ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Hunter-gatherer genomic diversity suggests a southern African origin for modern humans [Genetics] (2011)
    National Academy of Sciences
    Details
    Publication Date: 2011-03-30
    Description: Africa is inferred to be the continent of origin for all modern human populations, but the details of human prehistory and evolution in Africa remain largely obscure owing to the complex histories of hundreds of distinct populations. We present data for more than 580,000 SNPs for several hunter-gatherer populations: the Hadza and Sandawe of Tanzania, and the ≠Khomani Bushmen of South Africa, including speakers of the nearly extinct N|u language. We find that African hunter-gatherer populations today remain highly differentiated, encompassing major components of variation that are not found in other African populations. Hunter-gatherer populations also tend to have the lowest levels of genome-wide linkage disequilibrium among 27 African populations. We analyzed geographic patterns of linkage disequilibrium and population differentiation, as measured by FST, in Africa. The observed patterns are consistent with an origin of modern humans in southern Africa rather than eastern Africa, as is generally assumed. Additionally, genetic variation in African hunter-gatherer populations has been significantly affected by interaction with farmers and herders over the past 5,000 y, through both severe population bottlenecks and sex-biased migration. However, African hunter-gatherer populations continue to maintain the highest levels of genetic diversity in the world.
    Keywords: Feature Articles
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    The Red Chris Porphyry Copper-Gold Deposit, Northern British Columbia, Canada: Igneous Phases, Alteration, and Controls of Mineralization (2015)
    Society of Economic Geologists (SEG)
    Details
    Publication Date: 2015-04-16
    Description: Red Chris is a Late Triassic porphyry Cu-Au-(Mo) deposit in the Stikinia island-arc terrane in northern B.C. Late Triassic sedimentary and volcanic rocks of the Stuhini Group host a series of Late Triassic to Early Jurassic (204–198 Ma) diorite to quartz monzonite stocks and dikes. The Red Chris deposit is hosted in the 204 Ma Red stock, the largest (6.5 x 1.5 km) and most altered intrusion in the area. Volcanic rocks approximately time equivalent with the stock are exposed 2 km to the southwest and west. Postmineral Early and Middle Jurassic sedimentary rocks unconformably overlie the Stuhini Group and Red stock to the south and southeast. The composite Red stock consists of multiple phases of crowded porphyries (30–65% plagioclase + hornblende ± biotite phenocrysts) including abundant premineral "P1" leucodiorite; multiple subphases of synmineral "P2" quartz monzonite porphyries; and volumetrically minor late mineral monzonite ("P3") and monzodiorite ("P4") porphyries. The stock evolved from subalkaline to silica-saturated alkalic composition, with the mineral-related P2 porphyries being high K calcalkalic and high Sr/Y. Common septa of Stuhini biotitic hornfels are entrapped within the stock. Minor postmineral, weakly altered mafic dikes cut the stock. The zone of 〉0.25% Cu equiv (Cu + Au) is 〉2 km long (WSW-ENE) and up to 650 m wide. Early A-type quartz veins with disseminated bornite accompanied biotitic and K-feldspar-magnetite alteration, which was coeval with P2 porphyries. Higher Cu and Au grades correlate in a general way with zones of more abundant A veins. Chlorite-carbonate-epidote-actinolite replaced hornblende peripheral to biotitic alteration, and chlorite overprinted much of the secondary biotite. Late alteration affected all porphyry phases and is subdivided into earlier sericite-clay-pyrite, and later low sulfide carbonate-clay-hematite. Late sericite-clay-pyrite alteration sulfidized much of the primary bornite to chalcopyrite with or without pyrite, and carbonate-clay-hematite alteration converted most magnetite to hematite. Highest Cu-Au grades (〉2% Cu equiv) occur in and around the early and intermediate stage P2 porphyries. Zoning of Cu, Au, Au/Cu ratios, sulfides, and quartz veins is centered and mostly symmetrical around a core of high-grade Cu-Au within and surrounding apices of P2 porphyry. Contact relationships confirm the close association of P2 porphyry phases with Cu-Au. Zones of 〉50 ppm Mo surround the highest grade Cu-Au zone at depth. West-northwest and east-northeast strike-slip to oblique-slip faults offset sulfide, Cu-Au, and Mo patterns. Several lines of evidence indicate 15° to 20° of southward tilt since the system formed. Due to glaciation, oxidation is very thin and supergene enrichment negligible. Red Chris was previously considered by most workers as an alkalic or "hybrid" alkalic deposit. New chemical data on synmineral porphyry phases instead suggest high K calc-alkalic composition, similar to the monzonitic Cu-(Mo-Au) class of porphyry deposits, which includes Bingham and Bajo de la Alumbrera. Red Chris is also classified as an A vein type deposit due to strong control of higher grade Cu-Au by A vein stockworks with abundant disseminated Cu sulfides.
