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The (AlCoCrFeNi)1-X (WC-10Co)X composite coatings were fabricated on 06Cr13Ni5Mo steel by high-velocity oxygen-fuel (HVOF) spraying. The coatings' microstructure, mechanical properties, and corrosion performance were characterized, and the cavitation erosion resistance of the coatings was tested in 3.5 wt% NaCl medium. The influence of the microstructure, mechanical properties, and corrosion resistance on cavitation erosion resistance were discussed. The microhardness and local plastic deformation resistance of the coatings were increased by WC-10Co, while the corrosion resistance of the composite coatings was decreased by severe galvanic corrosion. The cavitation erosion mechanism of the coatings was lamellar spalling. In NaCl medium, the (AlCoCrFeNi)75(WC–10Co)25 (HEA75/WC25) coating showed lower cavitation erosion resistance than the AlCoCrFeNi (HEA) coating, which was caused by the galvanic corrosion, uncoordinated deformation and the low bonding strength of the HEA/WC-10Co interface. For the HEA75/WC25 coating and (AlCoCrFeNi)50(WC–10Co)50 (HEA50/WC50) coating, the cavitation erosion damage of the HEA75/WC25 coating was higher than that of the HEA50/WC50 coating. When the microstructure and corrosion resistance of the coatings were similar, the cavitation erosion resistance was mainly affected by the mechanical property.

The (AlCoCrFeNi)1-X(WC-10Co)X composite coatings were fabricated by HVOF spraying and their microstructures, mechanical properties and cavitation erosion behaviors were tested. The effects of WC-10Co on the cavitation erosion mechanisms were discussed by compared the differences of volume losses and eroded surface morphologies between the coatings. The cavitation erosion resistance of the coatings was about 3 times as that of the 06Cr13Ni5Mo steel. With the addition of WC-10Co, the cavitation erosion resistance of the coating was slightly increased. In the initial stage of cavitation erosion test, the cavitation erosion damage was concentrated on the interface, which was caused by the uncoordinated deformation and poor mechanical properties of the interface between HEA and WC-10Co. When the WC-10Co distributed below the HEA region, the WC-10Co played a strong supporting role and improved the impact resistance of the HEA region. The cavitation erosion mechanism of the HEA1 coating was lamellar spalling. The cavitation erosion mechanisms of the HEA2 and HEA3 coatings were particles spalling and lamellar spalling.

The literature has indicated that personal relative deprivation (PRD) results in anxiety disorders. Given that some cognitive models propose that attention bias toward a threat causes and maintains anxiety, relatively deprived individuals may have difficulty gating threat from working memory. To test this hypothesis, this study investigated the influence of PRD on the filtering ability of happy, angry, and neutral facial distractors from visual working memory using electroencephalography (EEG). Participants were randomly assigned to a PRD (n = 24) or a non-PRD group (n = 24). Filtering ability was reflected by comparing the contralateral delay activity (CDA) amplitude for one-target, one-target-one-distractor, and two-targets conditions. The CDA was measured as the difference in mean amplitudes between activity in the hemispheres contralateral and ipsilateral to the to-be-remembered information. Results indicated that individuals in the PRD group showed a reduced ability to filter out neutral and angry facial distractors, as reflected by similar CDA amplitudes for one-target-one-distractor and two-targets conditions for both angry and neutral distractors in the PRD group. However, PRD did not impair the ability to filter out happy facial distractors, as reflected by similar CDA amplitudes for one-target-one-distractor and one-target conditions for happy distractors in the PRD group. As neutral faces might then be taken as potentially threatening information by relatively deprived individuals, these results support the hypothesis that relatively deprived individuals might have difficulty filtering out threat-related information.

