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71.
Little is known about early life diet as a risk factor for early-onset persistent conduct problems (EOP CP). To investigate this, we used data from the Avon Longitudinal Study of Parents and Children, a UK-based prospective epidemiological birth cohort. 5727 mother-child pairs (49.9 % boys) monitored since pregnancy (delivery date between 1 April, 1991 and 31 December, 1992) reported intake of fish and processed foods at 32 weeks gestation and, for the child, at 3 years; EOP (n = 666) and Low conduct problem (Low CP, n = 5061) trajectories were measured from 4 to 13 years; hyperactivity and emotional difficulties were assessed in childhood (4–10 years) and early adolescence (12–13 years), in addition to potential confounding factors (family adversity, birth complications, income). Compared to Low CP, mothers of EOP children consumed less fish (p < 0.01) and more processed food (p < 0.05) prenatally, while EOP children consumed more processed food at 3 years (p < 0.05). For EOP, but not Low CP children, consuming less than two servings/week of fish (vs. two or more servings/week, p < 0.05), and one or more servings/day of processed food (vs. less than one serving/day, p < 0.01), was associated with higher emotional difficulties in early adolescence. Conclusions: Findings suggest that prenatal and postnatal diets high in processed food, and low in fish, associate with an EOP CP trajectory and co-occurring difficulties in early adolescence. As small effect size differences were found, further studies are needed to investigate the long-term impact of early unhealthy diet.  相似文献   
72.
Human conscious awareness is commonly seen as the climax of evolution. However, what function-if any-it serves in human behavior is still debated. One of the leading suggestions is that the cardinal function of conscious awareness is to integrate numerous inputs-including the multitude of features and objects in a complex scene-across different levels of analysis into a unified, coherent, and meaningful perceptual experience. Here we demonstrate, however, that integration of objects with their background scenes can be achieved without awareness of either. We used a binocular rivalry technique known as continuous flash suppression to induce perceptual suppression in a group of human observers. Complex scenes that included incongruent objects escaped perceptual suppression faster than normal scenes did. We conclude that visual awareness is not needed for object-background integration or for processing the likelihood of an object to appear within a given semantic context, but may be needed for dealing with novel situations.  相似文献   
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74.
The current study examined how work support resources and working from home influenced forms of work-family conflict (WFC) in employees at a large corporation. Scales measuring employee’s general WFC, time-based WFC, and strain-based WFC were used to evaluate the extent to which employees experienced work-induced conflict at home. Two forms of working at home were assessed, days worked at home and extra hours worked at home, and five variables measured the extent of one’s support resources: work social support, organizational support, individual consideration from one’s manager, idealized influence from one’s manager and contingent reward from one’s manager. We predicted that days worked at home would be negatively related to the three forms of WFC, while the extra hours worked at home would be positively related. Moreover, we hypothesized that the five support variables would moderate the relationship between extra hours worked at home and the types of WFC. The data supported some of the predictions, and the implications of these findings are discussed.  相似文献   
75.
This article presents the important, but overlooked, role that is played by grandparents in contemporary China as joint caregivers with parents in raising only children. Grounded on empirical data, collected through ethnographic and survey methods in urban China, the article identifies the ‘intergenerational parenting coalition’ as a culturally appropriate unit of analysis for understanding child rearing within the multigenerational family in China. The social forces that have given rise to the contemporary multigenerational family in China are reviewed. Qualitative analyses of four such families are used to illustrate the unique family dynamics and patterns of influence particular to the intergenerational parenting coalition.  相似文献   
76.
The role of gender in shaping the course and quality of adult-youth mentoring relationships was examined. The study drew on data from a large, random assignment evaluation of Big Brothers Big Sisters of America (BBSA) programs [Grossman, J. B., & Tierney, J. P. (1998). Does mentoring work? An impact study of the Big Brothers Big Sisters program. Evaluation Review, 22, 403-426], and focused on variables associated with youth’s relationships with their parents and mentors. At baseline, girls reported significantly lower levels of parental trust and higher levels of alienation from their parents than boys. Nonetheless, girls’ mentoring relationships lasted significantly longer than those of boys. Moreover, girls were less satisfied than boys in short- and medium-term relationships, but were more satisfied than boys in long-term relationships. Similarly, girls in long-term relationships rated mentoring as more helpful than either the boys or the girls in the shorter-term relationship groups. Particularly in light of the heightened mistrust and alienation from parents at baseline, and the role of improved parent relationships in mediating the effects of mentoring, the protective aspect of longer-lasting mentoring relationships may be particularly salient for girls.  相似文献   
77.
The primary auditory cortex is now known to be involved in learning and memory, as well as auditory perception. For example, spectral tuning often shifts toward or to the frequency of the conditioned stimulus during associative learning. As previous research has focused on tonal frequency, less is known about how learning might alter temporal parameters of response in the auditory cortex. This study addressed the effects of learning on the fidelity of temporal processing. Adult male rats were trained to avoid shock that was signaled by an 8.0 kHz tone. A novel control group received non-contingent tone and shock with shock probability decreasing over days to match the reduced number of shocks received by the avoidance group as they mastered the task. An untrained (nai ve) group served as a baseline. Following training, neuronal responses to white noise and a broad spectrum of tones were determined across the primary auditory cortex in a terminal experiment with subjects under general anesthesia. Avoidance conditioning significantly improved the precision of spike-timing: the coefficient of variation of 1st spike latency was significantly reduced in avoidance animals compared to controls and nai ves, both for tones and for noise. Additionally, avoidance learning was accompanied by a reduction of the latency of peak response, by 2.0-2.5 ms relative to nai ves and approximately 1.0 ms relative to controls. The shock-matched controls also exhibited significantly shorter peak latency of response than nai ves, demonstrating the importance of this non-avoidance control. Plasticity of temporal processing showed no evidence of frequency specificity and developed independently of the non-temporal parameters magnitude of response, frequency tuning and neural threshold, none of which were facilitated. The facilitation of temporal processing suggests that avoidance learning may increase synaptic strength either within the auditory cortex, in the subcortical auditory system, or both.  相似文献   
78.
Walking on music     
The present study focuses on the intricate relationship between human body movement and music, in particular on how music may influence the way humans walk. In an experiment, participants were asked to synchronize their walking tempo with the tempo of musical and metronome stimuli. The walking tempo and walking speed were measured. The tempi of the stimuli varied between 50 and 190 beats per minute. The data revealed that people walk faster on music than on metronome stimuli and that walking on music can be modeled as a resonance phenomenon that is related to the perceptual resonance phenomenon as described by Van Noorden and Moelants (Van Noorden, L., & Moelants, D. (1999). Resonance in the perception of musical pulse. Journal of New Music Research, 28, 43-66).  相似文献   
79.
80.
Leon Gumański 《Studia Logica》1983,42(2-3):129-137
The chief aim of the paper is to extend the calculusDSC 1 (see [4]) in such a way as to satisfy all the requirements listed in [4] as well as a further stipulation — called ‘the principle of uninvolvement’ — to the effect that neither deontic compatibility nor deontic incompatibility of codes (see [2]) should be presupposed in deontic logic.  相似文献   
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