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A transverse static magnetic field (TSMF) is implemented in a laboratory electroslag remelting (ESR) experiment to control eutectic carbides morphology of Cr8 die steel herein. Under action of a TSMF, the temperature distribution of the molten pool becomes homogeneous, the local solidification time is shortened, and the interdendritic region space shrinks, which result in an evenly spaced distribution of solute atoms and a reduction in interdendritic segregation. Therefore, the formation and subsequent growth of eutectic carbides are further inhibited, thereby causing the generation of smaller and more uniform distributed eutectic carbides due to the application of the TSMF. Moreover, the increase of the number of Al2O3–(Ti,V)N inclusions serves to be the heterogeneous nucleus of carbides (inclusions also become finer) caused by TSMF, which also contributes to the refinements of eutectic carbides in Cr8 ingots. [ABSTRACT FROM AUTHOR]

The cotton‐based metal–air batteries without any catalyst are constructed. Especially, the continuous electrolyte flowing depends on the capillary force and the gravity from the height difference between the inlet and outlet. The performance of the cotton‐based metal–air batteries under 2 mol L−1 NaOH or NaCl solutions is compared. The Al–air battery performance in the NaOH solution is better, while the Mg–air battery performance in the NaCl solution is the best. Considering the battery performance and cost, the alkaline cotton‐based Al–air battery is investigated for the subsequent experiments. The Al–air battery performance is evaluated under the different cotton cloth makeups, NaOH concentrations, height differences between the inlet and outlet. The results show that under the conditions of the cotton makeup (20 (warp) × 60 (yarn)), 4 mol L−1 NaOH and 60 mm height difference, the battery performance is optimal, with the peak power density of 12.33 ± 0.38 mW cm−2 and limiting current density of 35.28 ± 0.73 mA cm−2. To apply the cotton‐based Al–air battery, the two‐battery stack connected in series powers 15 light‐emitting diodes. The experiments demonstrate the cotton‐based Al–air battery without catalysts owns low cost and high power output, which has great potential as a micropower device. [ABSTRACT FROM AUTHOR]

Chronic wounds have become one of the major issues in medicine today, the treatments for which include dressing changes, negative pressure wound therapy, hyperbaric oxygen, light irradiation, surgery and so forth. Nevertheless, the application of diode lasers in chronic wounds has rarely been reported. This retrospective cohort study aimed to evaluate the therapeutic effect of diode laser (810 nm) irradiation on chronic wounds. Eighty‐nine patients were enrolled in the study. The control group (41 patients) received traditional dressing change therapy, while the diode laser treatment group (48 patients) were patients received additional treatment with diode laser (810 nm) irradiation for 10 min at each dressing change. Wound healing time was compared between two groups, while the pain relief index was creatively introduced to evaluate the effect of relieving wound pain, which was calculated by the difference in pain scores between the first and last dressing changes divided by the number of treatment days. The wound healing time of the diode laser treatment group was 22.71 ± 8.99 days, which was significantly shorter than that of the control group (37.44 ± 23.42 days). The pain relief index of the diode laser treatment group was 0.081 ± 0.055, which was significantly increased compared with that of the control group (0.057 ± 0.033). Our findings suggest that diode laser irradiation has the potential to promote healing in chronic wounds and relieve wound pain. [ABSTRACT FROM AUTHOR]

An axial static magnetic field (ASMF) is superimposed during the electroslag remelting (ESR) process to regulate the inclusion removal (GCr15 bearing steel) in the current study. After applying a 50 mT ASMF, the metal pool of the ESR ingot becomes shallower and the solidified dendritic structure tends to grow axially, together with a higher inclusion removal efficiency. The number of inclusions in ESR ingot decreases, and the inclusion with larger size (>10 μm) is almost eliminated. By tailoring the morphology of the liquid melt film (LMF), droplet, and metal pool, the ASMF applied in this study strengthens the kinetic conditions (inclusion migrated to slag/metal interface) for the inclusion removal, thus realizing the multi‐stage enhanced removal of inclusion during ESR process. [ABSTRACT FROM AUTHOR]

