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Erosion caused by solid particles in a pipeline is one of the main problems endangering the safety production of the oil and gas industry, which may lead the equipment to malfunction or even fail. However, most of the previous studies focused on the standard elbow, and the erosion law of right-angle elbow and blind tee is rarely reported in the literature. This work aims to investigate the erosion law of different pipeline structures including 90° elbow, right-angle pipe, and tee pipe based on the production characteristics and engineering parameters of the gas field. An integrated CFD-DPM method is established including a realizable k-ε turbulence model, discrete phase model, and erosion rate prediction model. The accuracy of the model is evaluated by a series of experimental data of flow conditions of our previous work. Further, the erosion rate, pressure distributions, and particle trajectories in 90° elbow, right-angle pipe, and tee pipe under different flow velocities, particle mass flow rate, pipe diameter are investigated by applying the presented model. The results show that the blind tee has the most obvious growth rate, and the most serious erosion is located in the blind end of the pipe wall. The maximum erosion rate of the 1.5D is greater than that of the 3D elbow as a whole, and the 1.5D elbow is more concentrated in the serious erosion area. Furthermore, the erosion rate of the bend weld is much greater than that of the straight pipe weld. This study can provide a basis for the selection of different structural pipe fittings, thereby reducing the pipeline erosion rate and improving the integrity of the management of gas pipelines.

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Endothelial injury, characterized by an inflammatory response and increased permeability, is an initial stage of atherosclerosis (AS). Adenosine 5′-monophosphate (AMP), activated protein kinase (AMPK), and Nuclear Factor kappa B (NF-κB)/Yin Yang 1(YY1) signaling pathways play important roles in the process of endothelial injury. Berberine (BBR), a bioactive alkaloid isolated from several herbal substances, possesses multiple pharmacological effects, including anti-inflammatory, antimicrobial, antidiabetic, anticancer, and antioxidant activities. Previous studies showed a protective effect of berberine against endothelial injury. However, the underlying mechanism remains unclear. We explored the potential effect of BBR on TNF- (tumor necrosis factor-) α-induced injury of human umbilical endothelial cells (HUVECs) and studied its possible molecular mechanism. In the present study, HUVECs were divided into three groups. HUVEC viability was measured with Cell Counting Kit-8 assay. Extracellular lactic dehydrogenase (LDH) concentration was measured with LDH leakage assay. Endothelial microparticle (EMP) numbers were evaluated by flow cytometry analysis assay. The expression of proinflammatory cytokines was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA). The mRNA expression of NF-κB and YY1 was detected by Real-Time PCR (RT-PCR). The protein expression of NF-κB, YY1, and AMPK was detected by immunofluorescence microscopy assay or western blot analysis. The results showed that LDH concentration, EMPs numbers, and the expression of proinflammatory cytokines (IL-6, IL-8, and IL-1β) increased in TNF-α-induced injured HUVECs, but ameliorated by BBR pretreatment. BBR pretreatment upregulated the expression of phosphorylated AMPK and downregulated the expressions of NF-κB and YY1 in injured HUVECs induced by TNF-α, which were offset by the AMPK inhibitor Compound C (CC). The results indicated that BBR protected against TNF-α-induced endothelial injury via the AMPK/NF-κB/YY1 signaling pathway.

The traditional pretreatment leads to the recalcitration of C-C bonds during lignin fractionation, thus hindering their depolymerization into aromatic monomers. It is essential to develop an applicable approach to extract noncondensed lignin for its high-value applications. In this work, noncondensed lignins were extracted from poplar sawdust using recyclable

Breast cancer is the most common malignant disease in women worldwide. Early diagnosis and treatment can greatly improve the management of breast cancer. Liquid biopsies are becoming convenient detection methods for diagnosing and monitoring breast cancer due to their noninvasiveness and ability to provide real-time feedback. A range of liquid biopsy markers, including circulating tumor proteins, circulating tumor cells, and circulating tumor nucleic acids, have been implemented for breast cancer diagnosis and prognosis, with each having its own advantages and limitations. Circulating extracellular vesicles are messengers of intercellular communication that are packed with information from mother cells and are found in a wide variety of bodily fluids; thus, they are emerging as ideal candidates for liquid biopsy biomarkers. In this review, we summarize extracellular vesicle protein markers that can be potentially used for the early diagnosis and prognosis of breast cancer or determining its specific subtypes.

An 8-year-old girl presented to our hospital with chest tightness, fatigue, and discomfort after exercise. A radiograph indicated a large heart shadow. Overt ventricular pre-excitation was noted on...