    Print ISSN: 0361-0128
    Topics: Geosciences
    Published by Society of Economic Geologists (SEG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Pesticide resistance via transposition-mediated adaptive gene truncation in Drosophila (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-07-30
    Description: To study adaptation, it is essential to identify multiple adaptive mutations and to characterize their molecular, phenotypic, selective, and ecological consequences. Here we describe a genomic screen for adaptive insertions of transposable elements in Drosophila. Using a pilot application of this screen, we have identified an adaptive transposable element insertion, which truncates a gene and apparently generates a functional protein in the process. The insertion of this transposable element confers increased resistance to an organophosphate pesticide and has spread in D. melanogaster recently.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Aminetzach, Yael T -- Macpherson, J Michael -- Petrov, Dmitri A -- New York, N.Y. -- Science. 2005 Jul 29;309(5735):764-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biological Sciences, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16051794" target="_blank"〉PubMed〈/a〉
    Keywords: Adaptation, Physiological ; Alleles ; Amino Acid Substitution ; Animals ; Azinphosmethyl/pharmacology ; Base Sequence ; Choline/metabolism ; Crosses, Genetic ; *DNA Transposable Elements ; Drosophila/drug effects/genetics/physiology ; Drosophila Proteins/chemistry/*genetics/physiology ; Drosophila melanogaster/drug effects/*genetics/physiology ; *Evolution, Molecular ; Exons ; Female ; Gene Expression ; *Genes, Insect ; Haplotypes ; Insecticide Resistance/*genetics ; Insecticides/pharmacology ; Introns ; Long Interspersed Nucleotide Elements ; Molecular Sequence Data ; Mutation ; Polymorphism, Genetic ; Recombination, Genetic ; Selection, Genetic
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    What Are You Sampling? (1978)
    Society for Sedimentary Geology
    Details
    Publication Date: 1978-01-01
    Print ISSN: 1527-1404
    Electronic ISSN: 1938-3681
    Topics: Geosciences
    Published by Society for Sedimentary Geology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    Electronic Resource
    Electronic Resource
    Response to urbanization of the avon-heathcote estuary, christchurch, New Zealand (1979)
    Springer
    Environmental geology 3 (1979), S. 23-27 
    Details
    ISSN: 1432-0495
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The Avon-Heathcote is a small, microtidal, predominantly intertidal, weather-dominated estuary. It has experienced large alterations to its physical environment as a result of the establishment and growth the adjacent Christchurch City, on what was previously a swampy, dune-bordered coastal plain. During the first 25 years of settlement the volume of the tidal compartment of the estuary decreased from 7.7 × 106 m3 to about 5 × 106 m3. A combination of rapid drain laying in the 1880s and 1890s and the conversion of much of the catchment of the estuary to urban uses altered the sediment yields and runoff characteristics of the area and resulted in a reversal of the early trend. By 1925 the tidal compartment had returned to its original volume, and by 1975 it had reached a volume of 10.93 × 106 m3. The early decrease was accompanied by widespread deposition of a 30–60 cm thick layer of muddy sediment, some of which remains. The estuary inlet underwent major adjustments to accomodate the increasing tidal flow and now appears to be approaching a new, posturban equilibrium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02423275
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Limitations of radioactive microspheres as tracers for bone blood flow and extraction ratio studies (1980)
    Springer
