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Sorbitol was employed as the grafting agent to modify nano-silica by the hyperbranched reaction. The obtained carrier was further used to prepare immobilized 4-dimethylaminopyridine (DMAP), which was successfully applied to produce vitamin E succinate. Two crucial steps were systematically investigated during the preparation of hyperbranched loadedDMAP: the epoxy-alcohol addition and N-alkylation reactions. For the epoxy-alcohol addition reaction, the maximum hydroxyl content reached 8.89 mmol/g when the molar ratio of sorbitol to epoxide was 2.5:1, the reaction temperature was 55 °C, the stirring ratewas 500 rpm, and the reaction timewas 8 h. In theN-alkylation reaction, when the reaction timewas 20 h, the reaction temperature was 130 °C, the molar ratio of MAP to K2CO3 was 1:1.5, the KI to MAP molar ratio was 1:1 and the stirring rate was 600 rpm, the highest loading of DMAP reached 5.17mmol/g. The catalytic performance of the loaded DMAP with different branching levels was evaluated by the acetylation reaction. The highest catalytic activity was observed in the hyperbranched catalyst, which reached 24.97 mmol/h·g. Moreover, the stability of the prepared immobilizedDMAPwas significantly enhanced. After being used for ten batches, 94.9% of the catalytic activity retention rate was obtained. [ABSTRACT FROM AUTHOR]

A TOPSIS evaluation index system of entropy weight of enterprise internal control quality based on fuzzy matter-element model was established to master the enterprise internal control quality comprehensively and analyze its influences on enterprise innovation performance accurately. Firstly, a composite fuzzy matter-element model was established based on the fuzzy matter-element theory. Secondly, weights of evaluation indexes were determined by the entropy weight method. Thirdly, the concept of relative closeness was developed by comparison with positive and negative ideal indexes. Finally, the internal control quality levels of 781 listed companies in Chin were measured by TOPSIS method. Results show that: weights of five level-1 indexes for enterprise internal control quality evaluation are different. Specifically, weights of Law & Regulation, Operation and Strategy are higher than those of Financial Statements and Assets Safety. In the level-2 index system, weights of “major litigation and arbitration cases”, “turnover of total assets” and “Tobin’s Q” occupy 66% of total weights. Listed companies which occupy the top10 position in term of internal control quality mainly belong to industries requiring strict monitoring and control over safety production. Enterprise internal control quality differs significantly among different industries. Research conclusions can provide methods and practical references to evaluate internal control quality of Chinese enterprises. [ABSTRACT FROM AUTHOR]

Dust contamination to ventilation systems is a common issue for mine operators during underground coal mining. In the present study, dust dispersion driven by a hybrid ventilation system in an underground mine has been investigated via a computational fluid dynamics (CFD) model. Specifically, the numerical model was developed based on the Euler-Lagrange method where the trajectory of dispersed dusts was solved individually. Dust dispersion induced by turbulence was considered by a stochastic tracking model. Effects of key parameters (e.g., gas velocity and exhaust duct length) on dust dispersion characteristics throughout the coal roadway have been examined. The results showed that the distribution of dusts exhibited extreme non-uniformity with a significantly higher concentration present near the mining face, particularly on the exhaust side. The cross-sectional average dust concentration substantially decreased along the axial direction in the front part of the coal roadway. Intense circumfluence and secondary sedimentation of dusts were found to be the main mechanisms that drove the non-uniform distribution of dusts. The model is shown to be capable of reproducing the dust dispersion process captured in the experiments and the prediction results agree well with the experimental data. [ABSTRACT FROM AUTHOR]

Phospholipase C (Plc1p) in Saccharomyces cerevisiae is required for normal degradation of repressor Mth1p and expression of the HXT genes encoding cell membrane transporters of glucose. Plc1p is also required for normal localization of glucose transporters to the cell membrane. Consequently, plc1Δ cells display histone hypoacetylation and transcriptional defects due to reduced uptake and metabolism of glucose to acetyl-CoA, a substrate for histone acetyltransferases. In the presence of glucose, Mth1p is phosphorylated by casein kinase I Yck1/2p, ubiquitinated by the SCFGrr1 complex and degraded by the proteasome. Here, we show that while Plc1p does not affect the function of the SCFGrr1 complex or the proteasome, it is required for normal protein level of Yck2p. Since stability of Yck1/2p is regulated by a glucose-dependent mechanism, PLC1 inactivation results in destabilization of Yck1/2p and defect in Mth1p degradation. Based on our results and published data, we propose a model in which plc1Δ mutation causes increased internalization of glucose transporters, decreased transport of glucose into the cells, and consequently decreased stability of Yck1/2p, increased stability of Mth1p and decreased expression of the HXT genes. [ABSTRACT FROM AUTHOR]

