50 research outputs found

    Magnesium based materials for hydrogen based energy storage: Past, present and future

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    Magnesium hydride owns the largest share of publications on solid materials for hydrogen storage. The “Magnesium group” of international experts contributing to IEA Task 32 “Hydrogen Based Energy Storage” recently published two review papers presenting the activities of the group focused on magnesium hydride based materials and on Mg based compounds for hydrogen and energy storage. This review article not only overviews the latest activities on both fundamental aspects of Mg-based hydrides and their applications, but also presents a historic overview on the topic and outlines projected future developments. Particular attention is paid to the theoretical and experimental studies of Mg-H system at extreme pressures, kinetics and thermodynamics of the systems based on MgH2, nanostructuring, new Mg-based compounds and novel composites, and catalysis in the Mg based H storage systems. Finally, thermal energy storage and upscaled H storage systems accommodating MgH2 are presented

    A global outlook to the interruption of education due to COVID-19 Pandemic: Navigating in a time of uncertainty and crisis

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    Uncertain times require prompt reflexes to survive and this study is a collaborative reflex to better understand uncertainty and navigate through it. The Coronavirus (Covid-19) pandemic hit hard and interrupted many dimensions of our lives, particularly education. As a response to interruption of education due to the Covid-19 pandemic, this study is a collaborative reaction that narrates the overall view, reflections from the K12 and higher educational landscape, lessons learned and suggestions from a total of 31 countries across the world with a representation of 62.7% of the whole world population. In addition to the value of each case by country, the synthesis of this research suggests that the current practices can be defined as emergency remote education and this practice is different from planned practices such as distance education, online learning or other derivations. Above all, this study points out how social injustice, inequity and the digital divide have been exacerbated during the pandemic and need unique and targeted measures if they are to be addressed. While there are support communities and mechanisms, parents are overburdened between regular daily/professional duties and emerging educational roles, and all parties are experiencing trauma, psychological pressure and anxiety to various degrees, which necessitates a pedagogy of care, affection and empathy. In terms of educational processes, the interruption of education signifies the importance of openness in education and highlights issues that should be taken into consideration such as using alternative assessment and evaluation methods as well as concerns about surveillance, ethics, and data privacy resulting from nearly exclusive dependency on online solutions

    Biological detoxification of the mycotoxin deoxynivalenol and its use in genetically engineered crops and feed additives

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    Deoxynivalenol (DON) is the major mycotoxin produced by Fusarium fungi in grains. Food and feed contaminated with DON pose a health risk to humans and livestock. The risk can be reduced by enzymatic detoxification. Complete mineralization of DON by microbial cultures has rarely been observed and the activities turned out to be unstable. The detoxification of DON by reactions targeting its epoxide group or hydroxyl on carbon 3 is more feasible. Microbial strains that de-epoxidize DON under anaerobic conditions have been isolated from animal digestive system. Feed additives claimed to de-epoxidize trichothecenes enzymatically are on the market but their efficacy has been disputed. A new detoxification pathway leading to 3-oxo-DON and 3-epi-DON was discovered in taxonomically unrelated soil bacteria from three continents; the enzymes involved remain to be identified. Arabidopsis, tobacco, wheat, barley, and rice were engineered to acetylate DON on carbon 3. In wheat expressing DON acetylation activity, the increase in resistance against Fusarium head blight was only moderate. The Tri101 gene from Fusarium sporotrichioides was used; Fusarium graminearum enzyme which possesses higher activity towards DON would presumably be a better choice. Glycosylation of trichothecenes occurs in plants, contributing to the resistance of wheat to F. graminearum infection. Marker-assisted selection based on the trichothecene-3-O-glucosyltransferase gene can be used in breeding for resistance. Fungal acetyltransferases and plant glucosyltransferases targeting carbon 3 of trichothecenes remain promising candidates for engineering resistance against Fusarium head blight. Bacterial enzymes catalyzing oxidation, epimerization, and less likely de-epoxidation of DON may extend this list in future

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

    Materials for hydrogen-based energy storage - past, recent progress and future outlook

