1,011 research outputs found

    Meta-Analysis of Mitochondrial DNA Reveals Several Population Bottlenecks during Worldwide Migrations of Cattle

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    Several studies have investigated the differentiation of mitochondrial DNA in Eurasian, African and American cattle as well as archaeological bovine material. A global survey of these studies shows that haplogroup distributions are more stable in time than in space. All major migrations of cattle have shifted the haplogroup distributions considerably with a reduction of the number of haplogroups and/or an expansion of haplotypes that are rare or absent in the ancestral populations. The most extreme case is the almost exclusive colonization of Africa by the T1 haplogroup, which is rare in Southwest Asian cattle. In contrast, ancient samples invariably show continuity with present-day cattle from the same location. These findings indicate strong maternal founder effects followed by limited maternal gene flow when new territories are colonized. However, effects of adaptation to new environments may also play a rol

    Simultaneous data collection of small maritime targets using multistatic radar and forward scatter radar

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    Radar detection of small maritime targets is of great interest in the context of coastal and port security for prevention of activities such as smuggling and piracy. Multistatic radar and forward scatter radar offer detection advantages compared with conventional monostatic systems, such as advantageous multi-perspective target view for the former and target radar cross-section enhancement for the latter. In this study, experimental results are presented to characterise simultaneous measurements investigating the detection of a small inflatable boat by a multistatic radar and a forward scatter radar. These results are believed to be the first example of simultaneous experimental comparison of such systems

    Meta-Analysis of mitochondrial DNA reveals several population bottlenecks during worldwide migrations of cattle

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    Several studies have investigated the differentiation of mitochondrial DNA in Eurasian, African and American cattle as well as archaeological bovine material. A global survey of these studies shows that haplogroup distributions are more stable in time than in space. All major migrations of cattle have shifted the haplogroup distributions considerably with a reduction of the number of haplogroups and/or an expansion of haplotypes that are rare or absent in the ancestral populations. The most extreme case is the almost exclusive colonization of Africa by the T1 haplogroup, which is rare in Southwest Asian cattle. In contrast, ancient samples invariably show continuity with present-day cattle from the same location. These findings indicate strong maternal founder effects followed by limited maternal gene flow when new territories are colonized. However, effects of adaptation to new environments may also play a role.Facultad de Ciencias VeterinariasInstituto de Genética Veterinari

    Passive multifrequency forward-scatter radar measurements of airborne targets using broadcasting signals

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    This paper demonstrates the feasibility and effectiveness of forward-scatter radar (FSR) target detection based on the signals of opportunity made available by standard radio and TV broadcast transmission stations. This passive FSR (P-FSR) operation is obtained by means of a simple and robust correlation process based on self-mixing. This is shown to be very effective in extracting the characteristic FSR modulation produced by airborne targets, from the signals received from frequency modulated, digital audio broadcasting, and digital video broadcasting transmitters of opportunity. Target detectability is discussed as a function of the carrier frequency, the target size, and its height at the baseline crossing. Experimental results are shown using a wide variety of sources of opportunity, target types, baselines, and receiver configurations. The target signatures obtained from the different illuminators are compared and ways of extracting the kinematic parameters of the aircraft are discussed. This validates the claimed effectiveness and robustness of the P-FSR with the presented processing scheme

    Richard Löwenherz im Museum : Menschen und Objekte in Bewegung

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    Irgendwo in unserem sogenannten Allgemeinwissen über das Mittelalter ist auch die Vorstellung verankert, dass das Leben früher ruhiger, gemütlicher und nicht so hektisch war wie heute. Früher, als die Welt noch ‚normal’ war, hatten die meisten Menschen einen festen Lebensmittelpunkt, waren fest verwurzelt in einer Gemeinschaft und verließen ihre Heimat nur dann, wenn es sich gar nicht vermeiden lies. Nur wenige – nämlich die besonders Überprivilegierten und die besonders Unterprivilegierten -, also die, die es sich leisten konnten oder die, die dazu gezwungen wurden, waren unterwegs. Alle anderen blieben ein Leben lang zuhause, an dem Ort, an dem sie ihren festen Lebensmittelpunkt hatten. Soweit unser intuitives Vorwissen darüber, wie es früher, also auch schon im Mittelalter, gewesen sein muss. Dieses mehr ‚gefühlte’ als wissenschaftlich erwiesene Vorwissen haben wir im Rahmen eines Hauptseminars zur Geschichte des Mittelalters im Herbst 2017 gründlich hinterfragt. Ausgangspunkt war die Ausstellung „Richard Löwenherz“, die im September am Historischen Museum der Pfalz in Speyer eröffnet wurde. Ein Seminar zum Thema führte uns auf die Spuren der im Museum gezeigten Objekte, von dort auf die Spuren der Menschen im Umfeld des berühmten Königs von England