To compare the effects of Liuzijue Qigong and conventional respiratory training on trunk control ability and respiratory muscle functions in patients at an early recovery stage from stroke.A single-blind, randomized controlled trial.A hospital.Patients (N=60) within 2 months poststroke.The experimental group (n=30) received conventional rehabilitation training combined with Liuzijue exercise, and the control group (n=30) received conventional rehabilitation training combined with conventional respiration training. The training in the 2 groups was conducted 5 times per week for 3 weeks.Trunk Impairment Scale (TIS), maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF), maximum expiratory mid-flow (MMEF), diaphragmatic movement, the change of intra-abdominal pressure (IAP), Berg Balance Scale (BBS), and Modified Barthel Index (MBI). All outcome measures were assessed twice (at baseline and 3 weeks).Both groups significantly improved in TIS, MIP, FVC, PEF, and the change of IAP, BBS, and MBI when pre- and postassessments (P.05) were compared. Compared with the control group, there was a significant difference in the experimental group in the static sitting balance subscale (P=.014), dynamic balance subscale (P=.001), coordination subscale (P.001), TIS total scores (P.001; effect size [ES]=0.9), MIP (P=.012; 95% confidence interval [CI], 2.23-17.69; ES=0.67), MEP (P=.015; 95% CI, 1.85-16.57; ES=0.65), change of IAP (P=.001), and MBI (P=.016; 95% CI, 1.51-14.16; ES=0.64). No significant differences were found between the 2 groups in FEV1 (P=.24), FVC (P=.43), PEF (P=.202), MMEF (P=.277), the diaphragmatic movement of quiet breathing (P=.146), deep breathing (P=.102), and BBS (P=.124).Liuzijue exercise showed more changes than conventional respiratory training in improving trunk control ability, respiratory muscle functions, and activities of daily living ability in patients at an early recovery stage from stroke.

This study proposes an enhanced multipath mitigation method based on multi-resolution carrier-to-noise-ratio (CNR) model and adaptive statistical test strategy for real-time kinematic precise point positioning (PPP) applications. The multi-resolution CNR model is established with GPS observation data collected from DOY 152 to 181 of 2019 by 230 globally distributed IGS stations, which used to analyze the relevant factors affecting CNR. Statistical results indicate that the CNR is not only related to the satellite elevation, but also closely related to the receiver types and specific satellite. The maximum difference between different receivers can reach 20 dB for the same satellite at the same elevation. In addition, the performance of the CNR is also obviously different between each satellite, and the maximum difference between different satellites is about 10 dB for the same receiver at the same elevation. Hence, in terms of the method which is based on CNR information for multipath detection and mitigation, the independence of receiver types, satellite and frequency must be considered. With the above analysis, this study developed a multi-resolution CNR model based on different receiver types, different satellites and different elevation firstly. Then, combined with the adaptive statistical test strategy which is based on the difference of CNR between inter-frequency and the difference of CNR between adjacent epochs, the multipath can be detected effectively. For the epoch which affected by multipath, the down-weighted strategy based on CNR is adopted to mitigate the influence of multipath on positioning. Real-time kinematic PPP data are collected to assess the proposed method, and the results demonstrate that the proposed method can detect the multipath effectively, and the detection rate can reach 90.28%. Moreover, after adopting the mitigation strategy, the RMS bias of the east, north and up components are improved about 19.95%, 17.89% and 23.07% compared to the original results, respectively. It is worth noting that this proposed method is also suitable for other GNSS, such as GLONASS and BDS, but the corresponding CNR model must be established simultaneously.

In this study, three kinds of WC-based cermet coatings including WC–CoCr coating, WC–Ni coating and WC–Cr3C2–Ni coating were prepared by the high-velocity oxygen-fuel (HVOF) spraying process. Scanning electron microscopy (SEM), energy disperse spectroscopy (EDS) and Vickers hardness tester were used to analyze the microstructure and mechanical properties of these coatings. The WC–CoCr coating presented the highest average microhardness of 1205 HV0.3, and then followed by the WC–Cr3C2–Ni coating (1188 HV0.3) and the WC–Ni coating (1105 HV0.3). The abrasive wear behavior of the WC-based coatings under the conditions of different applied loads and sediment concentrations were studied by a wet sand-rubber wheel tester. The results indicated that the abrasive wear loss rates of all the coatings increased with the increment of applied load or sediment concentration. In addition, the coatings with higher microhardness appeared to have higher abrasive wear resistance. The abrasive wear resistance of the WC-based coatings was 4–90 times higher than that of AISI 304 stainless steel under the same testing condition. The abrasive wear mechanism of the WC-based coatings was deduced to be the extrusion and removal of binder phases, as well as the fragmentation and peel-off of hard phases.

Software systems have become larger and more complex than ever. Such characteristics make it very challengeable to prevent software defects. Therefore, automatically predicting the number of defects in software modules is necessary and may help developers efficiently to allocate limited resources. Various approaches have been proposed to identify and fix such defects at minimal cost. However, the performance of these approaches require significant improvement. Therefore, in this paper, we propose a novel approach that leverages deep learning techniques to predict the number of defects in software systems. First, we preprocess a publicly available dataset, including log transformation and data normalization. Second, we perform data modeling to prepare the data input for the deep learning model. Third, we pass the modeled data to a specially designed deep neural network-based model to predict the number of defects. We also evaluate the proposed approach on two well-known datasets. The evaluation results illustrate that the proposed approach is accurate and can improve upon the state-of-the-art approaches. On average, the proposed method significantly reduces the mean square error by more than 14% and increases the squared correlation coefficient by more than 8%.

