918 research outputs found

    Permafrost aggradation reduces peatland methane fluxes during the Holocene

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    Methane emissions from northern high latitude wetlands are one of the largest natural sources of atmospheric methane, contributing an estimated 20% of the natural terrestrial methane emissions to the atmosphere. Methane fluxes vary among wetland types and are generally higher in peatlands, wetlands with > 40 cm of organic soil, than in wetlands with mineral soils. However, permafrost aggradation in peatlands reduces methane fluxes through the drying of the peat surface, which can decrease both methane production and increase methane oxidation within the peat. We reconstruct methane emissions from peatlands during the Holocene using a synthesis of peatland environmental classes determined from plant macrofossil records in peat cores from > 250 sites across the pan-arctic. We find methane emissions from peatlands decreased by 20% during the Little Ice Age due to the aggradation of permafrost within peatlands during this period. These bottom-up estimates of methane emissions for the present day are in agreement with other regional estimates and are significantly lower than the peak in peatland methane emissions 1300 years before present. Our results indicate that methane emissions from high latitude wetlands have been an important contributor to atmospheric methane concentrations during the Holocene and will likely change in the future with permafrost thaw

    <Material> Examples of Betriebsordnung in West Germany

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    Background: There is an ongoing search for biomarkers in psychiatry, for example, as diagnostic tools or predictors of treatment response. The neurotrophic factor S100 calcium binding protein B (S100B) has been discussed as a possible predictor of antidepressant response in patients with major depression, but also as a possible biomarker of an acute depressive state. The aim of the present study was to study the association of serum S100B levels with antidepressant treatment response and depression severity in melancholically depressed inpatients. Methods: After a wash-out period of 1 week, 40 inpatients with melancholic depression were treated with either venlafaxine or imipramine. S100B levels and Hamilton Depression Rating Scale (HAM-D) scores were assessed at baseline, after 7 weeks of treatment, and after 6 months. Results: Patients with high S100B levels at baseline showed a markedly better treatment response defined as relative reduction in HAM-D scores than those with low baseline S100B levels after 7 weeks (P=.002) and 6 months (P=.003). In linear regression models, S100B was a significant predictor for treatment response at both time points. It is of interest to note that nonresponders were detected with a predictive value of 85% and a false negative rate of 7.5%. S100B levels were not associated with depression severity and did not change with clinical improvement. Conclusions: Low S100B levels predict nonresponse to venlafaxine and imipramine with high precision. Future studies have to show which treatments are effective in patients with low levels of S100B so that this biomarker will help to reduce patients' burden of nonresponding to frequently used antidepressants

    Type 2 diabetes monocyte microrna and mrna expression

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    There is increasing evidence that inflammatory macrophages in adipose tissue are involved in insulin resistance of type 2 diabetes (T2D). Due to a relative paucity of data on circulating monocytes in T2D, it is unclear whether the inflammatory changes of adipose tissue macrophages are reflected in these easily accessible cells. Objective To study the expression pattern of microRNAs and mRNAs related to inflammation in T2D monocytes. Design A microRNA finding study on monocytes of T2D patients and controls using array profiling was followed by a quantitative Real Time PCR (qPCR) study on monocytes of an Ecuadorian validation cohort testing the top over/under-expressed microRNAs. In addition, monocytes of the validation cohort were tested for 24 inflammation-related mRNAs and 2 microRNAs previously found deregulated in (auto)-inflammatory monocytes. Results In the finding study, 142 significantly differentially expressed microRNAs were identified, 15 having the strongest power to discriminate T2D patients from controls (sensitivity 66%, specificity 90%). However, differences in expression of these microRNAs between patients and controls were small. On the basis of >1.4 or <0.6-fold change expression 5 microRNAs were selected for further validation. One microRNA (miR-34c-5p) was validated as significantly over-expressed in T2D monocytes. In addition, we found over expression of 3 mRNAs (CD9, DHRS3 and PTPN7) in the validation cohort. These mRNAs are important for cell morphology, adhesion, shape change, and cell differentiation. Classical inflammatory genes (e.g. TNFAIP3) were only over-expressed in monocytes of patients with normal serum lipids. Remarkably, in dyslipidemia, there was a reduction in the expression of inflammatory genes (e.g. ATF3, DUSP2 and PTGS2). Conclusions The expression profile of microRNAs/mRNAs in monocytes of T2D patients indicates an altered adhesion, differentiation, and shape change potential. Monocyte inflammatory activation was only found in patients with normal serum lipids. Abnormal lipid values coincided with a reduced monocyte inflammatory state. Copyright

