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181.
A modified form of Nathanson and Becker's (1983) Health Belief Model Questionnaire and other measures designed to assess cognitive processing were administered to low-income black adolescent female clients of an inner-city comprehensive health care clinic. The purpose of the study was to explore determinants of sexual activity and contraceptive use. Subjects were classified as not sexually active (n = 50), sexually active/noncontracepting (n = 20), or sexually active/contracepting (n = 72). Not sexually active subjects tended to be younger, more career motivated, to have a father at home, to be more influenced by family values, and to have more conservative attitudes regarding adolescent sexuality than did sexually active subjects. Sexually active/noncontracepting subjects tended to report fewer benefits and more barriers to the use of contraception. Level of cognitive processing did not differ among the three groups, but was at a lower-than-expected level for age. Finally, inconsistent contraceptive use was common to both sexually active groups.  相似文献   
182.
Abstract

Optic flow (OF) has been utilized to investigate the sensory integration of visual stimuli during postural control. It is little known how the OF speed affects the aging brain during the sensory integration process of postural control. This study was to examine the effect of OF speeds on the brain activation using functional near-infrared spectroscopy (fNIRS) and postural sway between younger and older adults. Eleven healthy younger adults (5M/6F, age 22?±?1-year-old) and ten healthy older adults (4M/6F, age 71?±?5-year-old) participated in this study. A virtual reality headset was used to provide the OF stimulus at different speeds. A forceplate was used to record the center-of-pressure to compute the amplitude of postural sway (peak-to-peak). Compared with younger adults, older adults showed significantly increased activation in the OF speed of 10?m/s and decreased activation in the OF speed of 20?m/s in the left dorsolateral prefrontal cortex. Older adults also showed decreased activation in the left temporoparietal region (VEST) in the OF speed of 20?m/s. A significant difference in peak-to-peak was found between groups. Our results indicated that age might be associated with the ability to process fast OF stimulation.  相似文献   
183.
The benefits of parental involvement in children’s education have been well established but increasing evidence suggests that overparenting may have adverse effects on children. The question of whether excessive parental involvement hinders children’s academic and psychosocial development warrants further investigations. This study examined the associations of parental educational involvement at home and in school with academic performance and psychological health of 507 Chinese Grade 3 schoolchildren in Hong Kong. Parents reported on their level of involvement in children’s schooling and their children’s psychosocial issues. Children were surveyed to determine their school engagement, and their Chinese language and mathematics attainment was assessed. We also explored the underlying mechanism by testing children’s engagement with school as a mediator of the relationships. Our results showed that home-based parental educational involvement was positively associated with children’s language competence and psychosocial wellbeing, and the associations were linked through engaging children with school. However, the benefits reached a plateau at higher level of parental involvement in children’s learning at home. School-based parental involvement had an indirect effect on children’s prosocial behavior through school engagement. These findings highlight the significance of optimal level of parental involvement in children’s education at home for children’s development.  相似文献   
184.
In the present research, the authors hypothesized that additive counterfactual thinking mind-sets, activated by adding new antecedent elements to reconstruct reality, promote an expansive processing style that broadens conceptual attention and facilitates performance on creative generation tasks, whereas subtractive counter-factual thinking mind-sets, activated by removing antecedent elements to reconstruct reality, promote a relational processing style that enhances tendencies to consider relationships and associations and facilitates performance on analytical problem-solving tasks. A reanalysis of a published data set suggested that the counterfactual mind-set primes previously used in the literature tend to evoke subtractive counterfactuals. Studies 1 and 2 then demonstrated that subtractive counterfactual mind-sets enhanced performance on analytical problem-solving tasks relative to additive counterfactual mind-sets, whereas Studies 3 and 4 found that additive counterfactual mind-sets enhanced performance on creative generation tasks relative to subtractive counterfactual mind-sets.  相似文献   
185.
