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Hydrogen is considered to be a promising energy carrier to solve the issue of energy crisis. Molybdenum carbide (MoxC) is the typical material, which has similar properties of Pt and thought to be an attractive alternative to noble metals for H2 evolution. The study of MoxC as alternative catalyst for H2 production is almost focused on electrocatalytic field, while the application of MoxC as a co-catalyst in photocatalytic H2 evolution has received in-depth research in recent years. https://www.selleckchem.com/products/r-hts-3.html Particularly, MoxC exhibits significant enhancement in the H2 production performance of semiconductors under visible light irradiation. However, a review discussing MoxC serving as a co-catalysts in the photocatalytic H2 evolution is still absent. Herein, the recent progress of MoxC on photocatalytic H2 evolution is reviewed. Firstly, the preparation methods including chemical vapor deposition, temperature programming, and organic-inorganic hybridization are detailly summarized. Then, the fundamental structure, electronic properties, and specific conductance of MoxC are illustrated to illuminate the advantages of MoxC as a co-catalyst for H2 evolution. Furthermore, the different heterojunctions formed between MoxC and other semiconductors for enhancing the photocatalytic performance are emphasized. Finally, perspectives regarding the current challenges and the future research directions on the improvement of catalytic performance of MoxC-based photocatalysts are also presented. Bisphosphonates are widely used in the treatment of osteoporosis in postmenopausal women and older men. In clinical trials they have been shown to reduce fractures in women with osteoporosis and there is increasing evidence that they are also effective in women with osteopenia, in whom the majority of fractures occur. In addition to their role as initial therapy in individuals at increased risk of fracture, bisphosphonates are used as sequential therapy after treatment with anabolic drugs. There are no head-to head studies to compare the anti-fracture efficacy of different bisphosphonates, but there is limited evidence that zoledronate treatment results in greater increases in BMD than risedronate or alendronate. This, together with the need for less frequent administration of zoledronate, supports its wider use in clinical practice, particularly if longer dosing intervals than those currently recommended are shown to be effective. Marfan syndrome (MFS) is an autosomal genetic disorder of connective tissue, due to alterated fibrillin-1. The aim of our study was to verify the rate of fractures in children with MFS in correlation to bone mineral density and compare the prevalence to the general population in the same latitude. We enrolled 80 patients (37 girls and 43 boys) with the diagnosis of Marfan syndrome, median age 10 y (3 to 17 years). Fracture occurrence was inferred from medical records of patients with MFS. Bone mineral density (BMD) was measured at lumbar spine, femoral neck and total femur by dual-energy x-ray absorptiometry. BMD values were expressed as z-scores, and adjusted for height using height-for-age z-scores. Bone turnover markers and vitamin D were measured. We assessed incidence of fracture in general pediatric population of our geographic area (45°N latitude). A total of 24 fractures were recorded in 21 patients (15 boys and 6 girls), involving both short and long bones, due to mild or moderate trauma. An incidence estimate has been calculated for each year, and an average incidence of 29.2/1000 MFS patients was obtained, markedly higher (P=0.034) than the incidence of fracture calculated in the same geographical area in pediatric patients (15.8/1000). We did not detect differences in anthropometric measurements, BMD values and biochemical indices between patients who fractured and patients who did not. Similarly, no differences were found between patients on losartan therapy and patients not in treatment for the same variables. In conclusion, the incidence of fractures was higher in patients with MFS compared to general population of the same age and latitude. The management of MFS must account bone status health and start strategies of fracture prevention. Protein aggregation plays important roles in life science as, for instance, those associated to neurodegenerative diseases. Although extensive efforts have been done to elucidate all the possible variables related to the aggregation process, much has yet to be done to unveil the main pathways governing protein assembling. In the current work, we induce bovine serum albumin (BSA) association, at pH 3.7, by adding sodium dodecyl sulfate (SDS) and sodium perfluorooctanoate (SPFO) surfactants to BSA solution as promoters of protein aggregation. Firstly, we combine molecular dynamic simulations (MD) to obtain a partially unfolded state of BSA's monomer at the acid pH and small angle X-ray scattering (SAXS) to validate the model. Interestingly, we found by SAXS that at pH 3.7 BSA monomers coexist with dimers in surfactant-free solution. Upon SDS and SPFO addition, the partial unfolded BSA may evolve to large aggregates depending on surfactant concentration. The threshold occurs at 301 and 451 SDSBSA and SPFOBSA molar ratio, respectively, according to turbidity, Thioflavin (ThT) fluorescence, synchrotron radiation circular dichroism (SRCD), SAXS and scanning electron microscopy (SEM) experiments. BSA aggregates are larger in the presence of SDS and structurally more defined upon SPFO binding. Isothermal titration calorimetry (ITC) results give support to infer that both surfactants initially bind to the BSA macromolecule forming a complex. Then, these complexes self-associate towards supramolecular aggregates. Taking into account the physicochemical characteristics of both surfactants and also MD simulations we may suggest that the higher rigidity of the fluorinated chains in respect to hydrogenated ones is crucial to induce more ordered and smaller BSA's aggregates. Our results thus evidence that the ligand structural flexibility might be of a key importance in the pathway of protein aggregation and may pave the way to better understand the early steps of neurodegenerative disorders.

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