636 research outputs found

    The potential hazard of staphylococci and micrococci to human subjects in a life support systems evaluator and on a diet of precooked freeze dehydrated foods

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    Distribution, and hazards of indigenous microbial populations in humans during prolonged space flight simulatio

    Micro Concentrator Concept for Cost Reduction and Efficiency Enhancement of Thin Film Chalcopyrite Photovoltaics Results from EU Joint Research Program CHEETAH

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    Results for research on chalcopyrite micro concentrator solar cells obtained within the framework of CHEETAH joint program are shown. A top down proof of concept study reveals close to 30 relative efficiency increase under light concentration using inkjet printed CIGSSe. A novel bottom up approach for local chalcopyrite absorbers grown from indium islands demonstrates working CISe micro cells. Millimeter sized lenses are fabricated from PMMA by a casting process to be applied as concentrator optics. For a combined exploitation of direct and diffuse light components an angular splitting concentrator based on chalcopyrite and kesterite absorber material is proposed. The scientific innovation brought will enrich further development of CIGSe solar cells and contribute to their relevance in photovoltaic energy productio

    Towards a normative theological foundation as a Manifesto for sports ministry leaders

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    Op weg na ? normatiewe teologiese fundering tot ? Manifes vir sportbedieningsleiersDie sentrale fokus van hierdie artikel is om aan te toon dat ? normatiewe teologiese fundering vir sportbedieningsleiers as ? Manifes ontwikkel behoort te word. Die vraag na ? normatiewe teologiese fundering vir sportbediening is ? relatiewe nuwe terrein van navorsing. Die oorwig van outeurs oor hierdie onderwerp erken dat die sportbedieningsbeweging ontwikkel het sonder ? duidelike teologie van sport. Die doelwit van hierdie artikel is derhalwe om ? normatiewe teologiese fundering te ontwikkel om dié uitdaging aan te pak. Die metode wat gebruik is, is om kort verklarings te gee van vyf Skrifgedeeltes wat moontlik gebruik kan word as vertrekpunte en om ? bydrae te lewer tot ? Manifes vir sportbedieningsleiers. Vir elkeen van die vyf gedeeltes wat hanteer is, is die fokus telkens op drie hoofsake van die eksegese, naamlik a) hoekom die gedeelte gekies is, b) die relevansie van die gedeelte vir sportbedieningsleiers van vandag en c) basiese teologiese beginsels wat uit elke perikoop afgelei kan word. Ten slotte stel die artikel ? normatiewe teologiese Manifes voor (afgelei uit die verklaring van die vyf gedeeltes) vir sportbedieningsleiers wat hulle kan rig en help toerus vir ? volhoubare sportbediening. The central focus of this article is to show that a normative theological foundation for sports ministry leaders as a Manifesto should be developed. Seeking a normative theological foundation for sports ministry is a relatively new field of research. Most authors on the subject acknowledge that the sports ministry movement has developed without a clearly articulated theology of sport. The aim of this article is, therefore, to develop a normative theological foundation to address this challenge. This is conducted through providing a short exposition of five passages of Scripture that may be used as points of departure and contribute towards a Manifesto for sports ministry leaders. For each of the five passages the focus is on three primary elements of the exegesis, namely, a) why the passage was chosen, b) the relevance of the passage for sports ministry leaders today, and c) basic theological principles that can be derived from each pericope. Finally, the article proposes a normative theological Manifesto (derived from the exposition of the five passages) for sports ministry leaders that will be able to guide and help to equip them for a sustainable sports ministry

    Revised calibration of the mbt-cbt paleotemperature proxy based on branched tetraether membrane lipids in surface soils

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    The MBT-CBT proxy for the reconstruction of paleotemperatures and past soil pH is based on the distribution of branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids. The Methylation of Branched Tetraether (MBT) and the Cyclisation of Branched Tetraether (CBT) indices were developed to quantify these distributions, and significant empirical relations between these indices and annual mean air temperature (MAT) and/or soil pH were found in a large data set of soils. In this study, we extended this soil dataset to 278 globally distributed surface soils. Of these soils, 26% contains all nine brGDGTs, while in 63% of the soils the seven most common brGDGTs were detected, and the latter were selected for calibration purposes. This resulted in new transfer functions for the reconstruction of pH based on the CBT index: pH = 7.90-1.97 x CBT (r(2) = 0.70; RMSE = 0.8; n = 176), as well as for MAT based on the CBT index and methylation index based on the seven most abundant GDGTs (defined as MBT'): MAT = 0.81-5.67 x CBT + 31.0 x MBT' (r(2) = 0.59; RMSE = 5.0 degrees C; n = 176). The new transfer function for MAT has a substantially lower correlation coefficient than the original equation (r(2) = 0.77). To investigate possible improvement of the correlation, we used our extended global surface soil dataset to statistically derive the indices that best describe the relations of brGDGT composition with MAT and soil pH. These new indices, however, resulted in only a relatively minor increase in correlation coefficients, while they cannot be explained straightforwardly by physiological mechanisms. The large scatter in the calibration cannot be fully explained by local factors or by seasonality, but MAT for soils from arid regions are generally substantially (up to 20 degrees C) underestimated, suggesting that absolute brGDGT-based temperature records for these areas should be interpreted with caution.<br>The applicability of the new MBT'-CBT calibration function was tested using previously published MBT-CBT-derived paleotemperature records covering the last deglaciation in Central Africa and East Asia, the Eocene-Oligocene boundary and the Paleocene-Eocene thermal maximum. The results show that trends remain similar in all records, but that absolute temperature estimates and the amplitude of temperature changes are lower for most records, and generally in better agreement with independent proxy data