Recent research indicates that adjudicated female youth have higher rates of mental health problems and histories of trauma exposure and abuse relative to adjudicated male youth. These differences are important for gender-specific assessment, intervention, and management strategies. We replicated a subtyping strategy for adjudicated female youth based on mental health screening data from the Massachusetts Youth Screening Instrument-2 (MAYSI-2) by investigating subtype differences on trauma symptoms, abuse history, and other background variables. Cluster analysis of the standard MAYSI-2 scales revealed a three cluster solution replicating results from a prior study. Additionally, results indicated expected differences between female youth with mental health problems compared to those without mental health problems with co-occurring female youth (i.e., self-reported mental health and substance abuse problems) having have greater mental health problems and more extensive abuse histories compared to other subtypes.  相似文献   
186.
The purpose of this study was to examine the relationship between narcissism and romantic attraction in a collectivistic culture (i.e., Thailand). In Study 1, participants completed a measure of narcissism and rated their attraction to four potential romantic partners. There was an overall preference across participants for caring targets. Additionally, high narcissists were more attracted to admiring and high status targets than were low narcissists. A similar pattern of results was found in Study 2 with targets that were either high caring/low status or high status/low caring. Overall, caring in a partner was highly valued in a collectivistic culture, but narcissism still predicted attraction to targets who offered the potential for self-enhancement. These findings suggest that classically Western self-enhancement can be found in Eastern samples; however, to uncover these self-enhancement processes, researchers might need to use a personality variable such as narcissism.  相似文献   
187.
The partial derivatives of the squared error loss function for the metric unfolding problem have a unique geometry which can be exploited to produce unfolding methods with very desirable properties. This paper details a simple unidimensional unfolding method which uses the geometry of the partial derivatives to find conditional global minima; i.e., one set of points is held fixed and the global minimum is found for the other set. The two sets are then interchanged. The procedure is very robust. It converges to a minimum very quickly from a random or non-random starting configuration and is particularly useful for the analysis of large data sets with missing entries.This paper benefits from many conversations with and suggestions from Howard Rosenthal.  相似文献   
188.
The effect of spacing in relation to word segmentation was examined for four groups of non-native Chinese speakers (American, Korean, Japanese, and Thai) who were learning Chinese as second language. Chinese sentences with four types of spacing information were used: unspaced text, word-spaced text, character-spaced text, and nonword-spaced text. Also, participants' native languages were different in terms of their basic characteristics: English and Korean are spaced, whereas the other two are unspaced; Japanese is character based whereas the other three are alphabetic. Thus, we assessed whether any spacing effects were modulated by native language characteristics. Eye movement measures showed least disruption to reading for word-spaced text and longer reading times for unspaced than character-spaced text, with nonword-spaced text yielding the most disruption. These effects were uninfluenced by native language (though reading times differed between groups as a result of Chinese reading experience). Demarcation of word boundaries through spacing reduces non-native readers' uncertainty about the characters that constitute a word, thereby speeding lexical identification, and in turn, reading. More generally, the results indicate that words have psychological reality for those who are learning to read Chinese as a second language, and that segmentation of text into words is more beneficial to successful comprehension than is separating individual Chinese characters with spaces.  相似文献   
189.
190.
Radio-frequency local positioning systems (LPS) have the potential to provide accurate location information about sport players for performance analysis, making available for study the emergent nature of interpersonal coordination and collective decision-making behaviour among players in both indoor and outdoor sports. However, no available publications have validated the performance of LPS for indoor sports. The objective of this study was to validate the performance of an LPS in an indoor venue and to compare it to performance observed in an outdoor venue using static and dynamic measurements. Our results showed that the absolute positioning errors obtained from the static measurements of the LPS were comparable for both indoor and outdoor venues, with mean errors of 12.1?cm outdoors and 11.9?cm indoors. From the dynamic measurements, we analysed the relative position error and the distance estimation performance of the system. The 90th-percentile relative position errors were 28?cm for the indoor venue versus 18?cm for the outdoor venue. On average, the LPS overestimated the distance travelled, and the performance was similar for both indoor and outdoor venues. On a linear course, the mean errors of the distance estimates were 2.2% of the total distance indoors and 1.3% outdoors, and on a nonlinear course, they were 2.7% indoors and 3.2% outdoors.  相似文献   
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