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Background: Human adipose stromal cells-derived extracellular vesicles (haMSC-EVs) have been shown to alleviate inflammation in acute lung injury (ALI) animal models. However, there are few systemic studies on clinical-grade haMSC-EVs. Our study aimed to investigate the manufacturing, quality control (QC) and preclinical safety of clinical-grade haMSC-EVs. Methods: haMSC-EVs were isolated from the conditioned medium of human adipose MSCs incubated in 2D containers. Purification was performed by PEG precipitation and differential centrifugation. Characterizations were conducted by nanoparticle tracking analysis, transmission electron microscopy (TEM), Western blotting, nanoflow cytometry analysis, and the TNF-α inhibition ratio of macrophage [after stimulated by lipopolysaccharide (LPS)]. RNA-seq and proteomic analysis with liquid chromatography tandem mass spectrometry (LC–MS/MS) were used to inspect the lot-to-lot consistency of the EV products. Repeated toxicity was evaluated in rats after administration using trace liquid endotracheal nebulizers for 28 days, and respiratory toxicity was evaluated 24 h after the first administration. In vivo therapeutic effects were assessed in an LPS-induced ALI/ acute respiratory distress syndrome (ARDS) rat model. Results: The quality criteria have been standardized. In a stability study, haMSC-EVs were found to remain stable after 6 months of storage at − 80°C, 3 months at − 20 °C, and 6 h at room temperature. The microRNA profile and proteome of haMSC-EVs demonstrated suitable lot-to-lot consistency, further suggesting the stability of the production processes. Intratracheally administered 1.5 × 108 particles/rat/day for four weeks elicited no significant toxicity in rats. In LPS-induced ALI/ARDS model rats, intratracheally administered haMSC-EVs alleviated lung injury, possibly by reducing the serum level of inflammatory factors. Conclusion: haMSC-EVs, as an off-shelf drug, have suitable stability and lot-to-lot consistency. Intratracheally administered haMSC-EVs demonstrated excellent safety at the tested dosages in systematic preclinical toxicity studies. Intratracheally administered haMSC-EVs improved the lung function and exerted anti-inflammatory effects on LPS-induced ALI/ARDS model rats. [ABSTRACT FROM AUTHOR]

Low or even zero carbon dioxide emissions will be an essential requirement for energy supplies in the near future. Besides transport and electricity generation, industry is another large carbon emitter. Hydrogen produced by renewable energy provides a flexible way of utilizing that energy. Hydrogen, as an energy carrier, could be stored in a large capacity compared to electricity. In Sweden, hydrogen will be used to replace coal for steel production. This paper discusses how the need for electricity to produce hydrogen will affect the electricity supply and power flow in the Swedish power grid, and whether it will result in increased emissions in other regions. Data of the Swedish system will be used to study the feasibility of implementing the hydrogen system from the power system viewpoint, and discuss the electricity price and emission issues caused by the hydrogen production in different scenarios. This paper concludes that the Swedish power grid is feasible for accommodating the additional electricity capacity requirement of producing green hydrogen for the steel industry. The obtained results could be references for decision makers, investors, and power system operators. [ABSTRACT FROM AUTHOR]

Phosphogypsum (PG) is a by-product of the wet phosphoric acid process, and anhydrous phosphogypsum (APG) prepared by PG calcination and ball milling pretreatment can be useful to prepare polypropylene composites by melt blending to yield polymer materials with improved properties. In this work, the hydrophobic effect of stearic acid (SA) modified APG was investigated by various analytical techniques. To this end, the modified APG was used as a filler for isotactic polypropylene (PP) blending to yield PP/APG composites and study the influence of APG particle size and added amount on the mechanical properties of PP/APG composites. The results showed SA coated on APG surface by chemical adsorption to form a hydrophobic layer. The water contact angle increased from 8.49° to 112.49° before to after modification, respectively. The mechanical properties of PP/APG composites were affected by the particle size and content of APG. Smaller particle size of APG led to better mechanical properties of PP/APG composites. At particle size d 50 of APG filler of 2.83 μm and content of 5 wt%, characteristics like the tensile strength, flexural strength, impact strength, and tensile modulus of PP/APG composites reached 37.28 MPa, 47.71 MPa, 6.18 KJ/m2, and 422.3 MPa, respectively. Compared to pure PP, these values increased by 4.66%, 5.4%, 27.68%, and 18.28%, respectively. Smaller particle size of APG was also found more conducive to the increase in APG content within PP/APG composites, as well as reduced production cost of composites. APG prepared from PG after treatment is useful as a filler for PP and other polymer materials, promising for PG resource utilization. [ABSTRACT FROM AUTHOR]

A series of polyacrylic salts are used as nucleating agents in isotactic polypropylene (iPP). Investigations are done on the mechanical characteristics, crystallization behavior, and melting behavior of nucleated iPP. According to the result from differential scanning calorimetry (DSC), the temperature at which nucleated iPP crystallize was 3–5 °C higher than the temperature at which pure iPP. Meanwhile, zinc polyacrylate, potassium polyacrylate, and sodium polyacrylate have the ability to induce β-crystals in iPP, according to wide-angle X-ray diffraction data. The optical microscope observation combined with DSC results shows that potassium polyacrylate had a β-nucleation effect when it had a lamellar crystal structure. When compared to pure iPP, the impact strength of iPP nucleated with sodium polyacrylate or potassium polyacrylate is improved by 23.48% and 24.35%, respectively. According to the mechanical properties results, there is no significant change in the tensile strength and flexural modulus of nucleated iPP with sodium polyacrylate and potassium polyacrylate. Without compromising its stiffness, sodium polyacrylate or potassium polyacrylate can increase the toughness of nucleated iPP. [ABSTRACT FROM AUTHOR]

A square matrix is said to have property n if there exists a positive integer w such that A w is nonnegative. In this paper, we study the core-EP monotonicity for property-n matrices. Some necessary and sufficient conditions for a property-n matrix to be core-EP monotone are given. Moreover, a necessary and sufficient condition for a real square matrix to have a nonnegative core-EP inverse is also presented. [ABSTRACT FROM AUTHOR]

The accuracy of models to capture the uncertainty of renewables significantly affects the planning and operation of renewable energy-based stand-alone (REB-SA) microgrids. This paper aims to first study different stochastic and deterministic models for renewables, then evaluate the performance of an REB-SA microgrid planning problem and provide qualitative and quantitative comparisons. A modified Metropolis-coupled Markov chain Monte Carlo simulation is considered for the first time in the planning of an REB-SA microgrid to predict the behavior of renewables with minimum iterations. The modified model is benchmarked against two prevalent models including the retrospective model with worst-case scenarios and the Monte Carlo simulation. The operations of three designed microgrids (by these three methods) are evaluated using the last three-year historical data of a city in northern Sweden including solar radiation, wind speed, the water flow of a river, and load consumption. The impacts of the considered methods on using PV panels and hydrogen systems are investigated. The results verify that the modified model decreases the risk of planning and operation of an REB-SA microgrid from the energy and power shortage viewpoints. Moreover, the designed microgrid with the modified model can cope with all possible scenarios from economic, technical, and environmental viewpoints. • Uncertainties of renewable energy are major concerns for replacing fossil-fuel energy. • A modified Metropolis-coupled MCMCS is applied to the microgrid planning problem. • Uncertainty modeling methods on microgrid planning and operation are benchmarked. • Microgrid planning is highly affected by different uncertainty modeling methods. • The planning results besides the benchmarks show economic and reliability improvement. [ABSTRACT FROM AUTHOR]

