42 research outputs found

    Interlinkages of Land Degradation, Marginality and Land Use Cover Change in Kenya : Development of an interdisciplinary framework using remote sensing and GIS

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    Land degradation (LD) is a global problem affecting and being affected by socio-ecological systems. In this thesis the interlinkages of LD, marginality and land use cover change (LUCC) in Kenya based on remote sensing and geographic information systems (GIS) are analyzed. By combining biophysical and socio-economic data we obtain a deeper understanding of internal dynamics and their relationship to processes of decreasing productivity within a coupled Human-Environment System (HES). The simultaneous use of quantitative and qualitative methods supports insights in different disciplines. LD stands for the decrease of soil fertility and, hence, land productivity. Marginality is defined as the root cause of poverty but goes beyond the solely economic perspective of poverty measurement. LUCC represents another interdisciplinary concept where LC refers to the land surface and its biophysical determinants which can be detected with remote sensing while land use (LU) includes an active component referring to activities on land by human impact. The study was conducted on two different scales: the national scale, the country Kenya, and a local scale focusing on western Kenya. With census data and household survey information the socio-economic perspective was presented while biophysical assessment on LD and LUCC was conducted via remote sensing imagery. Time series analysis of vegetation information derived from remotely sensed imagery – NDVI and EVI – lead to the analysis of trends of land productivity from 2001 to 2011. In the national study, based on five indicator groups, different dimensions of marginality such as health, education, access to infrastructure and information but also economy could be analyzed. A set of eight indicators was detected that explains decreasing productivity trends with the use of exploratory regression and ordinary least square regression (OLS) on the national scale. Explaining decreasing productivity trends on the local level using household information for 42 villages and their respective acting scopes made obvious that also qualitative information is needed to validate and interpret results correctly. Trigger events such as the post-election violence in 2007 and 2008, and the world economy crisis in 2008 had a significant impact on decreasing productivity trends in 2009 in the local study area. The national and the local study both showed that variables explaining decreasing and stable productivity trends are in close relationship while increasing productivity is influenced by a different set of variables. Therefore, with regard to the concept of land degradation neutrality (LDN) stable productivity trends need to be taken into account for future research. Identification of biophysical and socio-economic variables influencing productivity trends helps to get a better understanding of coupled HES. The interdisciplinary approach of this study is path leading for the development of food security strategies. Validation of the here presented results on the respective spatial scale can be used to identify areas where a need for action is required to stop ongoing productivity decrease and finally stabilize yields

    The Economics of Desertification, Land Degradation, and Drought; Toward an Integrated Global Assessment

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    Land degradation has not been comprehensively addressed at the global level or in developing countries. A suitable economic framework that could guide investments and institutional action is lacking. This study aims to overcome this deficiency and to provide a framework for a global assessment based on a consideration of the costs of action versus inaction regarding desertification, land degradation, and drought (DLDD). Most of the studies on the costs of land degradation (mainly limited to soil erosion) give cost estimates of less than 1 percent up to about 10 percent of the agricultural gross domestic product (GDP) for various countries worldwide. But the indirect costs of DLDD on the economy (national income), as well as their socioeconomic consequences (particularly poverty impacts), must be accounted for, too. Despite the numerous challenges, a global assessment of the costs of action and inaction against DLDD is possible, urgent, and necessary. This study provides a framework for such a global assessment and provides insights from some related country studies.Agricultural Finance, Crop Production/Industries, Environmental Economics and Policy, Land Economics/Use, Resource /Energy Economics and Policy,

