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Mycobacterium tuberculosis (Mtb), the pathogen of tuberculosis, has latently infected about one-third of the world’s population and may lead to severe clinical symptoms and death. The WhiB4 protein, a transcription factor, plays a crucial role in the survival and pathology of Mtb. WhiB4 leads to the condensation of mycobacterial nucleoids and regulates the expression of genes involved in central metabolism, respiration, and maintaining redox homeostasis. Here, we report the solution structure of reduced apo-WhiB4 monomer, which consists of an unstructured N-terminal domain with four cysteine residues and a helix-turn-helix C-terminal domain that plays a major role in DNA binding. The C-terminal domain of WhiB4 binds DNA at the minor groove, with five positively charged lysine/arginine residues contacting DNA sugar-phosphate backbones through electrostatic interactions. AT-rich DNA sequences with narrower minor grooves are more preferred by WhiB4. The binding affinity of a single C-terminal domain of WhiB4 is weak. When oxidized, WhiB4 can form dimers and oligomers in different forms through disulfide bonds, which should significantly enhance its DNA binding ability through multivalent effect and change the local structure of target genes and influence their transcription. These structural features form the basis for WhiB4 to function as a redox-sensitive transcription factor in Mtb.

We present a first-principle molecular dynamics study on the uptake and hydration of sulfur dioxide on the dry and wet fully hydroxylated surfaces of (0001) alpha-quartz, which are a proxy for suspended silica dust in atmosphere. The average adsorption energy for SO2 is ~10 kcal/mol on both dry and wet surfaces. The adsorption is driven by hydrogen bonds formation between SO2 and the interfacial hydroxyl groups (on dry silica), or with water molecules (in the wet case). In the dry system, we report an additional electrostatic interaction between the interfacial hydroxyl oxygen and the sulfur atom, which further stabilize the adsorbate. On dry silica, the interfacial hydroxyl group coordinates SO2 yielding to a surface bounded bisulfite (Si-SO3H) complex. On the wet surface, SO2 reacts with water forming bisulfite (HSO3-), and the latter remains solvated inside the adsorbed water layer. The hydration barrier for sulfur oxide is 1 kcal/mol and 3 kcal/mol on the dry and wet silica, respectively, while for the backward reaction (i.e., bisulfite to SO2) the barrier is 6 kcal/mol on both surfaces. The modest backward barrier rationalizes earlier experimental findings showing no SO2 uptake on silicates. These results underline the importance of the surface hydroxylation and/or of adsorbed water layers for the SO2 uptake and its hydration on silica. Moreover, the hydration to bisulfite may prevent direct SO2 photochemistry and be an additional source of sulfate: this is especially relevant in atmosphere subject to high level of suspend mineral dust, intense solar radiation and atmospheric oxidizers.

Ansalactam A is an ansa macrolide natural product that contains a densely functionalized spiro-γ-lactam core containing three contiguous stereocenters. This unusual motif distinguishes it from other members of this family and represents a significant synthetic challenge. Herein, we report the development of a stereoselective formal [3+2] cycloaddition reaction for the construction of this key spiro-γ-lactam motif for the first time, thereby enabling access to the northern domain of ansalactam A.

The mixture of p-(methoxy)calix[n]arenes (n = 6, 7 or 8) was prepared in one step from p-methoxyphenol under basic conditions, and their fully methylated derivatives p-(dimethyloxy)calix[n]arenes (n = 6, 7 or 8) were also prepared and purified by column chromatography to indentify their structures. In this process, the single crystal of p-(dimethyloxy)calix[7]arene was obtained and its structure was confirmed. The proportion of p-(methoxy)calix[6]-, [7]-, and [8]-arenes in the mixture obtained from the reaction was investigated under different reaction conditions, and p-(methoxy)calix[6]- and [8]-arenes could be separated from the mixture by solvent extraction. In addition, the host-guest interaction of p-(dimethyloxy)calix[6]arene with methyl-4,4′-bipyridinium hexafluorophosphate in organic solvents was investigated.

Identifying motifs in promoter regions is crucial to our understanding of transcription regulation. Researchers commonly use known promoter features in a variety of species to predict promoter motifs. However the results are not particularly useful. Different species rarely have similar features in promoter binding sites. In this study, we adopt sequence analysis techniques to find the possible promoter binding sites among different species. We sought to improve the existing algorithm to suit the task of mining sequential patterns with specific number of gaps. Moreover, we discuss the implementation of proposed method in a distributed environment. The proposed method finds the transcription start sites (TSS) and extracts possible promoter regions from DNA sequences according to TSS. We derived the motifs in the possible promoter regions, while taking into account the number of gaps in the motifs to deal with unimportant nucleotides. The motifs generated from promoter regions using the proposed methodology were shown to tolerate unimportant nucleotides. A comparison with known promoter motifs verified the efficacy of the proposed method.

