86 research outputs found

    Assoziation organischer Bodensubstanz mit mineralischen OberflÀchen in einem ackerbaulich genutzten Oberboden mit unterschiedlicher Bodentextur

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    Die Menge und mikroskalige Verteilung mineralassoziierter organischer Bodensubstanz (engl. mineral-associated organic matter, MOM) hĂ€ngt von der VerfĂŒgbarkeit und ZugĂ€nglichkeit adsorptiver MineraloberflĂ€chen ab. In tonarmen Böden mit wenig MineraloberflĂ€che mĂŒsste der Bedeckungsgrad an organischer Substanz entsprechend höher sein als in tonreichen Böden bei gleicher MOM Konzentration. In dieser Arbeit wurde MOM im Oberboden (0-20 cm) einer ackerbaulich genutzten (Para-)Braunerde mit unterschiedlicher Bodentextur untersucht. Die beprobte FlĂ€che in Scheyern (Bayern, Deutschland) wurde einheitlich bewirtschaftet und mit gleichen Mengen organischen Materials versorgt. Der Texturgradient (6-37 % Partikel in der Tonfraktion) lĂ€sst sich wahrscheinlich auf unterschiedliche Lössanteile in den grobkörnigeren TertiĂ€rsedimenten zurĂŒckfĂŒhren. Um die MOM zu untersuchen, wurde aus der schweren Dichtefraktion >1,6 g cm‑3 die Feinschluff- (2‑6,3 ”m) und Tonfraktion (0,2‑2 ”m) gewonnen. Neben der Konzentration mineralassoziierten Kohlenstoffs wurde die chemische Zusammensetzung der MOM durch 13C-Festkörper-Kernresonanzspektroskopie bestimmt. In der Tonfraktion wurde durch Nano SekundĂ€rionen-Massenspektrometrie (NanoSIMS) die rĂ€umliche Verteilung der Ionen 16O‑, 12C‑ und 12C14N‑ bestimmt, welche mittels Bildbearbeitung als Indikator des rĂ€umlichen organischen Bedeckungsgrads herangezogen wurde. Röntgenbeugungsanalysen haben gezeigt, dass die mineralogische Zusammensetzung Ă€hnlich ist, wobei die Auswirkungen eines schwankenden Vermiculitgehalts noch durch Bestimmung der KationenaustauschkapazitĂ€t nĂ€her ĂŒberprĂŒft werden. Die Konzentration mineralassoziierten Kohlenstoffs in der Feinschluff und Tonfraktion war bei 6 % Tongehalt mit 80 mg g‑1 höher als bei 15 % Tongehalt mit 40 mg g‑1. In den Böden mit Tongehalt zwischen 15 und 30 % war die Konzentration mineralassoziierten Kohlenstoffs dagegen konstant bei etwa 40 mg g‑1. ZusĂ€tzlich zeigten die NanoSIMS-Messungen einen höheren organischen Bedeckungsgrad in den tonarmen Böden als in den tonreichen Böden. Unsere Daten besagen, dass in den untersuchten tonarmen Böden unter 15 % Tongehalt die MOM Konzentration als auch der Bedeckungsgrad höher ist je niedriger der Tongehalt. In den untersuchten tonreichen Böden ĂŒber 15 % Tongehalt war die MOM Konzentration und der organische Bedeckungsgrad konstant niedrig, was auf ausreichende VerfĂŒgbarkeit und ZugĂ€nglichkeit adsorptiver MineraloberflĂ€chen ab dieser Bodentextur schließen lĂ€sst

    Exploring the translational challenge for medical applications of ionising radiation and corresponding radiation protection research

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    This is the final version. Available on open access from BMC via the DOI in this recordAvailability of Data and Materials: The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.Background: Medical applications of ionising radiation and associated radiation protection research often encounter long delays and inconsistent implementation when translated into clinical practice. A coordinated effort is needed to analyse the research needs for innovation transfer in radiation-based high-quality healthcare across Europe which can inform the development of an innovation transfer framework tailored for equitable implementation of radiation research at scale. Methods: Between March and September 2021 a Delphi methodology was employed to gain consensus on key translational challenges from a range of professional stakeholders. A total of three Delphi rounds were conducted using a series of electronic surveys comprised of open-ended and closed-type questions. The surveys were disseminated via the EURAMED Rocc-n-Roll consortium network and prominent medical societies in the field. Approximately 350 professionals were invited to participate. Participants’ level of agreement with each generated statement was captured using a 6-point Likert scale. Consensus was defined as median ≄4 with ≄60% of responses in the upper tertile of the scale. Additionally, the stability of responses across rounds was assessed. Results: In the first Delphi round a multidisciplinary panel of 20 generated 127 unique statements. The second and third Delphi rounds recruited a broader sample of 130 individuals to rate the extent to which they agreed with each statement as a key translational challenge. A total of 60 consensus statements resulted from the iterative Delphi process of which 55 demonstrated good stability. Ten statements were identified as high priority challenges with ≄80% of statement ratings either ‘Agree’ or ‘Strongly Agree’. Conclusion: A lack of interoperability between systems, insufficient resources, unsatisfactory education and training, and the need for greater public awareness surrounding the benefits, risks, and applications of ionising radiation were identified as principal translational challenges. These findings will help to inform a tailored innovation transfer framework for medical radiation research.European Commissio

