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This paper addresses the trajectory tracking problem for a class of uncertain manipulator systems under the effect of external disturbances. The main challenges lie in the input constraints and the lack of measurements of joint velocities. An extend‐state‐observer is utilized to estimate the velocity signals; then, a neural‐network‐based adaptive controller is proposed to solve the problem, where a term based on the nominal model is included to enhance the tracking ability, and the effect of uncertainties and disturbances are compensated by a neural‐network term. Compared with the existing methods, the main distinctive features of the presented approach are: (i) The control law is guaranteed to be bounded by design, instead of directly bounded by a saturation function. (ii) The trade‐off between the performance and robustness of the presented controller can be easily tuned by a parameter that depends on the size of model uncertainties and external disturbances. By virtue of the Lyapunov theorem, the convergence properties of the proposed controller are rigorously proved. The performance of the controller is validated via both simulations and experiments conducted on a two‐degree‐of‐freedom robot manipulator. [ABSTRACT FROM AUTHOR]

Background: Laminin subunit gamma-1 (LAMC1) is a major extracellular matrix molecule involved in the tumor microenvironment. Knowledge of the biological features and clinical relevance of LAMC1 in cancers remains limited. Methods: We conducted comprehensive bioinformatics analysis of LAMC1 gene expression and clinical relevance in pan-cancer datasets of public databases and validated LAMC1 expression in glioma tissues and cell lines. The association and regulatory mechanism between hypoxia inducible factor-1α (HIF-1α) and LAMC1 expression were explored. Results: LAMC1 expression in most cancers in The Cancer Genome Atlas (TCGA) including glioma was significantly higher than that in normal tissues, which had a poor prognosis and were related to various clinicopathological features. Data from the Chinese Glioma Genome Atlas also showed high expression of LAMC1 in glioma associated with poor prognoses. In clinical glioma tissues, LAMC1 protein was highly expressed and correlated to poor overall survival. LAMC1 knockdown in Hs683 glioma cells attenuated cell proliferation, migration, and invasion, while overexpression of LAMC1 in U251 cells leads to the opposite trend. Most TCGA solid cancers including glioma showed enhancement of HIF-1α expression. High HIF-1α expression leads to adverse prognosis in gliomas, besides, HIF-1α expression was positively related to LAMC1. Mechanistically, HIF-1α directly upregulated LAMC1 promotor activity. Hypoxia (2% O2)-treated Hs683 and U251 cells exhibited upregulated HIF-1α and LAMC1 expression, which was significantly attenuated by HIF-1α inhibitor YC-1 and accompanied by attenuated cell proliferation and invasion. Conclusions: High expression of LAMC1 in some solid tumors including gliomas suggests a poor prognosis. The hypoxic microenvironment in gliomas activates the HIF-1α/LAMC1 signaling, thereby promoting tumor progression. Targeted intervention on the HIF-1α/LAMC1 signaling attenuates cell growth and invasion, suggesting a new strategy for glioma treatment. [ABSTRACT FROM AUTHOR]

The treatment of neurological disease, such as epilepsy is rather complicated. Emerging therapies such as surgery, gene therapy, stem cell transplantation, and neurostimulation have been developed to replace traditional drug therapy. However, great challenges such as the difficult localization of epileptic foci (EF), incomplete excision of lesioned nerves, high drug resistance, and severe side effects limit their clinical applications. As an alternative, bioinorganic materials have been emerged and show great potentials for epilepsy theranostics. Their unique physical properties, including fluorescence, magnetic resonance effect, and surface‐enhanced Raman scattering effect (SERS), give them the ability to image the localization of EF. In addition, the fluorescence and conductivity of bioinorganic materials could be further used for studying pathogenesis. Moreover, bioinorganic materials could serve as intelligent systems to deliver drugs and cooperative therapy for epilepsy. Herein, this review highlights the design and application of bioinorganic materials in the imaging, diagnosis, and therapy of epilepsy. Furthermore, light is shown on the potential bottlenecks and future perspectives of bioinorganic materials in epilepsy theranostics. [ABSTRACT FROM AUTHOR]

AbstractIn our research described here, a strong acid oxidizing agent was selected to modify the surface of carbon black (CB) to obtain oxidized carbon black (OCB) particles. These OCB particles were then subjected to an ionic bonding reaction with alkaline amine groups present on the surface of octadecylamine polyoxyethylene ether (AC1830) in the form of a paste, resulting in the production of polyether amine-modified oxidized carbon black particles (A-CB). FTIR confirmed the successful production of the A-CB particles. The PVA composite films were prepared using the casting method with varying amounts of A-CB as filler and PVA as the matrix. The films were then analyzed using tensile, scanning electron microscopy, dynamic thermo-mechanical analysis, DSC, and water absorption testing. The results showed that the tensile strength was highest at 3% A-CB, reaching 154.85 MPa. A-CB was well dispersed in PVA at low contents (1% and 3%). The loss modulus, energy storage modulus, crystallinity, and crystallization rate of the A-CB/PVA films improved compared to PVA films. Additionally, the issue of excessive water absorption in A-CB/PVA has been improved. [ABSTRACT FROM AUTHOR]

The aims of this study are to screen novel differentially expressed genes (DEGs) for intracerebral hemorrhage (ICH) and reveal the role of Lipocalin-2 (LCN2) in ICH.Methods: We constructed the ICH model by injection of autologous whole blood into the right basal ganglia in rats. RNA-sequencing and bioinformatics analyses were performed to identify the DEGs between ICH and sham rats, and some important ones were confirmed using quantitative real-time PCR (qRT-PCR). LCN shRNA was used to knockdown of LCN2 in ICH rats. Pathological examination was carried out using 2,3,5-triphenyltetrazolium chloride (TTC) staining and Hematoxylin-eosin (HE) staining. Immunohistochemistry detected Caspase-3, and co-staining of Terminal dUTP nick end labeling (TUNEL) and NEUN staining were performed for neuron apoptosis assessment. Western blot analysis was performed to quantify pyroptosis-related proteins. Enzyme-linked immunosorbent assay (ELISA) was used to measure inflammatory cytokine levels.Results: ICH rats exhibited significant hematomas, higher brain water content, obvious interstitial edema, and inflammatory infiltration, as well as more apoptotic cells in brain tissues. RNA-seq analysis identified 103 upregulated and 81 downregulated DEGs. The expression of LCN2, HSPB1, CXCL10, and MEF2B were upregulated in ICH rats. ICH triggered the release of interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), and IL-18, and promoted the expression of pyroptosis-related proteins Caspase-1, GSDMD, NLRP3, and ASC. LCN2 knockdown attenuated the pathological characteristics of ICH, and also reduced pyroptosis in brain tissues.Conclusion: Inhibition of LCN2 attenuates brain injury after ICH via suppressing pyroptosis, which provide guidance for ICH management. [ABSTRACT FROM AUTHOR]

AbstractIn this work, a mesoporous silica (SBA-15) was synthesized using a hydrothermal method and the surface of the SBA-15 was further modified by utilizing the organosilane compound γ- aminopropyltriethoxysilane(APTES); FT-IR testing confirmed the successful grafting of these organic groups onto the surface of the SBA-15, the result being the AP-S. Composite films were subsequently prepared through a casting method, with SBA-15 and AP-S serving as the inorganic filler particles, and PVA acting as the matrix material. These films were characterized by tensile texts, dynamic mechanical analysis, scanning electron microscopy, and dielectric measurements. The results showed that the tensile modulus, loss modulus and dielectric properties of the modified AP-S/PVA composite films were improved compared with those of SBA-15/PVA, with the tensile strength being the largest at 145.25 MPa when the AP-S content was 2%. This result combined with the SEM analysis, shows that the incorporation of SBA-15 modified by APTES into PVA films can effectively improve the dispersion of SBA-15 in the PVA films, which can also explain the performance enhancement. [ABSTRACT FROM AUTHOR]

