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The 2219 aluminum alloy thin-walled complex components manufactured by spin forming are frequently applied to the bottom end of rocket fuel tanks. However, fracture and quality problems (large part-mold contact gap, low roundness, thickness accuracy) are prone to occur during their multi-pass spin forming. While the material anisotropy, complicated components geometry and the complex stress state evolution make it difficult to obtain the appropriate forming process parameters in spin forming. With the help of finite element methods, it is possible to solve this difficulty. Thus, based on the anisotropic Barlat89 yield function and the DF2016 fracture criterion, a spin forming finite element model considering material anisotropy and damage evolution is established first for the components. Then, a method by using multi-pass involute spinning track with variable diameter base circle to form the components is proposed, and also the spinning passes are determined. Finally, taking the non-fracture as the constraint condition and the forming quality indexes (part-mold contact gap, roundness, and thickness accuracy) as the optimization objectives, a multi-objective optimization model based on orthogonal experimental design and response surface model is established. The optimized process parameters are solved and determined by a combination of the Archive-Based Micro Genetic Algorithm, and the optimized results are verified by the experiments. [ABSTRACT FROM AUTHOR]

Al matrix composites (AMCs) are innovative materials prepared by introducing various reinforcements into Al alloys using suitable processes. Traditional particle‐reinforced AMCs usually have high strength but poor interfacial bonding, resulting in low plasticity. Researchers are attempting to solve this problem by identifying more proper reinforcing particles. High‐entropy alloys (HEAs) with excellent mechanical properties including high strength, ductility, and wear resistance are becoming attractive candidates for the reinforcement of Al alloys. The HEAs‐reinforced AMCs (HEAs@AMCs) combine the lightweight property of Al alloys and superior mechanical properties of HEAs. In this article, a comprehensive overview is provided on the HEAs@AMCs, starting with an introduction to the properties of HEAs, followed by the design principle of HEAs for the metal matrix composites. After that, the preparation, microstructure, and mechanical properties of the HEAs@AMCs are examined. In addition, the effects of HEAs on the microstructure and mechanical properties of the HEAs@AMCs are explored. [ABSTRACT FROM AUTHOR]

The field of ecological environment health is developing continuously in our country, and it has already formed a well-developed education system and curriculum chain. However, it still lacks an experimental teaching system in laboratories to match the theoretical education in classrooms. Such a lack brings challenges in educating professionals integrated with innovative spirits and practical abilities. Caenorhabditis elegans has solid biological background information and is a model organism in the fields of life science and ecological environmental health. An experimental teaching system is established with C. elegans in the present study. It includes preparation of culture medium, microscopic observation, individual development, reproduction, total protein contents, enzyme activities and also gene expression levels. The overall contents strongly match the theoretical contents in microbiology, biochemistry, environmental toxicology and ecological toxicology. The experimental teaching system can improve the students' capacities in practical operation and experimental design, which will pave ways for their innovative spirits and practical abilities to solve scientific problems in the future. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) belong to emerging pollutants, and their hormesis earned particular attentions on their ecological impacts at low concentrations with long-term exposure. As one representative IL, N-ethylpyridinium bromide ([epyr]Br) was chosen as the target chemical. Its reproductive toxicities on Caenorhabditis elegans were determined with multi- and trans-generational exposure arrangements, and effects on the metabolites and enzyme activities in lipid metabolism were explored to elucidate the mechanisms. In the multi-generational exposure over 11 consecutive generations, [epyr]Br at 0.53 mg⋅L-1 caused stimulation on the reproduction in F1, F2, F3, F7, F8, F9 and F10, and provoked inhibition in F6 and F11. At 53 mg⋅L-1, it caused greater inhibitions in more generations than at 0.53 mg⋅L-1. In the trans-generational influences, [epyr]Br at both concentrations caused significant residual inhibition in the first non-exposed offspring of F1 (i.e., T3). Meanwhile, the residual effects of [epyr]Br exposure at the low concentration in the first non-exposed offspring of F11 (i.e., T3') showed stimulation, and those at the high did not show significant residual effects. The effects of [epyr]Br on the lipid metabolites, e.g., triacylglycerol (TG) and acetyl-CoA (ACA), and those on the activities of enzymes, e.g., glycerol-3-phosphate acyltrans-ferases (GPAT) and carnitine palmitoyl transferase (CPT), also showed oscillation between stimulation and inhibition over generations. Moreover, close relationships were found among the effects of [epyr]Br on the bio-indicators and also between the biochemical effects and the reproductive toxicities with influences by the exposure concentrations. In T3 and T3', [epyr] also showed significant residual effects on the biochemical indicators. Summing up, the reproductive toxicities of [epyr]Br in multi-generational exposure scenario and the residual effects in the trans-generational scenario were closely connected to effects on the lipid metabolism with influences by exposure concentrations. [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs) raised serious concerns on their health risk due to their toxicities. However, toxicities of low‐molecular‐weight PAEs, for example, dimethyl phthalates (DMPs), remained poorly investigated. In the present study, the reproductive toxicities of dimethyl (o‐)phthalate (DMOP), dimethyl (p‐)phthalate (DMPP), and dimethyl (m‐)phthalate (DMMP) were measured on Caenorhabditis elegans with mechanical exploration. Results showed that DMPP, DMOP, and DMMP commonly inhibited the total reproduction while stimulated lifespan, showing trade‐off effects. In effects on gene expressions, DMPP, DMOP, and DMMP caused different regulations on the expressions of vab‐1, ceh‐18, and gsa‐1 which are involved in oocyte growth, ovulation, and maturation. Meanwhile, they commonly downregulated those of rme‐2 and rcy‐4 that regulate germ cells and gonads and lipid metabolism in oocytes. Moreover, the effects on biochemicals that regulate reproductive processes showed alteration between stimulation and inhibition over life stages. In addition, effects at apical, biochemical, and molecular levels clearly showed the structure influences on the toxicities. Summing up, reproductive toxicities of DMPs depended on the exposure life stages and also the chemical structures. [ABSTRACT FROM AUTHOR]

