67 research outputs found

    Evaluation of radiative transfer schemes for mesoscale model data assimilation: a case study

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    International audienceThe assimilation of Special Sensor Microwave Imager (SSM/I) data into the Mesoscale Model 5 (MM5) allows for improving the weather forecast. However the results suggested an update the Radiative Transfer Equation (RTE) within the three-dimensional variational (3DVAR) algorithm which is tailored for non rainy conditions only. To this purpose, a new RTE algorithm is tested, in order to account for radiometric response in rainy regions. The new brightness temperatures (TB) are estimated by using hydrometeor profiles from the MM5 mesoscale model, running with two different microphysical parameterizations. The goodness of the results is assessed by comparing the new TB with those of the original RTE algorithm in the 3DVAR code and the SSM/I observed data. The results confirm a better reliability of the new RTE compared to the old one

    growth performance meat quality traits and genetic mapping of quantitative trait loci in 3 generations of japanese quail populations coturnix japonica

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    Abstract The current research was conducted to compare growth, carcass traits, pH, intramuscular collagen (IMC) properties, and genetic bases of IMC and carcasses (breast-muscle weight) of different lines and generations of adult males and females of Japanese quail (Coturnix japonica). Forty-four quails (generation F0), 22 Pharaoh (F-33) meat-type males and 22 Standard (S-22) laying-type females, were crossed to produce the F1 hybrids generation. The F2 generation was created by mating one F1 male with one F1 female, full siblings. The birds, randomly chosen from F0 (22 males and 22 females), F1 (22 males and 22 females), and F2 (84 males and 152 females) were raised to 20 wk of age in collective cages. Quails were fed ad libitum commercial diets. At slaughter, all birds were individually weighed (after a fasting period of 12 h) and dressing yield (without giblets) was calculated. The carcasses were then dissected. Genomic DNA was extracted from all of the blood, and 30 microsatellite markers located on 2 quail chromosomes were genotyped. The F- 33 quails had higher in vivo and postmortem performances and a higher abdominal fat percentage than those of the egg line. Meat from S- 22 quails had a slower collagen maturation (hydroxylysylpyridinoline crosslink/collagen) and a higher ultimate pH. The F1 and F2 generations showed an evident sexual dimorphism, and an additional effect could be due to hybrid heterosis evident in F2. Meat from quails of F1 and F2 generations had a lower IMC amount with a higher degree of collagen maturation compared with parental lines. Two statistically significant QTL have been detected on quail chromosome 2 (CJA02): a QTL with an additive effect (0.50) for IMC in the marker bracket GUJ0037 and GUJ0093; a second QTL with additive (1.32) and dominant (1.91) effects for breast-muscle weight in the marker bracket GUJ0084 and GUJ0073. To our knowledge, this is the first report of a QTL associated with breast-muscle weight and IMC in quail and poultry species, respectively

    Evaluation of radiative transfer schemes for mesoscale model data assimilation: a case study

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    The assimilation of Special Sensor Microwave Imager (SSM/I) data into the Mesoscale Model 5 (MM5) allows for improving the weather forecast. However the results suggested an update the Radiative Transfer Equation (RTE) within the three-dimensional variational (3DVAR) algorithm which is tailored for non rainy conditions only. To this purpose, a new RTE algorithm is tested, in order to account for radiometric response in rainy regions. The new brightness temperatures (<i>T<sub>B</sub></i>) are estimated by using hydrometeor profiles from the MM5 mesoscale model, running with two different microphysical parameterizations. The goodness of the results is assessed by comparing the new <i>T<sub>B</sub></i> with those of the original RTE algorithm in the 3DVAR code and the SSM/I observed data. The results confirm a better reliability of the new RTE compared to the old one

