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In this paper, based on the feasible method and sensors for the full-scale prestressed monitor, the novel optical fiber sensors and the traditional monitoring sensors will be set up into two prestressed concrete beams with the same geometrical dimensions, material properties, and construction conditions, etc. to investigate the working state of the novel sensors and obtain the evolution law of prestress loss of the prestressed feature component under the static load. The results show that the evolution law of prestress loss of the loaded beam under the condition of no damage state and initial crack is the same as the non-loaded one; however, the prestress loss increases with the increase of time under the situation with the limit crack. The total loss of the prestressed beam with the limit crack is 36.4% without damage. The prestress loss of the prestressed beam under the static load increase with the development of the crack (injury). [ABSTRACT FROM AUTHOR]

Along with the promotion of China's green development strategy and the policy of financial services to the real economy, how financialization affects corporate green innovation becomes an urgent issue to be explored. Using Chinese A-share listed enterprises from 2007 to 2020, this study empirically analyzes the impact of financialization on corporate green innovation and its underlying mechanism, and the moderating effect of heterogeneous environmental regulation is examined. Results show that financialization significantly inhibits corporate green innovation, and the command-and-control environmental regulation is more effective in weakening the inhibiting effect of financialization on corporate green innovation than market-incentivized and public-participation environmental regulation. Moreover, mechanism analyses show that financialization inhibits corporate green innovation mainly by affecting innovation input and financing constraints. Extended analyses show that the inhibiting effects of financialization on strategic and substantive green innovation of enterprises are not significantly different, but the inhibiting effect of financialization on independent green innovation is significantly higher than that on joint green innovation. In addition, the inhibiting effect of financialization on green innovation is more significant in non-heavy polluting industries and regions with high regulatory pressure. This study reveals the negative effects of financialization on corporate green innovation from a micro-finance perspective, which not only helps to improve the internal investment decisionmaking mechanism of companies and the regulatory system of corporate financialization, but also has some insights to guide the practice of green innovation of real enterprises and promote the green transformation of economic development mode. [ABSTRACT FROM AUTHOR]

In recent years, the influence of earthquake on geotechnical engineering has been paid more and more attention, and the study of soil dynamic characteristics is the most important part. In order to reveal the dynamic characteristics of the silty clay in the reservoir area of the hydropower station, firstly many samples are taken for dry-wet cycle several times to simulate the changes of soil in the reservoir slope under the condition of reservoir water level change or rainfall evaporation. And then dynamic triaxial tests are carried out on those samples to determine the dynamic deformation development law of the soil. The model is established based on Gompertz curve, making it be applied to the deformation curve of soil dynamics. The dynamic deformation curve of samples after different times of dry-wet cycle is fitted. The error of fitting value and actual value is within 5 %, and the relationship between vibration frequency and dynamic strain is established. The research results have practical significance for the prediction of dynamic deformation of soil and the application of Gompertz curve. [ABSTRACT FROM AUTHOR]

• The meso-numerical model, corresponding to the realistic aggregate distribution, was established. • The spatial distribution of the coarse aggregate determines the meso-mechanical properties of concrete and then affects the macro-mechanical behavior. • To reduce the cracking risk of concrete, the volume fraction and gradation of aggregate should be kept within an appropriate range. In this study, the aggregate information in concrete was extracted by Digital Image Processing (DIP) technology, and the two-dimension three-phase (coarse aggregate, mortar, and interface transition zone) meso-numerical model corresponding to the realistic aggregate distribution was established. Based on the model, considering the effects of coarse aggregate distribution, volume fraction and size on the fracture behavior, the fracture test and numerical simulation of four-point shear beams with notches under mixed-mode I-II stress were carried out. The results showed that the concrete meso -numerical model based on real aggregate can accurately reflect the meso-scale fracture process of concrete, and cracks always develop along the weak interface transition zone. It is the aggregate in the fracture trend zone that makes the fracture path tortuous, and the bending and shearing stress around the aggregate will change substantially. Moreover, the external force work of numerical model increases with the increase of aggregate volume fraction and maximum aggregate size, and the dissipated energy of coarse aggregate with small particle size increases with the rise in its proportion in gradation. Especially, the spatial distribution of the coarse aggregate determines the meso-mechanical properties of concrete and then affects the macro-mechanical behavior. To reduce the cracking risk of concrete, the volume fraction and gradation of aggregate should be kept within an appropriate range. [ABSTRACT FROM AUTHOR]

We have studied the scattering process of AlGaAs/GaAs two-dimensional electron gas with the nearby embedded GaSb/GaAs type-II quantum dots (QDs) at low temperature. Quantum Hall effect and Shubnikov–de Haas oscillation were performed to measure the electron density n2D, the transport lifetime τt, and the quantum lifetime τq under various biased gate voltage. By comparing measured results of QDs sample with that of reference sample without embedded QDs, mobilities (transport mobility μt and quantum mobility μq) dominated by GaSb QDs scattering were extracted as functions of n2D. It was found that the ratios of τt to τq were varying within the range of 1–4, implying the scattering mechanism belonging to the sort of short-range interaction. In the framework of Born approximation, a scattering model considering rectangular-shaped potential with constant barrier height was successfully applied to explain the transport experimental data. In addition, an oscillating ratio of τt/τq with the increasing n2D was predicted in the model. [ABSTRACT FROM AUTHOR]

Various diseases, including cancers, age-associated disorders, and acute liver failure, have been linked to the oncogene, MYC. Animal testing and clinical trials have shown that sustained tumor volume reduction can be achieved when MYC is inactivated, and different combinations of therapeutic agents including MYC inhibitors are currently being developed. In this review, we first provide a summary of the multiple biological functions of the MYC oncoprotein in cancer treatment, highlighting that the equilibrium points of the MYC/MAX, MIZ1/MYC/MAX, and MAD (MNT)/MAX complexes have further potential in cancer treatment that could be used to restrain MYC oncogene expression and its functions in tumorigenesis. We also discuss the multifunctional capacity of MYC in various cellular cancer processes, including its influences on immune response, metabolism, cell cycle, apoptosis, autophagy, pyroptosis, metastasis, angiogenesis, multidrug resistance, and intestinal flora. Moreover, we summarize the MYC therapy patent landscape and emphasize the potential of MYC as a druggable target, using herbal medicine modulators. Finally, we describe pending challenges and future perspectives in biomedical research, involving the development of therapeutic approaches to modulate MYC or its targeted genes. Patients with cancers driven by MYC signaling may benefit from therapies targeting these pathways, which could delay cancerous growth and recover antitumor immune responses. [ABSTRACT FROM AUTHOR]