The reaction of 2‐alkynylanilines with phenyliodonium bis(trifluoroacetate) (PIFA) and diaryl ditellurides was found to conveniently afford the corresponding 3‐aryltelluroindoles via oxidative cyclization/tellurolation. A plausible mechanism involving the in situ formation of the reactive ArTeOCOCF3 from the reaction of PIFA and diaryl ditellurides, and the subsequent oxidative C−N/C−Te bond formations was postulated. [ABSTRACT FROM AUTHOR]

In this work, nano porous materials NiCuCoMn@TMOs were prepared by melt-spining and chemical delloying methods, and R-NiCuCoMn@TMOs were further prepared through heat treatment. The characterization of the material was analyzed by X-ray diffraction, scanning electron microscopy, and Xray photoelectron spectroscopy. The electrochemical performance testing of the electrodes was tested. As an anode material for lithium-ion batteries, R-NiCuCoMn@TMOs has a high capacity (394.9 mAh/g) at a current density of 0.1 A/g and exhibits an excellent capacity retention of 97.53% after 200 cycles. The material after heat treatment has the more abundant vacancies, lower charge transfer resistance (38 Ω) and better rate capability (with a specific capacity of 141.1 mAh/g at a current density of 2 A/g). Unique nano porous structure provides rich active site for reaction. The synergetic effect of multiple metal cations with different radius, valence states and reaction potentials makes R-NiCuCoMn@TMOs have a good volume tolerance to accommodate the volume change during the lithium-deintercalation process, and display a superior electrochemical performance. In addition, the raw material reserves of the electrode material are abundant, the price is low, and it is easy to realize mass production. This work provides a new idea for simple multielement transition metal oxide anode materials designing. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the predictive value of 18F‐FDG PET/CT for pathological response after neoadjuvant immunochemotherapy (NICT) in patients with esophageal squamous cell carcinoma (ESCC). Methods: The clinical data of 54 patients with ESCC who underwent two cycles of NICT followed by surgery were retrospectively analyzed. NICT consisted of PD‐1 blockade therapy combined with chemotherapy. 18F‐FDG PET/CT scans were performed before and after NICT. The pathological results after surgery were used to assess the degree of pathological response. The scan parameters of 18F‐FDG PET/CT and their changes before and after NICT were compared with the pathological response. Results: Among the 54 patients, 10 (18.5%) achieved complete pathological response (pCR) and 21 (38.9%) achieved major pathological response (MPR). The post‐NICT scan parameters and their changes were significantly associated with the pathological response. In addition, the values of the changes in the scanned parameters before and after treatment can further predict the pathological response of the patient. Conclusion: 18F‐FDG PET/CT is a useful tool to evaluate the efficacy of NICT and predict pathological response in patients with ESCC. The post‐NICT scan parameters and their changes can help identify patients who are likely to achieve pCR or MPR. [ABSTRACT FROM AUTHOR]