Regulation of mitochondrial biogenesis and respiration is a complex process that involves several signaling pathways and transcription factors as well as communication between the nuclear and mitochondrial genomes. Under aerobic conditions, the budding yeast Saccharomyces cerevisiae metabolizes glucose predominantly by glycolysis and fermentation. We have recently shown that altered chromatin structure in yeast induces respiration by a mechanism that requires transport and metabolism of pyruvate in mitochondria. However, how pyruvate controls the transcriptional responses underlying the metabolic switch from fermentation to respiration is unknown. Here, we report that this pyruvate effect involves heme. We found that heme induces transcription of HAP4, the transcriptional activation subunit of the Hap2/3/4/5p complex, required for growth on nonfermentable carbon sources, in a Hap1p- and Hap2/3/4/5p-dependent manner. Increasing cellular heme levels by inactivating ROX1, which encodes a repressor of many hypoxic genes, or by overexpressing HEM3 or HEM12 induced respiration and elevated ATP levels. Increased heme synthesis, even under conditions of glucose repression, activated Hap1p and the Hap2/3/4/5p complex and induced transcription of HAP4 and genes required for the tricarboxylic acid (TCA) cycle, electron transport chain, and oxidative phosphorylation, leading to a switch from fermentation to respiration. Conversely, inhibiting metabolic flux into the TCA cycle reduced cellular heme levels and HAP4 transcription. Together, our results indicate that the glucose-mediated repression of respiration in budding yeast is at least partly due to the low cellular heme level. [ABSTRACT FROM AUTHOR]

On treatment with Pd(OAc)2 and K2CO3, a variety of 3-aryl-2-(2-bromoallyl)-1,3-dicarbonyl compounds went through a monodearoylative dimerization reaction to provide polysubstituted [3]dendralenes in moderate to good isolated yields. [ABSTRACT FROM AUTHOR]

A crystal plasticity finite-element model, which explicitly and directly represents the complex microstructures of a non-metallic agglomerate inclusion within polycrystal nickel alloy, has been developed to study the mechanistic basis of fatigue crack nucleation. The methodology is to use the crystal plasticity model in conjunction with direct measurement at the microscale using high (angular) resolution-electron backscatter diffraction (HREBSD) and high (spatial) resolution-digital image correlation (HR-DIC) strain measurement techniques. Experimentally, this sample has been subjected to heat treatment leading to the establishment of residual (elastic) strains local to the agglomerate and subsequently loaded under conditions of low cyclic fatigue. The full thermal and mechanical loading history was reproduced within the model. HR-EBSD and HR-DIC elastic and total strain measurements demonstrate qualitative and quantitative agreement with crystal plasticity results. Crack nucleation by interfacial decohesion at the nickel matrix/agglomerate inclusion boundaries is observed experimentally, and systematic modelling studies enable the mechanistic basis of the nucleation to be established. A number of fatigue crack nucleation indicators are also assessed against the experimental results. Decohesion was found to be driven by interface tensile normal stress alone, and the interfacial strength was determined to be in the range of 1270-1480 MPa. [ABSTRACT FROM AUTHOR]

Regulation of mitochondrial biogenesis and respiration is a complex process that involves several signaling pathways and transcription factors as well as communication between the nuclear and mitochondrial genomes. Here we show that decreased expression of histones or a defect in nucleosome assembly in the yeast Saccharomyces cerevisiae results in increased mitochondrial DNA (mtDNA) copy numbers, oxygen consumption, ATP synthesis, and expression of genes encoding enzymes of the tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OXPHOS). The metabolic shift from fermentation to respiration induced by altered chromatin structure is associated with the induction of the retrograde (RTG) pathway and requires the activity of the Hap2/3/4/5p complex as well as the transport and metabolism of pyruvate in mitochondria. Together, our data indicate that altered chromatin structure relieves glucose repression of mitochondrial respiration by inducing transcription of the TCA cycle and OXPHOS genes carried by both nuclear and mitochondrial DNA. [ABSTRACT FROM AUTHOR]

Context: The use of traditional chinese medicine (TCM) for breast cancer patients inhibits tumor cell growth and proliferation, alleviates adverse reactions, and inhibits tumor recurrence and metastasis post-surgery. An assessment of its historical efficacy and an examination of the latest research trends are imperative to thoroughly leverage the potential of TCM for breast cancer treatment. Objective: this study analyzes the published literature on TCM for breast cancer treatment using bibliometric analysis to determine the current state, identify hot spots, and discern trends, providing insight into research in this field. Methods: TCM-based breast cancer treatment publications between 2003 and 2022 were retrieved from the web of Science, china National Knowledge infrastructure, wanfang, and Duxiu databases. Visual analysis was performed using VOSviewer (V1.6.19) and citeSpace (V6.3.R1) software. examined metrics included the annual publication count, literature and journal, national and institutional contributions, author co-occurrence, keyword co-occurrence, keywords timeline, and keywords with citation bursts in this research field. Results and conclusion: A total of 1080 english publications and 2617 chinese publications were included in the analysis. china was the leading contributor of publications. High-frequency keywords such as 'apoptosis', 'expression', 'in vivo', 'chemotherapy', 'triple-negative breast cancer', and 'lymphedema' were identified from english and chinese publications; 'epithelial mesenchymal transition' and 'network pharmacology' emerged as hotspots. the development of modern science, technology, and in-depth research can result in broader prospects for the research and application of TCM in breast cancer treatment, resulting in more effective solutions for the treatment of breast cancer and other malignant tumors. [ABSTRACT FROM AUTHOR]

