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  • Salinas Henneberg heeft een update geplaatst 2 weken, 2 dagen geleden

    In order to explore the angular strain role on the ability of Be to form strong beryllium bonds, a theoretical study of the complexes of four beryllium derivatives of orthocloso-carboranes with eight molecules (CO, N2, NCH, CNH, OH2, SH2, NH3, and PH3) acting as Lewis bases has been carried out at the G4 computational level. The results for these complexes, which contain besides Be other electron-deficient elements, such as B, have been compared with the analogous ones formed by three beryllium salts (BeCl2, CO3Be and SO4Be) with the same set of Lewis bases. The results show the presence of large and positive values of the electrostatic potential associated to the beryllium atoms in the isolated four beryllium derivatives of ortho-carboranes, evidencing an intrinsically strong acidic nature. In addition, the LUMO orbital in these systems is also associated to the beryllium atom. These features led to short intermolecular distances and large dissociation energies in the complexes of the beryllium derivatives of ortho-carboranes with the Lewis bases. Notably, as a consequence of the special framework provided by the ortho-carboranes, some of these dissociation energies are larger than the corresponding beryllium bonds in the already strongly bound SO4Be complexes, in particular for N2 and CO bases. The localized molecular orbital energy decomposition analysis (LMOEDA) shows that among the attractive terms associated with the dissociation energy, the electrostatic term is the most important one, except for the complexes with the two previously mentioned weakest bases (N2 and CO), where the polarization term dominates. Hence, these results contribute to further confirm the importance of bending on the beryllium environment leading to strong interactions through the formation of beryllium bonds.The present study aimed to evaluate the accuracy of digitally designed surgical splints generated with milling technology (material subtractive procedure) and with 3D printing technology (material additive procedure) through a customized approach in the planning of surgical orthognathic splints. Cone beam computed tomography (CBCT) examinations and scanned dental models of 10 subjects who had required surgical treatment of skeletal malocclusion were included. Simulation of the orthognathic surgery was performed according to dento-skeletal and aesthetic characteristics of the subjects and the visual treatment objective (VTO), using Dolphin3D software (Dolphin Imaging, version 11.0, Chatsworth, CA, USA). Afterward, the Appliance Designer software (3Shape A/S, Copenhagen, Denmark) was used to digitally design the surgical splints that were generated twice using laser stereolithography technology (DWS 0.29D, DWS, Vicenza, Italy) and milling technology (Sirona inLab MC X5). Finally, each physical splint was digitalized using a desktop scanner (D500 3D, 3Shape A/S, Copenhagen, Denmark) in order to perform deviation analysis using the original project as a reference. The relative percentage of matching (trueness) was calculated (Geomagic Control X software (3D Systems, version 2018.1.1, 3D Systems, Rock Hill, SC, USA). 1400W supplier An Independent Student’s t-test was used to statistically analyze the data. The milled splints showed a lower value of root to mean square (RMS) relative to the original project (0.20 mm ± 0.018) compared to the prototyped splints (0.31 ± 0.021) (p less then 0.001). According to the present findings, surgical splints generated with milling technology present higher trueness compared with 3D printing technology.The control of virgin olive oil (VOO) freshness requires new tools that reflect the diverse chemical changes that take place during the market period. Fluorescence spectroscopy is one of the techniques that has been suggested for controlling virgin olive oil (VOO) freshness during its shelf-life. However, a complete interpretation of fluorescence spectra requires analyzing multiple parameters (chemical, physical-chemical, and sensory) to evaluate the pace of fluorescence spectral changes under moderate conditions with respect to other changes impacting on VOO quality. In this work, four VOOs were analyzed every month with excitation-emission fluorescence spectra. The same samples were characterized with the concentration of fluorophores (phenols, tocopherols, chlorophyll pigments), physical-chemical parameters (peroxide value, K232, K270, free acidity), and sensory attributes (medians of defects and of the fruity attribute). From the six components extracted with parallel factor analysis (PARAFAC), two components were assigned to chlorophyll pigments and those assigned to tocopherols, phenols, and oxidation products were selected for their ability to discriminate between fresh and aged oils. Thus, the component assigned to oxidation products correlated with K270 in the range 0.80-0.93, while the component assigned to tocopherols-phenols correlated with the fruity attribute in the range 0.52-0.90. The sensory analysis of the samples revealed that the changes of these PARAFAC components occurred at the same time as, or even before, the changes of the sensory characteristics.Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD), with prevalence increasing at an alarming rate worldwide and today, there are no known cures. The pathogenesis of DKD is complex, influenced by genetics and the environment. However, the underlying molecular mechanisms that contribute to DKD risk in about one-third of diabetics are still poorly understood. The early stage of DKD is characterized by glomerular hyperfiltration, hypertrophy, podocyte injury and depletion. Recent evidence of glomerular endothelial cell injury at the early stage of DKD has been suggested to be critical in the pathological process and has highlighted the importance of glomerular intercellular crosstalk. A potential mechanism may include reactive oxygen species (ROS), which play a direct role in diabetes and its complications. In this review, we discuss different cellular sources of ROS in diabetes and a new emerging paradigm of endothelial cell dysfunction as a key event in the pathogenesis of DKD.

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