306 research outputs found

    ARAC modeling of SARMAP tracer releases

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    Keck telescope constraint on cosmological variation of the proton-to-electron mass ratio

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    Molecular transitions recently discovered at redshift z_abs=2.059 toward the bright background quasar J2123-0050 are analysed to limit cosmological variation in the proton-to-electron mass ratio, mu=m_p/m_e. Observed with the Keck telescope, the optical echelle spectrum has the highest resolving power and largest number (86) of H_2 transitions in such analyses so far. Also, (seven) HD transitions are used for the first time to constrain mu-variation. These factors, and an analysis employing the fewest possible free parameters, strongly constrain mu's relative deviation from the current laboratory value: dmu/mu =(+5.6+/-5.5_stat+/-2.9_sys)x10^{-6}, indicating an insignificantly larger mu in the absorber. This is the first Keck result to complement recent null constraints from three systems at z_abs>2.5 observed with the Very Large Telescope. The main possible systematic errors stem from wavelength calibration uncertainties. In particular, distortions in the wavelength solution on echelle order scales are estimated to contribute approximately half the total systematic error component, but our estimate is model dependent and may therefore under or overestimate the real effect, if present. To assist future mu-variation analyses of this kind, and other astrophysical studies of H_2 in general, we provide a compilation of the most precise laboratory wavelengths and calculated parameters important for absorption-line work with H_2 transitions redwards of the hydrogen Lyman limit.Comment: 15 pages, 8 figures (8 EPS files), 3 tables. Accepted by MNRAS. ArXiv copy includes full version of Fig. 1 (additional 8 pages, 7 EPS files). Complete version of Table 1 available at http://astronomy.swin.edu.au/~mmurphy/pub.htm

    Structure of the mature Rous sarcoma virus lattice reveals a role for IP6 in the formation of the capsid hexamer

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    Inositol hexakisphosphate (IP6) is an assembly cofactor for HIV-1. We report here that IP6 is also used for assembly of Rous sarcoma virus (RSV), a retrovirus from a different genus. IP6 is ~100-fold more potent at promoting RSV mature capsid protein (CA) assembly than observed for HIV-1 and removal of IP6 in cells reduces infectivity by 100-fold. Here, visualized by cryo-electron tomography and subtomogram averaging, mature capsid-like particles show an IP6-like density in the CA hexamer, coordinated by rings of six lysines and six arginines. Phosphate and IP6 have opposing effects on CA in vitro assembly, inducing formation of T = 1 icosahedrons and tubes, respectively, implying that phosphate promotes pentamer and IP6 hexamer formation. Subtomogram averaging and classification optimized for analysis of pleomorphic retrovirus particles reveal that the heterogeneity of mature RSV CA polyhedrons results from an unexpected, intrinsic CA hexamer flexibility. In contrast, the CA pentamer forms rigid units organizing the local architecture. These different features of hexamers and pentamers determine the structural mechanism to form CA polyhedrons of variable shape in mature RSV particles

    Metabotropic glutamate receptor 5 (mGluR5) regulates bladder nociception

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    <p>Abstract</p> <p>Background</p> <p>Interstitial cystitis/painful bladder syndrome (IC/PBS), is a severely debilitating chronic condition that is frequently unresponsive to conventional pain medications. The etiology is unknown, however evidence suggests that nervous system sensitization contributes to enhanced pain in IC/PBS. In particular, central nervous system plasticity of glutamatergic signaling involving NMDA and metabotropic glutamate receptors (mGluRs) has been implicated in a variety of chronic pain conditions. Here, we test the hypothesis that mGluR5 mediates both non-inflammatory and inflammatory bladder pain or nociception in a mouse model by monitoring the visceromotor response (VMR) during graded bladder distention.</p> <p>Results</p> <p>Using a combination of genetic and pharmacologic approaches, we provide evidence indicating that mGluR5 is necessary for the full expression of VMR in response to bladder distention in the absence of inflammation. Furthermore, we observed that mice infected with a uropathogenic strain of <it>Escherichia coli </it>(UPEC) develop inflammatory hyperalgesia to bladder distention, and that the selective mGluR5 antagonist fenobam [N-(3-chlorophenyl)-N'-(4,5-dihydro-1-methyl-4-oxo-1H-imidazole-2-yl) urea], reduces the VMR to bladder distention in UPEC-infected mice.</p> <p>Conclusions</p> <p>Taken together, these data suggest that mGluR5 modulates both inflammatory and non-inflammatory bladder nociception, and highlight the therapeutic potential for mGluR5 antagonists in the alleviation of bladder pain.</p

    Wirtschaftlichkeit der Aufzucht von Altsteirer-Gebrauchskreuzungen unter Praxisbedingungen

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    Es wurden Kreuzungen mit Altsteirer Hähnen und legebetonten oder mastbetonten Hennen erstellt. Die größte Herausforderung ist die Vermarktung der männlichen Nachkommen bei hohen Kosten für Futter und Arbeitszeit. Eine wirtschaftliche Aufzucht der Hähne ist unter praktischen Bedingungen möglich

