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1.
Higher levels of serum progesterone on the 20th or 23rd day following impregnation were indicative of establishment of pregnancy in buffaloes. Buffaloes with serum progesterone levels of 1 ng/ml or more on these days were taken as pregnant. The accuracy of this test for diagnosing pregnancy was 75% on the 20th and 83.3% on the 23rd day after artificial insemination. The non-pregnancy diagnosis by this test was 100% accurate on both days of the test. Subclinical endometritis and/or early embryonic deaths seem to interfere with the exact diagnosis of pregnancy.  相似文献   

2.
The establishment of Jewish communities in the territory of contemporary Portugal is archaeologically documented since the 3rd century CE, but their settlement in Trás‐os‐Montes (NE Portugal) has not been proved before the 12th century. The Decree of Expulsion followed by the establishment of the Inquisition, both around the beginning of the 16th century, accounted for a significant exodus, as well as the establishment of crypto‐Jewish communities. Previous Y chromosome studies have shown that different Jewish communities share a common origin in the Near East, although they can be quite heterogeneous as a consequence of genetic drift and different levels of admixture with their respective host populations. To characterize the genetic composition of the Portuguese Jewish communities from Trás‐os‐Montes, we have examined 57 unrelated Jewish males, with a high‐resolution Y‐chromosome typing strategy, comprising 16 STRs and 23 SNPs. A high lineage diversity was found, at both haplotype and haplogroup levels (98.74 and 82.83%, respectively), demonstrating the absence of either strong drift or founder effects. A deeper and more detailed investigation is required to clarify how these communities avoided the expected inbreeding caused by over four centuries of religious repression. Concerning haplogroup lineages, we detected some admixture with the Western European non‐Jewish populations (R1b1b2‐M269, ~28%), along with a strong ancestral component reflecting their origin in the Middle East [J1(xJ1a‐M267), ~12%; J2‐M172, ~25%; T‐M70, ~16%] and in consequence Trás‐os‐Montes Jews were found to be more closely related with other Jewish groups, rather than with the Portuguese non‐Jewish population. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

3.
Ella Butler 《Ethnos》2013,78(3):229-251
In contemporary American public culture, interest groups increasingly mobilise social constructionist arguments in order to discredit strains of scientific knowledge. According to Latour [2004. Why Has Critique Run out of Steam? From Matters of Fact to Matters of Concern. Critical Inquiry, 30:225–48], the field of science studies has contributed to this trend by exposing the ways that scientific facts are socially mediated. In this article, I examine how a narrative of social construction is articulated in the Creation Museum, a young earth creationist museum in Northern Kentucky, USA. I compare the epistemology of science in the Creation Museum with that of conspiracy theory and of social constructionist science studies. I examine how, in the Creation Museum, social constructionist critique is combined with a framing of the Bible as a source of factual data. It is argued that science studies, conspiracy theory and creationism overlap in their critiques of the transparency and objectivity of science. However, they diverge in terms of the degree of recursivity they allow.  相似文献   

4.
Population thinking and tree thinking in systematics   总被引:10,自引:0,他引:10  
Two new modes of thinking have spread through systematics in the twentieth century. Both have deep historical roots, but they have been widely accepted only during this century. Population thinking overtook the field in the early part of the century, culminating in the full development of population systematics in the 1930s and 1940s, and the subsequent growth of the entire field of population biology. Population thinking rejects the idea that each species has a natural type (as the earlier essentialist view had assumed), and instead sees every species as a varying population of interbreeding individuals. Tree thinking has spread through the field since the 1960s with the development of phylogenetic systematics. Tree thinking recognizes that species are not independent replicates within a class (as earlier group thinkers had tended to see them), but are instead inter-connected parts of an evolutionary tree. It lays emphasis on the explanation of evolutionary events in the context of a tree, rather than on the states exhibited by collections of species, and it sees evolutionary history as a story of divergence rather than a story of development. Just as population thinking gave rise to the new field of population biology, so tree thinking is giving rise to the new field of phylogenetic biology.  相似文献   