Echinococcosis is a highly prevalent global zoonosis, and vaccines are required. The commercial vaccine based on a protein-based subunit (EG95), however, is limited by its insufficient cellular immunity, a short protection period, and limited prevention against novel mutant strains. Herein, we applied bioinformatics to develop a DNA vaccine (pEG95-IL2) expressing both multi-epitope-based antigens (EG95-PT1/2/3) and an IL-2 adjuvant to regulate T cell differentiation and memory cell response. EG95-PT1/2/3 was screened with hierarchical structure prediction from the epitope conformation of B cells with high confidence across various species to guarantee immunogenicity. Importantly, cationic arginine-rich lipid nanoparticles (RNP) were utilized as a delivery vehicle to form lipoplexes that had a transfection efficiency of nearly two orders of magnitude greater than that of commercial reagents (Lipofectamine 2000 and polyethyleneimine) with both immune and nonimmune cells (DC2.4 and L929 cells, respectively). RNP/pEG95-IL2 lipoplexes displayed a robust and long-term antigen expression, as well as adjuvant effects during the immunization. Consequently, intramuscular injection of RNP/pEG95-IL2 elicited similar humoral immune responses and significantly greater cellular responses in mice when compared with those of the commercial vaccine. In addition, the inoculation protocol of RNP/pEG95-IL2 with sequential booster further strengthens cellular immunity in comparison with the homologous booster. Those findings provide a promising strategy for improving plasmid vaccine efficacy. [Display omitted] • Multi-epitope-based DNA vaccine (RNP/pEG95-IL2) was developed by bioinformatics technology. • RNP/pEG95-IL2 elicited stronger cellular immune responses compared to the commercial vaccine. • The SB strategy of DNA vaccine produced greater immune responses than HB. • RNP benefited high and long-lasting expression of DNA antigens. • RNP accelerated BMDCs maturation and cytokine production as an immune adjuvant. [ABSTRACT FROM AUTHOR]

To address the challenges associated with the weak affinity and difficult separation of biochar, we developed chitosan–biochar hydrogel beads (CBHBs) as an efficient solution for removing reactive brilliant blue (RBB KN-R) from wastewater. The adsorption behavior and mechanism of RBB KN-R onto CBHBs were extensively studied. Notably, the adsorption capacity of RBB KN-R showed pH-dependence, and the highest adsorption capacity was observed at pH 2. The adsorption process was well fitted with the pseudo-second-order kinetic model and the intraparticle diffusion model. Film diffusion and intraparticle diffusion were both responsible for the adsorption of RBB KN-R onto CBHBs. At 298.15 K, the maximum adsorption capacity qm was determined to be 140.74 mg/g, with higher temperatures favoring the adsorption process. A complex mechanism involving π–π interactions, electrostatic attraction, hydrophobic interaction, and hydrogen bonding was found to contribute to the overall adsorption process. The experimental data discovered the coexisting substances and elevated ionic strength hindered the adsorption capacity. Significantly, after three cycles of adsorption–desorption, the CBHBs maintained an adsorption capacity above 95% for RBB KN-R. These promising results imply that CBHBs are a durable and cost-effective adsorbent for efficient removal of dyes from wastewater. [ABSTRACT FROM AUTHOR]

In this study, a new pretreatment method was proposed for efficient nondestructive substrate pretreatment of carbon fiber-reinforced plastic (CFRP) skin stealth coatings for 4th and 5th generation fighter jets, which can effectively replace hand sanding and meet the requirements of high efficiency and damage prevention of the substrate. Erosion experiments were carried out on a commercial sandblasting cabinet by the Taguchi method for CFRP skin pretreatment. The mechanisms of hand sanding and plastic abrasive jet machining (PAJM) were introduced in detail. The advantages of PAJM over hand sanding for CFRP skin pretreatment were investigated in terms of surface morphology, wettability, and adhesion, in order to achieve the objective of enhancing coating adhesion and prolonging the service life of the substrate. These results show that the damage of PAJM-eroded surfaces is lower than that of hand-sanded surfaces, and safe process parameters for no fiber damage are provided. The critical pressure of carbon fiber damage was likely to be 0.4 MPa or lower, and the adhesion of primer could reach 3.6 MPa. This study provides significant guidance for the pretreatment of new-generation aircraft CFRP skin. The erosion mechanism of plastic abrasive is semi-ductile erosion. Compared with manual sanding, PAJM is more suitable for carbon fiber-reinforced plastic (CFRP) substrates pretreatment. The proper PAJM process can realize the non-destructive CFRP substrate. Obtained the best pretreatment process [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the safety and benefits of the biplanar position technique on operative time, radiation exposure, and screw placement accuracy. Methods: In this study, we retrospectively evaluated the records of 64 patients with pelvic fractures (Tile B and C) between October 2020 and September 2021. According to the surgical methods selected by the patients, the patients were divided into a biplanar positioning technique group (biplanar group), a Ti-robot navigation group (Ti-robot group), and a traditional fluoroscopy-guided technique group (traditional group). Length of operation, blood loss, intra-operative radiation exposure fracture reduction, and the quality of screw positioning were compared among the three groups. Results: One hundred three screws were implanted in 64 patients (biplanar group 22, Ti-robot group 21, traditional group 21). The average operation time was significantly less in the biplanar group (26.32 ± 6.32 min) than in the traditional group (79.24 ± 11.31 min), but significantly more than in the Ti-robot group (15.81 ± 3.9 min). The radiation exposure was similar in the biplanar group (740.53 ± 185.91 cGy/cm2) and Ti-robot group (678.44 ± 127.16 cGy/cm2), both of which were significantly more than in the traditional group (2034.58 ± 494.54 cGy/cm2). The intra-operative blooding loss was similar in the biplanar group (12.76 ± 3.77 mL) and the Ti-robot group (11.92 ± 4.67 mL), both of which were significantly less than in the traditional group (29.7 ± 8.01 mL). The Screw perforation was slightly lower in the biplanar group (94.1%) than in the Ti-robot group (97.2%) but was significantly higher than in the traditional group (75.7%). Conclusions: The biplanar positioning technique is as accurate and safe as computer-navigated systems for percutaneous iliosacral screw insertion, associated with shorter surgical time, lower intra-operative radiation exposure, and more accuracy compared to traditional fluoroscopy. [ABSTRACT FROM AUTHOR]

Multi‐view image fusion can be used to extract features from redundant and complementary multisource images. And the technique of obtaining high quality fusion images has become one of the research hotspots for image processing. In order to realize defect detection and intelligent grinding smoothly, multi‐view fusion technology was applied in the field of overexposure and underexposure industrial welds, achieving high quality image enhancement. When preparing the data set of multi‐view images, a hybrid registration algorithm with high matching ability is proposed. The data set of overexposure and underexposure weld images was obtained successfully by using the registration algorithm. In order to improve the fusion ability of overexposure and underexposure industrial welds, we propose a novel multi‐view image fusion algorithm based on deep learning. The multi‐view fusion algorithm uses an autoencoder network structure, and its innovation lies in a parallel branch network with lightweight structure and strong generalization ability. The experimental results demonstrate that compared with other classical multi‐view algorithms, our proposed algorithm gets the best parameters on the industrial weld data set in peak signal to noise ratio (PSNR) and root mean square error (RMSE), reaching 59.12 and 0.084, respectively. And the ablation and performance comparison experiments verify that the proposed parallel branch network has better generalization ability and fusion accuracy than other classical multi branch networks. [ABSTRACT FROM AUTHOR]

