7,856 research outputs found

    Testing the Suitability of Zerovalent Iron Materials for Reactive Walls

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    Zerovalent iron (ZVI) has been proposed as reactive material in permeable in situ walls for contaminated groundwater. An economically feasible ZVI-based reactive wall requires cheap but efficient iron materials. From an uranium treatability study and results of iron dissolution in 0.002 M EDTA by five selected ZVI materials, it is shown that current research and field implementation is not based on a rational selection of application-specific iron metal sources. An experimental procedure is proposed which could enable a better material characterization. This procedure consists of mixing ZVI materials and reactive additives, including contaminant releasing materials (CRMs), in long-term batch experiments and characterizing the contaminant concentration over the time.Keywords: iron, redox reactions, uranium water, treatmentresearc

    Arbeitskreis Empirische Bildungsforschung in der Mathematikdidaktik

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    Rate of comorbidities in giant cell arteritis : A population-based study

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    Objective. To compare the rate of occurrence of comorbidities, including severe infections, in a population-based cohort of patients with biopsy-proven giant cell arteritis (GCA) with a reference population in Southern Sweden. Methods. The study included a population-based cohort of biopsy-proven GCA cases diagnosed between 1998 and 2010 from the Skane region in Southern Sweden (population: 1.2 million). For each patient, 4 reference subjects were identified from the general population and matched for age, sex, area of residence, and date of diagnosis of GCA. Using the Skane Healthcare Register, comorbidities and severe infections (requiring hospitalization) diagnosed after GCA onset were identified. The rate of the first occurrence of each comorbidity was the result of dividing the number of subjects with a given comorbidity by the person-years of followup. The rate ratio (RR; GCA:reference population) was also calculated. Results. There were 768 patients (571 women) with GCA and 3066 reference persons included in the study. The RR were significantly elevated for osteoporosis (2.81, 95% CI 2.33-3.37), followed by venous thromboembolic diseases (2.36, 95% CI 1.61-3.40), severe infections (1.85, 95% CI 1.57-2.18), thyroid diseases (1.55, 95% CI 1.25-1.91), cerebrovascular accidents (1.40, 95% CI 1.12-1.74), and diabetes mellitus (1.29, 95% CI 1.05-1.56). The RR for ischemic heart disease was elevated, but did not reach statistical significance (1.20, 95% CI 1.00-1.44). Conclusion. Patients with GCA have higher rates of selected comorbidities, including severe infections, compared with a reference population. Several of these comorbidities may be related to treatment with glucocorticosteroids, emphasizing the unmet need to find alternative treatments for GCA

    Anaerobic carboxydotrophy in sulfur-respiring haloarchaea from hypersaline lakes

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    Anaerobic carboxydotrophy is a widespread catabolic trait in bacteria, with two dominant pathways: hydrogenogenic and acetogenic. The marginal mode by direct oxidation to CO2 using an external e-acceptor has only a few examples. Use of sulfidic sediments from two types of hypersaline lakes in anaerobic enrichments with CO as an e-donor and elemental sulfur as an e-acceptor led to isolation of two pure cultures of anaerobic carboxydotrophs belonging to two genera of sulfur-reducing haloarchaea: Halanaeroarchaeum sp. HSR-CO from salt lakes and Halalkaliarchaeum sp. AArc-CO from soda lakes. Anaerobic growth of extremely halophilic archaea with CO was obligatory depended on the presence of elemental sulfur as the electron acceptor and yeast extract as the carbon source. CO served as a direct electron donor and H2 was not generated from CO when cells were incubated with or without sulfur. The genomes of the isolates encode a catalytic Ni,Fe-CODH subunit CooS (distantly related to bacterial homologs) and its Ni-incorporating chaperone CooC (related to methanogenic homologs) within a single genomic locus. Similar loci were also present in a genome of the type species of Halalkaliarchaeum closely related to AArc-CO, and the ability for anaerobic sulfur-dependent carboxydotrophy was confirmed for three different strains of this genus. Moreover, similar proteins are encoded in three of the four genomes of recently described carbohydrate-utilizing sulfur-reducing haloarchaea belonging to the genus Halapricum and in two yet undescribed haloarchaeal species. Overall, this work demonstrated for the first time the potential for anaerobic sulfur-dependent carboxydotrophy in extremely halophilic archaea.Accepted Author ManuscriptBT/Environmental Biotechnolog

    Erklärvideos: Chancen und Risiken Zwischen fachlicher Korrektheit und didaktischen Zielen

