1,792 research outputs found

    Salinity-independent dissipation of antibiotics from flooded tropical soil: a microcosm study

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    River deltas are frequently facing salinity intrusion, thus challenging agricultural production in these areas. One adaption strategy to increasing salinity is shrimp production, which however, heavily relies on antibiotic usage. This study was performed to evaluate the effect of increasing salinity on the dissipation rates of antibiotics in tropical flooded soil systems. For this purpose, paddy top soil from a coastal Vietnamese delta was spiked with selected frequently used antibiotics (sulfadiazine, sulfamethazine, sulfamethoxazole, trimethoprim) and incubated with flood water of different salt concentrations (0, 10, 20 g L−1). Antibiotic concentrations were monitored in water and soil phases over a period of 112 days using liquid chromatography and tandem mass spectrometry. We found that sulfamethazine was the most persistent antibiotic in the flooded soil system (DT50 = 77 days), followed by sulfadiazine (DT50 = 53 days), trimethoprim (DT50 = 3 days) and sulfamethoxazole (DT50 = 1 days). With the exception of sulfamethoxazole, the apparent distribution coefficient increased significantly (p < 0.05) for all antibiotics in course of the incubation, which indicates an accumulation of antibiotics in soil. On a whole system basis, including soil and water into the assessment, there was no overall salinity effect on the dissipation rates of antibiotics, suggesting that common e-fate models remain valid under varying salinity

    The Economics of Desertification, Land Degradation, and Drought; Toward an Integrated Global Assessment

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    Land degradation has not been comprehensively addressed at the global level or in developing countries. A suitable economic framework that could guide investments and institutional action is lacking. This study aims to overcome this deficiency and to provide a framework for a global assessment based on a consideration of the costs of action versus inaction regarding desertification, land degradation, and drought (DLDD). Most of the studies on the costs of land degradation (mainly limited to soil erosion) give cost estimates of less than 1 percent up to about 10 percent of the agricultural gross domestic product (GDP) for various countries worldwide. But the indirect costs of DLDD on the economy (national income), as well as their socioeconomic consequences (particularly poverty impacts), must be accounted for, too. Despite the numerous challenges, a global assessment of the costs of action and inaction against DLDD is possible, urgent, and necessary. This study provides a framework for such a global assessment and provides insights from some related country studies.Agricultural Finance, Crop Production/Industries, Environmental Economics and Policy, Land Economics/Use, Resource /Energy Economics and Policy,

    Lasting Effects of a Graduate Pedagogy Course on the Development of Teacher-Scholars

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    While graduate pedagogy courses may result in specific teaching behaviors in the short term, little is known whether these scholarly teaching behaviors and attitudes endure over time. Multiple evidenced-based assessments of pedagogy courses which continue well past the completion of the course can demonstrate the ongoing development of students’ perceptions of teaching and learning and students’ progression as teacher-scholars. This poster summarizes an investigation exploring the lasting effects of a graduate pedagogy course entitled MSCI M620: Pedagogical Methods in Health Sciences. This course has been offered for two semesters and a total of sixteen graduate students from a variety of science-related disciplines enrolled in the course. We examined whether the course caused students to: 1) Develop more complex and refined attitudes regarding student learning; 2) Evaluate their current teaching methods and explore alternative teaching strategies; 3) Assess their teaching effectiveness; 4) Plan to be involved in a public teaching resource network; and 5) Develop lasting attitudes about scholarly teaching

    Timelines of Tension: Trajectories of Protected-Area Creation in the Austrian Alps

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    The establishment of protected areas is often preceded by tensions and intense discussions between stakeholders of differing interests. Governmental bodies, environmental conservation groups and local actors, such as farmers or locals involved in tourism, are either in favour of or in opposition to the designation of protected areas in their home regions. Using two protected areas in the Eastern Austrian Alps as cases in point, the present study combines the methods of oral history and archival research to trace these timelines of tension and to identify the actors involved and the issues debated on the way to designation. Our results reveal the complex nature of both cases shaped by a variety of actors from the public, non-profit (or voluntary) and private sectors. After up to 30 years of discussions, both protected areas now seem to be accepted by large parts of the local population and are even well-integrated in the regional agrarian and touristic setting. To shorten these “timelines of tension” in future conservation projects, communication measures and strategies could clearly be improved and past experiences of protected area designations made available to present policy makers of the Alpine region. In this way, new protected areas could be established without undue tensions and pave the way for sustainable development in sensitive environments of the European Alps

    Broad AOX expression in a genetically tractable mouse model does not disturb normal physiology

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    Plants and many lower organisms, but not mammals, express alternative oxidases (AOXs) that branch the mitochondrial respiratory chain, transferring electrons directly from ubiquinol to oxygen without proton pumping. Thus, they maintain electron flow under conditions when the classical respiratory chain is impaired, limiting excess production of oxygen radicals and supporting redox and metabolic homeostasis. AOX from Ciona intestinalis has been used to study and mitigate mitochondrial impairments in mammalian cell lines, Drosophila disease models and, most recently, in the mouse, where multiple lentivector-AOX transgenes conferred substantial expression in specific tissues. Here, we describe a genetically tractable mouse model in which Ciona AOX has been targeted to the Rosa26 locus for ubiquitous expression. The AOX(Rosa26) mouse exhibited only subtle phenotypic effects on respiratory complex formation, oxygen consumption or the global metabolome, and showed an essentially normal physiology. AOX conferred robust resistance to inhibitors of the respiratory chain in organello; moreover, animals exposed to a systemically applied LD50 dose of cyanide did not succumb. The AOX(Rosa26) mouse is a useful tool to investigate respiratory control mechanisms and to decipher mitochondrial disease aetiology in vivo.Peer reviewe

    Six-month outcomes after individualized nutritional support during the hospital stay in medical patients at nutritional risk: Secondary analysis of a prospective randomized trial.

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    BACKGROUND Among medical inpatients at risk of malnutrition, the use of individualized nutritional support during the hospital stay was found to reduce complications and improve mortality at short-term. We evaluated clinical outcomes at 6-months follow-up. METHODS We randomly assigned 2028 patients to receive protocol-guided individualized nutritional support to reach protein and energy goals (intervention group) or hospital food as usual (control group) during the hospital stay. The intervention was discontinued at hospital discharge and further nutritional support was based on the discretion of the treating team. We had complete follow-up information of 1995 patients (98%), which were included in the final analysis. The primary endpoint was all-cause mortality at 6-months. Prespecified secondary end points included non-elective hospital readmissions, functional outcome and quality of life. RESULTS At 6-month, 231 of 994 (23.2%) intervention group patients had died compared to 246 of 999 (24.6%) control group patients, resulting in a hazard ratio for death of 0.90 (95%CI 0.76 to 1.08, p = 0.277). Compared to control patients, intervention group patients had similar rates of hospital readmission (27.3% vs. 27.6%, HR 1.00 (95%CI 0.84 to 1.18), p = 0.974), falls (11.2% vs. 10.9%, HR 0.96 (95%CI 0.72 to 1.27), p = 0.773) and similar quality of life and activities of daily living scores. INTERPRETATION While individualized nutritional support during the hospital stay significantly reduced short-term mortality, there was no legacy effect on longer term outcomes. Future trials should investigate whether continuation of nutritional support after hospital discharge reduces the high malnutrition-associated mortality rates in this vulnerable patient population. TRIAL REGISTRATION ClinicalTrials.gov number, NCT02517476
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