Highlights • The random generation and distribution of aggregate gradation, location and shape in concrete beam were realized. • The size of the specimen has influence on the peak load value in I–II mixed-mode fracture behavior of concrete. • The propagation path has no obvious relation with the content of the aggregate, and closely related with the loading pattern in concrete. Abstract The fracture and damage behaviors of concrete under I–II mixed-mode loading are of great importance in determining the failure mode of concrete material and structure. In this paper, the four-point bending beams with different aggregate volume contents have been fabricated and tested to obtain the limited loading capacities, and the Digital Image Correlation (DIC) method was utilized for monitoring the local displacement above the notch during the loading procedure. Furthermore, based on the aggregate occupation and translation algorithm, a modified random aggregate model has been proposed for generating the four-point bending beam with precast notch, and the numerical simulations for the four-point bending beam with different aggregate volume contents and depths have been proceed. [ABSTRACT FROM AUTHOR]

Water vapor adsorption and desorption isotherms and kinetics studies on three Sichuan Basin shale samples were performed at 298 K by an accurate gravimetric method. The adsorption equilibrium data were fitted using both Dent model and Modified Dent model to estimate the adsorption characteristic of water on the primary and secondary sites. The primary site adsorption is restricted to a monolayer while the secondary site adsorption is associated with multilayer sorption. A positive correlation was found between clay mineral content and monolayer sorption content. The isosteric heats of sorption of water were determined from the equilibrium data and they decreased with the increase of adsorption amount. The adsorption/desorption hysteresis were studied with the pore structure. The kinetics of water vapor adsorption was studied with the unipore model and linear driving force mass transfer (LDF) model. The effective diffusivity and kinetic rate constant varied with the increase of relative pressure, which suggested diffusion of water vapor on shale corresponding to a combination of adsorption on primary sites, adsorption on secondary sites, formation of water clusters, and capillary condensation. [ABSTRACT FROM AUTHOR]

Alkyl ketene dimer (AKD) is commonly applied as oil-in-water emulsions in the papermaking industry. Herein a particle stabilized AKD emulsion was developed to avoid the adverse effect of surfactant, further improving the sizing performance and reducing the hydrolysis of AKD emulsions, where layered double hydroxide (LDH) particles were employed as a stabilizer of the AKD emulsions after being modified with glutamic acid (Glu). The success of the modification of LDH with Glu was evidenced by high-resolution transmission electron microscopy (HRTEM), zeta potential, Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) studies. Furthermore, the impact of the modification on the wettability of LDH was analyzed. It was found that the hydrophilic LDH particles became partially hydrophobic after being modified with Glu (at 1.5 mmol/g) and, thus, promoted the formation of emulsions with fine and uniform droplets that resisted creaming/coalescence formation. The adsorption of the Glu-modified LDH particles on the AKD droplet surface improved the emulsion stability, which was verified by fluorescent confocal laser scanning microscopy. Meanwhile, by using Glu-modified LDH nanoparticles, the storage stability of AKD emulsion and its sizing performance on paper were also improved. [ABSTRACT FROM AUTHOR]

Exosomes are extracellular vesicles with a 30-150 nm diameter originating from endosomes. In recent years, scientists have regarded exosomes as an ideal small molecule carrier for the targeted treatment of Alzheimer's disease (AD) across the blood-brain barrier due to their nanoscale size and low immunogenicity. A large amount of evidence shows that exosomes are rich in biomarkers, and it has been found that the changes in biomarker content in blood, cerebrospinal fluid, and urine are often associated with the onset of AD patients. In this paper, some recent advances in the use of exosomes in the treatment of AD are reviewed, and various exosome markers and some latest detection methods are summarized to provide some evidence for the detection or treatment of AD by exosomes. [ABSTRACT FROM AUTHOR]

The up-regulation of ALL1-fused gene from chromosome 1q (AF1q) is commonly seen in aggressive hematologic malignancies as well as in several solid tumor tissues. However, its expression and intrinsic function in human colorectal cancer (CRC) remains largely undefined. To explore the role of AF1q in human CRC progression, AF1q expression was analyzed in human CRC tissue samples and CRC cell lines. Clinical specimens revealed that AF1q was up-regulated in human CRC tissues, and that this up-regulation was associated with tumor metastasis and late tumor, lymph node, metastasis (TNM) stage. AF1q knockdown by shRNA inhibited tumor cell proliferation, migration, invasion, and epithelial-mesenchymal transition in vitro, as well as tumorigenesis and liver metastasis in vivo, whereas these effects were reversed following AF1q overexpression. These AF1q-mediated effects were modulated by the protein kinase B (AKT) signaling pathway, and inhibition of AKT signaling attenuated AF1q-induced tumor promotion. Thus, AF1q contributes to CRC tumorigenesis and progression through the activation of the AKT signaling pathway. AF1q might therefore serve as a promising new target in the treatment of CRC. [ABSTRACT FROM AUTHOR]

The widespread use of thermoelectric conversion technology requires thermoelectric materials of high thermoelectric efficiency and high fracture strength. Single crystal SnSe shows an extremely high zT value in the moderate temperature range, but its mechanical properties have rarely been studied so far. Here we use density functional theory to determine the ideal strength and deformation mechanism of perfect SnSe single crystals for shear deformations. The lowest ideal strength of SnSe is found to be 0.59 GPa under the (100)/⟨001⟩ shear load, which agrees with experimental evidence that single crystals cleave along the (100) slip plane. The van der Waals-like Se-Sn bond, which couples the different Se-Sn layered substructures, is much softer than the covalent Se-Sn bond which constructs the Se-Sn layered substructure. This creates pathways of easy slip between Se-Sn layered substructures, which can release shear stress and lead to structural failure. Meanwhile, the layered substructures themselves can resist shearing within the (100)/⟨001⟩ slip system. These results provide a plausible atomic explanation for understanding the intrinsic mechanics of SnSe. [ABSTRACT FROM AUTHOR]

