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1.
Larsen U  Yan S 《Social biology》2000,47(1-2):34-50
This paper analyzes the age pattern of effective fecundability from populations with no evidence of deliberate fertility control using a new convolution model of fecundability. The analysis is based on a sample of Hutterite birth histories from the mid-20th century, and birth histories of French Canadians from the 17th and 18th centuries. The main findings are as follows: 1) the level of effective fecundability is higher among the French Canadians compared to the Hutterites; 2) effective fecundability peaks at age 20 for the Hutterites, and in the early to mid-20s for the French Canadians; 3) Hutterite effective fecundability declines almost linearly from age 20 to 45, and French Canadian effective fecundability declines slowly from its peak to the early 30s, and more rapidly at older ages; and 4) the duration of postpartum amenorrhea is longer for the French Canadians than for the Hutterites. Because of the shorter periods of postpartum amenorrhea the Hutterites have about the same average number of children as the French Canadians, even though the French Canadians have higher effective fecundability.  相似文献   

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The genetic variability of 11 French pike Esox lucius populations from rivers or extensive aquaculture ponds was analysed using seven microsatellite markers. The fish stocking of eastern European pike in French rivers is widespread, so five supplementary populations from this region were also analysed. Genetic variability within the French population was small, and similar to that previously found in Europe for this species. French populations from stocked rivers and extensive farms formed a genetically homogeneous group, and did not diverge from most eastern European samples, which may reflect either ancestral polymorphism or a complete introgression of French populations by introduced stocks. Bayesian analysis of the admixture between populations enabled identification of the French populations that were likely to be affected by introduced stocks (of local or foreign origin). Three genetically distinct evolutionary branches were identified: continental Europe, Danube basin, and south‐western France. The last is a new finding in the species which needs to be further explored by comparisons with wild populations at other sites.  相似文献   

4.
Ambrosia artemisiifolia is an aggressive North American annual weed, found particularly in sunflower and corn fields. Besides its economic impact on crop yield, it represents a major health problem because of its strongly allergenic pollen. Ragweed was imported inadvertently to Europe in the 18th century and has become invasive in several countries, notably in the Rhône Valley of France. It has recently expanded in both the Provence-Alpes-Côte-d’Azur and Bourgogne regions. As first steps towards understanding the causes and mechanisms of ragweed invasion, genetic variability of French and North American populations was analysed using microsatellites. Overall genetic variability was similar in North America and in the Rhône-Alpes region, but within-population levels of genetic variability were surprisingly lower in native than in invasive French populations. French populations also exhibited lower among-population differentiation. A significant pattern of isolation by distance was detected among North American populations but not among French populations. Assignment tests and distribution of rare alleles did not point to a single origin for all French populations, nor for all individuals within populations and private alleles from different North American populations were found in the same French populations. Indeed, within all French populations, individual plants were roughly equally assigned to the different North American populations. Altogether, these results suggest that the French invasive populations include plants from a mixture of sources. Reduced diversity in populations distant from the original area of introduction indicated that ragweed range expansion probably occurred through sequential bottlenecks from the original populations, and not from subsequent new introductions.  相似文献   

