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Photocatalytic hydrogen (H2) evolution using covalent organic frameworks (COFs) is an attractive and promising avenue for exploration, but one of its big challenges is low photo-induced charge separation. In this study, we present a straightforward and facile dipole polarization engineering strategy to enhance charge separation efficiency, achieved through atomic modulation (O, S, and Se) of the COF monomer. Our findings demonstrate that incorporating atoms with varying electronegativities into the COF matrix significantly influences the local dipole moment, thereby affecting charge separation efficiency and photostability, which in turn affects the rates of photocatalytic H2evolution. As a result, the newly developed TMT-BO-COF, which contains highly electronegative O atoms, exhibits the lowest exciton binding energy, the highest efficiency in charge separation and transportation, and the longest lifetime of the active charges. This leads to an impressive average H2production rate of 23.7 mmol g−1h−1, which is 2.5 and 24.5 times higher than that of TMT-BS-COF (containing S atoms) and TMT-BSe-COF (containing Se atoms), respectively. A novel photocatalytic hydrogen evolution mechanism based on proton-coupled electron transfer on N in the structure of triazine rings in vinylene-linked COFs is proposed by theoretical calculations. Our findings provide new insights into the design of highly photoactive organic framework materials for H2evolution and beyond.

This study aimed to survey the geriatric nursing competencies of clinical nursing staff in Chongqing City, China, and provide suggestions to enhance these competencies.

In this work, a series of novel functionalized deep eutectic solvents (DESs) using 1,1,3,3-tetramethylguanidinium tetrazolate ([TMG][Tetz]) as a hydrogen-bond acceptor (HBA) and azole derivatives as hydrogen-bond donors (HBDs) were synthesized for the capture and catalytic reduction of SO2. [TMG][Tetz]:imidazole (Im) (1:2) DES with favorable stability and reversibility could effectively capture 2000 ppm of SO2. The absorption capacity of [TMG][Tetz]:Im (1:2) DES for 2000 ppm of SO2was high up to 2.0 mol SO2/mol DES (0.40 g SO2/g DES) at 293.15 K. The results of the UV–vis and FTIR spectra revealed that two kinds of combination existed between SO2and the DES: charge transfer interaction and chemical interaction. Surprisingly, the absorbed SO2, which was found to form charge transfer complexes with the DES, can be reduced by H2to elemental sulfur under mild conditions without byproduct and additional catalysts. The yield of elemental sulfur could reach up to 37% at 373.15 K.

The existing agricultural insecticides have developed drug resistance from long-term use. Isoxazoline derivatives are new insecticides discovered in the 21st century. Because of their unique insecticidal mechanism, high selectivity, safety, and no significant cross resistance with the existing pesticides on the market, they have become a hot spot in the field of pesticide research. Herein, a series of novel isoxazoline derivatives containing ether and oxime-ether structures were designed and synthesized by a scaffold-hopping strategy using the pesticide fluralaner as a template structure. Through the investigation of insecticidal activity and the systematic structure–activity relationship, a series of compounds with high insecticidal activities were found, and compounds I-4, II-9, and II-13with LC50values of 0.00008–0.00036 mg/L against diamondback moth emerged as novel insecticide candidates. These compounds also exhibited broad spectrum fungicidal activities against 14 plant fungi. The current work provides a reference for the design of new isoxazoline compounds based on the scaffold-hopping strategy.

This study aimed to determine the incidence of falls and risk factors associated with falling in discharged older adults.

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The asymmetric synthesis of (−)-chloramphenicol, (−)-azidamphenicol, and (+)-thiamphenicol and its (+)-3-floride, (+)-florfenicol, is reported. This approach toward the amphenicol antibiotic family features two key steps: (1) a cinchona alkaloid derived urea-catalyzed aldol reaction allows highly enantioselective access to oxazolidinone gem-diesters and (2) a continuous flow diastereoselective decarboxylation of thermally stable oxazolidinone gem-diesters to form the desired trans-oxazolidinone monoesters with two adjacent stereocenters that provide the desired privileged scaffolds of syn-vicinal amino alcohols in the amphenicol family.

Intrauterine adhesion (IUA) is a common cause of uterine infertility and one of the most severe clinical features is endometrial fibrosis namely endometrial scarring for which there are few cures currently. Blocked angiogenesis is the main pathological change in the scarred endometrium. The fibroblast growth factor 2 (bFGF), a member of FGF family, is usually applied to promote healing of refractory ulcer and contributes to angiogenesis of tissues. In this study, the sustained-release system of bFGF 100 µg was administrated around scarred endometrium guiding by ultrasound every 4 weeks in 18 patients (2–4 times). Results showed that after treatment, the menstrual blood volume, endometrial thickness and the scarred endometrial area were improved. Histological study showed blood vessel density increased obviously. Three patients (3/18) achieved pregnancy over 20 gestational weeks. Therefore, administrating the bFGF surrounding scarred endometrium may provide a new therapeutic approach for the patients with endometrial fibrosis.

In this study, we report the complete genome sequence of a ST65 hypervirulent Klebsiella pneumoniaeisolate carrying mcr-8from China. The aim was to investigate its molecular characteristics and resistant mechanism.

Objective To investigate BRCA1/2gene mutations and their relationship with clinicopathological features in patients with breast cancer in Zhoushan Islands.Methods High-throughput whole-exome gene sequencing was used to detect BRCA1/2mutations in 776 breast cancer patients in Zhoushan Islands.Results The BRCA1/2mutation rate of breast cancer patients in Zhoushan Islands was 4.38% (34/776). BRCA1mutations were significantly correlated with age, molecular type, and family history of breast and ovarian cancers. BRCA2mutations were most commonly found in invasive lobular carcinoma. Moreover, the BRCA2mutation rate of cancers with molecular type luminal B (receptor protein–tyrosine kinase [HER2]-negative) was also relatively high.Conclusion The rate of BRCA1/2mutations in breast cancer patients from Zhoushan Islands is approximately 4.38%, and BRCA1mutation is related to age, molecular type, and family history of breast and ovarian cancers.

