Search

When an offshore oil field completed and put into production, new subsea pipelines and the new cable need to be established. Cable protection pipe clamp is used to fix cable protection pipe on the jacket. In order to avoid the problem of traditional steel structure clamp splice, counterpoint, fastening difficulty when installed cable protection pipe under water, reduce the risk and workload of under water, This paper develop a new type of portable connecting riser clamp -"backpack clamp" which solve the riser cable protection pipe difficult underwater installation problem. The main structure of backpack clamp used three valves type structure. The load characteristic of a clamping device was determined by the Morison equation which was a classical theory. Clamp device underwater mechanics analysis model was established. The minimum tension pre-tightening force was determined. The results show that the strength of the base meets the requirements after strength analysis with finite element analysis method, stability and strength experiments, which means the clamp based on resin matrix composite is feasible. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the diagnostic concordance of plasma epidermal growth factor receptor (EGFR) mutation using droplet digital polymerase chain reaction (ddPCR) with tumor tissue samples and the predictive clinical significance of plasma EGFR mutation concentration. Plasma DNA samples from patients with non-small cell lung cancer (NSCLC) were analyzed for EGFR exon 21 codon 858 (L858R) mutation, deletion of exon 19 (ex19del) and exon 20 codon 790 (T790M) mutation using ddPCR. Firstly, the mutations in the plasma samples were compared with the matched tumor samples to determine the concordance. Secondly, image examination follow-ups were analyzed to assess the association between plasma EGFR mutation concentration and patients' response to EGFR-tyrosine kinase inhibitors (TKIs). A total of 51 patients with NSCLC were enrolled, including 48 newly diagnosed patients. Compared with tumor tissue samples, the sensitivity and specificity of ddPCR were 76.19% (16/21) and 96.55% (28/29) for mutant L858R, and 88.89% (8/9) and 100% (41/41) for ex19del, respectively. No patient exhibited the T790M mutation in the tumor tissue or plasma samples. Furthermore, 5 patients with the L858R mutation and 4 patients with ex19del in plasma and tumor tissue samples had been followed up with image examination for ≥3 months following EGFR-TKI treatment. The baseline mutant EGFR concentrations were positively correlated with a reduction in tumor burden (Spearman's r=0.7000, P=0.0358). When analyzed separately, ex19del concentrations (Spearman's r=1.0000, P<0.0001) were also positively correlated with the reduction, while mutant L858R concentrations were not (Spearman's r=0.7000, P=0.1881). In the present study, detection of plasma EGFR mutations using ddPCR exhibited sufficient concordance with tumor tissue sample results. Baseline plasma mutant EGFR and ex19del concentrations were significantly and positively correlated with response to EGFR-TKIs. [ABSTRACT FROM AUTHOR]

Both light and temperature have dramatic effects on plant development. Phytochrome photoreceptors regulate plant responses to the environment in large part by controlling the abundance of PHYTOCHROME INTERACTING FACTOR (PIF) transcription factors. However, the molecular determinants of this essential signaling mechanism still remain largely unknown. Here, we present evidence that the BLADE-ON-PETIOLE (BOP) genes, which have previously been shown to control leaf and flower development in Arabidopsis, are involved in controlling the abundance of PIF4. Genetic analysis shows that BOP2 promotes photo-morphogenesis and modulates thermomorphogenesis by suppressing PIF4 activity, through a reduction in PIF4 protein level. In red-light-grown seedlings PIF4 ubiquitination was reduced in the bop2 mutant. Moreover, we found that BOP proteins physically interact with both PIF4 and CULLIN3A and that a CULLIN3-BOP2 complex ubiquitinates PIF4 in vitro. This shows that BOP proteins act as substrate adaptors in a CUL3BOP1/BOP2 E3 ubiquitin ligase complex, targeting PIF4 proteins for ubiquitination and subsequent degradation. [ABSTRACT FROM AUTHOR]

Lumbar intervertebral disc herniation (LIDH), as the main contributor to low back pain and sciatica, imposes a heavy burden on both the individual and society. Non-operative treatment or conservative treatment has proven effective in alleviation of the symptoms of LIDH and are considered to be a first-line choice for most cases. Active lifestyle, physical therapy, complementary and alternative medicine therapy or Traditional Chinese medicine (TCM) therapy, and pharmacotherapy are routinely used as effective non-operative treatment for LIDH patients. However, how to choose one or several conservative treatments with higher efficacy, less side effects, minimal injury, and low cost is still a challenge for doctors and LIDH patients. Furthermore, there are some national characteristics for some conservative treatments in different countries, which bring difficulties for the widespread use of these methods. Here we initiated a search on the non-operative treatment especially TCM therapy for LIDH mainly using PubMed, Web of Science, China National Knowledge Internet (CNKI), and Chinese biomedicine database since the 1980s with no restriction of language. According to these related references, we gave a narrative review which emphasizes up-to-date knowledge regarding the effectiveness and safety of various conservative methods with special consideration for TCM therapy including acupuncture, autonomy, Chinese massage, and Chinese herbal medicines, for LIDH treatment. We hope this review will further contribute to an understanding of conservative treatment as an important choice for LIDH patients and provide useful information for the development of more effective conservative methods for LIDH treatment. [ABSTRACT FROM AUTHOR]

RNA splicing factor SF3B1 is recurrently mutated in various cancers, particularly in hematologic malignancies. We previously reported that coexpression of Sf3b1 mutation and Atm deletion in B cells, but not either lesion alone, leads to the onset of chronic lymphocytic leukemia (CLL) with CLL cells harboring chromosome amplification. However, the exact role of Sf3b1 mutation and Atm deletion in chromosomal instability (CIN) remains unclear. Here, we demonstrated that SF3B1 mutation promotes centromeric R-loop (cen-R-loop) accumulation, leading to increased chromosome oscillation, impaired chromosome segregation, altered spindle architecture, and aneuploidy, which could be alleviated by removal of cen-R-loop and exaggerated by deletion of ATM. Aberrant splicing of key genes involved in R-loop processing underlay augmentation of cen-R-loop, as overexpression of the normal isoform, but not the altered form, mitigated mitotic stress in SF3B1-mutant cells. Our study identifies a critical role of splice variants in linking RNA splicing dysregulation and CIN and highlights cen-R-loop augmentation as a key mechanism for leukemogenesis. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to investigate the differences in the composition of microbial communities and related functions in hepatocellular carcinoma (HCC) tumours and matched normal tissues were investigated. Methods and Material: Tumour tissues and matched normal samples were collected from 30 HCC patients. Genomic DNA was collected and subjected to sequencing of the V3 + V4 region of the 16S rRNA gene. The microbial community profiles and metabolic pathway predictions of the different groups were characterized and compared. Results: Tumour and adjacent tissues had similar microbiota compositions but differed in abundance. Proteobacteria and Firmicutes abundance decreased and Cyanobacteria and Acidobacteria abundance increased in the tumour tissue. The microbial community diversity was higher in the tumour tissues than in adjacent samples, with potentially more dominant taxa in the adjacent tissues, including Firmicutes, Proteobacteria, and Actinobacteria. Acidobacteria, Cyanobacteria, and Chloroflexi were the dominant microbes in tumour tissues. A total of 46 metabolic pathways were identified. Global and overview maps were the most abundant pathways, followed by carbohydrate metabolism, energy metabolism, metabolism of cofactors and vitamins, and membrane transport. The top 50 most highly correlated microbial genera included Klebsiella, Rhodococcus, Ochrobactrum, and Azoarcus. Fonticella, Haloimpatiens, Brevibacterium, and Acidothermus were positively correlated with other microbial genera. The microbiota of adjacent tissues was more robust in the network analysis. Conclusions: This study revealed differences in microbial composition between HCC tumour tissues and normal tissues and differences in microbial abundance associated with different metabolic functions. Cyanobacteria, Proteobacteria, and Actinobacteria may play important roles in HCC. [ABSTRACT FROM AUTHOR]