Idiopathic intracranial hypertension (IIH) is a disorder characterized by elevated intracranial pressure (ICP) that predominantly affects young obese women. IIH is a diagnosis of exclusion. That is, if increased ICP is suspected, magnetic resonance imaging and magnetic resonance venography of the brain are recommended to exclude secondary causes. Imaging findings, such as empty sella, orbital findings, meningocele, and encephalocele, are not diagnostic of ICP, nor does their absence exclude ICP either. Therefore, venous manometry is recommended as the gold standard for evaluation, regardless of previous anatomic imaging results. Venous manometry is an invasive examination that is frequently applied to derive physiologic information concerning the nature of the pressure gradient. However, the pathogenesis of IIH has not been fully elucidated. The presence of venous sinus stenosis in a subset of patients has provided some support for the potential mechanisms underlying this condition. Hence, this review provides an up‐to‐date discussion on the potential pathogenic mechanisms of IIH with a special focus on venous sinus stenosis. Level of Evidence: 1 Technical Efficacy Stage: 2 [ABSTRACT FROM AUTHOR]

BACKGROUND The objective of the study was to examine the expression profiles of mitochondrial proteins in at‐death and 24 h postmortem (PM) using tandem mass tag (TMT) approach to characterize the mitochondria possible mechanisms that are affiliated with tenderization. RESULTS: Results showed that the tender meat at 24 h PM emerged with more serious mitochondrial damage. Altogether 456 mitochondrial proteins were identified, including 442 down‐regulated and 14 up‐regulated proteins. These differentially‐expressed proteins were primarily involved in the progress of PM energy metabolism, apoptosis, and the morphological alterations of mitochondrial. Among them, 47 subunits (such as NDUFA2, COX4I1, and ATP5PB) were annotated into the oxidative phosphorylation pathway. VDAC1, VDAC2, and VDAC3 involving in the damage of MPTP, and IMMT, CHCHD3, APOL and APOO modulating the morphology of mitochondria, and DIABLO and AIFM1 released from mitochondria affect caspase's activation. HSPD1 and HSPE1 involved in apoptosis, mitochondrial physiological and morphological alterations. CONCLUSION: The earlier‐mentioned proteins were validated as potential indicators of tenderness regulated by mitochondrial damage. These results highlighted that mitochondrial damage possibly participate in PM tenderization of beef muscles by energy metabolism and cell apoptosis status. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Four mono‐ and two dinuclear Cu(I) complexes were synthesized based on novel 4‐diphenylphosphino‐benzimidazole (P^N) derivatives, and their structures as well as photophysical properties were systematically investigated. X‐ray crystallographic analysis reveals that the Cu(I) centers adopt pseudo‐tetrahedral geometries. All the complexes in powder at 293 K display bright phosphorescence with the highest photoluminescent quantum yield of 37.6 %. The emission maxima could be finely tuned from 514 to 592 nm by the methoxy substituent on the N^P ligands. The combined experimental results at different temperature (293 K and 77 K) and theoretical studies suggest that the nature of the emissive states can be mainly assigned as a dominant charge‐transfer character involving major components of 3(M+X) LCT transitions. [ABSTRACT FROM AUTHOR]

Three dinuclear copper(I) complexes (1, 2 and 3) of the form [(P N)Cu]2(μ2‐I)2 have been designed and synthesized with 4‐diphenylphosphino‐benzimidazole (P N) derivatives. X‐ray structural analysis shows that the complexes possess one rhombohedral Cu2I2 dimer that is coordinated with two P N ligands and exhibits a trans‐configuration. At 290 K, the copper complexes exhibit similar broad and featureless emission bands with peak maxima (λmax) at 585 nm, 565 nm and 586 nm, respectively. The temperature‐dependent photophysical behaviors accompanied with the theory calculations demonstrate that 1 represents a thermally activated delayed fluorescence behavior at ambient temperature, whereas luminescence of 2 and 3 is phosphorescence. Moreover, the complexes (1–3) achieve high photoluminescence quantum yields of 36.9 %, 43.0 % and 34.0 % with relatively short emission decay times of 5.85 μs, 7.99 μs and 5.99 μs, respectively. The solution‐processed organic light‐emitting diode based on 1 achieves a peak brightness of 3325 cd m−2 and an EQE of 2.99 %. [ABSTRACT FROM AUTHOR]