Detection of small molecules or proteins of living cells provides an exceptional opportunity to study genetic variations and functions, cellular behaviors, and various diseases including cancer and microbial infections. Our aim in this review is to give an overview of selected research activities related to nucleic acid-based aptamer techniques that have been reported in the past two decades. Limitations of aptamers and possible approaches to overcome these limitations are also discussed. [ABSTRACT FROM AUTHOR]

Two new compounds, fumitremorgin 12-methoxy-13-[5'-hydroxy-2'-(1''- hydroxy-3''-methoxy-5''-methylbenzoyl)-3'-methoxy]benzoic acid methyl ester (fumitremorgin D, 1) and 4,8,10,14-tetramethyl-6-acetoxy-14-[16-acetoxy-19-(20,21- dimethyl)-18-ene]-phenanthrene-1-ene-3,7-dione (2) were isolated from the cultured endophytic isolated fungus Aspergillus fumigatus, together with fourteen known compounds. Their structures were elucidated by 1-D and 2-D NMR analyses. The cytotoxicity profile of the compound against the human hepatocellular carcinoma cell line HepG2 was evaluated by MTT antiproliferative assays. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals, as well as hydroxypropyl cellulose, can form lyotropic liquid crystals, which can be processed into pigments or glitter products for sustainable coloration. Some stimuli-responsive polymers or nanoparticles are expected to form colorimetric sensors via co-assembly with these cellulosic photonic crystals. The co-assembly behavior of CNCs with polymers is determined by the hydrogen bonds and physical adsorption. Thus, adjusting the molecular chain structure, hydrophilicity, and electrostatic interaction of co-assembled polymers can lead to flexible and tunable colorimetric cellulosic sensors. Despite the advantages of cellulose-based amorphous photonic crystal (APC) pigments or glitters as sustainable and visually captivating sensors, there are still problems in efficient preparation and co-assembly conditions. This editorial will provide a brief discussion of the benefits, applications, and challenges of cellulosebased APCs. [ABSTRACT FROM AUTHOR]

Background: Osteoarthritis (OA) was a chronic degenerative joint disease. The dysregulation of circular RNAs (circRNAs) has been identified in OA progression. However, the function and regulation mechanism of circ_0114876 in OA remains largely unknown. Method: Firstly, we used LPS-treated £28/I2 cells as a cellular model of OA. Quantificational real-time poly- merase chain reaction (qRT-PCR) was used to determine tile expression levels of circ_0114876, miRNA-1227-38 and ADAM10 in OA chondrocytes. Cell Counting Kit-8 (CCKB), 5-ethynyl-20-deoxyuridine (EdU) incorporation assays, flow cytometry, Enzyme-linked immunosorbent assay (ELISA) kit, and western blot were applied to confirm cell proliferation, apoptosis, inflammation, and extracellular matrix. of circ_0114876 in vitro. The interaction between cim_0114876 and its downstream target (miR-1227-3p) and mRNA target ADAM metallopeptidase domain 10 (ADAM10), was evaluated by luciferase assay and RNA immunoprecipitation (RIP) assay Result.· Circ-0114876 and ADAM10 were upregulated and miR-1227-3p was decreased in OA tissues and LPStreated chondrocytes. Low expression of cim_0114876 promoted proliferation and inhibited apoptosis, inflammation, and extracellular matrix of the LPS-treated chondrocytes. Mechanistically, circ_01 14876 functioned in human chondrocytes through targeting miR-1227-3p and ADAM10. Furthermore, miRNA-1227-3p inhibitor reversed the effect of circ_0114876 knockdown on the OA chondrocytes, and ADAM10 overexpression reversed the effect of miR-1227-3p mimic on the OA cliondrocytes. Conclusion: Cim_01 14876 was increased in OA tissues and cells. Circ_01 14876 facilitated the progression in the LPS-induced OA cell model via regulating the miR-1227-3p/ADAM10 axis. This study would provide a potentially effective Lherapeutic strategy for OA progression. [ABSTRACT FROM AUTHOR]

Liquid-junction-free reference electrodes that contact the sample through an ionic-liquid-doped, hydrophobic polymer membrane have attracted attention because they offer an alternative to reference electrodes with conventional salt bridges. In this work, liquid-junction-free reference electrodes were developed using plasticized poly(vinyl chloride) membranes doped with the ionic liquid (IL) 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide. Three-dimensionally ordered macroporous (3DOM) carbon substrates infused with this ionic liquid phase were used as solid contacts for these reference membranes. As in prior work with ionophore-based 3DOM carbon-contact ion-selective electrodes, the long-term stability of the liquid-junction-free reference electrodes was excellent, with potential drifts as low as 42 μV/h over 26 days. Successful measurements of pH in milk were performed and, to the best of our knowledge, are the first example of the use of liquid-junction-free reference electrodes in complex real-life samples. A thorough analysis of their performance at low pH revealed protonation of the ionic liquid anion (L-) and formation of LHL- type of associates in the reference electrode membrane, effects not observed in prior work. Also, when reference membranes were mounted into conventional electrode bodies with inner filling solutions that contained no ionic liquid ions, zero-current ion fluxes across the sample/membrane interface occurred, as previously only seen for ionophore-doped ion-selective membranes. Understanding these effects will be crucial to the design of liquid-junction-free reference electrodes suitable for other applications. [ABSTRACT FROM AUTHOR]