TiO2 materials are considered one of the promising candidates for lithium/sodium-ion batteries (L/SIBs) due to its excellent safety and abundant resources. However, the low ion diffusion coefficient becomes a bottleneck in restrict its development. In this work, three-dimensional (3D) porous hydrangea-shaped anatase TiO2 (ATO) was synthesized through the synergistic effect of de-alloying and SO42− induced chemical synthesis. During the chemical synthesis process, SO42− and TiO62− octahedra are bound by static electricity, as the spatial effect of SO42− can influence the octahedral arrangement in favor of precipitating anatase TiO2. In the SIBs, ATO as anode material provided an excellent capacity of 190 mAh g−1 after 100 cycles at a current density of 50 mA g−1. Electrochemical kinetic tests show that the pseudocapacitive behavior contributes to 86% of the capacity at a scan rate of 1 mV s−1, mainly due to the high specific surface area provided by its unique microstructure, and also shows excellent electrochemical performance in the LIBs tests. This study provides a novel strategy for the simple and large-scale production of TiO2 anode materials with high-performance L/SIBs. [ABSTRACT FROM AUTHOR]

Geminal and vicinal borosilanes are useful building blocks in synthetic chemistry and material science. Hydrosilylation/hydroborylation of unsaturated systems offer expedient access to these motifs. In contrast to the well-established transition-metal-catalyzed methods, radical approaches are rarely explored. Herein we report the synthesis of geminal borosilanes from α-selective hydrosilylation of alkenyl boronates via photoinduced hydrogen atom transfer (HAT) catalysis. Mechanistic studies implicate that the α-selectivity originates from a kinetically favored radical addition and an energetically favored HAT process. We further demonstrate selective synthesis of vicinal borosilanes through hydrosilylation of allyl boronates via 1,2-boron radical migration. These strategies exhibit broad scopes across primary, secondary, and tertiary silanes and various boron compounds. The synthetic utility is evidenced by access to multi-borosilanes in a diverse fashion and scaling up by continuous-flow synthesis. Geminal and vicinal borosilanes are useful building blocks in synthetic chemistry. But in contrast to the well-established transition-metal catalyzed methods, radical approaches are rarely explored. Here, the authors report the synthesis of geminal borosilanes from α-selective hydrosilylation of alkenyl boronates via photoinduced hydrogen atom transfer (HAT) catalysis [ABSTRACT FROM AUTHOR]

In recent years, atomic force microscopes have been used for cell transfection because of their high-precision micro-indentation mode; however, the insertion efficiency of the tip of AFM into cells is extremely low. In this study, NIH3T3 mouse fibroblast cells cultured on a flexible dish with micro-groove patterns were subjected to various substrate strains at 5%, 10%, 15%, and 20%. It was found that the cell stiffness depends on the prestress of the cell membrane, and that the insertion rate of AFM tips into the cell membrane is proportional to the stiffness through the AFM indentation experiment. The finite element analysis proves that prestress increases the bending stiffness of the cytoskeleton, allowing it to better support the cell membrane, which realizes the stress concentration in the contact area between the AFM tip and the cell membrane. The results indicate that the prestress contributes to the mechanical properties of the cell and suggest that the insertion efficiency could be greatly improved with an increase of the prestress of the cell membrane. [ABSTRACT FROM AUTHOR]