5.
In this ( Nuffield Council on Bioethics 2002) , the third in its series on ethics and related issues in genetics (see also Nuffield Council on Bioethics 1993 and Nuffield Council on Bioethics 1998) , the Nuffield Council has focused on four 'normal' behaviors; intelligence, personality, antisocial behavior and sexual orientation. This is a narrow range of behaviors and one where their discussion of the potential impact of predictive genetic testing is probably inappropriate. They also take an unduly narrow view of the purposes of behavior genetics in the 21st century. It is not simply to estimate heritability but to understand more about the structure of behavior and the processes which underlie it. Their narrow focus and their negative approach to the history and achievements of genetics is reflected in their less than positive support for future behavior genetic research. Behavior geneticists need to do more to publicize what their field has achieved in order to counter the very extensive antibehavior genetics initiatives which are almost unique in science. At the same time, organizations such as the Nuffield Council need to consider carefully the impact their deliberations may have on research funding.  相似文献   

6.
This special issue of the Cytokine and Growth Factors Review is devoted to highlighting the exceptional science that was presented at the 14th International TNF Conference held in Québec City, Canada from July 7th to July 10th, 2013. In this beautiful and historic city, approximately 175 delegates gathered to hear and present the latest advances in the TNF superfamily (TNFSF) field across broad subjects such as cancer, signal transduction, tissue homeostasis, cell death and immunity. The science presented in oral and poster format was of the highest caliber, with exciting new stories “breaking” in this exciting inter-disciplinary area of research. We await with anticipation the next (15th) International TNF Conference to be held May 20–23rd, 2015 in Ghent, Belgium. Until then, À Bientôt!.  相似文献   

7.
As expected, since we recently celebrated the 250th anniversary of birth of Wolfgang Amadeus Mozart, there has been again a renewal of interest in his short but intensive life, as well as in the true reason of his untimely dead. Mozart lived and died in time when the medical knowledge was based mostly on subjective observations, without the established basics of standardized medical terminology and methodology. This leaves a great space for hypothesizing about his health problems, as well as about the cause of his death. The medical academic community attributed to Mozart approximately 150 different medical diagnoses. There is much speculation on the possible causes of Mozart's death: uremia, infection, rheumatic fever, trichinellosis, etc. Recently some authors have raised the question about a possible concomitant neurological disease. According to available records, Mozart has shown some elements of cyclotimic disorder, epilepsy and Gilles de la Tourette syndrome. Furthermore, the finding of a temporal fracture on (allegedly) Mozart's skull, gives a way to speculations about the possibility of a chronic subdural hematoma and its compressive effect on the temporal lobe. Despite numerous theories on Mozart's pathography that also include a concomitant neurological disorder, the medical and history records about Mozart's health status indicate that he probably had suffered from an infective illness, followed most likely by the reactivation of rheumatic fever, which was followed by strong immunologic reaction in the last days of his life. Taking all the above into consideration, it is reasonably to conclude that Mozart's neurological disturbances were caused by the intensity of the infective disease, and not primarily by a neurological disease.  相似文献   

8.
There is no sharp dividing line between science and philosophy, but philosophical problems tend to have three special features. First, they tend to concern large frameworks rather than specific questions within the framework. Second, they are questions for which there is no generally accepted method of solution. And third they tend to involve conceptual issues. For these reasons a philosophical problem such as the nature of life can become a scientific problem if it is put into a shape where it admits of scientific resolution. Philosophy in the 20th century was characterized by a concern with logic and language, which is markedly different from the concerns of earlier centuries of philosophy. However, it shared with the European philosophical tradition since the 17th century an excessive concern with issues in the theory of knowledge and with scepticism. As the century ends, we can see that scepticism no longer occupies centre stage, and this enables us to have a more constructive approach to philosophical problems than was possible for earlier generations. This situation is somewhat analogous to the shift from the sceptical concerns of Socrates and Plato to the constructive philosophical enterprise of Aristotle. With that in mind, we can discuss the prospects for the following six philosophical areas: (1) the traditional mind-body problem; (ii) the philosophy of mind and cognitive science; (iii) the philosophy of language; (iv) the philosophy of society; (v) ethics and practical reasons; (vi) the philosophy of science. The general theme of these investigations, I believe, is that the appraisal of the true significance of issues in the philosophy of knowledge enables us to have a more constructive account of various other philosophical problems than has typically been possible for the past three centuries.  相似文献   