Amorphous tilmicosin phosphate (TMP) suffers from low stability, and its crystalline product is not reported. At the same time, the gelation phenomenon often occurs in the crystallization process of TMP, which seriously affects the robustness of the process and product quality. In this paper, a crystal form of TMP was developed, and it was determined to be tilmicosin phosphate trihydrate by powder X-ray diffraction, thermogravimetric differential scanning calorimetry, Fourier transform infrared (FTIR), and Karl Fischer water content test. Besides, the gelation phenomenon and the gel transition process during TMP crystallization were studied by spectroscopic and microscopic methods. The results show that TMP gel is an intermediate form formed by amorphous TMP and solvent, and the type of solvents and water content in these solvents were important factors affecting the gelation and crystallization behavior of TMP. Finally, the TMP crystallization process was optimized, and trihydrate of TMP could be obtained directly without passing through the intermediate gel state. It was found that, after process optimization, the particle size, crystallinity, and stability of the obtained crystal products were improved.

This work reports the synthesis of a magnetic weak anionic spherical adsorbent with large size and starlike structure by magnetic induced self-assembly of organic latexes followed by modification with diethylaminoethyl hydrochloride (DEAE-HCl). The prepared adsorbent features unique starlike long chains stacked by anisotropic latexes (1 μm), large particle size (250 μm), and magnetic response. According to N2adsorption–desorption analysis, the starlike adsorbent possesses both specific surface area of 55.2 m2g–1and total mesopore volume of about 2.7 cm3g–1. After being modified with DEAE, the weak anionic adsorbent is evaluated for its adsorption performance. The analysis proves that the adsorbent approaches not only high static adsorption capacity of 113.05 mg mL–1for BSA adsorption but also fast adsorption rate for approaching the adsorption equilibrium within less than 40 min. Additionally, the large particle size and magnetic response of the adsorbent facilitate the easy recovery of adsorbent from aqueous solution by simple filtration and/or external magnetic force. Hence, the prepared magnetic starlike spherical adsorbent is expected to have potential application in high-performance and large-scale purification of proteins.

A Cp*Rh(III)/IL-based direct C-H bond cyanation system was developed for the first time. The system is a mild, efficient, and recyclable method for the synthesis of aryl nitriles. Many different directing groups can be used in this cyanation, and the reaction tolerates a variety of functional groups.

Janus hybrids, the anisotropic materials, have displayed very strong potentials in diverse research fields like life science and photology due to their unique properties. In this study, using graphene as an efficient nanoparticles (NPs) carrier, we present the fabrication of two-dimensional (2D) Janus hybrids (gold NPs/graphene) superstructures through a rapid, solventless sputtering method in 10-30 seconds. The micropores in graphene (~0.5 nm) is much smaller than the sputtered gold NPs, which can allow the sheet material to mesh gold NPs in one side to form a Janus structure. The size and morphology of gold NPs can be fine controlled on graphene by adjusting the sputtering current and time, while the resulting graphene hybrids enjoy tunable NPs area density and desirable thermal stability. The performance of hybrids has also been explored through standard electrochemical experiments.

Hydroxyapatite (HAP) nanocrystallites in all types of bones are distinguished by their ultrathin characteristics, which are uniaxially oriented with fibrillar collagen to uniquely expose the (100) faces. We speculate that living organisms prefer the specific crystal morphology and orientation of HAP because of the interactions between cells and crystals at the mineral–cell interface. Here, bone-like platy HAP (p-HAP) and two different rod-like HAPs were synthesized to investigate the ultrathin mineral modulating effect on cell bioactivity and bone generation. Cell viability and osteogenic differentiation of mesenchymal stem cells (MSCs) were significantly promoted by the platy HAP with (100) faces compared to rod-like HAPs with (001) faces as the dominant crystal orientation, which indicated that MSCs can recognize the crystal face and prefer the (100) HAP faces. This face-specific preference is dependent on the selective adsorption of fibronectin (FN), a plasma protein that plays a central role in cell adhesion, on the HAP surface. This selective adsorption is further confirmed by molecule dynamics (MD) simulation. Our results demonstrate that it is an intelligent choice for cells to use ultrathin HAP with a large (100) face as a basic building block in the hierarchical structure of bone, which is crucial to the promotion of MSCs osteoinductions during bone formation.

This paper establishes a high order condition on the restricted isometry property adapted to a frame D(D-RIP) for the signal recovery. It is shown that if the measurement matrix Asatisfies the D-RIP condition δtk 1, then all signals fwhich are sparse in terms of a tight frame D can be recovered stably or exactly via the l1-analysis model based on y = Af+ zin l2and Dantzig selector bounded noise setting.

In this paper, a sufficient condition is obtained to ensure the stable recovery (ɛ ≠ 0) or exact recovery (ɛ = 0) of all r-rank matrices X∈ ℝm×nfrom $$b = \mathcal{A}(X) + z$$via nonconvex Schatten p-minimization for any $$\delta _{4r} \in \left[ {\frac{{\sqrt 3 }} {2},1} \right)$$. Moreover, we determine the range of parameter pwith any given δ$$\delta _{4r} \in \left[ {\frac{{\sqrt 3 }} {2},1} \right)$$. In fact, for any given $$\delta _{4r} \in \left[ {\frac{{\sqrt 3 }} {2},1} \right)$$, p∈ (0, 2(1 − δ4r)] suffices for the stable recovery or exact recovery of all r-rank matrices.