    Towards a normative theological foundation as a Manifesto for sports ministry leaders

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    The central focus of this article is to show that a normative theological foundation for sports ministry leaders as a Manifesto should be developed. Seeking a normative theological foundation for sports ministry is a relatively new field of research. Most authors on the subject acknowledge that the sports ministry movement has developed without a clearly articulated theology of sport. The aim of this article is, therefore, to develop a normative theological foundation to address this challenge. This is conducted through providing a short exposition of five passages of Scripture that may be used as points of departure and contribute towards a Manifesto for sports ministry leaders. For each of the five passages the focus is on three primary elements of the exegesis, namely, a) why the passage was chosen, b) the relevance of the passage for sports ministry leaders today, and c) basic theological principles that can be derived from each pericope. Finally, the article proposes a normative theological Manifesto (derived from the exposition of the five passages) for sports ministry leaders that will be able to guide and help to equip them for a sustainable sports ministry

    Halococcus salifodinae sp. nov., an Archaeal Isolate from an Austrian Salt Mine

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    A novel extremely halophilic archaeon (archaebacterium) was isolated from rock salt obtained from an Austrian salt mine. The deposition of the salt is thought to have occurred during the Permian period (225 x 106 to 280 x 10(exp 6) years ago). This organism grew over a pH range of 6.8 to 9.5. Electron microscopy revealed cocci in tetrads or larger clusters. The partial 16S rRNA sequences, polar lipid composition, and menaquinone content suggested that this organism was related to members of the genus Halococcus, while the whole-cell protein patterns, the presence of several unknown lipids, and the presence of pink pigmentation indicated that it was different from previously described coccoid halophiles. We propose that this isolate should be recognized as a new species and should be named Halococcus salifodinae. The type strain is Bl(sub p) (= ATCC 51437 = DSM 8989). A chemotaxonomically similar microorganism was isolated from a British salt mine

    Climate change and freshwater zooplankton: what does it boil down to?

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    Recently, major advances in the climate–zooplankton interface have been made some of which appeared to receive much attention in a broader audience of ecologists as well. In contrast to the marine realm, however, we still lack a more holistic summary of recent knowledge in freshwater. We discuss climate change-related variation in physical and biological attributes of lakes and running waters, high-order ecological functions, and subsequent alteration in zooplankton abundance, phenology, distribution, body size, community structure, life history parameters, and behavior by focusing on community level responses. The adequacy of large-scale climatic indices in ecology has received considerable support and provided a framework for the interpretation of community and species level responses in freshwater zooplankton. Modeling perspectives deserve particular consideration, since this promising stream of ecology is of particular applicability in climate change research owing to the inherently predictive nature of this field. In the future, ecologists should expand their research on species beyond daphnids, should address questions as to how different intrinsic and extrinsic drivers interact, should move beyond correlative approaches toward more mechanistic explanations, and last but not least, should facilitate transfer of biological data both across space and time

    The RESET project: constructing a European tephra lattice for refined synchronisation of environmental and archaeological events during the last c. 100 ka

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    This paper introduces the aims and scope of the RESET project (. RESponse of humans to abrupt Environmental Transitions), a programme of research funded by the Natural Environment Research Council (UK) between 2008 and 2013; it also provides the context and rationale for papers included in a special volume of Quaternary Science Reviews that report some of the project's findings. RESET examined the chronological and correlation methods employed to establish causal links between the timing of abrupt environmental transitions (AETs) on the one hand, and of human dispersal and development on the other, with a focus on the Middle and Upper Palaeolithic periods. The period of interest is the Last Glacial cycle and the early Holocene (c. 100-8 ka), during which time a number of pronounced AETs occurred. A long-running topic of debate is the degree to which human history in Europe and the Mediterranean region during the Palaeolithic was shaped by these AETs, but this has proved difficult to assess because of poor dating control. In an attempt to move the science forward, RESET examined the potential that tephra isochrons, and in particular non-visible ash layers (cryptotephras), might offer for synchronising palaeo-records with a greater degree of finesse. New tephrostratigraphical data generated by the project augment previously-established tephra frameworks for the region, and underpin a more evolved tephra 'lattice' that links palaeo-records between Greenland, the European mainland, sub-marine sequences in the Mediterranean and North Africa. The paper also outlines the significance of other contributions to this special volume: collectively, these illustrate how the lattice was constructed, how it links with cognate tephra research in Europe and elsewhere, and how the evidence of tephra isochrons is beginning to challenge long-held views about the impacts of environmental change on humans during the Palaeolithic. © 2015 Elsevier Ltd.RESET was funded through Consortium Grants awarded by the Natural Environment Research Council, UK, to a collaborating team drawn from four institutions: Royal Holloway University of London (grant reference NE/E015905/1), the Natural History Museum, London (NE/E015913/1), Oxford University (NE/E015670/1) and the University of Southampton, including the National Oceanography Centre (NE/01531X/1). The authors also wish to record their deep gratitude to four members of the scientific community who formed a consultative advisory panel during the lifetime of the RESET project: Professor Barbara Wohlfarth (Stockholm University), Professor Jørgen Peder Steffensen (Niels Bohr Institute, Copenhagen), Dr. Martin Street (Romisch-Germanisches Zentralmuseum, Neuwied) and Professor Clive Oppenheimer (Cambridge University). They provided excellent advice at key stages of the work, which we greatly valued. We also thank Jenny Kynaston (Geography Department, Royal Holloway) for construction of several of the figures in this paper, and Debbie Barrett (Elsevier) and Colin Murray Wallace (Editor-in-Chief, QSR) for their considerable assistance in the production of this special volume.Peer Reviewe
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