5.
This article examines the relationship between self‐employment among French‐Canadians and the regional milieu. Our main argument is that self‐employment among French‐Canadians depends on the specific regional milieu. The empirical analysis is based on the public use file on individuals of the 1986 Census of Canada. Self‐employment is related to mother tongue, region, industry, occupation, income and language spoken at home. Then, the association of socio‐economic and socio‐demographic attributes with self‐employment and mother tongue in different French‐Canadian communities is examined. The relation between self‐employment, regional milieus and French‐Canadian communities is further explored using the correspondence analysis method. Results show that in addition to variations in class resources and local opportunities, a majority or minority setting influences the economic niches utilized by French entrepreneurs. Among francophone minorities, small and relatively assimilated communities are usually more entrepreneurial than major francophone concentrations. However, this relationship is not causal, and does not indicate an economic benefit associated with assimilation. Still, French‐Canadians are not a typical entrepreneurial minority that utilizes extensive informal entrepreneurial networks for economic mobility, and the political and economic struggle of French‐Canadians for advancement has not been markedly focused on entrepreneur‐ship. In fact, our results suggest that self‐employment is not a major facet of group mobilization among francophones. Entrepreneurship is perceived by the francophone establishment as an important means for long‐term economic advancement. In attempting to promote entrepreneurship, the need to utilize ethnic networks and community cohesion is greatly acknowledged. We conclude that the preservation of autonomous ethno‐linguistic identity is viewed not only as a means for economic advancement but as a major goal by itself. Hence, French‐Canadians resemble, perhaps, certain sub‐national minorities in Europe, rather than other ethnic minorities in North America. The desired relationship between self‐employment and retention of group identity does not yet prevail, among French‐Canadians, and their political and economic struggle for advancement, so far, has not been focused on entrepreneurship.  相似文献   

6.
French and Moroccan populations of the parasitoid Microctonus aethiopoides Loan were studied in the laboratory for their host selection, mating behavior, and reproductive success. The French strain, collected on Hypera postica (Gyllenhal), although capable of parasitizing and producing viable offspring on Sitona weevils, preferred Hypera weevils, its known target host. The Moroccan strain, collected on Sitona discoideus Gyllenhal, exhibited host specificity for Sitona. A partial reproductive isolation was observed between the two strains. Moroccan females mated more frequently with French males than did French females with Moroccan males. The pre-copulation time for mating pairs of opposite strains was significantly longer than that for mating pairs of the same strain. There was no significant difference in copulation time nor in larval and pupal duration between French and Moroccan strains. In summary, the French and Moroccan strains of M. aethiopoides are clearly separable by biological, behavioral, and morphometric traits and the preferred host for Hypera is the French strain and Sitona for the Moroccan strain. Consequently, geographic location and host source become important when considering this parasitoid as a potential biological control agent.  相似文献   

7.
This study aimed to characterize the linguistic interference that occurs during speech-in-speech comprehension by combining offline and online measures, which included an intelligibility task (at a −5 dB Signal-to-Noise Ratio) and 2 lexical decision tasks (at a −5 dB and 0 dB SNR) that were performed with French spoken target words. In these 3 experiments we always compared the masking effects of speech backgrounds (i.e., 4-talker babble) that were produced in the same language as the target language (i.e., French) or in unknown foreign languages (i.e., Irish and Italian) to the masking effects of corresponding non-speech backgrounds (i.e., speech-derived fluctuating noise). The fluctuating noise contained similar spectro-temporal information as babble but lacked linguistic information. At −5 dB SNR, both tasks revealed significantly divergent results between the unknown languages (i.e., Irish and Italian) with Italian and French hindering French target word identification to a similar extent, whereas Irish led to significantly better performances on these tasks. By comparing the performances obtained with speech and fluctuating noise backgrounds, we were able to evaluate the effect of each language. The intelligibility task showed a significant difference between babble and fluctuating noise for French, Irish and Italian, suggesting acoustic and linguistic effects for each language. However, the lexical decision task, which reduces the effect of post-lexical interference, appeared to be more accurate, as it only revealed a linguistic effect for French. Thus, although French and Italian had equivalent masking effects on French word identification, the nature of their interference was different. This finding suggests that the differences observed between the masking effects of Italian and Irish can be explained at an acoustic level but not at a linguistic level.  相似文献   

8.

Background

Growth charts are an essential clinical tool for evaluating a child''s health and development. The current French reference curves, published in 1979, have recently been challenged by the 2006 World Health Organization (WHO) growth charts.

Objective

To evaluate and compare the growth of French children who were born between 1981 and 2007, with the WHO growth charts and the French reference curves currently used.

