500 research outputs found

    Elevation gradients of European climate change in the regional climate model COSMO-CLM

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    A transient climate scenario experiment of the regional climate model COSMO-CLM is analyzed to assess the elevation dependency of 21st century European climate change. A focus is put on near-surface conditions. Model evaluation reveals that COSMO-CLM is able to approximately reproduce the observed altitudinal variation of 2m temperature and precipitation in most regions and most seasons. The analysis of climate change signals suggests that 21st century climate change might considerably depend on elevation. Over most parts of Europe and in most seasons, near-surface warming significantly increases with elevation. This is consistent with the simulated changes of the free-tropospheric air temperature, but can only be fully explained by taking into account regional-scale processes involving the land surface. In winter and spring, the anomalous high-elevation warming is typically connected to a decrease in the number of snow days and the snow-albedo feedback. Further factors are changes in cloud cover and soil moisture and the proximity of low-elevation regions to the sea. The amplified warming at high elevations becomes apparent during the first half of the 21st century and results in a general decrease of near-surface lapse rates. It does not imply an early detection potential of large-scale temperature changes. For precipitation, only few consistent signals arise. In many regions precipitation changes show a pronounced elevation dependency but the details strongly depend on the season and the region under consideration. There is a tendency towards a larger relative decrease of summer precipitation at low elevations, but there are exceptions to this as wel

    Hepatitis-B- und -C-assoziierte Glomerulonephritiden

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    Zusammenfassung: Virale Hepatitiden sind häufig mit extrahepatischen Manifestationen assoziiert. Bei der HepatitisB ist die membranöse Glomerulonephritis (GN) die häufigste histologische Diagnose. Im Rahmen der HepatitisC wird vorwiegend eine membranoproliferative GN mit oder ohne gemischte Kryoglobulinämie beobachtet. Eine zentrale pathogenetische Rolle spielen Immunkomplexe (virale Antigene, antivirale Antikörper, bei Kryoglobulinämie auch Rheumafaktoren). Diese Komplexe werden in der Niere abgelagert und aktivieren Komplement, was schließlich zum Nierenschaden führt. Therapeutisch zentral ist die antivirale Therapie mit dem Ziel der Antigenelimination. Im Falle der HepatitisB kann eine Therapie mit IFNα durchgeführt werden, alternativ mit Lamivudin. Eine immunsuppressive Therapie steht eher im Hintergrund. Bei der HepatitisC ist die Standardtherapie IFNα in Kombination mit Ribavirin. Bei einer zusätzlichen Kryoglobulinämie besteht die Alternative einer Therapie mit Rituximab, bei schwerem Verlauf mit Plasmapherese, Steroiden und Cyclophosphamid. Bei vollständiger Elimination der Virusreplikation ist die Prognose dieser sekundären GN günsti

    Magnetic moments of the 3/2 resonances and their quark spin structure

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    We discuss magnetic moments of the J=3/2J=3/2 baryons based on an earlier model for the baryon magnetic moments, allowing for flavor symmetry breaking in the quark magnetic moments as well as a general quark spin structure. From our earlier analysis of the nucleon-hyperon magnetic moments and the measured values of the magnetic moments of Δ++\Delta^{++} and Ω\Omega^{-} we predict the other magnetic moments and deduce the spin structure of the resonance particles. We find from experiment that the total spin polarization of the decuplet baryons, ΔΣ(3/2)\Delta\Sigma(3/2), is considerably smaller than the non-relativistic quark model value of 3, although the data is still not good enough to give a precise determination.Comment: 13 pages, REVTeX, 2 figures, minor clarifying change

    Magnetic Moments of the Baryon Decuplet in a Relativistic Quark Model

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    The magnetic moments of the baryon decuplet are calculated in a relativistic constituent quark model using the light-front formalism. Of particular interest are the magnetic moments of the Ω\Omega^- and Δ++\Delta^{++} for which new recent experimental measurements are available. Our calculation for the magnetic moment ratio μ(Δ++)/μ(p)\mu(\Delta^{++})/\mu(p) is in excellent agreement with the experimental ratio, while our ratio μ(Ω)/μ(Λ0)\mu(\Omega^-)/\mu(\Lambda^0) is slightly higher than the experimental ratio.Comment: 10 pages ReVTeX, SLAC-PUB-621

    Quark Orbital Angular Momentum in the Baryon

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    Analytical and numerical results, for the orbital and spin content carried by different quark flavors in the baryons, are given in the chiral quark model with symmetry breaking. The reduction of the quark spin, due to the spin dilution in the chiral splitting processes, is transferred into the orbital motion of quarks and antiquarks. The orbital angular momentum for each quark flavor in the proton as a function of the partition factor κ\kappa and the chiral splitting probability aa is shown. The cancellation between the spin and orbital contributions in the spin sum rule and in the baryon magnetic moments is discussed.Comment: 26 pages, 3 figures, revised version with minor eq. no and ref. no. corrections. Discussion on the Λ\Lambda spin and a new ref. are adde

    Cascaded two-photon nonlinearity in a one-dimensional waveguide with multiple two-level emitters