Motivation: The discovery of transcription factor binding site (TFBS) motifs is essential for untangling the complex mechanism of genetic variation under different developmental and environmental conditions. Among the huge amount of computational approaches for de novo identification of TFBS motifs, discriminative motif learning (DML) methods have been proven to be promising for harnessing the discovery power of accumulated huge amount of high-throughput binding data. However, they have to sacrifice accuracy for speed and could fail to fully utilize the information of the input sequences. Results: We propose a novel algorithm called CDAUC for optimizing DML-learned motifs based on the area under the receiver-operating characteristic curve (AUC) criterion, which has been widely used in the literature to evaluate the significance of extracted motifs. We show that when the considered AUC loss function is optimized in a coordinate-wise manner, the cost function of each resultant sub-problem is a piece-wise constant function, whose optimal value can be found exactly and efficiently. Further, a key step of each iteration of CDAUC can be efficiently solved as a computational geometry problem. Experimental results on real world high-throughput datasets illustrate that CDAUC outperforms competing methods for refining DML motifs, while being one order of magnitude faster. Meanwhile, preliminary results also show that CDAUC may also be useful for improving the interpretability of convolutional kernels generated by the emerging deep learning approaches for predicting TF sequences specificities. [ABSTRACT FROM AUTHOR]

Progress in the treatment options for small cell lung cancer (SCLC) remains poor. Concerns exist regarding the efficacy of bevacizumab in SCLC. The present study aimed to evaluate the efficacy of bevacizumab in extensive stage (ES)‑SCLC. A meta‑analysis on studies conducted and listed on the Medline, Cochrane Trials, ASCO, ESMO and Clinical-Trial databases, and Chinese databases prior to April 2015 was performed. All clinical trials in which patients with ES‑SCLC were treated with bevacizumab were considered. Survival rates at specific time points were extracted from the reported survival curves. Hazard ratios (HR) for progression‑free survival (PFS) and overall survival (OS), rates for PFS, OS, overall response rate (ORR), and side‑effects were synthesized using random‑effects or fixed‑effects model. Two randomized control trials (RCT) (176 patients) and six single‑arm trials (292 patients) were identified. In RCTs, no statistically significant differences were observed in PFS [HR, 0.70; 95% confidence interval (CI), 0.41‑1.19; P=0.19] or OS (HR, 1.21; 95% CI, 0.84‑1.75; P=0.31). In the first‑line trials, pooled 6‑month and 1‑year PFS rates were 57% (95% CI, 39‑76%) and 10% (95% CI, 4‑16%), respectively. Synthesized 1‑year and 2‑year OS rates were 45% (95% CI, 36‑54%) and 10% (95% CI, 6‑14%), respectively. Reported median PFS and OS times for pretreated patients were 2.7‑4.0 months and 6.3‑7.4 months, respectively. Pooled ORRs were 71% (95% CI, 59‑82%) in the first‑line trials and 18% (95% CI, 11‑25%) in the second‑line trials. The most common types of reported toxicities were chemotherapy‑associated, including neutropenia, leukopenia, fatigue and thrombocytopenia. According to the RCTs, bevacizumab did not appear to improve the PFS or OS for patients with ES‑SCLC, with low quality of evidence. Due to the disappointing pooled efficacy in the single‑arm trials, more clinical studies on bevacizumab in SCLC may not be valuable, although the evidence was with low quality. [ABSTRACT FROM AUTHOR]

This paper discusses the control of the linear switched reluctance machines (LSRMs) network for the zero phase-difference tracking to a sinusoidal reference. The dynamics of each LSRM is derived by online system identification and modeled as a second-order linear system. Accordingly, based on the coupled harmonic oscillators synchronization manner, a distributed control strategy is proposed to synchronize each LSRMstate to a virtual LSRMnode representing the external sinusoidal reference for tracking it with zero phase-difference. Subsequently, a simulation scenario and an experimental platform with the identical parameter setup are designed to investigate the tracking performance of the LSRMs network constructed by the proposed distributed control strategy. Finally, the simulation and experimental results verify the effectiveness of the proposed LSRMs network controller, and also prove that the coupled harmonic oscillators synchronization method can improve the synchronization tracking performance and precision. [ABSTRACT FROM AUTHOR]

Background: Nicotinic acetylcholine receptors (nAChRs) play an important role in cellular physiology and human nicotine dependence, and are closely associated with many human diseases including cancer. For example, previous studies suggest that nAChRs can re-wire gene regulatory networks in lung cancer cell lines. However, the tissue specificity of nAChRs genes and their regulation remain unexplored. Result: In this study, we integrated data from multiple large genomic consortiums, including ENCODE, Roadmap Epigenomics, GTEx, and FANTOM, to define the transcriptomic and epigenomic landscape of all nicotinic receptor genes across many different human tissues and cell types. We found that many important nAChRs, including CHRNA3, CHRNA4, CHRNA5, and CHRNB4, exhibited strong non-neuronal tissue-specific expression patterns. CHRNA3, CHRNA5, and CHRNB4 were highly expressed in human colon and small intestine, and CHRNA4 was highly expressed in human liver. By comparing the epigenetic marks of CHRNA4 in human liver and hippocampus, we identified a novel liverspecific transcription start site (TSS) of CHRNA4. We further demonstrated that CHRNA4 was specifically transcribed in hepatocytes but not transcribed in hepatic sinusoids and stellate cells, and that transcription factors HNF4A and RXRA were likely upstream regulators of CHRNA4. Our findings suggest that CHRNA4 has distinct transcriptional regulatory mechanisms in human liver and brain, and that this tissue-specific expression pattern is evolutionarily conserved in mouse. Finally, we found that liver-specific CHRNA4 transcription was highly correlated with genes involved in the nicotine metabolism, including CYP2A6, UGT2B7, and FMO3. These genes were significantly downregulated in liver cancer patients, whereas CHRNA4 is also significantly down-regulated in cancer-matched normal livers. Conclusions: Our results suggest important non-neuronally expressed nicotinic acetylcholine receptors in the human body. These non-neuronal expression patterns are highly tissue-specific, and are epigenetically conserved during evolution in the context of non-conserved DNA sequence. [ABSTRACT FROM AUTHOR]

Repeat transcatheter arterial chemoembolization (TACE) becomes more challenging for patients with intrahepatic biloma following TACE for hepatocellular carcinoma (HCC).The purpose of this study was to investigate the clinical course, incidence, imaging features and outcome and to explore the reasonable therapy scheme for intrahepatic biloma following TACE for HCC.A total of 4,695 TACE procedures were performed for 1,923 patients with HCC. Twenty patients with intrahepatic biloma following TACE were studied retrospectively. The incidence of intrahepatic biloma was 1.04% in this study. The 20 patients underwent 55 TACE procedures (mean, 2.75). Portal vein invasion was found in half of the patients. Eleven patients developed round solitary or multiple cystic biloma, 6 patients had branched biloma and 3 patients developed both cystic and branched biloma. Percutaneous drainage was applied for 4 patients. One patient underwent partial hepatectomy and one mortality occurred due to progressive biloma and multiple organ failure. Although severe intrahepatic biloma following TACE is rare, the procedure should be performed with caution. Timely and appropriate management, including percutaneous drainage, partial hepatectomy and antibiotic administration should be performed in the case of any signs of infection. [ABSTRACT FROM AUTHOR]

