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111.
Barry M. Lester Cynthia T. Garcia-Coll Marta Valcarcel 《Journal of youth and adolescence》1988,18(3):231-243
Deficits in parenting behavior in adolescent mothers could be due to the adolescent mother's perception of her infant's behavior. The aim of this study was to compare how adolescent and adult mothers perceive the crying behavior of their newborns. The 19 adolescent and 18 adult mothers listened to a tape recording of their infants' crying and rated the characteristics of the cry on 12 seven-point scales. The sample included newborns with normal growth and newborns with compromised growth. Acoustic characteristics of the cries were extracted by computer. Adult mothers rated the cries of their infants with compromised growth toward the negative end of the scales. By contrast, adolescent mothers rated the cries of their infants with compromised growth toward the positive end of the scales. Acoustic analysis showed that the cries of the infants with compromised growth were higher pitched and more variable than the cries of infants with normal growth. Correlations between the cry ratings and the acoustic analysis showed that for adult mothers, higher pitched and more variable cries were associated with negative ratings. For adolescent mothers, higher pitched and more variable cries were associated with more positive ratings. The findings suggest that adolescent mothers differ in the perception of their infant's behavior, which may have implications for later parenting behavior.This research was supported by a grant from the Ford Foundation.Received Ph.D. from Michigan State University. Main Research interests are infant crying, determinants of neontal and infant development, assessment of preterm and at-risk infants.Received Ph.D. from Harvard University. Main research interests are sociocultural aspects of development, teenage pregnancy, infant temperament, and psychophysiology.Main research interests have been in maternal and infant interactions of high risk infants. 相似文献
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A Global Model for Forecasting Political Instability 总被引:2,自引:0,他引:2
Jack A. Goldstone Robert H. Bates David L. Epstein Ted Robert Gurr Michael B. Lustik Monty G. Marshall Jay Ulfelder Mark Woodward 《American journal of political science》2010,54(1):190-208
Examining onsets of political instability in countries worldwide from 1955 to 2003, we develop a model that distinguishes countries that experienced instability from those that remained stable with a two-year lead time and over 80% accuracy. Intriguingly, the model uses few variables and a simple specification. The model is accurate in forecasting the onsets of both violent civil wars and nonviolent democratic reversals, suggesting common factors in both types of change. Whereas regime type is typically measured using linear or binary indicators of democracy/autocracy derived from the 21-point Polity scale, the model uses a nonlinear five-category measure of regime type based on the Polity components. This new measure of regime type emerges as the most powerful predictor of instability onsets, leading us to conclude that political institutions, properly specified, and not economic conditions, demography, or geography, are the most important predictors of the onset of political instability. 相似文献
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Daniel C. Butler M.D. Cynthia Schandl M.D. Ph.D. Madison Hyer M.S. Susan Erin Presnell M.D. 《Journal of forensic sciences》2020,65(2):508-512
Vitreous fluid sampling for postmortem chemistry analysis is discouraged in pediatric forensic cases involving head trauma due to the risk of introducing retinal artifacts. Aqueous fluid is physically separated from the posterior chamber of the eye, and therefore, unlikely to produce vitreal artifact when sampled. Analysis of aqueous fluid is therefore proposed as a substitute for vitreous. Vitreous and aqueous fluid was sampled concurrently from 28 pediatric and 55 adult decedents, and sodium (Na), potassium (K), chloride (Cl), urea nitrogen (UN), creatinine (Cr), and glucose (Glc) concentrations were compared. Significant correlation existed between all analytes regardless of age or postmortem interval, and linear regression equations were derived. Aqueous concentrations were generally higher than vitreous for Na, K, and Cr and were marginally lower for Cl, UN, and Glc. Assuming vitreous fluid as a standard for correlating postmortem chemistry to antemortem serum values, aqueous may be a viable substitute for vitreous when expected differences are considered. 相似文献
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This paper compares educational and financial outcomes in early adulthood for four groups of men and women: those who never experienced a nonmarital adolescent pregnancy, those who ended a nonmarital adolescent pregnancy by abortion, those who married or cohabited and became parents in response to an adolescent pregnancy, and those who became parents but did not marry or cohabit following an adolescent pregnancy. The analyses are based on self-reports of 6,074 young men and women who were first surveyed as seventh grade students in Houston, Texas in 1971 and surveyed again between 1980 and 1988. Educational and financial outcomes in adulthood vary significantly depending on the occurrence of a nonmarital adolescent pregnancy, the resolution of nonmarital adolescent pregnancy, and the age at which adolescent pregnancy occurs. Results are discussed in relation to public policies encouraging family formation and educational support and occupational training for teen parents. 相似文献