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The innovation of synthetic strategies for selective B–H functionalization is a pivotal objective in the realm of boron cluster chemistry. However, the precise, efficient, and rapid functionalization of a B–H bond of carboranes that is distant from the existing functional groups remains intractable owing to the limited approaches for site-selective control from the established methods. Herein, we report a dative bonding activation strategy for the selective functionalization of a nonclassical remote B–H site of nido-carboranes. By leveraging the electronic effects brought by the exopolyhedral B(9)-dative bond, a cross-nucleophile B–H/S–H coupling protocol of the distal B(5)–H bond has been established. The dative bond not only amplifies the subtle reactivity difference among B–H bonds but also significantly changes the reactive sites, further infusing nido-carboranes with additional structural diversity. This reaction paradigm features mild conditions, rapid conversion, efficient production, broad scope, and excellent group tolerance, thus enabling the applicability to an array of complex bioactive molecules. The efficient and scalable reaction platform is amenable to the modular construction of photofunctional molecules and boron delivery agents for boron neutron capture therapy. This work not only provides an unprecedented solution for the selective diversification of distal B–H sites in nido-carboranes but also holds the potential for expediting the discovery of novel carborane-based functional molecules.

To prepare anion exchange membranes with high water electrolysis and single fuel cell performance, an inorganic–organic composite (IOC) strategy with click cross-linked membranes coated with different contents of hydrophilic polar nanozirconia is proposed to fabricate composite membranes (CM) PBP-SH-Zrx. The performance test results showed that the CM PBP-SH-Zr4 not only has good through-plane ionic conductivity (167.7 mS cm–1, 80 °C), but also exhibits satisfactory dimensional stability (SR 16.5%, WU 206.4%, 80 °C), especially demonstrating excellent alkaline stability with only 16% degradation (2 M NaOH for 2200 h). In water electrolysis, the “microgap” between the membrane and catalyst layer (solid–solid interface) is alleviated, and the membrane electrode assembly (MEA) interfacial compatibility (liquid–solid–solid interface) is enhanced. The CM PBP-SH-Zr4 showed the lowest charge transfer resistance (Rct, 0.037 Ω cm2) and a high current density of 2.5 A cm–2at 2.2 V, while the voltage drop was 0.361 mV h–1after 360 h of endurance (six start–stop cycles) at 60 °C and 500 mA cm–2, proving a good water electrolysis durability. Moreover, an acceptable peak power density of 0.464 W cm–2at 80 °C is achieved in a H2/O2fuel cell with a PBP-SH-Zr4-AEM. Therefore, the IOC strategy can enhance the membrane’s comprehensive performance and interface compatibility of MEA and may promote the development of anion exchange membranes (AEMs) for water electrolysis and fuel cells.

In order to improve the mechanical and water electrolysis performance of anion exchange membranes (AEMs), we adjusted the ratio between p-terphenyl and m-terphenyl to balance the backbone conformation, which gives it a better suitability for a better combination with cations. The results showed that poly(m-terphenyl-co-p-terphenyl)-based AEMs have excellent mechanical properties. Among them, the m-p-TP-40-BOP-ASU membrane has the highest tensile strength and elongation at break (75.72 MPa and 16.07%). The ionic conductivity reaches 137.14 mS cm–1at 80 °C owing to the fact that efficient ion-conducting channels are formed by well-balanced molecular structures. The current density of the m-p-TP-40-BOP-ASU membrane reached 1.96 A cm–2(1 M KOH aq, 2.0 V and 60 °C). After testing for 112 h under a current density of 500 mA cm–2, the voltage increased by 102 mV compared to the initial electrolysis voltage. All results have shown that m-p-TP-x-BOP-ASU has excellent electrolysis performance and electrochemical durability and has a promising application prospect in AEM water electrolyzers.