    PEGASO: LONG DURATION BALLOONS FROM NORTH POLE

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    In a joint effort, the Italian Space Agency (ASI) and Andoya Rocket Range (ARR) have initiated the development of a European balloon center in Svalbard, Norway that is an ideal location for performing Long Duration Balloon (LDB) flights. After the identification of the launch location several light balloon flights have been performed since 2003. The 2004 campaign utilized a 10000 mĀ³ balloon produced for the program by Aerostar of Sulfur Springs, Texas USA. This flight lasted 40 days and was an excellent test of the small PEGASO payload, developed (for use in Antarctica) by the National Institute of Geophysics and Volcanology (INGV) with the PNRA (Progetto Nazionale di Ricerche in Antartide) sponsorship. This payload uses an IRIDIUM based bi-directional telemetry system. During summer 2005 two flights have been performed using balloons of the same size. They carried an updated telemetry and a scientific payload which analyzed the magnetic field of the Earth. The Institute of Information Science and Technology (ISTI-CNR) team computed predictions of the balloons trajectories, both before and during flights, as well as statistical evaluations of the seasonal flight windows at the beginning of the ASI LDB program. The 2004 and 2005 missions have been defined to investigate the stratospheric winds structure and they tested the possibility for future heavy LDB flights. The Italian scientific community foresees this kind of missions from 2007-2008 campaigns. Next sections, starting from a general overview of the Italian LDB program, give the description of the Pegaso flights and, in particular, the adopted technical solutions for the on-board and ground-based equipments.PublishedVOLTERRA, PISA1.10. TTC - Telerilevamentoope

    PEGASO: LONG DURATION BALLOONS FROM NORTH POLE

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    In a joint effort, the Italian Space Agency (ASI) and Andoya Rocket Range (ARR) have initiated the development of a European balloon center in Svalbard, Norway that is an ideal location for performing Long Duration Balloon (LDB) flights. After the identification of the launch location several light balloon flights have been performed since 2003. The 2004 campaign utilized a 10000 mĀ³ balloon produced for the program by Aerostar of Sulfur Springs, Texas USA. This flight lasted 40 days and was an excellent test of the small PEGASO payload, developed (for use in Antarctica) by the National Institute of Geophysics and Volcanology (INGV) with the PNRA (Progetto Nazionale di Ricerche in Antartide) sponsorship. This payload uses an IRIDIUM based bi-directional telemetry system. During summer 2005 two flights have been performed using balloons of the same size. They carried an updated telemetry and a scientific payload which analyzed the magnetic field of the Earth. The Institute of Information Science and Technology (ISTI-CNR) team computed predictions of the balloons trajectories, both before and during flights, as well as statistical evaluations of the seasonal flight windows at the beginning of the ASI LDB program. The 2004 and 2005 missions have been defined to investigate the stratospheric winds structure and they tested the possibility for future heavy LDB flights. The Italian scientific community foresees this kind of missions from 2007-2008 campaigns. Next sections, starting from a general overview of the Italian LDB program, give the description of the Pegaso flights and, in particular, the adopted technical solutions for the on-board and ground-based equipments

    Endocytosis of plasma-derived factor V by megakaryocytes occurs via a clathrin-dependent, specific membrane binding event

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    Megakaryocytes were analyzed for their ability to endocytose factor V to define the cellular mechanisms regulating this process. In contrast to fibrinogen, factor V was endocytosed by megakaryocytes derived from CD34 + cells or megakaryocyte-like cell lines, but not by platelets. CD41 + ex vivo -derived megakaryocytes endocytosed factor V, as did subpopulations of the megakaryocyte-like cells MEG-01, and CMK. Similar observations were made for fibrinogen. Phorbol diester-induced megakaryocytic differentiation of the cell lines resulted in a substantial increase in endocytosis of both proteins as compared to untreated cells that did not merely reflect their disparate plasma concentrations. Factor IX, which does not associate with platelets or megakaryocytes, was not endocytosed by any of the cells examined. Endocytosis of factor V by megakaryocytes proceeds through a specific and independent mechanism as CHRF-288 cells endocytosed fibrinogen but not factor V, and the presence of other plasma proteins had no effect on the endocytosis of factor V by MEG-01 cells. Furthermore, as the endocytosis of factor V was also demonstrated to occur through a clathrin-dependent mechanism, these combined data demonstrate that endocytosis of factor V by megakaryocytes occurs via a specific, independent, and most probably receptor-mediated, event.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75473/1/j.1538-7836.2005.01190.x.pd

    Degradation of Internalized Ī±vĪ²5 Integrin Is Controlled by uPAR Bound uPA: Effect on Ī²1 Integrin Activity and Ī±-SMA Stress Fiber Assembly