Spermatogenesis and healthy testicular development are prerequisites for male reproductive function. Androgen receptor (AR), an important receptor in testicular sertoli cells, is involved in androgen specific response and its dysfunction will lead to abnormal sperm development, resulting in male infertility. NONO (non-POU-domain-containing octamer binding protein) can act as a coactivator to enhance the transcription of AR, while AR may be regulated by NONO in testicular sertoli cells. LncRNAs are involved in almost every step of spermatogenesis. However, there are few studies focus on the relationship between lncRNAs and spermatogenesis in goat testis. Therefore, in this research, high throughput sequencing and bioinformatics analysis were performed on testicular tissues of Dazu black goats at different stages of development to obtain the target NONO lncRNA. It's called lncNONO-AS. This study further explored the biological functions of lncRNA through RNA pull down, overexpression, interference, fluorescence quantification, Western blot and other techniques on the basis of in vitro culture of testis sertoli cells, and we got the following results: The gene expression levels of NONO and AR in lncNONO-AS overexpression group were significantly higher than that in the empty vector group (P 0.01). Compared with the untreated negative control group, the expression of NONO decreased from 1.00 to 0.68 (P 0.01), and the expression of AR decreased from 1.01 to 0.34 (P 0.01). The results showed that lncNONO-AS could regulate the expression of AR by mediating the expression of NONO.

Deoxynivalenol (DON), a secondary product of Fusarium metabolism, is common in wheat, corn, barley and other grain crops, posing a variety of adverse effects to environment, food safety, human and animal health. The absorption of DON mainly occurs in the proximal part of the small intestine, which can induce intestinal mucosal epithelial injury, and ultimately affect the growth performance and production performance of animals. This study was conducted to investigate the protective effects of selenium nanoparticles (SeNPs)-enriched Lactobacillus casei ATCC 393 (L. casei ATCC 393) on intestinal barrier function of C57BL/6 mice exposed to DON and its association with endoplasmic reticulum stress (ERS) and gut microbiota. The results showed that DON exposure increased the levels of interleukin-6 (IL-6) and interleukin-8 (IL-8), decreased the levels of interleukin-10 (IL-10) and transforming growth factor beta (TGF-β), caused a redox imbalance and intestinal barrier dysfunction, decreased the mRNA levels of endoplasmic reticulum- resident selenoproteins, activated ERS-protein kinase R-like endoplasmic reticulum kinase (PERK) signaling pathway, altered the composition of the gut microbiota and decreased short-chain fatty acids (SCFAs) content. Dietary supplementation with SeNPs-enriched L. casei ATCC 393 can effectively protect the integrity of intestinal barrier function by reducing inflammatory response, enhancing the antioxidant capacity, up-regulating the mRNA levels of endoplasmic reticulum-resident selenoproteins, inhibiting the activation of PERK signaling pathway, reversing gut microbiota dysbiosis and increasing the content of SCFAs in mice exposed to DON. In conclusion, dietary supplementation with SeNPs-enriched L. casei ATCC 393 effectively alleviated intestinal barrier dysfunction induced by DON in C57BL/6 mice, which may be closely associated with the regulation of ERS and gut microbiota.

Efficient delivery systems for co-delivery of P-glycoprotein (P-gp) inhibitors and chemotherapeutic drugs are essential for inhibiting multi-drug resistance (MDR) breast cancers. Herein, we present a multi-functional carboxymethyl chitosan (CMC) based core-shell nanoplatform to co-deliver MDR1 gene-silenced small interfering RNA (siMDR1) and doxorubicin (DOX) for optimal combinatorial therapy. DOX is linked to CMC through a disulfide bond to model redox-responsive prodrug (CMC-DOX) as the inner core. siMDR1 is encapsulated in oligoethylenimine (OEI), which is electrostatically adsorbed on CMC-DOX as the pH-responsive sheddable shielding shell. AS1411 aptamer and GALA peptide functionalised hyaluronic acid (AHA/GHA) are provided on the surface for tumour-targeting and endo/lysosomal escape. The nanoplatform could stepwise release payloads with acid/redox triggered fashion. AHA effectively improves nanoplatform intracellular uptake and tumour accumulation. GHA facilitates cargos escape from endo/lysosomes to cytoplasm. The multi-functional nanoplatform provides 86.3 ± 2.2% siMDR1 gene silencing and significantly downregulates P-gp expression. Moreover, it ensures 55.7 ± 1.6% MCF-7/ADR cell apoptosis at a low concentration of DOX (30 μg/mL) in vitro and performs synergistic therapeutic effects suppressing tumour growth in vivo. Overall, the multi-functional CMC-based biopolymers can be efficient siRNA/drug co-delivery carriers for cancer chemotherapy.