A hailstorm forecast method is proposed in the paper. Edge Detect Cellular Neural Network (EDCNN) method is used to extract the edge of cloud radar images. We have detected the texture of the cloud images. Then the texture image has been processed with wavelet transform. The hail data information from the image has been found. We will get approximate detail coefficients, level detail coefficients, vertical detail coefficients, diagonal detail coefficients, and reconstructed coefficients. Construct hail cloud life feature vector matrix to explain the problem. Found the corresponding rules through the five coefficients. At last, through the simulation experiment achieve the purpose of hail forecast. A feature vector of hail cloud life has been constructed, the rules of hail had been found from the feature vector. And Compared with the contour variance of the hail cloud inner and outer, we will find this paper puts forward the method is more effective. The conclusion is rationality according the simulation experiment verifies. [ABSTRACT FROM AUTHOR]

This paper extends the classical two-regime threshold autoregressive model by introducing hysteresis to its regime-switching structure, which leads to a new model: the hysteretic autoregressive model. The proposed model enjoys the piecewise linear structure of a threshold model but has a more flexible regime switching mechanism. A sufficient condition is given for geometric ergodicity. Conditional least squares estimation is discussed, and the asymptotic distributions of its estimators and information criteria for model selection are derived. Simulation results and an example support the model. [ABSTRACT FROM AUTHOR]

Background: Extrahepatic Cholangiocarcinoma (EHCC) is one of the uncommon malignancies in the digestive system which is characterized by a poor prognosis. Aberrations of miRNAs have been shown involved in the progression of this disease. In this study, we evaluated the expression and effects of miR-34a on EHCC. Methods: miR-34a expression levels were detected in EHCC tissues, adjacent non-tumor tissues, normal bile duct (NBD) specimens of patients and cholangiocarcinoma (CC) cell lines by quantitative real-time polymerase chain reaction (qRT-PCR). Relationships between miR-34a with clinical characteristics of EHCC patients were further analyzed. Computational search, functional luciferase assay and western blot were further used to demonstrate the downstream target of miR-34a in CC cells. Immunohistochemistry was carried on to identify the downstream target gene of miR-34a in EHCC patients. Cell morphology, invasion and migration assays were further applied to confirm the anti-carcinogenic effects of miR-34a through the downstream target. Results: miR-34a expression was significantly decreased in human EHCC tissues and CC cell lines when compared with the adjacent non-tumor tissues and normal bile duct tissues. miR-34a was found correlated with the migration and invasion in EHCC patients. Smad4 was over-expressed in most of the EHCC patients and was further demonstrated as one of the downstream targets of miR-34a, which was involved in the progression of EHCC. Moreover, activation of miR-34a suppressed invasion and migration through TGF-beta/Smad4 signaling pathway by epithelial-mesenchymal transition (EMT) in vitro. Conclusions: Taken together, our results suggest that miR-34a inhibits invasion and migration by targeting Smad4 to suppress EMT through TGF- beta/Smad signaling pathway in human EHCC. [ABSTRACT FROM AUTHOR]

A dehydrogenative Heck annelation reaction of indolizine with diaryl acetylene via dual C-H bond cleavage was developed. Oxygen gas was employed as a clean oxidant in this catalysis under base-free conditions. Diarylpyrrolo[2,1,5-cd]indolizines were synthesized with high atom economy. In addition, kinetic isotope experiments provided evidence for C-H bond metalation of the 5-position of the indolizine as the rate-limiting step. [ABSTRACT FROM AUTHOR]

Farnesoid X receptor (FXR, Nr1h4) is a ligand-activated transcription factor belonging to the nuclear receptor superfamily. FXR is essential in maintaining bile acid (BA) homeostasis, and FXR-/- mice develop cholestasis, inflammation, and spontaneous liver tumors. The signal transducer and activator of transcription 3 (STAT3) is well known to regulate liver growth, and STAT3 is feedback inhibited by its target gene, the suppressor of cytokine signaling 3 (SOCS3). Strong activation of STAT3 was detected in FXR-/- mouse livers. However, the mechanism of STAT3 activation with FXR deficiency remains elusive. Wild-type (WT) and FXR-/- mice were used to detect STAT3 pathway activation in the liver. In vivo BA feeding or deprivation was used to determine the role of BAs in STAT3 activation, and in vitro molecular approaches were used to determine the direct transcriptional regulation of SOCS3 by FXR. STAT3 was activated in FXR-/- but not WT mice. BA feeding increased, but deprivation by cholestyramine reduced, serum inflammatory markers and STAT3 activation. Furthermore, the Socs3 gene was determined as a direct FXR target gene. The elevated BAs and inflammation, along with reduced SOCS3, collectively contribute to the activation of the STAT3 signaling pathway in the liver of FXR-/- mice. This study suggests that the constitutive activation of STAT3 may be a mechanism of liver carcinogenesis in FXR-/- mice. [ABSTRACT FROM AUTHOR]

A novel sensor was developed based on the combination of photonic crystal templating and molecular imprinting technique (MIT) for the detection of simetryn in tobacco samples. The molecularly imprinted photonic crystal hydrogels (MIPHs) was prepared with methacrylic acid (MAA) as monomers, ethylene glycol dimethylacrylate (EGDMA) as cross-linkers, simetryn as imprinting template molecules and polystyrene (PS) microspheres as photonic crystal template. The ordered three-dimensional macro-porous structure of MIPHs with simetryn imprinting template can generate Bragg diffraction, showing a bright structural color. The results show that the MIPHs have high selectivity and excellent sensing performance and can be used for the detection of simetryn from actual tobacco samples. Among the four triazine herbicides with similar structure, MIPHs only produced obvious Bragg diffraction peak wavelength change to simetryn, and MIPHs have good recoverability with four cycle times. When the concentration of simetryn in the actual tobacco increased from 0 to 1.0 μg/mL, the wavelength was red-shifted from 457 nm to 499 nm, which was in the blue and green visible light wavelength range. This new sensor is expected to be used to directly detect pesticide residues in tobacco. • The molecularly imprinted photonic crystal hydrogels (MIPHs) can convert molecular recognition signals into optical signals. • MIPHs recognize simetryn to produce color changes (from green to orange). • MIPHs have highly specific selectivity and recoverability. • MIPHs can identify simetryn pesticide residues in tobacco. [ABSTRACT FROM AUTHOR]

