2,217 research outputs found

    Towards regionalisation of soils in Northern Thailand and consequences for mapping approaches and upscaling procedures

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    Ziel dieser Arbeit war, die Grundprinzipien der Bodengenese und Bodenverteilung in Nordthailand zu erfassen, um damit eine Konzeptkartierung zu ermöglichen. Des Weiteren werden verschiedene KartieransĂ€tze hinsichtlich Ihrer Eignung fĂŒr verschiedene Skalen und Fragestellungen ĂŒberprĂŒft. DarĂŒber hinaus wurde das Potential des lokalen Wissens hinsichtlich Bodenkartierung and Landnutzungsplanung untersucht. Um die Petrographie von Nordwestthailand im Wesentlichen abzudecken, wurden drei petrographisch unterschiedliche Untersuchungsstandorte ausgewĂ€hlt und in Bezug auf Petrographie, Bodeninventar, physikalischen und chemischen Eigenschaften untersucht. ZusĂ€tzlich wurde das lokale Bodenwissen der jeweilig ansĂ€ssigen Bevölkerung erhoben. Außerdem wurden fĂŒr jedes Gebiet zahlreiche thematische Karten erstellt. Diese stellen die rĂ€umliche VariabilitĂ€t von Geologie, Bodentypen, einigen Bodeneigenschaften und auf lokalem Wissen basierenden Bodentypen dar. Die Bodenkartierung der auf WRB basierenden Bodenklassifikation wurde mit vier verschiedenen AnsĂ€tzen durchgefĂŒhrt, deren Effizienz und Genauigkeit getestet werden sollten. Die intensive Bodenkartierung basiert auf Transektkartierung, gitterbasierter randomisierter Kartierung, sowie auf zusĂ€tzlichen Untersuchungspunkten fĂŒr den Bereich erhöhter VariabilitĂ€t von Böden und Ausgangsgestein. Alle auf der intensiven Bodenkartierung basierenden Karten zeichnen sich durch höchste Beprobungsdichte und maximalen Informationsgehalt aus. Daher wurden diese Karten als Referenz fĂŒr die anderen KartieransĂ€tze herangezogen.The purpose of this study was to identify the key factors of soil formation and distribution in North-western Thailand in order to enable predictive mapping. Further objectives were to investigate different soil mapping approaches, regarding their suitability for specific areas and scales and to assess the potential of local (soil) knowledge for soil mapping and land use planning. In order to cover the essential petrographic inventory of North-western Thailand three different petrographic areas were selected. The investigated topics were petrographic diversity, spatial organisation of soils and variability of their physical and chemical properties, as well as local soil knowledge of farmers in the respective areas. In addition thematic maps were generated comprising geology, WRB soil groups, and different soil properties. Soil mapping was carried out by using four different methods, the intensive mapping approach, maximum likelihood method, randomised grid cell approach, as well as elicitation of local knowledge. The intensive mapping approach comprised transect investigations, investigation points of the randomised grid cell approach, and additional investigation points, which were selected for areas with increased soil and petrographic variability. All maps based on the intensive mapping approach contained the highest sampling point density and maximum amount of information. These maps were used as a reference for the other mapping approaches applied here

    Internationale Klassifikation von Gesteinen nach pedologischen Gesichtspunkten

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    Im Rahmen des europĂ€ischen eSOTER Projekts (www.esoter.net) werden neue Me-thoden fĂŒr die bodenkundlich ausgerichtete Abgrenzung von Landschaften mit GIS-MoÂŹdellen entwickelt. Diese basieren im Wesentlichen auf digitalen Relief- und Lithologiedaten. Der Schwerpunkt der BGR-Arbeiten liegt auf der einheitlichen Erfas-sung und Darstellung von GesteinsinformaÂŹtionen nach pedologischen Aspekten. Mit diesen AktivitĂ€ten unterstĂŒtzt die BGR auch ein Projekt des globalen UmweltĂŒberwa-chungssystems GEOSS (Task „Global Soil Data“). Die BGR stellt nunmehr eine Über-arbeitung der FAO-AusgangsgesteinsklassiÂŹfikation zur Diskussion