Selective saccharification of cellulose into glucose is a critical step for utilization of lignocellulosic biomass. Molten salt hydrates (MSHs) have shown promising performance in selectively converting cellulose into glucose because of the high solubility of cellulose in the solvent. However, the separation of formed glucose from the MSHs is still a grand challenge. To address this issue, we developed a two-step process, where crystalline cellulose is hydrolyzed into short-chain glucan oligomers in MSHs followed by separation and subsequent hydrolysis of the formed oligomers into glucose under mild conditions. The two-step method provides an easy separation for glucan oligomers from the MSHs without sacrificing the selectivity to glucose. Application of the method for crystalline cellulose is, however, limited to a relatively low concentration, 26.2 mg/mL, because of the formation of byproducts in the MSH that facilitate oligomers degradation. In this work, reactive adsorption was employed to in situ remove the byproducts formed during cellulose hydrolysis in the MSH. It was found that hyper-cross-linked polymer (HCP) made from the polymerization of 4-vinylbenzyl chloride and divinylbenzene can selectively adsorb 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) while showing negligible sugar adsorption in both water and the MSH. With the reactive adsorption approach, byproducts including 5-HMF and LA were removed from the reaction media under reaction conditions, and their negative effects on oligomer degradation were inhibited. In the presence of the HCP, the obtained glucan oligomer concentration was enhanced from less than 54.2 to 247.1 mg mL-1 when the weight ratio of cellulose was increased to MSH from 1:60 to 1:4, exhibiting an oligomer yield of 69.5%. The HCP can be effectively separated from the reaction media by filtration and regenerated by oxidation with hydrogen peroxide. Application of reactive adsorption with HCP for cellulose hydrolysis in the MSH provides a promising method to produce glucan oligomers and glucose with an improved yield and efficiency.

The patients of Inflammatory bowel disease (IBD) are increasing worldwide. IBD has the characteristics of recurring and difficult to cure, and it is also one of the high-risk factors for colorectal cancer (CRC). The occurrence of IBD is closely related to genetic factors, which prompted us to identify IBD-related genes. Based on the hypothesis that similar diseases are related to similar genes, we purposed a SVM-based method to identify IBD-related genes by disease similarities and gene interactions. One hundred thirty-five diseases which have similarities with IBD and their related genes were obtained. These genes are considered as the candidates of IBD-related genes. We extracted features of each gene and implemented SVM to identify the probability that it is related to IBD. Ten-cross validation was applied to verify the effectiveness of our method. The AUC is 0.93 and AUPR is 0.97, which are the best among four methods. We prioritized the candidate genes and did case studies on top five genes.

Plant growth-promoting rhizobacteria (PGPR) are a functionally diverse group of microbes having immense potential as biostimulants and biopesticides. We isolated four PGPR (designated n, L, K, and Y) that confer growth-promoting effects on Arabidopsis thaliana. The present study describes the detailed polyphasic characterization of these PGPR. Classical methods of bacterial identification and biochemical test kits (API20E, API20NE, API ZYM, and API 50CH) revealed their metabolic versatility. All rhizobacterial isolates were positive for 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCD) and indole acetic acid production and phosphorous solubilization. PCR analysis confirmed the presence of the nifH gene in strains n, L, and Y, showing their N2-fixation potential. In vitro dual culture methods and bacterial infestation in planta demonstrated that strains n and L exerted antagonistic effects on Pseudomonas syringae pv. tomato DC3000 and Botrytis cinerea 191 and provided protection to Arabidopsis plants against both phytopathogens. Short- or long-term bacterial treatment revealed significant changes in transcript levels of genes annotated to stress response and hormone metabolism in A. thaliana. In particular, the expression of stress-responsive genes in A. thaliana showed an upregulation under salinity stress. MAP kinase 6 (MPK6) was involved in the growth promotion induced by the four bacterial strains. Furthermore, these strains caused a significant increase in root dry weight of maize seedlings under gnotobiotic conditions. We conclude that the four rhizobacteria are good candidates as biofertilizers for enhancing growth of maize, among which strains n and L showed marked plant growth-promoting attributes and the potential to be exploited as functional biostimulants and biopesticides for sustainable agriculture. IMPORTANCE There are pressing needs to reduce the use of agrochemicals, and PGPR are receiving increasing interest in plant growth promotion and disease protection. This study follows up our previous report that the four newly isolated rhizobacteria promote the growth of Arabidopsis thaliana. We test the hypothesis that they have multiple PGP traits and that they can be used as biofertilizers and biopesticides. In vitro assays indicated that these four strains have various PGP properties related to nutrient availability, stress resistance, and/or pest organism antagonism. They significantly influenced the transcript levels of genes involved in stress response and hormone metabolism in A. thaliana. MPK6 is indispensable to the growth stimulation effects. Strains n and L protected A. thaliana seedlings against phytopathogens. Three strains significantly increased maize growth in vitro. In summary, introducing these four strains onto plant roots provides a benefit to the plants. This is the first study regarding the potential mechanism(s) applied by Mucilaginibacter sp. as biostimulants.