A highly chemoselective three-component cascade reaction among alcohols or thiols, electron-deficient alkenes, and a,ß-unsaturated ketones takes place under the catalysis of triethylamine, providing densely functionalized chain products in 44-99% yields. The transformation presumably proceeds through a sequential cascade of hetero- Michael/Michael reactions. [ABSTRACT FROM AUTHOR]

One strategy for terahertz (THz) detection in GaAs/AlGaAs quantum well photodetectors under the magnetic field is reported. The THz detection begins to operate after the normally empty hydrogenic donor ground states in the AlGaAs barriers become populated by electrons transferred from the GaAs wells. Through the Landau quantization arising from a perpendicular magnetic field, we achieved the electron transfer from subband Landau levels in the GaAs wells at liquid helium temperature when the magnetic field reaches a certain threshold. One detector based on this strategy exhibited a dramatic range of frequency tunability of 3.20-6.13 THz. Our photothermal ionization spectroscopy measurements show quantitative agreement with the theoretical calculation of intradonor transition energies, verifying the origin of the strongly enhanced frequency tunability from the Zeeman behavior of transferred electrons in the AlGaAs barriers. This finding is useful for exploring magneto-optical effects and realization of wide tunability in THz photodetectors. [ABSTRACT FROM AUTHOR]

One strategy for terahertz (THz) detection in GaAs/AlGaAs quantum well photodetectors under the magnetic field is reported. The THz detection begins to operate after the normally empty hydrogenic donor ground states in the AlGaAs barriers become populated by electrons transferred from the GaAs wells. Through the Landau quantization arising from a perpendicular magnetic field, we achieved the electron transfer from subband Landau levels in the GaAs wells at liquid helium temperature when the magnetic field reaches a certain threshold. One detector based on this strategy exhibited a dramatic range of frequency tunability of 3.20-6.13 THz. Our photothermal ionization spectroscopy measurements show quantitative agreement with the theoretical calculation of intradonor transition energies, verifying the origin of the strongly enhanced frequency tunability from the Zeeman behavior of transferred electrons in the AlGaAs barriers. This finding is useful for exploring magneto-optical effects and realization of wide tunability in THz photodetectors. [ABSTRACT FROM AUTHOR]

The solid-liquid method was used to prepare the continuous casting of copper cladding aluminium by liquid aluminum alloy and solid copper, and the interfacial phase formation of Al-Cu bimetal at different pouring temperatures (700, 750, 800 °C) was investigated by means of metallograph, scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) methods. The results showed that the pouring temperature of aluminum melt had an important influence on the element diffusion of Cu from the solid Cu to Al alloy melt and the reactions between Al and Cu, as well as the morphology of the Al-Cu interface. When the pouring temperature was 800 °C, there were abundant Al-Cu intermetallic compounds (IMCs) near the interface. However, a lower pouring temperature (700 °C) resulted in the formation of cavities which was detrimental to the bonding and mechanical properties. Under the conditions in this study, the good metallurgical bonding of Al-Cu was achieved at a pouring temperature of 750 °C. [ABSTRACT FROM AUTHOR]

Signal injection method (SIM) is widely applied to the insulation parameters' measurement in distribution network for its convenience and safety. It can be divided into two kinds of patterns: injecting a specific frequency signal or several frequencies' groups, and scanning frequency in a scheduled frequency scope. In order to avoid the disadvantages in related researches, improved signal injection method (ISIM), in which the frequency characteristic of the transformer magnetizing impedance is taken into consideration, is proposed. In addition, optimization for signal injection position has been accomplished, and the corresponding three calculation methods of line-to-ground capacitance has been derived. Calculations are carried out through the vector information (vector calculation method), the amplitude information (amplitude calculation method), the phase information (phase calculation method) of voltage and current in signal injecting port, respectively. The line-to-ground capacitance is represented by lumped parameter capacitances in high-voltage simulation test. Eight different sinusoidal signals are injected into zero-sequence circuit, and then line-to-ground capacitance is calculated with the above-mentioned vector calculation method based on the voltage and the current data of the injecting port. The results obtained by the vector calculation method show that ISIM has a wider application frequency range compared with signal injection method with rated parameters (RSIM) and SIM. The RSIM is calculated with the rated transformer parameters of magnetizing impedance, and the SIM based on the ideal transformer model, and the relative errors of calculation results of ISIM are smaller than that for other methods in general. The six groups of two-frequency set are chosen in a specific scope which is recommended by vector calculation results. Based on ISIM, the line-to-ground capacitance calculations through the amplitude calculation method and phase calculation method are compared, and then its application frequency range, which can work as a guidance for line-to-ground capacitance measurement, is concluded. [ABSTRACT FROM AUTHOR]

The present study was designed to investigate the role of circulating miRNA-21 (miR-21) in vascular restenosis of lower extremity arterial occlusive disease (LEAOD) patients after interventional therapy. A total of 412 LEAOD patients were enrolled randomly in the present study. According to computed tomography angiography (CTA) and ankle-brachial index (ABI), patients were assigned into the restenosis group and the non-restenosis group. miR-21 expression was detected with quantitative real-time PCR (qRT-PCR) before and after patients underwent interventional therapy. A follow-up period of 6 months was achieved. A receiver operating characteristic (ROC) curve was drawn and the area under the curve (AUC) was calculated to assess the predictive value of miR-21 in vascular restenosis. Patients were older in the restenosis group than in the non-restenosis group. The percentages of patients with diabetes and hypertension were higher in the restenosis group than in the non-restenosis group, and the Fontaine stage exhibited a significant difference between the two groups. miR-21 expression was higher in the restenosis group than in the non-restenosis group. miR-21 expression level was related to age, diabetes and hypertension in the restenosis group. Using miR-21 to predict vascular restenosis yielded an AUC of 0.938 (95% confidence interval (CI): 0.898–0.977), with Youden index of 0.817, sensitivity of 83.5% and specificity of 98.2%. Logistic regression analysis revealed that diabetes and miR-21 expression were the major risk factors for vascular restenosis of LEAOD. miR-21 can be used as a predictive indicator for vascular restenosis of LEAOD after interventional therapy. [ABSTRACT FROM AUTHOR]

Directional modulation (DM) can be achieved based on uniform linear arrays where the maximum spacing between adjacent antennas is half-wavelength of the frequency of interest in order to avoid spatial aliasing. To exploit the additional degrees of freedom provided in the spatial domain, sparse antenna arrays can be employed for more effective DM. In this study, the spare array design problem in the context of DM is formulated from the viewpoint of compressive sensing (CS), so that it can be solved using standard convex optimisation toolboxes in the CS area. In detail, a common set of active antennas needs to be found for all modulation symbols generating a response close to the desired one. The key to the solution is to realise that group sparsity has to be employed, as a common antenna set cannot be guaranteed if the antenna locations are optimised for each modulation symbol individually. Moreover, two practical scenarios are considered for the proposed design: robust design with model errors and design with practical non-zero-sized antennas, and corresponding solutions are found by modifying the proposed standard solution. [ABSTRACT FROM AUTHOR]

Electrostatic interactions play an essential role in many analytical applications including molecular sensing and transport studies using nanopores and separation of charged species. Here, we report the voltammetric quantification of electrostatic ion enrichment in a 5-20 nm thin electrochemical cell. A simple lithographic micro/nanofabrication process was used to create ultrathin-layer cells (UTLCs) with a critical dimension (i.e., cell thickness) as small as 5 nm. The voltammetric response of a UTLC was found to be largely dominated by the electrostatic interaction between charges on the cell walls and the redox species. We show that the ultrasmall cell dimension yielded a 100-300-fold enrichment for cationic redox species. An interesting surface adsorption effect was also demonstrated. [ABSTRACT FROM AUTHOR]

