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131.
Past studies have found equivocal support for the ability of young infants to discriminate infant‐directed (ID) speech information in the presence of auditory‐only versus auditory + visual displays (faces + voices). Generally, younger infants appear to have more difficulty discriminating a change in the vocal properties of ID speech when they are accompanied by faces. Forty 4‐month‐old infants were tested using either an infant‐controlled habituation procedure (Experiment 1) or a fixed‐trial habituation procedure (Experiment 2). The prediction was that the infant‐controlled habituation procedure would be a more sensitive measure of infant attention to complex displays. The results indicated that 4‐month‐old infants discriminated voice changes in dynamic face + voice displays depending on the order in which they were viewed during the infant‐controlled habituation procedure. In contrast, no evidence of discrimination was found in the fixed‐trial procedure. The findings suggest that the selection of experimental methodology plays a significant role in the empirical observations of infant perceptual abilities. 相似文献
132.
In this article, we describe a straightforward method for solving the probability of at least one malignant cell by time t, and the associated hazard function, in the general (i.e., nonhomogeneous) two-stage Moolgavkar-Venzon-Knudson (MVK) model of cancer. The method consists of solving four coupled ordinary differential equations derived from the Kolmogorov backward equations for this process. The relationship of this method to previously proposed solutions is discussed. 相似文献
133.
21世纪各个国家特别是亚洲各国进入了发展的新阶段。亚洲在经济发展中实现了建设性的双边伙伴关系。但是亚洲国家形成“与西方传统不同的亚洲国际关系模式”仍然任重道远。作者认为,亚洲共同的文化认同可以发挥重要作用,理应把亚洲国家特别是两个人口最多的国家中国和印度团结起来,全面实现“亚洲共同体”的战略目标。 相似文献
134.
In multiple linear regression analysis, each observation affects the fitted regression equation differently and has varying influences on the regression coefficients of the different variables. Chatterjee & Hadi (1988) have proposed some measures such as DSSEij (Impact on Residual Sum of Squares of simultaneously omitting the ith observation and the jth variable), Fj (Partial F-test for the jth variable) and Fj(i) (Partial F-test for the jth variable omitting the ith observation) to show the joint impact and the interrelationship that exists among a variable and an observation. In this paper we have proposed more extended form of those measures DSSEIJ, FJ and FJ(I) to deal with the interrelationships that exist among the multiple observations and a subset of variables by monitoring the effects of the simultaneous omission of multiple variables and multiple observations. 相似文献
135.
Men,women, and sustainability 总被引:1,自引:1,他引:0
Dr. Bobbi S. Low 《Population and environment》1996,18(2):111-141
136.
Tattling on siblings was observed in 40 families with 2- and 4-year-old children. All but 5 children reported sibling misbehaviour to parents with younger siblings tattling largely to recruit parental help in resolving conflict issues, and older siblings tattling both in the context of conflict and merely to inform parents of their siblings' misbehaviour. Parents rarely reprimanded children for tattling, but either ignored it, or responded to information in tattlers' reports regardless of context or whether older or younger children tattled. Children did not tattle equally on all sibling transgressions, but emphasized physical aggression and property damage, issues that also elicited parental discipline. Tattling is discussed in relation to children's understanding of the dynamics and moral standards of family life. 相似文献
137.
Oommen TK 《International migration (Geneva, Switzerland)》1989,27(3):411-425
2 views on "brain drain" exist: 1) LDCs lose their enormous investments on higher education when skilled people migrate to other countries and 2) LDCs are exaggerating the problem and only a few skilled people migrate at 1 time. India does not completely lose its investment in education when professionals migrate, since the migrants still contribute to knowledge and also send remittances to relatives in India. Unemployed educated people would cause a greater drain on India's resources than educated migrants. The author prefers the phrase migration of talent to brain drain, since the former indicates a 2-way movement. Most migrants from LDCs are students. About 11,000 university graduates leave India every year for advanced study and/or work. A conservative estimate is that 2500 will remain abroad permanently. Most professionals who migrate go to the US and Canada. Factors promoting migration include 1) unemployment, 2) immigration rules, 3) colonial links, 4) financial incentives and material benefits, 5) pursuit of higher education, 6) improvement of working conditions and facilities, 7) avoidance of excessive bureaucratic procedures, and 8) compensation for the mismatch between Indian education and employment. Reasons for returning to India include 1) deference to wives who were unable to adjust to a foreign way of life, 2) contributing to Indian development, and 3) racial discrimination. It will probably not be possible to lure back migrants who left for material reasons. Attractive job offers could entice back those who left for advanced training. To encourage the return of those who left to pursue high quality research, India must 1) increase expenditure on research and development, possibly through the private industrial sector, 2) promote travel to other countries for professional enrichment, and 3) improve conditions of research work. The article concludes with an analysis of migration of talent from 3 perspectives: 1) the individual, 2) the nation-state, and 3) the world as a whole. 相似文献
138.
This article examines the origins of physicians and nurses who were admitted as permanent immigrants to the US from 1962-1979. Data are mainly from the Immigration and Naturalization Service. Countries used in the developmental analysis are only those whose population was estimated at 1 million or more as of mid-1979, encompassing 99% of the physicians and 97% of the nurses. Life expectancy at birth is the criterion used to differentiate origin countries by developmental dimension of health status. During the study period, health workers constituted about 30% of immigrants admitted to the US; of these, nurses and physicians constituted 72-82% throughout the study period. The period 1962-1979 has 4 distinct phases, marked by important legislative and/or policy changes; 1) 1962-1965, when the McCarran-Walter Act prevailed; 2) ending in 1968, the 2nd phase covers the transition mandated under the 1965 Immigration Act, which encouraged physician immigration; 3) the 3rd phase, 1969-1976, covers the transition to the 1976 Immigration and Nationality Act amendments; and 4) the 4th stage is 1977-1979. Results show that 1) under the McCarran-Walter Act, North America became the dominant physician source; 2) from 1966-1968, Asia attained dominance as the physician source and became even more predominant after 1968; 3) North America produced relatively few physicians in the early 1970s; 4) Europe produced substantially fewer physicians in the 1970s than in the 1960s; 5) South America, Africa, and Oceania were the lowest contributors of physicians; 6) during the McCarran-Walter years, North America and Europe produced almost 90% of nurses admitted into the US; 7) the 1965 Immigration Act and its aftermath resulted in Asia becoming the dominant source of nurses; 8) prior to the 1965 Immigration Act, Canada generated 20% of the aggregate number of physicians; 9) the Philippines surpassed Canada during the transition and India led after the transition; and 10) Canada supplied 30% of the nurses up through the transition, with the Philippines in the lead 1969-1979. Low health status countries were a relatively minor nurse source. Health status at the origin was a far less significant determinant of physician immigration than that of nurses. English language high and low health status country groups produced substantially more physician and nurse immigrants that their corresponding non-English language counterparts. The US attracted more physicians and nurses from less developed countries than more developed countries after 1968. 相似文献
139.
Y. K. Ng 《Social Choice and Welfare》1989,6(2):87-101
Individual preferences inconsistent with personal welfare caused neither by ignorance nor by a positive consideration for the welfare of others are defined as (welfare) irrational. Sources of irrationality (rigid adherence to moral principles, excessive fear of danger, excessive tempetation of pleasure, revenge, inertia, faulty telescopic faculty, the fallacy of diminishing marginal utility of utility, etc.) are discussed. An evolutionary explanation of irrationality is suggested and some implications for individual decision and social policy indicated.I am grateful to two anonymous referees for comments. 相似文献
140.