    REDUCED TILLAGE AND COVER CROPS IN ORGANIC ARABLE SYSTEMS PRESERVES WEED DIVERSITY WITHOUT JEOPARDISING CROP YIELD

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    One of the objectives of the TILMAN-ORG Project is to improve weed management under conservation agriculture (reduced tillage and/or cover crops) in organic arable systems. The shift from ploughing to conservation agriculture should not only maintain crop yield but possibly improve weed community diversity. This paper summarises the results on (1) weed abundance, (2) weed diversity and (3) crop yield obtained in the first year of the project (2012) in 13 trials scattered across Europe

    Study on inflammation-related genes and microRNAs, with special emphasis on the vascular repair factor HGF and miR-574-3p, in monocytes and serum of patients with T2D

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    Background: Recently, we reported signs of inflammation (raised IL-8, reduced miR-146a) and signs of vascular repair (raised HGF) in the serum of Ecuadorian patients with type 2 diabetes (T2

    Petrographical and geochemical characterization and deformation conditions of the San Cristóbal pluton, Sierra de Velasco, La Rioja, Argentina

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    El plutón San Cristóbal constituye un cuerpo granítico de 35 km2 que aflora en el extremo sudeste de la Sierra de Velasco, situada al oeste de la ciudad de La Rioja, Argentina. Está formado por monzogranitos y sienogranitos con escasas granodioritas, de texturas equigranulares de grano medio a fino a ligeramente porfíricas. La asociación mineral es cuarzo + microclino + plagioclasa + biotita ± moscovita + circón + apatito + magnetita. Contiene enclaves magmáticos máficos de composición diorítica a tonalítica. El granito fue afectado en su parte media y este por una zona de cizalla, formada por milonitas que integran la Faja Milonítica Sur, de rumbo NNO-SSE. La roca de caja se reconoce por xenolitos de esquistos y cuarcitas en facies esquistos verdes, y septos de corneanas con la paragénesis feldespato potásico - cordierita - biotita ± sillimanita. Los granitos son calcoalcalinos, débil a moderadamente peraluminosos, emplazados en un ambiente de arco magmático continental desarrollado en el borde occidental de Gondwana durante el Paleozoico Inferior. La profundidad de emplazamiento del plutón estaría en el orden de los 12 km.The San Cristóbal pluton is a 35 km2 granitic body that outcrops at the southestern tip of the Sierra de Velasco, located west of La Rioja city, Argentina. It is formed by monzogranites and syenogranites, together with scarce granodiorites, with medium to fine-grained, equigranular to slightly porphyritic textu- res. Their mineral assemblage consists of quartz + microcline + plagioclase + biotite ± muscovite + zir- con + apatite + magnetite. The granite contains dioritic to tonalitic mafic enclaves. The central and eas- tern parts of the granite have been deformed by the NNW-SSE trending South Mylonitic shear zone for- med by mylonitic rocks. The metamorphic host-rock is represented by scarce greenschist facies xeno- liths and hornfels with the high T/P assemblage K-feldspar – cordierite – biotite ± sillimanite. The grani- tes are calc-alkaline, weak- to moderately peraluminous, and formed as part of a continental magmatic arc developed along the active margin of western Gondwana during the Early Paleozoic. The depth of emplacement of the San Cristóbal pluton is estimated at ~12 km.Fil: Bellos, Laura Iudith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Toselli, Alejandro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Rossi, J. N.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Grosse, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: de la Rosa, J. D.. Universidad de Huelva; EspañaFil: Castro, A.. Universidad de Huelva; Españ