Drought is an extremely dangerous natural hazard that causes water crises, crop yield reduction, and ecosystem fires. Researchers have developed many drought indices based on ground-based climate data and various remote sensing data. Ground-based drought indices are more accurate but limited in coverage; while the remote sensing drought indices cover larger areas but have poor accuracy. Applying data-driven models to fuse multi-source remote sensing data for reproducing composite drought index may help fill this gap and better monitor drought in terms of spatial resolution. Machine learning methods can effectively analyze the hierarchical and non-linear relationships between the independent and dependent variables, resulting in better performance compared with traditional linear regression models. In this study, seven drought impact factors from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensor, Global Precipitation Measurement Mission (GPM), and Global Land Data Assimilation System (GLDAS) were used to reproduce the standard precipitation evapotranspiration index (SPEI) for Shandong province, China, from 2002 to 2020. Three machine learning methods, namely bias-corrected random forest (BRF), extreme gradient boosting (XGBoost), and support vector machines (SVM) were applied as regression models. Then, the best model was used to construct the spatial distribution of SPEI. The results show that the BRF outperforms XGBoost and SVM in SPEI estimation. The BRF model can effectively monitor drought conditions in areas without ground observation data. The BRF model provides comprehensive drought information by producing a spatial distribution of SPEI, which provides reliability for the BRF model to be applied in drought monitoring. [ABSTRACT FROM AUTHOR]

Removing localized damage coatings on new-generation fighters' carbon fiber reinforced plastic (CFRP) skin surfaces has become a research hotspot. A practical method for removing the CFRP skin coating without damaging the substrate was proposed in this study. Modeling was used to examine the particle velocity and contact force of a single abrasive and the erosion depth, width, and material removal rate of the coating. The eroded surface morphology, roughness and erosion depth of different processes were obtained by the Taguchi method. The results show that plastic abrasive jet machining (PAJM) can remove coatings layer by layer without damaging the substrate. A jet pressure of 0.35 MPa is recommended as a critical jet pressure to avoid damaging the fibers. This procedure offers more advantages than traditional removal methods (chemical stripping or manual sanding). A theoretical reference for coating removal on CFRP skin surfaces is provided in this paper. [ABSTRACT FROM AUTHOR]

Substrate damage brings great challenges to the efficient and nondestructive removal of aircraft skin coatings. Variable load erosion tests of unidirectional carbon fiber reinforced plastic along different fiber orientations were carried out. The effects of different fiber orientations on the erosion mechanism of CFRP are discussed separately. The matrix resin is squeezed and accumulated as platelets due to the erosion of the particles, and these platelets are removed due to repeated impacts of subsequent abrasives. The epoxy resin on the top layer of the laminate is penetrated by the particles with increased energy loss, and the fiber breakage is attributed to the direct impact of the particles on the carbon fiber. Fiber fractures are divided into micro-brittle fractures and macro-brittle fractures. Cracks are initiated by the concentrated stress of particle extrusion and propagate between the graphite crystallites, resulting in irregular micro-brittle fracture and fiber failure. Under the condition of macro-brittle fracture, the fiber will be debonded, flexural deformed, and even lost under the concentrated stress of particle extrusion. The purpose of this study is to provide a theoretical reference on the mechanism by which nondestructive and efficient removal of stealth coatings can be achieved on aircraft skins. [ABSTRACT FROM AUTHOR]

A low-temperature Liquid Nitrogen Ring-on-Ring end-face contact friction Test Platform (LNR-RTP) was set up and applied to test the tribological behavior on metal/graphite ring-on-ring end-face contact pair. The friction coefficients and wear rates were obtained, and the wear mechanism was analyzed. The results show the friction coefficient increases with the rotational speed under the low temperature conditions and the low load from 50 to 100 N. With the load increasing, the friction coefficient is stable with the change of rotational speed, which is 0.05. The wear cross-section shows a taper shape from the inner to outer diameter, which implies a transition of the wear mechanism from the adhere wear to three-body wear under the low temperature conditions. [ABSTRACT FROM AUTHOR]

• Neutron irradiation effects are studied in PM-HIP compared to forged SA508 low-alloy steel, following ∼0.5–1.0 dpa at ∼270 °C and ∼370 °C. • PM-HIP more susceptible than forged to Mn-Ni-Si-P nanoprecipitation and dislocation loop nucleation due to higher Mn, Ni concentration. • Greater irradiation hardening and embrittlement in PM-HIP than forged, but PM-HIP retains higher ductility through maximum load-bearing capacity. • Results can support nuclear code qualification of PM-HIP products. Powder metallurgy with hot isostatic pressing (PM-HIP) is an advanced manufacturing process that is envisioned to replace forging for heavy nuclear components, including the reactor pressure vessel (RPV). But PM-HIP products must at least demonstrate comparable irradiation tolerance than forgings in order to be qualified for nuclear applications. The objective of this study is to directly compare PM-HIP to forged SA508 Grade 3 Class 1 low-alloy RPV steel at two neutron irradiation conditions: ∼0.5–1.0 displacements per atom (dpa) at ∼270 °C and ∼370 °C. PM-HIP SA508 experiences greater irradiation hardening and embrittlement (total elongation) than forged SA508. However, uniform elongation and approximate toughness are comparable across all irradiated materials, suggesting irradiated PM-HIP SA508 exhibits superior ductility at maximum load-bearing capacity. The irradiation hardening mechanism is linked to composition rather than fabrication method. Since PM-HIP SA508 has higher Mn and Ni concentration, it is more susceptible to irradiation-induced nucleation of Mn-Ni-Si-P (MNSP) nanoprecipitates and dislocation loops, which both contribute to hardening. Conversely, the forged material nucleates fewer MNSPs, causing dislocation loops to control irradiation hardening. These results show promise for the irradiation performance of PM-HIP SA508 and can motivate future nuclear code qualification of PM-HIP fabrication for RPVs. [Display omitted] [ABSTRACT FROM AUTHOR]

Software refactoring is one of the most significant practices in software maintenance as the quality of software design tends to deteriorate during software evolution. But, refactoring software is a very challenging task as it requires a holistic view of the entire software system. To this end, recent studies introduced search-based algorithms to facilitate software refactoring. However, they still have the following major limitations: 1) the searched solutions may violate the design principles as their fitness functions do not directly reflect the degree of software’s compliance with design principles; 2) most approaches start the searching process from a completely random initial population, which may lead to unoptimal solutions. In this article, we aim to develop effective search-based refactoring approach to recommend better refactoring activities for developers which can improve the degree of software’s compliance with design principles as well as the software design quality. We propose DEPICTER, a design-principle guided and heuristic-rule constrained software refactoring recommendation approach. In particular, DEPICTER uses non-dominated sorting genetic algorithm (NSGA)-II genetic algorithm and employs design-principle metrics as fitness functions. Besides, DEPICTER leverages heuristic rules to improve the quality of initial population for subsequent generic evolution. Our evaluations, based on four widely used systems, show that DEPICTER is effective for guiding the development of better refactoring models in practice. [ABSTRACT FROM AUTHOR]

InGaAs/graphene Schottky photodiode has a low Schottky barrier height (SBH) which induces high dark current density. In this paper, an Al2O3 thin film is inserted between the layer of InGaAs and graphene to suppress the dark current density for nearly two orders of magnitude. As a result, it is a distinct enhancement on the performance that the graphene/Al2O3/InGaAs near-infrared photodetector (NIR PD) under −0.4 V has a better responsivity of 523.77 mA W−1 and a better detectivity of 4.42 × 1010 cm Hz1/2/W to 1064 nm incident light than the graphene/InGaAs NIR PD. Moreover, graphene/Al2O3/InGaAs NIR PD also has a great response to 1550 nm incident light and the degradation on the device was observed. With the calculation, an increase of 0.122 eV on the Schottky barrier height (SBH) of graphene/Al2O3/InGaAs was founded. The result is expected to promote the application of the graphene NIR PD to the novel sensors. [ABSTRACT FROM AUTHOR]