Determination of solid surface free energy is still an open problem. At present, there are two leading theories on how to determine the adhesion of droplets on rough substrates: one theory stresses that the droplet adhesion force lies in the areas of contact and interaction energy between liquid and solid molecules, whereas the other holds that the length of the edge of drops is essential. In this work, we unify the two theories through lattice Boltzmann simulations and demonstrate that the adhesion force could depend on either the contact area or the contact line, depending on the direction of the adhesion force measured, that is, by vertically separating the two materials or laterally sliding the droplet on the substrate. We reveal that for separating droplets away from rough substrates, the vertical adhesion (pull-off) force depends more significantly on the contact area rather than on the contact line. However, for sliding a droplet on substrates, the lateral adhesion force depends on the contact line while being independent of the contact area. [ABSTRACT FROM AUTHOR]

Bamboo materials with improved antibacterial performance based on ZnO and graphene oxide (GO) were fabricated by vacuum impregnation and hydrothermal strategies. The Zn2+ ions and GO nanosheets were firstly infiltrated into the bamboo structure, followed by dehydration and crystallization upon hydrothermal treatment, leading to the formation of ZnO/GO nanocomposites anchored in the bulk bamboo. The bamboo composites were characterized by several techniques including scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and X-ray diffraction (XRD), which confirmed the existence of GO and ZnO in the composites. Antibacterial performances of bamboo samples were evaluated by the bacteriostatic circle method. The introduction of ZnO/GO nanocomposites into bamboo yielded ZnO/GO/bamboo materials which exhibited significant antibacterial activity against Escherichia coli (E. coli, Gram-negative) and Bacillus subtilis (B. subtilis, Gram-positive) bacteria and high thermal stability. The antimicrobial bamboo would be expected to be a promising material for the application in the furniture, decoration, and construction industry. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of Ecklonia kurome extract (EKE) on thyroid hormone concentrations in male mice. Methods: Mice were administered EKE by gastric intubation for 15 days. PTU or L-T4 was set as positive control. Twenty-four hours after the last administration, all animals were sacrificed by cervical dislocation. Blood was collected and serum samples assayed for T3 and T4. Furthermore, the liver was removed for biochemical analysis. Results: T3 and T4 serum levels in mice decreased after the administration of EKE. The relative potency of EKE was calculated in terms of percent increase or decrease in thyroid hormones. Compared with the control value, the decrease in T3 concentration by a high dose of EKE was approximately 64.32%. Compared with the control group, hepatic LPO decreased (p < 0.01) while superoxide dismutase (SOD, p < 0.01) and catalase (CAT, p < 0.01) activities were significantly increased by the high dose of EKE, thus indicating its anti-peroxidative role. Conclusion: This suggests that EKE may be useful for the treatment of hyperthyroidism, but further studies are required to ascertain this. [ABSTRACT FROM AUTHOR]

Heterotrimeric G proteins, which are composed of Gα and Gβγ subunits, transduce signals sensed by the coupled surface receptors. Aberrant expressions of G proteins have been observed in many cancer types. This study aimed to determine the expression level of the stimulatoryGprotein alpha S subunit (Gαs, the main transcript encoded by the GNAS locus) and its biological function in renal cell carcinoma (RCC). Western blotting and quantitative reverse transcription-PCR results show that Gαs expression dramatically increased in RCC cell lines (ACHN, GRC-1, and 786-O) compared to normal renal epithelial cells HK-2. Knockdown of Gαs by small interferingRNA (siRNA) caused a significant inhibition on proliferation of ACHN cells as indicated by MTT assay and colony formation assay. Overexpression of Gαs in HK-2 cells promoted cell proliferation and led to a higher level of intracellular cyclic adenosine monophosphate (cAMP) in response to parathyroid hormone (PTH) compared to the cells transfected with empty vector. Notably, the growth of HK-2 cells overexpressing Gαs was efficiently inhibited in the presence of protein kinase A (PKA) inhibitor H89. Furthermore, in a xenograft model by subcutaneous injection of ACHN cells, tumor growth was also suppressed by H89. Taken together, these results suggest that Gαs plays a tumor-promoting role in RCC and possibly acts through a PKA-dependent pathway. Our findings may provide new clues for target therapy for RCC in the future. [ABSTRACT FROM AUTHOR]

A parallel domain de-composition algorithm for solving an optimal control problem governed by a parabolic partial differential equation is proposed. This algorithm is based upon non-overlapping domain decomposition. In every iteration, the global problem is reduced to solve simultaneously some implicit subproblems on many sub-domains by using explicit flux approximations near inner-boundaries at each timestep. Both a priori error bounds of optimal orders and optimal rates of convergence for the iterative schemes are presented. Numerical experiments are also performed to verified the theoretical analysis. [ABSTRACT FROM AUTHOR]

By utilizing different small amine molecules as structure-affecting agents (SAAs) and charge-balancing agents (CBAs), four new M-Sn-Q (M = Zn, Ag; Q = S, Se) compounds with the anionic architectures ranging from a one-dimensional (1D) chain to a three-dimensional (3D) network have been solvothermally synthesized. Compound [(Me)2NH2]2ZnSn3Se8 (1) features an anionic (4,4) layer of [ZnSn3Se8]n2n- and represents a rare [ZnSn3Se10] T2 cluster-based two-dimensional Zn-Sn-Se compound directed by organic amine. Compound [NH4]3AgSn3Se8 (2) contains infinite linear anionic chains of [AgSn3Se8]n3n-. Compound [CH3NH3]2[H3O]Ag5Sn4Se12·C2H5OH (3) exhibits a 3D open-framework structure of [Ag5Sn4Se12]n3n- with intersecting 3D channels. Compound [CH3NH3]6Ag12Sn6S21 (4) features a 3D framework structure with 1D channels filled by [CH3NH3]+ cations. The most fascinating structural feature of compound 4 is that a complex 3D [Ag12S17]n22n- anionic network exists based on the combination of three types of basic building blocks of [AgS2] dumbbells, [AgS3] triangles, and [AgS4] tetrahedra. The thermal stabilities, optical properties of the title compounds 1-4, as well as the theoretical band structure and density of states of compound 4 have been studied. Moreover, compound 3 displayed visible-light-driven photocatalytic activity for the degradation of crystal violet. [ABSTRACT FROM AUTHOR]

Background: Acetyl-CoA is an important precursor in Saccharomyces cerevisiae. Various approaches have been adopted to improve its cytosolic level previously with the emphasis on engineering the "acetyl-" part of acetyl-CoA. To the best of our knowledge, there have been no reports on engineering the "-CoA" part so far. Results: In this study, we had tried to engineer S. cerevisiae from both the "-CoA" part via pantothenate kinase overexpression (PanK from S. cerevisiae, the rate-limiting enzyme for CoA synthesis) and the "acetyl-"part through PDH bypass introduction (ALD6 from S. cerevisiae and SeAcsL641P from Salmonella enteric). A naringenin-producing reporter strain had been constructed to reflect cytosolic acetyl-CoA level as acetyl-CoA is the precursor of naringenin. It was found that PanK overexpression or PDH bypass introduction alone only led to a twofold or 6.74-fold increase in naringenin titer, but the combination of both (strain CENFPAA01) had resulted in 24.4-fold increase as compared to the control (strain CENF09) in the presence of 0.5 mM substrate p-coumaric acid. The supplement of PanK substrate pantothenate resulted in another 19% increase in naringenin production. Conclusions: To greatly enhance acetyl-CoA level in yeast cytosol, it is feasible to engineer both the "acetyl-" part and the "-CoA" part simultaneously. Insufficient CoA supply might aggravate acetyl-CoA shortage and cause low yield of target product. [ABSTRACT FROM AUTHOR]