The sheet forming using flexible-die has been presented the great development potential, which uses the liquid, polyurethane rubber, rubber bladder, viscous medium, or magnetorheological fluid as the force transmission medium and shows some advantages. In this paper, the new method on the sheet flexible-die forming using the magnetorheological elastomer (MRE) is proposed. The MRE consists of magnetically polarizable particles locked into an elastomer matrix and has the magnetorheological effect under the action of a magnetic field. The mechanical property like the shear modulus of MRE can up to 160% in microseconds when the magnetic field is applied. Therefore, the performance behavior of MRE is controllable and adjusted, which can adapt the force requirements at different positions during the sheet metal forming process. Finite element analysis of Al1060 sheet bulge using MRE with different shear modulus was carried out. Results show that the right side of the FLD is obtained by using elliptical dies with different length–width ratios. On the basis of that a new method is proposed to obtain forming limit diagrams of sheet metal using the magnetorheological elastomer forming process at variable magnetic fields, bulging tests of the Al1060 sheet under different magnetic fields were implemented. FLD at different elliptical dies under the action of MRE is determined. An increase in forming limits of Al1060 with the increase in the magnetic field is observed. [ABSTRACT FROM AUTHOR]

Background: Renal epithelium lesions can cause renal cell carcinoma. This kind of tumor is common among all renal cancers with poor prognosis, of which more than 70% belong to kidney renal clear cell carcinoma. As the pathogenesis of KIRC has not been elucidated, it is necessary to be further explored.Methods: The Genomic Spatial Event database was used to obtain the analysis dataset (GSE126964) based on the GEO database, and The Cancer Genome Atlas was applied for KIRC data collection. edgeR and limma analyses were subsequently conducted to identify differentially expressed genes. Based on the systems biology approach of WGCNA, potential biomarkers and therapeutic targets of this disease were screened after the establishment of a gene coexpression network. GO and KEGG enrichment used cluster Profiler, enrichplot, and ggplot2 in the R software package. Protein-protein interaction network diagrams were plotted for hub gene collection via the STRING platform and Cytoscape software. Hub genes associated with overall survival time of KIRC patients were ultimately identified using the Kaplan-Meier plotter.Results: There were 1863 DEGs identified in total and ten coexpressed gene modules discovered using a WGCNA method. GO and KEGG analysis findings revealed that the most enrichment pathways included Notch binding, cell migration, cell cycle, cell senescence, apoptosis, focal adhesions, and autophagosomes. Twenty-seven hub genes were identified, among which FLT1, HNRNPU, ATP6V0D2, ATP6V1A, and ATP6V1H were positively correlated with OS rates of KIRC patients (p < 0.05).Conclusions: In conclusion, bioinformatic techniques can be useful tools for predicting the progression of KIRC. DEGs are present in both KIRC and normal kidney tissues, which can be considered the KIRC biomarkers. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a cluster of clinical syndromes with diverse etiologies that ultimately result in a swift decline in kidney function. Regrettably, AKI lacks effective therapeutic agents at present. Neferine, a bioactive alkaloid derived from Lotus Plumule, has been reported to alleviate AKI triggered by cisplatin, ischemia/reperfusion (I/R), and sepsis by inhibiting inflammatory pathways. However, the precise molecular mechanisms underpinning its renoprotective effects remain elusive. Peroxisome proliferator-activated receptor alpha (PPAR-α), a regulator of lipid metabolism with anti-inflammatory properties, was investigated in this study to examine its role in neferine’s renoprotective effects in cellular and mouse models of AKI. We found that neferine pretreatment in both I/R- or lipopolysaccharide (LPS)-induced AKI models inhibited the activation of the NF-κB inflammatory pathway and reversed PPAR-α deficiency. In NRK-52E cells exposed to hypoxia/reoxygenation (H/R) or LPS, overexpression of PPAR-α resulted in inhibition of the NF-κB pathway and TNF-α production, while PPAR-α silencing via siRNA transfection negated neferine’s anti-inflammatory effects. Furthermore, pretreatment with neferine not only reduced lipid accumulation but also reversed the downregulation of FAO-related enzymes induced by LPS. Our findings suggest that neferine’s renoprotective effects against AKI are partially mediated through the reversal of renal PPAR-α deficiency and subsequent inhibition of the inflammatory NF-κB pathway. Therefore, regulating renal PPAR-α expression by neferine could represent a promising therapeutic strategy for AKI. [ABSTRACT FROM AUTHOR]

Background: Circular RNAs (circRNAs) are pivotal regulators of various human cancers and circ-ERBB2 is abnormally expressed in breast cancer cells. However, the role and mechanism of circ-ERBB2 in HER2-positive breast cancer are still unknown.Methods: The circ-ERBB2 expressions in the tumor tissues of HER2-positive breast cancer patients were tested using quantitative real-time PCR. The circ-ERBB2 function was investigated by cell counting kit 8 assay, Transwell, flow cytometry and Western blot. Mechanistically, fluorescence in situ hybridization, RNA immunoprecipitation, RNA pull-down and dual-luciferase reporter gene assays were conducted to confirm the interaction between circ-ERBB2 and miR-136-5p or miR-198 in HER2-positive breast cancer cells.Results: Circ-ERBB2 was elevated in the tumor tissues of HER2-positive breast cancer patients. Functionally, the interference with circ-ERBB2 repressed HER2-positive breast cancer cell proliferation, migration, invasion and accelerated cell apoptosis. Furthermore, the mechanistic analysis corroborated that circ-ERBB2 acted as a competing endogenous RNA for miR-136-5p or miR-198 to relieve the repressive influence of miR-136-5p or miR-198 on its target transcription factor activator protein 2C (TFAP2C). Meanwhile, in vivo assays further corroborated the oncogenic function of circ-ERBB2 in HER2-positive breast cancer.Conclusions: Circ-ERBB2 accelerated HER2-positive breast cancer progression through the circ-ERBB2/miR-136-5p/TFAP2C axis or the circ-ERBB2/miR-198/TFAP2C axis. [ABSTRACT FROM AUTHOR]