Recently, deep learning methods have attracted much attention in the field of polarimetric synthetic aperture radar (PolSAR) data interpretation and understanding. However, for supervised methods, it requires large-scale labeled data to achieve better performance, and getting enough labeled data is a time-consuming and laborious task. Aiming to obtain a good classification result with limited labeled data, we focus on learning discriminative high-level features between multiple representations, which we call mutual information. As PolSAR data have multi-modal representations, there should have strong similarity between multi-modal features of the same pixel. In addition, each pixel has its own unique geocoding and scattering information. Hence, every pixel has great difference from other pixels in a specific representation space. Based on the above observations, this article proposes a mutual information-based self-supervised learning (MI-SSL) model to learn an implicit representation from unlabeled data. In this article, the self-supervised learning idea is first applied to PolSAR data processing. Furthermore, a reasonable pretext task, which is suitable for PolSAR data, is designed to extract mutual information for classification tasks. Compared with the state-of-the-art classification methods, experimental results on four PolSAR data sets demonstrate that our MI-SSL model produces impressive overall accuracy with fewer labeled data. [ABSTRACT FROM AUTHOR]

It is a research hotspot of electric propulsion system that a high energy density permanent magnet machine is used as its main power. In general, the power system of electric propulsion consists of batteries, inverters and high energy density permanent magnet machines and loads. Based on harmonic effect of PWM sine alternating current generated by inverter, iron loss model of high energy density permanent magnet machine is established under inverter power harmonic, and iron loss calculation flow chart of high energy density permanent magnet machine for electric propulsion system is shown. The influences of different stator outer diameter and rotor inner diameter on iron loss are analyzed by using the finite element method. Through the above analysis, a 30 kW high energy density permanent magnet machine was designed. Then the noload test and iron loss separation test were carried out, verifying that the machine has very low core loss. [ABSTRACT FROM AUTHOR]

The preparation methods of T300 carbon cloth- and aramid cloth-reinforced epoxy resin and cyanate ester were proposed, and four kinds of composite samples were obtained. The friction coefficient and wear rate under different test times and loads were obtained using a reciprocating pin-disk tribology tester. The tribology pairs included pins or sliding blocks made from different metals (45 steel and brass) and the disk samples of the composites. The test results showed that the friction coefficients of the T300 carbon cloth- (T300/4211 and T300/BS-4) and aramid cloth- (aramid/4211 and aramid/BS-4) reinforced epoxy resin or cyanate ester changed from 0.09 to 0.3 and were low under dry friction conditions. Under 75 N, aramid/BS-4 coupled with 45 steel pins was the lowest friction coefficient, which was 0.09. In particular, the friction coefficient and wear rate of the composite-reinforced cyanate ester were the lowest, which meant that this composite may be more suitable for use under lightly loaded and reciprocating running conditions in space engineering. By comparing the surface morphologies of composites before and after the test, the wear mechanism of the composites was discussed and the lower friction coefficient and wear rate may originate from the abrasive wear effects occurring between the tribology pairs. The research results have important engineering significance for guiding the use of composites in the deployable mechanisms used in space engineering. [ABSTRACT FROM AUTHOR]

• A gradient-nanostructure of AISI 1045 steel was formed by ultrasonic surface rolling processing (USRP). • USRP not only improves the fatigue performance but also the consistency. • Residual stress in the entire thickness direction was determined by contour methods. • The mechanism of various factors caused by USRP affecting fatigue was revealed. In the study, AISI 1045 steel were treated by ultrasonic surface rolling processing (USRP) with different parameters in terms of coverage rate. The gradient structures characterized with refined polished surface, the sub-surface nano-lamellar microstructure with a maximum compressive residual stress of 453.4 MPa was obtained, which shall be responsible to the superior fatigue properties to the pristine. Furthermore, the comparative investigation of fatigue behavior demonstrates that the surface roughness has the pronounce effects on the resistance to crack initiation, though the excessive USRP with the surface roughing may result in the premature crack growth; in contrast to the gradient microstructure, the compressive residual stress may delay effectively the incubation and increase the growth resistance of the physically short crack. Besides, the benefit of gradient microstructure is relatively limited in the resistance of fatigue short crack propagation. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: To search for potent insecticides targeting at ryanodine receptors (RyRs), a series of novel anthranilic diamides analogs containing 4‐chlorine N‐pyridylpyrazole were designed and synthesized. Their insecticidal activities were evaluated and the preliminary structure‐activity relationships (SARs) were discussed. The insecticidal results showed that some of the compounds (8a—8h, 8m, 8n) exhibited good larvicidal activities against oriental armyworm at 2.5 mg·L–1, and compound 8m possessed 60% insecticidal activity at 0.5 mg·L–1. For diamondback moth, 8m exhibited better activity than Chlorantraniliprole at a hundred fold preference. The calcium imaging technique experiment results suggested that compound 8m could increase the intracellular [Ca2+]i. With the neurons preincubated experiment, the results confirmed that the target of this series of compounds could be RyRs in the central larvae neurons of oriental armyworm. The results indicated that compound 8m could respond as a potential modulator of the insect ryanodine receptor. [ABSTRACT FROM AUTHOR]

Whether or not biogeographic rules dealing with spatial patterns of animal body sizes are valid for ectotherms is controversial. As the ectotherms grow all their lives, we explored the role of age and annual growth rate in body size variation in Phrynocephalus przewalskii in northern China. Morphological data were collected from 11 populations across a broad geographic gradient. Correlations between age, sex, climatic factors, and body size were analyzed using generalized linear model (GLM) and generalized linear mixed model (GLMM). GLM analysis indicated that the general body size of both sexes and the appendage size of females increased significantly with increasing temperature; however, the coefficient of determination was very small. GLMM analysis indicated that body size only correlated with age, whereas appendage size was affected by age, temperature, rainfall, and sunshine. Annual growth rates were positively correlated with temperature. We concluded that body size variation was mainly caused by age structure and plasticity of the growth rate in P. przewalskii and did not follow Bergmann's rule; however, females followed Allen's rule. Future studies to investigate the effect of energy restriction are needed to further understand the relationship between growth rate and body size. We also suggest that further studies on thermal advantage and sexual selection may be helpful to understand appendage size variation in P. przewalskii. [ABSTRACT FROM AUTHOR]

We examined the dynamics of dissolved inorganic carbon (DIC) and pH in the Pearl River Estuary (PRE) and the adjacent northern South China Sea (NSCS) shelf in summer, aiming for a better understanding of the interaction between eutrophication, hypoxia, and ocean acidification. Using a semi‐analytical diagnostic approach based on validated multiple end‐member water mass mixing models, we showed a −191 ± 54 μmol kg−1 deficit in DIC concentrations in an extensive surface plume bulge, corresponding to a significant pH increase of ∼ 0.57 ± 0.19 units relative to conservative mixing. In contrast, DIC additions in the bottom hypoxic zone reached ∼ 139 ± 21 μmol kg−1, accompanied by a decrease in pH of −0.30 ± 0.04 units. In combination with stable carbon isotopic compositions, we found biological production and CO2 outgassing to be responsible for DIC deficits in surface waters, while degradation of organic matter (OM) accounted for DIC additions in bottom waters. The PRE‐NSCS plume system as a whole served as a net source of atmospheric CO2 from the perspective of Lagrangian observations, because strong CO2 outgassing in the inner estuary overwhelmed the CO2 uptake in the plume despite strong phytoplankton blooms. Using a two‐layer box model, we further estimated that at least ∼ 45 ± 13% of eutrophication‐driven OM production in the surface plume accounted for 67 ± 18% of the DIC addition and oxygen consumption in bottom waters. Eutrophication also buffered ocean acidification in surface waters while hypoxia enhanced it in bottom waters, but their effects on acid‐base buffering capacity were secondary to the amplification of coastal ocean acidification caused by freshwater inputs. [ABSTRACT FROM AUTHOR]