    Lifetime study in mice after acute low-dose ionizing radiation: a multifactorial study with special focus on cataract risk

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    Because of the increasing application of ionizing radiation in medicine, quantitative data on effects of low-dose radiation are needed to optimize radiation protection, particularly with respect to cataract development. Using mice as mammalian animal model, we applied a single dose of 0, 0.063, 0.125 and 0.5 Gy at 10 weeks of age, determined lens opacities for up to 2 years and compared it with overall survival, cytogenetic alterations and cancer development. The highest dose was significantly associated with increased body weight and reduced survival rate. Chromosomal aberrations in bone marrow cells showed a dose-dependent increase 12 months after irradiation. Pathological screening indicated a dose-dependent risk for several types of tumors. Scheimpflug imaging of the lens revealed a significant dose-dependent effect of 1% of lens opacity. Comparison of different biological end points demonstrated long-term effects of low-dose irradiation for several biological end points

    Effect of Chronic Kidney Diseases on Mortality among Digoxin Users Treated for Non-Valvular Atrial Fibrillation: A Nationwide Register-Based Retrospective Cohort Study.

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    PURPOSE: This study investigated the impact of chronic kidney disease on all-causes and cardiovascular mortality in patients with atrial fibrillation treated with digoxin. METHODS: All patients with non-valvular atrial fibrillation and/or atrial flutter as hospitalization diagnosis from January 1, 1997 to December 31, 2012 were identified in Danish nationwide administrative registries. Cox proportional hazard model was used to compare the adjusted risk of all-causes and cardiovascular mortality among patients with and without chronic kidney disease and among patients with different chronic kidney disease stages within 180 days and 2 years from the first digoxin prescription. RESULTS: We identified 37,981 patients receiving digoxin; 1884 patients had the diagnosis of chronic kidney disease. Cox regression analysis showed no statistically significant differences in all-causes (Hazard Ratio, HR 0.89; 95% confident interval, CI 0.78-1.03) and cardiovascular mortality (HR 0.88; 95%CI 0.74-1.05) among patients with and without chronic kidney disease within 180 days of follow-up period. No statistically significant differences was found using a 2 years follow-up period neither for all causes mortality (HR 0.90; 95%CI 0.79-1.03), nor for cardiovascular mortality (HR 0.87; 95%CI 0.74-1.02). No statistically significant differences was found comparing patients with and without estimated Glomerular Filtration Rate <30ml/min/1.73m2 and patients with different stages of chronic kidney disease, for all-causes and cardiovascular mortality within 180 days and 2 years from the first digoxin prescription. CONCLUSIONS: This study suggest no direct effect of chronic kidney disease and chronic kidney disease stages on all-causes and cardiovascular mortality within both 180 days and 2 years from the first digoxin prescription in patients treatment-naĂŻve with digoxin for non-valvular atrial fibrillation

    Forward modeling of collective Thomson scattering for Wendelstein 7-X plasmas: Electrostatic approximation

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    In this paper, we present a method for numerical computation of collective Thomson scattering (CTS). We developed a forward model, eCTS, in the electrostatic approximation and benchmarked it against a full electromagnetic model. Differences between the electrostatic and the electromagnetic models are discussed. The sensitivity of the results to the ion temperature and the plasma composition is demonstrated. We integrated the model into the Bayesian data analysis framework Minerva and used it for the analysis of noisy synthetic data sets produced by a full electromagnetic model. It is shown that eCTS can be used for the inference of the bulk ion temperature. The model has been used to infer the bulk ion temperature from the first CTS measurements on Wendelstein 7-X

    Towards a new image processing system at Wendelstein 7-X: From spatial calibration to characterization of thermal events

