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121.
George P. Knight Delfino Vargas‐Chanes Sandra H. Losoya Sonia Cota‐Robles Laurie Chassin Joanna M. Lee 《Journal of research on adolescence》2009,19(4):625-653
This study examines changes over time in ethnic affirmation/belonging and ethnic identity achievement, Spanish language use, English language use, Mexican/Mexican‐American affiliation/identification and Anglo affiliation/identification in a sample of Mexican‐American adolescents participating in a longitudinal study of juvenile offenders. The Multigroup Ethnic Identity Measure and the Acculturation Rating Scale for Mexican Americans‐II were completed by the Mexican‐American adolescents 7 times over a 3‐year period. The findings from longitudinal growth modeling analyses and growth mixture modeling analyses indicate that there is heterogeneity in the initial scores and changes over time on these variables that are related to markers for the cultural qualities of the home environment (i.e., generational status and mother's most frequent language use). In contrast to expectations, marginalized or assimilated acculturation trajectories/types were not overrepresented in this sample of adolescent offenders. Implications for our understanding of the nature of acculturation and enculturation processes and the way these processes are studied are discussed. 相似文献
122.
Patrice Dion Éric Caron‐Malenfant Chantal Grondin Dominic Grenier 《Population and development review》2015,41(1):109-126
We analyze the direct and indirect demographic contribution of immigration to the foreign‐origin composition of the Canadian population according to various projection scenarios over a century, from 2006 to 2106. More specifically, we use Statistics Canada's Demosim microsimulation model to assess the long‐term sensitivity to immigration levels and the frequency of mixed unions of the share of immigrants in Canada and of persons who have at least one ancestor who arrived after 2006. The results of the simulations show that the population renewal process through immigration happens at a fast pace in a high immigration and low fertility country such as Canada. Under the scenarios developed, immigrants who entered after 2006 and their descendants could form the majority of the population by 2058 at the earliest and by 2079 at the latest and could represent between 62 percent and 88 percent in 2106. They also show that mixed unions are a key element of the speed at which the changes are likely to occur in the long run. 相似文献
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Elena Berdasco‐Muñoz Léo‐Lyuki Nishibayashi Olivier Baud Valérie Biran Thierry Nazzi 《Infancy》2018,23(2):268-287
Infants born preterm have higher risks of developing linguistic deficits. Considering that the ability to segment words from fluent speech is crucial for lexical acquisition, Experiment 1 tested the ability of healthy extremely‐to‐late preterm infants to segment monosyllabic words at 6 months of postnatal age. Results establish basic segmentation skills in these infants. While we failed to find an effect of the degree of prematurity, this issue will need further exploration. Future studies will also have to specify the scope of these early segmentation skills, both in terms of the types of words segmented, the cues used to do so, and in terms of possible differences in performance between subgroups of preterm infants (e.g., based on gestational age or medical risks). Lastly, given that the preterm infants tested had a mean maturational age of 4 months, Experiment 2 explored monosyllabic segmentation in full‐term 4‐month olds. Infants succeeded at the task, providing the earliest developmental evidence of word segmentation in full‐term infants. These findings better specify the early trajectory of segmentation abilities in both full‐term and healthy, low‐risk preterm infants and support the proposal that prematurity might have a differential effect on the early acquisition of various linguistic levels. 相似文献
125.
Infant Sex Moderates the Effects of Maternal Pre‐ and Postnatal Stress on Executive Functioning at 8 Months of Age
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Saara Nolvi Henri Pesonen David J. Bridgett Riikka Korja Eeva‐Leena Kataja Hasse Karlsson Linnea Karlsson 《Infancy》2018,23(2):194-210
Previous studies report that early life stress, including maternal pre‐ and postnatal stress, has adverse effects on cognitive development and that these associations might be sex‐specific. However, no studies exist on early life stress and infant executive functioning (EF). The aim of this study was to examine the relationship between maternal pre‐ and postnatal stress and infant EF, and whether these associations are moderated by infant sex. Maternal prenatal depressive, general anxiety, and pregnancy‐specific anxiety symptoms were measured three times, and postnatal depressive and general anxiety symptoms were measured 6 months postpartum. Infant EF was assessed with a modified A‐not‐B task 8 months postpartum (N = 214). Maternal postnatal general anxiety predicted poorer EF in girls in comparison with boys. Moreover, there was a trend toward an interaction between prenatal anxiety and infant sex such that prenatal anxiety predicted infant EF differently in girls and in boys. No association was found between depressive symptoms or pregnancy‐specific anxiety symptoms and infant EF. These findings suggest that maternal anxiety may have sex‐specific effects on early EF and that pre‐ and postnatal stress may differently affect infant EF/cognitive development. The implications of these findings and important future directions are discussed. 相似文献
126.
Improving and measuring transparency in NGOs: A disclosure index for activities and projects
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J. David Cabedo Iluminada Fuertes‐Fuertes Amparo Maset‐LLaudes José Miguel Tirado‐Beltrán 《Nonprofit management & leadership》2018,28(3):329-348
Nongovernmental organizations (NGOs) are established not with the aim of making profits but rather to provide social values by implementing different projects and activities. Transmitting complete information about these projects to society is a key element of transparency, as they operate within an atmosphere of public trust. Although there is a large body of literature on transparency in NGOs from a global perspective, very little research has been conducted on transparency within the area of projects and activities. This study takes a deeper look at this line and contributes to the literature on transparency in NGOs by proposing an index to measure the information transparency of the projects implemented by these organizations. The index captures three dimensions of the information about the projects (technical, financial, and scope) and makes it possible to: analyze the level of transparency of the portfolio of projects, detect the specific aspects that could be improved in each organization, and carry out comparisons among organizations. 相似文献
127.
Shyness,Preference for Solitude,and Adolescent Internalizing: The Roles of Maternal,Paternal, and Best‐Friend Support
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Matthew G. Barstead Kelly A. Smith Brett Laursen Cathryn Booth‐LaForce Shakeena King Kenneth H. Rubin 《Journal of research on adolescence》2018,28(2):488-504
The researchers examined differential outcomes related to two distinct motivations for withdrawal (preference for solitude and shyness) as well as the possibility that support from important others (mothers, fathers, and best friends) attenuate any such links. Adolescents (159 males, 171 females) reported on their motivations to withdraw, internalizing symptoms, and relationship quality in eighth grade, as well as their anxiety and depression in ninth grade. Using structural equation modeling, the authors found that maternal support weakened the association between shyness and internalizing problems; friend support weakened the association between preference for solitude and depression; and friend support strengthened the association between shyness and depression. Results suggest that shy adolescents may not derive the same benefits from supportive friendships as their typical peers. 相似文献
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We study a system of two non-identical and separate M/M/1/? queues with capacities (buffers) C1 < ∞ and C2 = ∞, respectively, served by a single server that alternates between the queues. The server’s switching policy is threshold-based, and, in contrast to other threshold models, is determined by the state of the queue that is not being served. That is, when neither queue is empty while the server attends Qi (i = 1, 2), the server switches to the other queue as soon as the latter reaches its threshold. When a served queue becomes empty we consider two switching scenarios: (i) Work-Conserving, and (ii) Non-Work-Conserving. We analyze the two scenarios using Matrix Geometric methods and obtain explicitly the rate matrix R, where its entries are given in terms of the roots of the determinants of two underlying matrices. Numerical examples are presented and extreme cases are investigated. 相似文献