With the development of “internet plus”, big data and artificial intelligence, “cloud teaching” has become the inevitable trend of informational teaching reform. How to correctly carry out “cloud teaching” based on the traditional teaching mode has become a problem worth thinking about. This paper makes explanation on the process design of “Cloud Teaching” for the “Financial and Business Integration” course in three parts: the practical content, course assessment and course management. This paper aims putting forward some suggestions to how to build courses in the information platform and receive good evaluation.

Objective High-dose intravenous vitamin C (HIVC) is a major concern when treating patients with coronavirus disease 2019 (COVID-19). The aim of this study was to assess the clinical efficacy of HIVC on hyperinflammation in patients with severe COVID-19. Methods This retrospective cohort study included hospitalized patients with severe COVID-19, a subset of whom was treated with HIVC. The medical records were screened for demographic data, laboratory findings, and medications, as well as initial and repeated values of multiple inflammatory markers for analysis. Results A high percentage of patients presented with hyperinflammation based on inflammatory marker levels above the upper limit of normal (high-sensitivity C-reactive protein, 80.1%; interleukin-6, 91.5%; and tumor necrosis factor-α, 67.4%). Eighty-five (36%) patients received HIVC therapy. After treatment with HIVC, the levels of inflammatory markers displayed a significant decrease compared with those of patients without HIVC. Furthermore, the percentages of reduction in inflammatory marker levels were higher in patients receiving HIVC compared with those in patients treated without HIVC. Stepwise multiple linear regression analysis revealed that HIVC was independently associated with percentages of reduction in levels of inflammatory markers. Conclusions HIVC has the potential benefit of attenuating hyperinflammation by reducing inflammatory marker levels in patients with severe COVID-19.

PurposeThe purpose of this paper is to examine the influence of human resource management (HRM) reforms on job-related well-being of academics in Chinese universities. It also tests the mediating effect of work intensification (WI) and affective commitment (AC), and the moderating effect of perceived organizational justice (OJ) on the HRM‒well-being relationship to understand the influence mechanisms and boundary conditions.Design/methodology/approachA questionnaire survey was conducted in 25 Chinese universities, obtaining 638 usable questionnaires. Structural equation modeling (SEM) was used as the analytical technique to examine the model fit and test hypotheses.FindingsThe findings reveal that the relationship of HRM and well-being is neither direct nor unconditional, and a win‒win scenario for both management and employee well-being is possible when organizations pursue HRM innovations.Research limitations/implicationsThe limitations of this study are that data were collected at once and at a defined time, with no time lag being involved. In addition, all variables were self-reported.Practical implicationsCommitment-oriented HRM practices can create a win‒win scenario; when control-oriented HRM practices are necessary, managers should ensure OJ to offset their negative influence on employees.Originality/valueThis study is among the first to examine the impact of HRM on employee well-being in the context of Chinese higher education, contributing to the limited studies on HRM in Chinese public sector and the on-going debate on the nature of HRM in China.

The concentrations and carbon isotopic (13C, 14C) compositions of total organic carbon (TOC) and black carbon (BC) were measured for four sediment cores collected from the shelf to slope in the Arctic Ocean. Contents of TOC and BC ranged from 0.46% to 1.94% and 0.04% to 0.13% by dry weight, and BC accounted for 3.5% to 15.2% of the TOC preserved in the shelf and slope sediments. Sediment of the Chukchi shelf contained relatively high BC contents compared with the sediments of the Arctic slope, suggesting strong influence from the river and terrestrial inputs to the shelf region. Radiocarbon measurements revealed that the ages of BC are in the range of 7330 to 29,700 years (before present) and they are 4093 to 7723 years older than the 14C ages of TOC preserved in the same sediment depths. Based on an isotopic mass balance model, we calculated that fossil fuel combustion contributed 62–96%, and biomass burning contributed 4–38% of the BC pool in the sediments of the study area. This “slow-cycling” old BC is an important fraction of the inert organic carbon pool preserved in the sediments, and represents a significant sink of atmospheric CO2 and global carbon cycle. With the thawing permafrost caused by continuous global warming, the size of this BC pool mobilized and exported by rivers to the Arctic Ocean could increase in the future.

