483 research outputs found

    Assessment of future agricultural conditions in southwestern Africa using fuzzy logic and high-resolution climate model scenarios

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    Climate change is expected to have a major impact on the arid savanna regions of southwestern Africa, such as the Okavango Basin. Precipitation is a major constraint for agriculture in countries like Namibia and Botswana and assessments of future crop growth conditions are in high demand. This GIS-based approach uses reanalysis data and climate model output for two scenarios and compares them to the precipitation requirements of the five most important crops grown in the region: maize, pearl millet, sorghum, cassava and cow pea. It also takes into account the dominant soil types, as plant growth is also limited by nutrient-poor soils with unfavorable physical and chemical properties. The two factors are then combined using a fuzzy logic algorithm. The assessment visualizes the expected shifts in suitable zones and identifies areas where farming without irrigation may experience a decline in yields or may even no longer be possible at the end of the 21st century. The results show that pearl millet is the most suitable crop in all scenarios while especially the cultivation of maize, sorghum and cow pea may be affected by a possible reduction of precipitation under the high-emission scenario

    Realistic FD modeling of the tunnel environment for seismic tomography

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    To improve the safety both of the tunnel constructions and buildings at the surface, seismic tomography methods can be used to detect possible safety threads behind the tunnel wall (e.g. cavities, water bearing zones, fractures). Basis for such a tomography is a profound understanding of the seismic wave propagation in the complex surrounding of a tunnel which can be gained from seismic modeling We, therefore, created a realistic tunnel model that accounts for typical features encountered during tunnel construction, e.g. heterogeneous host rock, excavation damaged zone (EDZ) and topography of the tunnel wall. This model is used for the 3-D elastic wave field simulations. Data from multiple shot positions will be later on used for a seismic tomography, either by standard travel time tomography or full waveform tomography. Main objective is the accurate seismic modeling using optimal discretization parameters and an implicit free surface boundary with topography

    Selective synthesis of primary amines by kinetic-based optimization of the ruthenium-Xantphos catalysed amination of alcohols with ammonia

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    The selective synthesis of primary amines directly from several alcohols and ammonia using a homogeneous catalyst based on HRuCl(CO)(PPh3)3 and Xantphos is presented. The key to success was the detailed understanding of all mutually influencing parameters such as temperature, ammonia excess, and substrate concentration. These studies were supported by the determination of the kinetics, which allowed the reaction order to be calculated as 0.7. Furthermore, the kinetic model derived from the mechanism was confirmed. After measuring reaction profiles for all influencing parameters, optimized conditions were obtained, which finally allowed the amination of aliphatic, cyclic, as well as primary and secondary alcohols with selectivities to the desired primary amine exceeding 90 % at quantitative alcohol conversion with only minimal formation of the undesired secondary amines. Furthermore, the catalytic activity of the commercially available and robust Xantphos system was drastically improved, corresponding to a turnover frequency (TOF)>60 h−1 after 30 minutes and a turnover number (TON) of 120

    Balancing control and autonomy in master surgery scheduling: benefits of ICU quotas for recovery units

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    When scheduling surgeries in the operating theater, not only the resources within the operating theater have to be considered but also those in downstream units, e.g., the intensive care unit and regular bed wards of each medical specialty. We present an extension to the master surgery schedule, where the capacity for surgeries on ICU patients is controlled by introducing downstream-dependent block types – one for both ICU and ward patients and one where surgeries on ICU patients must not be performed. The goal is to provide better control over post-surgery patient flows through the hospital while preserving each medical specialty’s autonomy over its operational surgery scheduling. We propose a mixed-integer program to determine the allocation of the new block types within either a given or a new master surgery schedule to minimize the maximum workload in downstream units. Using a simulation model supported by seven years of data from the University Hospital Augsburg, we show that the maximum workload in the intensive care unit can be reduced by up to 11.22% with our approach while maintaining the existing master surgery schedule. We also show that our approach can achieve up to 79.85% of the maximum workload reduction in the intensive care unit that would result from a fully centralized approach. We analyze various hospital setting instances to show the generalizability of our results. Furthermore, we provide insights and data analysis from the implementation of a quota system at the University Hospital Augsburg. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10729-021-09588-8

