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971.
There is an increasing interest in alpha-range rhythms in the electroencephalogram (EEG) in relation to perceptual and attentional processes. The infant mu rhythm has been extensively studied in the context of linkages between action observation and action production in infancy, but less is known about the mu rhythm in relation to cross-modal processes involving somatosensation. We investigated differences in mu responses to cued vibrotactile stimulation of the hand in two age groups of infants: From 6 to 7 months and 13 to 14 months. We were also interested in anticipatory neural responses in the alpha frequency range prior to tactile stimulation. Tactile stimulation of infants’ left or right hand was preceded by an audiovisual cue signaling which hand would be stimulated. In response to the tactile stimulus, infants demonstrated significant mu desynchronization over the central areas contralateral to the hand stimulated, with higher mu peak frequency and greater contralateral mu desynchronization for older infants. Prior to the tactile stimulus, both age groups showed significant bilateral alpha desynchronization over frontocentral sites, which may be indicative of generalized anticipation of an upcoming stimulus. The findings highlight the potential of examining the sensorimotor mu rhythm in the context of infant attentional development.  相似文献   
972.

Niche partitioning reduces interspecific competition, facilitating coexistence. In urban ecosystems, however, habitat loss reduces species’ ability to spatially partition activity. Temporal partitioning may thus increase in urban areas as species, unable to avoid each other spatially, partition time to avoid competition. In Midwestern US cities, eastern gray squirrels (Sciurus carolinensis) and fox squirrels (S. niger) co-occur and compete for resources. We identified urban gray and fox squirrel activity patterns and how they vary with season, land cover, and among sites where they do and do not co-occur using camera-trap data. Both species’ activity patterns varied with season and canopy and impervious surface cover. Gray squirrel activity patterns varied in the presence of fox squirrels only in the fall, providing limited support for our temporal partitioning hypothesis. Temporal niche partitioning may thus play a role in supporting these species co-existence when competition is seasonally-elevated (e.g., fall hording), but appears less important in other seasons.

  相似文献   
973.
This article reexamines the living arrangements of children following their parents’ divorce, using Wisconsin Court Records, updating an analysis that showed relatively small but significant increases in shared custody in the late 1980s and early 1990s. These changes have accelerated markedly in the intervening years: between 1988 and 2008, the proportion of mothers granted sole physical custody fell substantially, the proportion of parents sharing custody increased dramatically, and father–sole custody remained relatively stable. We explore changes in the correlates of alternative custody outcomes, showing that some results from the earlier analysis still hold (for example, cases with higher total family income are more likely to have shared custody), but other differences have lessened (shared-custody cases have become less distinctive as they have become more common). Despite the considerable changes in marriage and divorce patterns over this period, we do not find strong evidence that the changes in custody are related to changes in the characteristics of families experiencing a divorce; rather, changes in custody may be the result of changes in social norms and the process by which custody is determined.  相似文献   
974.
975.
The life orientation test-revised (LOT-R) (Scheier et al. in Journal of Personality and Social Psychology 67:1063–1078, 1994) is a brief measure for assessing dispositional optimism. The aim of this study was to develop a Greek language version of the LOT-R and to assess the instrument’s psychometric properties. The LOT-R was translated and culturally adopted in Greek language, and the final version was administered, along with a questionnaire consisting socioeconomic characteristics and a single item measuring optimism, to 276 Greek speaking, hospital nurses (222 female, 54 male), aged 22–65 years (mean 37.8, SD 8.3). Results showed that the LOT-R has good internal consistency (Cronbach’s α = .71 and item total correlation coefficients from .27 to .73, a unitary structure, and stability over a 3-months period (r = .66). Moreover, the Greek version of the scale exhibited good convergent validity with single-item optimism scale (r = .73). Principal components analysis revealed a two-factor structure representing the constructs of optimism and pessimism. The Greek life orientation test revised appears to be a valid tool in assessing dispositional optimism in Greek speaking people and is expected to facilitate the examination of optimism in Greek speaking populations.  相似文献   
976.
