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991.
Hill HD Morris PA Castells N Walker JT 《Journal of policy analysis and management》2011,30(2):310-333
This study uses data from an experimental employment program and instrumental variables (IV) estimation to examine the effects of maternal job loss on child classroom behavior. Random assignment to the treatment at one of three program sites is an exogenous predictor of employment patterns. Cross-site variation in treatment-control differences is used to identify the effects of employment levels and transitions. Under certain assumptions, this method controls for unobserved correlates of job loss and child well-being, as well as measurement error and simultaneity. IV estimates suggest that maternal job loss sharply increases problem behavior but has neutral effects on positive social behavior. Current employment programs concentrate primarily on job entry, but these findings point to the importance of promoting job stability for workers and their children. 相似文献
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Mexican?CAmerican adolescents are at an elevated risk for adjustment difficulties. In an effort to identify parenting practices that can affect the adjustment of Mexican?CAmerican youth, the current study examined parents?? promotion of psychological autonomy and parents?? psychological control as perceived by Mexican?CAmerican early adolescents, and explored their associations with adolescents?? adjustment in the context of acculturation. In 5th grade, 134 (54.5% female) Mexican?CAmerican adolescents reported on their acculturation level and the parenting practices of their mothers and fathers. In 5th and 7th grade, adolescents also reported on their depressive symptoms, number of delinquent friends, and self-worth. Perceptions of promotion of psychological autonomy and of psychological control were positively correlated. However, perceptions of more promotion of psychological autonomy and of less psychological control predicted fewer depressive symptoms 2 years later. Perceptions of more promotion of psychological autonomy also predicted fewer delinquent friends two years later. Finally, perceptions of more promotion of psychological autonomy predicted higher self-worth only among less acculturated adolescents. The study underscores the roles that promotion of psychological autonomy and psychological control may play in Mexican?CAmerican children??s well-being during early adolescence. 相似文献
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Four novel alkyl 2-cyanoacrylate monomers (alkyl=1-cyanoethyl, 2-cyanoethyl, trideuteromethyl and pentadeuteroethyl) have been tested for their ability to develop latent fingermarks that can then be visualized using mid-infrared spectral (chemical) imaging. Each of the four monomers was chosen for its potential to produce a strong, isolated infrared spectral band in its corresponding polymer (to provide spectral contrast against most backgrounds), as well as for its potential ability to be fumed onto fingermarks in the manner of conventional ethyl 2-cyanoacrylate (superglue). With the exception of the 2-cyanoethyl 2-cyanoacrylate, which had to be fumed under reduced pressure, all of the monomers were found to be sufficiently volatile to be fumed in a conventional fuming cabinet. All four monomers polymerized selectively on fingermark ridges on a variety of non-porous and semi-porous surfaces, leading to excellent development of the fingermarks. Unfortunately, although high quality mid-infrared spectral images of the fingermarks could be formed for all of the polymers at various frequencies, the new CN or CD stretching vibrations did not give rise to strong enough absorption intensities for good contrast on difficult backgrounds such as polymer banknotes. However, in the 1-cyanoethyl 2-cyanoacrylate polymer, the presence of the additional nitrile group had the unintended but desirable effect of shifting the strong CO absorption to higher frequencies, moving it away from interfering banknote absorptions. This enabled fingermark contrast to be achieved even against the intaglio printing on the banknotes. 相似文献
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Previous studies have examined the effects of heating on teeth; however, none have identified characteristics that allow analysts to differentiate traumatic from heat-induced fractures. This study examined our ability to discern notable differences in preincineration traumatic fractures and heat-induced fractures in postincineration dentition. Twelve anterior dental specimens were subjected to blunt force trauma while a second set were not. All 24 samples were then incinerated in a muffle furnace at a peak temperature (900°C) consistent with house fires. The specimens were subsequently examined with a scanning electron microscope to identify and compare heat-induced and traumatic fractures. The results obtained during examination yielded no differences between the features displayed by specimens that had been inflicted with preincineration trauma and those that did not. Unlike bone, distinguishing features for the differentiation of traumatic and heat-induced fractures could not be compiled. 相似文献
999.
Scott Wolford 《国际相互影响》2014,40(4):506-532
I analyze a two-level game in which a leader bargains over the spoils of international bargaining with a domestic opposition that can threaten her with a coup or revolution. While fighting an international war shrinks the domestic pie, it also alters the distribution of domestic power. This has three main implications. First, if war will undermine the opposition, fighting may be so attractive that leaders demand more for peace than foreign states are willing to give, leading to war. Second, if war will bolster the opposition, leaders accept harsh terms to avoid fighting—strategic selection that has implications for the observed relationship between war and political survival. Finally, prospective shifts in the distribution of domestic power caused by war can reduce the effects of international asymmetric information, though the result may be to increase or decrease the chances of war. 相似文献
1000.
Scott H. Decker David C. Pyrooz Gary Sweeten Richard K. Moule Jr. 《Journal of Quantitative Criminology》2014,30(4):577-598