    Process Stabilization at welding Copper by Laser Power Modulation

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    AbstractDue to their material properties such as high electrical and thermal conductivity, copper materials are more and more demanded for industrial applications. The same material properties make laser welding of copper a challenging task. Laser welds often suffer from defective weld seams with ejections, pores and a large fluctuation in the penetration depth. In this paper the influence of laser power modulation during copper welding on weld imperfections is discussed. It is shown that a sinusoidal power modulation leads to a strong reduction of melt ejections and also to an increase in penetration depth

    Future agricultural conditions in the Nepal Himalaya - A fuzzy logic approach using high resolution climate scenarios

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    Until the end of the 21st century, ongoing climate change is expected to trigger major changes in site conditions and vertical species distributions in high mountain regions such as the Himalaya. Altitudinal ranges of species used as staple crops in Himalayan agriculture and currently suitable cultivation areas will be affected as well. Changing climatic variables such as temperature and precipitation will modify agricultural land-use options, and assessments of future crop growth conditions are in high demand. This GIS-based approach utilizes high resolution climate data of the present and two future scenarios and relates them to bioclimatic requirements of the five most important crops grown in Nepal: rice, maize, wheat, finger millet and potato. It takes into account soil pH as a basic constraint for the individual crop. The three factors  temperature, precipitation,and soil pH are then combined using a fuzzy logic algorithm. The assessment visualizes the expected shifts in suitable cultivation zones for the individual crops. The results show that wheat is likely to experience the most severe loss of crop suitability until the end of the 21st century, while the cultivation of rice is likely to benefit

    MOSGA: Modular Open-Source Genome Annotator

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    The generation of high-quality assemblies, even for large eukaryotic genomes, has become a routine task for many biologists thanks to recent advances in sequencing technologies. However, the annotation of these assemblies - a crucial step towards unlocking the biology of the organism of interest - has remained a complex challenge that often requires advanced bioinformatics expertise. Here we present MOSGA, a genome annotation framework for eukaryotic genomes with a user-friendly web-interface that generates and integrates annotations from various tools. The aggregated results can be analyzed with a fully integrated genome browser and are provided in a format ready for submission to NCBI. MOSGA is built on a portable, customizable, and easily extendible Snakemake backend, and thus, can be tailored to a wide range of users and projects. We provide MOSGA as a publicly free available web service at https://mosga.mathematik.uni-marburg.de and as a docker container at registry.gitlab.com/mosga/mosga:latest. Source code can be found at https://gitlab.com/mosga/mosg

    Income-, education- and gender-related inequalities in out-of-pocket health-care payments for 65+ patients - a systematic review

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    BACKGROUND: In all OECD countries, there is a trend to increasing patients' copayments in order to balance rising overall health-care costs. This systematic review focuses on inequalities concerning the amount of out-of-pocket payments (OOPP) associated with income, education or gender in the Elderly aged 65+. METHODS: Based on an online search (PubMed), 29 studies providing information on OOPP of 65+ beneficiaries in relation to income, education and gender were reviewed. RESULTS: Low-income individuals pay the highest OOPP in relation to their earnings. Prescription drugs account for the biggest share. A lower educational level is associated with higher OOPP for prescription drugs and a higher probability of insufficient insurance protection. Generally, women face higher OOPP due to their lower income and lower labour participation rate, as well as less employer-sponsored health-care. CONCLUSIONS: While most studies found educational and gender inequalities to be associated with income, there might also be effects induced solely by education; for example, an unhealthy lifestyle leading to higher payments for lower-educated people, or exclusively gender-induced effects, like sex-specific illnesses. Based on the considered studies, an explanation for inequalities in OOPP by these factors remains ambiguous
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