Large-area ZnO nanowire field emitter arrays have important applications in flat-panel displays, light sources, photodetectors and X-ray sources, where it is crucial to realize a high field emission current and current density over a large-area. In this paper, large-area ZnO nanowire arrays with various array spacings were prepared by the thermal oxidation technique from patterned Zn film arrays, and their field emission properties were studied. The results show that the Zn array density is related to the nanowire length and population density. A mechanism is proposed wherein the stress-induced process and mass transport process both play key roles in the growth. Herein, ZnO nanowire arrays in a 4.7 × 4.7 cm2 area exhibited a sufficient quantity of emission sites and diminished field screening effect and a high current of 12.9 mA with a current density of 0.58 mA/cm2. This work provides useful guidance for optimizing ZnO nanowires and enhancing field emission current performance for large-area ZnO nanowire field emission devices. • ZnO nanowire field emitter arrays with various spacing were used to diminish field screening effects. • High current and stable emission was achieved from large-area ZnO nanowire field emitter arrays. • A facile and useful approach is proposed to tune the nanowire length and population density. • A growth mechanism based on stress-induced process and mass transport process was proposed. [ABSTRACT FROM AUTHOR]

Highlights • A numerical study of the influence of pulsing parameters in GMAW-P is presented. • Waveforms using different pulsing parameters but an identical average current are considered and compared. • Pulse with higher peak current but shorter duration leads to significantly higher detaching speed. • Average temperature of the transferring drop increases slightly with the peak current. Abstract The effect of pulsing parameters on the metal and heat transfer behaviors in pulsed gas metal arc welding is investigated by a numerical model based on the solution of the magnetohydrodynamic equations within the framework of phase field method. Five sets of current waveforms using different peak current and duration (i.e. 300 A-2.30 ms, 350 A-1.80 ms, 400 A-1.45 ms, 450 A-1.20 ms and 500 A-1.00 ms) but maintaining an identical average current (i.e. 170 A) are considered and compared. The pulses using higher current but shorter duration result in more elongated shape of the pendent drop, earlier detachment, and significantly higher velocity of the detached drop. Unlike the drop velocity, higher peak current merely leads to a slight increase in the average temperature of the detached drop. The reason for this slight increase is that only the joule heating increases with the peak current, while the sheath heating and arc heating is governed by the average current and keeps almost constant using different pulsing parameters. The simulation results are compared with the high speed photos and exhibit good agreements. [ABSTRACT FROM AUTHOR]

Highlights • pH showed complicated effects on protein uptake to two PEI-grafted Sepharose. • Both capacity and uptake rate on high-charge resin showed up-down-up trends with pH. • Charge-reduced resin gave both maximal capacity (257 mg/mL) and uptake rate at pH 5.5. • The two resins showed high dynamic capacities at different pH or salt concentrations. • Dynamic capacities over 120 mg/mL were observed on charge-reduced resin at pH 5.5–8. Abstract Previously, we have studied protein adsorption behaviors on a series of poly(ethylenimine) (PEI)-grafted Sepharose FF, and a critical ionic capacity of PEI-grafted resins was observed, above which both protein adsorption capacity (q) and effective pore diffusivity (D e) increased drastically. Moreover, reducing the charge density of the PEI-grafted resins from an ionic capacity of 740 mmol/L (FF-PEI-L740) to 440 mmol/L (FF-PEI-R440) by neutralization of the amino groups of PEI chains with sodium acetate brought out a three-fold increase of D e value at pH 8. In this work, FF-PEI-L740 and FF-PEI-R440 were selected to investigate the complicated effects of pH on protein adsorption behavior using bovine serum albumin (BSA) as the model protein. It was found that, for FF-PEI-L740, both the q and D e values decreased significantly when pH decreased from 9 to 5.5, and then increased dramatically at pH 5, and finally decreased remarkably at pH 4.5. The results were considered due to the following causes: The decrease of pH from 9 to 5.5 led to a greatly increased electrostatic repulsion between the PEI chains due to the increased dissociation degree of PEI, which caused the increase in steric hindrance effects and decrease in the bound protein transport by chain delivery. At pH 5, which was near the p I of BSA (∼4.9), the presence of few protein charges greatly decreased the electrostatic hindrance effect on protein transport and the high charge density of FF-PEI-L740 provided extensively accessible binding sites and facilitated the happening of chain delivery as well. At pH 4.5, the net charge of BSA shifted to positive, likely charged with PEI, so the overall electrostatic repulsion greatly hindered protein uptake. For FF-PEI-R440, whose charge density was much lower than FF-PEI-L740, its q and D e values even increased mildly when pH decreased from 8 to 5.5, because its slightly-increased charge density did not cause much increased electrostatic and steric hindrance effects but provided more binding sites for protein adsorption. At pH 5, the few charges of BSA and the low charge density of FF-PEI-R440 could not afford enough electrostatic interaction for protein binding, resulting in significantly decreased q and D e values. Besides, column breakthrough experiments revealed that FF-PEI-R440 kept high dynamic binding capacity (DBC) (>120 mg/mL) at pH 5.5–8, while FF-PEI-L740 offered high DBC (>80 mg/mL) at pH 5, 7 and 8 with a higher salt concentration (100 mmol/L NaCl). These findings demonstrated the excellence of FF-PEI-L740 and FF-PEI-R440 in different conditions, and would help in the design and selection of suitable resins for high-performance protein chromatography. [ABSTRACT FROM AUTHOR]

Highlights • Optimizations of 3 compound power cycles have been carried out thermodynamically. • Five maps are obtained for selecting optimum geothermal power generation cycles. • Different ORC working fluids are investigated in generating the maps. • Techno-economic performance of each power cycle has been analyzed in detail. Abstract Both thermodynamic performance and techno-economic analysis of compound power cycles for enhanced geothermal systems have been investigated in this study. Thermodynamic analysis were carried out for four power generation systems: single-flash (SF) system, double-flash (DF) system, flash-ORC (FORC) system; and double-flash-ORC (DFORC) system. By choosing the maximum net power output as an objective function, optimization is done based on comparisons among the four systems with a goal of increasing the net power output by 20% under the condition that the SF is replaced by one of the compound systems (DF, FORC, and DFORC). As an original contribution, five maps useful for real applications have been generated for selecting optimum geothermal power cycles under different geofluid's conditions, with consideration of five ORC working fluids (R123, R152a, isobutane, n -pentane and R245fa). The boundaries that determine whether the compound systems have advantages over the SF system are functions of the geofluid temperature, geofluid dryness, and the type of the working fluid used by the ORC. In the techno-economic study, Levelized Electricity Cost (LEC) and Payback Period (PBP) analyses were carried out. The results from the LEC and PBP studies show good agreement. For the three scenarios analyzed, each of the compound power systems has a better engineering economic performance than the SF system. For the "common" heat source condition investigated, comparison among the three compound systems shows that the DF system has a lowest levelized electricity cost and the shortest payback period; the FORC and DFORC show similar techno-economic performance and have advantages over the SF system. [ABSTRACT FROM AUTHOR]

The cadherin family plays a pivotal role in orchestrating synapse formation in the central nervous system. Cadherin-related family member 1 (CDHR1) is a photoreceptor-specific calmodulin belonging to the expansive cadherin superfamily. However, its role in traumatic brain injury (TBI) remains largely unknown. CDHR1 expression across various brain tissue sites was analyzed using the GSE104687 dataset. Employing a summary-data-based Mendelian Randomization (SMR) approach, integrated analyses were performed by amalgamating genome-wide association study abstracts from TBI with public data on expressed quantitative trait loci and DNA methylation QTL from both blood and diverse brain tissues. CDHR1 expression and localization in different brain tissues were meticulously delineated using western blotting, immunohistochemistry, and enzyme-linked immunosorbent assay. CDHR1 expression was consistently elevated in the TBI group compared to that in the sham group across multiple tissues. The inflammatory response emerged as a crucial biological mechanism, and pro-inflammatory and anti-inflammatory factors were not expressed in either group. Integrated SMR analyses encompassing both blood and brain tissues substantiated the heightened CDHR1 expression profiles, with methylation modifications emerging as potential contributing factors for increased TBI risk. This was corroborated by western blotting and immunohistochemistry, confirming augmented CDHR1 expression following TBI. This multi-omics-based genetic association study highlights the elevated TBI risk associated with CDHR1 expression coupled with putative methylation modifications. These findings provide compelling evidence for future targeted investigations and offer promising avenues for developing interventional therapies for TBI. Cadherin-related family member 1 as a potential risk factor for traumatic brain injury. [ABSTRACT FROM AUTHOR]