Farnesoid X receptor (FXR) is a nuclear receptor and a key regulator of liver cholesterol and triglyceride homeostasis. Scavenger receptor class B type I (SR-BI) is critical for reverse cholesterol transport (RCT) by transporting high-density lipoprotein (HDL) into liver. FXR induces SR-BI, however, the underlying molecular mechanism of this induction is not known. The current study confirmed induction of SR-BI mRNA by activated FXR in mouse livers, a human hepatoma cell line, and primary human hepatocytes. Genome-wide FXR binding analysis in mouse livers identified 4 putative FXR response elements in the form of inverse repeat separated by one nucleotide (IR1) at the first intron and 1 IR1 at the downstream of the mouse Sr-bi gene. ChIPqPCR analysis revealed FXR binding to only the intronic IR1s, but not the downstream one. Luciferase assays and site-directed mutagenesis further showed that 3 out of 4 IR1s were able to activate gene transcription. A 16-week high-fat diet (HFD) feeding in mice increased hepatic Sr-bi gene expression in a FXR-dependent manner. In addition, FXR bound to the 3 bona fide IR1s in vivo, which was increased following HFD feeding. Serum total and HDL cholesterol levels were increased in FXR knockout mice fed the HFD, compared to wild-type mice. In conclusion, the Sr-bi/SR-BI gene is confirmed as a FXR target gene in both mice and humans, and at least in mice, induction of Sr-bi by FXR is via binding to intronic IR1s. This study suggests that FXR may serve as a promising molecular target for increasing reverse cholesterol transport. [ABSTRACT FROM AUTHOR]

Dyslipidemia is a common metabolic disorder in diabetes. Nitric oxide (NO) production from endothelium plays the primary role in endothelium-mediated vascular relaxation and other endothelial functions. Therefore, we investigated the effects of elevated free fatty acids (FFA) on the stimulation of NO production by phospholipase C (PLC)-activating receptor agonists (potent physiological endothelium-dependent vasodilators) and defined the possible alterations of signaling pathways implicated in this scenario. Exposure of bovine aortic endothelial cells (BAECs) to high concentrations of a mixture of fatty acids (oleate and palmitate) for 5 or 10 days significantly reduced NO production evoked by receptor agonists (bradykinin or ATP) in a time- and dose-dependent manner. Such defects were not associated with alterations of either endothelial NO synthase mass or inositol phospholipid contents but were probably due to reduced elevations of intracellular free Ca2+ levels ([2+]i) under these conditions. Exposure of BAECs to FFA significantly attenuated agonist-induced [2+]i increases by up to 54% in a dose- and time-dependent manner. Moreover, bradykinin receptor affinity on the cell surface was significantly decreased by high concentrations of FFA. The morphology of BAECs was altered after 10-day culture with high FFA. Co-culture with protein kinase C (PKC) inhibitors or antioxidants was able to reverse the impairments of receptor agonist-induced NO production and [2+]i rises as well as the alteration of receptor affinity in BAECs exposed to FFA. These data indicate that chronic exposure to high FFA reduces NO generation in endothelial cells probably by impairing PLC-mediated 2+ signaling pathway through activation of PKC and excess generation of oxidants. [ABSTRACT FROM AUTHOR]

Target-based metabolomics, focused on a subset of metabolites representative of key pathways, is a valuable tool for assessing metabolic changes resulting from genetic mutation, altered gene expression, and protein dysfunction in a given disease state or as a consequence of an environmental perturbation, such as a pharmaceutical. However, simultaneously analyzing hundreds of endogenous metabolites presents a challenge because of their diverse chemical structures and properties. In this study, we report a high-throughput, sensitive, and reproducible method for target-based metabolomics studies. It combines different separation conditions, optimal ionization polarities, and the most sensitive triple-quadrupole MSbased data acquisition mode (MRM). In 10 mm, 205 endogenous metabolites, divided into three subgroups (amino acids, sugar and nucleic acids, and organic acids), are sequentially analyzed on a LC/MS/MRM system. Low picogram sensitivity is achieved for more than half of the metabolites. A 3-4 order of linearity and assay coefficient of variation less than 15% are observed for ∼80% of the metabolites. hi summary, we have established a multiplex LC/MS/MRM method for quantitatively profiling hundreds of known metabolites from complex biological samples. The methodology is generally applicable and easily expandable to include more endogenous or drug metabolites. [ABSTRACT FROM AUTHOR]

Background: SELDI-TOF-MS (Surface Enhanced Laser Desorption/Ionization-Time of Flight-Mass Spectrometry) has become an attractive approach for cancer biomarker discovery due to its ability to resolve low mass proteins and high-throughput capability. However, the analytes from mass spectrometry are described only by their mass-to-charge ratio (m/z) values without further identification and annotation. To discover potential biomarkers for early diagnosis of osteosarcoma, we designed an integrative workflow combining data sets from both SELDI-TOF-MS and gene microarray analysis. Methods: After extracting the information for potential biomarkers from SELDI data and microarray analysis, their associations were further inferred by link-test to identify biomarkers that could likely be used for diagnosis. Immuno-blot analysis was then performed to examine whether the expression of the putative biomarkers were indeed altered in serum from patients with osteosarcoma. Results: Six differentially expressed protein peaks with strong statistical significances were detected by SELDI-TOF-MS. Four of the proteins were up-regulated and two of them were down-regulated. Microarray analysis showed that, compared with an osteoblastic cell line, the expression of 653 genes was changed more than 2 folds in three osteosarcoma cell lines. While expression of 310 genes was increased, expression of the other 343 genes was decreased. The two sets of biomarkers candidates were combined by the link-test statistics, indicating that 13 genes were potential biomarkers for early diagnosis of osteosarcoma. Among these genes, cytochrome c1 (CYC-1) was selected for further experimental validation. Conclusion: Link-test on datasets from both SELDI-TOF-MS and microarray high-throughput analysis can accelerate the identification of tumor biomarkers. The result confirmed that CYC-1 may be a promising biomarker for early diagnosis of osteosarcoma. [ABSTRACT FROM AUTHOR]

The recent paper by Peng & Yao (2003) gave an interesting extension of least absolute deviation estimation to generalised autoregressive conditional heteroscedasticity, GARCH, time series models. The asymptotic distributions of absolute residual autocorrelations and squared residual autocorrelations from the GARCH model estimated by the least absolute deviation method are derived in this paper. These results lead to two useful diagnostic tools which can be used to check whether or not a GARCH model fitted by using the least absolute deviation method is adequate. Some simulation experiments give further support to the asymptotic theory and a real data example is also reported. [ABSTRACT FROM AUTHOR]