Sheet flexible-die forming using a magnetorheological (MR) fluid, which can change the mechanical property of flexible-die during the forming process, has become an innovative technology with great application potential in manufacturing thin-walled complex components. Although it has been proved that using an MR fluid as a flexible-die can improve the sheet formability, there is still a lack of in-depth understanding and systematic research. In this paper, the bulging process using elliptical dies with six kinds of ellipticities was adopted to achieve different strain paths and obtain the tension-tension side of forming limit diagram (FLD). Experiments using three kinds of MR fluids and four magnetic field conditions were conducted to systematically study their effects on the tension–tension side of FLD. The effect of the magnetic field on the fracture pattern of the specimen and its mechanism were also discussed. Results showed that magnetic particle content and magnetic field condition have a comprehensive impact on the forming limit diagram. When an MR fluid with a magnetic particle content of 20% is used, the forming limit under different magnetic field conditions has little difference. When the magnetic particle content increases to 30%, the forming limit curve gradually increases with increasing magnetic flux density. But when it reaches 43%, the forming limit curve increased first and then decreased with the increase of magnetic flux density. Besides, the extended FLD of the Al1060-O sheet was established, in which the conventional forming limit diagram is expanded to consider the influence of the magnetic field condition. These results can provide guidance in the parameter selection of magnetic flux density and magnetic particle content in sheet flexible-die forming using an MR fluid. [ABSTRACT FROM AUTHOR]

Background: Nonalcoholic fatty liver disease (NAFLD) is strongly associated with type 2 diabetes mellitus (T2DM). Lifestyle intervention remains a preferred treatment modality for NAFLD. The glucagon-like peptide (GLP-1) receptor agonists and sodium-glucose cotransporter-2 (SGLT-2) inhibitors have been developed as new glucose-lowering drugs, which can improve fatty liver via an insulin-independent glucose-lowering effect. However, studies exploring the efficacy of GLP-1 receptor agonists combined with SGLT-2 inhibitors in patients with NAFLD and T2DM are scanty. Thus, the present randomised controlled trial aims at comparing the efficacy and safety of semaglutide plus empagliflozin with each treatment alone in patients with NAFLD and T2DM. Methods: This 52-week double-blinded, randomised, parallel-group, active-controlled trial evaluates the effects of semaglutide, empagliflozin and semaglutide + empagliflozin in 105 eligible overweight/obese subjects with NAFLD and T2DM. The primary outcome will be a change from baseline to week 52 in the controlled attenuation parameter, free fatty acid and glucagon. Secondary endpoints include changes in liver stiffness measurement, liver enzymes, blood glucose, lipid levels, renal function, electrolyte balances, minerals and bone metabolism, cytokines, high-sensitivity C-reactive protein, ferritin, anthropometric indicators, nonalcoholic fatty liver fibrosis score, fibrosis 4 score and homeostatic model assessment for insulin resistance. In addition, intention-to-treat, interim analysis and safety analysis will be performed. Discussion: This double-blinded, randomised, clinical trial involves a multi-disciplinary approach and aims to explore the synergistic effects of the combination of semaglutide and empagliflozin. The results can provide important insights into mechanisms of GLP-1 receptor agonists and/or SGLT-2 inhibitors in patients with NAFLD and T2DM. Trial registration: This study has been registered with Chinese Clinical Trial Registry (ChiCTR2300070674). [ABSTRACT FROM AUTHOR]

Swedish government's target is to have 100% renewable electricity production by 2040. Currently, hydropower contributes the majority of renewable electricity generation of the country. The wind power capacity has increased significantly in the past decade. In this paper, practical data is used to study the possibility of reaching the 100% renewable electricity generation goal by replacing existing thermal generations with wind power generations. It is found that the Swedish electricity generation system can reach 100% renewable by tripling the existing wind power capacity combined with the existing hydropower in the country. Based on current growth rate of wind power installation, the goal could be reached within 20 years. Hourly simulation shows that 100% renewable energy generation system composed by wind power and hydropower satisfy hourly operation requirements. • Sweden can reach 100% renewable generation by tripling existing wind capacity. • Sweden can reach 100% renewable generation goal within 20 years. • Coordinating hydropower and wind power satisfies hourly operation requirement. [ABSTRACT FROM AUTHOR]

Due to the visibility and controllability features of the latest distribution networks, there are potentials to model customer loads through a component-based approach more accurately. The electricity markets started in recent years enable trading and exchanges of electricity among traditional power stations and prosumers. It provides a possibility to improve the optimality of classical volt-var optimization (VVO) schemes. In this paper, a tri-level bottom-up load model and a market-based volt-var optimization (mVVO) model are proposed. The energy-to-voltage (ETV) parameter is proposed in our load model as a substitute for the widely used load-to-voltage (LTV) parameter to reflect long-term load characteristics. The mVVO model using ETV parameters aims to combine the optimal voltage regulation strategies and electricity purchase strategies from wholesale and retail markets for maximum cost saving. The case studies based on real load data of Hong Kong show that by coordinating the voltage regulation methods with market behaviors, utilities can reach a higher level of cost saving, in addition to energy saving. [ABSTRACT FROM AUTHOR]

The double-curved is the main feature of the sheet metal part, which is mainly used in automobile panels, aircraft skins, high-speed rail car bodies, etc. The forming process can easily lead to the local thinning and springback and seriously affect its forming quality. In this paper, the influence of the shear modulus of the flexible die on the thinning and springback of 6K21-T4 aluminum alloy for double-curved parts was analyzed by the numerical simulation method. Different rubber flexible die were selected for the forming process of the different double-curved parts, and the effect of the shear modulus on the thinning and springback of double-curved parts was obtained. Results show that the thickness reduction of the part formed by the rubber flexible die is reduced by 10.6% compared with that of the rigid punch forming. The maximum effective stress difference can be reduced by 67.4% and the springback can be reduced by 64.8% through optimizing the shear modulus of rubber flexible die. [ABSTRACT FROM AUTHOR]

To provide intelligent control options during sheet metal forming process, magnetorheological (MR) fluid has been applied as a property-adjustable flexible-die. However, the mechanism of the magnetic field effect on the sheet deformation behavior is not clear yet. In this paper, to clarify the deformation mechanism, the bulging behavior of thin-walled Al1060-O sheet was systematically investigated through experiment and numerical simulation. Special attention was paid to the effect of magnetic field on loading curve, bulge dome height, and thickness strain distribution. Results showed that the maximum bulging force increased obviously with the increase of magnetic flux density. The bulge dome height and thickness strain were influenced by magnetic field condition and magnetic particle content synthetically. Appropriate magnetic field condition and magnetic particle content can improve formability. However, excessive magnetic flux intensity and magnetic particle volume fraction, for example, B = 0.20 T and φ = 46%, would lead to premature rupture. Finite element analysis was adopted to assist in explaining the bulging behavior. Detailed analysis indicated that the flow stress variations caused by magnetic field affect the stress states, velocity distribution of MR fluid, and sheet/MR fluid contact condition, further leading to different stress and strain distribution of sheet metal. Finally it causes the great difference in specimen geometry and wall thickness distribution. [ABSTRACT FROM AUTHOR]

With the rapid development of network and multimedia technologies, the widespread use of images in social networks, military applications, and other fields has led to substantial demands for image encryption. To protect images from potential threats, most protocols perform multiple rounds of confusion and diffusion until a satisfactory security level is attained. However, this strategy is time-consuming and unable to meet the requirements for real-time video encryption. Consequently, many works realize video encryption by simplifying the encryption process, e.g. employing a single round of confusion and diffusion to encrypt each frame. To enhance security to the level of image encryption while ensuring real-time performance, this paper proposes a real-time video encryption protocol based on multi-round confusion-diffusion architecture. It splits the frame into subframes, uses a set of threads to concurrently perform confusion and diffusion. The statistical and security analyses demonstrate the proposed protocol exhibits exceptional statistical properties and is resistant to various attacks. The encryption speed evaluation shows that our method significantly enhances computational efficiency, achieving latency-free encryption of 512×512 24FPS videos using the Intel Xeon Gold 6226R@2.9GHz CPU. Even with the execution of four rounds of confusion and six rounds of diffusion operations on each frame, the average encryption time remains below 30ms. [ABSTRACT FROM AUTHOR]