The long-lasting humoral immunity induced by viral infections or vaccinations depends on memory B cells with greatly increased affinity to viral antigens, which are evolved from germinal center (GC) responses. However, it is unclear whether antiviral memory B cells represent a distinct subset among the highly heterogeneous memory B cell population. Here, we examined memory B cells induced by a virus-mimicking antigen at both transcriptome and epigenetic levels and found unexpectedly that antiviral memory B cells exhibit an enhanced innate immune response, which appeared to be facilitated by the epigenetic memory that is established through the memory B cell development. In addition, T-bet is associated with the altered chromatin architecture and is required for the formation of the antiviral memory B cells. Thus, antiviral memory B cells are distinct from other GC-derived memory B cells in both physiological functions and epigenetic landmarks. [ABSTRACT FROM AUTHOR]

Previous studies have suggested a possible association between metals and sleep disorders. This study aimed to explore the association between Zn, Cu, Se, Mg and Ca and sleep disorders in single and multi-metal co-exposure models. Logistic regression models, restricted cubic spline model (RCS), Quantile g computation (Q-gcomp), Weighted Quantile Sum (WQS), and Bayesian kernel machine regression (BKMR) models were used to investigate the association between metal levels and sleep disorders. Logistic regression showed that in the total population, the second, third, and fourth quartile Zn concentration exhibited a lower risk of sleep disorders compared with the first quartile, with odds ratios (ORs) of 0.783, 0.711, and 0.704, respectively. Compared with Zn/Cu and Zn/Se in the first quartile, the third and fourth quartiles showed a lower risk of sleep disorders. In the 30–59 years group, the risk of sleep disorders was 0.699 times greater for the fourth quartile Mg concentration than that for the first quartile. The risk of sleep disorders in Mg/Ca concentration in the third quartile was 0.737 times higher than in the first quartile. Q-gcomp, WQS, and BKMR model analysis showed the negative overall effect of mixtures of the five metals on sleep disorders, with Zn being the largest contributor. Our study showed that plasma Zn, Mg, Zn/Cu, Zn/Se, and Mg/Ca reduced the risk of sleep disorders, and the combined effect of multiple metals was negatively associated with the risk of sleep disorders, with Zn being the largest contributor to this relationship. [Display omitted] • Plasma Zn and Mg was negatively correlated with sleep disorder. • Plasma metal ratio Zn/Cu, Zn/Se and Mg/Ca was negatively correlated with sleep disorder. • The combined effect of Zn, Cu, Se, Mg and Ca five metals was negatively correlated with sleep disorder. [ABSTRACT FROM AUTHOR]

The catalytic activity of a transition metal (host) oxide can be influenced by doping with a second cation (dopant), but the key factors dominating the activity of the doped catalyst are still controversial. Herein, CeO2 doped with Ni, Mn, and Y catalysts prepared using aerosol pyrolysis were used to demonstrate the positive, negative, and additive effects on CO oxidation as a model reaction. Various characterization results indicated that Ni, Mn, and Y had been successfully doped into the CeO2 lattice. The catalytic activities of each catalyst for CO conversion were in the order of Ni–CeO2 > Mn–CeO2 > CeO2 > Y–CeO2. Operando DRIFTS-MS and various characterization methods were applied to reveal the intrinsic nature of the doping effects. The accumulation rate of the surface bidentate carbonates determined the CO oxidation. A definition to evaluate the doping effect was proposed, which is anticipated to be useful for developing a rational catalyst with a high CO oxidation activity. The CO oxidation reactivities displayed strong correlations with the surface factors obtained from operando DRIFTS-MS analysis and the structure factors from XPS and Raman analyses. [ABSTRACT FROM AUTHOR]

We employed ab initio calculations to identify a class of crystalline materials of MSi (M=Fe, Co, Mn, Re, Ru) having double-Weyl points in both their acoustic and optical phonon spectra. They exhibit novel topological points termed "spin-1 Weyl point" at the Brillouin zone center and "charge-2 Dirac point" at the zone corner. The corresponding gapless surface phonon dispersions are two helicoidal sheets whose isofrequency contours form a single noncontractible loop in the surface Brillouin zone. In addition, the global structure of the surface bands can be analytically expressed as double-periodic Weierstrass elliptic functions. [ABSTRACT FROM AUTHOR]