The efficient and selective functionalization of icosahedral carboranes (C2B10H12) at the boron vertexes is a long-standing challenge owing to the presence of 10 inert B–H bonds in a similar chemical environment. Herein, we report a new reaction paradigm for direct B–H functionalization of icosahedral carboranes viaB–H homolysis enabled by a nitrogen-centered radical-mediated hydrogen atom transfer (HAT) strategy. Both the HAT process of the carborane B–H bond and the resulting boron-centered carboranyl radical intermediate have been confirmed experimentally. The reaction occurs at the most electron-rich boron vertex with the lowest B–H bond dissociation energy (BDE). Using this strategy, diverse carborane derivatization, including thiolation, selenation, alkynylation, alkenylation, cyanation, and halogenation, have been achieved in satisfactory yields under a photoinitiated condition in a metal-free and redox-neutral fashion. Moreover, the synthetic utility of the current protocol was also demonstrated by both the scale-up reaction and the construction of carborane-based functional molecules. Therefore, this methodology opens a radical pathway to carborane functionalization, which is distinct from the B–H heterolytic mechanism in the traditional strategies.

Purpose: Most differentiated thyroid cancer (DTC) patients have a good prognosis after surgery, but radioiodine refractory differentiated thyroid cancer (RAIR-DTC) patients have a significantly reduced 5-year survival rate (<60%) and a significantly increased recurrence rate (>30%). This study aimed to clarify the tescalcin (TESC) role in promoting the malignant PTC progression and providing a potential target for RAIR-DTC treatment. Methods: We analyzed TESC expression and clinicopathological characteristics using the Cancer Genome Atlas (TCGA) and performed qRT-PCR on tissue samples. TPC-1 and IHH-4 proliferation, migration, and invasion were detected after transfection with TESC-RNAi. Using Western blot (WB), several EMT-related indicators were detected. Moreover, iodine uptake of TPC-1 and IHH-4 after transfection with TESC-RNAi was detected. Finally, NIS, ERK1/2, and p-ERK1/2 levels were determined by WB. Results: TESC was significantly upregulated in DTC tissues and positively correlated with BRAF V600E mutation based on data analysis from TCGA and our center. Reduced expression of TESC in both IHH-4 (BRAF V600E mutation) and TPC-1 (BRAF V600E wild type) cells significantly inhibited cell proliferation, migration, and invasion. It downregulated the EMT pathway markers Vimentin and N-cadherin, and increased E- cadherin. Moreover, TESC knockdown significantly inhibited ERK1/2 phosphorylation and decreased NIS expression in DTC cells, with a remarkably increased iodine uptake rate. Conclusions: TESC was highly expressed in DTC tissues and may have promoted metastasis through EMT and induced iodine resistance by downregulating NIS in DTC cells.

Papillary thyroid carcinoma (PTC) and papillary thyroid microcarcinoma (PTMC) are generally characterized as less invasive forms of thyroid cancer with favorable prognosis. However, once lateral cervical lymph node metastasis takes place, the prognosis may be significantly impacted. The purpose of this study was to evaluate whether there is a difference in the pattern of lateral lymph node metastasis between PTC and PTMC. A retrospective analysis was performed for PTC and PTMC patients that underwent central area dissection and unilateral lateral neck lymph node dissection (II–V area) between January 2020 and December 2021. Compared with PTMC group, the PTC group exhibited higher incidence of capsule invasion, extrathyroid invasion and lymphatic vessel invasion. Both the number and rate of central lymph nodes metastasis were elevated in the PTC group. While the number of lateral cervical lymph node metastasis was higher, the metastasis rate did not demonstrate significant difference. No significant differences were identified in the lymph node metastasis patterns between the 2 groups. The determination of the extent of lateral neck lymph node dissection solely based on the tumor size may be unreliable, as PTC and PTMC showed no difference in the number and pattern of lateral neck metastasis. Additional clinical data are warranted to reinforce this conclusion. For patients categorized as unilateral, bilateral, or contralateral cervical lymph node metastasis (including level I, II, III, IV, or V) or retropharyngeal lymph node metastasis who require unilateral lateral neck dissection, the size of the primary tumor may not need to be a central consideration when assessing and deciding the extent of lateral neck dissection.

Aim:To evaluate whether chelerythrine (CHT) exhibited antifungal activity against Candida albicans in vitroand in vivoand to explore the underlying mechanisms. Materials & methods:Broth microdilution assay and Galleria mellonellamodel were used to evaluate the antifungal effect in vitroand in vivo, respectively. Mechanism studies were investigated by morphogenesis observation, Fluo-3/AM, DCFH-DA and rhodamine6G assay, respectively. Results:CHT exhibited antifungal activity against C. albicansand preformed biofilms with minimum inhibitory concentrations ranged from 2 to 16 μg/ml. Besides, CHT protected G. mellonellalarvae infected by C. albicans. Mechanisms studies revealed that CHT inhibited hyphal growth, increased intracellular calcium concentration, induced accumulation of reactive oxygen species and inhibited drug transporter activity. Conclusion:CHT exhibited antifungal activity against C. albicans.

