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2.
Millions of observations are available on the height of men who participated in the so-called "Forth Registration" of the United States Selective Service Administration in World war II. The men were born between April 28, 1877 and February 16, 1897.  相似文献   

3.
Within the course of the 20th century the American population went through a virtual metamorphosis from being the tallest in the world, to being among the most overweight. The American height advantage over Western and Northern Europeans was between 3 and 9 cm in mid-19th century, and Americans tended to be underweight. However, today, the exact opposite is the case as the Dutch, Swedes, and Norwegians are the tallest, and the Danes, British and Germans--even the East-Germans--are also taller, towering over the Americans by as much as 3-7 cm. Americans also have shorter lives. The hypothesis is worth considering that this adverse development is related to the greater social inequality, an inferior health care system, and fewer social safety nets in the United States than in Western and Northern Europe, in spite of higher per capita income. The Western and Northern European welfare states, with cradle to grave health and unemployment insurance currently seems to provide a more propitious environment for the biological standard of living than its US counterpart.  相似文献   

4.
This paper proposes a new understanding of race as an artifact constructed from racist violence and the trauma it engenders. The paper applies Jeffrey Alexander's concept of ‘cultural trauma’, i.e. when ‘members of a collectivity feel they have been subjected to a horrendous event that leaves indelible marks on their group consciousness’, to the case of Korean immigrant merchants who were victims of violence during the 1992 L.A. riots/insurrection/saigu in Los Angeles, California, following the acquittal of four white police officers charged with violently assaulting a black motorist. Though the violence was contained to distinct neighbourhoods, the larger society experienced the terror because of the mass media. Over time this media-event led to the construction of a new identity rooted in violence and trauma. Through an examination of various texts, this paper argues that the Korean-American collective consciousness shifted discursively from an identity rooted in nationality to one incorporating race.  相似文献   

5.
 Significant geographic partitioning of genetic variation within Cochlearia bavarica was found within populations from Allg?u and SE Bavaria (Germany) exhibiting significant genetic differentiation. It has been demonstrated that allohexaploid C. bavarica evolved via hybridization between diploid C. pyrenaica and tetraploid C. officinalis. Presently, only C. pyrenaica is distributed throughout inland Central Europe. It has been concluded that C. bavarica is of inter- or postglacial origin, and its speciation was not influenced by human activities. Isozyme analysis revealed that there is a correlation between interpopulational genetic distances and geographic distances among C. bavarica populations from both regions, and which is not the case for C. pyrenaica in Germany and Austria. Only high alpine C. excelsa is significantly differentiated among the diploid taxa analysed here. Geographically structured distribution of alleles and their frequencies in C. bavarica populations could not be explained with the distribution of these alleles in C. pyrenaica. The presented findings favour disruption of a former wider distribution area rather than migration of C. bavarica or a polytopic origin of this species. Received April 17, 2001 Accepted February 1, 2002  相似文献   

6.
Experiments were performed to test for nutrient-specific olfactory learning in the American cockroach, Periplaneta americana L. In a conditioning period, cockroaches were presented with two complementary foods, one of which contained protein and the other carbohydrate, this combination allowing them to select a nutritionally balanced diet. The foods were separated in space, and each was paired with one of two odors, citral or carvone. The cockroaches were then selectively deprived of one of the nutrients for 24 or 48 h. In the final (test) phase of the experiment the movement of the cockroaches toward the nutrient-associated odors was monitored. Associative learning was demonstrated with respect to protein, with protein-deprived cockroaches moving more frequently toward the protein-associated odor. No learned associations between carbohydrate and odor were demonstrated. These data are contrasted with similar experiments on an herbivorous insect, the locust Locusta migratoria.  相似文献   

7.
For the transfer of genes from B. tournefortii (TT) to the allotetraploid oilseed brassicas, B. juncea AABB, B. carinata BBCC and B. napus AACC, B. tournefortii was first crossed with the three basic diploid species, B. campestris (AA), B. nigra (BE) and B. oleracea (CC), to produce the allodiploids TA, TB and TC. These were tetraploidized by colchicine treatment to produce the allotetraploids TTAA, TTBB and TTCC, which were further crossed with B. juncea and B. napus to produce three-genome hybrids with substitution-type genomic configurations: TACC, TBAA and TCAA. These hybrids along with another hybrid TCBB produced earlier, the three allodiploids, their allotetraploids and the four diploid parent species were studied for their male meiotic behaviour. The diploid parent and the allotetraploids (TTAA, TTBB and TTCC) showed regular meiosis although the pollen viability was generally low in the allotetraploids. In the allodiploids (TA, TB and TC) only some end-to-end associations were observed without any clearly discernible chiasmata or exchange points. Chromosomes involved in end-to-end associations were randomly distributed at the metaphase/anaphase-I stages. In contrast, the three-genome hybrids (TACC, TBAA, TCAA and TCBB) showed normal bivalents whose number exceeded the expected bivalent values. Bivalents arising out of homoeologous pairing were indistinguishable from normal pairs by their disjunction pattern but could be distinguished on the basis of the heteromorphy of the homoeologous chromosomes. The three-genome hybrids could be backcrossed to allotetraploid oilseed brassicas as they had some fertility. In contrast, the allodiploids could neither be selfed nor back-crossed. On the basis of their meiotic stability, in terms of more pronounced homoeologous pairing and fertility for backcrossing, the three-genome configurations provide the best possible situation for the introgression of alien genes from the secondary gene pool to the allotetraploid oilseed crops B. juncea, B. napus and B. carinata.  相似文献   

8.
American lobsters (Homarus americanus H. Milne Edwards, 1837) are imported live to Europe and should according regulations be kept in land-based tanks until sold. In spite of the strict regulations aimed specifically at preventing the introduction of this species into the NE Atlantic, several specimens of H. americanus have been captured in the wild, especially in Oslofjord, Norway since 1999. One of the great concerns is interbreeding between the introduced American species and the local European lobster, H. gammarus (Linnaeus, 1758). For this reason an awareness campaign was launched in 2000 focusing on morphologically “unusual” lobsters caught in local waters. Morphological characters have been based on colour and sub-ventral spines on the rostrum. Two samples of H. americanus were used for comparisons, as well as samples of European lobster from Oslofjord collected in 1992. Previous genetic analyses (allozymes, mtDNA and microsatellite DNA) have demonstrated that the American lobster is distinct from its European counterpart, with several additional alleles at many loci in addition to different allelic frequency distribution of alleles of “shared” alleles. During the present study, thirteen microsatellite loci were tested in the initial screening, and the three most discriminating loci (Hgam98, Hgam197b and Hgam47b) were used in a detailed comparison between the two species. A total of 45 unusual lobsters were reported captured from Ålesund (west) to Oslofjord (southeast) from 2001 to 2005 and these were analysed for the three microsatellite loci. Nine specimens were identified as American lobsters. Comparisons between morphological and genetic characteristics revealed that morphological differences are not reliable in discrimination the two species, or to identify hybrids. Further, some loci display almost no overlapping in allele frequency distribution for the reference samples analysed, thus providing a reliable tool to identify hybrids.  相似文献   

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