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Dendrochronology is usually the only method of precise dating of unsigned art objects made on or of wood. It has a long history of application in Europe, however in Russia such an approach is still at an infant stage, despite its cultural importance. Here we present the results of dendrochronological and radiocarbon accelerated mass spectrometry (AMS) dating of three medieval icons from the 15th–17th century that originate from the North of European Russia and are painted on wooden panels made from Scots pines. For each icon the wooden panels were dendrochronologically studied and five to six AMS dates were made. Two icons were successfully dendro-dated whereas one failed to be reliably cross-dated with the existing master tree-ring chronologies, but was dated by radiocarbon wiggle-matching. Wiggle-matching of radiocarbon dates is the most promising method for dating Russian icons in the absence of a dense dendrochronological network. However, for this case uncertainties connected with the radiocarbon method have to be taken into account and further studies of these uncertainties must be undertaken by comparing dendro-dated and radiocarbon-dated wooden works of art. Our results, moreover, showed that in two cases art-historical dates were by five to ten decades older than the earliest possible time of the creation of the icons, based on dendrochronology.  相似文献   

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Announcement

International Congress of the German Mycological Society, University Hamburg, Sept. 16th–23th 2010  相似文献   

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The 6 million French-Canadians of Québec derive from a relatively small number of founders. Consequently, some hereditary diseases, which may or may not present a worldwide distribution, have been detected in high frequency in this population. Several studies, however, indicate a nonuniform distribution of these diseases through the population, suggesting that the French-Canadian founder effect has been geographically stratified. Here we explore this stratification by using a demographic database, the Population Register of Early Québec, that contains almost all birth, marriage, and death certificates (>712,000) recorded in parish registers between 1608-1800. In this database, every genealogical link has been traced back to the founders of the population, so that we can compute the genetic contribution of founder per region, and then account for the early events that have shaped the distribution of diseases. Ten regions, comprising varying numbers of parishes, have been selected. We first describe each region in terms of homogeneity and concentration of its gene pool. For this purpose, a new concept is introduced, the founders' uniform contribution number (FUN), i.e., the number of founders a population would have if all its founders had an equal contribution. Second, we estimate genetic similarity between regions on the basis of differential genetic contribution. To classify the regions, we use principal component and cluster analysis. Our results show a tripartite clustering of the population, and invite us to reconsider the results obtained from biomolecular and clinical studies, which show a bipartite clustering.  相似文献   

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Within the framework of the Sicily Mummy Project, the orofacial complex of a significant sample of individuals (n = 111) from the Capuchin Catacombs of Palermo, Italy, was inspected. The heads and dentitions of the mummies were documented and the recorded findings described: the state of preservation of skeletal and soft tissues; dental pathologies such as carious lesions and alveolar bone loss; enamel hypoplasia; and ante- and post-mortem tooth loss. Despite limitations in data collection, the oral health of these mummies was assessed and the frequencies of pathologies were compared to those of similar populations. From their position within the corridors of the Catacombs, sex and social status of the mummies were also inferred, allowing the dental pathologies to be specified in the social and historical context. Most interestingly, the rate of oral health problems did not differ between the groups of the members of the Capuchin Order and the laymen of the city of Palermo, despite their different lifestyles.  相似文献   

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The 100th of the world’s worst invasive alien species   总被引:2,自引:0,他引:2  
Biological invasions are among the greatest threats to global biodiversity, but in contrast to most other global threats, they suffer from specific communication issues. Our paper presents the first new addition to the widely cited IUCN list of “100 of the world’s worst invasive species”, a list created a decade ago in response to these communication issues. We briefly present this list, the recent removal of one species from that list, and the rationale to include a novel, 100th species to replace it. The new species of this list, giant salvinia (Salvinia molesta), was chosen by the community of invasion biologists (over 650 experts from over 60 countries). This new addition to the list will draw public attention to the damage caused by invasive alien species and it will help stimulate the necessary discussion of this critical issue in science and policy circles.  相似文献   