Despite the availability of abundant literature on green tea, studies on the use of L-theanine (an amino acid found only in green tea) as a feed additive in poultry especially broiler are limited. So, this study was conducted to explore the effects of L-theanine on the intestinal microbiome and immune response in a broiler. A total of 400-d-old chicks were randomly divided into four treatment groups (A, B, C, and D) using a complete randomized design. Treatments were as follows: A, control (basal diet); B, basal diet + 100 mg L-theanine/kg diet; C, basal diet + 200 mg L-theanine/kg diet; and D, basal diet + 300 mg L-theanine/kg diet. Mucosal samples from ileum and jejunum of broiler chicken were extracted at 21 and 42 d of age. Extraction of genomic DNA was followed by amplification of V3 and V4 hypervariable regions of 16S ribosomal RNA. After Illumina sequencing, results revealed that treatment with L-theanine significantly increased the population of Lactobacillus in ileum and jejunum as compared to a control group, but the higher population was observed in jejunum at both 21 and 42 d of age. The overall diversity of the jejunum microbiome in the treatment group was significantly lower than that of the ileum and control group (P < 0.05). Results of this study revealed that mRNA expression of TLRs (TLR-2 and TLR-4) and cytokines (TNF-α, IFN-γ, and IL-2) was decreased in response to treatment with L-theanine. Moreover, the negative correlation of abundance of Lactobacillus was observed with expression of IL-2 and IFN-γ in the intestine and these effects were highly significant (P < 0.01). In summary, our finding revealed that dietary supplementation of L-theanine exhibited a positive influence on intestinal bacteria by supporting beneficial microbes like Lactobacillus while decreasing harmful microbes like Clostridium. [ABSTRACT FROM AUTHOR]

Normally, the gut microbiota has a mutually beneficial association with host health and maintains its commensal status in mammals. Conversely, it can also negatively influence host physiology under some certain circumstances, including obesity and other disease states. Although numerous gut microbial functions directly affect the gastrointestinal tract, in this paper, we focus on the influences of the gut microbiota on host adipose tissue and energy metabolism, particularly lipometabolism. We thoroughly discuss two important microbial products, short-chain fat acids and lipopolysaccharides, which are linked to several mechanisms involved in obesity and adipose, including differentiation, energy metabolism and immunity. Furthermore, this review also addresses some potentially beneficial functions of probiotics, which can serve to prevent or alleviate host pathological states, including dysbacteriosis, obesity, low-grade inflammation and metabolic syndrome. [ABSTRACT FROM AUTHOR]

Background: PHD-finger domain protein 5A (PHF5A) is a highly conserved small transcriptional regulator also involved in pre-mRNA splicing; however, its biological functions and molecular mechanisms in non-small cell lung cancer (NSCLC) have not yet been investigated. The purpose of this study was to determine the functional relevance and therapeutic potential of PHF5A in lung adenocarcinoma (LAC). Methods: The expression of PHF5A in LAC tissues and adjacent non-tumor (ANT) tissues was investigated using immunohistochemistry of a tissue microarray, qRT-PCR, western blot and bioinformatics. The function of PHF5A was determined using several in vitro assays and also in vivo assay by lentiviral vector-mediated PHF5A depletion in LAC cell lines. Results: PHF5A was highly upregulated in LAC tissues compared with the ANT counterparts and closely associated with tumor progression and poor patient prognosis. These results were further confirmed by findings of the TCGA database. Moreover, functional studies demonstrated that PHF5A knockdown not only resulted in reduced cell proliferation, increased cell apoptosis and cell cycle arrest, but also suppressed migration and invasion in LAC cells. PHF5A silencing was also found to inhibit LAC tumor growth in nude mice. Microarray and bioinformatics analyses revealed that PHF5A depletion led to dysregulation of multiple tumor signaling pathways; selected factors in key signaling pathways were verified in vitro. Conclusions: The data suggest for the first time that PHF5A is an oncoprotein that contributes to LAC progression by regulating multiple signaling pathways and may constitute a prognostic factor and potential new therapeutic target in NSCLC. [ABSTRACT FROM AUTHOR]

We propose an indoor positioning system with visible light communication (VLC) technology, which employs a dimensionality reduction (DR) algorithm based on the received signal intensity, to eliminate the dead zone of positioning. Simulations are conducted for five altitude levels with dimensions of 5 m × 5 m × 4 m to verify the performance of the proposed DR algorithm. The result shows that subcentimeter accuracy in positioning can be obtained at five levels in three-dimensional space and that there exists no dead zone. Good robustness against the signal-to-noise ratio, space size, and transmission power is also verified via extensive tests. [ABSTRACT FROM AUTHOR]

The traditional systemic chemotherapy through intravenous infusion of doxorubicin (DOX) has many side effects. The aim of this study was to develop a PLGA-based DOX-loaded implant and to evaluate the efficacy and drug metabolism distribution of the implant in intratumoral chemotherapy for osteosarcoma (OS). In this study, implants containing DOX, poly(D,L-lactide-co-glycolide), and polyethylene glycol 4000 were prepared by melt-molding method. Then, the antitumor activity and systemic drug distribution of the implants were tested in a K7M2 OS bearing mouse model. The scanning electron microscope images showed that DOX was uniformly dispersed in the polymer matrix. Both the in vitro and in vivo release profiles of implants are characterized by three-phase release. Implantation of DOXloaded implants into tumors can inhibit tumor growth in a dose-dependent manner. The pharmacokinetic behavior shows that intratumor chemotherapy through implants has a much higher drug concentration in tumors than in normal tissues, which may be the reason for improving antitumor activity and reducing systemic side effects. In summary, the drug release of the implants prepared in this study is sustained and stable, which promotes long-term local accumulation of drugs in tumors, improves the efficacy of chemotherapy and has low toxicity to normal tissues. [ABSTRACT FROM AUTHOR]

