140 research outputs found

    Dissection of the Barley 2L1.0 region carrying the ‘Laevigatum’ quantitative resistance gene to leaf rust using Near-Isogenic lines (NIL) and subNIL

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    Partial resistance to leaf rust (Puccinia hordei G. H. Otth) in barley is a quantitative resistance that is not based on hypersensitivity. This resistance hampers haustorium formation, resulting in a long latency period in greenhouse tests. The three most consistent quantitative trait loci (QTL) uncovered in the L94 × ‘Vada’ mapping population were introgressed by marker-assisted backcrossing into the susceptible L94 background to obtain near-isogenic lines (NIL). We also developed the reciprocal Vada-NIL for the susceptibility alleles of those QTL. The QTL Rphq2 affected latency period of P. hordei more than the QTL Rphq3 and Rphq4. The NIL confirmed the contribution of Rphq2 to partial resistance by prolonging the latency period by 28 h on L94-Rphq2 and shortening the latency period by 23 h on Vada-rphq2. On the basis of flanking restriction fragment length polymorphism-based markers, Rphq2 appeared to be located near the telomeric end of the long arm of chromosome 2H, in a physical region of high recombination, making it the target QTL for map-based cloning. Microscopic observations on the NIL confirmed the nonhypersensitive nature of the resistance conferred by Rphq2. A high-resolution genetic map of the Rphq2 region was constructed using a population of 38 subNIL with overlapping L94 introgressions in Vada background across the region. Rphq2 mapped approximately 2 centimorgans (cM) proximal from the MlLa locus. By bulked segregant analysis and use of synteny with rice, we developed additional markers and fine-mapped Rphq2 to a genetic interval of 0.11 cM that corresponds to a stretch of sequence of, at most, 70 kb in rice. Analysis of this rice sequence revealed predicted genes encoding two proteins with unknown function, retrotransposon proteins, peroxidase proteins, and a protein similar to a mitogen-activated protein kinase kinase kinase (MAP3K). Possible homologs of those peroxidases and MAP3K in barley are candidates for the gene that contributes to partial resistance to P. hordei

    Modelling of Tirapazamine effects on solid tumour morphology

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    Bioreductive drugs are in clinical practice to exploit the resistance from tumour microenvironments especially in the hypoxic region of tumour. We pre-sented a tumour treatment model to capture the pharmacology of one of the most prominent bioreductive drugs, Tirapazamine (TPZ) which is in clinical trials I and II. We calculated solid tumour mass in our previous work and then integrated that model with TPZ infusion. We calculated TPZ cytotoxicity, concentration, penetra-tion with increasing distance from blood vessel and offered resistance from micro-environments for drug penetration inside the tumour while considering each cell as an individual entity. The impact of these factors on tumour morphology is also showed to see the drug behaviour inside animals/humans tumours. We maintained the heterogeneity factors in presented model as observed in real tumour mass es-pecially in terms of cells proliferation, cell movement, extracellular matrix (ECM) interaction, and the gradients of partial oxygen pressure (pO2) inside tumour cells during the whole growth and treatment activity. The results suggest that TPZ high concentration in combination with chemotherapy should be given to get maximum abnormal cell killing. This model can be a good choice for oncologists and re-searchers to explore more about TPZ action inside solid tumour

    Global Relationships Between River Width, Slope, Catchment Area, Meander Wavelength, Sinuosity, and Discharge

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    Using river centerlines created with Landsat images and the Shuttle Radar Topography Mission digital elevation model, we created spatially continuous maps of mean annual flow river width, slope, meander wavelength, sinuosity, and catchment area for all rivers wider than 90 m located between 60°N and 56°S. We analyzed the distributions of these properties, identified their typical ranges, and explored relationships between river planform and slope. We found width to be directly associated with the magnitude of meander wavelength and catchment area. Moreover, we found that narrower rivers show a larger range of slope and sinuosity values than wider rivers. Finally, by comparing simulated discharge from a water balance model with measured widths, we show that power laws between mean annual discharge and width can predict width typically to −35% to +81%, even when a single relationship is applied across all rivers with discharge ranging from 100 to 50,000 m3/s