Force-field-(FF)-based molecular simulation is essential but challenging in the theoretical research of complex thermoelectric (TE) materials. As they are general and crucial in TE semiconductors, the structural natures of anharmonicity and anisotropy can help us understand the inherent relation between thermal and mechanical behavior, and therefore the reliability of FF studies can be assessed. In this paper, given prior knowledge of the structural, mechanical and thermal properties as well as the limitations and necessary approximations of the FF method, a feasible and detailed FF modeling scheme and simulation has been designed for Bi2Te3, which is a typical high-performance TE material. Using the complementary approach combining quasi-harmonic lattice and molecular dynamics, the obtained potential is systematically confirmed to be accurate and efficient for the prediction of anharmonic and anisotropic behavior in thermotics and mechanics over a wide temperature range compared with the present Bi2Te3 models. This reveals that the intrinsic anisotropy and anharmonicity can measure the asymmetry of crystal lattices and the interatomic force in the current state. In addition, the significant distinction of temperature-dependent anharmonic effects in different directions of Bi2Te3 stems from its layered hierarchical structure, in which weak van der Waals bonding will probably be the key structural factor in comprehensively improving performance for mass production and wearable application. This prior-knowledge-based FF study is also suggested as a bridge between the theoretical understanding of micro-mechanisms and the experimental measurement of TE material properties, leading to a general framework of molecular simulation for other complex energy materials. [ABSTRACT FROM AUTHOR]

Sulfonamides (SAs) in agricultural soils can be degraded in rhizosphere, but can also be taken up by vegetables, which thereby poses human health and ecological risks. A glasshouse experiment was conducted using multi-interlayer rhizoboxes to investigate the fate of three SAs in rape and hot pepper rhizosphere soil systems to examine the relationship between the accumulation and their physicochemical processes. SAs mainly entered pepper shoots in which the accumulation ranged from 0.40 to 30.64mg kg-1, while SAs were found at high levels in rape roots ranged from 3.01 to 16.62mg kg-1. The BCFpepper shoot exhibited a strong positive linear relationship with log Dow, while such relationship was not observed between other bioconcentration factors (BCFs) and log Dow. Other than lipophilicity, the dissociation of SAs may also influence the uptake and translocation process. Larger TF and positive correlation with log Dow indicate preferential translocation of pepper SAs. There was a significant (p < 0.05) dissipation gradient of SAs observed away from the vegetable roots. In addition, pepper could uptake more SAs under solo exposure, while rape accumulated more SAs under combined exposure. When SAs applied in mixture, competition between SAs might occur to influence the translocation and dissipation patterns of SAs. [ABSTRACT FROM AUTHOR]

The conversion efficiency (zT) of thermoelectric (TE) materials has been enhanced over the last two decades, but their engineering applications are hindered by the poor mechanical properties, especially the low strength at working conditions. Here we used density functional theory (DFT) to show a strength enhancement in the TE semiconductor InSb arising from the twin boundaries (TBs). This strengthening effect leads to an 11% enhancement of the ideal shear strength in flawless crystalline InSb where this theoretical strength is considered as an upper bound on the attainable strength for a realistic material. DFT calculations reveal that the directional covalent bond rearrangements at the TB accommodating the structural mismatch lead to the anisotropic resistance against the deformation combined with the enhanced TB rigidity. This produces a strong stress response in the nanotwinned InSb. This work provides a fundamental insight for understanding the deformation mechanism of nanotwinned TE semiconductors, which is beneficial for developing reliable TE devices. [ABSTRACT FROM AUTHOR]

Monoclinic gallium oxide (β-Ga2O3) has important applications in power devices and deep UV optoelectronic devices because of such novel properties as a wide band gap, high breakdown electric field, and a wide range of n-type doping conductivity. However, the intrinsic failure mechanisms of β-Ga2O3 remain unknown, which limits the fabrication and packaging of β-Ga2O3-based electronic devices. Here we used density-functional theory at the Perdew-Burke-Ernzerhof level to examine the shear-induced failure mechanisms of β-Ga2O3 along various plausible slip systems. We found that the (001)/⟨010⟩ slip system has the lowest ideal shear strength of 3.8 GPa among five plausible slip systems, suggesting that (001)/⟨010⟩ is the most plausible activated slip system. This slip leads to an intrinsic failure mechanism arising from breaking the longest Ga-O bond between octahedral Ga and fourfold-coordinated O. Then we identified the same failure mechanism of β-Ga2O3 under biaxial shear deformation that mimics indentation stress conditions. Finally, the general stacking fault energy (SFE) surface is calculated for the (001) surface from which we concluded that there is no intrinsic stacking fault structure for β-Ga2O3. The deformation modes and SFE calculations are essential to understand the intrinsic mechanical processes of this semiconductor material, which provides insightful guidance for designing high-performance semiconductor devices. [ABSTRACT FROM AUTHOR]

Bismuth telluride (Bi2Te3) based thermoelectric (TE) materials have been commercialized successfully as solid-state power generators, but their low mechanical strength suggests that these materials may not be reliable for long-term use in TE devices. Here we use density functional theory to show that the ideal shear strength of Bi2Te3 can be significantly enhanced up to 215% by imposing nanoscale twins. We reveal that the origin of the low strength in single crystalline Bi2Te3 is the weak van der Waals interaction between the Te1 coupling two Te1-Bi-Te2-Bi-Te1 five-layer quint substructures. However, we demonstrate here a surprising result that forming twin boundaries between the Te1 atoms of adjacent quints greatly strengthens the interaction between them, leading to a tripling of the ideal shear strength in nanotwinned Bi2Te3 (0.6 GPa) compared to that in the single crystalline material (0.19 GPa). This grain boundary engineering strategy opens a new pathway for designing robust Bi2Te3 TE semiconductors for high-performance TE devices. [ABSTRACT FROM AUTHOR]