    Spectroscopija 125Te (n,γ), (d,p) i (3He,α) reakcijama

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    Single γ-ray spectra and γγ-coincidences, following thermal neutron capture in 124Te, were measured with semiconductor detectors at the light-water reactor LWR - 15 at Řež. Intensities of g transitions in 125Te were normalized using the absolute intensity of 7.8% of the 6620 keV line in 36Cl. The high resolution (d,p) measurements were performed with 17 MeV deuterons, using the Q3D spectrograph at two scattering angles of 15° and 30°. Spectra were recorded in the range up to 3.3 MeV and calibrated using the proton peaks with l =1, and the corresponding level energies were determined in the thermal neutron capture reaction. The (3He,α) experiment was carried out with a 32 MeV He beam at the angle of 10°. The spectrum was recorded in one run by means of a large detector in a range up to approximately 4.7 MeV. The absolute intensities were determined by measuring the total beam current.Mjerili su se izravni γ- i sudesni γ-γ-spektri nakon uhvata termičkih neutrona u 124Te. Mjerenja (d,p) reakcija visokog razlučivanja na toj jezgri izvela su se s deuteronima 17 MeV na kutovima od 15° i 30° , pomoću Q3D spektrografa. Također se mjerio spektar u reakciji (3He,α) na 10° . Na osnovi tih mjerenja utvrđena su mnoga nova stanja 125Te na energijama uzbude do oko 4.5 MeV. Razlika grananja 403/443 keV iz izravnih i sudesnih γ-spektara ukazuje na jaku primjesu E2 u primarnom prijelazu od 6125 keV

    Spectroscopija 125Te (n,γ), (d,p) i (3He,α) reakcijama

    Get PDF
    Single γ-ray spectra and γγ-coincidences, following thermal neutron capture in 124Te, were measured with semiconductor detectors at the light-water reactor LWR - 15 at Řež. Intensities of g transitions in 125Te were normalized using the absolute intensity of 7.8% of the 6620 keV line in 36Cl. The high resolution (d,p) measurements were performed with 17 MeV deuterons, using the Q3D spectrograph at two scattering angles of 15° and 30°. Spectra were recorded in the range up to 3.3 MeV and calibrated using the proton peaks with l =1, and the corresponding level energies were determined in the thermal neutron capture reaction. The (3He,α) experiment was carried out with a 32 MeV He beam at the angle of 10°. The spectrum was recorded in one run by means of a large detector in a range up to approximately 4.7 MeV. The absolute intensities were determined by measuring the total beam current.Mjerili su se izravni γ- i sudesni γ-γ-spektri nakon uhvata termičkih neutrona u 124Te. Mjerenja (d,p) reakcija visokog razlučivanja na toj jezgri izvela su se s deuteronima 17 MeV na kutovima od 15° i 30° , pomoću Q3D spektrografa. Također se mjerio spektar u reakciji (3He,α) na 10° . Na osnovi tih mjerenja utvrđena su mnoga nova stanja 125Te na energijama uzbude do oko 4.5 MeV. Razlika grananja 403/443 keV iz izravnih i sudesnih γ-spektara ukazuje na jaku primjesu E2 u primarnom prijelazu od 6125 keV

    Decreased levels of BAG3 in a family with a rare variant and in idiopathic dilated cardiomyopathy.

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    The most common cause of dilated cardiomyopathy and heart failure (HF) is ischemic heart disease; however, in a third of all patients the cause remains undefined and patients are diagnosed as having idiopathic dilated cardiomyopathy (IDC). Recent studies suggest that many patients with IDC have a family history of HF and rare genetic variants in over 35 genes have been shown to be causative of disease. We employed whole-exome sequencing to identify the causative variant in a large family with autosomal dominant transmission of dilated cardiomyopathy. Sequencing and subsequent informatics revealed a novel 10-nucleotide deletion in the BCL2-associated athanogene 3 (BAG3) gene (Ch10:del 121436332_12143641: del. 1266_1275 [NM 004281]) that segregated with all affected individuals. The deletion predicted a shift in the reading frame with the resultant deletion of 135 amino acids from the C-terminal end of the protein. Consistent with genetic variants in genes encoding other sarcomeric proteins there was a considerable amount of genetic heterogeneity in the affected family members. Interestingly, we also found that the levels of BAG3 protein were significantly reduced in the hearts from unrelated patients with end-stage HF undergoing cardiac transplantation when compared with non-failing controls. Diminished levels of BAG3 protein may be associated with both familial and non-familial forms of dilated cardiomyopathy

