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921.
922.
Soluble oligomeric forms of amyloid beta (AβO) are regarded as a main cause of synaptic and cognitive dysfunction in Alzheimer’s disease (AD) and have been a primary target in the development of drug treatments for AD. The present study utilized a mouse model of AD induced by intrahippocampal injection of AβO (10 μM) to investigate the effects of Gami-Chunghyuldan (GCD), a standardized multi-herbal medicinal formula, on the presentation of memory deficits and neurohistological pathogenesis. GCD (10 and 50 mg/kg/day, 5 days, p.o.) improved AβO-induced memory impairment as well as reduced neuronal cell death, astrogliosis, and microgliosis in the hippocampus. In addition, GCD prevented AβO-triggered synaptic disruption and cholinergic fiber loss. These results suggest that GCD may be useful in the prevention and treatment of AD.  相似文献   
923.
The national-level scenarios project NanoFutures focuses on the social, political, economic, and ethical implications of nanotechnology, and is initiated by the Center for Nanotechnology in Society at Arizona State University (CNS-ASU). The project involves novel methods for the development of plausible visions of nanotechnology-enabled futures, elucidates public preferences for various alternatives, and, using such preferences, helps refine future visions for research and outreach. In doing so, the NanoFutures project aims to address a central question: how to deliberate the social implications of an emergent technology whose outcomes are not known. The solution pursued by the NanoFutures project is twofold. First, NanoFutures limits speculation about the technology to plausible visions. This ambition introduces a host of concerns about the limits of prediction, the nature of plausibility, and how to establish plausibility. Second, it subjects these visions to democratic assessment by a range of stakeholders, thus raising methodological questions as to who are relevant stakeholders and how to activate different communities so as to engage the far future. This article makes the dilemmas posed by decisions about such methodological issues transparent and therefore articulates the role of plausibility in anticipatory governance.  相似文献   
924.

Objective

To examine the role of psychological type in older driver performance.

Methods

A convenience sample of 50 older adults was prospectively enrolled in the study. Each completed a demographic profile, the Myers–Briggs Type Indicator® (MBTI®) Step III™ instrument, a self-reported Safe Driving Behaviors Measure (SDBM), clinical tests and a standardized on-road driving evaluation yielding a fail/pass determination and Sum of Maneuvers Score (SMS).

Results

Participants (M age = 72.96, SD = 4.78) who had Extraversion and Judging preferences were better drivers than those with Introversion or Perceiving preferences. Those with Sensing vs. Intuition preferences rated themselves better on the SDBM (S = 317.62, N = 305.33; t(48) = 2.19, p = .03). Those with Introvert preferences failed the on-road course with sensitivity = .714, specificity = .767, area under the curve = .76, p = .03.