Lanthanum telluride (La3Te4) is an n-type high-performance thermoelectric material in the high temperature range, but its mechanical properties remain unknown. Since we want robust mechanical properties for their integration into industrial applications, we report here quantum mechanics (QM) simulations to determine the ideal strength and deformation mechanisms of La3Te4 under pure shear deformations. Among all plausible shear deformation paths, we find that shearing along the (0 0 1)/ slip system has the lowest ideal shear strength of 0.99 GPa, making it the most likely slip system to be activated under pressure. We find that the long range La–Te ionic interactions play the predominant role in resisting shear deformation. To enhance the mechanical strength, we suggest improving the long ionic La–Te bond stiffness to strengthen the ionic La–Te framework in La3Te4 by a defect-engineering strategy, such as partial substitution of La by Ce or Pr having isotypic crystal structures. This work provides the fundamental information to understand the intrinsic mechanics of La3Te4. [ABSTRACT FROM AUTHOR]

This paper proposes a parameter design method for multi-element resonant converters (MERCs) with a unique resonant zero point (RZP). This method is mainly composed of four steps. These steps include program filtration, loss comparison, 3D figure fine-tuning and priority compromise. It features easy implementation, effectiveness and universal applicability for almost all of the existing RZP-MERCs. Meanwhile, other design methods are always exclusive for a specific topology. In addition, a novel dual-CTL converter is also proposed here. It belongs to the RZP-MERC family and is designed in detail to explain the process of parameter selection. The performance of the proposed method is verified experimentally on a 500W prototype. The obtained results indicate that with the selected parameters, an extensive dc voltage gain is obtained. It also possesses over-current protection and minimal switching loss. The designed converter achieves high efficiencies among wide load ranges, and the peak efficiency reaches 96.9%. [ABSTRACT FROM AUTHOR]

β-Galactosidase (β-gal) is an important biomarker for ovarian cancers. In this work, we designed and synthesized a novel iridium(III)-based probe 1 for discriminating ovarian carcinoma cell lines from normal cell lines. The probe could detect β-gal even in the presence of a highly autofluorescent background. The probe also showed a good linear response to β-gal between 0 and 30 U/mL, with a detection limit of 0.51 U/mL. Importantly, complex 1 could selectively "light up" ovarian carcinoma cells, while exhibiting negligible luminescence in normal cells. Overall, complex 1 could be potentially used as a useful probe for detecting β-gal expression in the context of ovarian cancer diagnostics. [ABSTRACT FROM AUTHOR]

We consider a unified least absolute deviation estimator for stationary and nonstationary fractionally integrated autoregressive moving average models with conditional heteroscedasticity. Its asymptotic normality is established when the second moments of errors and innovations are finite. Several other alternative estimators are also discussed and are shown to be less efficient and less robust than the proposed approach. A diagnostic tool, consisting of two portmanteau tests, is designed to check whether or not the estimated models are adequate. The simulation experiments give further support to our model and the results for the absolute returns of the Dow Jones Industrial Average Index daily closing price demonstrate their usefulness in modelling time series exhibiting the features of long memory, conditional heteroscedasticity and heavy tails. [ABSTRACT FROM AUTHOR]

Farnesoid X receptor (FXR) belongs to the nuclear receptor superfamily with its endogenous ligands bile acids. Mice with whole body FXR deficiency develop liver tumors spontaneously, but the underlying mechanism is unclear. Moreover, it is unknown whether FXR deficiency in liver alone serves as a tumor initiator or promoter during liver carcinogenesis. This study aims to evaluate the effects of hepatocyte-specific FXR deficiency (FXRhep-/-) in liver tumor formation. The results showed that FXRhep-/- mice did not show spontaneous liver tumorigenesis with aging (up to 24 mo of age). Therefore FXRhep-/- mice were fed a bile acid (cholic acid)-containing diet alone or along with a liver tumor initiator, diethylnitrosamine (DEN). Thirty weeks later, no tumors were found in wild-type or FXRhep-/- mice without any treatment or with DEN only. However, with cholic acid, while only some wild-type mice developed tumors, all FXRhep-/- mice presented with severe liver injury and tumors. Interestingly, FXRhep-/- mouse livers increased basal expression of tumor suppressor p53 protein, apoptosis, and decreased basal cyclin D1 expression, which may prevent tumor development in FXRhep-/- mice. However, cholic acid feeding reversed these effects in FXRhep-/- mice, which is associated with an increased cyclin D1 and decreased cell cycle inhibitors. More in-depth analysis indicates that the increased in cell growth might result from disturbance of the MAPK and JAK/Stat3 signaling pathways. In conclusion, this study shows that hepatic FXR deficiency may only serve as a tumor initiator, and increased bile acids is required for tumor formation likely by promoting cell proliferation. [ABSTRACT FROM AUTHOR]

The synergistic effect of a highly active surface/interface and an optimized electronic structure of electrocatalysts is of great significance to improve the performance of the hydrogen evolution reaction. Herein, a superhydrophilic core@shell heterostructure nanorod-integrated electrode composed of an amorphous VOx nanoshell (3-7 nm) and a crystalline Ni3S2 core supported on Ni foam (CS--NS/NF) was prepared by an in situ conversion method. We prove that the amorphous VOx not only helps to kinetically decouple the adsorption/dissociation of hydroxyl/water, but also enriches the active sites, thereby significantly enhancing the electron transfer efficiency and electrocatalytic activity toward the hydrogen evolution reaction (HER). The optimized CS--NS/NF has excellent hydrogen production performance, with overpotentials of 335 and 394 mV at current densities of 500 and 1000 mA cm-2, respectively, as well as superior durability for over 68 h in 1 M KOH. [ABSTRACT FROM AUTHOR]

Five polyamine fixing agents with different molecular weights but slightly different charge densities were used to treat a deinked pulp. Their efficacy in controlling colloidal substances (CS) in the pulp was measured using focused beam reflectance measurements (FBRM). The objective was to determine if the colloidal substances were affected by the fixing agents by a "colloidal fixation" mechanism, i.e., colloidal particles being fixed onto pulp fiber in an un-agglomerated, singleparticle state, or a "colloidal agglomeration" one, i.e., colloidal particles being coagulated by fixing agents into bigger agglomerates. The results showed that colloidal fixation does take place, especially for the polyamine with the smallest molecular weight. Among the five polyamines, it was found that higher molecular weights tended to result in more extensive colloidal agglomeration, but the effect of charge density was almost insignificant. Because it is efficient in differentiating between these two fixation mechanisms, FBRM is a powerful tool in screening different fixing agents. [ABSTRACT FROM AUTHOR]

