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81.

As compared with conventional vaccine production systems, plant-made vaccines (PMVs) are said to enjoy a range of advantages including cost of production and ease of storage for distribution in developing countries. In this article, we introduce the science of PMV production, and address ethical issues associated with development and clinical testing of PMVs within three interrelated domains: PMVs as transgenic plants; PMVs as clinical research materials; and PMVs as agents of global health. We present three conclusions: first, while many of the ethical issues raised by PMVs are familiar, PMVs add a new dimension to old issues, and raise some novel issues for ethicists and policy-makers; secondly, it is premature to promise broad applicability of PMVs across the developing world without having demonstrated their feasibility; thirdly, in particular, proponents of PMVs as a solution to global health problems must, as a condition of the ethical conduct of their research, define the commercial feasibility of PMVs for distribution in the developing world.  相似文献   
82.
Evaluations of methodological assessments sometimes show similar, sometimes different patterns of findings reflective of different approaches to the same problem. In this study, frequencies of behaviors of infants and mothers in two cultures based on continuous coding were compared with frequencies based on time-sampling, and resulting patterns of findings were evaluated. Time-sampling and continuous coding give different estimates of absolute frequency of typical infant and maternal behaviors between individuals and between cultural groups. However, time-sampling adequately preserves the relative ranking of infant and mother behaviors among individuals and between cultural groups. If research is concerned with the relative standing of individuals and/or groups on frequency of infant or maternal behavior, then (under specified circumstances) time-sampling and continuous coding yield comparable results.  相似文献   
83.
The phenotypic and genetic factor structure of performance on five Multidimensional Aptitude Battery (MAB) subtests and one Wechsler Adult Intelligence Scale—Revised (WAIS-R) subtest was explored in 390 adolescent twin pairs (184 monozygotic [MZ]; 206 dizygotic (DZ)). The temporal stability of these measures was derived from a subsample of 49 twin pairs, with test–retest correlations ranging from .67 to .85. A phenotypic factor model, in which performance and verbal factors were correlated, provided a good fit to the data. Genetic modeling was based on the phenotypic factor structure, but also took into account the additive genetic (A), common environmental (C), and unique environmental (E) parameters derived from a fully saturated ACE model. The best fitting model was characterized by a genetic correlated two-factor structure with specific effects, a general common environmental factor, and overlapping unique environmental effects. Results are compared to multivariate genetic models reported in children and adults, with the most notable difference being the growing importance of common genes influencing diverse abilities in adolescence.  相似文献   
84.
The effect of morphological repetition at lag 0 and at lag 15 on lexical decision was investigated in Hebrew with three types of relation between prime and target. In the semantic-plus-morphological condition (SM), the prime and the target in each pair were two semantically related derivatives of the same root. In the “pure morphological” condition (M), the prime and the target derived from the same root, but their semantic association was very low, or nonexistent. In the semantic priming condition (S), primes and targets were semantically associated but were not morphologically related. The pure semantic relationship produced a significant facilitation at lag 0 that disappeared completely at lag 15. The pure morphological relation produced (smaller but) significant facilitation at lag 0 that was not attenuated at lag 15. When prime and target were semantically as well as morphologically related, the facilitation at lag 0 was similar to semantic priming, whereas at lag 15 it was similar to the pure morphological effect. Significant repetition effects at both lags were also found with non-words that shared the same (nonsensical) root and differed with respect to real derivational affixes. The differential time course for facilitation due to semantic and morphological relatedness suggests distinct underlying processes, although at lag 0 it is possible that semantic relatedness may augment the morphological repetition effect. Morphological repetition probably facilitates the retrieval of lexical information that, under certain circumstances, is necessary for lexical decision.  相似文献   
85.
86.
Shepela  Sharon Toffey  Levesque  Laurie L. 《Sex roles》1998,38(7-8):589-611
This study of 369 undergraduate students (59%female and 41% male, 4.7% African-American, 2%Latino/a-American, 3.6% International, and 88%White-American) found that both women and men weresexually harassed by faculty and other students with a similarlyhigh frequency. More subtle forms of sexually harassingbehaviors were experienced than were the more severebehaviors from both faculty and students. A greater tolerance for sexually harassing behaviors fromfaculty than peers was found. While more women than menused the label sexual harassment, few students of eithergender who experienced specific harassing behaviors said they had experiencedinappropriate behavior, and of those who said they hadexperienced inappropriate behavior, a very lowpercentage said they had experienced sexual harassment.It is hypothesized that the frequency of these behaviors is partlyresponsible for the lack of labeling.  相似文献   
87.
Brown  Laura B.  Uebelacker  Lisa  Heatherington  Laurie 《Sex roles》1998,38(3-4):253-268
This study examined men's and women'sself-presentation of academic achievement in aninteractional context. First-year college students wereled to expect an interaction with a peer to discussacademic achievement. However, the peer was actually aconfederate who portrayed his or her achievement in aboastful, moderate, or self-deprecating manner. Prior tothe anticipated interaction, subjects were induced to describe their own academic achievement andmake predictions about their first-semester grade pointaverages (GPAs) to be shared with the peer. Men's GPApredictions were highest in the boastful condition (and higher than their actual GPAs), nexthighest in the moderate condition, and lowest (and lowerthan their actual GPAs) in the self-deprecatingcondition. Women's predicted GPAs,unexpectedly,didnotvary by condition. Women were less comfortable inpredicting their GPAs than men, and there was a tendencyfor men to be more comfortable than women whileobserving the boastful peer and women to be morecomfortable than men while observing the self-deprecatingpeer. Results are discussed with regard to past researchand self-in-relation theory.  相似文献   
88.
Sixty-four checks were cashed in a field examination of sex role discrimination using a non-sex-role stereotyped (neutral role) task. Experimenter (customer) sex, subject (teller) sex, amount of the check, and bank branch were varied to produce a 2 × 2 × 2 × 2 design. Transaction times were longer for female customers than for male customers, and were longer with male tellers than with female tellers. Results were interpreted as supporting the hypothesis of greater sex role salience in cross-sex, as compared with same-sex dyads. Suggestions are made for further research using neutral-role tasks to better define certain role concepts.  相似文献   
89.
An inexpensive continuous interference-filter monochromator is described.  相似文献   
90.
Children's family obligations involve assistance and respect that children are expected to provide to immediate and extended family members and reflect beliefs related to family life that may differ across cultural groups. Mothers, fathers and children (N = 1432 families) in 13 cultural groups in 9 countries (China, Colombia, Italy, Jordan, Kenya, Philippines, Sweden, Thailand and United States) reported on their expectations regarding children's family obligations and parenting attitudes and behaviours. Within families, mothers and fathers had more concordant expectations regarding children's family obligations than did parents and children. Parenting behaviours that were warmer, less neglectful and more controlling as well as parenting attitudes that were more authoritarian were related to higher expectations regarding children's family obligations between families within cultures as well as between cultures. These international findings advance understanding of children's family obligations by contextualising them both within families and across a number of diverse cultural groups in 9 countries.  相似文献   
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