• The dissociation of methane+ethane double hydrate samples was examined using in situ Raman spectroscopy. • Hydrate structures were found to transfer from sI to sII over a methane composition of 50 mol–68 mol%. • The occurrence time of structure transition is reduced with the increasing methane concentration. • The mechanism of the structural transition occurring in gas hydrate decomposition was proposed. The structural transition of methane-ethane gas hydrates is generally observed during the forming process; however, it has seldom been reported during the dissociation process. Study on the dissociation behavior of methane-ethane hydrate below ice point has important implications on gas storage and transportation. It was also be helpful for the natural gas hydrate production by depressurization in permafrost zones. The dissociation of a series of methane-ethane hydrate samples at atmospheric pressure and temperatures below ice point (272.15–269.15 K) was performed, and the influence of gas composition and temperature on the structural transition was examined using in situ Raman spectroscopy. The hydrate structures were found to transition from structure I to structure II over a methane composition range of 50–68 mol%. The hydrates remained as sI or sII type compounds, and no structural transition occurred during the dissociation when the methane content in methane-ethane gas mixture was decreased to a certain amount (<50 mol%) or increased to a higher value (≥70 mol%). Further investigation showed that the occurrence time of structural transition reduced with an increase in the methane concentration under the same decomposition temperature. Furthermore, hydrate dissociation was retarded upon decreasing the temperature in this temperature range (272.15–269.15 K). The mechanism of the structural transition occurring in gas hydrate decomposition was proposed. [ABSTRACT FROM AUTHOR]

The distribution of temperature in sand soils was measured through laboratory tests, and the temperature influence on friction resistances at the concrete-soil interface was analyzed. Based on the results of laboratory tests, the finite element model was established using the sequential thermal coupling method. The influences of temperature on the bearing characteristics of energy pile were analyzed. The analysis results show that the cyclic temperature will cause additional displacement along pile depth. It is pointed out that if applied vertical loads at energy pile head exceed the value from which nonlinear settlements would be initiated, irrecoverable additional settlement will occur at pile head. Based on the analysis results, a simplified approach was proposed to estimate the zero point of additional displacement along pile shaft and the additional axial pile force. The comparison between the calculated results obtained by the proposed method and that of ABAQUS on single energy pile was given to verify the accuracy of the proposed method. It is shown that reasonable predictions can be obtained without expensive and time-consuming analyses by the proposed method in this paper. [ABSTRACT FROM AUTHOR]

Ebselen is an organoselenium compound that has demonstrated potent antioxidant and anti-inflammatory effects in previous studies. The present study was conducted to evaluate the effect of ebselen on myocardial ischemia-reperfusion (I/R) injury in a rat model and to elucidate the related mechanisms. Myocardial infarct size was assessed using triphenyltetrazolium chloride staining. Myocardial injury was evaluated according to the histopathological and ultrastructural alterations of rat hearts and the serum activity levels of cardiac enzymes, including creatine kinase (CK), CK-MB isoenzyme and lactate dehydrogenase (LDH). Cardiomyocyte apoptosis was detected using the terminal dUTP nick end-labelling (TUNEL) assay. In addition, the expression of apoptosis-associated proteins was measured using western blot analysis. In heart tissue specimens the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and levels of malondialdehyde (MDA) and protein carbonyl (PC) were also detected. The results indicated that ebselen reduced I/R-induced increase in myocardial infarct size and prevented the I/R-induced decreases in ejection fraction and fractional shortening. Further of note, ebselen improved I/R-induced rat heart injury. This was indicated by attenuation of histological and ultrastructural changes; reduction of serum CK, CK-MB and LDH activity levels; and decreased cell apoptosis on TUNEL staining, which was verified by decreased expression of cleaved (C)-Caspase-8, C-Caspase-3, B-cell lymphoma 2 (Bcl-2)-associated X protein and C-PARP, and increased expression of Bcl-2. Additionally, SOD and GPx activity levels were significantly higher, while MDA and PC levels were significantly lower in the ebselen + I/R group compared with in the I/R group. In conclusion, the present results suggested that ebselen serves an important role in protecting against myocardial I/R injury. The underlying mechanism may involve suppression of cardiomyocyte apoptosis and promotion of antioxidant activity. [ABSTRACT FROM AUTHOR]

Abstract: In this study, first‐principles calculations were performed to study the stability, mechanical property, electronic structure and lattice dynamics of β‐Si3(Cx,N1−x)4 silicon carbonitride. The solubility of carbon in β‐Si3(Cx,N1−x)4 having a stable structure is shown to be about 15 at.%. Within the limit of solubility, an increase in carbon concentration in β‐Si3(Cx,N1−x)4 will lead to a decrease in the Young's modulus and density and an increase in the Poisson's ratio. The study of deformation behavior shows that the most likely slip system of 1 1 ¯ 00 0001 is on prismatic plane rather than on basal plane. This feature of β‐Si3(Cx,N1−x)4 is similar to WC. In addition, the ductility and fracture toughness of β‐Si3(Cx,N1−x)4 can be optimized by controlling the carbon concentration. The improvement in ductility and fracture toughness can be attributed to the formation of metallic bonds by the incorporation of carbon atoms. The lattice dynamics study shows that the structural stability of β‐Si3(Cx,N1−x)4 is controlled by energy stability criteria under stress‐free condition. In the stressed state, the structural stability of β‐Si3(Cx,N1−x)4 is controlled by the elastic stability criteria. Subsequently, the β‐Si3(Cx,N1−x)4 solid solution was prepared by self‐propagating high‐temperature synthesis (SHS), and the carbon‐concentration‐dependent mechanical properties were consistent with the first‐principles calculations. The maximum fracture toughness of 10.4 MPa·m0.5 was obtained in β‐Si3(Cx,N1−x)4 at carbon concentration of 5 wt%, which means that the solid solution toughening can be used as a supplement to crack bridging toughening and phase transition toughening for ceramic toughening. The results obtained in this study reveal that the β‐Si3(Cx,N1−x)4 solid solution is a promising candidate for high‐speed ceramic bearings. [ABSTRACT FROM AUTHOR]

In flexible die forming processes employing semi-solid or elastic materials as pressure-carrying medium, there exist tangential adhesive stress or friction at medium/blank interface, which may improve sheet formability and has been experimentally verified. However, the mechanism behind this phenomenon has not been clarified yet. In order to fill this gap, analytical investigations were implemented in this paper based on previous studies involving through-thickness shear stress. Concretely, the analytical model of axisymmetric shell bulging process considering tangential adhesive stress and the extended M-K model under non-planar stress state were established at first. Accordingly, the relationship between tangential adhesive stress and through-thickness shear strain was deduced together with the relationship between through-thickness shear stress (strain) and sheet forming limit. On the basis of that, the viscous pressure forming (VPF) process was taken as an example to exhibit the characteristic that forming limit changes with tangential viscous adhesive stress and through-thickness shear stress (strain). It is shown that the tangential viscous adhesive stress has positive correlation with through-thickness shear strain which results in increased sheet formability. Tube bulging tests employing viscous medium with different molecular weight as pressure-carrying medium were conducted to give an experimental evidence of the proposed analytical results. [ABSTRACT FROM AUTHOR]