    The impact of nitric oxide toxicity on the evolution of the glutathione transferase superfamily: A proposal for an evolutionary driving force

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    Background: Why do ancestral GSTs utilize cysteine/serine as catalytic residues, whereas more recently evolved GSTs utilize tyrosine? Results: Only the more recently evolved GSTs display enough affinity to bind and make harmless the toxic DNDGIC (a natur

    Vulnerability of high latitude soil organic carbon in North America to disturbance

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    This synthesis addresses the vulnerability of the North American high-latitude soil organic carbon (SOC) pool to climate change. Disturbances caused by climate warming in arctic, subarctic, and boreal environments can result in significant redistribution of C among major reservoirs with potential global impacts. We divide the current northern high-latitude SOC pools into (1) near-surface soils where SOC is affected by seasonal freeze-thaw processes and changes in moisture status, and (2) deeper permafrost and peatland strata down to several tens of meters depth where SOC is usually not affected by short-term changes. We address key factors (permafrost, vegetation, hydrology, paleoenvironmental history) and processes (C input, storage, decomposition, and output) responsible for the formation of the large high-latitude SOC pool in North America and highlight how climate-related disturbances could alter this pool\u27s character and size. Press disturbances of relatively slow but persistent nature such as top-down thawing of permafrost, and changes in hydrology, microbiological communities, pedological processes, and vegetation types, as well as pulse disturbances of relatively rapid and local nature such as wildfires and thermokarst, could substantially impact SOC stocks. Ongoing climate warming in the North American high-latitude region could result in crossing environmental thresholds, thereby accelerating press disturbances and increasingly triggering pulse disturbances and eventually affecting the C source/sink net character of northern high-latitude soils. Finally, we assess postdisturbance feedbacks, models, and predictions for the northern high-latitude SOC pool, and discuss data and research gaps to be addressed by future research

    Propiedades psicométricas del Hopkins Symptom Checklist (HSCL-11) en Argentina: Un instrumento para monitoreo y feedback en psicoterapia

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    We failed to find brief instruments validated in Argentina to explore and monitor psychological symptoms from psychotherapy patients. This paper presents the Argentinian adaptation of the Hopkins Symptoms Checklist (HSCL-11) and analyzes its psychometric properties. A sample of 356 participants completed the HSCL-11 adaptation, along with other measures of depression, anxiety, and well-being. We analyzed Cronbach’s alpha and item-total correlations adjusted. We ran confirmatory factor analysis, correlations among the measures, and&nbsp; examined differences in HSCL-11 between subjects who were psychotherapy patients and those who were not. We found evidence of adequate internal consistency and item homogeneity, as well as construct validity, concurrent validity, and criterion validity. Results showed evidence of reliability and validity for the HSCL-11 Argentinian adaptation, suggesting that it might represent a meaningful resource for the evaluation and treatment of mental disorders in Argentina.No se han encontrado instrumentos breves válidos en Argentina para monitorear sintomatología psicológica en psicoterapia. Este trabajo presenta la adaptación argentina del Hopkins Symptoms Checklist (HSCL-11) y estudia sus propiedades psicométricas. Una muestra de 356 participantes completó la adaptación del HSCL-11 junto con medidas de depresión, ansiedad y bienestar. Se computaron el coeficiente alfa de Cronbach y correlaciones ítem-total corregidas. Se realizó un análisis factorial confirmatorio, se estudiaron sus correlaciones con las otras medidas y se analizaron las diferencias en HSCL-11 entre pacientes y no pacientes de terapia. Se observaron evidencias de adecuada consistencia interna y homogeneidad de ítems, así como también de validez de constructo, validez concurrente y validez de criterio. Los resultados mostraron evidencias deconfiabilidad y validez de la versión argentina del HSCL-11, sugiriendo que podría representar un instrumento valioso para la evaluación y el tratamiento de patologías mentales en el país
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