Design

Anthropometric measurements from French children, who participated in 12 studies, were analyzed: 82,151 measurements were available for 27,257 children in different age groups, from birth to 18 years. We calculated and graphically compared mean z-scores based on the WHO and French curves, for height, weight and Body Mass Index (BMI) according to age and sex. The prevalence of overweight using the WHO, the French and International Obesity Task Force definitions were compared.

Results

Our population of children was on average 0.5 standard deviations taller than the French reference population, from the first month of life until puberty age. Mean z-scores for height, weight and BMI were closer to zero based on the WHO growth charts than on the French references from infancy until late adolescence, except during the first six months. These differences not related to breastfeeding rates. As expected, the prevalence of overweight depended on the reference used, and differences varied according to age.

Conclusion

The WHO growth charts may be appropriate for monitoring growth of French children, as the growth patterns in our large population of French children were closer to the WHO growth charts than to the French reference curves, from 6 months onwards. However, there were some limitations in the use of these WHO growth charts, and further investigation is needed.  相似文献   

9.
Arnold van Gennep was a leader in the field of French folklore and ethnology. His life was one of prolific publication, constant intellectual growth, and incisive criticism of the French social sciences. Yet he remained an outcast from the French academic life. From a survey of his writings and those of members of L'Année Sociologique, the lines of tension which resulted in van Gennep's exclusion from academe are traced . [Arnold van Gennep, Emile Durkheim, history of anthropology and folklore, French folklore, French sociology]  相似文献   

10.
For free‐swimming marine species like sharks, only population genetics and demographic history analyses can be used to assess population health/status as baseline population numbers are usually unknown. We investigated the population genetics of blacktip reef sharks, Carcharhinus melanopterus; one of the most abundant reef‐associated sharks and the apex predator of many shallow water reefs of the Indian and Pacific Oceans. Our sampling includes 4 widely separated locations in the Indo‐Pacific and 11 islands in French Polynesia with different levels of coastal development. Four‐teen microsatellite loci were analysed for samples from all locations and two mitochondrial DNA fragments, the control region and cytochrome b, were examined for 10 locations. For microsatellites, genetic diversity is higher for the locations in the large open systems of the Red Sea and Australia than for the fragmented habitat of the smaller islands of French Polynesia. Strong significant structure was found for distant locations with FST values as high as ~0.3, and a smaller but still significant structure is found within French Polynesia. Both mitochondrial genes show only a few mutations across the sequences with a dominant shared haplotype in French Polynesia and New Caledonia suggesting a common lineage different to that of East Australia. Demographic history analyses indicate population expansions in the Red Sea and Australia that may coincide with sea level changes after climatic events. Expansions and flat signals are indicated for French Polynesia as well as a significant recent bottleneck for Moorea, the most human‐impacted lagoon of the locations in French Polynesia.  相似文献   

11.
The study aimed at determining thrips species composition and thrips population density on French bean planted as a sole crop and as an intercrop with either sunflower, Irish potato, or baby corn, in various combinations. Field experiments were conducted in two seasons to examine: (1) thrips population development and thrips species composition over time, (2) effect of intercrops on thrips population density and natural enemies, and (3) effect of intercrops on French bean yield. The experiments were conducted at the Kenya Agricultural Research Institute, Embu, Kenya in a randomized complete block design with four replicates. The thrips population on French beans increased with time. It showed a peak at the flowering stage then started declining when the crops were nearing senescence. French beans hosted four thrips species, Megalurothrips sjostedti (Trybom), Frankliniella schultzei (Trybom), Frankliniella occidentalis (Pergande), and Hydatothrips aldolfifriderici (Karny) (all Thysanoptera: Thripidae) in order of decreasing abundance. The main thrips species on Irish potato and sunflower was F. schultzei. Baby corn hosted only Frankliniella williamsi (Hood) and Thrips pusillus (Bagnall). A monocrop of French bean hosted more thrips than a French bean intercrop mix. Thrips natural enemies such as Orius spp. and Ceranisus spp. were recorded in all crop plants but in especially high numbers on French bean and baby corn, respectively. Plots with French bean alone had about 1.4 times higher yields compared to intercropped plots of French bean with sunflower and French bean with baby corn. However, the percentage of pods that could get rejected on the market due to thrips damage was highest on plots with French bean alone (68 and 63%) and lowest on plots with French bean and baby corn (35 and 37%) in the first and second seasons, respectively. This study showed that a complex of thrips is found in the field and its composition varies with crop stage and species. Intercropping French bean with other crops compromises on French bean yield but reduces damage to the French bean pods, thereby enhancing marketable yield.  相似文献   