Bcl6, a critical pro-oncogene of human B-cell lymphomas, can promote tumor progress. Previous studies have found that Bcl6 participates in hypoxia injury in cardiomyocytes. However, the effect of Bcl6 on cardiac fibroblasts is still unclear. The aim of this study was to elucidate the functional role of Bcl6 in cardiac fibroblast activation and function. The neonatal rat cardiac fibroblasts were isolated and cultured. First, transforming growth factor ß1 (TGFß1) was used to stimulate fibroblast activation. A decreased expression level of Bcl6 was observed in fibroblasts after stimulation with TGFß1. Then, cells were transfected with adenovirus Bcl6 to overexpress Bcl6. The results showed that Bcl6 overexpression induced decreased proliferation and reduced activation of fibroblasts which were stimulated with TGFß1. It was found that activated smad2 and smad3 were not changed by overexpressing Bcl6, but smad4 was decreased. Furthermore, co-immunoprecipitation results showed that Bcl6 directly bound to smad4, and induced down-regulation of smad4. At last, smad4 activator could counteract the anti-fibroblast effects of Bcl6. In conclusion, Bcl6 may negatively regulate cardiac fibroblast activation and function by directly binding to smad4.

Entrepreneurs’ subjective wellbeing has become an important topic in research: entrepreneurs undertake risks and create their companies seeking personal satisfaction and fulfillment. As a r...

Cornstalk cellulose was liquefied in supercritical acetone at various temperature by a high-pressure autoclave, where the maximum yield of bio-oil was 43.79% and the highest conversion rate of cellulose was 72.13%. FT-TR spectrums showed that the C–O–C and C–C bonds in cellulose were cleaved under the attack of supercritical acetone, then active fragments were produced and transformed into liquefaction products. GC-MS results showed that the dominant components in bio-oil were ketones, esters, alkanes, etc. As the acetone dosage increased, ketones and glucosides increased while esters and alkanes decreased. A higher temperature was suitable for ketones and esters formation, which had an inhibition on alkanes formation. Finally, the formation of pathways and networks of dominant chemicals during cellulose liquefaction in supercritical acetone were developed. This investigation contributes to the knowledge of cellulose liquefaction in supercritical solvents for bio-oil and platform chemicals, which can provide an alternative method for biomass resources utility.

Deep learning is a hot method in face super-resolution reconstruction in recent years, but it needs to further improve the details of reconstructed images and speed up network training. This paper improves the deep residual network from two aspects of residual unit and network structure and proposes a face super-resolution reconstruction algorithm based on the improved model. We improve the network structure of the residual unit by connecting with a densely connected convolutional layer and removing the BN layer, thereby enhancing the information flow between the inner convolutional layers and eliminate the damage to the spatial information of the image by batch normalization processing. At the same time, we combine the output characteristics of each residual unit on the basis of the global residual structure, so the face feature information is more fully utilized and the model detail recovery ability is also improved. Experiments on FDDB and AFLW face datasets show that the proposed method has better performance in feature description and detail information reconstruction, and higher PSNR and SSIM than other methods.

While it is widely recognised that an asset-augmenting rather than asset-exploiting strategy drives emerging multinationals’ (EMNEs) internationalization, current research focuses on the motivations behind knowledge seeking FDI. What remains less clear is why latecomer firms can engage in learning in advanced countries. Conjoining the “Linkage-Leverage-Learning (LLL)” framework and knowledge seeking literature, this study shows how Chinese investment in the European Union reveals the preconditions for foreign knowledge sourcing. We follow a set-theoretic approach, utilizing fuzzy-set qualitative comparative analysis (fsQCA), to identify equifinal configurations of linkage and leverage conditions leading to high learning propensity of EMNEs. Our analysis extends the LLL framework and complements the recent debate on the theory of the EMNE. We develop propositions based on distinct constellations of learning antecedents.