SUMMARY: The sugar status of a plant acts as a signal affecting growth and development. The phenomenon by which high levels of sugars inhibit seedling establishment has been widely used to gain insight into sugar‐signaling pathways. Natural allelic variation has been identified at the ANAC060 locus. The Arabidopsis Columbia ecotype produces a short ANAC060 protein without a transmembrane domain that is constitutively located to the nucleus, causing sugar insensitivity when overexpressed. In this study, we generated a genome‐wide DNA‐binding map of ANAC060 via chromatin immunoprecipitation sequencing using transgenic lines that express a functional ANAC060–GFP fusion protein in an anac060 background. A total of 3282 genes associated with ANAC060‐binding sites were identified. These genes were enriched in biotic and abiotic stress responses, and the G‐box binding motif was highly enriched in ANAC060‐bound genomic regions. Expression microarray analysis resulted in the identification of 8350 genes whose activities were altered in the anac060 mutant and upon sugar treatment. Cluster analysis revealed that ANAC060 attenuates sugar‐regulated gene expression. Direct target genes of ANAC060 included equivalent numbers of genes that were upregulated or downregulated by ANAC060. The various functions of these target genes indicate that ANAC060 has several functions. Our results demonstrate that ANAC060 directly binds to the promoter of ABI5 and represses the sugar‐induced transcription of ABI5. Genetic data indicate that ABI5 is epistatic to ANAC060 in both sugar and abscisic acid responses. [ABSTRACT FROM AUTHOR]

Summary: The phytohormone abscisic acid (ABA)‐induced leaf senescence facilitates nutrient reuse and potentially contributes to enhancing plant stress tolerance. However, excessive senescence causes serious reductions in crop yield, and the mechanism by which senescence is finely tuned at different levels is still insufficiently understood. Here, we found that the double mutant of core enzymes of the polycomb repressive complex 2 (PRC2) is hypersensitive to ABA in Arabidopsis thaliana. To elucidate the interplay between ABA and PRC2 at the genome level, we extensively profiled the transcriptomic and epigenomic changes triggered by ABA. We observed that H3K27me3 preferentially targets ABA‐induced senescence‐associated genes (SAGs). In the double, but not single, mutant of PRC2 enzymes, these SAGs were derepressed and could be more highly induced by ABA compared with the wild‐type, suggesting a redundant role for the PRC2 enzymes in negatively regulating ABA‐induced senescence. Contrary to the rapid transcriptomic changes triggered by ABA, the reduction of H3K27me3 at these SAGs falls far behind the induction of their expression, indicating that PRC2‐mediated H3K27me3 contributed to long‐term damping of ABA‐induced senescence to prevent an oversensitive response. The findings of this study may serve as a paradigm for a global understanding of the interplay between the rapid effects of a phytohormone such as ABA and the long‐term effects of the epigenetic machinery in regulating plant senescence processes and environmental responses. Significance Statement: The present study revealed the interplay between the rapid effect of the phytohormone abscisic acid and the long‐term effect of epigenetic machinery polycomb repressive complex 2 in regulating plant senescence process. [ABSTRACT FROM AUTHOR]

Abstract: In this article, mechanisms of phosphine‐catalyzed [4 + 3] annulation of allenoates with C, N‐cyclic azomethine imines have been investigated using density functional theory. The catalytic cycle for the title reaction consists of five steps. Namely, the first step is the nucleophilic addition of phosphine catalyst, the second one is the CC bond formation, the third one is the proton transfer process, and the next one is the ring‐closure process, the last one is dissociation of the catalyst and the product generation. The calculated results indicate that the nucleophilic addition of phosphine catalyst is rate‐determining. With the use of Cat as the chiral catalyst, optically active products were obtained in good yields with excellent enantioselectivities while the CC bond formation is stereoselectivity‐determining. Furthermore, the theoretically predicted the main product is SS configuration, which is in good agreement with the experimental results. The special role of the catalysts and origin of stereoselectivity was also identified by NBO, GRI, and FMO analyses. This work might be helpful for understanding the significant roles of phosphine catalyst and thus provide valuable insights on the rational design of potential catalysts for this kind of reactions. [ABSTRACT FROM AUTHOR]