Organic chlorine pesticides (OCPs) and antibiotics represent persistent organic pollutants and emerging pollutants, respectively. They can coexist in various environmental matrix, while their combined effects were seldom explored. Lindane was chosen to represent OCPs, and sulfamethoxazole (SMX) and tetracycline hydrochloride (TET) were chosen to represent antibiotics. The present study focused on the influences on tumor migration which is essential for both carcinogenesis and cancer treatment and aimed to explore the effects of the binary mixtures on the model organism Drosophila melanogaster. The individual effects showed that lindane significantly enhanced the tumor migration from the eye and brain of the larvae to the ventral nerve cord (VNC) in the concentration range of 40 -100 ng-g-1( P<0.05). SMX enhanced the tumor migration at the highest concentration of 400 ng-g-1, while TET increased the tumor migration from 600 to 1 000 ng-g-1 with a concentration-dependence. The binary mixtures were designed by direct equipartition method. The binary mixtures that contained lindane and SMX or TET significantly enhanced the tumor migration, with a dependence on the lindane-s concentrations. Compared with the predicted effects by independent action (IA) model, the binary mixtures showed synergistic toxicity interactions. Determination on the antioxidant responses showed that, lindane, SMX, TET and the binary mixtures commonly increased reactive oxygen species (ROS) while decreased glutathione (GSH). The effects of binary mixtures containing lindane and SMX on tumor migration were negatively correlated with their influences on catalase (CAT) activities, while such correlation was not observed in the effects of mixtures containing lindane and TET. Such difference was attributed to the different effects of SMX and TET on the antioxidants. Moreover, the effects of binary mixtures containing lindane and SMX, and those containing lindane and TET showed different hierarchical clustering positions. The effects of binary mixtures containing lindane and SMX on tumor migration were closely connected with both ROS and superoxide dismutase (SOD), while those of binary mixtures containing lindane and TET were closely connected with ROS. Such differences supported the attribution to the individual effects of SMX or TET on the antioxidants and also indicated that the antibiotic types can influence the toxicity mechanism of the binary mixtures. [ABSTRACT FROM AUTHOR]

Regarding the difficulties in the assessment of innovation and entrepreneurship teaching capability currently like biased qualitative assessment and less nonlinear quantitative assessment and insufficient assessment efficiency, an assessment model of innovation and entrepreneurship education targeted at local University students on the foundation of the Back Propagation (BP) neural network is designed. First, the contents of the questionnaire are carefully designed, on whose basis the assessment index system is built. Then, a BP neural network model is utilized for the purpose of comprehensively evaluating the collected data. Lastly, we carry out a demonstration study on innovation and entrepreneurship education, whose results reveal the students' professional knowledge and skills, participation in national competitions, and centralized entrepreneurship training camp play a key role and have a profound effect on innovation and entrepreneurship capability. The evaluation system is able to effectively assess the actual effects of innovation and entrepreneurship education, direct teachers' instructional activity, as well as motivate students to learn and practice. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a kind of central nervous system (CNS) autoimmune disease, which mainly damages nerves, the brain, and the spinal cord. Recently, several clinical cases reported the relativity between Coronavirus Disease 2019 (COVID-19) and the development of MS, but the mechanism of how COVID-19 affects the occurrence of MS was still not clear. It is bioinformatics technology that we use to explore the potential association at the gene level. The genetic information related to the two diseases was collected from the DisGNET platform for functional protein network analysis and used STRING to identify the complete gene set. The protein–protein interaction (PPI) network was analyzed by STRING. Finally, in the GEO database, we selected peripheral blood mononuclear cell (PBMC) RNA sequencing data (GSE164805, GSE21942) from COVID-19 patients and MS patients to verify the potential cross mechanism between the two diseases. The similar gene set of immune or inflammation existed between the patients with COVID-19 and ones with MS, including L2RA, IFNG, IL1B, NLRP3, and TNF. Interaction network analysis among proteins revealed that IL1B, P2RX7, IFNB1, IFNB1, TNF, and CASP1 enhanced the network connectivity between the combined gene set of COVID-19 and MS associated with NOD-like receptor (NLR) signaling. The involvement of NLR signaling in both diseases was further confirmed by comparing peripheral blood monocyte samples from COVID-19 and MS patients. Activation of NLR signaling was found in both COVID-19 and MS. The PBMC samples analyses also indicated the involvement of the NLR signaling pathway. Taken together, our data analyses revealed that the NLR signaling pathway might play a critical role in the COVID-19-related MS. [ABSTRACT FROM AUTHOR]