12.
The rate of introduction of exotic marine species has dramatically increased during the 19th and 20th centuries. Exemplifying this trend, the marine gastropod Ocinebrellus inornatus was first detected outside its native range in 1924 on the American Pacific coast, then in 1995 on the French Atlantic coast. To determine the origin of the French populations of this invasive species, we compared a French population with populations collected in Asia—the native range—and with a population collected in the United States. Analyses of mitochondrial DNA and allozyme polymorphism revealed that the French and American populations were closely related and substantially differentiated from the Asian populations. According to our results, the most likely scenario is that the source population of the French Atlantic coast populations was located in the United States. Indeed, taken altogether, the genetic structure of Asian populations, the time lag separating the introduction on the American Pacific coast from the introduction on the French Atlantic coast and the high level of genetic diversity in the two introduced areas (indicating an absence of major founder events) are hardly compatible with a scenario in which French population resulting only from primary introduction events from the native area. Finally, although similar, the French and American populations were not identical. Thus, even if the main source population of the French populations was located in the United States, the genetic structure of French populations may have been modified by cryptic and recurrent introduction events directly from Asia.  相似文献   

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14.
Drawing from a variety of nineteenth-century French travel narratives on Russia, the paper “Image (and) Nation: The Russian Exotic in Nineteenth-Century French Travel Narratives” explores the idea of nation as a cultural construction and narrative. The paper attempts to address in particular the role of ``exotic othering' in creating French national identity in the decades following the Revolution. Where post-Revolutionary France discovered a formidable political and military enemy in tsarist Russia, the French likewise viewed the continued enslavement of the Russian peasants as the example par excellence of tyrannical government. Russia thus appeared in the eyes of many a French traveler as the diametrical opposite of post-Revolutionary France founded on liberal Enlightenment ideals. In bringing to light both widely-read and lesser-known French accounts of travel to Russia, this paper suggests how a developing French national identity coalesced in part around the articulation of cultural difference from the Russian Other. Evoking the critical work of Homi K. Bhaba, Edward Said, Benedict Anderson and Lisa Lowe, the paper describes tropes of the exotic as they appear in these nineteenth-century French travel narratives on Russia and suggests how such narrative depictions of the Russian landscape, the Russian woman, and Russians in general established and reaffirmed – through an implicit cultural comparison – the idea of the French nation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
Alloantisera were produced in common Swiss and Danish swine breeds by immunization with leucocytes or skin-grafts. Out of the 126 antisera, 66 were chosen for further study based on titrations employing lymphocytes from unrelated pigs typed with French SLA antisera (Vaiman, Chardon & Renard, 1979). The 66 selected antisera and the French reagents defining 26 SLA specificities were used to type lymphocytes from 595 unrelated pigs of the common Swiss and Danish breeds. The reaction-patterns of the French, Swiss and Danish antisera were adequately correlated for the French SLA specificities Nos FJ 2, 3, 6, 7, 8, 9, 11, 14, 19, 20 and 24 and for the haplotypes FJ 15.1.18 and FJ 5.4. In addition, a cluster of correlated Danish and Swiss antisera characterized a new specificity, provisionally designated CPH 31. This specificity was frequent in the Danish Landrace pigs.
Using the reagents identified in this report, the segregation of SLA markers was studied. Back-cross families demonstrated segregation of 15 distinct SLA haplotypes of which 14 are common in French Landrace or Large White. Differences were found in haplotype frequencies in both the Swiss and the Danish Landrace and Large White breeds.  相似文献   