The zinc complex ZnE containing two 2-(2'-hydroxyphenyl)-1-ethyl-4-hydroxybenzimidazole (EtL) ligands has been designed and synthesized. The zinc ion acts as a spacer linking the two coordinated EtL, between which intramolecular hydrogen bonds form. Upon excitation, in addition to a weak emission at 399 nm, ZnE exhibits strong excited-state intramolecular proton-transfer (ESIPT) emission with a maximum at 479 nm with a large Stokes shift (8449 cm-1) in tetrahydrofuran solution. Importantly, the ESIPT in ZnE also takes place in the powder form, resulting in dual emission (407 and 490 nm) with total photoluminescence quantum yields (Φ) of 0.16. The results of quantum calculations suggest that the ESIPT fluorescence is based on a zwitterionic excited-state species resulting from a single proton transfer between the ligands. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations of crystals can enlighten interpretation of experimental X-ray crystallography data and elucidate structural dynamics and heterogeneity in biomolecular crystals. Furthermore, because of the direct comparison against experimental data, they can inform assessment of molecular dynamics methods and force fields. We present microsecond scale results for triclinic hen egg-white lysozyme in a supercell consisting of 12 independent unit cells using four contemporary force fields (Amber ff99SB, ff14ipq, ff14SB, and CHARMM 36) in crystalline and solvated states (for ff14SB only). We find the crystal simulations consistent across multiple runs of the same force field and robust to various solvent equilibration schemes. However, convergence is slow compared with solvent simulations. All the tested force fields reproduce experimental structural and dynamic properties well, but Amber ff14SB maintains structure and reproduces fluctuations closest to the experimental model: its average backbone structure differs from the deposited structure by 0.37Å ; by contrast, the average backbone structure in solution differs from the deposited by 0.65Å . All the simulations are affected by a small progressive deterioration of the crystal lattice, presumably due to imperfect modeling of hydrogen bonding and other crystal contact interactions; this artifact is smallest in ff14SB, with average lattice positions deviating by 0.20Å from ideal. Side-chain disorder is surprisingly low with fewer than 30% of the nonglycine or alanine residues exhibiting significantly populated alternate rotamers. Our results provide helpful insight into the methodology of biomolecular crystal simulations and indicate directions for future work to obtain more accurate energy models for molecular dynamics. [ABSTRACT FROM AUTHOR]

First-principles calculations are performed to investigate the elastic anisotropy, and thermodynamic properties of chromium tetraboride (CrB4) under extreme P- T conditions. The calculated equilibrium lattice and the normalized crystal parameters as a function of pressure are in good agreement with the available experimental and theoretical data. Elastic constants Cij are calculated in the pressure range of 0-50 GPa, and the bulk modulus B, shear modulus G, and Young's modulus E are also obtained according to the Voigt-Reuss-Hill (VRH) approximation. Anisotropic indexes are employed to characterize the mechanical anisotropy. The bulk modulus and Young's modulus as a function of crystal orientations are also investigated. The obtained results suggest that CrB4 exhibits a pronounced elastic anisotropy. It is strongest along the b-axis in response to compression loading, and the {100} and {001} shear planes might be the cleavage planes. The elastic anisotropy of CrB4 may possibly limit its applications. Using the quasiharmonic Debye model, thermodynamic properties like Debye temperature, Grüneisen parameter, heat capacity, and expansion coefficient are also systematically explored under extreme P- T conditions. [ABSTRACT FROM AUTHOR]