Carbonaceous materials are considered strong candidates as anode materials for sodium‐ion batteries (SIBs), which are expected to play an indispensable role in the carbon‐neutral era. Herein, novel braided porous carbon fibres (BPCFs) are prepared using the chemical vapour deposition (CVD) method. The BPCFs possess interwoven porous structures and abundant vacancies. The growth mechanism of the BPCFs can be attributed to the polycrystalline transformation of the nanoporous copper catalyst in the early stage of CVD process. Density functional theory calculations suggest that the Na+ adsorption energies of the mono‐vacancy edges of the BPCFs (−1.22 and −1.09 eV) are lower than that of an ideal graphene layer (−0.68 eV), clarifying in detail the adsorption‐dominated sodium storage mechanism. Hence, the BPCFs as an anode material present an outstanding discharge capacity of 401 mAh g−1 at 0.1 A g−1 after 500 cycles. Remarkably, this BPCFs anode, under high‐mass‐loading of 5 mg cm−2, shows excellent long‐term cycling ability with a reversible capacity of 201 mAh g−1 at 10 A g−1 over 1000 cycles. This study provided a novel strategy for the development of high‐performance carbonaceous materials for SIBs. [ABSTRACT FROM AUTHOR]

The reaction of N -arylpropynamides with (dichloroiodo)benzene (PhICl2) and diselenides/disulfides resulted in a divergent synthesis of chalcogenylated quinolinones and spiro[4.5]trienes through intramolecular electrophilic cyclization and chalcogenylation. The chalcogenyl functional group was introduced by an electrophilic reactive organosulfenyl chloride or selenenyl chloride species, generated in situ from the reaction of disulfides/diselenides and PhICl2. Notably, the divergent cyclization pathways were determined by the substituent type on the aniline ring in N -arylpropynamide substrates. Substrates bearing a fluoro, methoxy or trifluoromethoxy group at the para -position of the aniline underwent an alternative spiralization pathway to give the 3-chalcogenylated spiro[4,5]trienones. [ABSTRACT FROM AUTHOR]

Catalyst support of air cathode requires stable structure and high specific surface area, due to the unique semi open structure of metal-air battery. Herein, we prepare a novel 3D Copper/Carbon film catalyst support with dual 3D porous structure by nonsolvent induced phase separation and heat treatment process. During the heat treatment process in inert atmosphere, copper atom diffuses and recrystallizes to form the 3D porous structure with the support of polyacrylonitrile, and the polyacrylonitrile is carbonized to construct superimposed 3D carbon networks. This dual 3D porous Copper/Carbon film shows a high specific surface area of 7.61 m2 g−1, suitable mesopores pore size (2–10 nm), good conductivity (2.2 Ω) and mechanical properties. The as-prepared composites are used as air-cathode in aluminum-air battery, which exhibits good water resistance and air permeability after 3604 s discharging process with KOH electrolyte. This novel catalyst support could provide stable three-dimensional structure for high performance nano-sized catalyst, which supplies a new solution to develop high performance metal-air battery. [ABSTRACT FROM AUTHOR]

Reactive organosulfenyl chlorides (ArSCl) or selenenyl chlorides (ArSeCl), generated in situ from the reaction of PhICl2 with diorganyl disulfides or diselenides, enable the intramolecular oxidative cyclization/chalcogenylation of β,γ-unsaturated oximes, leading to the formation of a series of chalcogenylated isooxazolines in good to excellent yield. [ABSTRACT FROM AUTHOR]

This report described that a series of 4‐chalcogenylated isoxazoles were readily synthesized from the one‐pot reaction of alkynone Z‐O‐methyloximes with (dichloroiodo)benzene (PhICl2) and diorganyl disulfides/diselenides under metal‐free conditions. The reaction process was enabled by the electrophilic organosulfenyl chloride (RSCl) or selenenyl chloride (RSeCl) species, which were generated in situ from the reaction of PhICl2 and diorganyl disulfides/diselenides. The striking feature of the approach is the in‐situ formation of the electrophilic RSCl or RSeCl species, thus markedly decreasing the total usage of electrophiles when compared with the existing methods. This method exhibited a good functional groups tolerance for both alkynone Z‐O‐methyloximes and diorganyl disulfides/diselenides and the reaction could proceed at room temperature under ambient atmosphere within a short time to afford a series of functionalized isoxazoles in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

A series of alkoxylated isobenzofuranones were conveniently synthesized from the reaction of 2-(1-arylvinyl)benzoic acids with PhI(OR)2, generated in situ from the reaction of iodosobenzene (PhIO) with alkyl alcohols. This hypervalent iodine mediated one-pot transformation is postulated to undergo a cascade reaction involving lactonization, 1,2-aryl migration and alkoxylation processes. The organocatalytic and chiral organoiodine-catalyzed asymmetric reactions of the current transformation were also probed. [ABSTRACT FROM AUTHOR]