A method is presented for analysing maternity history data to provide period estimates of parity progression ratios, birth intervals and related indices. This is applied to a sample of the marriage and maternity histories from the Census of England and Wales of 1971 and shows: (a) a general increase through the 1950s and into the 1960s in period estimates of marriage and parity progression ratios, especially in the progression from first to second birth; (b) a general acceleration of fertility with, again, the second birth interval becoming particularly short and compact; and (c) very steep declines in third and fourth birth progression ratios from the mid-1960s. Birth interval distributions altered during the period examined. Decomposition of a progression-based total fertility index shows change in the ratios for lower birth orders to have dominated the fertility upswing and declines in ratios for higher birth orders to have initiated the subsequent decline.  相似文献   
977.
This paper describes the use of a probability sample to survey differential fertility. 475 women were randomly selected from the 1941 Census of Canada to provide tests of the existence of five differentials: income, present age, age by marriage, schooling and distance from a city. The sample was limited to one province and to two contrasting values of each of the five differentials under study. Significant differences are found for the effective distance as well as for age at marriage and schooling. This is taken as signifying that the diffusion of the small-family pattern has a spatial dimension.  相似文献   
978.
We examined factors related to attitudes toward marriage and the importance of having children in both the US and Singapore. Path analysis indicated that life dissatisfaction leads to materialism, and both of these factors lead to favorable attitudes toward marriage, which leads to greater desire for children. Further analysis indicated this model was effective in explaining the difference in desire for children between Singaporeans and Americans, whereby Singaporeans have lower life satisfaction, higher materialism, and lower attitudes toward marriage and children. Materialistic standards of success were also related to the emphasis women placed on potential marriage partners’ earning capacity. As Singaporean women had higher materialistic standards, they also placed higher emphasis on potential mates’ earning capacity. Results suggest a consideration of psychological variables such as life satisfaction, materialism, and mate preferences may lead to a better understanding of larger-scale socioeconomic issues, including low fertility rates among developed East Asian countries.  相似文献   
979.
In 2010 the Danish regions started a new program of public health surveillance in collaboration with the national and local health authorities using the short form health survey (SF-12) for measuring and reporting on health related quality of life among the Danish adult population. The instrument has not, however, been validated in a Danish setting. The aim of this study was to assess the reliability and validity of the physical component summary (PCS) and the mental component summary (MCS) score of the 12-item short form health survey (SF-12) in a sample from Central Denmark Region. A total of 26,397 persons above the age of 25 were included in the analyses. Reliability was assessed by Cronbach’s α. The validity was assessed using known-groups comparisons and convergent validity. The factor structure was investigated through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The Cronbach’s α showed high reliability with a score of 0.90 and 0.85 for PCS and MCS respectively. The SF-12 discriminated well with respect to gender, age, educational status and long term illness. Individual items correlated higher with own hypothesized scales than with other scales and summary measures corroborating the convergent validity. The EFA gave a two-factor structure. Irrespective of the chosen rotation method (varimax and oblimin) the items related to PCS loaded on one factor and the items related to MCS loaded on another factor. The factor structure was validated with acceptable model-fit values in CFA. The SF-12 instrument is a reliable and valid measure of health related quality of life among the population of Central Denmark Region.  相似文献   
980.
The emergence of positive psychology has generated increased interest about the correlates of positive psychological functioning. Researchers have identified and studied various positive psychological constructs (e.g., hope, optimism, self-efficacy, gratitude, and life satisfaction) and found them to covary and to be positively associated with optimal human functioning and negatively associated with mental illness. This study of 528 college students examined the co-occurrence of selected positive psychological traits and explored their relations with a proposed second-order latent construct called covitality and with psychological well-being. Structural equation modeling examined each first-order positive psychology construct related to the second-order concept of covitality. Findings supported the second-order latent factor model of covitality, which was also significantly related to indicators of psychological well-being. Implications for theory development related to understanding positive human resources and applications within the context of college student populations are discussed.  相似文献   
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