CO 2 replacement is considered as a promising method for the simultaneous development of natural gas hydrate and CO 2 sequestration. The addition of small molecular gases, such as N 2 and H 2 , into the injected gas can increase the gas recovery ratio and prevent CO 2 liquefaction. Based on previous studies, this work presents methane hydrate exploitation using the CO 2 /H 2 continuous injection-production mode. The mechanism combines gas sweep with CH 4 /CO 2 replacement. A series of experiments were carried out to optimize the injected gas composition and flow rate, which have a significant effect on the rate of CH 4 hydrate decomposition, amount of CO 2 sequestration, and cost. The compositions of the injected gases had little effect on the recovery rate when a relatively higher flow rate was employed. A balance between CH 4 production and CO 2 sequestration was established when the CO 2 mole fraction was slightly <74%, and the temperature of the reservoir did not decline throughout the whole process. The injection rate affected both the displacement efficiency and the production cost. Moreover, through these experiments, we discovered a more economically feasible and productive measure for regulating the injection rate. [ABSTRACT FROM AUTHOR]

For a rigid-plastic solid obeying Tresca's yield criterion which deforms by the mechanism of extended slip, it conforms to the principle of rotation-rate continuity if the yield shear stress remains constant. It has been proved on this basis that the divergence of the strain-rate tensor is zero and the velocity vector field obeys the Laplace equation in the deformation region. This property can lead to two general solutions, one is derived into three-dimensional slip-line field theory; the other is applied to solve the problem of transverse deflection of a clamped plate deflected by a flat-ended rigid punch. For concentric loading conditions explicit analytical solutions can be obtained directly, while for eccentric loading conditions the method of fundamental solutions (MFS) is applied in the deformation region which is seen as a doubly-connected domain obeying the harmonic equation. The punching force needed for the deflection and strain components are then calculated. It has been obtained that the contour lines and the lines of steepest descent are two principle lines of any point in the deformation region, so the method of steepest descent is used to depict the trajectories of the principle lines. Numerical calculations have been made using commercial finite element software ANSYS-LSDYNA. It turns out that the results obtained from numerical calculations fit quite well with the analytical results based on the principle of rotation-rate continuity and MFS. Finally, NURBS curves and Coons surface are used to construct the configurations of slip-planes in this problem, where the normal of slip-planes and the planes on which the two families of slip-lines located are both curved. [ABSTRACT FROM AUTHOR]

Chaotic cryptography has been extensively investigated over the past three decades, especially in the field of digital chaotic cryptography. In this paper, we propose a new digital chaotic stream cipher based on double piecewise linear chaotic maps. It initially takes four real numbers as the key, periodically updates the chaotic maps, and efficiently outputs the bit strings. Theoretical analysis shows that our protocol achieves higher anti-cryptanalysis capacities, effectively alleviates the dynamical degradation problem, and thus reaches higher security. Statistical evaluation demonstrates that our protocol can generate bit strings with outstanding statistical properties. In addition, we apply our protocol to image encryption and decryption. Experimental results verify the conclusions of the statistical evaluation, and prove the strong sensitivity of the protocol to the key. [ABSTRACT FROM AUTHOR]

The accumulated antibiotics in the aquatic environment pose great threat to human and ecological health, boosting the development of porous materials for antibiotic removal. Mesoporous metal-organic frameworks (MOFs) have shown great promise in adsorption, which, however, usually need supramolecular design or cooperative template strategy for synthesis. Here we report the successful construction of mesoporous zirconium based metal-organic frameworks (Zr-MOFs) via a simple solvent-dependent strategy. Regulation of the ratio of water to N, N-dimethylacetamide during synthesis determined the porous structure of the synthesized MOFs. Systematic characterizations including SEM, FTIR, XRD and nitrogen sorption isotherm were carried out for structure analysis of the MOFs. With water fraction of 20% (v/v), the obtained Zr-MOF exhibited the highest adsorption capacity (Q max of 337.0 mg⋅g−1) towards tetracycline (TC). The adsorption kinetics fitted the pseudo-second-order kinetics, and the adsorption isotherms fitted the Freundlich model well. Adsorption mechanism investigation revealed that the abundant Zr–OH groups stemming from coordination defects mainly accounted for TC adsorption. The hydrogen bonding interaction between TC and Zr-MOF and the generated mesopores contributed to the satisfactory adsorption capacity. This work is anticipated to provide insights on facile synthesis of mesoporous MOFs and application in environmental remediation. • The solvent-dependent strategy was used to construct defective Zr-MOF adsorbent. • Zr-MOF-20 with mesoporous possess high adsorption capacity of 337.0 mg g−1 for TC. • Adsorption experiments proved the mechanisms involve hydrogen bond and pore filling interactions. [ABSTRACT FROM AUTHOR]

• Joint planning of capacitor, dispatchable DG, and energy storage with renewables. • Improve technical and economic effects of Volt-VAR optimization for energy saving. • High accuracy and low computational burden through MultiGMM-based data cluster. • Adaptive to scenario-based planning problems in large-scale distribution systems. • Provide incentives for distribution companies to invest in Volt-VAR optimization. With recent installations of intermittent renewable energy generations in electric distribution systems, their impacts on classical Volt-VAR optimization (VVO) schemes, especially the energy-saving effects, are becoming one of the major issues. The optimality of VVO schemes is hard to be guaranteed due to voltage fluctuations caused by distributed renewable generations. Distributed energy resources (DERs) could be a solution to provide flexibilities to improve VVO performance if the high cost is lowered while their locations and sizes are optimized. In this paper, an optimization model is proposed for a joint planning of capacitors, dispatchable distributed generators, and energy storage to improve VVO energy-saving effects while minimizing the system operating cost. The uncertainties of renewable energy resources, electricity demand, and electricity prices are accurately modeled benefited from emerging data analysis technologies. The technical and economic effects of the proposed model are proved and tested using real data sets and compared with classical models. The high precision of the proposed model is verified using time-series simulations. [ABSTRACT FROM AUTHOR]

In the twenty-seven years since the discovery of hepatitis C virus (HCV) the majority of individuals exposed to HCV establish a persistent infection, which is a leading cause of chronic liver disease, cirrhosis and hepatocellular carcinoma. In developed nations, the cure rates of HCV infection could be over 90% with direct-acting antiviral (DAA) regimens, which has made the great progress in global eradication. However, the cost of these treatments is so expensive that the patients in developing nations, where the disease burden is the most severe, could not afford it, which highly restricted its access. Additionally, the largely asymptomatic nature of infection facilitates continued transmission in risk groups due to limited surveillance. Consequently a protective vaccine and likely emergence of drug-resistant viral variants call for further studies of HCV biology. In the current review, the development and the progress of preventive and therapeutic vaccines against the HCV have been reviewed in the context of peptide vaccines, recombinant protein vaccines, HCV-like particle, DNA vaccines and viral vectors expressing HCV genes. [ABSTRACT FROM AUTHOR]