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    Der aktuelle Hype um Erklärvideos sollte nicht verdecken, dass ein erfolgreicher Einsatz auf soliden fachdidaktischen und fachlichen Prinzipien ruhen sollte. Der Beitrag diskutiert einige dazu nützliche Grundlagen und illustriert diese an ausgewählten Beispielen

    Evaluation of bicinchoninic acid as a ligand for copper(I)-catalyzed azide-alkyne bioconjugations

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    Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The Cu(I)-catalyzed cycloaddition of terminal azides and alkynes (click chemistry) represents a highly specific reaction for the functionalization of biomolecules with chemical moieties such as dyes or polymer matrices. In this study we evaluate the use of bicinchoninic acid (BCA) as a ligand for Cu(I) under physiological reaction conditions. We demonstrate that the BCA–Cu(I)-complex represents an efficient catalyst for the conjugation of fluorophores or biotin to alkyne- or azide-functionalized proteins resulting in increased or at least equal reaction yields compared to commonly used catalysts like Cu(I) in complex with TBTA (tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine) or BPAA (bathophenanthroline disulfonic acid). The stabilization of Cu(I) with BCA represents a new strategy for achieving highly efficient bioconjugation reactions under physiological conditions in many application fields.EC/FP7/259043/EU/Computing Biomaterials/COMPBIOMATDFG, EXC 294, BIOSS Zentrum für Biologische Signalstudien - von der Analyse zur SyntheseDFG, GSC 4, Spemann Graduiertenschule für Biologie und Medizin (SGBM

    GPrioSwap : Towards a Swapping Policy for GPUs

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    Over the last few years, Graphics Processing Units (GPUs) have become popular in computing, and have found their way into a number of cloud platforms. However, integrating a GPU into a cloud environment requires the cloud provider to efficiently virtualize the GPU. While several research projects have addressed this challenge in the past, few of these projects attempt to properly enable sharing of GPU memory between multiple clients: To date, GPUswap is the only project that enables sharing of GPU memory without inducing unnecessary application overhead, while maintaining both fairness and high utilization of GPU memory. However, GPUswap includes only a rudimentary swapping policy, and therefore induces a rather large application overhead. In this paper, we work towards a practicable swapping policy for GPUs. To that end, we analyze the behavior of various GPU applications to determine their memory access patterns. Based on our insights about these patterns, we derive a swapping policy that includes a developer-assigned priority for each GPU buffer in its swapping decisions. Experiments with our prototype implementation show that a swapping policy based on buffer priorities can significantly reduce the swapping overhead

    Effects of nintedanib in patients with limited cutaneous systemic sclerosis and interstitial lung disease

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    OBJECTIVES: To investigate the course of interstitial lung disease (ILD) and the effects of nintedanib in patients with limited cutaneous systemic sclerosis (lcSSc). METHODS: In the SENSCIS trial, patients with SSc-ILD were randomised to receive nintedanib or placebo. Patients who completed the SENSCIS trial were eligible to enter SENSCIS-ON, in which all patients received open-label nintedanib. RESULTS: Among 277 patients with lcSSc treated in the SENSCIS trial, the rate (SE) of decline in FVC (mL/year) over 52 weeks was -74.5 (19.2) in the placebo group and -49.1 (19.8) in the nintedanib group (difference: 25.3 [95% CI -28.9, 79.6]). Among 249 patients with data at week 52, mean (SE) changes in FVC at week 52 were -86.4 (21.1) mL in the placebo group and -39.1 (22.2) mL in the nintedanib group. Among 183 patients with lcSSc who participated in SENSCIS-ON and had data at week 52, mean (SE) changes in FVC from baseline to week 52 of SENSCIS-ON were -41.5 (24.0) mL in patients who took placebo in the SENSCIS trial and initiated nintedanib in SENSCIS-ON and -45.1 (19.1) mL in patients who took nintedanib in the SENSCIS trial and continued it in SENSCIS-ON. CONCLUSION: Patients with lcSSc may develop progressive fibrosing ILD. By targeting pulmonary fibrosis, nintedanib slows decline in lung function in patients with lcSSc and ILD. TRIAL REGISTRATION: ClinicalTrials.gov (https://www.clinicaltrials.gov), NCT02597933 and NCT03313180

    Measurements of the mean structure, temperature, and circulation of the MLT

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    The mean state of the MLT (mesosphere – lower thermosphere) is key in the exchange of energy, momentum, and trace species between the middle and upper atmosphere. Knowledge of the mean state wind and temperature is endangered by an upcoming gap in measurements. Needed actions include continued operation of existing space-borne instruments and rapid development of replacement options
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