    Pleiotropic effects in Eya3 knockout mice

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    <p>Abstract</p> <p>Background</p> <p>In <it>Drosophila</it>, mutations in the gene <it>eyes absent </it>(<it>eya</it>) lead to severe defects in eye development. The functions of its mammalian orthologs <it>Eya1-4 </it>are only partially understood and no mouse model exists for <it>Eya3</it>. Therefore, we characterized the phenotype of a new <it>Eya3 </it>knockout mouse mutant.</p> <p>Results</p> <p>Expression analysis of <it>Eya3 </it>by <it>in-situ </it>hybridizations and β-Gal-staining of <it>Eya3 </it>mutant mice revealed abundant expression of the gene throughout development, e.g. in brain, eyes, heart, somites and limbs suggesting pleiotropic effects of the mutated gene. A similar complex expression pattern was observed also in zebrafish embryos.</p> <p>The phenotype of young adult <it>Eya3 </it>mouse mutants was systematically analyzed within the German Mouse Clinic. There was no obvious defect in the eyes, ears and kidneys of <it>Eya3 </it>mutant mice. Homozygous mutants displayed decreased bone mineral content and shorter body length. In the lung, the tidal volume at rest was decreased, and electrocardiography showed increased JT- and PQ intervals as well as decreased QRS amplitude. Behavioral analysis of the mutants demonstrated a mild increase in exploratory behavior, but decreased locomotor activity and reduced muscle strength. Analysis of differential gene expression revealed 110 regulated genes in heart and brain. Using real-time PCR, we confirmed <it>Nup155 </it>being down regulated in both organs.</p> <p>Conclusion</p> <p>The loss of <it>Eya3 </it>in the mouse has no apparent effect on eye development. The wide-spread expression of <it>Eya3 </it>in mouse and zebrafish embryos is in contrast to the restricted expression pattern in <it>Xenopus </it>embryos. The loss of <it>Eya3 </it>in mice leads to a broad spectrum of minor physiological changes. Among them, the mutant mice move less than the wild-type mice and, together with the effects on respiratory, muscle and heart function, the mutation might lead to more severe effects when the mice become older. Therefore, future investigations of <it>Eya3 </it>function should focus on aging mice.</p

    A large scale hearing loss screen reveals an extensive unexplored genetic landscape for auditory dysfunction

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    The developmental and physiological complexity of the auditory system is likely reflected in the underlying set of genes involved in auditory function. In humans, over 150 non-syndromic loci have been identified, and there are more than 400 human genetic syndromes with a hearing loss component. Over 100 non-syndromic hearing loss genes have been identified in mouse and human, but we remain ignorant of the full extent of the genetic landscape involved in auditory dysfunction. As part of the International Mouse Phenotyping Consortium, we undertook a hearing loss screen in a cohort of 3006 mouse knockout strains. In total, we identify 67 candidate hearing loss genes. We detect known hearing loss genes, but the vast majority, 52, of the candidate genes were novel. Our analysis reveals a large and unexplored genetic landscape involved with auditory function

    A comprehensive and comparative phenotypic analysis of the collaborative founder strains identifies new and known phenotypes.

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    The collaborative cross (CC) is a large panel of mouse-inbred lines derived from eight founder strains (NOD/ShiLtJ, NZO/HILtJ, A/J, C57BL/6J, 129S1/SvImJ, CAST/EiJ, PWK/PhJ, and WSB/EiJ). Here, we performed a comprehensive and comparative phenotyping screening to identify phenotypic differences and similarities between the eight founder strains. In total, more than 300 parameters including allergy, behavior, cardiovascular, clinical blood chemistry, dysmorphology, bone and cartilage, energy metabolism, eye and vision, immunology, lung function, neurology, nociception, and pathology were analyzed; in most traits from sixteen females and sixteen males. We identified over 270 parameters that were significantly different between strains. This study highlights the value of the founder and CC strains for phenotype-genotype associations of many genetic traits that are highly relevant to human diseases. All data described here are publicly available from the mouse phenome database for analyses and downloads
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