Abstract: Inactivated mycobacterium phlei (M. phlei) is well known for its immune‐stimulatory functions in humans and livestock, but less information is available about the influence on meat quality of pigs when used as a feed additive. This study was designed to evaluate the effects of inactivated M. phlei on growth performance as well as meat quality of fattening pigs. A total of 240 cross‐bred pigs ([Landrace × Yorkshire] × Duroc) with initial body weight of 80.14 ± 0.29 kg were randomly allocated to five treatments, each of which consisted of eight replicates with 6six pigs per replicate. The basal diet supplemented with five levels of inactivated M. phlei preparations (0, 3.5 × 109 [0.1% w/w], 7 × 109 [0.2%], 1.4 × 1010 [0.4%] or 2.1 × 1010 [0.6%] colony‐forming units/kg) was respectively fed to the control group and four treatment groups for 30 days. Adding 0.4% of inactivated M. phlei to diet increased the average daily feed intake and average daily gain of pigs. Importantly, intramuscular fat percentage in the Longissimus dorsi (LD) was increased by feeding diet containing 0.2%, 0.4% and 0.6% of inactivated M. phlei, despite the pH value, drip loss, cooking loss and filter paper fluid uptake not being influenced. Analysis of the fatty acid components showed that some saturated fatty acids were decreased in LD after feeding inactivated M. phlei, but some monounsaturated fat acids (MUFAs) and polyunsaturated fatty acids were increased (PUFAs), which induced the total contents of MUFAs and PUFAs were improved. RT‐PCR assay revealed that feeding inactivated M. phlei up‐regulated genes implicated in fat metabolism in muscle, including ELOVL6, FASN, SCD1 and H‐FABP. This study revealed that feeding inactivated M. phlei not only increased growth performance of fattening pigs, but also improved the meat quality by increasing intramuscular fat content, thus inactivated M. phlei probably has high utilization value in modern pig production. [ABSTRACT FROM AUTHOR]

As the penetration of uncontrollable renewable energy sources (RESs) increases, energy storage and flexible demand will play a more important role in future power systems. In this paper, air-conditioning systems with thermal energy storage (A/C storage systems) are studied as a way of compensating uncertainties from wind power. Wind power forecast errors are analyzed from different perspectives in order to better assist the schedule of storage devices. An operation scheme is proposed for A/C storage systems for both day-ahead scheduling and real-time operation, based on the features of wind power forecast errors. The targets include load management and compensation of wind power forecast errors. Simulations illustrate the effectiveness of the proposed scheme to support power systems with high wind penetration. [ABSTRACT FROM AUTHOR]

An effective pyridine based U-shaped template has been developed to enable a diverse range of meta-C-H functionalizations of phenylacetic acid scaffolds. This new template has extended the reaction scope to cross-coupling with ArBF3K as well as iodination using 1,3-diiodo-5,5-dimethylhydantoin as the iodination reagent. [ABSTRACT FROM AUTHOR]

Since sheet aluminum is of low room temperature formability, defects such as excessive thinning, wrinkling, and fracture may easily occur in pressure forming processes. The main purpose of this paper is to research the formability and performance of aluminum hoods in viscous pressure forming (VPF) under an appropriate control of blank holder force (BHF). A new strategy was proposed to determine the reasonable BHF loading condition. Constant and variable BHF were applied to a hood through a proposed design of multipoint BHF loading system. Hood forming experiments under three typical BHF loading schemes were conducted. Research results showed that when a higher initial constant BHF was followed by a gradual decrease in force, the maximum local thinning of the formed hood was 23.3%. When a lower initial constant BHF was followed by a gradual increase in force (the proposed scheme based on the new strategy), the thinning was 18.5%. The thickness strain, microhardness, and microstructure at typical positions of the formed hood under the proposed BHF loading scheme were also investigated. Research results demonstrated that the proposed strategy is an effective method to determine an appropriate BHF loading scheme to improve the panel's formability and obtain a high-quality thin-walled aluminum hood in VPF. [ABSTRACT FROM AUTHOR]

High-frequency ultrasound imaging has been widely adopted for assessment of the degenerative changes of articular cartilage in osteoarthritis (OA). Yet, there are few reports on investigating its capability to evaluate subchondral bone. Here, we employed high-frequency ultrasound imaging (25 MHz) to examine in vitro the tidemark in cylindrical osteochondral disks (n = 33) harvested from advanced OA knees of humans. We found good correspondence in morphology observed by ultrasound imaging and micro-computed tomography. Ultrasound roughness index (URI) of tidemark was derived from the raw radiofrequency signals to compare with bone quality factors, including bone volume fraction (BV/TV) and bone mineral density (BMD) measured by micro-computed tomography, using the Spearman correlation (ρ). URI of the tidemark was negatively associated with the subchondral plate BV/TV (ρ = -0.73, p <0.001), BMD (ρ = -0.40, p = 0.020), as well as the underneath trabecular bone BV/TV (ρ = -0.39, p = 0.025) and BMD (ρ = -0.43, p = 0.012). In conclusion, this preliminary study demonstrated that morphology measured by high-frequency ultrasound imaging could reflect the quality of the subchondral bone. High-frequency ultrasound is a promising imaging tool to evaluate the changes of the subchondral bone in addition to those of the overlying cartilage in OA. [ABSTRACT FROM AUTHOR]

The electrochemical fingerprints of Radix Paeoniae Alba were studied by chemical oscillation system of H+-Mn2+-CH3COCH3-BrO3-. Influences of variety of Radix Paeoniae Alba for the chemical oscillation system were studied. Finally, 43 °C temperature, 500 rpm stirring rate, 1000 mg Radix Paeoniae Alba, 2.0 mol·L-1 hydrogen ion concentration, 0.084 g MnSO4, 0.835 g KBrO3, 1mL acetone and 100 mL total volume were chosen as the optimal experimental conditions. The results indicated that the electrochemical fingerprints of Radix Paeoniae Alba from different regions showed significantly different characteristics, so the electrochemical fingerprint is a efficacious method to identify the regions and variety of Radix Paeoniae Alba. [ABSTRACT FROM AUTHOR]

Given a locally compact quantum group G, we define and study representations and C*-completions of the convolution algebra L1(G) associated with various linear subspaces of the multiplier algebra Cb(G). For discrete quantum groups G, we investigate the left regular representation, amenability and the Haagerup property in this framework. When G is unimodular and discrete, we study in detail the C*-completions of L1(G) associated with the non-commutative Lp-spaces Lp(G). As an application of this theory, we characterize (for each p ∊ [ 1;∊) the positive definite functions on unimodular orthogonal and unitary free quantum groups G that extend to states on the Lp-C*-algebra of G. Using this result, we construct uncountably many new examples of exotic quantum group norms for compact quantum groups. [ABSTRACT FROM AUTHOR]