Zuojin formula (ZJ) is a traditional Chinese medicine (TCM) prescription consisted of Coptidis Rhizoma (CR) and Euodiae Fructus (EF), and has been used to treat gastrointestinal (GI) disease for more than 700 years. Fan-Zuojin formula (FZJ) is a related TCM prescription also consisted of CR and EF with the opposite proportion. In recent years, ZJ was getting more attention for its antitumor potential, but the indeterminate pharmacokinetic (PK) behavior restricted its clinical applications, and the PK differences between ZJ and FZJ were also largely unknown. Consequently it is necessary to carry out a full-scale PK study to demonstrate the physiological disposition of ZJ, as well as the comparative PK study between ZJ and FZJ to illustrate the compatibility dose effects. Therefore a liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method was established and validated for the determinations of coptisine, epiberberine, palmatine, berberine, 8-oxocoptisine, 8-oxoepiberberine, noroxyhydrastinine, corydaldine, dehydroevodiamine, evodiamine, wuchuyuamide-I, and evocarpine in rat plasma. PK characteristics of 12 alkaloids after oral administration of ZJ and FZJ were compared, and the result was analyzed and discussed with the help of an in silico study. Then an integrated PK study was carried out with the AUC-based weighting method and the total drug concentration method. The established method has been successfully applied to reveal the PK profiles of the 12 alkaloids in rat plasma after oral administration of ZJ and FZJ. The results showed that: (1) double peaks were observed in the plasma concentration-time (C-T) curves of the alkaloids after ZJ administration; but the C-T curves approximately matched the two-compartment model after FZJ administration; (2) There were wide variations in the absorption levels of these alkaloids; and even for a certain alkaloid, the dose modified systemic exposure levels and elimination rate also varied significantly after administration of ZJ and FZJ extracts. The results could be interpreted as follows: firstly, inhibition effect on GI motility caused by the high content CR alkaloids (especially berberine) in ZJ could delay the Tmax, and increase the absorption and systemic exposure levels of the other alkaloids, and also lead to the double peak phenomenon of these alkaloids. However, for quaternary protoberberine alkaloids (QPA), double peaks were primarily caused by the different Ka value in two intestinal absorption sites; Secondly, absorption was the major obstacle to the systemic exposure level of the alkaloids from CR and EF. In silico and PK studies suggested that the absorption of these alkaloids, except QPAs, mainly depended on their solubility rather than permeability; Thirdly, EF could promote the absorption and accelerate the elimination of QPAs, and had a greater influence on the former than the latter. At last the integrated PK analysis suggested that berberine and dehydroevodiamine could be regarded as the representative components to reflect the PK behaviors of CR and EF alkaloids after administration of ZJ and FZJ. In conclusion, the absorption, elimination and systemic exposure level of these alkaloids were mainly influenced by the proportion of EF and CR, the pharmacological effect on GI motility, and the physicochemical property of these alkaloids. These findings would be helpful for a better understanding of the activities and clinical applications of ZJ, FZJ and other related TCM prescriptions. [ABSTRACT FROM AUTHOR]

By acquiring information over a wide area regardless of weather conditions and solar illumination, space-borne Synthetic Aperture Radar (SAR) has the potential to be a promising application for traffic monitoring. However, the backscatter character of a vehicle in a SAR image is unstable and varies with image parameters, such as aspect and incidence angle. To investigate vehicle detectability in SAR images for traffic monitoring applications, images of four common types of vehicles in China were acquired using the fully polarimetric (FP) SAR of Radarsat-2 in our experiments. Methods for measuring a vehicle's aspect angle and backscatter intensity are introduced. The experimental FP SAR images are used to analyze the detectability, which is affected by factors such as vehicle size, vehicle shape, and aspect angle. Moreover, a new metric to improve vehicle detectability in FP SAR images is proposed and compared with the well-known intensity metric. The experimental results show that shape is a crucial factor in affecting the backscatter intensity of vehicles, which also oscillates with varying aspect angle. If the size of a vehicle is smaller than the SAR image resolution, using the intensity metric would result in low detectability. However, it could be improved in an FP SAR image by using the proposed metric. Compared with the intensity metric, the overall detectability is improved from 72% to 90% in our experiments. Therefore, this study indicates that FP SAR images have the ability to detect stationary vehicles on the road and are meaningful for traffic monitoring. [ABSTRACT FROM AUTHOR]

Four novel matrine-based alkaloids (1-4) were isolated from the seeds of Sophora alopecuroides. Compounds 1 and 2 possess unprecedented 6/6/6/4 and 6/5/6/6 ring systems, respectively, while 3 and 4 are a pair of stereoisomeric matrine-acetophenone alkaloids with an unusual skeleton. Their structures were elucidated by means of spectroscopic methods and single-crystal X-ray diffraction. Hypothetical biogenetic pathways for 1-4 are proposed, and their antiviral activities are also discussed. [ABSTRACT FROM AUTHOR]

We investigate a high-efficiency broadband terahertz wave modulator with structures made from the conjugated polymer [2-methoxy-5-(20-ethylhexyloxy)-1, 4-phenylennevinylene], graphene, and Si, irradiated with an external excitation laser. We demonstrate a strategy that can alleviate the tradeoff between the requirements of modulation depth and modulation speed in polymer/silicon terahertz wave modulators. Using terahertz time-domain and continuous-wave systems, we measured both the terahertz transmission modulation properties and the time responses of the modulator structures. The conjugated polymer/graphene/silicon structure achieved a high modulation factor of 93% for transmission as well as improved the modulation speed of the devices based on polymer/silicon. The high modulation efficiency of the polymer/graphene/silicon structure was induced by the enhancement in carrier density and the extremely high carrier mobility of graphene, respectively. [ABSTRACT FROM AUTHOR]

Rho GTPases, including the Rho, Cdc42, Rac, and ROP subfamilies, act as pivotal signaling switches in various growth and developmental processes. Compared with the well-defined role of cytoskeletal organization in Rho signaling, much less is known regarding transcriptional regulation. In a mutant screen for phenotypic enhancers of transgenic Arabidopsis plants expressing a constitutively active form of ROP2 (designated CA1-1), we identified RNA polymerase II (Pol II) C-terminal domain (CTD) phosphatase-like 1 (CPL1) as a transcriptional regulator of ROP2 signaling. We show that ROP2 activation inhibits CPL1 activity by promoting its degradation, leading to an increase in CTD Ser5 and Ser2 phosphorylation. We also observed similar modulation of CTD phosphorylation by yeast Cdc42 GTPase and enhanced degradation of the yeast CTD phosphatase Fcp1 by activated ROP2 signaling. Taken together, our results suggest that modulation of the Pol II CTD code by Rho GTPase signaling represents an evolutionarily conserved mechanism in both unicellular and multicellular eukaryotes. [ABSTRACT FROM AUTHOR]

Recent laboratory tests and field observations have revealed that unsaturated sands are susceptible to liquefaction. Systematic investigation of liquefaction potential of unsaturated sands is, however, lacking. In this paper, a coupled hydromechanical elastoplastic constitutive model for unsaturated sands is calibrated using available laboratory test results. A parametric study is then conducted using the calibrated constitutive model to investigate the effects of initial degree of saturation, relative density, and effective confining pressure on the liquefaction resistance of unsaturated sands. The results suggest that the liquefaction resistance of unsaturated sands increases with decreasing degree of saturation and increasing relative density and effective confining pressure. The results also reveal that the effect of degree of saturation on liquefaction resistance is more pronounced near 100% degree of saturation. The results of the parametric study are then condensed to create a design chart that can be used for liquefaction potential evaluation of unsaturated sands. The degree of saturation, relative density, and effective confining pressure are taken into account in this design chart. [ABSTRACT FROM AUTHOR]