The effects on plants of commercial applications of biofertilizer and biocontrol agents containing planktonic rhizobacteria cells are inconsistent mainly due to an unsuccessful competition with existing endogenous microbial communities. The present study investigated rhizobacteria inoculants in the form of biofilms, which are dense colonies of single or multi-species microbial cells, adherent to either biotic or abiotic surfaces, and encased in a self-produced matrix composed of extracellular polymeric substances. Bacillus sp., Pseudomonas sp., or a mixed inoculum of both bacteria at the planktonic or biofilm stage of growth were applied to greenhouse-grown tomato (Solanum lycopersicum L. cv Trust) plants fertilized with a half strength Hoagland solution or a modified solution lacking phosphate or iron. Based on multivariate analysis of variance, availability of nutrients, bacteria, and stages of bacterial growth significantly affected plant variables known to be contributing factors to greenhouse tomato yield. Results suggest that Bacillus sp. and Pseudomonas sp. biofilms are more effective inoculants than planktonic bacteria cells. Pseudomonas sp. applied as a biofilm increased the height and root dry weight of tomato plants, but it inhibited the positive effects of inoculation on tomato leaf number and tomato root length. Path analysis identified positive causal paths from (Pseudomonas) biofilm and planktonic cells, to the tomato plant growth variables. Presence of Bacillus sp. alone or in a mixture inhibited the positive effects of inoculation on tomato plant leaf area and root dry weight. Nevertheless, the effect of Bacillus sp. on root length was relatively positive. Results suggest that the use of innovative rhizobacteria biofilm technologies could prove advantageous as biofertilizer agents, and alleviate the dependence of greenhouse tomato producers on non-biological agro-chemicals.

The poor prognosis of patients with acute myocardial infarction is partially attributed to a large number of cardiomyocyte apoptosis, necrosis, limited cardiac healing and angiogenesis, and cardiac dysfunction. Immune cells dysfunction leads to nonhealing or poor healing of wounds after acute myocardial infarction. Toll-like receptor 9 (TLR9) as an essential part of the innate immune system plays a vital role in regulating cardiomyocyte survival and wound healing. During hypoxia, High Mobility Group Box 1 (HMGB1), as the typical damage-associated molecular patterns (DAMPs) or alarmin, is rapidly released extracellularly and translocates from the nucleus to bind with cytoplasmic TLR9. However, the mechanism by which TLR9 interacts with HMGB1 and regulates myocardial damage remains unclear. Our current study found that the survival rate of TLR9KO mice with a higher rate of cardiac rupture was significantly lower than that in WT mice after 28 days post-operation. The effect of TLR9 knockout on insufficient wound healing in experimental MI was caused by a diminished number of myofibroblast and defective matrix synthetic capability. Moreover, the increased myocardial apoptotic cells and decreased angiogenic capacity were found in TLR9 knockout mice after MI. The results showed contrary in Recombinant Human High Mobility Group Box 1 (rhHMGB1) treated WT mice and similarity after applying rhHMGB1 in TLR9KO mice. This study demonstrates that TLR9 is essential for the repair of infarcted myocardium and interaction of HMGB1 and TLR9 is involved in the survival of myocardial cells, wound healing, and angiogenesis after myocardial infarction.

The secondary cell wall is an important carbon sink in higher plants and its biosynthesis requires coordination of metabolic fluxes in the phenylpropanoid pathway. In Arabidopsis (Arabidopsis thaliana), MYB75 and the KNOX transcription factor KNAT7 form functional complexes to regulate secondary cell wall formation in the inflorescence stem. However, the molecular mechanism by which these transcription factors control different branches of the phenylpropanoid pathway remains poorly understood in woody species. We isolated an R2R3-MYB transcription factor MYB6 from Populus tomentosa and determined that it was expressed predominately in young leaves. Overexpression of MYB6 in transgenic poplar upregulated flavonoid biosynthetic gene expression, resulting in significantly increased accumulation of anthocyanin and proanthocyanidins. MYB6-overexpression plants showed reduced secondary cell wall deposition, accompanied by repressed expression of secondary cell wall biosynthetic genes. We further showed that MYB6 interacted physically with KNAT7 and formed functional complexes that acted to repress secondary cell wall development in poplar and Arabidopsis. The results provide an insight into the transcriptional mechanisms involved in the regulation of the metabolic fluxes between the flavonoid and lignin biosynthetic pathways in poplar.