    Meta-Analysis of mitochondrial DNA reveals several population bottlenecks during worldwide migrations of cattle

    Get PDF
    Several studies have investigated the differentiation of mitochondrial DNA in Eurasian, African and American cattle as well as archaeological bovine material. A global survey of these studies shows that haplogroup distributions are more stable in time than in space. All major migrations of cattle have shifted the haplogroup distributions considerably with a reduction of the number of haplogroups and/or an expansion of haplotypes that are rare or absent in the ancestral populations. The most extreme case is the almost exclusive colonization of Africa by the T1 haplogroup, which is rare in Southwest Asian cattle. In contrast, ancient samples invariably show continuity with present-day cattle from the same location. These findings indicate strong maternal founder effects followed by limited maternal gene flow when new territories are colonized. However, effects of adaptation to new environments may also play a role.Facultad de Ciencias VeterinariasInstituto de Genética Veterinari

    A Roadmap for HEP Software and Computing R&D for the 2020s

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    Particle physics has an ambitious and broad experimental programme for the coming decades. This programme requires large investments in detector hardware, either to build new facilities and experiments, or to upgrade existing ones. Similarly, it requires commensurate investment in the R&D of software to acquire, manage, process, and analyse the shear amounts of data to be recorded. In planning for the HL-LHC in particular, it is critical that all of the collaborating stakeholders agree on the software goals and priorities, and that the efforts complement each other. In this spirit, this white paper describes the R&D activities required to prepare for this software upgrade.Peer reviewe

    Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

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    Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

    Long-range angular correlations on the near and away side in p&#8211;Pb collisions at

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    Measurement of the B0s→μ+μ− Branching Fraction and Effective Lifetime and Search for B0→μ+μ− Decays

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    A search for the rare decays Bs0→μ+μ- and B0→μ+μ- is performed at the LHCb experiment using data collected in pp collisions corresponding to a total integrated luminosity of 4.4  fb-1. An excess of Bs0→μ+μ- decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(Bs0→μ+μ-)=(3.0±0.6-0.2+0.3)×10-9, where the first uncertainty is statistical and the second systematic. The first measurement of the Bs0→μ+μ- effective lifetime, τ(Bs0→μ+μ-)=2.04±0.44±0.05  ps, is reported. No significant excess of B0→μ+μ- decays is found, and a 95% confidence level upper limit, B(B0→μ+μ-)<3.4×10-10, is determined. All results are in agreement with the standard model expectations.A search for the rare decays Bs0μ+μB^0_s\to\mu^+\mu^- and B0μ+μB^0\to\mu^+\mu^- is performed at the LHCb experiment using data collected in pppp collisions corresponding to a total integrated luminosity of 4.4 fb1^{-1}. An excess of Bs0μ+μB^0_s\to\mu^+\mu^- decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(Bs0μ+μ)=(3.0±0.60.2+0.3)×109{\cal B}(B^0_s\to\mu^+\mu^-)=\left(3.0\pm 0.6^{+0.3}_{-0.2}\right)\times 10^{-9}, where the first uncertainty is statistical and the second systematic. The first measurement of the Bs0μ+μB^0_s\to\mu^+\mu^- effective lifetime, τ(Bs0μ+μ)=2.04±0.44±0.05\tau(B^0_s\to\mu^+\mu^-)=2.04\pm 0.44\pm 0.05 ps, is reported. No significant excess of B0μ+μB^0\to\mu^+\mu^- decays is found and a 95 % confidence level upper limit, B(B0μ+μ)<3.4×1010{\cal B}(B^0\to\mu^+\mu^-)<3.4\times 10^{-10}, is determined. All results are in agreement with the Standard Model expectations
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