The sodium salt roasting process was widely used for extracting vanadium due to its high yield rate of vanadium. However, the serious pollution was a problem. The calcium roasting process was environmentally friendly, but the yield rate of vanadium was relatively lower. Focusing on the calcium metavanadate produced in the calcium roasting process of vanadium minerals, the mechanism of the carbonate leaching for calcium metavanadate and its leaching kinetics of calcium metavanadate were studied. With the increase of the leaching agent content, the decrease of the particle size, the increase of the temperature and the increase of the reaction time, the leaching rate of vanadium increased, and the constant of reaction rate increased. In the carbonate leaching process, the calcium carbonate was globular and attached to the surface of calcium metavanadate. In the solution containing bicarbonate radical, lots of cracks formed in the dissolution process. However, the cracks were relatively fewer in the solution containing carbonate. In the present study, the carbonate leaching for calcium metavanadate was controlled by diffusion, the activation energy reached maximum and minimum in the sodium bicarbonate and the sodium carbonate solution, respectively. The activation energy value in the ammonium bicarbonate solution was between those two solutions. The kinetic equations of the carbonate leaching for calcium metavanadate were as follows: 1 - 2/3η - (1 - η)2/3 = 4.39[Na2CO3]0.75/r0 × exp(-2527.06/T)t; 1 - 2/3η - (1 - η)2/3 = 7.89[NaHCO3]0.53/r0 × exp(-2530.67/T)t; 1 - 2/3η - (1 - η)2/3 = 6.78[NH4HCO3]0.69/r0 × exp(-2459.71/T)t. [ABSTRACT FROM AUTHOR]

Conspectus: Metal nanoparticles are key electrode materials in a variety of electrochemical applications including basic electron-transfer study, electrochemical sensing, and electrochemical surface enhanced Raman spectroscopy (SERS). Metal nanoparticles have also been extensively applied to electrocatalytic processes in recent years due to their high catalytic activity and large surface areas. Because the catalytic activity of metal nanoparticle is often highly dependent on their size, shape, surface ligands, and so forth, methods for examining and better understanding the correlation between particle structure and function are of great utility in the development of more efficient catalytic systems. Despite considerable progress in this field, the understanding of the structure–activity relationships remains challenging in nanoparticle-based electrochemistry and electrocatalysis due to limitations associated with traditional ensemble measurements. One of the major issues is the ensemble averaging of the electrocatalytic response which occurs over a very large number of nanoparticles of various sizes and shapes. Additionally, the electrochemical response can also be greatly affected by properties of the ensemble itself, such as the particle spacing. The ability to directly measure kinetics of electrochemical reactions at structurally well-characterized single nanoparticles opens up new possibilities in many important areas including nanoscale electrochemistry, electrochemical sensing, and nanoparticle electrocatalysis. When a macroscopic electrode is placed in a solution containing redox molecules and metal nanoparticles, random collision and adsorption of nanoparticles occurs at the electrode surface in addition to redox reactions when a suitable potential is present on the electrode. In a special case where particles are catalytically more active than the substrate, the faradaic signals can be greatly amplified on particle surfaces and a steady shift in the baseline current would be expected due to many particles adsorbing on the electrode. Single particle events can be temporally resolved when an ultramicroelectrode (UME) is used as the recording electrode. The use of an UME not only reduces the collision frequency, but also greatly decreases baseline noise, thereby resulting in clear resolution of single collision events. Single particle collision has quickly grown into a popular electroanalytical technique in recent years. Alternatively, one can use nanoelectrodes to immobilize single nanoparticles so that they can be individually studied in electrochemistry and electrocatalysis. Nanoparticle immobilization also allows one to obtain detailed structural information on the same particles and offers enormous potential for developing more comprehensive understanding of the structure–function relationship in nanoparticle-based electrocatalysts. This Account summarizes recent electrochemical experiments of single metal nanoparticles which have been performed by our group using both of these schemes. [ABSTRACT FROM AUTHOR]

Background: High-mobility group protein box1 (HMGB1) is a pivotal factor in the development and progression of many types of tumor. Its role in hepatocellular carcinoma (HCC), and especially its correlation with intratumoral and peritumoral macrophage infiltration, remains obscure. We analyzed the potential roles and prognostic value of HMGB1 and explored the correlation between HMGB1 and macrophage infiltration in HCC using clinical samples. Methods: We reviewed clinicopathological and follow-up data on a cohort of 149 patients with HCC complicated with Hepatitis B-related cirrhosis. We measured the expression of HMGB1 and CD68 in tumoral and peritumoral liver tissues after curative resection and assessed the impacts of the tumor-associated macrophage (TAM) count and HMGB1 expression on clinicopathologic characteristics, overall survival (OS), and recurrence-free survival (RFS). Results: Ninety-four of the patients had elevated tumoral HMGB1 expression and 59 of the patients had elevated peritumoral HMGB1 expression, compared to only 4 patients with elevated peritumoral HMGB1 expression in 36 pateints with Hepatitis B virus (HBV)-negative HCC without liver cirrhosis (p < 0.001). The peritumoral HMGB1 expression levels were correlated with tumor invasiveness, BCLC stage, and recurrence. The degree of TAM infiltration was higher in peritumoral tissues with high HMGB1 expression than in peritumoral tissues with low HMGB1 expression (p < 0.001). There was no significant difference in TAM infiltration between tumoral tissues with high and low HMGB1 expression. Kaplan-Meier analysis showed that intratumoral HMGB1 overexpression was associated with poor OS, but not with RFS. High peritumoral HMGB1expression and TAM count, which correlated positively with tumor size and BCLC stage, were independent prognostic factors for OS (p < 0.001 and p = 0.017, respectively) and RFS (p = 0.002 and p = 0.024, respectively). Multivariate analyses indicated peritumoral HMGB1 expression (p = 0.014) and TAM count (p = 0.037), as well as tumor differentiation (p = 0.026), to be independent significant prognostic factors for RFS. Conclusions: High HMGB1 expression in peritumoral liver tissues correlated with peritumoral macrophage infiltration and had prognostic value in HCC, suggesting that peritumoral HMGB1 might show promise as a new biomarker to predict HCC progression. [ABSTRACT FROM AUTHOR]

Ischemia/reperfusion (I/R) injury can occur during small-for-size liver transplantation, resulting in delayed graft function and decreased long-term graft survival. The aim of the present study was to evaluate the effects of genetic overexpression of endothelial nitric oxide synthase (eNOS) in protecting hepatocytes against I/R injury in a rat model of small-for-size liver transplantation. L02 liver cells were transfected with the eNOS gene using an adenovirus (Ad-eNOS). eNOS expression was detected using quantitative polymerase chain reaction and western blot analysis. To evaluate the effect of eNOS overexpression, L02 cells were placed in a hypoxic environment for 12 h and immediately transferred to an oxygen-enriched atmosphere. For in vivo testing, rats pretreated with Ad-eNOS or control underwent small-for-size liver transplantation. At 6 h after reperfusion, the bile quantity, serum transaminase and nitric oxide (NO) levels, and histological outcomes were evaluated. Cell apoptosis was assessed by flow cytometry or TUNEL assay. In vitro, Ad-eNOS prevented apoptosis in L02 cells with an increase in the level of NO in culture supernatant. In vivo, Ad-eNOS pre-treatment significantly increased bile production, improved abnormal transaminase levels, diminished apoptosis among liver cells, and decreased hepatocellular damage at 6 h after I/R injury. The eNOS-mediated renal protective effects might be associated with the downregulation of tumor necrosis factor-α and a reduction in macrophage activation in the early stage of reperfusion in small-for-size liver allografts. eNOS-derived NO production significantly attenuates hepatic I/R injury. Thus, eNOS overexpression constitutes a promising therapeutic approach to prevent liver I/R injury following small-for-size liver transplantation. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate the possibility of boosting action recognition performance by exploiting the associated scene context. Towards this end, the authors model a scene as a mid-level 'middle layer' in order to bridge action descriptors and action categories. This is achieved via a scene topic model, in which hybrid visual descriptors, including spatial- temporal action features and scene descriptors, are first extracted from a video sequence. Then, the authors learn a joint probability distribution between scene and action using a naive Bayes nearest neighbour algorithm, which is adopted to jointly infer the action categories online by combining off-the-shelf action recognition algorithms. The authors demonstrate the advantages of their approach by comparing it with state-of-the-art approaches using several action recognition benchmarks. [ABSTRACT FROM AUTHOR]

