50 research outputs found

    Collection and analysis of radar rainfall and satellite data for the Darwin TRMM experiment

    Get PDF
    The following subject areas are covered: video cloud camera (purpose, design, operation, data); special observing periods (SOP-2, SOP 2.5 - an extension of SOP-2); Garand algorithm; and warm rain

    Application of lightning data to satellite-based rainfall estimation

    Get PDF
    Information on lightning may improve rain estimates made from infrared images of a geostationary satellite. We address this proposition through a case from the Cooperative Huntsville Meteorological Experiment (COHMEX). During the afternoon and evening of 13 July 1986 waves of showers and thunderstorms developed over and near the lower Tennessee River Valley. For the shower and thunderstorm region within 200 km of the National Weather Service radar at Nashville, Tennessee, we measure cold-cloud area in a sequence of GOES infrared images covering all but the end of the shower and thunderstorm period. From observations of the NASA/Marshall direction-finding network in this small domain, we also count cloud-to-ground lightning flashes and, from scans of the Nashville radar, we calculate volume rain flux. Using a modified version of the Williams and Houze scheme, over an area within roughly 240 km of the radar (the large domain), we identify and track cold cloud systems. For these systems, over the large domain, we measure area and count flashes; over the small domain, we calculate volume rain flux. For a temperature threshold of 235K, peak cloud area over the small domain lags both peak rain flux and peak flash count by about four hours. At a threshold of 226K, the lag is about two hours. Flashes and flux are matched in phase. Over the large domain, nine storm systems occur. These range in size from 300 to 60,000 km(exp 2); in lifetime, from about 2 1/2 h to 6 h or more. Storm system area lags volume rain flux and flash count; nevertheless, it is linked with these variables. In essential respects the associations were the same when clouds were defined by a threshold of 226K. Tentatively, we conclude that flash counts complement infrared images in providing significant additional information on rain flux

    Use of microwave satellite data to study variations in rainfall over the Indian Ocean

    Get PDF
    The University of Wisconsin Space Science and Engineering Center mapped rainfall over the Indian Ocean using a newly developed Scanning Multichannel Microwave Radiometer (SMMR) rain-retrieval algorithm. The short-range objective was to characterize the distribution and variability of Indian Ocean rainfall on seasonal and annual scales. In the long-range, the objective is to clarify differences between land and marine regimes of monsoon rain. Researchers developed a semi-empirical algorithm for retrieving Indian Ocean rainfall. Tools for this development have come from radiative transfer and cloud liquid water models. Where possible, ground truth information from available radars was used in development and testing. SMMR rainfalls were also compared with Indian Ocean gauge rainfalls. Final Indian Ocean maps were produced for months, seasons, and years and interpreted in terms of historical analysis over the sub-continent

    Four-Dimensional Consciousness

    Full text link

    Testicular Lumicrine Factors Regulate ERK, STAT, and NFKB Pathways in the Initial Segment of the Rat Epididymis to Prevent Apoptosis1

    No full text
    The initial segment of the epididymis is vital for male fertility; therefore, it is important to understand the mechanisms that regulate this important region. Deprival of testicular luminal fluid factors/lumicrine factors from the epididymis results in a wave of apoptosis in the initial segment. In this study, a combination of protein array and microarray analyses was used to examine the early changes in downstream signal transduction pathways following loss of lumicrine factors. We discovered the following cascade of events leading to the loss of protection and eventual apoptosis: in the first 6 h after loss of lumicrine factors, down-regulation of the ERK pathway components was observed at the mRNA expression and protein activity levels. Microarray analysis revealed that mRNA levels of several key components of the ERK pathway, Dusp6, Dusp5, and Etv5, decreased sharply, while the analysis from the protein array revealed a decline in the activities of MAP2K1/2 and MAPK1. Immunostaining of phospho-MAPK3/1 indicated that down-regulation of the ERK pathway was specific to the epithelial cells of the initial segment. Subsequently, after 12 h of loss of lumicrine factors, levels of mRNA expression of STAT and NFKB pathway components increased, mRNA levels of several genes encoding cell cycle inhibitors increased, and levels of protein expression of several proapoptotic phosphatases increased. Finally, after 18 h of loss of protection from lumicrine factors, apoptosis was observed. In conclusion, testicular lumicrine factors protect the cells of the initial segment by activating the ERK pathway, repressing STAT and NFKB pathways, and thereby preventing apoptosis

    Novel androgen-induced activity of an antimicrobial beta-defensin: Regulation of Wolffian duct morphogenesis

    No full text
    The Wolffian duct (WD) undergoes morphological changes induced by androgens to form the epididymis, which is an organ essential for sperm maturation. Androgen action in WD epithelium involves paracrine factors of mesenchymal origin that function by still poorly understood mechanisms. Here we studied the antimicrobial beta-defensin SPAGIIC as a new player in duct morphogenesis, localized prenatally in the WD mesenchyme. Organotypic culture of rat WDs and tissues from Androgen Receptor (AR) knockout mice (ARKO) were used. Our results show that androgen/AR signaling differentially regulated SPAGIIC expression at mRNA and protein levels in the developing WD. WDs incubated with recombinant human SPAGI1C were shorter and less coiled as a result of reduced epithelial cell proliferation, but not increased apoptosis. Our results suggested beta-defensin SPAGIIC as an androgen-target required for WD morphogenesis. This highlights the multifunctional repertoire of the beta-defensin protein family and their potential contribution to the in utero environment that determines male reproductive success. (C) 2016 Elsevier Ireland Ltd. All rights reserved.Conselho Nacional de Desenvolvimento Cientifico e TecnologicoSao Paulo Research Foundation (FAPESP)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES fellowship)National Institutes of Health Eunice Kennedy Shriver NICHD (NIH)UK MRCUniv Fed Sao Paulo, Escola Paulista Medicina, Dept Pharmacol, Sect Expt Endocrinol, Rua 03 maio 100,INFAR,Vila Clementino, BR-04044020 Sao Paulo, SP, BrazilUniv Edinburgh, MRC Ctr Reprod Hlth, Queens Med Res Inst, Edinburgh, Midlothian, ScotlandUniv Virginia, Sch Med, Dept Cell Biol, Charlottesville, VA USAUniv Fed Sao Paulo, Escola Paulista Medicina, Dept Pharmacol, Sect Expt Endocrinol, Rua 03 maio 100,INFAR,Vila Clementino, BR-04044020 Sao Paulo, SP, BrazilCNPq: 401932/2013-3CNPq: 150066/2016-3CNPq: 101955/2015-4CNPq: 308349/2010-5FAPESP: 2010/52711-0FAPESP: 2009/14649-3National Institutes of Health Eunice Kennedy Shriver NICHD (NIH):R01-HD069654UK MRC: MR/N002970/1Web of Scienc
    corecore