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Previous research has demonstrated that consanguineous marriage is a vector for socioeconomic inheritance and for the maintenance of family structure and property. On the basis of reconstituted families from the Krummhörn, Ostfriesland in the 18th and 19th centuries, we examine statistical correlations between ascertained inbreeding coefficients (F) based on family trees and socioeconomic status as well as the intergenerational transmission of landholdings. Semiparametric copula/bivariate regression models with non-random sample selection were applied to estimate F and the proportion of medium (0.0625?>?F?≥?0.0156) or high consanguineous unions (F?≥?0.0625), respectively. Our estimates for F as well as for the proportion of medium (0.0625?>?F?≥?0.0156) or high consanguineous unions (F?≥?0.0625) are significantly higher among socioeconomically privileged large farmer families than among the landless portion of the population. At the same time, our analyses show that a high level of consanguinity is associated with an increased intergenerational transmission of landholdings through the patriline (but not the matriline). We discuss the reproductive consequences of consanguinity among large farmers in connection with local resource competition, intensive kinship, and potential in-law conflicts.  相似文献   

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Catches of whales show a historically cyclical pattern, with catches declining as stocks of the financially most attractive species fell, but expanding as substitute species were caught. Total combined catch peaked in the early 1960s and fell thereafter to the current regulated levels. While it is widely thought that international whaling agreements account for the current stable stock levels, economic analysis reveals that market forces leading to reduced catch were already in place well before the agreements took hold. To some extent, therefore, catches were destined to decline as whale products ceased to be commercially attractive on a large scale. Using econometric analysis, the paper shows the various forces at work: declining stocks, the rise of substitute products, internationally increasing environmentalism, and rising incomes. Of these forces, stock decreases, which resulted in high unit catch costs, and income growth, which reduced rather than increased demand, were the most important factors, with regulation following, rather than leading, catch changes.  相似文献   

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Age estimation of unknown skeletal remains is very important in forensic medicine. Morphologic methods are fast and easy to use for purpose of age determination. The sternal ends of the ribs are a reliable method of age estimation from late adolescence to old age. Iscan et al developed a phase analysis method for the right 4th rib that was sex and race specific. The purpose of this study is to determine the accuracy of the standards of age estimation from the right 4th and other rib using the phase analysis for the Turkish population. The sample consisted of right and left 3rd, 4th and 5th ribs from 34 Turkish women and 76 men. There were statistically significant variations found on the right 5th, left 3rd, 4th, and 5th ribs according to these standards in men for phases 5, 6, and 7. For women, all the right and left ribs included in this study were in concordance with right 4th rib standards in all phases.  相似文献   

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Marine biology and biological oceanography are two disciplinary subfields that have long struggled with their definitions. Should marine biology simply be considered a part of biology that takes place in the marine environment or is it a distinct entity, with conceptual problems and methodological approaches all its own? Similarly, biological oceanography could be seen as a necessary adjunct to physical and chemical oceanography or it could be defined more as an extension of biology into the marine realm. In the United States, these issues were directly addressed from the mid 1950s through the mid 1960s in a series of events that shed light on how marine biologists came to a working definition of their field that provided a broad methodological tent for practitioners and, at the same time, allied the field to oceanography during a period in which exploration of uncharted areas drew considerable funding from the post-WWII federal agencies charged with keeping American science at the forefront.  相似文献   

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Conclusions  When we take stock of developments in the decade since the 1992 United Nations Conference on Environment and Development in Rio de Janeiro, we see a diverse picture with hopeful and promising steps in the right direction, but also reasons to be concerned.  相似文献   

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Over the past decade, there has been much interest in the biology and diagnostic applications of cell-free nucleic acids in plasma. Research in this area started with the demonstration of tumour-derived DNA and RNA molecules in the plasma of cancer patients. My group has a longstanding interest in using this approach for the detection and monitoring of cancer common in China, including nasopharyngeal carcinoma and lung cancer. My interest has since expanded into other species of circulating nucleic acids and has led to the discovery of cell-free fetal DNA and RNA in the plasma of pregnant women. The latter has allowed the non-invasive prenatal diagnosis of a number of fetal genetic diseases and traits (e.g. RhD blood group) from maternal blood. Progress in this area has been accelerated with the development of a number of powerful analytical tools. Recent examples include microfluidics digital PCR and next-generation DNA sequencing.CBR. 2010 Nov; 31(4): S7.