Commercial tomatoes are widely perceived by consumers as lacking flavor. A major part of that problem is a postharvest handling system that chills fruit. Low-temperature storage is widely used to slow ripening and reduce decay. However, chilling results in loss of flavor. Flavor-associated volatiles are sensitive to temperatures below 12 °C, and their loss greatly reduces flavor quality. Here, we provide a comprehensive view of the effects of chilling on flavor and volatiles associated with consumer liking. Reduced levels of specific volatiles are associated with significant reductions in transcripts encoding key volatile synthesis enzymes. Although expression of some genes critical to volatile synthesis recovers after a return to 20 °C, some genes do not. RNAs encoding transcription factors essential for ripening, including RIPENING INHIBITOR (RIN), NONRIPENING, and COLORLESS NONRIPENING are reduced in response to chilling and may be responsible for reduced transcript levels in many downstream genes during chilling. Those reductions are accompanied by major changes in the methylation status of promoters, including RIN. Methylation changes are transient and may contribute to the fidelity of gene expression required to provide maximal beneficial environmental response with minimal tangential influence on broader fruit developmental biology. [ABSTRACT FROM AUTHOR]

One new pentacyclic triterpenoid, 3β-carboxylicfilic-4(23)-ene (1), and three known pentacyclic triterpenoids, adian-5-en-3α-ol (2), fernenol (3), and fern-7-en-3β-ol (4) were isolated from the petroleum ether phase of the ethanolic extract of Ainsliaea yunnanensis Franch. Their structures were established by spectroscopic methods including 1-D and 2-D NMR, and MS experiments. Compounds 1, 2, 3, and 4 showed significant selective cytotoxicity against human acute monocytic leukemia cell line (THP-1) with IC50 values of 5.12 μM, 1.78 μM, 1.74 μM, and 1.75 μΜ, respectively. Compound 1 also showed an anti-inflammatory effect through the inhibition of the activity of NF-κB by blocking the nuclear translocation of p65. [ABSTRACT FROM AUTHOR]

Cancer cachexia remains a leading cause of morbidity and mortality worldwide, despite extensive research and clinical trials. The prominent clinical feature of cancer cachexia is the continuous loss of skeletal muscle that cannot be fully reversed by conventional nutritional support, and that leads to progressive functional impairment. The mechanism underlying muscle loss in patients with cachexia is poorly understood. The present study analyzed 21 cancer patients with or without cachexia, and demonstrated that mitofusin-2 (Mfn2) was downregulated in the rectus abdominis of patients with cachexia, which was associated with body weight loss. In vitro cell experiments indicated that loss of Mfn2 was associated with atrophy of the C2C12 mouse myoblast cell line. Furthermore, in vivo animal experiments demonstrated that cachexia decreased gastrocnemius muscle mass and Mfn2 expression, and overexpression of Mfn2 in gastrocnemius muscle was able to partially attenuate cachexia-induced gastrocnemius muscle loss. The results of the present study suggested that Mfn2 is involved in cachexia-induced muscle loss and may serve as a potential target for therapy of cachexia. [ABSTRACT FROM AUTHOR]

Water splitting is widely considered to be a promising strategy for clean and efficient energy production. In this paper, for the first time we report an in situ growth of iron-nickel nitride nanostructures on surface-redox-etching Ni foam (FeNi3N/NF) as a bifunctional electrocatalyst for overall water splitting. This method does not require a specially added nickel precursor nor an oxidizing agent, but achieves well-dispersed iron-nickel nitride nanostructures that are grown directly on the nickel foam surface. The commercial Ni foam in this work not only acts as a substrate but also serves as a slow-releasing nickel precursor that is induced by redox-etching of Fe3+. FeCl2 is a more preferable iron precursor than FeCl3 for no matter quality of FeNi3N growth or its electrocatalytic behaviors. The obtained FeNi3N/NF exhibits extraordinarily high activities for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) with low overpotentials of 202 and 75 mV at 10 mA cm-2, Tafel slopes of 40 and 98 mV dec-1, respectively. In addition, the presented FeNi3N/NF catalyst has an extremely good durability, reflecting in more than 400 h of consistent galvanostatic electrolysis without any visible voltage elevation. [ABSTRACT FROM AUTHOR]

Three novel sesquiterpenoid-based meroterpenoids, drychampones A-C (1-3, respectively), were isolated from Dryopteris championii. Compounds 1 and 3 possessed a novel carbon skeleton which was constructed by an 11/6/6 ring system coupled with a pyronone moiety, and 1-3 were three racemates. Their structures and absolute configurations were elucidated by NMR, MS, and computational methods. The hypothetical biosynthetic pathways of these meroterpenoids and their antibacterial activities were also discussed. [ABSTRACT FROM AUTHOR]

The synthesis and reactivity of a series of mononuclear nonheme iron complexes that carry out intramolecular aromatic C-F hydroxylation reactions is reported. The key intermediate prior to C-F hydroxylation, [FeIV(O)(...)](BF4)2 (1-O, Ar1 = -2,6-difluorophenyl), was characterized by single-crystal X-ray diffraction. The crystal structure revealed a nonbonding C-H⋯O=Fe interaction with a CH3CN molecule. Variable-field Mössbauer spectroscopy of 1-O indicates an intermediate-spin (S = 1) ground state. The Mössbauer parameters for 1-O include an unusually small quadrupole splitting for a triplet FeIV(O) and are reproduced well by density functional theory calculations. With the aim of investigating the initial step for C-F hydroxylation, two new ligands were synthesized, ... (L2, Ar2 = -2,6-difluoro-4-methoxyphenyl) and ... (L3, Ar3 = -2,6-difluoro-3-methoxyphenyl), with -OMe substituents in the meta or ortho/para positions with respect to the C-F bonds. FeII complexes [Fe(...)(CH3CN)](ClO4)2 (2) and [Fe(...)(CH3CN)](ClO4)2 (3) reacted with isopropyl 2-iodoxybenzoate to give the C-F hydroxylated FeIII-OAr products. The FeIV(O) intermediates 2-O and 3-O were trapped at low temperature and characterized. Complex 2-O displayed a C-F hydroxylation rate similar to that of 1-O. In contrast, the kinetics (via stopped-flow UV-vis) for complex 3-O displayed a significant rate enhancement for C-F hydroxylation. Eyring analysis revealed the activation barriers for the C-F hydroxylation reaction for the three complexes, consistent with the observed difference in reactivity. A terminal FeII(OH) complex (4) was prepared independently to investigate the possibility of a nucleophilic aromatic substitution pathway, but the stability of 4 rules out this mechanism. Taken together the data fully support an electrophilic C-F hydroxylation mechanism. [ABSTRACT FROM AUTHOR]

