CIFDock A novel CHARMMbased adaptable receptorflexible ligand docking method

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Iodide homeostasis and thyroid hormone metabolism in the brain are potentially related to changes in the activity of the sodium iodide symporter (NIS). No radiotracers are currently available for imaging brain NIS activity. Here, we synthesized 6-[124I]iodo-9-pentylpurine that can noninvasively measure iodide efflux from the brain and showed that the efflux rate of [124I]I- in NIS knockout mice was 84% lower than that of wild-type mice. Thus, 6-[124I]iodo-9-pentylpurine would be useful for imaging brain NIS activity.In this work, we introduce a new two-dimensional chip-based high-performance liquid chromatography (2D chip-HPLC) approach, which enables multiple transfers from the first dimension effluent onto the column head of the second separation dimension. By merging injection, separation, and detection features on a fused silica chip in a dead volume-free manner, all extra-column peak dispersion effects can be reduced to an absolute minimum. The application of intrinsic fluorescence detection with excitation in the deep-UV spectral region and electrospray ionization mass spectrometry after the first and second separation dimension, respectively, enables the label-free analysis of complex samples, as exemplarily shown for a pesticide mixture and a tryptic digest.A general method has been developed for the formation of glycosyl chlorides and bromides from picolinic esters under mild and neutral conditions. Benchtop stable picolinic esters are activated by a copper(II) halide species to afford the corresponding products in high yields with a traceless leaving group. Rare β glycosyl chlorides are accessible via this route through neighboring group participation. Additionally, glycosyl chlorides with labile protecting groups previously not easily accessible can be prepared.Sodium titanium oxide with a spinel-type structure is suitable for the stable sodium-intercalation host for the negative electrode of sodium-ion batteries, such as the spinel-type lithium titanium oxide (Li4Ti5O12, LTO) material for lithium-ion batteries. Recently, this has been partly discovered as the Na3LiTi5O12 (NTO) phase in the LTO particle. However, the single-phase NTO material has never been obtained, preventing accurate material characterizations and applications. Here, we successfully realized the NTO material with the single-phase by the chemical sodium insertion-extraction process. The chemical sodium-inserted LTO material is well converted to the pure NTO phase in the single particle level, via following chemical oxidation by water. The purified material was about 97 mol % of NTO as the single-phase spinel structure with a = 8.746 Å. click here The basic lattice framework of the prepared NTO was confirmed to be the same as that of the LTO. The single-phase NTO electrode shows 0.8 V versus Na+/Na of the Na-insertion and extraction potential, and 99.4% of Na-insertion capacity with 99.7% of Coulombic efficiency during 200 cycles of the Na-ion half-cell experiment. Further, the Na2Fe2(SO4)3/NTO full-cell shows 3 V-class stable charge-discharge character during 100 cycles. This excellent stability of Na-insertion and extraction properties of single-phase NTO extends the range of constructing safe and stable high-voltage oxide-based sodium-ion battery cells for practical use.Owing to superior sorption properties, structural variability, and versatility, metal-organic frameworks (MOFs) are used as sensing materials with both high selectivity and sensitivity. Herein, integrating a MOF with a polymer, a multilayered photonic crystal (PC) sensor, which is composed of NH2-MIL-88B nanocrystals and poly(styrene-acrylic acid) nanoparticles, is fabricated. Synthetically, by taking advantage of the sensitive breathing effect of the MOF and excellent stimuli-response of the copolymer, the sensor outputs significant optical signals that can be visually recognized and captured with the assistance of the spectrum with the detection limits of 3.70, 0.87, 0.42, and 0.22 g/m3 when exposed to benzene, toluene, ethylbenzene, and xylene (BTEX), respectively. Thanks to the porous construction and ultrathin feature, the PC sensor reaches a sensing balance within 3 s in BTEX streams and restores its initial state immediately after the rapid volatilization of the vapors. The function of the MOF material is confirmed by comparing the sensing properties of MOF/polymer PC with those of the SiO2/polymer one. In addition, as the designed MOF/polymer-based PC sensor shows different spectrum characteristics compared with those of other reported MOF-based ones, finite element simulation technology is adopted to help explain the relationship between optical property and material structure feature of the multilayered PC structure.Painted environmental surfaces are prone to microbiological colonization with potential coating deterioration induced by the microorganisms. Accurate mechanistic models of these interactions require an understanding of the heterogeneity in which the deterioration processes proceed. Here, unsaturated biofilms (i.e., at air/solid interfaces) of the yeast Papiliotrema laurentii were prepared on polyether polyurethane (PEUR) and polyester-polyether polyurethane (PEST-PEUR) coatings and incubated for up to 33 days at controlled temperature and humidity with no additional nutrients. Transmission micro-Fourier transform infrared microscopy (μFTIR) confirmed preferential hydrolysis of the ester component by the biofilm. Atomic force microscopy combined with infrared nanospectroscopy (AFM-IR) was used to analyze initial PEST-PEUR coating deterioration processes at the single-cell level, including underlying surfaces that became exposed following cell translocation. The results revealed distinct deterioration features mechanisms and biofilm physiology at polymer coating interfaces.Pollution of water with heavy metals is a global environmental problem whose impact is especially severe in developing countries. Among water-purification methods, adsorption of heavy metals has proven to be simple, versatile, and cost-effective. However, there is still a need to develop adsorbents with a capacity to remove multiple metal pollutants from the same water sample. Herein, we report the complementary adsorption capacities of metal-organic frameworks (here, UiO-66 and UiO-66-(SH)2) and inorganic nanoparticles (iNPs; here, cerium-oxide NPs) into composite materials. These adsorbents, which are spherical microbeads generated in one step by continuous-flow spray-drying, efficiently and simultaneously remove multiple heavy metals from water, including As(III and V), Cd(II), Cr(III and VI), Cu(II), Pb(II), and Hg(II). We further show that these microbeads can be used as a packing material in a prototype of a continuous-flow water treatment system, in which they retain their metal-removal capacities upon regeneration with a gentle acidic treatment.