A series of orange-red phosphors NaGd1-x(MoO4)(WO4):xSm3+ (x = 0.01, x = 0.02, x = 0.03, x = 0.04, x = 0.05 and x = 0.06) were prepared by a high temperature solid state reaction in air atmosphere. X-ray diffraction, photoluminescence (PL) spectra and fluorescent thermal stability analysis were utilized to characterize the structure and luminescence properties of as-prepared phosphors. The chromaticity coordinates of the samples were calculated and located in the orange-red region. These phosphors possessed scheelite tetragonal crystal structure with a space group of I41/a. Upon excitation at 406 nm, the emission peaks at 564 nm (4G5/2 → 6H5/2), 600 nm (4G5/2 → 6H7/2), 646 nm (4G5/2 → 6H9/2) and 700 nm (4G5/2 → 6H11/2) transitions of Sm3+ were observed. The optimum doping concentration of Sm3+ ions in NaGd1-x(MoO4)(WO4):xSm3+ was x = 0.03. The energy transfer mechanism between the Sm3+ ions was confirmed as dipole–dipole interaction and the critical distance was obtained to be 21.59 A. Compared with NaGd0.97(MoO4)2:0.03Sm3+, the fluorescence thermal quenching temperature of NaGd0.97(MoO4)(WO4):0.03Sm3+ increases from 398 K to 473 K, which preformed higher thermal stability and emitting-color stability, and shows a great potential for its application in LEDs as a suitable orange-red-emitting phosphor.

Through C–O–Mn bonding, graphene nanosheets are homogeneously dispersed in porous Mn3O4 to take full advantages of porous Mn3O4 and graphene nanosheets, making the as-formed three-dimensional porous Mn3O4/reduced graphene oxide (rGO) composite exhibit good electrochemical performance. Besides, C–O–Mn bonding is demonstrated to greatly promote the Faradic reactions of the composite, resulting in the enhancement of its real capacity in supercapacitor (SC) electrodes as well as lithium-ion battery (LIB) anodes. By simply fine-tuning the content of graphene (

Cardiac remodeling is associated with inflammation and apoptosis. Galangin, as a natural flavonol, has the potent function of regulating inflammation and apoptosis, which are factors related to cardiac remodeling. Beginning 3 days after aortic banding (AB) or Sham surgery, mice were treated with galangin for 4 weeks. Cardiac remodeling was assessed according to echocardiographic parameters, histological analyses, and hypertrophy and fibrosis markers. Our results showed that galangin administration attenuated cardiac hypertrophy, dysfunction, and fibrosis response in AB mice and angiotensin II‐treated H9c2 cells. The inhibitory action of galangin in cardiac remodeling was mediated by MEK1/2–extracellular‐regulated protein kinases 1/2 (ERK1/2)–GATA4 and phosphoinositide 3‐kinase (PI3K)–protein kinase B (AKT)–glycogen synthase kinase 3β (GSK3β) activation. Furthermore, we found that galangin inhibited inflammatory response and apoptosis. Our findings suggest that galangin protects against cardiac remodeling through decreasing inflammatory responses and apoptosis, which are associated with inhibition of the MEK1/2–ERK1/2–GATA4 and PI3K–AKT–GSK3β signals.

Aiming at improving time delay estimation (TDE) in the case of single sensor, a novel method of constructing virtual sensor array is presented, and furthermore the MUSIC delay estimation algorithm based on the virtual array is proposed. The approach and complete procedure of the algorithm are given. The relationship between the number of virtual array elements and the constructed signal is studied, and the method of determining the minimum number of elements under the condition of estimation time delay accurately is given. The simulation experiments of the presented algorithm have been carried out from three angles of view. The least virtual array elements and the minimum subspace dimensions needed in this algorithm is verified. We obtained the performance of time delay estimated by the algorithm under sparse path and dense path conditions respectively. This paper also illustrated the high precision and high-resolution characteristics of the proposed method.

Aiming at the copyright protection of digital works, a blind watermarking algorithm in Contourlet domain based on adaptive quantization is proposed. The algorithm adaptively regulates quantization step size in the Contourlet domain according to the mean of each sub block, so that the embedding strength of watermark can better adapt to the characteristics of each sub block. Before extracting watermark, the rotation correction algorithm has been applied in processing image, which greatly improves the ability of blind watermarking algorithm to resist rotation attacks. Many anti attack experiments are carried out on the proposed algorithm. The results show that the algorithm has good robustness, and it has distinctness advantages in anti JPEG compression, Gauss noise, shear and rotation attack.