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    Myofibroblasts (Mfs) that persist in a healing wound promote extracellular matrix (ECM) accumulation and excessive tissue contraction. Increased levels of integrin Ī±vĪ²5 promote the Mf phenotype and other fibrotic markers. Previously we reported that maintaining uPA (urokinase plasminogen activator) bound to its cell-surface receptor, uPAR prevented TGFĪ²-induced Mf differentiation. We now demonstrate that uPA/uPAR controls integrin Ī²5 protein levels and in turn, the Mf phenotype. When cell-surface uPA was increased, integrin Ī²5 levels were reduced (61%). In contrast, when uPA/uPAR was silenced, integrin Ī²5 total and cell-surface levels were increased (2ā€“4 fold). Integrin Ī²5 accumulation resulted from a significant decrease in Ī²5 ubiquitination leading to a decrease in the degradation rate of internalized Ī²5. uPA-silencing also induced Ī±-SMA stress fiber organization in cells that were seeded on collagen, increased cell area (1.7 fold), and increased integrin Ī²1 binding to the collagen matrix, with reduced activation of Ī²1. Elevated cell-surface integrin Ī²5 was necessary for these changes after uPA-silencing since blocking Ī±vĪ²5 function reversed these effects. Our data support a novel mechanism by which downregulation of uPA/uPAR results in increased integrin Ī±vĪ²5 cell-surface protein levels that regulate the activity of Ī²1 integrins, promoting characteristics of the persistent Mf

    Integrin Ī±5Ī²1 Function Is Regulated by XGIPC/kermit2 Mediated Endocytosis during Xenopus laevis Gastrulation

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    During Xenopus gastrulation Ī±5Ī²1 integrin function is modulated in a temporally and spatially restricted manner, however, the regulatory mechanisms behind this regulation remain uncharacterized. Here we report that XGIPC/kermit2 binds to the cytoplasmic domain of the Ī±5 subunit and regulates the activity of Ī±5Ī²1 integrin. The interaction of kermit2 with Ī±5Ī²1 is essential for fibronectin (FN) matrix assembly during the early stages of gastrulation. We further demonstrate that kermit2 regulates Ī±5Ī²1 integrin endocytosis downstream of activin signaling. Inhibition of kermit2 function impairs cell migration but not adhesion to FN substrates indicating that integrin recycling is essential for mesoderm cell migration. Furthermore, we find that the Ī±5Ī²1 integrin is colocalized with kermit2 and Rab 21 in embryonic and XTC cells. These data support a model where region specific mesoderm induction acts through kermit2 to regulate the temporally and spatially restricted changes in adhesive properties of the Ī±5Ī²1 integrin through receptor endocytosis

    Morphological and Chemical Mechanisms of Elongated Mineral Particle Toxicities

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    Much of our understanding regarding the mechanisms for induction of disease following inhalation of respirable elongated mineral particles (REMP) is based on studies involving the biological effects of asbestos fibers. The factors governing the disease potential of an exposure include duration and frequency of exposures; tissue-specific dose over time; impacts on dose persistence from in vivo REMP dissolution, comminution, and clearance; individual susceptibility; and the mineral type and surface characteristics. The mechanisms associated with asbestos particle toxicity involve two facets for each particle's contribution: (1) the physical features of the inhaled REMP, which include width, length, aspect ratio, and effective surface area available for cell contact; and (2) the surface chemical composition and reactivity of the individual fiber/elongated particle. Studies in cell-free systems and with cultured cells suggest an important way in which REMP from asbestos damage cellular molecules or influence cellular processes. This may involve an unfortunate combination of the ability of REMP to chemically generate potentially damaging reactive oxygen species, through surface iron, and the interaction of the unique surfaces with cell membranes to trigger membrane receptor activation. Together these events appear to lead to a cascade of cellular events, including the production of damaging reactive nitrogen species, which may contribute to the disease process. Thus, there is a need to be more cognizant of the potential impact that the total surface area of REMP contributes to the generation of events resulting in pathological changes in biological systems. The information presented has applicability to inhaled dusts, in general, and specifically to respirable elongated mineral particles
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