We characterised an A-type cyclin SlCycA3 (AJ243453) from tomato (Solanum lycopersicum L.). Phylogenetic analysis based on the deduced amino acid sequence revealed that SlCycA3 was 71% identical to A3-type cyclin in Nicotiana tabacum L. (CAA63540), 48% identical to its homologue found in Arabidopsis thaliana (NP_199122), and 48% identical to its homologue in Pisum sativum L. (CAB77269). SlCycA3 gene was transformed into Arabidopsis plants in order to study its function. The hypocotyl length of transgenic plants was approximately half the length of wild-type plants, and the cell size in the transgenic lines was also smaller. The transgenic plants had longer roots than the wild type. Overexpression of SlCycA3 gene accelerated the cell cycle from G1/S transition to early M-phase, thereby accelerating the cell division. When the plants were treated with IAA and 3-indolebutyric acid (IBA) for 2 days, the transgenic plants produced more lateral roots than wild type. Treatment with IBA significantly increased the cell number in the G2-phase in transgenic plants compared with wild type after treatment for 10 days, whereas the proportion of cells in the S-phase was strongly increased by IAA treatment both in wild-type and transgenic plants. These results suggest a possible key role for cyclin in regulating root growth and development and provide some evidence of cell division underlying hormone treatment in plants. Since the connection between cyclins and plant development involving plant hormones is poorly understood, we characterise the SlCycA3 gene to determine the effect of A3-type cyclin gene on cell-cycle-related plant growth and its regulation mechanisms under auxin treatment. Our results showed that overexpression of the SlCycA3 gene accelerated root growth and development. Cyclin abundance may function as a regulator to control root growth in response to plant hormone treatment. [ABSTRACT FROM AUTHOR]

Sleep deprivation has profound influence on several aspects of health and disease. Mitochondria dysfunction has been implicated to play an essential role in the neuronal cellular damage induced by sleep deprivation, but little is known about how neuronal mitochondrial ultrastructure is affected under sleep deprivation. In this report, we utilized electron cryo-tomography to reconstruct the three-dimensional (3-D) mitochondrial structure and extracted morphometric parameters to quantitatively characterize its reorganizations. Isolated mitochondria from the hippocampus and cerebral cortex of adult male Sprague-Dawley rats after 72 h of paradoxical sleep deprivation (PSD) were reconstructed and analyzed. Statistical analysis of six morphometric parameters specific to the mitochondrial inner membrane topology revealed identical pattern of changes in both the hippocampus and cerebral cortex but with higher significance levels in the hippocampus. The structural differences were indistinguishable by conventional phenotypic methods based on two-dimensional electron microscopy images or 3-D electron tomography reconstructions. Furthermore, to correlate structure alterations with mitochondrial functions, high-resolution respirometry was employed to investigate the effects of PSD on mitochondrial respiration, which showed that PSD significantly suppressed the mitochondrial respiratory capacity of the hippocampus, whereas the isolated mitochondria from the cerebral cortex were less affected. These results demonstrate the capability of the morphometric parameters for quantifying complex structural reorganizations and suggest a correlation between PSD and inner membrane architecture/respiratory functions of the brain mitochondria with variable effects in different brain regions. [ABSTRACT FROM AUTHOR]

The article proposes oxide perovskites as a versatile platform in which to study topological phonons and their manipulation with light. It mentions that perovskite oxides exhibit a rich variety of structural phases hosting different physical phenomena that generate multiple technological applications, along with discusses the photoexcitation phenomenon.

Topological materials have novel properties both in their bulk and boundaries, thereby attracting a wide interest in the theoretical and experimental communities. The recent development of the topological quantum chemistry and symmetry-based indicator theory in this field has significantly simplified the procedure for determining the topological properties of nonmagnetic crystalline materials. Accordingly, a large number of new topological materials have been found by scanning large crystal databases. This study provides details on the algorithm used in the Catalogue of Topological Electronic Materials. Moreover, based on the algorithm, we develop an automatic package named SymTopo, which calculates the symmetry representations of any given nonmagnetic crystalline material and predicts its topological properties. This package may facilitate the discovery of more topological materials in the future. [ABSTRACT FROM AUTHOR]

We examined the impact of feedback seeking, including feedback inquiry and monitoring, on career adaptability via the mediator of supervisor feedback environment and the moderator of person--organization fit (P--O fit). Participants were 415 full-time employees in China, who completed the research measures in 3 waves each spaced 3 months apart. The results revealed that supervisor feedback environment mediated the relationship between feedback seeking and career adaptability, and that the effect of feedback inquiry and feedback monitoring on the supervisor feedback environment was moderated by P--O fit. The positive effect of feedback inquiry and feedback monitoring on career adaptability was significant only when P--O fit was poor (vs. good). Supervisors should encourage employees to seek feedback and organizations could also design training sessions to improve employee career adaptability, promote employee performance, and facilitate career development. [ABSTRACT FROM AUTHOR]