On the basis of cyclotrixylohydroquinoylene (CTX), a novel water-soluble phospholate-based CTX derivative (WPCTX) was prepared with facile synthetic procedure and satisfying yield. Several model guest molecules were selected to investigate WPCTX's host-guest properties. Based on the study of the host and model guest complexation, a tetraphenylethylene derivative from model guest was employed as a guest molecule (G) to form WPCTX⊃G nanoparticles (NPs) with WPCTX through further supramolecular self-assembly in water. Moreover, a hydrophobic fluorescent dye, Eosin Y(ESY) or Nile red (NiR), was encapsulated in WPCTX⊃G NPs to construct two types of artificial light-harvesting systems. Their high antenna effect demonstrated such NPs successfully mimicked light-harvesting systems in nature.

To recover zinc from electric arc furnace (EAF) dust, a process of primary normal pressure leaching and secondary alkaline pressure leaching is proposed. First, under the alkaline pressure leaching system, the experiment of pure zinc ferrite being reduced by iron powder was carried out. Under the optimal reduction conditions (i.e., temperature of 260 °C, NaOH concentration of 6 mol/L, liquid-to-solid ratio of 50 mL/g, and a 5-fold excess of iron powder), 89% of zinc was extracted. The iron in the reduced residue exists as a magnetite phase. Subsequently, the normal pressure leaching experiment was carried out with EAF dust as raw material, and 66% zinc was leached. The main phase of zinc in normal leaching residue was determined to be zinc ferrite. Then, the normal leaching residue was reduced by iron powder under the alkaline pressure leaching system, and 66.5% of zinc was extracted. After the two-stage leaching process, the leaching rate of zinc in EAF dust can achieve 88.7%. The alkaline pressure leaching solution can be returned as the normal pressure leaching solution, and the magnetite in the alkaline pressure leaching residue can be recovered by magnetic separation.

The ability to detect and characterize drug binding to a target protein is of high priority in drug discovery research. However, there are inherent challenges when the target of interest is an integral membrane protein (IMP). Assuming successful purification of the IMP, traditional approaches for measuring binding such as surface plasmon resonance (SPR) and fluorescence resonance energy transfer (FRET) have been proven valuable. However, the mass dependence of SPR signals may preclude the detection of binding events when the ligand has a significantly smaller mass than the target protein. In FRET-based experiments, protein labeling through modification may inadvertently alter protein dynamics. Graphene Bio-Electronic Sensing Technology (GBEST) aims to overcome these challenges. Label-free characterization takes place in a microfluidic chamber wherein a fluid lipid membrane is reconstituted directly above the GBEST sensor surface. By leveraging the high conductivity, sensitivity, and electrical properties of monolayer graphene, minute changes in electrostatic charges arising from the binding and unbinding of a ligand to a native IMP target can be detected in real time and in a mass-independent manner. Using crude membrane fractions prepared from cells overexpressing monocarboxylate transporter 1 (MCT1), we demonstrate the ability to (1) form a fluid lipid bilayer enriched with MCT1 directly on top of the GBEST sensor and (2) obtain kinetic binding data for an anti-MCT1 antibody. Further development of this novel technology will enable characterization of target engagement by both low- and high-molecular-weight drug candidates to native IMP targets in a physiologically relevant membrane environment.

Electrostatic reaction inhibition in heterogeneous catalysis emerges if charged reactants and products with similar charges are adsorbed on the catalyst and thus repel the approaching reactants. In this work, we study the effects of electrostatic inhibition on the reaction rate of unimolecular reactions catalyzed on the surface of a spherical model nanoparticle using particle-based reaction-diffusion simulations. Moreover, we derive closed rate equations based on an approximate Debye-Smoluchowski rate theory, valid for diffusion-controlled reactions, and a modified Langmuir adsorption isotherm, relevant for reaction-controlled reactions, to account for electrostatic inhibition in the Debye-Hückel limit. We study the kinetics of reactions ranging from low to high adsorptions on the nanoparticle surface and from the surface- to diffusion-controlled limits for charge valencies 1 and 2. In the diffusion-controlled limit, electrostatic inhibition drastically slows down the reactions for strong adsorption and low ionic concentration, which is well described by our theory. In particular, the rate decreases with adsorption affinity because, in this case, the inhibiting products are generated at a high rate. In the (slow) reaction-controlled limit, the effect of electrostatic inhibition is much weaker, as semiquantitatively reproduced by our electrostatic-modified Langmuir theory. We finally propose and verify a simple interpolation formula that describes electrostatic inhibition for all reaction speeds ("diffusion-influenced" reactions) in general.