Strict environmental governance urges firms to implement higher sustainable production requirements and environmental standards for export products, making it challenging for firms to maintain export competitiveness. This study constructs firm-product level markups as the measure of export competitiveness using microdata of millions of observations from Chinese industrial firms. It then empirically investigates the impact of environmental regulations on those firms' export competitiveness. The empirical study finds: 1) environmental regulations have significantly increased the markups of Chinese firms' export products, indicating that firms' export competitiveness is enhanced, verifying the validity of the Porter Hypothesis. 2) Environmental regulations have a greater effect on increasing the markups of non-core products than that of core products. 3) Environmental regulations have significantly increased the markups for private-owned firms, foreign-invested firms, and firms in the eastern region, but not for state-owned and non-eastern firms. 4) Environmental regulation mainly enhances firms' export competitiveness mainly through the TFP channel. Moreover, a series of robustness tests support the empirical results. This research recognizes the positive achievements and benefits of China's environmental governance. It recommends that the Chinese government strengthen the supervision of state-owned enterprises and help enterprises in economically underdeveloped areas overcome the challenges brought by environmental regulation.

In this paper, the high-velocity oxygen-fuel (HVOF) spraying technology was used to prepare the iron-based amorphous coatings onto the substrate of 45 steel. Three parameters of spray distance, oxygen flow and kerosene flow were optimized by the Taguchi method, with the porosity of the coatings as object. The statistical tools including orthogonal experimental design, signal-to-noise ratio and analysis of variance were used to optimize the spray parameters. The results indicated that the kerosene flow showed the highest effect on the porosity of the coatings, while the oxygen flow exhibited the least influence. It was found that the coating with lowest porosity was deposited under the spray distance of 380 mm, the oxygen flow of 1840 scfh, and the kerosene flow of 6.8 gph. The potentiodynamic polarization and electrochemical impendence spectroscopy (EIS) results manifested that the iron-based amorphous coating prepared with proper spray parameters exhibited superior corrosion resistance to the hard chromium coating. Besides, the coating with lower porosity exhibited better corrosion resistance than the coating with higher porosity.

The microcapsules of multilayered shells structure loaded with dicyclopentadiene (DCPD) were prepared via one-part strategy in Pickering emulsions stabilized by hydrolyzed poly(glycidyl methacrylate) (PGMA) nanoparticle. The target microcapsules had polyurethane (PU) inner shell layer, phenol-formaldehyde (PF) outer shell layer, and PGMA outermost layer. Meanwhile, in order to compare with the target microcapsules, the microcapsules of double layered shells (Sample 1) were both acquired. Size distribution, morphology, chemical structure and reaction heat of the capsules were studied by particle size analysis, scanning electron microscopy (SEM), fourier transform infrared spectra (FTIR), nuclear magnetic resonance (NMR), and differential scanning calorimetry (DSC). It was found that the ingredients of PF, PU and PGMA were contained in the target microcapsules of multilayered shells, and the encapsulated core materials still kept high chemical reactivity. The resistant properties against thermal and solvent were evaluated by thermogravimetric analysis (TGA) and the solvent immersion test. When the IPDI content was suitable, the multilayered shells microcapsules (Sample 2, 3) possessed excellent thermal and solvent resistances comparing with Sample 1. In addition, the coatings embedded Sample 3 have displayed good self-healing performance by SEM, electrochemical impedance spectroscopy (EIS), salt immersion test and the tensile analysis of tapered double cantilever beam (TDCB) fracture specimens.

A Fe-based amorphous/nanocrystalline coating was prepared on the AISI 321 steel by the high-velocity oxygen-fuel (HVOF) thermal spraying technology in this paper. Cavitation erosion behavior and mechanism of the coating was studied through the analysis of curves for cavitation erosion resistance versus time and the observation of eroded particles, with the AISI 321 steel as a reference. It was found that the Fe-based coating had better cavitation erosion resistance than the AISI 321 steel, and exhibited obvious periodic failure behavior in the cavitation erosion process. Besides, the crystallization of the amorphous phase under the effect of shock wave was observed. The cavitation erosion mathematic model of the coating was also established. The model indicated that the cavitation erosion resistance of the coating was related to the grain size and the fracture energy per unit area of the coating. Small grain size and high fracture energy per unit area were benefit to improve the cavitation erosion resistance of the Fe-based coating.