Background: Triglyceride glucose (TyG) is associated with stroke, atherosclerosis, and adverse clinical outcomes. However, its correlation with cerebrovascular disease (CVD) mortality remains unclear. This study aimed to investigate the relationship between TyG index and mortality in patients with CVD. Methods: Patient data sourced from the Medical Information Mart for Intensive Care -IV database were categorized based on TyG quartiles. Kaplan–Meier survival analysis was used to estimate survival disparities among the TyG subgroups. Cox proportional risk modeling was used to examine the association between the TyG index and mortality. Generalized summation models were applied to fit the smoothed curves. log-likelihood ratio test were used to analyze the non-linear relationship. Results: The study comprised 1,965 patients (50.18% were male). The 28-day and 90-day mortality rates were 20.10% and 24.48%, respectively. The TyG index exhibited a linear relationship with the 28-day mortality (Hazards ratio (HR), 1.16; 95% confidence interval (CI), 0.99–1.36) and the 90-day mortality (HR, 1.18; 95% CI, 1.02–1.37). In the TyG Q4 group, each 1 mg/dl increase was linked to a 35% rise in the risk of 28-day mortality and a 38% increase in the risk of 90-day mortality. Subgroup analyses highlighted a more substantial association between TyG index and 90-day mortality in the diabetic group. Conclusion: Our findings underscore the positive association between TyG and the 28- and 90-day mortality rates in patients with CVD. This insight may prove pivotal for identifying at-risk populations and enhancing risk prediction in the clinical management of CVD. [ABSTRACT FROM AUTHOR]

A numerical model has been constructed based on the solution of the magnetohydrodynamic equations within the framework of phase field algorithm to simulate the metal transfer process and to investigate the effect of power source dynamics on metal transfer and heat transfer behaviors in pulsed gas metal arc welding. Three typical kinds of power source dynamics (i.e. exponential, ideal square and trapezoidal waveform) using identical nominal pulsing parameters are considered and compared. The ideal square waveform with infinitely steep-sided pulse would lead to a higher detaching speed and an earlier detachment than other waveforms. Decrease in the response rate of the power source shows a retarding effect on the dynamic characteristics of the metal transfer, leading to a delay of detachment and a lower detaching speed. Moreover, this retarding effect is more and more significant as the response rate decreased and may even alter the transfer mode from one-drop-per-pulse to an undesired irregular pattern. Besides, a quantitative analysis of the heat fluxes into the electrode is further conducted, and the result shows that power source dynamics only has a quite slight influence on the heat transfer behavior. [ABSTRACT FROM AUTHOR]

Previously, we have studied protein adsorption and chromatographic behaviors on poly(ethylenimine) (PEI)-grafted Sepharose FF anion-exchange resins, and found that protein uptake rates increased greatly when PEI grafting density reached over a critical ionic capacity (cIC) due to the occurrence of the “chain delivery” effect. Moreover, by partial charge neutralization of starting resin FF-PEI-L740 (IC = 740 mmol/L, larger than the cIC) with sodium acetate to FF-PEI-R440, it exhibited a three-fold increase in uptake rate over FF-PEI-L740. In this work, to take the advantages of PEI and extend the applications of the PEI-grafted resins in cation-exchange chromatography, a series of cation exchangers of five different ICs were developed. First, the charged of FF-PEI-L740 was reversed from positive to negative by reaction with excess succinic anhydride, which created a cation-exchanger with an IC of 970 mmol/L (FF-FEI-C970). FF-PEI-C970 was further modified with ethanolamine for partial charge neutralizations, leading to the preparation of four charge-reduced cation exchangers with IC values (in mmol/L) of 780, 630, 560 and 430, which were denoted as FF-PEI-CR780, −CR630 −CR560 and −CR430, respectively. Protein adsorption and chromatographic behaviors were investigated using lysozyme (Lys) as the model protein. It was found that, the resins of high and moderate IC values (IC ≥ 560 mmol/L) afforded adsorption capacities up to over 230 mg/mL. Besides, the uptake rate, represented by the effective pore diffusivity ( D e/ D 0 ), exhibited significant increase from 0.067 (FF-PEI-C970 and FF-PEI-CR780) to 0.343 (FF-PEI-CR630 and FF-PEI-CR560) and then to 1.035 (FF-PEI-CR430) with decreasing IC. It was considered that decreasing IC led to the decreased protein binding sites (binding strength), which encouraged the occurrence of the “chain delivery” effect. Moreover, the resins of high and moderate IC values, particularly, the resins of moderate IC values (FF-PEI-CR630 and FF-PEI-CR560), presented both high adsorption capacities and uptake kinetics at 0–100 mmol/L NaCl. Besides, dynamic binding capacity achieved 150 mg/mL for the resins of moderate IC values at 0 mmol/L NaCl concentration, and afforded >110 mg/mL for the resin of high IC values at 0–100 mmol/L NaCl concentration. The results proved the excellent IEC performance of the PEI-derived cation exchangers. [ABSTRACT FROM AUTHOR]

It is important to obtain the targeted nanocarriers during cancer treatment. Herein, mannosylated liposomes encapsulating carbon dots (CDs) are provided for targeted recognition of liver cancer HepG2 cells, which is based on the specific interaction between D -mannose and glycoprotein on the surface of HepG2 cells. CDs were prepared by hydrothermal method. Then, they were encapsulated into liposomes by hydrophobic force. The encapsulation of CDs into liposomes increases their stability and fluorescence intensity. Furthermore, D -mannose can also be inserted into liposomes by the aldehyde amine reaction between aldehyde groups of mannose molecules and amino groups of liposomes. The obtained D -mannose-CDs-liposomes (Man-CDs-liposomes) exhibit selectively tracking and efficiently labelling for cancer cells. The work highlights the potential application of CDs for bioimaging and diagnostic. [ABSTRACT FROM AUTHOR]

We study in this paper the following singular Schrödinger-Kirchhoff-type problem with critical exponent -a+b∫Ω∇u2dxΔu+u=Q(x)u5+μxα-2u+f(x)(λ/uγ) in Ω,u=0 on ∂Ω, where a,b>0 are constants, Ω⊂R3 is a smooth bounded domain, 0<α<1, λ>0 is a real parameter, γ∈(0,1) is a constant, and 0<μ

In this work, Bi 0.5 (Na 0.82 K 0.18 ) 0.5 Ti 1– x (Mg 1/3 Nb 2/3 ) x O 3 (BNKT– x MN) lead-free ceramics with x  = 0.02–0.045 were fabricated by conventional solid state reaction sintering method. The effects of MN content on the phase structure, microstructure, dielectric, ferroelectric, energy storage and strain response were investigated. The MN diffuses into the lattice of BNKT matrix and forms solid solution. The MN doping pinches the hysteresis loops, and improves the energy storage density and efficiency. Meanwhile, the electric field-induced strain response with low hysteresis is also promoted. The B-site modification induces the transition from ferroelectric phase to ergodic relaxor. The significant enhancement in energy storage and strain response is attributed to the compositionally induced phase transition. A noticeable diffuse phase transition is confirmed by dielectric analysis. Thus, the energy storage and strain properties of BNKT ceramics can be modified by complex-ion induced phase transition. [ABSTRACT FROM AUTHOR]