    Calcified tissue international 31 (1980), S. 261-265 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; blood flow ; microspheres ; fluorine ; strontium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Radioactive microspheres have been used for measuring bone blood flow and the extraction ratios of bone-seeking radionuclides, but we have shown that the technique is not completely valid. Bone uptake of18F and85Sr was compared with that of microspheres simultaneously injected into the heart or aorta of rats and rabbits under a variety of conditions. In single-passage experiments with quick killing to avoid recirculation, attention was focused on the tibiae and femora which could be dissected quickly to avoid post-mortem migration. For the rest of the skeleton, the effect of the latter was minimized by allowing recirculation for 5 min and comparing blood flow determinations in conjunction with a cardiac output measurement. The apparent extraction ratio of18F was variable and always exceeded unity in the single-passage experiments. With recirculation, there were significant differences between the extraction ratios for some bones, and the ratios sometimes exceeded unity. Extraction ratios for85Sr were similarly variable, but lower. When85Sr was compared directly with18F, the relative extraction ratio was 0.8, with little variation between bones or animals. It is concluded that the flux of microspheres entering the vasculature of bone is not representative of blood flow, owing to the removal of some microspheres in pre-osseous capillary beds. Microspheres are therefore not a satisfactory standard for the determination of extraction ratios.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02407191
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Robotic force platform for the study of posture and stance in the quadruped (1987)
    Springer
    Medical & biological engineering & computing 25 (1987), S. 693-697 
    Details
    ISSN: 1741-0444
    Keywords: Electro-hydraulic servo ; Posture and stance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02447342
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Small, triaxial force plate (1987)
    Springer
    Medical & biological engineering & computing 25 (1987), S. 698-701 
    Details
    ISSN: 1741-0444
    Keywords: force measurement ; Three dimensions ; Transducers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02447343
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    facet.materialart.
    Unknown
    Hunter-gatherer genomic diversity suggests a southern African origin for modern humans (2011)
    National Academy of Sciences
    Details
    Publication Date: 2011-03-07
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Long-term preservation of slab signatures in the mantle inferred from hydrogen isotopes (2012)
    Springer Nature
    Details
    Publication Date: 2012-02-29
    Description: Long-term preservation of slab signatures in the mantle inferred from hydrogen isotopes Nature Geoscience 5, 224 (2012). doi:10.1038/ngeo1406 Authors: A. M. Shaw, E. H. Hauri, M. D. Behn, D. R. Hilton, C. G. Macpherson & J. M. Sinton Seismic tomographic images indicate that subducted lithosphere is transported into the deep mantle. Petrologic modelling shows that water contained in subducted slabs can be carried to depths of at least 200 km (ref.  ); however, whether the hydrated slab signature is preserved at greater depths depends on diffusion rates. Experimental studies give conflicting results on the question of hydrogen preservation. On a small scale, hydrogen equilibration with ambient mantle should be rapid, implying that the slab hydrogen signature may not be preserved in the deep mantle. However, on large scales the time required for diffusive equilibration is longer and hydrogen anomalies may persist. Here we present hydrogen and boron data from submarine volcanic glasses erupted in the Manus back-arc basin, southwestern Pacific Ocean. We find that samples with low hydrogen-isotope values also exhibit the geochemical signature of dehydrated, subducted lithosphere. Combined with additional geochemical and geophysical data, we interpret this as direct evidence for the preservation of hydrogen anomalies in an ancient slab in the mantle. Our geochemical data are consistent with experimental estimates of diffusion for the upper mantle and transition zone. We conclude that hydrogen anomalies can persist in the mantle without suffering complete diffusive equilibration over timescales of up to a billion years.
    Print ISSN: 1752-0894
    Electronic ISSN: 1752-0908
    Topics: Geosciences
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...