We report the synthesis, characterization, and iodine capture application of a novel thorium-organic nanotube, TSN-626, [ThO(OH)(CHNO)(CHO)(HO)]·3HO. The classification as a metal-organic nanotube (MONT) distinguishes it as a rare and reduced dimensionality subset of metal-organic frameworks (MOFs); the structure is additionally hallmarked by low node connectivity. TSN-626 is composed of hexameric thorium secondary building units and mixed O/N-donor isonicotinate ligands that demonstrate selective ditopicity, yielding both terminating and bridging moieties.
View Article and Find Full Text PDFWe present the active learning configuration interaction (ALCI) method for multiconfigurational calculations based on large active spaces. ALCI leverages the use of an active learning procedure to find important electronic configurations among the full configurational space generated within an active space. We tested it for the calculation of singlet-singlet excited states of acenes and pyrene using different machine learning algorithms.
View Article and Find Full Text PDFWe report the synthesis and characterization of the first plutonium metal-organic framework (MOF). Pu-UiO-66 expands the established UiO-66 series, which includes transition metal, lanthanide, and early actinide elements in the hexanuclear nodes. The thermal stability and porosity of Pu-UiO-66 were experimentally determined, and multifaceted computational methods were used to corroborate experimental values, examine inherent defects in the framework, decipher spectroscopic signatures, and elucidate the electronic structure.
View Article and Find Full Text PDFPredicting and understanding the chemical bond is one of the major challenges of computational quantum chemistry. Kohn-Sham density functional theory (KS-DFT) is the most common method, but approximate density functionals may not be able to describe systems where multiple electronic configurations are equally important. Multiconfigurational wave functions, on the other hand, can provide a detailed understanding of the electronic structures and chemical bonds of such systems.
View Article and Find Full Text PDFspecies are aerobic, gram-positive, filamentous, partially acid-fast actinomycetes which are found worldwide in soil and decaying organic plant matter. When they infect human beings, they generally enter through the respiratory tract and then disseminate systemically. Rarely has a primary infection occurred as the result of direct inoculation.
View Article and Find Full Text PDFStructural deformation and collapse in metal-organic frameworks (MOFs) can lead to loss of long-range order, making it a challenge to model these amorphous materials using conventional computational methods. In this work, we show that a structure-property map consisting of simulated data for crystalline MOFs can be used to indirectly obtain adsorption properties of structurally deformed MOFs. The structure-property map (with dimensions such as Henry coefficient, heat of adsorption, and pore volume) was constructed using a large data set of over 12000 crystalline MOFs from molecular simulations.
View Article and Find Full Text PDFCutaneous and systemic plasmacytosis (CSP) is a rare disorder of unknown etiology characterized by cutaneous polyclonal plasma cell infiltrates associated with various extracutaneous involvement and polyclonal hypergammaglobulinemia. Here, we report on a 54-year-old male patient with chronic renal insufficiency who presented with disseminated reddish-brown macules and plaques on the face and trunk. In our evaluation, he was found to have lymphadenopathy, polyclonal hypergammaglobulinemia; benign plasma cell infiltration involving the skin, bone marrow, and retroperitoneal area; and renal amyloidosis.
View Article and Find Full Text PDFThe increase rate of utilization of branched-chain amino acids (BCAA) by muscle is reduced to its plasma concentration during prolonged exercise leading to glycogen. BCAA supplementation would reduce the serum activities of intramuscular enzymes associated with muscle damage. To examine the effects of BCAA administration on fatigue substances (serotonin, ammonia and lactate), muscle damage substances (CK and LDH) and energy metabolism substances (FFA and glucose) after endurance exercise.
View Article and Find Full Text PDFChronic exposure of human skin to solar ultraviolet (UV) radiation causes photoaging. Naturally occurring phytochemicals are known to have anti-photoaging effects. The present study examined the effect of mangiferin isolated from Anemarrhena asphodeloides on wrinkle formation, skin thickness, and changes in collagen fibers in hairless mice.
View Article and Find Full Text PDFTumor necrosis factor α (TNF-α), which is a primary cytokine responsible for inflammatory responses in skin, induces the synthesis of matrix metalloproteinase-9 (MMP-9), which causes skin aging. The protective effects of 3-deoxysappanchalcone against TNF-α-induced damage was investigated using human skin keratinocytes. The results showed that 3-deoxysappanchalcone inhibited MMP-9 expression at the protein and mRNA level, by blocking the activation of activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB).
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