OBJECTIVE: This study aimed to evaluate the effect of adiposity and fat distribution on the odds of elevated cardiovascular risk factors among adults with type 2 diabetes mellitus. METHODS: The present cross-sectional study included 2,427 adults with type 2 diabetes mellitus. Body fat was assessed by dual-energy x-ray absorptiometry. Multivariate-adjusted logistic regression was used to estimate effects of adiposity parameters on elevated hemoglobin A(1c) (HbA(1c), ≥7.0%), hypertension (blood pressure ≥140/90 mmHg), and elevated low-density lipoprotein (LDL) cholesterol (≥2.6 mmol/L). RESULTS: The multivariable-adjusted odds ratio (OR) for elevated HbA(1c) was 0.82 (95% CI: 0.70–0.96) for each SD increase in leg fat mass. The multivariable-adjusted OR for hypertension was 1.15 (95% CI: 1.00–1.32) for each SD increase in android fat mass. Multivariable-adjusted ORs for elevated LDL cholesterol ranged from 1.16 (95% CI: 1.00–1.35) to 1.27 (95% CI: 1.06–1.51) for each SD increase in arm and android fat mass and percentage of total, truncal, arm, and android fat. Each SD increase in BMI, truncal-to-leg fat ratio, and android-to-gynoid fat ratio was significantly associated with increased risks of elevated HbA(1c), hypertension, and elevated LDL cholesterol. CONCLUSIONS: Subcutaneous fat in the lower body was associated with a more favorable glycemic profile, but not blood pressure or lipid profile, whereas central adiposity was associated with poor control of cardiovascular risk factors among patients with type 2 diabetes mellitus.

Inorganic perovskite absorbers are promising candidates for next-generation photovoltaics due to their good thermal and light stabilities. Halide-mixed CsPbIxBr3−x reach a compromise between its structural tolerance and absorption edge, yet the power conversion efficiencies (PCEs) of the asfabricated cells can be considerably limited by the nonideal quality of solution-processed films. Here we demonstrated a fumigation strategy on colloidal perovskite films using dual-O-donor ethyl acetate (EA). By in-situ monitoring this stage with grazing-incidence wide-angle X-ray scattering technology, we reveal that EA fumigation would impose ripening barrier on colloidal inorganic perovskites and hence slow down the nucleation rate, leading to an intermediate state for processing high-crystallinity and oriented perovskite films with improved photophysical properties. An optimized PCE of 16.6% was finally yielded upon wide-bandgap (1.9 eV) perovskite absorber.

The element partitioning in a Pb−Bi concentrate oxygen-rich bath smelting process was studied using thermodynamic equilibrium simulation method. Effects of oxygen to feed ratio (OFR) and sulfur dioxide partial pressure (pSO2) on the partitionings of Bi, Pb, As, Sb, Cu and Ag were analyzed and compared with industrial data. The results suggested that the optimal OFR was between 6.3 and 6.8 kmol/t to maximize Bi, Pb, Cu and Ag partitioning in the metal phase. Further increase of OFR led to the drop of metal partitioning and increase of slag liquidus temperature. High pSO2 led to high deportment of Bi and Pb in the gas phase mainly in the form of sulfides, suggesting that a low pSO2 was conducive for reducing the dust ratio.

Microalgae have been immobilized in alginate matrixes for the ease of harvesting of the microalgae. However, not all microalgae thrive when immobilized. Immobilized cells are sensitive to the micro-environment in alginate matrixes. Hence, this study aims to improve the growth of immobilized cells and also ammoniacal-nitrogen (NH4 +-N) removal by adding growth medium in alginate beads during the immobilization process. Different strength of the Guillard’s f/2 medium (0%, 30%, 50%, and 100%) was enriched in alginate beads inoculated with Nannochloropsis sp. The immobilized cells were then cultivated in seawater with 1000 µM NH4 +-N as the sole nitrogen source. The growth and NH4 +-N uptake by immobilized cells enriched with different strength of f/2 medium were compared. There were no significant differences on specific growth rate and specific uptake rate of immobilized cells after nutrient enrichment in alginate beads. However, maximum cells attained and maximum NH4 +-N removed increased when strength of f/2 medium enriched in alginate beads was increased. Significantly higher maximum cells attained and maximum NH4 +-N removal were found in immobilized cells enriched with half strength of f/2 medium than those without nutrient enrichment. The present study demonstrated that nutrient enriched in alginate beads can be used by immobilized cells, and subsequently improves the performance of immobilized cells in marine water treatment and production of microalgal biomass simultaneously.