The reclamation is the main method in the coast exploitation, and the assessment of the hydrodynamic environment effect of the reclamation project is important for project’s site selection and environmental protection. With consideration of the baroclinic water, a 3-D numerical model MIKE3 is applied to simulate Yangtze Estuary’s hydrodynamic environment to predict the impacts of the reclamation project of the Nanhui tidal flat. The simulated results of the model agree well with the field data of the tide level, the current speed, the current direction, the temperature, the salinity and the water quality, and it is indicated that after the reclamation project, the high tide level will be lower, while the low tide level will be higher in the South Branch in general. During the spring tide in the dry season, the peak velocity during the ebb tide in the North Channel will be reduced by 13%, while it will be increased by 21% in the South Channel in average. The salinity will be increased in the North Channel, while reduced in the South Passage, besides, the reclamation project will aggravate the saltwater intrusion of the North Branch. The value of N/P will be increased by about 4% in the whole South Branch except for the North Channel, leading to a slight aggravation of the phosphorus restriction effect in the Yangtze Estuary.

Shaft sinking by drilling is widely used in mining, construction and coal industry. Measuring the shaft borehole accurately, is of great importance to the quality in these projects among other factors. This paper proposes a novel design and implementation of ultrasonic logging instrument for shaft sinking by drilling (ULISSD). Design of the ultrasonic ranging module, depth module and the module for downhole orientation, as well as the borehole radius measurement algorithm are explained and illustrated. This paper also demonstrates an experimental application of ULISSD, which shows that, compared with other similar instruments, ULISSD is able to measure accurately borehole shaft radius wider diameters (3–12 m) at deeper vertical sections (maximum 1000 m) in slurry with higher gravity (≤ 1.22).

Machine learning has shown its great potential in the accelerated discovery of advanced materials in the field of computational molecular design. High-temperature polymer dielectrics are urgently required with the emerging applications of energy-storage dielectric film capacitors under high-temperature conditions. Here, we demonstrate the successful prediction of polymers with a high dielectric constant ( ɛ) and high glass transition temperature ( Tg) using a Bayesian molecular design model. The model is trained on a joint data set containing 382 computed ɛ values using density functional perturbation theory and experimentally measured Tg values of ∼7000 polymers to build relative quantitative structure–property relationships and identify the promising polymers with specific desired range of dielectric constant and glass transition temperature. From the hypothetical polymer candidates, ten promising polymers are proposed based on their predicted properties and synthetic accessibility score for high-temperature dielectric film capacitors’ application. Moreover, 250k novel polymer structures are generated with the model to support future polymer informatics research. This work contributes to the successful prediction of high-temperature polymer dielectrics using machine learning models.

Embracing a mutual-benefit perspective of expatriation management, this study argues that multinational enterprises (MNEs) seeking to build a sustainable expatriation management system should address the goals of both expatriates and organisations simultaneously. To realize such a system, we propose ability-, motivation- and opportunity-attributes as a tripod of expatriate competence-enhancing practices (EC-Ps). Via a matched survey dataset from 150 expatriates and their headquarters (HQs) managers, this study (1) investigates the effects of implementing EC-Ps on both subsidiary and employee outcomes, and (2) explores a sequential mediation mechanism of cross-cultural competence and subsidiary autonomy between the relationships. The implications of the findings for theory and practice are discussed.

Evidence has shown that stressful life events are associated with sleep quality, yet studies on employees are scarce. In the present study, we explored the association between stressful life events and sleep quality in Chinese governmental employees. The cross-sectional data on 10,994 Chinese governmental employees aged 20-60 years were derived from a cohort study on chronic diseases of governmental employees in Hunan Province, China. Logistic regression models were used to calculate the adjusted odds ratio (OR) and the 95% confidence interval (CI). Of the participants, 3517 (32.0%) reported poor sleep quality in the past month. Participants who experienced more than two life events in the past year were associated with 3 times (OR: 3.681, 95%CI:3.287-4.123) greater likelihood of poor sleep quality. Negative life events, but not positive life events, were significantly associated with poor sleep quality. Regarding the types of events, economic-related life events were associated with poor sleep quality only in employees aged 20-35 years. Regarding the specific life events, work stress, job dissatisfaction, pregnancy or wife pregnancy,quality in Chinese governmental employees. discord with spouse's parents, separation from spouse due to work, bad relationship between spouse, unsatisfied sex life, misunderstood, blamed, false accusation or argument, and lifestyle changes were significantly associated with poor sleep quality. When stratified by sex, age and occupational position, the association of specific events and sleep quality were different. The present study showed that cumulative life events, negative life events and several specific events were significantly associated with poor sleep quality on Chinese governmental employees.