    Two-Loop O(αsGFmt2){\cal O}(\alpha_sG_Fm_t^2) Corrections to the Fermionic Decay Rates of the Standard-Model Higgs Boson

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    Low- and intermediate mass Higgs bosons decay preferably into fermion pairs. The one-loop electroweak corrections to the respective decay rates are dominated by a flavour-independent term of O(GFmt2){\cal O}(G_Fm_t^2). We calculate the two-loop gluon correction to this term. It turns out that this correction screens the leading high-mtm_t behaviour of the one-loop result by roughly 10\%. We also present the two-loop QCD correction to the contribution induced by a pair of fourth-generation quarks with arbitrary masses. As expected, the inclusion of the QCD correction considerably reduces the renormalization-scheme dependence of the prediction.Comment: 14 pages, latex, figures 2-5 appended, DESY 94-08

    Proceedings from the 2nd European Clinical Consensus Conference for device-based therapies for hypertension: state of the art and considerations for the future.

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    The interest in RDN for hypertension has fluctuated recently, with a flurry of initial enthusiasm followed by sudden loss of interest by researchers and device manufacturers, with an almost as sudden resurgence in clinical trials activity and device innovation more recently. There is widespread consensus that this therapeutic strategy can be effective, at least for some of the technologies available. Major uncertainties remain as to the clinical role of RDN, and whether any of the emerging technologies such as AV-anastomosis formation, carotid body ablation, carotid bulb expansion, or baroreflex stimulation will have a future as effective treatment options in patients with hypertension. In our first consensus report in 2015, the European Expert Group pointed to the major unmet need of standardization of measurements, trial design and procedural performance.6 With the large number of different technologies currently in the pipeline, this need has even increased. Only through high-quality, collaborative research and openness to new methods for recruitment, patient selection, and assessment of outcomes will it be possible to establish incontrovertibly whether device therapies for hypertension are effective and what are preferred patient populations. Once the proof of concept is established, further studies with a design relevant to clinical reality will be needed to establish the place of new devices in the treatment armoury. The clinical and research community has a large responsibility to prove or disprove the value of new therapies, in order to ensure that antihypertensive devices provide future patients with the greatest benefit and the smallest risk. copy; The Author 2017

    Photoproduction of pions and properties of baryon resonances from a Bonn-Gatchina partial wave analysis

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    Masses, widths and photocouplings of baryon resonances are determined in a coupled-channel partial wave analysis of a large variety of data. The Bonn-Gatchina partial wave formalism is extended to include a decomposition of t- and u-exchange amplitudes into individual partial waves. The multipole transition amplitudes for γppπ0\gamma p\to p\pi^0 and γpnπ+\gamma p\to n\pi^+ are given and compared to results from other analyses.Comment: 18 pages, 14 figure

    P-wave excited baryons from pion- and photo-induced hyperon production

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    We report evidence for N(1710)P11N(1710)P_{11}, N(1875)P11N(1875)P_{11}, N(1900)P13N(1900)P_{13}, Δ(1600)P33\Delta(1600)P_{33}, Δ(1910)P31\Delta(1910)P_{31}, and Δ(1920)P33\Delta(1920)P_{33}, and find indications that N(1900)P13N(1900)P_{13} might have a companion state at 1970\,MeV. The controversial Δ(1750)P31\Delta(1750)P_{31} is not seen. The evidence is derived from a study of data on pion- and photo-induced hyperon production, but other data are included as well. Most of the resonances reported here were found in the Karlsruhe-Helsinki (KH84) and the Carnegie-Mellon (CM) analyses but were challenged recently by the Data Analysis Center at GWU. Our analysis is constrained by the energy independent πN\pi N scattering amplitudes from either KH84 or GWU. The two πN\pi N amplitudes from KH84 or GWU, respectively, lead to slightly different πN\pi N branching ratios of contributing resonances but the debated resonances are required in both series of fits.Comment: 22 pages, 28 figures. Some additional sets of data are adde
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