Excessive inflammatory responses induced upon SARS-CoV-2 infection are associated with severe symptoms of COVID-19. Inflammasomes activated in response to SARS-CoV-2 infection are also associated with COVID-19 severity. Here, we show a distinct mechanism by which SARS-CoV-2 N protein promotes NLRP3 inflammasome activation to induce hyperinflammation. N protein facilitates maturation of proinflammatory cytokines and induces proinflammatory responses in cultured cells and mice. Mechanistically, N protein interacts directly with NLRP3 protein, promotes the binding of NLRP3 with ASC, and facilitates NLRP3 inflammasome assembly. More importantly, N protein aggravates lung injury, accelerates death in sepsis and acute inflammation mouse models, and promotes IL-1β and IL-6 activation in mice. Notably, N-induced lung injury and cytokine production are blocked by MCC950 (a specific inhibitor of NLRP3) and Ac-YVAD-cmk (an inhibitor of caspase-1). Therefore, this study reveals a distinct mechanism by which SARS-CoV-2 N protein promotes NLRP3 inflammasome activation and induces excessive inflammatory responses. SARS-CoV-2 infection has been shown to drive NLRP3 inflammasome activation and thereby cytokine storm, but how it does so is unclear. Here the authors show that the viral N protein can bind to NLRP3, resulting in enhanced interaction with ASC and thereby with the NLRP3 inflammasome. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) is a mosquito-borne pathogen that causes a spectrum of diseases including life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Vascular leakage is a common clinical crisis in DHF/DSS patients and highly associated with increased endothelial permeability. The presence of vascular leakage causes hypotension, circulatory failure, and disseminated intravascular coagulation as the disease progresses of DHF/DSS patients, which can lead to the death of patients. However, the mechanisms by which DENV infection caused the vascular leakage are not fully understood. This study reveals a distinct mechanism by which DENV induces endothelial permeability and vascular leakage in human endothelial cells and mice tissues. We initially show that DENV2 promotes the matrix metalloproteinase-9 (MMP-9) expression and secretion in DHF patients' sera, peripheral blood mononuclear cells (PBMCs), and macrophages. This study further reveals that DENV non-structural protein 1 (NS1) induces MMP-9 expression through activating the nuclear factor κB (NF-κB) signaling pathway. Additionally, NS1 facilitates the MMP-9 enzymatic activity, which alters the adhesion and tight junction and vascular leakage in human endothelial cells and mouse tissues. Moreover, NS1 recruits MMP-9 to interact with β-catenin and Zona occludens protein-1/2 (ZO-1 and ZO-2) and to degrade the important adhesion and tight junction proteins, thereby inducing endothelial hyperpermeability and vascular leakage in human endothelial cells and mouse tissues. Thus, we reveal that DENV NS1 and MMP-9 cooperatively induce vascular leakage by impairing endothelial cell adhesion and tight junction, and suggest that MMP-9 may serve as a potential target for the treatment of hypovolemia in DSS/DHF patients. Author summary: DENV is the most common mosquito-transmitted viral pathogen in humans. In general, DENV-infected patients are asymptomatic or have flu-like symptoms with fever and rash. However, in severe cases of DENV infection, the diseases may progress to dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), the leading causes of morbidity and mortality in school-age children in tropical and subtropical regions. DENV-induced vascular leakage is characterized by enhanced vascular permeability without morphological damage to the capillary endothelium. This study reveals a possible mechanism by which DENV NS1 and MMP-9 cooperatively induce vascular leakage. NS1 also recruits MMP-9 to degrade β-catenin, ZO-1, and ZO-2 that leads to intervene endothelial hyperpermeability in human endothelial cells and mouse vascular. Moreover, the authors further reveal that DENV activates NF-κB signaling pathway to induce MMP-9 expression in patients, mice, PBMC, and macrophages though NS1 protein. This study would provide new in signs into the pathogenesis of DENV infection, and suggest that MMP-9 may act as a drug target for the prevention and treatment of DENV-associated diseases. [ABSTRACT FROM AUTHOR]

