting. We describe the development of a system using a virtual environment (VE) to assess how attention demanding and unexpected events influence a person's capacity to control balance and movement. The hardware in the system consists of a head-mounted display (HMD), a magnetic tracker system, and two SGI computers. The software consists of the image generation of the VE and the management and visualization of motion tracking data. In a preliminary pilot study eight subjects (age 23-80) participated. Each subject walked on a normal floor and was visually presented a familiar outdoor environment in the HMD. They were exposed to different unexpected events, such as a virtual snowfall and tilting of the VE. Disturbances of balance and walking patterns such as changes in speed, stride length and balance reactions like slipping were observed. Two subjects experienced symptoms of cyber sickness with a SSQ score above 25 points. Walking with sensors only did not affect walking time, but in VE the subjects generally walked more slowly. Virtual tilting of the environment had an impact on balance performance during walking. This effect was not observed while the test subjects were walking in a virtual snowfall. The model needs further development but may hold a potential for clinical use.  相似文献   
977.
A number of recent papers have suggested that the series of time intervals produced in continuation tapping may have fractal properties. This proposition, nevertheless, was only based on the visual appraisal of graphical results, and was not statistically supported. In the present study, we applied the ARMA/ARFIMA modeling procedures proposed by Wagenmakers, Farrell, and Ratcliff (2005) to test for the presence of long-range dependencies in continuation tapping data. Our results demonstrate the presence of long-range dependencies in most series and offer strong support for the hypothesis that fluctuations in tapping series are fractal in nature.  相似文献   
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The current study examined the relationship between narcissism and vanity, and the degree these are predicted by the ‘Big Five’ personality traits and mating effort (ME) using a sample of 103 females recruited from a large beauty salon. Narcissism correlated with vanity at 0.72 (P < 0.001), and was associated positively with extraversion (E), ME and the subscales of vanity; narcissism was associated negatively with neuroticism (N) and agreeableness (A). Vanity correlated positively with E, conscientiousness, both subscales of narcissism, and ME, and negatively with N and A. A composite narcissism–vanity score was produced using principal components analysis, and used along with scores from the NEO-FFI-R to predict mating effort. The narcissism–vanity composite, low A and E significantly and independently predicted mating effort (adjusted R2 = 0.28, F(9.96) = 7.74, P < 0.001). These results show that mating effort is additionally predicted by narcissism as well as self-reported personality.  相似文献   
979.
To make technology research more effective and to deal with fierce cost competition, technology research should be more focused on radical innovation and needs to adopt a more end-user-focused approach. Product improvement is already quite often building on knowledge collected around consumers’ experiences with these products to come with a next, improved generation of products. However, in case of creating novel products from “scratch,” this will be more difficult. The user-centered research approach including insights, scenarios, and experience prototypes provides a good method to incorporate the consumer perspective in the earliest stages of the product creation process. The development of the Ambilight TV will be used as a case to illustrate this approach.  相似文献   
980.
When two sequential targets (T1, T2) are inserted in an RSVP stream of distractors, perception of T2 is impaired at intertarget lags shorter than 700 msec. Paradoxically, this deficit disappears when T2 is presented directly after T1 (lag-1 sparing). Visser, Bischof, and Di Lollo (1999) found that lag-1 sparing occurs only when T1 and T2 are presented in the same stream. In contrast, Shih (2000) obtained lag-1 sparing with targets insepa-rate streams. Four experiments addressed this inconsistency and revealed lag-1 sparing with targets in different streams, but only when observers had no foreknowledge of T1's location. We hypothesized that when T1 location is known, attention is focused narrowly on that stream; if T2 then appears in the other stream it is missed, and lag-1 sparing does not occur. When T1 location is not known, attention is focused broadly, encompassing both streams, and lag-1 sparing ensues.  相似文献   
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