Detection accuracy is an important performance indicator of ground-based telescopes and is affected mainly by pointing error, geometric distortion of the optical system, and parameter errors caused by machining error and installation error. To improve detection accuracy, a modified algorithm based on a simulated annealing algorithm is proposed in this paper; this algorithm is able to correct pointing, derive a geometric distortion solution, and re-estimate some parameters of telescopes simultaneously. The efficiency of the proposed method is verified by using the observation data of the telescope, whose aperture is 600 mm under two distortion models (the physical model and polynomial fitting model). The results show that the method presented in this paper can effectively solve the problem of nonconvergence of the distortion solution with a pointing error. The final angle error under the polynomial fitting model is 1.07″, and the pixel error is 0.06 pixels; the errors under the physical model are 1.08″ and 0.07 pixels. The correction effect under the two distortion models is basically the same, but the averaged operation speed based on the physical model is 19.45% faster.

Zr 61.7 Al 8 Ni 13 Cu 17 Sn 0.3 bulk metallic glass samples with different aspect ratios in the range of 0.25–2.25 were deformed by compression, and the effect of aspect ratio on the evolution of shear bands was investigated. It is found that for the deformed Zr 61.7 Al 8 Ni 13 Cu 17 Sn 0.3 bulk metallic glass, the average shear band spacing decreases and the shear band density increases monotonically as the aspect ratio increases from 0.25 to 2.25. A minimal average shear band spacing of 0.478 µm is achieved for the sample with an aspect ratio of 2.25. In addition, the fractions of shear bands with spacings below 100 and 50 nm are about 12.84% and 6.76%, respectively, for the sample with an aspect ratio of 2.25. The reason for the formation of a higher density of shear bands can probably be attributed to the increase of the driving force for the sample with a larger aspect ratio. [ABSTRACT FROM AUTHOR]

The present paper studied the chitosan-doped composite diaphragm by the phase exchange method with the objective of developing a composite diaphragm that complies with the alkaline water electrolysis requirements, as well as tested the electrolytic performance of the diaphragm in alkaline water electrolysis. The structure and morphology are characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The performance of chitosan-doped composite diaphragms was tested; CS3Z12composite diaphragm with a low area resistance (0.20 Ω cm2), a high bubble point pressure (2.75 bar), and excellent electrochemical performance (current density of 650 mA cm–2at 1.83 V) shows the best performance. Moreover, the performance of the synthesized composite diaphragm is significantly elevated compared to commercial diaphragms (Zirfon PERL), which is promising for practical application in alkaline electrolytic cells.

Sodium hypochlorite (NaClO) is an important chlorine-based disinfectant that has been widely used for disinfection in public places and domestic environments. In the present work, we have designed a novel electrolyzer for NaCl electrolysis to produce high-quality NaClO. The cell was separated into two chambers by a bipolar membrane. Thus, NaCl electrooxidation can be conducted in a basic anolyte, and H2O electroreduction can be conducted in an acidic catholyte. Consequently, higher efficiency can be achieved than that of conventional methods. After 3 h of electrolysis, the available chlorine reached 531.8 mg/L with no deformation of the bipolar membrane. This electrolyzer provides a new avenue to produce high-quality NaClO from NaCl electrolysis.

Rhus chinensisis a well-known Chinese medicinal plant and chalcone synthase (CHS) is a key enzyme involved in flavonoid biosynthesis. In this paper, both the cDNA and the genomic sequence encoding CHS from R. chinensiswere cloned and anaylzed. The ORF of RcCHS was 1,173 bp in size and predicted to encode a 390-amino acid polypeptide. Phylogenetic analysis showed that RcCHS was grouped into a branch with legume plants Glycine maxand Medicago sativa. Real-time quantitative PCR showed that RcCHS gene expression were clearly tissue-specific, but not correlated with total anthocyanins accumulation as previously reported in some other plants. Moreover RcCHS was highly expressed in E.coliwith pGEX-6P-1 vector, which will be helpful for further research on the structure, cellular localization and catalytic mechanisms of RcCHS.