In this study, the coating process is employed on metal wire to help improve the friction resistant property of carbon fibers, thereby provides more application feasibility. The yarn coating technique for reinforcement and woven fabric process are used to produce carbon/stainless steel/polyester/polypropylene/acrylic (CSPPA) woven fabrics that are characterized with softness and a light weight. The constituent coated yarns exhibit good conductivity after being coated with a PP layer, and likewise strengthen the woven fabrics in terms of mechanical behavior of tensile strength, elongation, bending torsion, creep resistance, and wear-resistant properties. The test results indicate that in the woven process, samples retain good morphology. Due to PP sheath, the tensile strength of woven fabrics increases from 23 MPa to 42 MPa. Although the lamination layer numbers does not improve the EMI SE of woven fabrics, the EMI SE still reaches over 40 dB. The manufacturing design proposed in this study provides an innovative finishing for carbon fibers without affecting the intrinsic properties, and provides a greater range of application for carbon fibers.

Anaerobic digestion (AD) was employed to utilize fresh vinegar residue (FVR) in this study. The performance and microbial community structure at increasing organic loading rates (OLRs) were evaluated. The results showed that the mono-fermentation of FVR was unstable at high OLRs due to the high acidity and the high cellulose content of the raw material. The optimum OLR was 2.0 g VS/(L·d), with the maximum average methane yield at 216 mL /g VS. High OLRs (2.5 g VS/(L·d)) led to the irreversible inhibition of AD process, although digester ceased feeding during the recovering stage. The diversity of microbial community decreased at high OLRs. The relative abundance of major bacterial community at different OLRs also varied. The syntrophic volatile fatty acids (VFAs) oxidizing bacteria declined while the acid-producing bacteria became dominant. The close correlation between the AD process stability and the microbial community structure suggested that maintaining a rich and diverse microbial community was essential for the practical application of AD on vinegar residue (VR) utilization.

Pericarpium Citri Reticulatae (PCR), the mature fruit peel of Citrus reticulata Blanco and its different cultivars, is an important citrus by‐product with beneficial health and nutritive properties. However, due to the lack of value‐added methods for its development and utilization, a large amount of PCR is discarded or wasted. To explore a possibly more effective method to utilize PCR, we compared the chemical and biological differences before (CK) and after (CP) microbial transformation of PCR by Aspergillus niger. UPLC‐ESI‐MS/MS, HPLC, and LC‐MS methods were used to compare the chemical profiles of CK and CP. The results demonstrated that microbial biotransformation by A. niger could transform flavonoid compounds by utilizing the carbohydrate and amino acid nutrients in PCR. This could also promote the accumulation of polyhydroxyflavones compounds in CP. The antioxidant assay demonstrated that CP had significantly greater free radical‐scavenging activity than CK. The higher antioxidant activity of CP may result from the high level of flavonoids with associated phenolic hydroxyl groups. Microbial biotransformation is an effective method for improving the antioxidant capacity of PCR and may be effective and useful in other natural product situations., Microbial biotransformation is an effective method for improving the antioxidant capacity of PCR and may be effective and useful in other natural product situations.

The temperature-dependent rheological behaviors of five selected binary eutectic mixture sugar alcohols, with great potential for latent heat storage in the range of 353.15 K to 523.15 K, were investigated. It was found that the rheological behaviors of the mixture sugar alcohols depend on those of the pure compounds as well as their molar ratios. The two mixtures of xylitol (75 mol%)+erythritol and erythritol (84 mol%)+d-mannitol behave like pseudoplastic fluids with typical non-Newtonian shear-thinning behaviors, as indicated by the power law index of 0.99 (