TiAlSiN coatings were deposited on TC6 substrates by high power impulse magnetron sputtering at various bias voltages for the improvement of titanium alloy anti-sand erosion performance. The effect of bias voltage on the composition, microstructure and mechanical properties were investigated by X-ray photoelectron spectroscopy, X-ray diffractometer, transmission electron microscopy, scanning electron microscopy, Rockwell-C indentation, scratch testing and nano nanoindentation. The erosion performance was evaluated at the impingent angles of 30° and 90° respectively in a sand blasting tester. With the application and increase in bias voltage, the discharge current increases from ∼87 A to ∼210 A. The coatings exhibit face center cubic structure, mainly composed of the (Ti,Al)N nanocrystallites and Si 3 N 4 matrix. The preferred orientation shifts from (200) to (220) in the range of 0∼−150 V, but goes back to (200) at −200 V. The surface nodular defects and deposition rate are gradually reduced, yet the sectional structure becomes much denser. The residual stress is compressive and continually grows, whereas the adhesion strength, hardness (H), Young's modulus (E) and H/E ratio gradually increase before decreasing, arriving at maximum values of ∼68 N, ∼37.53 GPa, ∼339.9 GPa and 0.11 respectively at −150 V. The erosion resistance of the TiAlSiN coatings is consistent with these mechanical changes at various bias voltages and is also optimal at −150 V, which is ∼14 times that of TC6 substrate. The failure mechanism comes from coating brittleness nature, fractured chips and microcracks, regardless sand erosion angles, yet the driving forces are different. • The erosion resistance of TiAlSiN coatings is consistent of the variation of their mechanical properties with bias voltages. • The composite TiAlSiN coatings with optimal erosion resistance is deposited at −150 V in HiPIMS. • Surface nodule defects seriously deteriorate the erosion damage. • The erosion mechanisms of coatings are from their brittle nature, fractured chips and microcracks, regardless sand erosion angles. • The microcracks are more apt to appear at the hard coating with low toughness. [ABSTRACT FROM AUTHOR]

Chronic high glucose (HG) inflicts glucotoxicity on vulnerable cell types such as pancreatic β cells and contributes to insulin resistance and impaired insulin secretion in diabetic patients. To identify HG-induced cellular aberrations that are candidate mediators of glucotoxicity in pancreatic b cells, we analyzed gene expression in ERoSHK6, a mouse insulin-secreting cell line after chronic HG exposure (six-day exposure to 33.3 mM glucose). Chronic HG exposure which reduced glucose-stimulated insulin secretion (GSIS) increased transcript levels of 185 genes that clustered primarily in 5 processes namely cellular growth and proliferation; cell death; cellular assembly and organization; cell morphology; and cell-to-cell signaling and interaction. The former two were validated by increased apoptosis of ERoSHK6 cells after chronic HG exposure and reaffirmed the vulnerability of β cells to glucotoxicity. The three remaining processes were partially substantiated by changes in cellular morphology and structure, and instigated an investigation of the cytoskeleton and cell-cell adhesion. These studies revealed a depolymerized actin cytoskeleton that lacked actin stress fibers anchored at vinculin-containing focal adhesion sites as well as loss of E-cadherin-mediated cell-cell adherence after exposure to chronic HG, and were concomitant with constitutive ERK1/2 phosphorylation that was refractory to serum and glucose deprivation. Although inhibition of ERK phosphorylation by PD98059 promoted actin polymerization, it increased apoptosis and GSIS impairment. These findings suggest that ERK phosphorylation is a proximate regulator of cellular processes targeted by chronic HG-induced gene expression and that dynamic actin polymerization and depolymerization is important in β cell survival and function. Therefore, chronic HG alters gene expression and signal transduction to predispose the cytoskeleton towards apoptosis and GSIS impairment. [ABSTRACT FROM AUTHOR]

Background: Farnesoid X Receptor (FXR) is a member of the nuclear receptor superfamily and is a ligand-activated transcription factor essential for maintaining liver and intestinal homeostasis. FXR is protective against carcinogenesis and inflammation in liver and intestine as demonstrated by the development of inflammation and tumors in the liver and intestine of FXR knock- out mice. However, mechanisms for the protective effects of FXR are not completely understood. This study reports a novel role of FXR in regulating expression of Sqstm1, which encodes for p62 protein. p62 plays an important role in maintaining cellular homeostasis through selective autophagy and activating signal transduction pathways, such as NF-κB to support cell survival and caspase-8 to initiate apoptosis. FXR regulation of Sqstm1 may serve as a protective mechanism. Methods and Results: This study showed that FXR bound to the Sqstm1 gene in both mouse livers and ileums as determined by chromatin immunoprecipitation. In addition, FXR activation enhanced transcriptional activation of Sqstm1 in vitro. However, wild-type mice treated with GW4064, a synthetic FXR ligand, showed that FXR activation induced mRNA and protein expression of Sqstm1/p62 in ileum, but not in liver. Interestingly, FXR- transgenic mice showed induced mRNA expression of Sqstm1 in both liver and ileum compared to wild-type mice. Conclusions:Our current study has identified a novel role of FXR in regulating the expression of p62, a key factor in protein degradation and cell signaling. Regulation of p62 by FXR indicates tissue- specific and gene-dosage effects. Furthermore, FXR-mediated induction of p62 may implicate a protective mechanism of FXR. [ABSTRACT FROM AUTHOR]

Macrophages play an important role in the pathogenesis of systemic lupus erythematosus-associated diffuse alveolar hemorrhage (DAH). The immunomodulation of macrophage responses might be a potential approach for the prevention and treatment of DAH. Erythropoietin (EPO) could regulate macrophage bioactivities by binding to the EPO receptor expressing on macrophages. This study assessed the effects of EPO on DAH protection using an immune-mediated DAH murine model with macrophages as the major contributor. A DAH murine model was established in female C57BL/6 mice by an i.p. injection of pristane. We found that EPO administration alleviates DAH by reducing pulmonary macrophages recruitment and promoting phenotype switch toward M2 macrophages in vivo. EPO drove macrophages to the anti-inflammatory phenotype in the primary murine bone marrow-derived macrophages and macrophages cell line RAW 264.7 with LPS, IFN-γ, and IL-4 in vitro. Moreover, EPO treatment increases the expression of EPOR and decreases the expression of miR-494-3p, resulting in increased phosphorylation of JAK2 and STAT3. In conclusion, EPO can be a potential therapeutic agent in DAH by reducing cell apoptosis and regulating macrophage polarization through the EPOR/JAK2/STAT3 axis. Further studies are also needed to validate the direct target of miR-494-3p in regulating JAK2/STAT3 signaling transduction. [ABSTRACT FROM AUTHOR]

