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Darlu P Bloothooft G Boattini A Brouwer L Brouwer M Brunet G Chareille P Cheshire J Coates R Dräger K Desjardins B Hanks P Longley P Mandemakers K Mateos P Pettener D Useli A Manni F 《Human biology; an international record of research》2012,84(2):169-214
A recent workshop entitled "The Family Name as Socio-Cultural Feature and Genetic Metaphor: From Concepts to Methods" was held in Paris in December 2010, sponsored by the French National Centre for Scientific Research (CNRS) and by the journal Human Biology. This workshop was intended to foster a debate on questions related to the family names and to compare different multidisciplinary approaches involving geneticists, historians, geographers, sociologists and social anthropologists. This collective paper presents a collection of selected communications. 相似文献
84.
Moisander PH Cheshire LA Braddy J Calandrino ES Hoffman M Piehler MF Paerl HW 《FEMS microbiology ecology》2012,79(3):800-811
Relative fitness of three bloom-forming and potentially toxic cyanobacteria from the subtropical St. John's River, Florida was investigated under a range of nutrient conditions, during a bloom dominated by Cylindrospermopsis raciborskii. Nitrogen (N) was the primary nutrient limiting phytoplankton primary productivity and biomass. Phytoplankton biomass was also enhanced by phosphorus (P) added either alone or jointly with N, suggesting different components of the phytoplankton experienced distinct nutrient limitations. Based on quantitative PCR, the diazotrophic cyanobacteria Anabaena sp. and C.?raciborskii were responsible for the primary production response to P additions, while the nondiazotrophic Microcystis aeruginosa appeared to benefit from N released from the diazotrophs. Cylindrospermopsis raciborskii maintained high net growth rates under diazotrophic and nondiazotrophic conditions, while Anabaena sp. growth was significantly reduced under DIN enrichment. C.?raciborskii appears to be a generalist with regard to N source, a lifestyle traditionally not considered a viable ecological strategy among diazotrophs. Using facultative diazotrophy, C.?raciborskii gains a growth advantage under fluctuating DIN conditions, such as systems that are under the influence of anthropogenic N loading events. The described niche differentiation may be a key factor explaining the recent global expansion of C.?raciborskii. 相似文献
85.
DR Suresh Vamseedhar Annam K Pratibha BV Maruti Prasad 《Journal of biomedical science》2009,16(1):61-4
Background
Oxidative stress induced by the production of reactive oxygen species may play a critical role in the stimulation of HIV replication and the development of immunodeficiency. This study was conducted as there are limited and inconclusive studies on the significance of a novel early marker of oxidative stress which can reflect the total antioxidant capacity in HIV patients, 相似文献86.
Summary The relationship between the stability of soil microaggregates in water and the polysaccharide content was examined in rhizosphere and non-rhizosphere samples from a pot experiment using three soils that had grown peas, barley or grasses. The polysaccharide was oxidised and removed using 168h treatment with 0.02M periodate followed by 6h with 0.1M tetraborate. The decrease in polysaccharide content, measured as change in residual reducing sugars, was compared with the stability of soil microaggregates (ca 45m) in water, determined by a turbidimetric method.Total C, N and polysaccharide contents of rhizosphere soils were greater than those for the bulk soil, but the water stability of aggregates was not increased compared to unplanted controls. Periodate oxidation removed a large proportion (59–95%) of the polysaccharide and increased aggregated disruption, but there was no clear relationship between the two measurements. In rhizosphere soil, polysaccharides appreared to make less contribution to aggregate stability than polysaccharide in the bulk soil. The relatively small effect of rhizosphere polysaccharides is probably related to their presence as comparatively massive plant remains and debris; this contrasts with the decomposed and transformed material in the bulk soil. 相似文献
87.
Purified chloroplast tRNAs were isolated fromPisum sativum leaves and radioactively labeled at their 3′ end using tRNA nucleotidyl transferase and α32P-labeled CTP. Pea ctDNA was fragmented using a number of restriction endonucleases and hybridized with thein vitro labeled chloroplast tRNAs by DNA transfer method. Genes for tRNAs have been found to be dispersed throughout the chloroplast
genome. A closer analysis of the several hybrid regions using recombinant DNA plasmids have shown that tRNA genes are localized
in the chloroplast genome in both single and multiple arrangements. Two dimensional gel electrophoresis of total ct tRNA have
identified 36 spots. All of them have been found to hybridize withPisum sativum ctDNA. Using recombinant clones, 30 of the tRNA spots have been mapped inPisum sativum ctDNA. 相似文献
88.
Patterns in the distribution of sponge populations across the central Great Barrier Reef 总被引:2,自引:0,他引:2
Coral reef sponge populations were surveyed at two spatial scales: different depths and different reef locations across the continental shelf of the central Great Barrier Reef. The surveys were conducted on the forereef slopes of 12 reefs from land-influenced, inner-shelf reefs to those in the oligotrophic waters of the Coral Sea. Few sponges occur in shallow waters and the largest populations are found between 10 and 30 m depth. Sponges are apparently excluded from shallow waters because of excessive turbulence and possibly by high levels of damaging light. Sponge biomass is highest on the innershelf reefs and decreases away from the coast, whereas abundance is generally higher on middle-shelf reefs. There are considerable overlaps in the species composition on middle-, outer-shelf and Coral Sea reefs, but those on inner-shelf reefs are significantly different. The nature and size of sponge populations reflect environmental conditions across the continental shelf. The larger inner-shelf populations probably reflect higher levels of organic and inorganic nutrients and reduced amounts of physical turbulence, whereas sponges on reefs further from shore may be able to resist greater turbulence but appear more sensitive to the effects of fine sediments. These latter populations are smaller, reflecting the reduced availability of organic matter, however, many of these sponges rely on cyanobacterial symbionts to augment nutrition in these clearer, more oligotrophic waters.Contribution no. 487 from the Australian Institute of Marine Science 相似文献
89.
Interaction of Tumor Necrosis Factor Receptor-Associated Factor Signaling Proteins with the Latent Membrane Protein 1 PXQXT Motif Is Essential for Induction of Epidermal Growth Factor Receptor Expression 总被引:6,自引:1,他引:5 下载免费PDF全文
William E. Miller Jeanette L. Cheshire Nancy Raab-Traub 《Molecular and cellular biology》1998,18(5):2835-2844
90.
DR. JOHN LEE 《The Journal of eukaryotic microbiology》1993,40(4):395-410
ABSTRACT. Many advances have been made in our knowledge of the biology of foraminifera over the past several decades. Fine structural, biophysical, and molecular biological studies have shown that the most prominent components of their distinctive bidirectional granuloreliculopods are bundles of micro tubules linked by crossbridges to each other, as well as to membrane-bound organelles and the plasma membrane. the microtubules ratchet past each other as dynein transduces the free energy of ATP to produce pseudopodal movements. In spite of the fact that there are over 40,000 described species of living and fossil species of foraminifera, there have been many recent exciting discoveries of new species and groups. New casting techniques are providing us with greater understanding of the complexities and functional aspects of form in the group. Significant advances are being made in understanding the distribution and energetics of deep-sea forms. Larger and planktonic foraminifera are the hosts for a particularly diverse range of endosymbiotic algae, including dinoflagellates, chlorophytes, unicellular rhodophytes, and diatoms. Chloroplast husbandry also occurs. Significant research effort has been expended yielding us considerable insight into various aspects of the endosymbiotic phenomenon. A unified conceptual framework has been drawn to help us understand the life cycle options found in foraminifera. 相似文献