    Kooperationsstudiengänge

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    Der Think-Tank befasste sich mit den Herausforderungen für Organisation, Technik und Recht rund um Kooperationen im Bereich von Studium und Lehre der baden-württembergischen Hochschulen. Zwischen den Hochschulen existieren Kooperationen, die sich durch unterschiedliche Formen und Grade der Zusammenarbeit, aber auch teilweise durch unterschiedliche rechtliche Rahmenbedingungen ausweisen. In diesem Whitepaper wird das Gesamtthema Kooperationsstudiengänge beleuchtet. Die Betrachtung geht über die Studiengänge im engeren Sinn hinaus und schließt Kooperationsformen, die auf dem Austausch einzelner Module basieren, mit ein. Zur weiteren Erschließung der Thematik erfolgt eine Strukturierung des Themas und daraus abgeleitete Vorschläge für erste konkrete Handlungsfelder. Es werden Querbezüge zur Initiative „Europäische Universitäten“ hergestellt sowie eine Übersicht der verschiedenen Aktivitäten präsentiert. Außerdem werden Querbezüge zu Projekten, die Themen im Zusammenhang mit Kooperationen erschließen oder bereits erschlossen haben, geschaffen. Neben konkreten Handlungsempfehlungen werden Themenfelder, die über diesen Think-Tank hinausgehen und eine intensivere Betrachtung benötigen, identifiziert

    Outcomes of parathyroidectomy versus calcimimetics for secondary hyperparathyroidism and kidney transplantation:a propensity-matched analysis

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    Purpose: Calcimimetics are currently indicated for severe secondary hyperparathyroidism (SHPT). However, the role of parathyroidectomy (PTX) for these patients is still under debate, and its impact on subsequent kidney transplantation (KTX) is unclear. In this study, we compare the outcomes of kidney transplantation after PTX or medical treatment. Methods: Patients who underwent KTX and had SHPT were analyzed retrospectively. Two groups were selected (patients who had either PTX or calcimimetics prior to KTX) using a propensity score for sex, age, donor type, and parathyroid hormone levels (PTH) during dialysis. The primary outcome was graft failure, and secondary outcomes were surgical KTX complications, survival, serum PTH, serum calcium, and serum phosphate levels post-KTX. Results: Matching succeeded for 92 patients. After PTX, PTH was significantly lower on the day of KTX as well as at 1 and 3 years post-KTX (14.00 pmol/L (3.80–34.00) vs. 71.30 pmol/L (30.70–108.30), p < 0.01, 10.10 pmol/L (2.00–21.00) vs. 32.35 pmol/L (21.58–51.76), p < 0.01 and 13.00 pmol/L (6.00–16.60) vs. 19.25 pmol/L (13.03–31.88), p = 0.027, respectively). No significant differences in post-KTX calcium and phosphate levels were noted between groups. Severe KTX complications were more common in the calcimimetics group (56.5% vs. 30.4%, p = 0.047). There were no differences in 10-year graft failure and overall survival. Conclusion: PTX resulted in lower PTH after KTX in comparison to patients who received calcimimetics. Severe complications were more common after calcimimetics, but graft failure and overall survival were similar

    3R Blackboard: A platform for animal and organ sharing

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    Since the embedding of the principles of the 3Rs (Replacement, Reduction and Refinement) in national and international regulations on the use of animals, scientists have been challenged to find ways to reduce the number of animals in their research. Here, we present a digital platform, called ‘3R Backboard’, linked to a laboratory animal management system, which facilitates sharing of surplus biological materials from animals (e.g. tissues, organs and cells) to other research teams. Based on information provided, such as genotype, age and sex, other animal workers were able to indicate their interest in collecting specific tissues and to communicate with the person providing the animals. A short pilot study of this approach conducted in a limited academic environment presented strong evidence of its effectiveness and resulted in a notable reduction of the number of mice used. In addition, the use of 3R Blackboard led to resource saving, knowledge exchange and even establishment of new collaboration

    Influence of Polymorphism on the Electronic Structure of Ga2O3

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    The search for new wide band gap materials is intensifying to satisfy the need for more advanced and energy efficient power electronic devices. Ga2_2O3_3 has emerged as an alternative to SiC and GaN, sparking a renewed interest in its fundamental properties beyond the main β\beta-phase. Here, three polymorphs of Ga2_2O3_3, α\alpha, β\beta and ε\varepsilon, are investigated using X-ray diffraction, X-ray photoelectron and absorption spectroscopy, and ab initio theoretical approaches to gain insights into their structure - electronic structure relationships. Valence and conduction electronic structure as well as semi-core and core states are probed, providing a complete picture of the influence of local coordination environments on the electronic structure. State-of-the-art electronic structure theory, including all-electron density functional theory and many-body perturbation theory, provide detailed understanding of the spectroscopic results. The calculated spectra provide very accurate descriptions of all experimental spectra and additionally illuminate the origin of observed spectral features. This work provides a strong basis for the exploration of the Ga2_2O3_3 polymorphs as materials at the heart of future electronic device generations.Comment: Updated manuscript version after peer revie
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