We study the initial boundary value problem of a class of fourth order semilinear parabolic equations. Global existence and nonexistence of solutions with initial data in the potential well are derived. Moreover, by using the iteration technique for regularity estimates, we obtain that for any k ≥ 0, the semilinear parabolic possesses a global attractor in H k(Ω), which attracts any bounded subsets of H k(Ω) in the H k-norm. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new reactivity pattern of α-aminoalkyl radicals, involving nucleophilic attack on CN triple bonds under thermal conditions, has been developed to construct α-amino nitriles. In contrast to previous CH functionalization of tertiary amines involving α-aminoalkyl radicals, this methodology does not require the use of photocatalytic conditions or a transition-metal catalyst. Inexpensive and nontoxic phenylacetonitrile was chosen as cyano source for this α-aminonitrile forming reaction. A plausible mechanism is proposed based upon experimental and computational results. An α-aminoalkyl radical intermediate and benzoyl cyanide have been shown to be key intermediates in this green and mild radical process. Nucleophilic attack of the α-aminoalkyl radical on the CN bond of PhCOCN followed by an elimination step forms the desired α-aminonitrile and an acyl radical. [ABSTRACT FROM AUTHOR]

The chalcone synthase (CHS) superfamily of type III polyketide synthases (PKSs) generate the backbones of a variety of plant secondary metabolites. An active bifunctional chalcone synthase/benzalacetone synthase (CHS/BAS) from Polygonum cuspidatum was overexpressed in Escherichia coli as a C-terminally polyhistidine-tagged fusion protein, purified to homogeneity and crystallized using polyethylene glycol 4000 as a precipitant. The production of well shaped crystals of the complex between PcPKS1 and benzalacetone was dependent on the presence of sorbitol and barium chloride as additives. The crystals belonged to the orthorhombic space group P212121, with unit-cell parameters a = 80.23, b = 81.01, c = 122.89 Å, and diffracted X-rays to at least 2.0 Å resolution. [ABSTRACT FROM AUTHOR]

Chemoresistance is a major cause of treatment failure in ovarian cancer. Therefore, it is necessary to explore alternative therapeutic methods to overcome drug resistance for ovarian cancer treatment. We previously reported that programmed cell death 4 (PDCD4), a tumor suppressor, significantly suppresses the malignant phenotype of ovarian cancer cells and its lost or low expression in ovarian cancer is associated with unfavorable prognosis of patients. Here we show that PDCD4 improves the sensitivity of ovarian cancer cells to platinum-based chemotherapy. Overexpression of PDCD4 enhanced chemosensitivity in SKOV3 and CAOV3 cells with low levels of PDCD4, whereas knockdown of PDCD4 reduced chemosensitivity in OVCAR3 cells with high levels of PDCD4. Subsequently, the combination of enforced PDCD4 expression with cisplatin treatment significantly suppressed ovarian tumor growth in a xenograft animal model. The PDCD4 effect appears to be specific for cisplatin and carboplatin, not affecting cyclophosphamide, etoposide, or paclitaxel. Mechanistically, PDCD4 significantly increased cisplatin-induced cleavage of caspase-3 and caspase-8, but had only a slight impact on caspase-9 cleavage and the expression of Bax and Bcl-2 in vitro and in vivo. A specific caspase-8 inhibitor, Z-ITED-FMK, attenuated cisplatin-induced apoptosis in PDCD4-overexpressing ovarian cancer cells. Taken together, our results indicate that PDCD4 enhances cisplatin-induced apoptosis by mainly activating the death receptor pathway, and PDCD4 gene transfer in combination with cisplatin therapy may break the resistance of ovarian cancer cells to chemotherapy. ( Cancer Sci 2010) [ABSTRACT FROM AUTHOR]

The chemo- and stereoselective title reaction proceeds under mild conditions and has a broad substrate scope. [ABSTRACT FROM AUTHOR]

This new multicomponent radical reaction involves a cleavage of two C-F bonds and one C-X bond and three new bonds (C=O, C=C, and C-N) are created. [ABSTRACT FROM AUTHOR]

In contrast to established C-H functionalizations of tertiary amines involving α-aminoalkyl radicals the present method does not require photocatalytic conditions or a transition-metal catalyst.An α-aminoalkyl radical and benzoyl cyanide are the key intermediates in this process. [ABSTRACT FROM AUTHOR]