The traditional two-dimensional Otsu algorithm only considers the limitations of the maximum variance of between-cluster variance of the target class and background class; this paper proposes evolutionary game improved algorithm. Algorithm takes full consideration of own pixel cohesion of target and background. It can meet the same of maximum variance of between-cluster variance. To ensure minimum threshold discriminant function within the variance, this kind of evolutionary game algorithm searching space for optimal solution is applied. Experimental results show that the method proposed in this paper makes the detail of segmentation image syllabify and has better antijamming capability; the improved genetic algorithm which used searching optimal solution has faster convergence speed and better global search capability. [ABSTRACT FROM AUTHOR]

Corrugated rings made of difficult-to-deform superalloy sheet with extremely thin wall are hardly manufactured since the forming processes are rather sensitive to parameters, such as axial feeding, cavity pressure, contact pressure, and so forth. The quasi-bulk forming method proposed in the author's previous work, which gets rid of axial compression, was demonstrated to be an effective solution. In this work, forming strategy based on the controlling of material flow in this process is further developed. Since the pressure-carrying medium (i.e., viscous medium) is of high viscosity, the sealing pressure of this process is lowered down in comparison with that of forming processes utilizing nonviscous fluid as forming medium. The contact pressure at blank ends becomes adjustable as a result. Effects of contact pressure at sealing/blank interface ( P ) on the blank draw-in were investigated numerically. An optimal load path of P was obtained. Regulatory mechanism of contact pressure was presented, and contact pressure was considered to be the resultant pressure caused by the static pressure ( P ) and cavity pressure ( P ). Thereafter, process optimization was conducted through adjusting the path of P to approximate to the optimal path of P . On the basis of that, geometrical parameters of die cavity were improved and forming experiments were conducted accordingly to form two sorts of nickel-based superalloy corrugated rings. Sufficient blank draw-in was observed and thickness thinning is acceptable. The forming strategy, which is based on the adjustment of contact pressure, was verified to be feasible to improve the manufacturability of thin-walled corrugated rings. [ABSTRACT FROM AUTHOR]

This study presents a market model that procures energy and performance‐based regulation services simultaneously considering the participation of energy storage devices. The correlations of energy, regulation capacity, and regulation mileage are explicitly demonstrated. The proposed market model determines the energy schedule of generation units, charging and discharging profiles of energy storage devices, and the schedule of regulation services. Market clearing prices for energy, regulation capacity, and regulation mileage are derived and decomposed through Lagrange multiplier analysis. The relationships between the clearing prices of different market products are analysed. The proposed market model is tested and verified with the IEEE 30‐bus system. [ABSTRACT FROM AUTHOR]

To study the large-deformation settlement of soft soil foundations, an analysis of the large-strain consolidation of soil in a Lagrangian coordinate system based on continuum mechanics is performed, and the control equations with the displacement gradient are obtained in this paper. Based on the nonlinear permeability and compressibility of soft soil foundations, the equation of large-strain nonlinear consolidation is established. Then, the finite difference method is used to solve the governing equations. Under the condition of two-sided drainage while considering the soil self-weight stress, it is found that the distribution of excess pore pressure is not symmetric along the depth of the foundation. The position of the maximum excess pore pressure appears below the midpoint of the soil foundation. The deviation degree increases with increasing foundation thickness and semilogarithmic compression index C c value, and it decreases with increasing semilogarithmic permeability index C k value. The calculations show that setting the drainage layer position close to the position of maximum excess pore pressure can effectively improve the drainage ability of the upper and bottom soil layers, which is beneficial to consolidation, and that the deviation distance is related to the C c and C k values. [ABSTRACT FROM AUTHOR]

Zr 4+ , Ge 4+ doped and co-doped TiO 2 nanoparticles were prepared by a ‘one-pot’ homogeneous precipitation method. The photocatalytic reaction kinetics of DMMP and the disinfection efficiency of HD, GD and VX on the samples were investigated. By means of a variety of characterization methods, especially the positron annihilation lifetime spectroscopy, the changes in structure and property of TiO 2 across doping were studied. The results show that the reasonable engineering design of novel photocatalysts in the field of CWAs decontamination can be realized by adjusting the bulk-to-surface defects ratio, except for crystal structure, specific surface area, pore size distribution and light utilization. [ABSTRACT FROM AUTHOR]

The importance of the performance of frequency regulation has already been acknowledged by regulators and Independent System Operators (ISOs). A performance-based frequency regulation market model considering both regulation capacity and regulation mileage constraints is proposed in this paper. In the proposed market, high-performance regulation resources have higher priorities to be selected in the market. Market clearing prices are derived with Lagrange relaxation. The analysis of the components of market clearing prices accurately indicates the correlation between regulation capacity and regulation mileage. To accommodate the proposed regulation market design, AGC allocation algorithm is adjusted based on the market clearing results. The clearing procedure of the market model is demonstrated on an illustrative case. The proposed market design is tested and verified with market simulations and system dynamic simulations. Simulation results are discussed and compared to show the effectiveness of the proposed market design. [ABSTRACT FROM AUTHOR]

Deformation states of sheet metals are determined by the in-plane stress distribution, which is closely related to forming load transmitted by forming medium. Mechanical properties of conventional forming medium, such as mineral oil, gas, and polyurethane, can hardly be controlled during the whole forming process. However, if the mechanical properties of forming medium can be freely altered, the stress state of sheet metal may become controllable. As a result, the magneto-rheological (MR) fluid was employed as a property-adjustable forming medium in this paper, which attempted to extend sheet formability in a controllable way. Effects of magnetic flux density ( B ) and iron particle content ( φ ) on yield stress of MR fluid in compression mode were analyzed at first. Magneto-rheological pressure bulging (MRPB) tests for Al1060-O sheet were conducted under different sets of parameters. Effects of B and φ on forming load were presented to show the adjustable mechanical properties of forming medium. Extended forming limit diagram (e-FLD) was proposed to describe the variation of sheet forming limit. The results indicate that sheet forming limit can be extended by monotonously increasing B in a certain range. The appropriate range of B is correlated to φ . The through-thickness shear stress caused by the transverse friction between MR fluid and sheet metal is considered to be responsible for this increase. The proposed process is demonstrated to be an efficient method to control the sheet formability, and more practical application may be expectable. [ABSTRACT FROM AUTHOR]

The morphology and structure of hydrate films of pure methane and methane+ethane mixtures were studied by suspending a single gas bubble in liquid water. The methane+ethane gas mixtures, containing 20 mol% or 81–89 mol% methane, were used to form hydrate films with different crystal structures. Polyhedral structures appeared on the background of uniform polycrystalline hydrate films formed by gas mixtures with a high methane mole fraction of 0.81–0.82. Some of the polyhedral structures are holes, and others are separated structure II polyhedral hydrate crystals. However, for pure methane, a gas mixture with a lower CH 4 mole fraction of 0.2, or a gas mixture with a higher CH 4 mole fraction of 0.89, the morphology is uniform through the whole hydrate film. The crystal structures in the hydrate film were determined using in situ Raman spectra. The results show that both pure methane and the gas mixture with a lower CH 4 mole fraction of 0.2 form a hydrate film with structure I. The single polyhedral crystal appeared in the background of the uniform polycrystalline hydrate film formed by gas mixtures with a high methane mole fraction of 0.81–0.82 as a structure II CH 4 -C 2 H 6 double hydrate crystal. The hole is mainly gas with an initial small amount of structure I hydrate, and that hole will be filled with structure II hydrate after a certain time. The experimental methods and the new findings presented in this work should be significant for the further research of hydrate growth kinetics. [ABSTRACT FROM AUTHOR]