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    Wendelstein 7-X (W7-X) is the most advanced fusion experiment in the stellarator line and is aimed at proving that the stellarator concept is suitable for a fusion reactor. One of the most important issues for fusion reactors is the monitoring of plasma facing components when exposed to very high heat loads, through the use of visible and infrared (IR) cameras. In this paper, a new image processing system for the analysis of the strike lines on the inboard limiters from the first W7-X experimental campaign is presented. This system builds a model of the IR cameras through the use of spatial calibration techniques, helping to characterize the strike lines by using the information given by real spatial coordinates of each pixel. The characterization of the strike lines is made in terms of position, size, and shape, after projecting the camera image in a 2D grid which tries to preserve the curvilinear surface distances between points. The description of the strike-line shape is made by means of the Fourier Descriptors

    Strategic research agenda for biomedical imaging

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    This Strategic Research Agenda identifies current challenges and needs in healthcare, illustrates how biomedical imaging and derived data can help to address these, and aims to stimulate dedicated research funding efforts. Medicine is currently moving towards a more tailored, patient-centric approach by providing personalised solutions for the individual patient. Innovation in biomedical imaging plays a key role in this process as it addresses the current needs for individualised prevention, treatment, therapy response monitoring, and image-guided surgery. The use of non-invasive biomarkers facilitates better therapy prediction and monitoring, leading to improved patient outcomes. Innovative diagnostic imaging technologies provide information about disease characteristics which, coupled with biological, genetic and -omics data, will contribute to an individualised diagnosis and therapy approach. In the emerging field of theranostics, imaging tools together with therapeutic agents enable the selection of best treatments and allow tailored therapeutic interventions. For prenatal monitoring, the use of innovative imaging technologies can ensure an early detection of malfunctions or disease. The application of biomedical imaging for diagnosis and management of lifestyle-induced diseases will help to avoid disease development through lifestyle changes. Artificial intelligence and machine learning in imaging will facilitate the improvement of image interpretation and lead to better disease prediction and therapy planning. As biomedical imaging technologies and analysis of existing imaging data provide solutions to current challenges and needs in healthcare, appropriate funding for dedicated research is needed to implement the innovative approaches for the wellbeing of citizens and patients

    SIMULATING A REGULARLY SAMPLED BUS LOCATION SYSTEM

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    Between 1967 and 1997, transit agencies in 20 cities installed automatic vehicle location (AVL) systems to improve safety, efficiency, and quality of service. The bus AVL system typically provides a means of tracking individual buses for fleet management. More recently, the AVL data have also been used to develop algorithms to predict bus arrival time, estimate link travel time, and detect incidents. Other traffic management and control applications are also being explored. Therefore, the availability of a simulation capable of mimicking a bus location system that reports vehicle location at regular, prespecified intervals is becoming increasingly important. CORSIM, an integrated freeway and surface street traffic simulation model, also simulates buses on prespecified routes and stations for given dwell time distributions and frequency of service. However, very little has been reported about CORSIM\u27s bus simulation module. CORSIM\u27s bus route simulation module and its drawbacks are examined, and the results of an effort to compare data collected from the Denver Regional Transportation District bus AVL system and the microsimulator for a test network are presented. Bus location data from the field and the simulation were collected at regular intervals under both recurring congestion and nonrecurring congestion conditions. Linear referencing in a geographic information system was used to extract bus location data for the test network from the AVL system, and external programs were written to collect the same data from the microsimulator. Based on the bus location data, space mean speeds were estimated and compared to evaluate the performance of the model. The results are encouraging. However, several obstacles remain and they are discussed in detail

    Only therapeutic ICOS:ICOSL blockade alleviates acute graft versus host disease.

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    Inducible co-stimulator (ICOS) interaction with its ligand (ICOSL) is involved in several T cell effector functions. While blockade of ICOS:ICOSL interaction in chronic graft versus host disease (GVHD) seems beneficial, results for acute GVHD remain controversial. To further elucidate its role in acute GVHD, C57BL/6 mice were reconstituted with allogeneic spleen cells in the absence or presence of ICOSL-blocking mAb. Mice reconstituted with allogeneic spleen cells experienced severe GVHD and died untreated within 6-9 days after transplantation. Mice treated with an anti-ICOSL mAb starting from day 3 after transplantation gained weight again and survived for at least additional 12 days, although the treatment was already stopped at day 11 after transplantation. In contrast, the anti-ICOSL treatment starting from day 0 did not prevent GVHD. The difference between therapeutic (day 3) and prophylactic (day 0) anti-ICOSL treatment was independent of CD25+CD4+ regulatory T cells since their depletion did not abrogate the therapeutic effect of ICOSL blockade. Microarray analysis revealed IFN-gamma and chemokine up-regulation in spleen cells of prophylactically treated mice, emphasizing kinetic dependence of acute GVHD modulation via blockade of ICOS:ICOSL interaction
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