9.
L R Kass 《In vitro》1981,17(12):1091-1099
Modern science, dedicated since its 17th century origins to the mastery and possession of nature for the relief of man's estate, is a source of great social change, affecting our opinions, practices, and ways of life. It thus exists necessarily in tension with law and morality, our institutions of stability and order. This tension between change and permanence, between science and law or morals, was institutionalized by the American Founders who sought to encourage, under law, the progress in science and the useful arts, by means of the copyright and patent laws. American science and technology have flourished under the patent law, an ingenious ethical and social contract between scientists and the polity, through which private right and interest and public good generally coincide. Nevertheless, this contract has its limitations. Some of these limitations are vividly seen through the recent Supreme Court decision (in the Chakrabarty case) to permit the patenting of living microorganisms. Analysis of this case shows why the contract between science and the polity embodied in the Patent Laws may not always serve the public good and may also be harmful to science itself. Also, permitting ownership of living species shows how close we have come in our thinking to overstepping the sensible limits of the project for the mastery and possession of nature.  相似文献   

10.
Approaching science by considering the epistemological virtues which scientists see as constitutive of good science, and the way these virtues trade-off against one another, makes it possible to capture action that may be lost by approaches which focus on either the theoretical or institutional level. Following Wimsatt (1984) I use the notion of heuristics and biases to help explore a case study from the history of biology. Early in the 20th century, mutation theorists and natural historians fought over the role that isolation plays in evolution. This debate was principally about whether replication was the central scientific virtue (and hence the ultimate goal of science to replace non-experimental evidence with experimental evidence) or whether consilience of inductions was the central virtue (and hence, as many kinds of evidence as possible should be pursued).  相似文献   

11.
油瓜Hodgsonia macrocarpa,葫芦科多年生木质藤本植物。自20世纪初其食用价值被发现以来,各国科学家对其油脂组成、栽培利用进行了广泛研究。而油瓜的民族植物学系统研究则鲜为报道。本文运用关键人物访谈、小组讨论等民族植物学方法对油瓜的传统知识进行深入调查。本研究对西双版纳地区23个村寨的8个民族进行多次野外调查,记录民间传统利用数据,采集凭证标本。调查结果显示,油瓜的民族民间名多样;烤熟后的种仁被各民族所喜食;油瓜的根、茎、叶、果皮、种仁均可入药,主要用于肠道类疾病与皮肤类疾病的治疗。当地名称的多样性反映了各民族认识油瓜角度的差异,各民族间在油瓜食用知识方面较为一致,在药用知识上具在一定的差异。  相似文献   

12.
Hodgsonia macrocarpa, commonly known as lardfruit, is a perennial woody vine belongs to family Cucurbitaceae. Since the food value of its kernel was reported in the early 20th century, increasing studies have been focused on the introduction and cultivation of the wild populations and chemical analysis of the edible kernel oils. While its ethnobotanical details about local nomenclaetures, gathering techniques, form of consumption and folk resouce management are left unclear. In this study we collected these ethnobotanical data from 8 ethnic groups by conducting field survey in 23 ethnic villages in Xishuangbana. Methods including key informants interview and group discussion were used for recording the traditional medicinal and culinary knowledge of lardfruit. The results show an unexpected diversity of their folk names, which indicate the long history of folk uses. The baked edible kernel is favored by all the 8 ethnic groups. The root, stem, leaf, fruit and seed are widely used as herbal medicine for the treatment of intestinal diseases and skin ailments. The diverse folk names and multiple medicinal uses practice among different ethnic groups indicate that they exploited this plant resource in various perspectives for culture, economic and social reasons.  相似文献   