Poly(ethylenimine) (PEI)-grafted Sepharose FF with an ionic capacity (IC) of 740 mmol/L (FF-PEI-L740) was modified with succinic anhydride, and six mix-charged resins of different ionic capacities (ICs) were synthesized [denoted as “Am-Cn” according to their anion exchange groups (amino groups) and cation exchange groups (carboxyl groups)]. Protein adsorption behaviors were investigated using bovine serum albumin (BSA) and lysozyme (LZM) as model proteins. The modification led to the net positive charge decrease to approximately zero (A320-C270), and then reversed the net charge to negative till the maximum negatively charge resin A20-C970. Adsorption capacity for BSA decreased from 205 ± 5 mg/mL (FF-PEI-L740) to 65 ± 3 mg/mL (A320-C270), but increased, for LZM, from 31 ± 1 mg/mL (A320-C270) to 281 ± 13 mg/mL (A20-C970) with increasing net negative charge. The uptake rate of BSA or LZM decreased with decreasing net positive charge or increasing net negative charge due to the decreased flexibility of the PEI chains brought from the increased electrostatic attraction or repulsion and/or tight binding due to the high net charge density. Effect of ionic strength (IS) showed that the resins with high net charge densities exhibited high adsorption capacities at high IS. Besides, dynamic binding capacity values achieved as high as 55 mg/mL for BSA and 143 mg/mL for LZM. Chromatographic experiments demonstrated favorable elution of bound proteins at NaCl lower than 370 mmol/L. [ABSTRACT FROM AUTHOR]

Rhodiola crenulata has been widely used as a health food, antifatigue and antidepressant in China and many other countries for centuries. However, to date the metabolism of it in vivo still remains unclear. In this study, UHPLC-FT-ICR MS was used to analyze the major components and their metabolites in rats after oral administration of Rhodiola crenulata for the first time. A total of 179 constituents, including 37 prototype compounds and 142 metabolites (89 phase I metabolites and 53 phase II metabolites) were tentatively identified. The metabolic pathways included hydroxylation, deglycosylation, dehydrogenation, glucuronidation and sulphate conjugation. In summary, this study showed an insight into the metabolism of Rhodiola crenulata in vivo , which may provide helpful chemical information for better understanding the multiple functions of it. And also, the developed method could be used as a reliable strategy to study the metabolic profile for other traditional chinese medicines. [ABSTRACT FROM AUTHOR]

This study aimed to establish a detection platform for ochratoxin A (OTA), a common mycotoxin contaminant of various food products. The detection platform is based on signal amplification by Exonuclease III (Exo III) and fluorescence quenching by gold nanoparticles (AuNPs). The aptamer recognizes and binds to OTA, thus leading to the formation of duplex DNA between the complimentary DNA (cDNA) strand and the signal probe. Exo III then digests the duplex DNA from the 3′ blunt terminus of the signal probe to liberate the fluorophore and release cDNA. The released cDNA then hybridizes with other signal probes to initiate a new cleavage reaction. Through this cyclic hybridization–hydrolysis process, an OTA molecule can trigger the cleavage of a large quantity of signal probes. Upon the addition of AuNPs, the fluorophore cannot be adsorbed and quenched, thus notably amplifying fluorescence. The designed aptasensor is highly selective for OTA with a low limit of detection (4.82 nM). The feasibility of the detection procedure and the applicability of the aptasensor were validated through the detection of OTA in spiked red wine without interference from the sample matrix. Results indicated that the aptasensor could be used to verify the effectiveness of mycotoxin-control strategies. [ABSTRACT FROM AUTHOR]

A numerical model is constructed based on the solution of the magnetohydrodynamic equations within the framework of phase field algorithm to simulate the metal transfer process and investigate the mechanism of the transition of metal transfer from globular to spray mode. Surface tension is the strongest driving force acting on the pendent droplet in globular transfer, while the governing force shifts to the electromagnetic pinch force in spray transfer. Driving force balance in the axial direction could be the indicator of detachment in globular transfer, while that force balance doesn’t exist in spray transfer. The condition for the transition from globular to spray transfer is that the local pressure at the root of the droplet caused by the electromagnetic pinch force exceeds the surface tension pressure at the droplet tip corresponding to a droplet radius equals to the wire radius. Compared with volume of fluid method, phase field method shows a more physically realistic estimation of the current path from the drop to the arc plasma and leads to a better agreement with experimental data. [ABSTRACT FROM AUTHOR]

The mechanism of the innovative adsorption based field emission hydrogen sensing technique is investigated from experimental and first-principles investigations. Hydrogen pressure from 10 −3 to 10 −7 Pa range could be detected. High carbon nanotube (CNT) crystallinity plays key role for the reduction of the effective work function from the dissociated hydrogen adsorption, leading to the field emission current increase. For CNT emitters with high dangling-bond (DB) type of defects/structures, the dissociated H adsorption occurs preferentially on the DB site with negligible work function variation. Joule heating & temperature rising is a core factor to assist the dissociated hydrogen adsorption with enhanced sensing effect. For work function sensitive CNT devices, operations under hydrogen & high temperature conditions may produce performance stability issue. [ABSTRACT FROM AUTHOR]

Gas metal arc welding (GMAW) using an alternating current waveform is usually termed as variable polarity GMAW (VP-GMAW), during which the electrode polarity switches between positive and negative periodically. The arc properties and the droplet transfer in VP-GMAW would be different from traditional direct current GMAW. In order to clarify the droplet transfer phenomena during a VP-GMAW process, a unified numerical model including the interaction between the arc plasma and the moving droplet is developed. The simulation results indicate that the arc plasma generated at electrode negative polarity shows a less constricted shape, a lower plasma temperature and velocity, compared to positive polarity. The resultant droplet is found to have a bigger size and a lower temperature than that of direct current gas metal arc welding with the same average welding current. Moreover, a quantitative analysis of the heat fluxes into the electrode is further conducted to explain the thermal mechanism for the differences in droplet properties between variable polarity and direct current gas metal arc welding. Finally, the simulated results are compared with the high-speed images, and the simulated and experiment results show good agreements. [ABSTRACT FROM AUTHOR]

In this paper, a graphene/GaAs near-infrared photodetector with Ag nanoparticles (NPs) is fabricated and the photoelectric characteristics of the device under near-infrared light is investigated. By spin-coating a 30 n m Ag NPs layer on the surface of the device, the local surface plasmon resonance (LSPR) of the Ag NPs can enhance the absorption of near-infrared light, thereby improving the sensitivity of the device. Compared with the device without Ag NPs, the responsivity of the device is significantly increased to 96 m A / W (increased by 1.6 times) under zero bias voltage at 808 n m near infrared light, the maximum detectivity of the device can be up to 4.72 × 1011 c m H z 1 / 2 W − 1 . In addition, the response time (τ r) and recovery time (τ f) of the device are 28.21 μ s /68.11 μ s. The quantum efficiency of the detector is increased from 37% to 84% compared with the device without Ag NPs. This result shows the graphene/GaAs photodetectors have a broad application prospect in the field of near-infrared detection. [ABSTRACT FROM AUTHOR]

• This study provides the latest evidence on the correlation between osteoporosis and cognitive impairment. • we used strict inclusion criteria to obtain a homogenous sample so that we could reduce bias because of unclear definitions as much as possible. • This study expands the understanding of osteoporosis and cognitive impairment. To systematically assess the association between osteoporosis and cognitive impairment, and to provide new light on the prevention of cognitive impairment in patients with osteoporosis. A comprehensive research of Embase, Cochrane Library, PubMed, Web of Science, CNKI, Wangfang Data and VIP was performed from inception to January 2022, using the search term 'osteoporosis' and 'cognitive impairment'. Literature screening, data extraction and quality evaluation were conducted by two reviewers independently, and meta-analysis was performed by RevMan 5.4 software. A total of 8 studies (136222 participants) were included. Meta-analysis showed that patients with osteoporosis had an increased risk of cognitive impairment [ OR =2.01, 95% CI (1.63–2.48), P< 0.01]. This initial meta-analysis had significant heterogeneity, and subgroup analysis suggested that potential heterogeneity in different study types, age and outcome indicators. Patients with osteoporosis are at increased risk of cognitive impairment, and osteoporosis intervention could prevent or delay the onset of cognitive impairment for those at risk. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting is considered a green and sustainable method of producing hydrogen energy. Herein, to pursue a highly efficient hydrogen evolution reaction, we fabricated high-performance electrocatalysts, by utilizing a bimetallic (Cu and Co) metal–organic framework to modify rGO through a one-step in situ approach. The synthesized CuCoOC@rGO presents a highly ordered structure with a defect-rich porous surface for the hydrogen evolution reaction (HER). Specifically, the appropriate adjustment of metal (Cu and Co), 1,3,5-benzenetricarboxylic acid (H3BTC), and rGO ratios leads to a well-defined morphology, which creates a defect-rich porous surface. Characterized by XRD, SEM, EDS, FT-IR spectroscopy, Raman spectroscopy, XPS, and BET, the morphology exposes more active sites, strong evidence for the promotion of electrocatalytic efficiency. Upon the analysis of the experimental data, the obtained CuCoOC@rGO catalyst exhibits excellent activity in alkaline media with a low overpotential of 120 mV at a current density of 10 mA cm−2, and a Tafel slope of 124 mV dec−1 for the hydrogen evolution reaction (HER). Guided by the structure–activity relationship, the superior HER activity of CuCoOC@rGO in alkaline electrolyte could originate from many sources, including: (1) as a self-supported substrate, CuCoOC@rGO not only leads to profitable electrical contact and mechanical stability but also firmly roots into the rGO without extra binders. (2) The highly ordered structure provides smooth ion and electron transport channels, which are conducive to electrolyte infiltration and gas release. (3) The abundance of defective pores on the surface of the nanoarrays, which offers more active sites for the catalytic process. This study provides new prospects for the rational design and fabrication of advanced hierarchical functional electrocatalysts for application in electrochemical energy devices. [ABSTRACT FROM AUTHOR]