Let B ( n , k ) be the set of all ( 0 , 1 ) -matrices of order n with constant line sum k and let ν ˜ ( n , k ) be the minimum rank over B ( n , k ) . It is known that ⌈ n / k ⌉ ≤ ν ˜ ( n , k ) ≤ ν ˆ ( n , k ) ≤ ⌊ n / k ⌋ + k , where ν ˆ ( n , k ) is the rank of a recursively defined matrix A ˆ ∈ B ( n , k ) . Brualdi, Manber and Ross showed that ν ˜ ( n , k ) = ⌈ n / k ⌉ if and only if k | n . In this paper, we show that ν ˜ ( n , k ) = ⌊ n / k ⌋ + k if and only if ( n , k ) satisfies one of the following three relations: (i) n ≡ ± 1 ( mod k ) , k = 2 or 3; (ii) n = k + 1 , k ≥ 2 ; (iii) n = 4 q + 3 , k = 4 and q ≥ 1 . Moreover, we obtain the exact values of ν ˜ ( n , 4 ) for all n ≥ 4 and determine all the possible ranks of regular ( 0 , 1 ) -matrices in B ( n , 4 ) . We also present some positive integer pairs ( n , k ) such that ν ˜ ( n , k ) < ν ˆ ( n , k ) < ⌊ n / k ⌋ + k , which gives a positive answer to a question posed by Pullman and Stanford. [ABSTRACT FROM AUTHOR]

Magnetorheological fluid (MR fluid), a kind of smart material, has been used as a new pressure-carrying medium in magnetorheological pressure forming (MRPF). The mechanical property of MR fluid under the pressure significantly affects the sheet formability. However, there is little knowledge on the deformation behavior of MR fluid under three-dimensional stress states. In this paper, a new procedure via a combination of extrusion test and FEM simulation has been proposed to determine the flow stress of MR fluids. The experimental device for extrusion test of MR fluids was designed. The flow stresses of a MR fluid (MRF-J01T) under four different magnetic fields were determined through the proposed procedure. In addition, the obtained flow stresses were used in the following FEM simulations to verify the accuracy by comparing with the experimental results. The simulation results were in good agreement with the experimental data, which supports the correctness and practicability of the proposed method. [ABSTRACT FROM AUTHOR]

Object detection plays a critical role for automatic video analysis in many vision applications. Background subtraction has been the mainstream in the field of moving objects detection. However, most of state-of-the-art techniques of background subtraction operate on each pixel independently ignoring the global features of images. A motion detection method based on subspace update of background is proposed in this study. This method uses a subspace spanned by the principal components of background sequence to characterise the background and integrates the regional continuity of objects to segment the foreground. To deal with changes in the background geometry, a learning factor is introduced into the authors' model to update the subspace timely. Additionally, to reduce computational complexity, they use two-dimension principal component analysis (PCA) rather than traditional PCA to obtain the principal components of background. Experiments demonstrate that the update policy is effective and in most cases this proposed method can achieve better results than others compared in this study. [ABSTRACT FROM AUTHOR]

Novel Zr 4+ and Ge 4+ co-doped titanium dioxide (Zr–Ge–TiO 2 ) nanoparticles for photocatalytic degradation of Chemical Warfare Agents (CWAs) were prepared via a homogeneous precipitation method. Considering the volatilization of solvents, solubility to CWAs, and compatibility with sensitive equipments, hydrofluoroether (HFE) was first used as the dispersion solvent of suspension decontaminants. Here, Zr (5.02 wt%)–Ge (0.94 wt%)–TiO 2 with the specific surface area of 447.9 m 2 g −1 exhibited the best photocatalytic performance. This was dispersed in HFE-458 (HCF 2 CF 2 CH 2 OCF 2 CF 2 H) and HFE-6512 (HCF 2 CF 2 CF 2 CF 2 CH 2 OCF 2 CF 2 H) respectively. A new gas collection system was designed to study volatilization in the reaction process. As a result, HFE-6512 is more suitable as the dispersion solvent than HFE-458. The suspension prepared with HFE-6512 not only has higher degradation efficiency of HD, GD, VX, 2-CEES and DMMP, but also has fewer volatile agents. Under simulated sunlight irradiation, both the surface removal and the degradation efficiency of HD, GD, VX, 2-CEES and DMMP were over 99.95% after 37 min. The results show that this suspension has potential applications in decontamination of CWAs on sensitive equipment materials. With high absorbing efficiency of CWAs and their simulants, the designed gas collection system is reliable for the selection of solvents and improvement of disinfection effect. [ABSTRACT FROM AUTHOR]

Excessive thinning of wall thickness caused by the unstable deformation of metals is the main failure mode in the manufacturing of thin-walled circular rings with complex section. A novel quasi-bulk forming method is proposed in this work to deal with this problem through achieving a stable state of metal flow. Metallic materials and viscous medium with different strain rate sensitive exponents ( m ) were respectively employed as core materials (i.e. pressure-carrying medium) in finite element analysis (FEA) to investigate the effects of core materials on the deformation behaviors of ring-shaped metal blank. Numerical results indicate that viscous medium and metal blank deform synchronously like a composite billet when appropriate viscous medium acts as core material. It is attributed to the adhesive attraction between viscous medium and metal blank caused by the high viscosity of viscous medium. In this condition, the composite billet easily fills the die cavity, which is similar to the way that round billets fill the die cavity in bulk forming processes. In order to verify the validity of quasi-bulk forming method, two types of thin-walled circular rings with corrugated meridians were formed through proposed method in the forming experiments. The maximum wall thickness reduction of formed parts is less than 8%. The present study demonstrates the quasi-bulk forming method can not only inhibit wall thickness thinning of thin-walled parts but simplify the process control. Thus, it may become a key process to fabricate thin-walled circular rings with large diameter variation per unit axial length ( ψ ). [ABSTRACT FROM AUTHOR]

Hepatitis C virus (HCV) infection tends persistent and causes chronic liver diseases, including inflammation, cirrhosis and hepatocellular carcinoma. Innate immune responses triggered by HCV infection, particularly the production of interferons and pro-inflammatory cytokines, shape the early host antiviral defense, and orchestrate subsequent HCV-specific adaptive immunity. Host has evolved multifaceted means to sense HCV infection to induce innate immune responses, whereas HCV has also developed elaborate strategies to evade immune attack. Recent studies in the field have provided many new insights into the interplay of HCV and innate immunity. In this review, we summarized these recent advances, focusing on pathogen recognition by innate sensors, newly discovered anti-HCV innate effectors and new viral strategies to evade innate immunity. [ABSTRACT FROM AUTHOR]