Purpose: The study aims to investigate, using anodal transcranial direct current stimulation (A-tDCS), over which site, the left lip region of primary motor cortex (M1) or the Broca's area, there would be better recovery from apraxia of speech (AoS) in patients with poststroke aphasia and to examine for altered activation in speech-related areas after tDCS with nonlinear electroencephalography (EEG). Method: Fifty-two patients with AoS were randomized into A-tDCS over the left M1 (A-tDCS-M1), Broca's area, and sham tDCS groups who underwent 10 sessions of tDCS and speech treatment for 5 days. The EEG nonlinear index of approximate entropy was calculated for 6 subjects in each group before and after treatment. Results: After treatment, the change in speech-language performance improved more significantly in the A-tDCS-M1 group than the other 2 groups (p < .05). EEG approximate entropy indicated that both A-tDCS groups could activate the stimulated sites; the improvement in the A-tDCS-M1 group was correlated with high activation in the dorsal lateral prefrontal cortex and Broca's areas of the left hemisphere in addition to the stimulated site. Conclusion: A-tDCS over the left M1 can improve the speech function in patients with poststroke aphasia and severe AoS and excite and recruit more areas in the motor speech network. [ABSTRACT FROM AUTHOR]

Although comprehensive progress has been made in the area of coordination polymer (CP)/metal-organic framework (MOF)-based proton-conducting materials over the past decade, searching for a CP/MOF with stable, intrinsic, high anhydrous proton conductivity that can be directly used as a practical electrolyte in an intermediate-temperature proton-exchange membrane fuel cell assembly for durable power generation remains a substantial challenge. Here, we introduce a new proton-conducting CP, (NH4)3[Zr(H2/3PO4)3] (ZrP), which consists of one-dimensional zirconium phosphate anionic chains and fully ordered charge-balancing NH4+ cations. X-ray crystallography, neutron powder diffraction, and variable-temperature solid-state NMR spectroscopy suggest that protons are disordered within an inherent hydrogen-bonded infinite chain of acid-base pairs (N-H⋯O-P), leading to a stable anhydrous proton conductivity of 1.45 x 10-3 S·cm-1 at 180 °C, one of the highest values among reported intermediate-temperature proton-conducting materials. First-principles and quantum molecular dynamics simulations were used to directly visualize the unique proton transport pathway involving very efficient proton exchange between NH4+ and phosphate pairs, which is distinct from the common guest encapsulation/dehydration/superprotonic transition mechanisms. ZrP as the electrolyte was further assembled into a H2/O2 fuel cell, which showed a record-high electrical power density of 12 mW·cm-2 at 180 °C among reported cells assembled from crystalline solid electrolytes, as well as a direct methanol fuel cell for the first time to demonstrate real applications. These cells were tested for over 15 h without notable power loss. [ABSTRACT FROM AUTHOR]

Dust contamination to ventilation systems is a common issue for mine operators during underground coal mining. In the present study, dust dispersion driven by a hybrid ventilation system in an underground mine has been investigated via a computational fluid dynamics (CFD) model. Specifically, the numerical model was developed based on the Euler-Lagrange method where the trajectory of dispersed dusts was solved individually. Dust dispersion induced by turbulence was considered by a stochastic tracking model. Effects of key parameters (e.g., gas velocity and exhaust duct length) on dust dispersion characteristics throughout the coal roadway have been examined. The results showed that the distribution of dusts exhibited extreme non-uniformity with a significantly higher concentration present near the mining face, particularly on the exhaust side. The cross-sectional average dust concentration substantially decreased along the axial direction in the front part of the coal roadway. Intense circumfluence and secondary sedimentation of dusts were found to be the main mechanisms that drove the non-uniform distribution of dusts. The model is shown to be capable of reproducing the dust dispersion process captured in the experiments and the prediction results agree well with the experimental data. [ABSTRACT FROM AUTHOR]

Chronic stress occurs in everyday life, and often results in memory impairments and depressive symptoms. Resveratrol is a natural polyphenol that possesses numerous biological properties, including potent antidepressant-like effects. The present study aimed to examine the effects of resveratrol treatment on chronic restraint stress (CRS)-induced cognitive impairment and to explore the underlying molecular mechanisms. Male Wistar rats were exposed to CRS for 21 days in order to induce depressive-like behavior. The results demonstrated that CRS (6 h/day, 21 days) was able to induce cognitive deficits in rats, as evidenced by Morris water maze and novel object recognition tests. In addition, CRS exposure significantly decreased the mRNA and protein expression levels of hippocampal brain-derived neurotrophic factor (BDNF) in the rats. Conversely, chronic treatment with resveratrol (80 mg/kg, i.p.; 21 days) significantly prevented the behavioral and biochemical alterations induced by CRS. The effects of resveratrol were nearly identical to those observed with fluoxetine treatment. In conclusion, the present study demonstrated that resveratrol may be a potential therapeutic agent for the treatment of chronic stress-induced cognitive impairments, and its underlying molecular mechanism may be associated with the increased levels of hippocampal BDNF. [ABSTRACT FROM AUTHOR]