Neuromedin S (NMS) has been identified as an endogenous ligand for FM-3/GPR66 and FM-4/TGR-1 which are NMU receptors NMUR1 and NMUR2, respectively. The NMS molecule is present in some peripheral tissues and the central nervous system (CNS), and it had been documented that NMS has fundamental and important roles in multiple physiological functions and processes such as circadian rhythm, energy balance, feeding behavior, stress responses and reproduction. The possible role of NMS in sexual development postnatally, however, is still obscure. This study aims to determine the change of NMS and its receptor gene expression in the reproductive axis of male Xiaomeishan pigs, postnatally. Firstly, the cDNA of the NMS and its receptors was cloned and sequenced. The results showed that there was a lack of 12 amino acids in the C-terminal of the male Xiaomeishan pig NMS amino-acid sequences compared with other animal species, but the main protein structure of prepro-NMS was high in homology. In addition, the nucleotide sequence and amino acids of the male Xiaomeishan pig’s NMUR1 and NMUR2 had high homology. The NMS and NMUR2 mRNA in the male Xiaomeishan pig was detected in the reproductive axis at postnatal development stages, including postnatal day 3, 30, 60, 90 and 120, using real-time PCR and immunohistochemistry. The data showed that there were developmental changes in NMS and NMUR2 in the reproductive axis of the male Xiaomeishan pigs, postnatally, which suggested that NMS and NMUR2 might have a role in the development of the boar reproductive axis, but its regulatory mechanism remains to be elucidated. [ABSTRACT FROM AUTHOR]

It is important to control drug release and detect the distribution of drug molecules before and after release. In this work, liposome@AgAu nanocomposite is prepared for drug delivery, which not only can control drug release by near infrared laser irradiation but also can monitor drug molecules by surface enhanced Raman scattering (SERS) and fluorescence signal during the release process. The liposome@AgAu core/shell nanocomposite prepared by the galvanic replacement reaction (GRR) shows tunable localized surface plasmon resonance (LSPR) absorption peaks from visible to near-infrared region and good biocompatibility. Comparing to pure doxorubicin (DOX) molecules, liposome@AgAu nanocomposite loading DOX exhibit lower cytotoxicity by MTT assay. After loading into liposome@AgAu, the fluorescence signal of DOX disappear due to the fluorescence resonance energy transfer from DOX to metals shell. On the contrary, the SERS signal of DOX in liposome@AgAu is obviously increased. Furthermore, the liposome@AgAu nanocomposite shows photothermal conversion ability under resonance laser irradiation. Under 633 nm laser irradiation, the liposome@AgAu nanocomposite loading DOX can release drug molecules for killing cancer cell. Meanwhile, the fluorescence signal from DOX appears after drug release from liposome@AgAu, but the SERS signal is not obvious. Therefore, this nanocomposite can provide a platform for photothermal controllable drug release and optical signal targeting for drug molecules. [ABSTRACT FROM AUTHOR]

The artificial introduction and rapid expansion of Spartina alterniflora Loisel ( S. alterniflora ) have greatly changed the natural evolution of tidal flats, especially along the Jiangsu coast, China. The occurrence of an elevation gap at the seaward marsh margin (marsh-edge cliffs) manifests that tidal flats have experienced severe regional erosion and the state transformation from the smooth slope to the stepped profile. However, the mechanisms controlling the formation of marsh-edge cliffs and the state transformation of tidal flats remain elusive while the future evolution of a marsh-cliff-flat system is unclear. Here we show the rapid formation process of marsh-edge cliffs within less than five years in Yancheng Nature Reserve, Jiangsu coast, China, as a fantastic example for the first time, via examining the cross-shore topographic changes during 2008–2014 and investigating sediment characteristics, vegetation biomass, marsh deposition rate, currents and waves during 2013–2014. A one-dimension cross-shore model was used to estimate the relative predominance of waves and currents in response to the variations of tidal flat cross-shore profile and help interpret the formation of marsh-edge cliffs. The fast accretion of the marsh area after the introduction of S. alterniflora (approximately 4.3–5.3 cm/yr) accelerated the seaward shift of marsh margin, narrowing the width of bare flat; meanwhile, reduced sediment supply from offshore triggered the down-cutting of the lower bare flat (e.g., the maximum of about 0.5 m at the mean sea level from 2010 to 2011), strengthening wave actions to erode bare flat landward. These two processes jointly led to the predominance of waves (0.43–0.90 N/m 2 ) over currents (mostly < 0.40 N/m 2 ) on the upper bare flat, which is consistent with the numerical modeling outcomes. As a consequence, the bed slope increased from 0.6‰ in 2008 to 1.0‰ in 2014, being vulnerable to wave attacks. The vegetation-root bonding of underlying sediments and the wave breaking at the marsh margin finally facilitated the formation of marsh-edge cliffs during 2011–2013. The cliffs were roughly estimated to retreat 20–110 m during 2013–2014. The future evolution of tidal flat accompanied by the continuous backward shifting of cliffs, the initiation and seaward spread of new marsh area, and the formation of new marsh-edge cliffs, resemble the hysteresis effect, as seaward advance and backward erosion will take almost equivalent time of nearly 9–50 years. This hysteresis effect of tidal flat evolution might further alter the local biological community structure and the pathway of coastal organic carbon flows. [ABSTRACT FROM AUTHOR]

In the study, the crack initiation and propagation behaviors of Ni-based GH3536 manufactured by selective laser melting (SLM) are quantified by the absorbed impact energy and the dynamic crack resistance curves. It is found that the SLM fabricated alloy exhibited slightly lower strength but much higher dynamic fracture toughness along the building direction, compared to those along transverse directions and the hot-rolled counterpart. The microstructure and defects of the SLM GH3536 alloywere characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), electron back-scattered diffraction (EBSD) and micro-computer tomography (μ-CT). Furthermore, the correlation between microstructure anisotropy and dynamic fracture behaviors are explored by the KAM, fractography and crack trajectories analyses. It is concluded that the anisotropy related to dynamic fracture mechanism of GH3536 alloy manufactured by SLM can be attributed to the 'weakest link' interface due to the laser melted pool geometry, the grain boundary or dendrite, which is strongly dependent on the relative orientation difference between the building direction and the crack plane. • The obvious anisotropy of SLM GH3536 in terms of tensile properties and fracture toughness was demonstrated. • The characteristic fracture behaviors were quantified by the absorbed impact energy and J -R curves. • The correlation between microstructure anisotropy on tensile and dynamic fracture behaviors were explored. [ABSTRACT FROM AUTHOR]