13.
Infant and child mortality in 18th and 19th century Krummhörn exhibits a remarkable feature: significantly more daughters than sons of comparably prosperous high status farmers achieve adulthood. We interpret this difference as being the outcome of differential parental care reflecting varying reproductive perspectives and social role expectations, to which sons and daughters from farmer families were exposed. This is verified by sex differences in the children's probability of marrying and their differing chances of social persistence. Against the background of severely restricted reproductive opportunities and recognizably higher upbringing costs for a son, parental underinvestment in the survival of sons can be best understood as an economically motivated measure in the course of a farmer's efforts to concentrate his property and to maintain his family's social status. At the same time, such a scenario also had a biological adaptive value, because it contributed to the intergenerational perpetuation of above average chances of life and reproduction, and hence, to the genetic persistence of the farmer families.  相似文献   

14.
An effective bibliometric analysis based on the Science Citation Index (SCI) published by the Institute of Scientific Information (ISI) was carried out to identify wetland research between 1991 and 2008. The objective was to conduct a quantitative and qualitative analysis for global trends of wetland-related research. The characteristics related to publications were analyzed. The results showed the significant wetland research issues in the SCI database. From 1991 to 2008, the annual number of journal articles published and the number of articles cited to wetland research increased more than sixfold and ninefold respectively. The USA produced the most single-country articles and international collaborative articles, followed by Canada and UK. The results also showed the significant wetland research issues in SCI database. The most frequently used words were: “water” (or “water quality”), which ranked 3rd, 7th, and 3rd according to the word in article title, author keyword, and keyword plus analysis, respectively. Constructed wetland biodiversity became more active in wetland research. The keywords “constructed wetland” and “constructed wetlands” ranked 58th and 12th in 1991–1996, while they ranked 5th and 4th in 2003–2008; the author keyword “biodiversity” ranked 45th in 1991–1996, while it ranked 23rd in 1997–2002, and 14th in 2003–2008; and keyword plus “diversity” ranked 93rd in 1991–1996, while it ranked 20th in 1997–2002, and 17th in 2003–2008. Moreover, it was proved that article title, author keyword, and keyword plus analysis methods were effective approaches for mapping wetland research. Popular wetland research issues and wetland research changes were also identified by statistical analysis.  相似文献   

15.
The Yakuts, Middle Age Turkic speakers (15th-16th centuries), are widely accepted as the first settlers of the Altai-Baikal area in eastern Siberia. They are supposed to have introduced horses and developed metallurgy in this geographic area during the 15th or 16th century A.D. The analysis of the Siberian grave of Pokrovsk, recently discovered near the Lena River (61 degrees 29' N) and dated by accelerator mass spectrometry from 2,400 to 2,200 years B.P., may provide new elements to test this hypothesis. The exceptional combination of various artifacts and the mitochondrial DNA data extracted from the bone remains of the Pokrovsk man might prove the existence of previous contacts between autochthonous hunters of Oriental Siberia and the nomadic horse breeders from the Altai-Baikal area (Mongolia and Buryatia). Indeed, the stone arrowhead and the harpoons relate this Pokrovsk man to the traditional hunters of the Taiga. Some artifacts made of horse bone and the pieces of armor, however, are related to the tribes of Mongolia and Buryatia of the Xiongnu period (3rd century B.C.). This affinity has been confirmed by the match of the mitochondrial haplotype of this subject with a woman of the Egyin Gol necropolis (Mongolia, 2nd/3rd century A.D.) as well as with two modern Buryats. This result allows us to postulate that contacts between southern steppe populations and Siberian tribes occurred before the 15th century.  相似文献   