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    We propose and theoretically investigate a model to realize cascaded optical nonlinearity with few atoms and photons in one-dimension (1D). The optical nonlinearity in our system is mediated by resonant interactions of photons with two-level emitters, such as atoms or quantum dots in a 1D photonic waveguide. Multi-photon transmission in the waveguide is nonreciprocal when the emitters have different transition energies. Our theory provides a clear physical understanding of the origin of nonreciprocity in the presence of cascaded nonlinearity. We show how various two-photon nonlinear effects including spatial attraction and repulsion between photons, background fluorescence can be tuned by changing the number of emitters and the coupling between emitters (controlled by the separation).Comment: 6 pages, 4 figure

    A new diagnostic algorithm for Burkitt and diffuse large B-cell lymphomas based on the expression of CSE1L and STAT3 and on MYC rearrangement predicts outcome

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    Background Aggressive mature B-cell non-Hodgkin's lymphomas (BCL) sharing features of Burkitt's lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) (intermediate BL/DLBCL) but deviating with respect to one or more characteristics are increasingly recognized. The limited knowledge about these biologically heterogeneous lymphomas hampers their assignment to a known entity, raising incertitude about optimal treatment approaches. We therefore searched for discriminative, prognostic, and predictive factors for their better characterization. Patients and methods We analyzed 242 cytogenetically defined aggressive mature BCL for differential protein expression. Marker selection was based on recent gene-expression profile studies. Predictive models for diagnosis were established and validated by a different set of lymphomas. Results CSE1L- and inhibitor of DNA binding-3 (ID3)-overexpression was associated with the diagnosis of BL and signal transduction and transcription-3 (STAT3) with DLBCL (P<0.001 for all markers). All three markers were associated with patient outcome in DLBCL. A new algorithm discriminating BL from DLBCL emerged, including the expression of CSE1L, STAT3, and MYC translocation. This ‘new classifier' enabled the identification of patients with intermediate BL/DLBCL who benefited from intensive chemotherapy regimens. Conclusion The proposed algorithm, which is based on markers with reliable staining properties for routine diagnostics, represents a novel valid tool in separating BL from DLBCL. Most interestingly, it allows segregating intermediate BL/DLBCL into groups with different treatment requirement

    MAR-Mediated transgene integration into permissive chromatin and increased expression by recombination pathway engineering.

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    Untargeted plasmid integration into mammalian cell genomes remains a poorly understood and inefficient process. The formation of plasmid concatemers and their genomic integration has been ascribed either to non-homologous end-joining (NHEJ) or homologous recombination (HR) DNA repair pathways. However, a direct involvement of these pathways has remained unclear. Here, we show that the silencing of many HR factors enhanced plasmid concatemer formation and stable expression of the gene of interest in Chinese hamster ovary (CHO) cells, while the inhibition of NHEJ had no effect. However, genomic integration was decreased by the silencing of specific HR components, such as Rad51, and DNA synthesis-dependent microhomology-mediated end-joining (SD-MMEJ) activities. Genome-wide analysis of the integration loci and junction sequences validated the prevalent use of the SD-MMEJ pathway for transgene integration close to cellular genes, an effect shared with matrix attachment region (MAR) DNA elements that stimulate plasmid integration and expression. Overall, we conclude that SD-MMEJ is the main mechanism driving the illegitimate genomic integration of foreign DNA in CHO cells, and we provide a recombination engineering approach that increases transgene integration and recombinant protein expression in these cells. Biotechnol. Bioeng. 2017;114: 384-396. © 2016 The Authors. Biotechnology and Bioengineering published by Wiley Periodicals, Inc

    Magnetic moments of the SU(3) decuplet baryons in the chiral quark-soliton model

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    Magnetic moments of baryons are studied within the chiral quark soliton model with special emphasis on the decuplet of baryons. The model is used to identify all symmetry breaking terms proportional to msm_{\rm s}. Sum rules for the magnetic moments are derived. A ``model-independent'' analysis of the symmetry breaking terms is performed and finally model calculations are presented, which show the importance of the rotational 1/Nc1/N_{\rm c} corrections for cranking of the soliton.Comment: 22 pages, RevTex. The final version accepted for publication in Phys. Rev.

    Electromagnetic Moments of the Baryon Decuplet

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    We compute the leading contributions to the magnetic dipole and electric quadrupole moments of the baryon decuplet in chiral perturbation theory. The measured value for the magnetic moment of the Ω\Omega^- is used to determine the local counterterm for the magnetic moments. We compare the chiral perturbation theory predictions for the magnetic moments of the decuplet with those of the baryon octet and find reasonable agreement with the predictions of the large--NcN_c limit of QCD. The leading contribution to the quadrupole moment of the Δ\Delta and other members of the decuplet comes from one--loop graphs. The pionic contribution is shown to be proportional to IzI_z (and so will not contribute to the quadrupole moment of I=0I=0 nuclei), while the contribution from kaons has both isovector and isoscalar components. The chiral logarithmic enhancement of both pion and kaon loops has a coefficient that vanishes in the SU(6)SU(6) limit. The third allowed moment, the magnetic octupole, is shown to be dominated by a local counterterm with corrections arising at two loops. We briefly mention the strange counterparts of these moments.Comment: Uses harvmac.tex, 15 pages with 3 PostScript figures packed using uufiles. UCSD/PTH 93-22, QUSTH-93-05, Duke-TH-93-5
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