4-Methylbenzylidene camphor (4-MBC), a widely used ultraviolet (UV) filter detected in various aquatic environments, has been shown to evoke estrogenic activity. In this study, the use of UV light-activated persulfate for 4-MBC degradation is evaluated for the first time. Our results showed that the combination of UV and persulfate (UV/persulfate) can significantly remove 4-MBC, with a pseudo-first-order rate constant (kobs) of 0.1349 min−1 under the conditions of [4-MBC]0 = 0.4 μM, [persulfate]0 = 12.6 μM, and initial pH = 7. The kobs and persulfate dose exhibited a linear proportional relationship in the persulfate dose range of 4.2–42 μM. The kobs remained similar at pH 5 and pH 7 but significantly decreased at pH 9. A radical scavenging test indicated that SO4−• was the dominant species in 4-MBC degradation; the second-order rate constant of SO4−• with 4-MBC was calculated to be (2.82 ± 0.05) × 109 M−1 s−1. During the UV/persulfate reaction, 4-MBC was continuously degraded, while SO4−• was gradually converted to SO42−. 4-MBC degradation involved the hydroxylation and demethylation pathways, resulting in the generation of transformation byproducts P1 (m/z 271) and P2 (m/z 243), respectively. The Microtox® acute toxicity test (Vibrio fischeri) showed increasing toxicity during the UV/persulfate degradation of 4-MBC. The 4-MBC degradation rate was markedly lower in outdoor swimming pool water than in deionized water.

Patchoulol is a tricyclic sesquiterpene widely used in perfumes and cosmetics. Herein, comprehensive engineering strategies were employed to construct an efficient yeast strain for patchoulol production. First, a platform strain was constructed via pathway modification. Second, three off-pathway genes were deleted, which led to significant physiological changes in yeast. Further, strengthening of the ergosterol pathway, enhancement of the energy supply, and a decrease in intracellular reactive oxygen species were implemented to improve the physiological status of yeast, demonstrating a new promotive relationship between ergosterol biosynthesis and synthesis of patchoulol. Moreover, patchoulol synthase was improved through protein modification and Mg2+ addition, reaching a final titer of 141.5 mg/L in a shake flask. Finally, a two-stage fermentation with dodecane addition was employed to achieve the highest production (1632.0 mg/L, 87.0 mg/g dry cell weight, 233.1 mg/L/d) ever reported for patchoulol in a 5 L bioreactor. This work lays a foundation for green and efficient patchoulol production.

In this study, a novel porous metal–organic framework (MOF) functionalized with amino and triazole moieties has been synthesized. Attributed to the high affinity to CO2 and unsaturated zinc centers, the MOF exhibits high catalytic activity for the CO2 to epoxide cycloaddition reaction, with a turnover number value of up to 10 000 per cycle, and can be reused at least for 20 cycles.

Heteroleptic copper(I)–phosphine complexes have attracted considerable attention because of their diverse structures, and photophysical and catalytic properties. In this work, a series of heteroleptic diimine–diphosphine Cu(I) complexes (C1–C10) were synthesized quantitively using the designed bipyridine (L1–L4) and bidentate polyphosphine (L5–L8) as functional ligands. These mixed ligand–copper(I) complexes were fully characterized by 1H and 13C NMR spectroscopy, electrospray ionization mass spectrometry (ESI-MS) and elemental analysis. The detailed structures of complexes C1, C2, C5, C6, C9 and C10 were confirmed by single-crystal X-ray diffraction analysis. Moreover, these phosphine–Cu(I) complexes exhibited intense emissions either in the solid state or in solution under UV light excitation. The emissive complexes C1–C4 displayed highly sensitive luminescence sensing towards silver ions in a quenching fashion (turn-off). Furthermore, all the phosphine-protected copper(I) complexes exhibited high catalytic activity towards azide–alkyne cycloaddition (CuAAC) in water.

It is highly desired but challenging to develop platinum group metal-free electrocatalysts for oxygen reduction reaction (ORR), which can promote the commercialization of fuel cell technology. To achieve this target, we report a one-step doping method to prepare S-doped Fe–N–C catalysts using zeolite imidazole framework (ZIF-8) and iron (III) thiocyanate (Fe(SCN)3) as precursor. Different from conventional doping approach, i.e. physical mixing, Fe(SCN)3 is in-situ added during ZIF-8 formation which would encapsulate Fe(SCN)3 molecules inside ZIF-8 to avoid structure destruction and create potential replacement of Zn ions by Fe ions to form uniform Fe–N4 complexes. As a result, the prepared S-doped Fe–N–C catalysts own large specific surface areas with a maximum value of 1326 ​m2 ​g−1 and a dual-scale porous structure that benefits mass transport. Significantly, the composition-optimized catalyst exhibits superior ORR activity in both 0.1 ​M HClO4 electrolyte and 0.1 ​M KOH electrolyte, in which the half-wave potential reaches 0.81 ​V and 0.92 ​V (vs. RHE), respectively. Remarkable stability is also attained, which loses 2 ​mV only after 10000 potential cycles in O2-saturated 0.1 ​M HClO4 and remains almost constant in O2-saturated 0.1 ​M KOH, surpassing commercial Pt/C catalyst in both acidic and alkaline medium.