For the composite glass box girder, the generalized Bayesian objective function of elastic constants of the structure was derived based on layered shell element theory. Mechanical performances of the composite glass box girder were solved by layered shell element method. Combined with quadratic parabolic interpolation search scheme of optimized step length, the adaptive Powell's optimization theory was taken to complete the stochastic identification of elastic constants of composite glass box girder. Then the adaptive Powell's identification steps of elastic constants of the structure were presented in detail and the adaptive Powell's identification procedure was accomplished. From some classic examples, it is finally achieved that the adaptive Powell's identification of elastic constants of composite glass box girder has perfect convergence and numerical stability, which testifies that the adaptive Powell's identification theory of elastic constants of composite glass box girder is correct and reliable. The stochastic characteristics of systematic responses and elastic constants are well deliberated in generalized Bayesian objective function. And in iterative processes, the adaptive Powell's identification is irrelevant with the complicated partial differentiation of the systematic responses from the layered shell element model to the elastic constants, which proves high computation efficiency. [ABSTRACT FROM AUTHOR]

The article discusses that both stereochemical environment and oxidation state of single cobalt active sites in cobalt tetraaminophthalocyanine are tuned via molecular engineering with 2,5-di-tert-butyl-1,4-benzoquinone (DTBBQ); and mentions that single cobalt active sites on the ultrathin conjugated microporous polymer (CMP) nanosheets exhibit unprecedentedly high activity and excellent stability under mild reaction conditions.

Aristolochia pseudoutriformis X.X.Zhu & J.S.Ma, sp. nov. and A. yangii X.X.Zhu & J.S.Ma, sp. nov., two new species from Yunnan, China, are described and illustrated here. The former is morphologically similar to A. utriformis and A. forrestiana and the latter is similar to A. cucurbitoides and A. forrestiana. According to Ma's (1989a) classification, both new species belong to Aristolochia subgenus Siphisia on the basis of the 3-lobed gynostemium and oblong anthers that are adnate in pairs, opposite the gynostemium lobes. Meanwhile, the two new species are assessed as Vulnerable (VU D2) according to IUCN Red List criteria. [ABSTRACT FROM AUTHOR]

Pressure variations during fluid transients in pipelines are of significant interest to hydraulic engineers and scientists. To clarify the effects of unsteady wall shear stress on the propagation of pressure waves, we re-examine an analytical solution that was recently developed with unsteady wall shear stress included. Physical insights about the effects of unsteady wall shear stress are obtained. Comparisons of the solution with available experimental data and the numerical results of an instantaneous-acceleration-based model are carried out. It is found that unsteady wall shear stress can cause both the amplitude decay and phase shifts of the water hammer pressure. The phase shifts caused by unsteady wall shear stress are indicated by the deformation of pressure variations. Furthermore, we highlight that for initial-laminar and low-Reynolds-number flow conditions, the effect of unsteady wall shear stress is independent of the initial Reynolds number but is related to another dimensionless parameter that has a clear physical significance; that is, the ratio of viscosity diffusion time to the period of water hammer or the ratio of boundary layer thickness to the pipe radius. [ABSTRACT FROM AUTHOR]

The cellular senescence-inhibited gene (CSIG) is implicated in important biological processes, including cellular senescence and apoptosis. Our work showed that CSIG is involved in the myristoylation of the serine/threonine protein phosphatase PPM1A. Previous research has shown that myristoylation is necessary for PPM1A to dephosphorylate Smad2 and Smad3. However, the control and the biological significance of the myristoylation remain poorly understood. In this study, we found that CSIG knockdown disturbs PPM1A myristoylation and reduces the dephosphorylation by PPM1A of its substrate Smad2. By regulating PPM1A myristoylation, CSIG is involved in modulating the signaling of transforming growth factor β (TGF-β). Further study of the mechanism indicated that CSIG facilitates the interaction between N-myristoyltransferase 1 (NMT1) and PPM1A. Taking the data together, we found that CSIG is a regulator of PPM1A myristoylation and TGF-β signaling. By promoting the myristoylation of PPM1A, CSIG enhanced the phosphatase activity of PPM1A and further inhibited TGF-β signaling. This work not only extends the biological significance of CSIG but also provides new ideas and a reference for the study of the regulatory mechanism of myristoylation. [ABSTRACT FROM AUTHOR]

Background Restoring the normal joint line (JL) is an important goal to achieve in total knee arthroplasty (TKA). We intended to study the veracity of several landmarks used to level the normal JL in Chinese people. Methods Two hundred fifteen standard CT scans of knee joint were included to measure the distances from landmarks to distal JL (DJL) and posterior JL (PJL), along with femoral width (FW) in order to calculate the ratios. Landmarks included adductor tubercle (AT), medial epicondyle (ME), lateral epicondyle (LE), tibial tubercle (TT), fibular head (FH) and the inferior pole of the patella (IPP). Ratios were calculated between distances and FW (e.g. FHDJL/FW). Linear regression analysis and t test were used to determine the accuracy and the differences amongst sides of the leg, genders and races. Results The average of IPPDJL/FW, TTDJL/FW, FHDJL/FW, LEDJL/FW, LEPJL/FW, MEDJL/FW, MEPJL/FW, ATDJL/FW and ATPJL/FW were 0.165, 0.295, 0.232, 0.297, 0.281, 0.327, 0.3PJL, 0.558 and 0.313, respectively. No significant difference had been found between the left and right leg. A gender difference was only found statistically on the ratio of IPP, and also, no linear correlation was observed only between IPP and FW. Most of the difference values lain in a 4-mm threshold for MEDJL (95.81%), LEDJL (94.88%), MEPJL (97.21%), LEPJL (94.88%), ATPJL (93.49%) and ATDJL (100%). Significant differences were observed amongst different races. Conclusions AT, ME and LE can be used as reliable landmarks to locate the normal JL in Chinese population intraoperatively. It is meaningful to come up with a set of ratios to different races. [ABSTRACT FROM AUTHOR]