Because of the great influence of transition phenomena in aerodynamic property calculations, boundary layer transition has always been a hot research topic in the past few decades. Meanwhile, the prediction methods for boundary layer transition need to be established, researched and enhanced. In order to build a computational fluid dynamics (CFD) compatible transition model, the authors propose a two-equation transport transition model in this paper considering analysis results through linear stability theory (LST). This new transition model consists of one transport equation for laminar fluctuation kinetic energy and another for intermittency factor. Without boundary layer integration and other nonlocal operations, all the variables in this new transition model can be calculated locally so that present model is compatible with CFD parallel computation. Laminar separation bubble induced transition, Tollmien–Schlichting (T–S) instabilities and stationary crossflow instabilities (CF) dominated transition are modeled in the transport equation. The validation tests have been conducted on the classical Schubauer & Klebanoff flat plate, natural laminar airfoil NLF(1)-0416, NLF(2)-0415 infinite swept wing, classical sickle swept wing and 6:1 inclined prolate spheroid using this fully-local transition model. Since all the test cases are in accord with experimental data, the present transition model could be widely applied to aeronautical flows in low-disturbance environment.

In this paper, we have synthesized a series of N-benzoyl-N′-phenyl thiourea derivatives and characterized them by FTIR, elemental analysis, NMR, and X-ray single crystal diffraction. Intermolecular interactions were shown via N H⋯O, N H⋯S, C H⋯O, C H⋯S hydrogen bonds and π⋯π interactions in crystal. Furthermore, antifungal activity of these compounds was determined against Fusarium graminearum, Botryosphaeria ribis, Botryosphaeria berengriana and Cercospora brassicicola P. Hennings. In order to screen anti-cancer drugs, molecular docking was performed by using Hsp90 protein and target ligands (1∼8). Finally, parameters drug-likeness, ADME properties, toxicity effects (mutagenic, tumorigenic, irritant, and reproductive) and drug scores were calculated for evaluating bioavailability of thioureas. The results show that compound 4 has good antifungal activity compared with standard drugs and compound 5 has the potential to become an HSP90 inhibitor. More importantly, all synthesized compounds had good drug-likeness properties.

Suitable semiconductor and its efficient coupling with catalysts is vital to hydrogen evolution reaction (HER). Herein, Ternary heterostructured MoS2/Ag/p-type silicon nanowires (SiNWs) array photocathode are constructed by a simple two-step method, where Ag is self-reduced on SiNWs via Galvanic Displacement method and MoS2 is subsequently loaded by direct thermal decomposition. Ag interfacial layer is introduced between Si and MoS2 to facilitate the charge transfer and suppress the recombination of photo-generated electron-hole pairs. MoS2/Ag/SiNWs exhibits an onset potential of 62 mV and photocurrent density of 50 mA cm−2 at −1.0 VRHE, as well as good stability. Besides, MoS2/Ag/SiNWs is capable of generating 325.9 μL hydrogen per minute. The superior HER catalytic activity of MoS2/Ag/SiNWs is contributed to the improved charge transport at the solid–solid interfaces by virtue of Ag layer, allowing more electrons flow from SiNWs to MoS2 and thus effectively separating the photoelectrons and holes. This work demonstrates the potential of novel heterostructure for robust and efficient photoelectrochemical HER.

This paper proposes a robust H2 optimal control strategy for the depth-plane motion of an autonomous underwater vehicle (AUV) in the presence of output disturbances and time delay. The six degrees of freedom nonlinear kinematic and dynamic equations of motion of the vehicle are firstly described. The depth-plane linearization of the vehicle equations of motion is then derived for efficient controller design from the practical point of view. Using this linearized and reduced-order model, a robust H2 optimal control method is designed. The designed control method takes into account both the output disturbances and time delay and provides suitable control action for desired tracking. The robust stability and robust performance of the proposed control method with respect to the model uncertainties are discussed. Simulation studies demonstrate that the proposed robust H2 optimal control strategy has remarkable performance and provides higher tracking accuracy, better output disturbances rejection ability, stronger robustness against model uncertainties, and smaller fin angle input than the existing pitch-and-depth loop PD depth controller.