5,032 research outputs found

    Fueling Incubation: Differential Use of Body Stores in Arctic and Temperate-breeding Barnacle Geese (Branta leucopsis)

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    We compared the use of body stores in breeding Barnacle Geese (Branta leucopsis) in traditional Arctic colonies in the Barents Sea with that in recently established temperate-zone breeding colonies in the Baltic Sea and North Sea by studying female body-mass loss and use of fat and protein stores during incubation. Average daily body-mass loss was almost identical in the 2 temperate-breeding populations (17.0 g and 16.5 g in Baltic Sea and North Sea, respectively), whereas Arctic-breeding females lost significantly less (10.6 g day-1). Temperate-breeding females initiated incubation with body mass 125 g higher than that of Arctic breeders, but at the end of incubation, body mass was similar among the 3 populations, averaging 1,458 g. Body-mass loss during incubation amounted to 23% (North Sea), 22% (Baltic Sea), and 15% (Barents Sea). Fat mass, as measured by isotope dilution in a subsample of females, was consistently higher in North Sea than in Barents Sea birds, but both populations showed similar rates of fat-mass loss (9.4 g day-1, on average). By contrast, loss of fat-free mass (assumed to represent wet protein) amounted to 9.3 g day-1 in North Sea birds but only 1.5 g day-1 in Barents Sea birds. Energy content of 1 g utilized body mass was 21.1 kJ (North Sea) and 34.9 kJ (Barents Sea), which equates to 376 kJ day-1 and 415 kJ day-1 drawn from stored energy, respectively. We suggest that differences in nest-attendance and post-incubation demands are responsible for the differential use of body stores in temperate- and Arctic-breeding Barnacle Geese.

    The NASA Astrophysics Data System: Data Holdings

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    Since its inception in 1993, the ADS Abstract Service has become an indispensable research tool for astronomers and astrophysicists worldwide. In those seven years, much effort has been directed toward improving both the quantity and the quality of references in the database. From the original database of approximately 160,000 astronomy abstracts, our dataset has grown almost tenfold to approximately 1.5 million references covering astronomy, astrophysics, planetary sciences, physics, optics, and engineering. We collect and standardize data from approximately 200 journals and present the resulting information in a uniform, coherent manner. With the cooperation of journal publishers worldwide, we have been able to place scans of full journal articles on-line back to the first volumes of many astronomical journals, and we are able to link to current version of articles, abstracts, and datasets for essentially all of the current astronomy literature. The trend toward electronic publishing in the field, the use of electronic submission of abstracts for journal articles and conference proceedings, and the increasingly prominent use of the World Wide Web to disseminate information have enabled the ADS to build a database unparalleled in other disciplines. The ADS can be accessed at http://adswww.harvard.eduComment: 24 pages, 1 figure, 6 tables, 3 appendice

    The NASA Astrophysics Data System: Architecture

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    The powerful discovery capabilities available in the ADS bibliographic services are possible thanks to the design of a flexible search and retrieval system based on a relational database model. Bibliographic records are stored as a corpus of structured documents containing fielded data and metadata, while discipline-specific knowledge is segregated in a set of files independent of the bibliographic data itself. The creation and management of links to both internal and external resources associated with each bibliography in the database is made possible by representing them as a set of document properties and their attributes. To improve global access to the ADS data holdings, a number of mirror sites have been created by cloning the database contents and software on a variety of hardware and software platforms. The procedures used to create and manage the database and its mirrors have been written as a set of scripts that can be run in either an interactive or unsupervised fashion. The ADS can be accessed at http://adswww.harvard.eduComment: 25 pages, 8 figures, 3 table

    The NASA Astrophysics Data System: The Search Engine and its User Interface

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    The ADS Abstract and Article Services provide access to the astronomical literature through the World Wide Web (WWW). The forms based user interface provides access to sophisticated searching capabilities that allow our users to find references in the fields of Astronomy, Physics/Geophysics, and astronomical Instrumentation and Engineering. The returned information includes links to other on-line information sources, creating an extensive astronomical digital library. Other interfaces to the ADS databases provide direct access to the ADS data to allow developers of other data systems to integrate our data into their system. The search engine is a custom-built software system that is specifically tailored to search astronomical references. It includes an extensive synonym list that contains discipline specific knowledge about search term equivalences. Search request logs show the usage pattern of the various search system capabilities. Access logs show the world-wide distribution of ADS users. The ADS can be accessed at http://adswww.harvard.eduComment: 23 pages, 18 figures, 11 table

    The NASA Astrophysics Data System: Overview

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    The NASA Astrophysics Data System Abstract Service has become a key component of astronomical research. It provides bibliographic information daily, or near daily, to a majority of astronomical researchers worldwide. We describe the history of the development of the system and its current status. We show several examples of how to use the ADS, and we show how ADS use has increased as a function of time. Currently it is still increasing exponentially, with a doubling time for number of queries of 17 months. Using the ADS logs we make the first detailed model of how scientific journals are read as a function of time since publication. The impact of the ADS on astronomy can be calculated after making some simple assumptions. We find that the ADS increases the efficiency of astronomical research by 333 Full Time Equivalent (2000 hour) research years per year, and that the value of the early development of the ADS for astronomy, compared with waiting for mature technologies to be adopted, is 2332 FTE research years. The ADS is available at http://adswww.harvard.edu/.Comment: 19 pages, 22 figure

    Islets of Langerhans Are Protected from Inflammatory Cell Recruitment during Reperfusion of Rat Pancreas Grafts

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    Background: Ischemia/reperfusion (I/R) injury plays a pivotal role in the development of graft pancreatitis, with ischemia time representing one of its crucial factors. However, it is unclear, whether exocrine and endocrine tissue experience similar inflammatory responses during pancreas transplantation (PTx). This study evaluated inflammatory susceptibilities of islets of Langerhans (ILH) and exocrine tissue after different preservation periods during early reperfusion. Methods: PTx was performed in rats following 2 h (2h-I) or 18 h (18h-I) preservation. Leukocyte-endothelial cell interactions (LEI) were analyzed in venules of acinar tissue and ILH in vivo over 2 h reperfusion. Nontransplanted animals served as controls. Tissue samples were analyzed by histomorphometry. Results: In exocrine venules leukocyte rolling predominated in the 2h-I group. In the 18h-I group, additionally, high numbers of adherent leukocytes were found. Histology revealed significant edema formation and leukocyte extravasation in the 18h-I group. Notably, LEI in postcapillary venules of ILH were significantly lower. Leukocyte rolling was only moderately enhanced and few leukocytes were found adherent. Histology revealed minor leukocyte extravasation. Conclusion: Ischemia time contributes decisively to the extent of the I/R-injury in PTx. However, ILH have a significantly lower susceptibility towards I/R, even when inflammatory reactions in adjacent exocrine tissue are evident. Copyright (C) 2010 S. Karger AG, Base

    Erregungszustände und γ-Hydroxybutyrat

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    Zusammenfassung: Erregungszustände können Ausdruck unterschiedlicher Krankheitsbilder sein. Gamma-Hydroxybutyrat (GHB) wird wegen euphorisierender Effekte missbraucht und kann zu Agitation, Bewusstseinsstörungen und Koma führen. Wir stellen einen 50-jährigen Patienten mit wiederholten GHB-Intoxikationen bei abstinenter Alkoholabhängigkeit und einen videodokumentierten Erregungszustand vor. Die Differenzialdiagnose wird vor dem Hintergrund der aktuellen Literatur diskutiert. GHB-Intoxikation und -Abhängigkeit stellen auch im nervenärztlichen Kontext wichtige Krankheitsbilder da
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