16.
ABSTRACT

Proteome—the protein complement of a genome—has become the protein renaissance and a key research tool in the post-genomic era. The basic technology involves the routine usage of gel electrophoresis and spectrometry procedures for deciphering the primary protein sequence/structure as well as knowing certain unique post-translational modifications that a particular protein has undergone to perform a specific function in the cell. However, the recent advancements in protein analysis have ushered this science to provide deeper, bigger and more valuable perspectives regarding performance of subtle protein-protein interactions. Applications of this branch of molecular biology are as vast as the subject is and include clinical diagnostics, pharmaceutical and biotechnological industries. The 21st century hails the use of products, procedures and advancements of this science as finer touches required for the grooming of fast-paced technology.  相似文献   

17.
18.
Proteome--the protein complement of a genome--has become the protein renaissance and a key research tool in the post-genomic era. The basic technology involves the routine usage of gel electrophoresis and spectrometry procedures for deciphering the primary protein sequence/structure as well as knowing certain unique post-translational modifications that a particular protein has undergone to perform a specific function in the cell. However, the recent advancements in protein analysis have ushered this science to provide deeper, bigger and more valuable perspectives regarding performance of subtle protein-protein interactions. Applications of this branch of molecular biology are as vast as the subject is and include clinical diagnostics, pharmaceutical and biotechnological industries. The 21st century hails the use of products, procedures and advancements of this science as finer touches required for the grooming of fast-paced technology.  相似文献   

19.
Analysis of the skeletal contents of this random collection of cremation urns provides some very interesting general observations (see Table 1, below). The remains of as many as 19 people have been identified, although fewer actually may be present (e.g., see 875 and 876). Two of these 19 are infants, ages 1 and 3, and a third may be a child of 11 years. Where sex can be identified, ten of the “adults” appear to be females, and only 5 are identified as males. The high proportion of females may be explained by the kinds of cinerary containers here reviewed. The relatively simple urns which are represented in this selection of cinerary containers are typical of those used for women, reflecting the relatively low status of women in the ancient world. Also of note is the fact that 4 of the females were between 17 and 22.5 years of age at death, and another 2 may have been about 25 years at death. This suggests that many women were dying in childbirth. The diverse origins of these vessels prevents us from reaching any specific conclusions regarding their use, but the high proportion of young adult women suggests that they had been married, and probably that they died in childbirth before having achieved high status as the mother of grown children. Therefore, these women received relatively low status interments in inexpensive containers which probably were placed among the more elaborate sarcophagi and other containers in upper class tombs. These were the target of excavations during the 19th and early 20th century.  相似文献   

20.
The discipline of functional morphology grew out of a comparativeanatomical tradition, its transformation into a modern experimentalscience facilitated largely by technological advances. Earlymorphologists, such as Cuvier, felt that function was predictablefrom organismal form, to the extent that animals and plantsrepresented perfect adaptations to their habits. However, anatomyalone could not reveal how organisms actually performed theiractivities. Recording techniques capable of capturing fast motionwere first required to begin to understand animal movement.Muybridge is most famous for his pioneering work in fast photographyin the late 19th century, enabling him to "freeze" images ofeven the fastest horse at a full gallop. In fact, contemporarykinematic analysis grew directly out of the techniques Muybridgedeveloped. Marey made perhaps an even greater contribution toexperimental science through his invention of automatic apparatifor recording events of animal motion. Over the first half ofthe 20th century, scientists developed practical methods torecord activity patterns from muscles of a living, behavinghuman or animal. The technique of electromyography, initiallyused in clinical applications, was co-opted as a tool of organismalbiologists in the late 1960s. Comparative anatomy, kinematicanalysis and electromyography have for many years been the mainstayof vertebrate functional morphology; however, those interestedin animal form and function have recently begun branching outto incorporate approaches from experimental biomechanics andother disciplines (see accompanying symposium papers), and functionalmorphology now stands at the threshold of becoming a truly integrative,central field in organismal biology.  相似文献   

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