    Reliefanalyse als Mittel fĂŒr eine objektivere Abgrenzung von Bodengroßlandschaften

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    Bodengroßlandschaften (BGL) und Bodenregionen (BR) sind als hierarchische Gliederungsebene fĂŒr die Erstellung klein- und mittelmaßstĂ€biger Bodenkarten von Bedeutung. Dabei sind BGL und BR wichtige Hilfsmittel fĂŒr eine systematische Integration von Bodendaten unterschiedlicher Herkunft, z.B. aus verschiedenen BundeslĂ€ndern oder bei der Erstellung einer Europaweit einheitlichen BodenĂŒbersichtskarte. Zunehmend wichtig werden Grenzen von BGL und BR auch bei der Kopplung von Bodeninformationen aus Karten und Inventurdaten mit Modellszenarien, wie sie z.B. bei der Bewertung von KohlenstoffvorrĂ€ten in Waldböden (ZIRLEWAGEN & VON WILPERT 2010) oder bei der AbschĂ€tzung von Folgen des Klimawandels benötigt werden. Solche Modelle liefern hĂ€ufig bessere Ergebnisse, wenn eine landschaftsspezifische Eichung erfolgen kann. Die Definitionen von BGL, wie sie gegenwĂ€rtig in der Bodenkundlichen Kartieranleitung (KA5) zu finden sind, werden diesen Anforderungen nicht gerecht. Zum einen sind die Definitionen hĂ€ufig nicht eindeutig und lassen dem Bearbeiter bei der Abgrenzung viel Spielraum. Zum anderen ist der methodische Ansatz problematisch, BGL zunĂ€chst "aus kleinmaßstĂ€bigen Grundlagendaten "top-down" abzugrenzen. GegenwĂ€rtig werden daher bei der BGR VorschlĂ€ge fĂŒr eine verbesserte Definierung und Abgrenzung der BGL als Diskussionsgrundlage entworfen. Dabei werden u.a. auch Möglichkeiten der GIS-gestĂŒtzten Analyse von digitalen Höhenmodelldaten untersucht, um den reliefbezogenen Anteil der BGL-Grenzen zu modellieren

    Oral and Intravenous Itraconazole for Systemic Fungal Infections in Neutropenic Haematological Patients: Meeting Report

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    Effective prevention, or treatment, of invasive fungal infection in the neutropenic patient has hitherto been unsatisfactory because of either an inadequate anti-fungal spectrum of the agent or important toxicity. Itraconazole is effective against a broad spectrum of the opportunistic pathogens seen in Europe and North America. Prior problems with absorption, e.g. in the marrow transplant recipient, have been overcome with the introduction of an oral solution and an i.v. preparation. The deliberations of an expert meeting held in June, 1998 include recommendations on which patient requires one of these new preparations based on clinical trials, the dose and route. Important drug interactions are also detailed.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugÀnglich

    The price of tumor control

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    Ipilimumab, a cytotoxic T-lymphocyte antigen-4 (CTLA-4) blocking antibody, has been approved for the treatment of metastatic melanoma and induces adverse events (AE) in up to 64% of patients. Treatment algorithms for the management of common ipilimumab-induced AEs have lead to a reduction of morbidity, e.g. due to bowel perforations. However, the spectrum of less common AEs is expanding as ipilimumab is increasingly applied. Stringent recognition and management of AEs will reduce drug-induced morbidity and costs, and thus, positively impact the cost-benefit ratio of the drug. To facilitate timely identification and adequate management data on rare AEs were analyzed at 19 skin cancer centers. Patient files (n = 752) were screened for rare ipilimumab-associated AEs. A total of 120 AEs, some of which were life-threatening or even fatal, were reported and summarized by organ system describing the most instructive cases in detail. Previously unreported AEs like drug rash with eosinophilia and systemic symptoms (DRESS), granulomatous inflammation of the central nervous system, and aseptic meningitis, were documented. Obstacles included patientƛ delay in reporting symptoms and the differentiation of steroid-induced from ipilimumab-induced AEs under steroid treatment. Importantly, response rate was high in this patient population with tumor regression in 30.9% and a tumor control rate of 61.8% in stage IV melanoma patients despite the fact that some patients received only two of four recommended ipilimumab infusions. This suggests that ipilimumab-induced antitumor responses can have an early onset and that severe autoimmune reactions may reflect overtreatment. The wide spectrum of ipilimumab-induced AEs demands doctor and patient awareness to reduce morbidity and treatment costs and true ipilimumab success is dictated by both objective tumor responses and controlling severe side effects