S2 Point-of-Care Testing: Disruptive Technologies and Improving Health Outcomes

CP PriceAuthor information Copyright and License information DisclaimerDepartment of Clinical Biochemistry, University of Oxford, Oxford, United Kingdommoc.liamg@1ecirppcThe contents of articles or advertisements in The Clinical Biochemist – Reviews are not to be construed as official statements, evaluations or endorsements by the AACB, its official bodies or its agents. Statements of opinion in AACB publications are those of the contributors. Print Post Approved - PP255003/01665. Copyright © 2005 The Australasian Association of Clinical Biochemists Inc. No literary matter in The Clinical Biochemist – Reviews is to be reproduced, stored in a retrieval system or transmitted in any form by electronic or mechanical means, photocopying or recording, without permission. Requests to do so should be addressed to the Editor. ISSN 0159 – 8090  相似文献   

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Thyroglobulin (Tg) protein is synthesised uniquely by thyroid tissue and is measured as a post-operative differentiated thyroid cancer (DTC) tumour-marker. Tg autoantibodies (TgAb), present in ∼20 percent of DTC patients, interfere with Tg immunometric assay (IMA) measurements causing falsely low/undetectable serum Tg values. Tg radioimmunoassay (RIA) methodology appears resistant to such interferences but has limited availability, whereas new Tg mass-spectrometry methods have inferior sensitivity and unproven clinical value. When present, TgAb concentrations respond to changes in thyroid tissue mass. Thus, when Tg IMA measurements are compromised by the presence of TgAb the TgAb trend can serve as a surrogate DTC tumour-marker. Unfortunately, both physiologic and technical factors impact the interpretation of Tg and TgAb used as DTC tumour-markers.

Serum Tg Testing

Circulating Tg concentrations change in response to thyroid tissue mass, injury (surgery, biopsy or radioiodine) and the degree of TSH stimulation. Technical factors (Tg assay sensitivity, specificity and interferences) additionally impact the clinical utility of Tg testing. Specifically, new 2nd generation Tg IMAs (functional sensitivities ≤ 0.1 μg/L) now mostly obviate the need for expensive recombinant human TSH(rhTSH)-stimulated Tg testing. Tg molecular heterogeneity remains responsible for two-fold between-method differences in Tg values that preclude switching methods and TgAb interference remains especially problematic.

Serum TgAb Testing

Reliable TgAb testing is critical for authenticating that Tg IMA measurements are not compromised by interference. Unfortunately, TgAb methodologies vary widely in sensitivity, specificity and the absolute values they report, necessitating that TgAb concentrations be monitored using the same method. Furthermore, adopting the manufacturer’s TgAb cut-off value to define a ‘detectable’ TgAb results in falsely classifying sera as TgAb-negative, because manufacturers’ cut-offs are set to diagnose thyroid autoimmunity and not to detect TgAb interference.CBR. 2012 Nov; 33(4): S13.

S10 Lab Tests Online – Pathology Information for the People

B CampbellAuthor information Copyright and License information DisclaimerEditor, Lab Tests Online Australasia moc.liamg@rekwahdnallebpmacThe contents of articles or advertisements in The Clinical Biochemist – Reviews are not to be construed as official statements, evaluations or endorsements by the AACB, its official bodies or its agents. Statements of opinion in AACB publications are those of the contributors. Print Post Approved - PP255003/01665. Copyright © 2005 The Australasian Association of Clinical Biochemists Inc. No literary matter in The Clinical Biochemist – Reviews is to be reproduced, stored in a retrieval system or transmitted in any form by electronic or mechanical means, photocopying or recording, without permission. Requests to do so should be addressed to the Editor. ISSN 0159 – 8090  相似文献   

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