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    Globally, the accelerating use of renewable energy sources, enabled by increased efficiencies and reduced costs, and driven by the need to mitigate the effects of climate change, has significantly increased research in the areas of renewable energy production, storage, distribution and end-use. Central to this discussion is the use of hydrogen, as a clean, efficient energy vector for energy storage. This review, by experts of Task 32, “Hydrogen-based Energy Storage” of the International Energy Agency, Hydrogen TCP, reports on the development over the last 6 years of hydrogen storage materials, methods and techniques, including electrochemical and thermal storage systems. An overview is given on the background to the various methods, the current state of development and the future prospects. The following areas are covered; porous materials, liquid hydrogen carriers, complex hydrides, intermetallic hydrides, electrochemical storage of energy, thermal energy storage, hydrogen energy systems and an outlook is presented for future prospects and research on hydrogen-based energy storage

    Toxin-producing fungi on feed grains and application of yeasts for their detoxification

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    The research deals with the contamination of feeding crops with fungi, producing mycotoxins and use of selected yeasts for detoxification. The thin-layer chromatography and ELISA methods were applied for the analysis of fungal secondary metabolites. The results showed a high rate of the grain contamination with fungi, mainly from genera Penicillium, Fusarium, Aspergillus and Alternaria. Some of the fungal strains produced 6-9 toxic compounds. The novelty of the study was the application of the yeast strains in detoxification of aflatoxins, zearalenon and deoxynivalenol in feed

    Non-Ischemic Heart Preservation versus Static Cold Storage in Human Heart Transplantation

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    PURPOSE: Pre-clinical studies have shown that ex vivo non-ischemic heart preservation (NIHP) method can be safely used for 24 hours. This state-of-the-art method has never been applied on humans. ໿໿The primary objective of the study was to evaluate the efficacy and safety of the NIHP method on early and late human heart allograft function compared with static cold storage (SCS). METHODS: We performed a prospective, open-label, non-randomised phase II study. All adult recipients listed for heart transplantation were included, unless they met any exclusion criteria. The primary endpoint was a composite of survival free of severe primary graft dysfunction, free of ECMO use within 7 days, and free of acute cellular rejection ≥2R within 180 days. Secondary endpoints were I/R-tissue injury, immediate graft function, and adverse event. Of the 37 eligible patients, nine were assigned to the NIHP method and 28 to SCS. RESULTS: The median age was 51 years (interquartile range (IQR), 37-58) for the donors and 56 years (IQR, 46 - 63) for the recipients. The median preservation time was significant longer for the NIHP group, 251 min (IQR, 219-269) compared with the SCS group, 199 min (IQR, 164 - 227), P=0.008. Over the first three months, all of the patients assigned to the NIHP group achieved event-free survival, compared with 21 (75%) of those assigned to the SCS group (Kaplan-Meier estimate of event free survival 75% (95% CI 55-87%); P=0.124). CK-MB assessed 6±2 h after ending perfusion was 77 (IQR, 54-101) ng/mL for the NIHP group compared with 137 (IQR, 73-196) ng/mL for the SCS group, P=0.030. Four (16%) death within six months after transplantation and three (12%) cardiac-related adverse events were reported in the SCS group compared with no deaths or cardiac-related adverse events in the NIHP group. CONCLUSION: This first-in-human study shows the NIHP method's feasibility and safety for use in the clinic of heart transplantation

    Kinetic limitations in the Mg-Si-H system

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    Magnesium silicide (Mg2Si) has attracted interest as a hydrogen storage material due to favorable thermodynamics (ΔHdesorption = 36 kJ/mol H2) for room temperature operation. To date, direct hydriding of Mg2Si under hydrogen gas to form MgH2 and Si has only been attempted at low pressure and has been hindered by poor kinetics of absorption. In this paper we study the dehydrogenation reaction with in-situ neutron powder diffraction and present results of our attempts to hydrogenate Mg2Si under both hydrogen and deuterium gas up to temperatures of 350 °C and pressures of 1850 bar. Even under these extreme absorption conditions Mg2Si does not absorb any measureable quantity of hydrogen or deuterium
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