Praeruptorin A (PA) is one of the active ingredients found in the dried root of Peucedanum praeruptorum Dunn, has been reported to possess anticancer effects against various types of cancer. However, the effect of PA on human hepatocellular carcinoma (HCC) remains uncleared. In this study, our results indicated that PA did not induce cytotoxicity or alter cell cycle distribution in human HCC cells (Huh-7, SK-Hep-1, and PLC/PRF/5 cells). Instead, PA inhibited the migration and invasion of human HCC cells while downregulating the expression of matrix metalloproteinase-1 (MMP1) and activating the extracellular signal-regulated kinase (ERK) signaling pathways. Furthermore, blocking the ERK signaling pathway through siERK restored the expression of MMP1 and the invasive ability of PA-treated HCC cells. In conclusion, our results demonstrate the antimetastatic activity of PA against human HCC cells, supporting its potential as a therapeutic agent of HCC treatments.

Flooding is an environmental stress that leads to a shortage of O2 that can be detrimental for plants. When flooded, deepwater rice grow floating adventitious roots to replace the dysfunctional soil-borne root system, but the features that ensure O2 supply and hence growth of aquatic roots have not been explored. We investigate the sources of O2 in aquatic adventitious roots and relate aerenchyma and barriers for gas diffusion to local O2 gradients, as measured by microsensor technology, to link O2 distribution in distinct root zones to their anatomical features. The mature root part receives O2 exclusively from the stem. It has aerenchyma that, together with suberin and lignin depositions at the water–root and cortex–stele interfaces, provides a path for longitudinal O2 movement toward the tip. The root tip has no diffusion barriers and receives O2 from the stem and floodwater, resulting in improved aeration of the root tip over mature tissues. Local formation of aerenchyma and diffusion barriers in the mature root channel O2 towards the tip which also obtains O2 from the floodwater. These features explain aeration of floating roots and their ability to grow under water.

The kinetic processes in nanoparticle-based catalysis are dominated by large fluctuations and spatiotemporal heterogeneities, in particular for diffusion-influenced reactions which are far from equilibrium. Here, we report results from particle-resolved reaction-diffusion simulations of steady-state bimolecular reactions catalyzed on the surface of a single, perfectly spherical nanoparticle. We study various reactant adsorption and diffusion regimes, in particular considering the crowding effects of the reaction products. Our simulations reveal that fluctuations, significant coverage cross-correlations, transient self-poisoning, related domain formation, and excluded-volume effects on the nanoparticle surface lead to a complex kinetic behavior, sensitively tuned by the balance between adsorption affinity, mixed 2D and 3D diffusion, and chemical reaction propensity. The adsorbed products are found to influence the correlations and fluctuations, depending on overall reaction speed, thereby going beyond conventional steric (e.g., Langmuir-like) product inhibition mechanisms. We summarize our findings in a state diagram depicting the nonlinear kinetic regimes by an apparent surface reaction order in dependence of the intrinsic reaction propensity and adsorption strength. Our study using a simple, perfectly spherical, and inert nanocatalyst demonstrates that spatiotemporal heterogeneities are intrinsic to the reaction-diffusion problem and not necessarily caused by any dynamical surface effects from the catalyst (e.g., dynamical surface reconstruction), as often argued.

The oxygen-rich bath smelting process of copper dross was simulated using Factsage software. It was found that the two-step simulation results agreed better with the industrial data, especially in the speiss. Bi, Pb, Sb, As, and Cu contents in the speiss by two-step simulation differed from the industrial data by 0.6 wt.%, 0.8 wt.%, 2.6 wt.%, 7.2 wt.%, and 8.6 wt.%, respectively. Two-step simulation results indicated that the speiss partitioning of Sb, As, and Cu increased from 60.1%, 32.3%, and 27.5% to 81.6%, 67.8%, and 47.2%, respectively, with the smelting temperature increasing from 1050 °C to 1250 °C. While the metal partitioning of Sb and Cu increased from 0% and 2.7% to 15.2% and 13.3%, respectively, with the separation temperature increasing from 400 °C to 700 °C.

A stoichiometry-controlled chirality induction was successfully achieved through coassemblies of amphiphilic tetraphenylethylene derivative TPEA, γ-cyclodextrin (γ-CD), and water-soluble pillar[5]a...