Conclusion

Our findings provide the basis for further research investigating personality and driving. Specifically, if the main findings are consistent in a representative sample of older drivers, personality testing may be added to a driving assessment battery. Future research must build on these findings to more clearly identify the risk associated with psychological type and examine how personality profiles can be used to keep older drivers on the road longer and more safely.  相似文献   
925.
Dominance and submission constitute fundamentally different social interaction strategies that may be enacted most effectively to the extent that the emotions of others are relatively ignored (dominance) versus noticed (submission). On the basis of such considerations, we hypothesized a systematic relationship between chronic tendencies toward high versus low levels of interpersonal dominance and emotion decoding accuracy in objective tasks. In two studies (total N = 232), interpersonally dominant individuals exhibited poorer levels of emotion recognition in response to audio and video clips (Study 1) and facial expressions of emotion (Study 2). The results provide a novel perspective on interpersonal dominance, suggest its strategic nature (Study 2), and are discussed in relation to Fiske's (1993) social-cognitive theory of power.  相似文献   
926.
Research on social identity contingencies suggests that situational cues, such as a numerical representation of social identities in a given social environment, can trigger identity-associated threat for individuals whose social identity is marginalized. Given that popular virtual worlds (e.g., Second Life [SL]) are often criticized for White-avatar dominance or White bias, we examined the psychological effects of the alleged White dominance in avatar-based virtual worlds by conducting two experiments in which participants read fictitious profiles of SL resident avatars. White and non-White participants were randomly assigned to view either a set of White-dominant avatar profiles or a set of racially diverse ones. After reading the profiles, participants had an opportunity to customize avatars using the SL interface. The findings of Experiment 1 (n=59) revealed that non-White participants exposed to the White-dominant avatar profiles, when compared with those exposed to the racially diverse profiles, reported significantly lower levels of sense of belonging and intention to participate in SL. Experiment 2 (n=64) demonstrated that non-White participants exposed to the White-dominant avatar profiles gave significantly higher estimation of the White user population within SL; the data also showed that exposure to the White-dominant avatar profiles resulted in a greater sense of limitation on skin customization among non-White participants than among White participants. The present research suggests that ethno-racial minorities, when exposed to avatar-based cues that signal White dominance, may perceive the virtual world as identity threatening, thereby feeling psychologically disconnected and detached from it. Implications regarding racial/ethnic diversity in virtual worlds are discussed.  相似文献   
927.
Prediction of complex behavioural tasks via relatively simple modelling techniques, such as logistic regression and discriminant analysis, often has limited success. We hypothesized that to more accurately model complex behaviour, more complex models, such as kernel-based methods, would be needed. To test this hypothesis, we assessed the value of six modelling approaches for predicting driving ability based on performance on computerized sensory-motor and cognitive tests (SMCTests?) in 501 people with brain disorders. The models included three models previously used to predict driving ability (discriminant analysis, DA; binary logistic regression, BLR; and nonlinear causal resource analysis, NCRA) and three kernel methods (support vector machine, SVM; product kernel density, PK; and kernel product density, KP). At the classification level, two kernel methods were substantially more accurate at classifying on-road pass or fail (SVM 99.6%, PK 99.8%) than the other models (DA 76%, BLR 78%, NCRA 74%, KP 81%). However, accuracy decreased substantially for all of the kernel models when cross-validation techniques were used to estimate prediction of on-road pass or fail in an independent referral group (SVM 73-76%, PK 72-73%, KP 71-72%) but decreased only slightly for DA (74-75%) and BLR (75-76%). Cross-validation of NCRA was not possible. In conclusion, while kernel-based models are successful at modelling complex data at a classification level, this is likely to be due to overfitting of the data, which does not lead to an improvement in accuracy in independent data over and above the accuracy of other less complex modelling techniques.  相似文献   
928.
Compared to neutral or happy stimuli, subliminal fear stimuli are known to be well processed through the automatic pathway. We tried to examine whether fear stimuli could be processed more strongly than other negative emotional stimuli using a modified subliminal affective priming paradigm. Twenty-six healthy subjects participated in two separated sessions. Fear, disgust and neutral facial expressions were adopted as primes, and 50% happy facial stimuli were adopted as a target to let only stronger negative primes reveal a priming effect. Participants were asked to appraise the affect of target faces in the affect appraisal session and to appraise the genuineness of target faces in the genuineness appraisal session. The genuineness instruction was developed to help participants be sensitive to potential threats. In the affect appraisal, participants judged 50% happy target faces significantly more 'unpleasant' when they were primed by fear faces than primed by 50% happy control faces. In the genuineness appraisal, participants judged targets significantly more 'not genuine' when they were primed by fear and disgust faces than primed by controls. These findings suggest that there may be differential priming effects between subliminal fear and disgust expressions, which could be modulated by a sensitive context of potential threat.  相似文献   
929.
930.
We examine how local religions influence derivative usage in the hedge fund industry. Measuring religiosity by the ratio of religious adherents in the county of a U.S. hedge fund headquarters, we find that religiosity is negatively related to the probability of hedge funds using derivatives for speculative purposes. In contrast, funds in regions with higher ratios of Catholics to Protestants are more likely to engage in speculation-based trading of derivatives. Finally, we show that the effects of local religion are more pronounced if the hedge fund size is small. Overall, our study highlights the significant role of local religion in shaping the purpose of hedge fund derivative usage.  相似文献   
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