16.
Familial hyperchylomicronemia has reached a high prevalence in the French Canadian population of eastern Quebec. The birth places of 58 carriers identified through the birth of one affected child clustered in three regions. The genealogies of these 58 individuals showed that no founder was common to all of them. Three sets of founders were found, one for each region, with little overlapping between two regions. These results strongly suggest that more than one mutation, introduced by the French migrants in the 17th century, are segregating in the French Canadian population. Perche, a region situated between Paris and Normandy, appeared to be the most likely putative center of diffusion of at least one mutation in the lipoprotein lipase gene segregating in the modern-day French Canadian population of Quebec.  相似文献   

17.
This article explores how French psychologists understood the state of their field during the first quarter of the twentieth century, and whether they thought it was in crisis. The article begins with the Russian-born psychologist Nicolas Kostyleff and his announcement in 1911 that experimental psychology was facing a crisis. After briefly situating Kostyleff, the article examines his analysis of the troubles facing experimental psychology and his proposed solution, as well as the rather muted response his diagnosis received from the French psychological community. The optimism about the field evident in many of the accounts surveying French psychology during the early twentieth century notwithstanding, a few others did join Kostyleff in declaring that all was not well with experimental psychology. Together their pronouncements suggest that under the surface, important unresolved issues faced the French psychological community. Two are singled out: What was the proper methodology for psychology as a positive science? And what kinds of practices could claim to be objective, and in what sense? The article concludes by examining what these anxieties reveal about the type of science that French psychologists hoped to pursue.  相似文献   

18.
We carried out a soil sampling survey in September 2008 in central Cayenne, French Guiana, using molecular methods to assess the presence of the dimorphic fungus Histoplasma capsulatum. Four of the 31 samples collected (12.9?%) tested positive by PCR, with confirmation of the result by DNA sequencing. H. capsulatum is therefore present in urban environments in French Guiana. These results provide additional support for the primary prophylaxis of AIDS-related histoplasmosis in French Guiana.  相似文献   

19.
The French Ion Channel society has existed since 1989 and its main goal is to annually organize a scientific meeting. This meeting, which gathers young and senior French scientists, provides a great opportunity for the exchange and interaction among the ion channel research community. Additionally, for many years, the French ion channel meeting has attracted a significant number of scientists from different European countries, elevating the discussion of new insights and advances, as well as aiding in the establishment of collaborations. In this report, we summarize the five symposia selected for their novelty and importance in human channelopathies, neuroplasticity, ion channel regulations, intracellular ion channels and plant physiology.  相似文献   

20.
Alloantisera were produced in common Swiss and Danish swine breeds by immunization with leucocytes or skin-grafts. Out of the 126 antisera, 66 were chosen for further study based on titrations employing lymphocytes from unrelated pigs typed with French SLA antisera (Vaiman, Chardon & Renard, 1979). The 66 selected antisera and the French reagents defining 26 SLA specificities were used to type lymphocytes from 595 unrelated pigs of the common Swiss and Danish breeds. The reaction-patterns of the French, Swiss and Danish antisera were adequately correlated for the French SLA specificities Nos FJ 2, 3, 6, 7, 8, 9, 11, 14, 19, 20 and 24 and for the haplotypes FJ 15.1.18 and FJ 5.4. In addition, a cluster of correlated Danish and Swiss antisera characterized a new specificity, provisionally designated CPH 31. This specificity was frequent in the Danish Landrace pigs. Using the reagents identified in this report, the segregation of SLA markers was studied. Back-cross families demonstrated segregation of 15 distinct SLA haplotypes of which 14 are common in French Landrace or Large White. Differences were found in haplotype frequencies in both the Swiss and the Danish Landrace and Large White breeds.  相似文献   

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