Objective Evaluation of glaucoma progression with OCT has been centered on the analysis of progressive retinal nerve fiber layer (RNFL) thinning over the parapapillary region and/or progressive ganglion cell inner plexiform layer (GCIPL) thinning over the macula. We investigated (1) whether combining the RNFL and GCIPL as a single layer (i.e., RNFL-GCIPL) for wide-field progression analysis outperforms wide-field progression analysis of the RNFL or the GCIPL, and (2) whether eyes with progressive RNFL-GCIPL thinning are at risk of visual field (VF) progression. Design Prospective, longitudinal study. Participants A total of 440 eyes from 236 glaucoma patients; 98 eyes from 49 healthy individuals. Methods OCT RNFL/GCIPL/RNFL-GCIPL thickness and VF measurements were obtained at ∼4-month intervals for ≥3 years. Progressive changes of the RNFL/GCIPL/RNFL-GCIPL thicknesses were analyzed over a wide field (12×9 mm2) covering the parapapillary region and the macula with trend-based progression analysis (TPA) controlled at a false discovery rate of 5%. VF progression was determined by the Early Manifest Glaucoma Trial criteria. Main Outcome Measures Proportions of eyes with progressive RNFL/GCIPL/RNFL-GCIPL thinning; hazard ratios (HRs) for development of VF progression. Results More eyes showed progressive RNFL-GCIPL thinning (127 eyes; 28.9%, 95% confidence interval [CI]: 23.9%–33.8%) than progressive RNFL thinning (74 eyes; 16.8%, 95% CI: 13.1%–20.6%) and progressive GCIPL thinning (26 eyes; 5.9%, 95% CI: 3.7%–8.1%) in the glaucoma group over the study follow-up. Progressive RNFL-GCIPL thinning was almost always detected before or simultaneously with progressive RNFL thinning or progressive GCIPL thinning. The specificity of TPA (estimated from the healthy group) for detection of progressive RNFL-GCIPL thinning, progressive RNFL thinning, and progressive GCIPL thinning was 83.7% (95% CI: 74.9%–92.4%), 94.9% (95% CI: 90.6%–99.2%), and 96.9% (95% CI: 93.5%–100.0%), respectively. Eyes with progressive RNFL-GCIPL thinning had a higher risk to develop possible (HR: 2.4, 95% CI: 1.2–5.0) or likely (HR: 4.6, 95% CI: 1.5–14.0) VF progression, with adjustment of covariates, compared with eyes without progressive RNFL-GCIPL thinning. Conclusions Progression analysis of RNFL-GCIPL thickness reveals a significant portion of progressing eyes that neither progression analysis of RNFL thickness nor GCIPL thickness would identify. Wide-field progression analysis of RNFL-GCIPL thickness is effective to inform the risk of VF progression in glaucoma patients.

People have increasingly rising health consciousness in recent years and researchers are thus devoted themselves to develop multi-functional textile products. In this study, stainless steel (SS) filaments are used for electromagnetic shielding effectiveness (EMSE) while polypropylene (PP) filaments are used for ultraviolet resistance and good mechanical properties. Spinning and weaving continuous formation techniques are employed to produce wrapped yarns with SS and PP filaments, after which a weaving process is employed for the preparation of SS/PP woven fabrics. The woven fabrics are tested for EMSE and UV resistance, examining the effect of the lamination-layer numbers and lamination-layer angles. Test results show that the optimal EMSE and UV resistance occur when SS/PP woven fabrics are laminated with two layers at 90 °. Not only focus on the mechanical performance, the proposed woven fabrics with good EMSE, UV resistance, and a light weight, and are good candidate for a variety of application as required. The proposed UV resistance and EMSE woven fabrics significantly increase the additional values of traditional textiles.

The YtfE protein catalyzes the reduction of NO to N2O, protecting iron-sulfur clusters from nitrosylation. The structure of YtfE has a two-domain architecture, with a diiron-containing C-terminal domain linked to an N-terminal domain, in which the function of the latter is enigmatic. Here, by using electron spin resonance (ESR) spectroscopy, we show that YtfE exists in two conformational states, one of which has not been reported. Under high osmotic stress, YtfE adopts a homogeneous conformation (C state) similar to the known crystal structure. In a regular buffer, the N-terminal domain switches between the C state and a previously unidentified conformation (C' state), the latter of which has more space at the domain interface to allow the trafficking of NO molecules and thus is proposed to be a functionally active state. The conformational switch between the C and C' states is pivotal for facilitating NO access to the diiron core.