    High-Fat Diet Induces Unexpected Fatal Uterine Infections in Mice with aP2 -Cre-mediated Deletion of Estrogen Receptor Alpha

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    Estrogen receptor alpha (ERα) is a major regulator of metabolic processes in obesity. In this study we aimed to define the relevance of adipose tissue ERα during high-fat diet (HFD)-induced obesity using female aP2-Cre−/+/ERαfl/fl mice (atERαKO). HFD did not affect body weight or glucose metabolism in atERαKO- compared to control mice. Surprisingly, HFD feeding markedly increased mortality in atERαKO mice associated with a destructive bacterial infection of the uterus driven by commensal microbes, an alteration likely explaining the absence of a metabolic phenotype in HFD-fed atERαKO mice. In order to identify a mechanism of the exaggerated uterine infection in HFD-fed atERαKO mice, a marked reduction of uterine M2-macrophages was detected, a cell type relevant for anti-microbial defence. In parallel, atERαKO mice exhibited elevated circulating estradiol (E2) acting on E2-responsive tissue/cells such as macrophages. Accompanying cell culture experiments showed that despite E2 co-administration stearic acid (C18:0), a fatty acid elevated in plasma from HFD-fed atERαKO mice, blocks M2-polarization, a process known to be enhanced by E2. In this study we demonstrate an unexpected phenotype in HFD-fed atERαKO involving severe uterine bacterial infections likely resulting from a previously unknown negative interference between dietary FAs and ERα- signaling during anti-microbial defence

    Simulation of FRET dyes allows quantitative comparison against experimental data

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    Fully understanding biomolecular function requires detailed insight into the systems’ structural dynamics. Powerful experimental techniques such as single molecule Förster Resonance Energy Transfer (FRET) provide access to such dynamic information yet have to be carefully interpreted. Molecular simulations can complement these experiments but typically face limits in accessing slow time scales and large or unstructured systems. Here, we introduce a coarse-grained simulation technique that tackles these challenges. While requiring only few parameters, we maintain full protein flexibility and include all heavy atoms of proteins, linkers, and dyes. We are able to sufficiently reduce computational demands to simulate large or heterogeneous structural dynamics and ensembles on slow time scales found in, e.g., protein folding. The simulations allow for calculating FRET efficiencies which quantitatively agree with experimentally determined values. By providing atomically resolved trajectories, this work supports the planning and microscopic interpretation of experiments. Overall, these results highlight how simulations and experiments can complement each other leading to new insights into biomolecular dynamics and function

    Safety and Efficacy of Itraconazole Compared to Amphotericin B as Empirical Antifungal Therapy for Neutropenic Fever in Patients with Haematological Malignancy

