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91.
A number of recent studies have explored the consequences ofinterracial peer effects on the academic and social performanceof minority students. This article contributes to that discussion,focusing, however, on perceptions rather than behaviors. Theanalysis suggests that exposure to white peers is associatedwith declining perceptions of racial justice among black andLatino high school students. While cautioning against causalinterpretations of this finding, the article suggests that theintegrationist aims of Brown v. Board of Education will notbe satisfied without more thoughtful and vigorous desegregationefforts. 相似文献
92.
Some features of early child care are more prominent in Norway than in other countries, such as emphasis on the outdoor environment. Of general relevance and interest is the form of day care provided by forest day-care centers. Three ideas form the development of these centers placed in wild areas. First, throughout history, Norwegians have had a close attachment to nature and some parents want to provide their children with outdoor experiences at an early age. Second, urging children to play outdoors characterizes the image many parents have of a happy, healthy childhood. Third, provision of day care for children has always been restricted in western countries, forcing parents to invent types of service that can become part of an ecological system that promotes healthy development.The forest day-care centers developed recently represent a supplement to the wide typology of child care in the 21st century. The article outlines the connections between these ideas in general European and western history and Norwegian history and presents debate and decisions about a question dating from the last half of the 1980s. It concludes that the forest day-care centers are perhaps only a modern form of the original kindergarten concept, which started in Europe and America as gardens for children not gardens of children. 相似文献
93.
94.
Deoxyribonucleic acid (DNA) typing of ribosomal ribonucleic acid (rRNA) genes was performed with a polymerase chain reaction (PCR) assay for species identification. A variable region of the 28S ribosomal RNA gene was amplified with primers complementary to flanking sequences phylogenetically well conserved. The products of twelve animal DNAs (human, Japanese monkey, dog, cattle, pig, cat, rabbit, mouse, rat, chicken, frog, and fish) were separated by polyacrylamide gel electrophoresis, each revealing a few bands ranging from 150 to 100 base pairs. The band patterns obtained from each DNA sample differed in number and size, which indicates the applicability of the method to species identification. Samples containing either as little as 1 pg of DNA or degraded DNA of 0.2 to 0.5 kb in length were able to give detectable bands. Postmortem human tissue DNAs were tested as an example. They showed a pattern identical to the human control one, which was distinct from those of the other animals examined. 相似文献
95.
Andrew M. Greeley is a priest, sociologist, novelist, and journalist. His scholarly writings concentrate on religion and ethnicity.
His other writings range from critiques of the Catholic church to best-selling novels. 相似文献
96.
97.
A report of an international collaborative experiment to demonstrate the uniformity obtainable using DNA profiling techniques. 总被引:2,自引:0,他引:2
P Gill S Woodroffe W B?r B Brinkmann A Carracedo B Eriksen S Jones A D Kloosterman B Ludes B Mevag 《Forensic science international》1992,53(1):29-43
This paper describes a collaborative exercise intended to demonstrate whether uniformity of DNA profile results could be achieved between different European laboratories. It was shown that this goal can be obtained provided that a common protocol is followed (specifically the use of a common electrophoretic buffer as being the most important parameter). Generally, lower molecular weight loci (with lower molecular weight fragments) such as YNH24 perform better than higher molecular weight loci such as MS43a. The results of the exercise are discussed in relation to the objectives of the European DNA profiling group (EDNAP). 相似文献
98.
N C Martin A A Pirie L V Ford C L Callaghan K McTurk D Lucy D G Scrimger 《Science & justice》2006,46(3):179-184
In the forensic science laboratory, the recovery of spermatozoa from vaginal swabs, or vaginal cells from penile swabs, can help determine if sexual intercourse may have taken place. There are several methods used to recover spermatozoa and cells from the swabs before visualisation on a microscope slide and most of these methods use water. Phosphate buffered saline (PBS) is a non-toxic solution used in many biological laboratories. Unlike water, PBS prevents cells rupturing or shrivelling up due to osmosis. This study demonstrates that PBS can be used for the extraction of spermatozoa and cells from swabs and that PBS does not affect subsequent DNA profiling. 相似文献
99.
The 2003 Duma election resulted in the victory of the party of power, thereby strengthening managed democracy in Russia. Since then, political trends in Russia's regions and rural politics provide considerable evidence of the increasing ability of pro-Kremlin forces to maximise their electoral fortunes in national contests. These political trends make it likely that United Russia will not only emerge as the dominant party in the 2007 Duma election, but will provide the Kremlin and Putin's successor with a compliant lower house. The outcome is that Putin's successor will find the political infrastructure to continue managed democracy. 相似文献
100.
Netherlands International Law Review - 相似文献