The hydrogen trapping behaviors of dual nanometer-sized e-copper and TiC carbide precipitates have been investigated in a low-carbon steel. The precipitation fashions were controlled by quenching and tempering at different austenization temperatures. The nanostructures of the dual precipitates were characterized by high-resolution transmission electron microscopy and atom probe tomography. Hydrogen desorption was studied through thermal desorption analysis of steels electrochemically charged with hydrogen. The hydrogen trapping capability of the precipitates was investigated through the release process. The precipitation routes of TiC carbides influenced the behavior of hydrogen trapping and the co-precipitation of copper and TiC carbides significantly increased the hydrogen trapping capability of the steels. These heat treatments can therefore be used to tailor the resistance to hydrogen embrittlement in tempered martensitic steels. Importantly, co-precipitated TiC and e-copper particles in tempered martensitic steels show an enhanced capacity for hydrogen trapping and provide a range of trapping strengths. Co-precipitation is therefore proposed as a new prospect for designing steels with the capacity for substantial hydrogen trapping.

Currently, the selective activation of C(sp3)–F bonds and C–C bonds constitute one of the most widely used procedures for the synthesis of high-value products that range from pharmaceuticals to agrochemical applications. While numerous examples of these two methods have been reported in their respective fields, the processes which merge the activation of both single C(sp3)-F bonds and C–C bonds in one step still remain elusive. Here, we demonstrate the controllable defluoroalkylation–distal functionalization of trifluoromethylarenes with unactivated alkenes via distal heteroaryl migration. This is proposed to proceed via tandem C(sp3)–F and C–C bond cleavage using visible-light photoredox catalysis combined with Lewis acid activation. This strategy provides facile and flexible access to multiply functionalized α,α-difluorobenzylic ketones in useful yields (up to 88%) under mild conditions. The products can be further transformed into other valuable compounds, demonstrating the method’s utility. The radical C–F cleavage of fluoroalkanes offers a valuable method for the synthesis of fluorinated products. Here, photoredox catalysis promotes tandem intermolecular defluoroalkylation/intramolecular heteroaryl migration of unactivated alkenes to yield difluorobenzyl ketones, proposed to proceed via a radical mechanism.

Natural flavonoid formononetin (FN) has anticancer effects, but the hydrophobic structure, characteristics of the short half-life in vivo, limiting its clinical wide-ranging application. In this study, FN loaded Pluronic (PF)@folic acid (FA) micelles (FN-PF@FA), were prepared to improve the solubility, bioavailability and targeting. FA coupling PF was prepared by carbodiimide crosslinker chemical method, FN-PF@FA micelles were prepared by modified film hydration method, and compared the antitumor activity of FN loaded micelles with free FN In Vitro. The spherical smooth surface of FN-PF@FA micelles had smaller particle size (112.3±5.3 nm), high encapsulation efficiency (86.14±2.68%), high negative zeta potential (-25.8±0.57 mV), low critical concentration CMC (0.03 mg/mL), and better sustained release profile. In addition, FN-PF@FA micelles have a positive targeting effect on oral squamous cell carcinoma cells (SCC3). In 48 hours, the growth inhibition of 50% (GI50) was 28.6±1.2 μg/mL for FN and 17.4±0.78 μg/mL for FN-PF, the dose dropped by nearly 38.46%. In addition, the GI50 value of FN-PF@FA was 9.5±0.3 μg/mL, 66.43% lower than FN and 44.83% lower than FN-PF. Furthermore, the laser scanning confocal microscopy revealed that the conjugation of FA significantly improves the active targeting ability of micelles. FN-PF@FA micelles have the potential to target the release of anticancer drugs with higher bioavailability, further provides a new avenue for the application of traditional Chinese medicine extract in oral malignant tumor.

We report on an efficient solar-heat shield based on the highly transparent PEDOT:PSS thin film, which significantly reduces the temperature from 38.2 C to 33.5 C. To understand the superior solar-heat shielding ability, the modified PEDOT:PSS thin films were investigated by using the transmittance spectra, Raman scattering spectra, atomic-force microscopic (AFM) images and broadband refractive index spectra. The experimental results show that the molecular structure of the PEDOT chains can be manipulated by varying the Brownian motion of PEDOT polymers in the PEDOT:PSS solutions and the spin rate. The lower Brownian motion of PEDOT polymers and the higher spin rate both can change the molecular structure of the PEDOT chains from bended structures (de-doping states) to linear structures (doping states), which simultaneously increase the near-infrared absorption strength and the visible transparency due to the formation of bipolarons.