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    Safety, tolerability and efficacy of itraconazole and amphotericin B (AMB) were compared for empirical antifungal treatment of febrile neutropenic cancer patients. Patients and Methods: In an open, randomised study, 162 patients with at least 72 h of antimicrobial treatment received either intravenous followed by oral itraconazole suspension or intravenous AMB for a maximum of 28 days. Permanent discontinuation of study medication due to any adverse event was the primary safety parameter. Efficacy parameters included response and success rate for both treatment groups. Results: Significantly fewer itraconazole patients discontinued treatment due to any adverse event (22.2 vs. 56.8% AMB; p < 0.0001). The main reason for discontinuation was a rise in serum creatinine (1.2% itraconazole vs. 23.5% AMB). Renal toxicity was significantly higher and more drug-related adverse events occurred in the AMB group. Intention-to-treat (ITT) analysis showed favourable efficacy for itraconazole: response and success rate were both significantly higher than for AMB (61.7 vs. 42% and 70.4 vs. 49.3%, both p < 0.0001). Treatment failure was markedly reduced in itraconazole patients (25.9 vs. 43.2%), largely due to the better tolerability. Conclusions: Itraconazole was tolerated significantly better than conventional AMB and also showed advantages regarding efficacy. This study confirms the role of itraconazole as a useful and safe agent in empirical antifungal therapy of febrile neutropenic cancer patients.Hintergrund: Es wurden die Sicherheit, VertrĂ€glichkeit und Wirksamkeit von Itraconazol und Amphotericin B (AMB) in der antimykotischen Therapie der persistierend febrilen Neutropenie verglichen. Patienten und Methoden: In einer offenen, randomisierten Studie erhielten 162 Patienten mit mindestens 72-stĂŒndiger antibiotischer Therapie entweder Itraconazol (erst intravenös, dann oral) oder AMB (intravenös) fĂŒr maximal 28 Tage. PrimĂ€rer Sicherheitsparameter war die dauerhafte Unterbrechung der Studienmedikation aufgrund von Nebenwirkungen. Die Wirksamkeitsparameter umfassten die Ansprech- und Erfolgsrate fĂŒr beide Behandlungsgruppen. Ergebnisse: Signifikant weniger Itraconazol-Patienten brachen die Behandlung wegen Nebenwirkungen ab (22,2 vs. 56,8% AMB; p < 0,0001). Hauptursache fĂŒr StudienabbrĂŒche war der Anstieg des Serum-Kreatinin-Spiegels (1,2% Itraconazol vs. 23,5% AMB). Nephrotoxische und weitere Nebenwirkungen traten im AMB-Studienarm signifikant hĂ€ufiger auf. Intention-to-Treat (ITT)-Analysen zeigten eine bessere Wirksamkeit von Itraconazol: Ansprech- und Erfolgsrate waren signifikant höher als unter AMB (61,7 vs. 42% und 70,4 vs. 49,3%, beide p < 0,0001). Behandlungsversagen trat bei Itraconazol-Patienten merklich weniger auf (25,9 vs. 43,2%). Schlussfolgerungen: Die VertrĂ€glichkeit von Itraconazol war signifikant höher als beim herkömmlichen AMB. Itraconazol zeigte ebenfalls Vorteile in der Wirksamkeit. Diese Studie bestĂ€tigt die Rolle von Itraconazol als sinnvolles und sicheres Medikament in der empirischen antimykotischen Therapie von fiebrigen neutropenischen Tumorpatienten.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugĂ€nglich

    Light element abundances in carbon-enhanced metal-poor stars

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    We model the evolution of the abundances of light elements in carbon-enhanced metal-poor (CEMP) stars, under the assumption that such stars are formed by mass transfer in a binary system. We have modelled the accretion of material ejected by an asymptotic giant branch star on to the surface of a companion star. We then examine three different scenarios: one in which the material is mixed only by convective processes, one in which thermohaline mixing is present and a third in which both thermohaline mixing and gravitational settling are taken in to account. The results of these runs are compared to light element abundance measurements in CEMP stars (primarily CEMP-s stars, which are rich in ss-processes elements and likely to have formed by mass transfer from an AGB star), focusing on the elements Li, F, Na and Mg. None of the elements is able to provide a conclusive picture of the extent of mixing of accreted material. We confirm that lithium can only be preserved if little mixing takes place. The bulk of the sodium observations suggest that accreted material is effectively mixed but there are also several highly Na and Mg-rich objects that can only be explained if the accreted material is unmixed. We suggest that the available sodium data may hint that extra mixing is taking place on the giant branch, though we caution that the data is sparse.Comment: Accepted for publication in MNRAS. 9 figures, 1 tabl
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