This work investigates the anisotropic PEC performances of ZnO single-crystalline (SC) photoanodes and the effect of internal electrostatic fields on the separation of photogenerated charge carriers during PEC water splitting. It was found that the internal electrostatic field can greatly influence the bulk charge separation efficiencies during PEC water splitting depending on its orientations, which can only be promoted as the internal electrostatic field in accordance with the direction of the holes' transportation. Due to the surface stabilization of ZnO polar surfaces, the internal electrostatic field would be gradually decreased to zero near the surface of ZnO SC photoanodes. Therefore, the interfacial charge separation would be mainly determined by the interfacial electric fields in the space charge region formed by the equilibration of the Fermi levels between ZnO and the electrolyte solution. However, the differences on the bulk charge separation efficiencies of ZnO SC photoanodes are much larger than that at the interface, which indicated the bulk charge separation could play a more important role on determining the overall charge separation during PEC water splitting. Therefore, the anisotropic PEC performances of ZnO SC photoanodes during PEC water splitting could be mainly attributed to the internal electrostatic fields. With the assistance of the internal electrostatic field, O-SCs yield a record high solar to hydrogen conversion efficiency of 0.78% at 0.7 V vs RHE and a maximum photocurrent density of 1.84 mA cm-2 at 1.23 V vs RHE with ηb and ηi of 91.6 and 99.5%, respectively. The results demonstrate the effectiveness of internal electrostatic fields in polar single crystals on promoting the bulk charge separation during PEC water splitting, and indicate that polar single crystals could be good candidates to fabricate high efficient PEC photoanodes with high conversion efficiencies. [ABSTRACT FROM AUTHOR]

We report direct observation of electrochemical and thermal dealloying processes of individual metal alloy nanoparticles (NPs). Electrochemical dealloying of single Ag-Hg alloy NPs was achieved in a basic solution (e.g., pH 13) by oxidizing Hg under controlled potentials. Ag can also be oxidized during single-particle collision. However, it requires elevated potentials. The strong basic environment promoted the formation of metal oxides during collision leading to a unique core-shell type nanostructure which was further confirmed by transmission electron microscopy (TEM). In thermal dealloying, Hg was evaporated due to the use of a high-energy electron beam and the process was imaged in situ inside a TEM. Both electrochemical and thermal dealloying processes resulted in the transformation of an amorphous NP to a more stable Ag-Hg alloy nanocrystal. This work demonstrates that NP collision can be a useful tool to study dealloying processes of various nanomaterials at a single-particle level. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRs) regulate the proliferation and metastasis of numerous cancer cell types. It was previously reported that miR-143 levels were downregulated in non-small cell lung cancer (NSCLC) tissues and cell lines, and that the migration and invasion of NSCLC cells was inhibited upon suppression of cell proliferation and colony formation by the upregulation of miR-143. Epidermal growth factor receptor (EGFR), which is a vital factor in the promotion of cancer cell proliferation and has been investigated as a potential focus in cancer therapy, has been reported to be a possible target of miR-143. The present study aimed to investigate the role of miR-143 in NSCLC using NSCLC cell lines and primary cells from NSCLC patients. NSCLC cells were co-transfected with EGFR and miR-143, and the mRNA and protein expression of EGFR were analyzed. Furthermore, the activity of the transfected cancer cells with regard to colony formation, migration, invasion and apoptosis were evaluated. The levels of miR-143 were decreased in the NSCLC cell lines and primary cells from patients with NSCLC compared with the controls. Following transfection with miR-143, the ability of NSCLC cells to proliferate, form colonies, migrate and invade was inhibited. Similarly, knockdown of EGFR led to the suppression of NSCLC cell proliferation. The mRNA and protein expression levels of EGFR were signiicantly reduced following miR-143 overexpression, and the level of miR-143 was inversely correlated with that of EGFR in NSCLC cells. The results of the present study demonstrated that miR-143 was able to suppress NSCLC cell proliferation and invasion by inhibiting the effects of EGFR, suggesting that EGFR may be considered a potential target for NSCLC therapy. [ABSTRACT FROM AUTHOR]

Iron is generally regarded as an unavoidable impurity in Al-Si casting alloys. The acicular Al3Fe and β-Al5FeSi (or Al9Si2Fe2) are common iron-containing intermetallic compounds (IMCs) in conventional structure which have a detrimental impact on the mechanical properties. In this paper, ultrasonic field (USF) was applied to modify acicular iron phases in Al-12%Si-2%Fe and Al-2%Fe alloys. The results show that the USF applied to Al-Fe alloys caused the morphological transformation of both primary and eutectic Al3Fe from acicular to blocky and granular without changes in their composition. In the case of Al-Si-Fe alloys, ultrasonic treatment led to both morphological and compositional conversion of the ternary iron IMCs. When the USF was applied, the acicular β-Al9Si2Fe2 was substituted by star-like α-Al12Si2Fe3. The modification rate of both binary and ternary iron IMCs relates to the USF treatment duration. The undercooling induced by the ultrasonic vibration contributes to the nucleation of intermetallics and can explain the transformation effect. [ABSTRACT FROM AUTHOR]

Aging is a major risk factor in many forms of late-onset neurodegenerative disorders. The ability to recapitulate age-related characteristics of human neurons in culture will offer unprecedented opportunities to study the biological processes underlying neuronal aging. Here, we show that using a recently demonstrated microRNA-based cellular reprogramming approach, human fibroblasts from postnatal to near centenarian donors can be efficiently converted into neurons that maintain multiple age-associated signatures. Application of an epigenetic biomarker of aging (referred to as epigenetic clock) to DNA methylation data revealed that the epigenetic ages of fibroblasts were highly correlated with corresponding age estimates of reprogrammed neurons. Transcriptome and microRNA profiles reveal genes differentially expressed between young and old neurons. Further analyses of oxidative stress, DNA damage and telomere length exhibit the retention of age-associated cellular properties in converted neurons from corresponding fibroblasts. Our results collectively demonstrate the maintenance of age after neuronal conversion. [ABSTRACT FROM AUTHOR]

Neuroligins are postsynaptic cell-adhesion molecules that contribute to synapse specification. However, many other postsynaptic celladhesion molecules are known and the relative contributions of neuroligins versus other such molecules in different types of synapses and neurons remains largely unknown. Here, we have studied the role of neuroligins in cerebellar stellate interneurons that participate in a well defined circuit that converges on Purkinje cells as the major output neurons of cerebellar cortex. By crossing triple conditional knock-out (cKO) mice targeting all three major neuroligins [neuroligin-1 to neuroligin-3 (NL123)] with parvalbumin-Cre (PV-Cre) transgenic mice, we deleted neuroligins from inhibitory cerebellar interneurons and Purkinje cells, allowing us to study the effects of neuroligin deletions on cerebellar stellate cell synapses by electrophysiology in acute slices. PV-Cre/NL123 cKO mice did not exhibit gross alterations of cerebellar structure or cerebellar interneuron morphology. Strikingly, electrophysiological recordings in stellate cells from these PV-Cre/NL123 cKO mice revealed a large decrease in NMDAR-mediated excitatory synaptic responses, which, in stellate cells, are largely extrasynaptic, without a change in AMPA-receptor-mediated responses. Parallel analyses in PV-Cre/NL1 mice that are single NL1 cKO mice uncovered the same phenotype, demonstrating that NL1 is responsible for recruiting extrasynaptic NMDARs. Moreover, we observed only a modest impairment in inhibitory synaptic responses in stellate cells lacking NL123 despite a nearly complete suppression of inhibitory synaptic transmission in Purkinje cells by the same genetic manipulation. Our results suggest that, unlike other types of neurons investigated, neuroligins are selectively essential in cerebellar stellate interneurons for enabling the function of extrasynaptic NMDARs. [ABSTRACT FROM AUTHOR]