Cucumber (Cucumis sativus) is a widely grown cucurbitaceous vegetable that exhibits a relatively high capacity for silicon (Si) accumulation, but the molecular mechanism for silicon uptake remains to be clarified. Here we isolated and characterized CsLsi1, a gene encoding a silicon transporter in cucumber (cv. Mch-4). CsLsi1 shares 55.70 and 90.63% homology with the Lsi1s of a monocot and dicot, rice (Oryza sativa) and pumpkin (Cucurbita moschata), respectively. CsLsi1 was predominantly expressed in the roots, and application of exogenous silicon suppressed its expression. Transient expression in cucumber protoplasts showed that CsLsi1 was localized in the plasma membrane. Heterologous expression in Xenopus laevis oocytes showed that CsLsi1 evidenced influx transport activity for silicon but not urea or glycerol. Expression of cucumber CsLsi1-mGFP under its own promoter showed that CsLsi1 was localized at the distal side of the endodermis and the cortical cells in the root tips as well as in the root hairs near the root tips. Heterologous expression of CsLsi1 in a rice mutant defective in silicon uptake and the over-expression of this gene in cucumber further confirmed the role of CsLsi1 in silicon uptake. Our results suggest that CsLsi1 is a silicon influx transporter in cucumber. The cellular localization of CsLsi1 in cucumber roots is different from that in other plants, implying the possible effect of transporter localization on silicon uptake capability. [ABSTRACT FROM AUTHOR]

A direct difunctionalization protocol of alkenes with nitriles and thiols toward β-acetamido sulfide derivatives has been proposed under metal-free synthesis conditions. The present protocol provides the facile and highly efficient synthesis of various β-acetamido sulfides in a scaled-up manner with good to excellent yields simply using inexpensive molecular iodine as a catalyst, DMSO as a mild oxidant, and readily available thiols as thiolating reagents. [ABSTRACT FROM AUTHOR]

To comprehensively understand the bio-decolorization process of azo dyes at the molecular level, the transcriptional response of Escherichia coli K-12 to a highly polar azo dye, Acid Red 18 (AR 18), was investigated in this study using whole-genome DNA microarrays. The results showed that genes involved in the reductive decolorization of AR 18 displayed significant upregulation; they were followed by stress response genes. This result indicated that the former genes play more important roles in increasing the AR 18 resistance of E. coli . Moreover, mutants deficient in the functions of yqhD , fdhF , nrfABCD , frdBCD and dmsABC showed lower abilities of decolorizing AR 18 compared with wild type strain, indicating that these genes play important roles in AR 18 decolorization. The above findings reveal that a network of genes is involved in AR 18 decolorization. [ABSTRACT FROM AUTHOR]

Objective Deficiency or reduced expression of signal transduction and activation of RNA family protein Quaking (Qki) is associated with developmental defects in neural and vascular tissues and the development of debilitating human diseases including colorectal cancer (CRC). However, the mechanisms underlying the aberrant downregulation or deficiency of Qki were uncertain. Design Expression of miR-574-5p, Qki5/6/7/7b splicing variants, b-catenin and p27Kip1 was determined in mouse and human CRC cells and tissues to investigate the post-transcriptional regulation of Qki isoforms by miR-574-5p and its impact on b-catenin/p27Kip1 signalling, cell cycle progression, proliferation, migration, invasion and tumour growth. Results In the CRC tissues of C57BL/6-Apcmin/+ mice, miR-574-5p was found to be significantly upregulated and negatively correlated with the expression of Qki but positively correlated with the expression of b-catenin. In mouse and human CRC cells, miR-574-5p was shown to regulate Qki isoforms (Qki6/7 in particular) posttranscriptionally and caused altered expression in b-catenin and p27Kip1, increased proliferation, migration and invasion and decreased differentiation and cell cycle exit. Furthermore, in clinical CRC tissues, miR-574-5p was shown to be greatly upregulated and inversely correlated with the expression of Qkis. Finally, inhibition of miR-574-5p was shown to suppress the growth of tumours in the nude mice. Conclusions Together, these novel findings suggest that miR-574-5p is a potent ribo-regulator for Qkis and that aberrant miR-574-5p upregulation can be oncogenic. [ABSTRACT FROM AUTHOR]

Previous work has shown that protein molecules can be trapped between the conductive surfaces presented by a metal-coated AFM probe and an underlying planar substrate where their molecule-specific conductance characteristics can be assayed. Herein, we demonstrate that transport across such a derived metal−protein−electrode junction falls within three, pressure-dependent, regimes and, further, that pressure-dependent conductance can be utilized in analyzing temporal variations of protein fold. Specifically, the electronic and mechanical properties of the metalloprotein azurin have been characterized under conditions of anisotropic vertical compression through the use of a conducting atomic force microscope (CP-AFM). By utilizing the ability of azurin to chemically self-assemble on the gold surface presented either by the apex of a suitably coated AFM probe or a planar metallic surface, molecular-level transport characteristics are assayable. Under conditions of low force, typically less than 2 nN, the weak physical and electronic coupling between the protein and the conducting contacts impedes tunneling and leads to charge buildup followed by dielectric breakdown. At slightly increased force, 3−5 nN, the copper protein exhibits temporal electron occupation with observable negative differential resistance, while the redox-inactive zinc mutant does not. At imposed loads greater than 5 nN, appreciable electron tunneling can be detected even at low bias for both the redox-active and -inactive species. Dynamic current−voltage characteristics have been recorded and are well-described by a modified Simmons tunneling model. Subsequent analyses enable the electron tunneling barrier height and barrier length to be determined under conditions of quantified vertical stress. The variance observed describes, in essence, the protein's mechanical properties within the confines of the tunnel junction. [ABSTRACT FROM AUTHOR]