X‐ray and Synchrotron FTIR Studies of Partially Decomposed Magnesium Borohydride

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X-ray and Synchrotron FTIR Studies of Partially Decomposed Magnesium Borohydride

Magnesium borohydride (Mg(BH4)(2)) is an attractive compound for solid-state hydrogen storage due to its lucratively high hydrogen densities and theoretically low operational temperature. Hydrogen release from Mg(BH4)(2) occurs through several steps. The reaction intermediates formed at these steps have been extensively studied for a decade. In this work, we apply spectroscopic methods that have rarely been used in such studies to provide alternative insights into the nature of the reaction intermediates. The commercially obtained sample was decomposed in argon flow during thermogravimetric analysis combined with differential scanning calorimetry (TGA-DSC) to differentiate between the H-2-desorption reaction steps. The reaction products were analyzed by powder X-ray diffraction (PXRD), near edge soft X-ray absorption spectroscopy at boron K-edge (NEXAFS), and synchrotron infrared (IR) spectroscopy in mid- and far-IR ranges (SR-FTIR). Up to 12 wt% of H-2 desorption was observed in the gravimetric measurements. PXRD showed no crystalline decomposition products when heated at 260-280 degrees C, the formation of MgH2 above 300 degrees C, and Mg above 320 degrees C. The qualitative analysis of the NEXAFS data showed the presence of boron in lower oxidation states than in (BH4)(-). The NEXAFS data also indicated the presence of amorphous boron at and above 340 degrees C. This study provides additional insights into the decomposition reaction of Mg(BH4)(2)

Complex transition metal hydrides incorporating ionic hydrogen: Synthesis and characterization of Na2Mg2FeH8 and Na2Mg2RuH8

A new class of quaternary complex transition metal hydrides (Na2Mg2TH8 (T = Fe, Ru)) have been synthesized and their structures determined by combined synchrotron radiation X-ray and powder neutron diffraction. The compounds can be considered as a link between ionic and complex hydrides in terms of incorporating independently coordinated ionic and covalent hydrogen. These novel isostructural complex transition metal hydrides crystallize in the orthorhombic space group Pbam, where the octahedral complex hydride anion is surrounded by a cubic array of four Mg2+ and four Na+ cations, forming distinct two-dimensional layers. An intriguing feature of these materials is the distorted octahedral coordination of the isolated H− anions by four Na+ and two Mg2+ cations, which form layers between the transition metal containing layers. The vibrational modes of the H− anions and complex hydride anion are independently observed for the first time in a quaternary complex transition metal hydride system by Raman and IR spectroscopy

Dynamics of Gut Microbiota and Clinical Variables after Ketogenic and Mediterranean Diets in Drug-Naïve Patients with Type 2 Diabetes Mellitus and Obesity

Type 2 diabetes mellitus (T2DM), the most common form of diabetes, is a progressive chronic metabolic disease that has increasingly spread worldwide, enhancing the mortality rate, particularly from cardiovascular diseases (CVD). Lifestyle improvement through diet and physical activity is, together with drug treatment, the cornerstone of T2DM management. The Mediterranean diet (MD), which favors a prevalence of unprocessed vegetable foods and a reduction in red meats and industrial foods, without excluding any food category, is usually recommended. Recently, scientific societies have promoted a very low-calorie ketogenic diet (VLCKD), a multiphasic protocol that limits carbohydrates and then gradually re-introduces them, with a favorable outcome on body weight and metabolic parameters. Indeed, gut microbiota (GM) modifications have been linked to overweight/obesity and metabolic alterations typical of T2DM. Diet is known to affect GM largely, but only a few studies have investigated the effects of VLCKD on GM, especially in T2DM. In this study, we have compared anthropometric, biochemical, lifestyle parameters, the quality of life, and the GM of eleven patients with recently diagnosed T2DM and overweight or obesity, randomly assigned to two groups of six and five patients who followed the VLCKD (KETO) or hypocaloric MD (MEDI) respectively; parameters were recorded at baseline (T0) and after two (T2) and three months (T3). The results showed that VLCKD had more significant beneficial effects than MD on anthropometric parameters, while biochemical improvements did not statistically differ. As for the GM, despite the lack of significant results regarding the alpha and beta diversity, and the Firmicutes/Bacteroidota ratio between the two groups, in the KETO group, a significant increase in beneficial microbial taxa such as Verrucomicrobiota phylum with its members Verrucomicrobiae, Verrucomicrobiales, Akkermansiaceae, and Akkermansia, Christensenellaceae family, Eubacterium spp., and a reduction in microbial taxa previously associated with obesity (Firmicutes and Actinobacteriota) or other diseases (Alistipes) was observed both at T2 and T3. With regards to the MEDI group, variations were limited to a significant increase in Actinobacteroidota phylum at T2 and T3 and Firmicutes phylum at T3. Moreover, a metagenomic alteration linked to some metabolic pathways was found exclusively in the KETO group. In conclusion, both dietary approaches allowed patients to improve their state of health, but VLCKD has shown better results on body composition as well as on GM profile

INvolvement of breast CAncer patients during oncological consultations: a multicentre randomised controlled trial--the INCA study protocol.

INTRODUCTION: Studies on patient involvement show that physicians make few attempts to involve their patients who ask few questions if not facilitated. On the other hand, the patients who participate in the decision-making process show greater treatment adherence and have better health outcomes. Different methods to encourage the active participation during oncological consultation have been described; however, similar studies in Italy are lacking. The aims of the present study are to (1) assess the effects of a preconsultation intervention to increase the involvement of breast cancer patients during the consultation, and (2) explore the role of the attending companions in the information exchange during consultation. METHODS AND ANALYSIS: All female patients with breast cancer who attend the Oncology Out-patient Services for the first time will provide an informed consent to participate in the study. They are randomly assigned to the intervention or to the control group. The intervention consists of the presentation of a list of relevant illness-related questions, called a question prompt sheet. The primary outcome measure of the efficacy of the intervention is the number of questions asked by patients during the consultation. Secondary outcomes are the involvement of the patient by the oncologist; the patient's perceived achievement of her information needs; the patient's satisfaction and ability to cope; the quality of the doctor-patient relationship in terms of patient-centeredness; and the number of questions asked by the patient's companions and their involvement during the consultation. All outcome measures are supposed to significantly increase in the intervention group. ETHICS AND DISSEMINATION: The study was approved by the local Ethics Committee of the Hospital Trust of Verona. Study findings will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01510964

Metal hydrides for concentrating solar thermal power energy storage

The development of alternative methods for thermal energy storage is important for improving the efficiency and decreasing the cost for Concentrating Solar-thermal Power (CSP). We focus on the underlying technology that allows metal hydrides to function as Thermal Energy Storage (TES) systems and highlight the current state-of-the-art materials that can operate at temperatures as low as room-temperature and as high as 1100 oC. The potential of metal hydrides for thermal storage is explored while current knowledge gaps about hydride properties, such as hydride thermodynamics, intrinsic kinetics and cyclic stability, are identified. The engineering challenges associated with utilising metal hydrides for high-temperature thermal energy storage are also addressed