To compare accuracy of anterior cervical pedicle screws between assist of rapid prototyping 3D guide plate and free-hand insertion, and evaluate the safety of two methods.Eight adult cervical cadaver specimens after formaldehyde immersion, including 4 males and 4 females, aged 32 to 65(40.3±5.6) years old. After X-ray examination to exclude bone damage and deformity, 4 of them (3D guide plate group) randomly selected were for CT scan to obtain DICOM format data, and the data was imported into Mimics software for model, designed the ideal entry point and nail path for anterior cervicaltranspedicular screw (ATPS). After obtaining the personalized guide plate of the nail channel, it was exported as STL data, and the individual guide plate was printed by rapid prototyping and 3D printing technology. In turn, with the assistance of 3D guide plates, one-to-one personalized ATPS screws were placed on the four lower cervical cadaver specimens. Another 4 (free-hand group) lower cervical cadaver specimens were implanted with ATPS screws using free-hand technique. All specimens were performed CT thin-layer scanning and three-dimensional reconstruction after operation. The Tomasino method was used to evaluate the safety of the screws on the CT cross-sectional and sagittal images, to determine whether there was a cortical puncture of the lower and inner edges of the pedicle. According to the CT rating results, gradeⅠandⅡwere safe, and grade Ⅲ- Ⅴ were dangerous.And the accuracy of screws was recorded and analyzed between two groups.Two screws were inserted in each segment from CThe 3D printing rapid prototyping guide plate assisted insertion of the anterior cervical pedicle screw can significantly improve the accuracy and safety, and provide a theoretical basis for further clinical application.

Background: Cardiac injury is common and associated with worse clinical outcomes in COVID-19. Data are lacking whether high-dose intravenous vitamin C (HIVC) could help to improve cardiac injury in the pandemic. Methods: The study included severe and critically ill COVID-19 with cardiac injury. Troponin I and inflammatory markers were collected at admission and 14 days after treatment with HIVC along with symptomatic supportive treatment from the electronic medical records. Results: The patients (n = 113) were categorized into the improved cardiac injury (ICI) group (n = 70) and the non-improved cardiac injury (NICI) group (n = 43). Overall, 51 (45.1%) patients were administrated with HIVC, the percentages of patients with HIVC were higher in the ICI group than those in the NICI group. Logistic regression analysis revealed that HIVC was independently associated with improved cardiac injury. Further analysis showed that inflammatory markers levels significantly decreased at 14 days after treatment with HIVC compared to those without HIVC. Meanwhile, similar results were also observed regarding changes in inflammatory markers levels from baseline to 14 days after treatment with HIVC. Conclusions: HIVC can improve cardiac injury through attenuating hyperinflammation in severe and critically ill patients with COVID-19.

Cardiac hypertrophy is the uppermost risk factor for the development of heart failure, leading to irreversible cardiac structural remodeling and sudden death. As a major mediator of cardiac remodeling, oncostatin M (OSM) and its receptor, OSMR, attract plenty of interest. Recent studies have demonstrated key effects of noncoding RNAs on myocardial remodeling. However, whether noncoding RNAs that regulate the expression of OSMR would regulate the process of remodeling remain unclear. Herein, we observed that long noncoding RNA (lncRNA) Pvt1 expression showed to be significantly elicited by aortic banding (AB) operation in vivo and by angiotensin (Ang II) treatment in vitro. Pvt1 knockdown significantly attenuated the myocardial hypertrophy caused by pressure overload within rats and the cardiac myocyte hypertrophy caused by Ang II in vitro. Moreover, Pvt1 knockdown also decreased cellular myomesin and B-raf, which was involved in OSM function in cardiac remodeling. Based on online tools prediction, miR-196b may simultaneously target Pvt1 and OSMR 3' untranslated region (UTR). In rat H9c2 cells and primary cardiac myocyte, Pvt1 and miR-196b exerted negative regulatory effects on each other and miR-196b negatively regulated OSMR expression. Pvt1 directly targeted miR-196b to relieve miR-196b-induced OSMR suppression via acting as a competing endogenous RNA (ceRNA). Moreover, the effect of miR-196b suppression upon the B-raf was opposite to Pvt1 knockdown, and miR-196b suppression might significantly attenuate the effect of Pvt1 knockdown. In summary, Pvt1/miR-196b axis modulating cardiomyocyte hypertrophy and remodeling via OSMR. Our findings provide a rationale for further studies on the potential therapeutic benefits of Pvt1 function and mechanism in cardiac and cardiomyocyte hypertrophy by a lncRNA-miRNA-mRNA network.