Aims Hepatocyte growth factor-regulated tyrosine kinase substrate (Hgs), a key component of the endosomal sorting complex required for transport (ESCRT), has been implicated in many essential biological processes. However, the physiological role of endogenous Hgs in the vascular system has not previously been explored. Here, we have generated brain endothelial cell (EC) specific Hgs knockout mice to uncover the function of Hgs in EC polarity and cerebrovascular stability. Methods and results Knockout of Hgs in brain ECs led to impaired endothelial apicobasal polarity and brain vessel collapse in mice. We determined that Hgs is essential for recycling of vascular endothelial (VE)-cadherin to the plasma membrane, since loss of Hgs blocked trafficking of endocytosed VE-cadherin from early endosomes to recycling endosomes, and impaired the motility of recycling endosomes. Supportively, overexpression of the motor kinesin family member 13A (KIF13A) restored endosomal recycling and rescued abrogated polarized trafficking and distribution of VE-cadherin in Hgs knockdown ECs. Conclusion These data uncover a novel physiological function of Hgs and support an essential role for the ESCRT machinery in the maintenance of EC polarity and cerebrovascular stability. [ABSTRACT FROM AUTHOR]

Background: Poly-brominated diphenyl ethers (PBDEs) and heavy metals are persistent pollutants in Yangtze River basin, China and also around the globe. In the exposure reality, they may have sequential exposures and long-term outcomes. Yet, the effects combining these two aspects remained largely unexplored. At present, the effects of 2,2′,4,4′-tetra-brominated diphenyl ether (BDE47) and lead (Pb) on Caenorhabditis elegans were studied with two sequential arrangements. One was first exposure to BDE47 and then to Pb (or vice versa) in one generation, and the other one was an early exposure to BDE47 in the parent generation (F0) and then a later exposure to Pb in the offspring (F1) (or vice versa). Results: On growth, sequential Pb-BDE47 exposure caused inhibition in exposure but stimulation in recovery, showing similarity to individual Pb results. Meanwhile, the opposite sequential BDE47-Pb exposure showed inhibition in both exposure and recovery, similar to those of individual BDE47 results. On behavior, the effects of sequential exposure were significantly different from individual results without any similarity. In transgenerational effects, F0 Pb exposure with F1 BDE47 exposure (Pb-F1-BDE47) inhibited growth, similar to the transgenerational results of individual Pb exposure. Meanwhile, the recovery effects were similar to the transgenerational results of individual BDE47. At the same time, Pb-F1-BDE47 exposure significantly hindered the recovery of behavior while the opposite BDE47-F1-Pb exposure resulted in different results. The behavioral effects in F1 showed negative correlation with the contents of γ-aminobutyric acid (GABA), while those in F1 were positively correlated with the activities of acetylcholine esterase (AChE). Conclusions: Sequential exposure to BDE47 and Pb within one generation or over generations showed significant different effects from individual results. Further studies are still needed to investigate the toxicity patterns and underlying mechanisms. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) infection causes several diseases ranging from dengue fever to life-threatening dengue hemorrhagic fever and dengue shock syndrome characterized by endothelial dysfunction, vascular leakage, and shock. Here, we identify a potential mechanism by which DENV induces tissue injury and vascular leakage by promoting the activation of interleukin (IL)-1β. DENV facilitates IL-1β secretion in infected patients, mice, human peripheral blood mononuclear cells (PBMCs), mouse bone marrow-derived macrophages (BMDMs), and monocyte-differentiated macrophages (THP-1) via activating the NLRP3 inflammasome. The accumulated data suggest that IL-1β probably induces vascular leakage and tissue injury in interferon-alpha/beta receptor 1 deficient C57BL/6 mice (IFNAR –/– C57BL/6), whereas IL-1 receptor antagonist (IL-1RA) alleviates these effects of IL-1β. Finally, administration of recombinant IL-1β protein results in vascular leakage and tissue injury in C57BL/6 mice. Together, the accumulated results demonstrate that IL-1β contributes to DENV-associated pathology and suggest that IL-1RA acts as a potential agent for the treatment of DENV-associated diseases. [ABSTRACT FROM AUTHOR]

Surface nuclear magnetic resonance (SNMR) could provide direct insights for hydrological investigations but is often limited because of its low signal-to-noise ratio. Many types of residual noise remain after denoising procedures, including despiking, power harmonic noise cancellation, and random noise attenuation. This residual noise prevents the detection of valid signals, especially in strong noise environments, such as cities and industrial areas. In this work, a lock-in amplifier modeling recovery (LIAMR) method is proposed for extracting SNMR signals from high-level residual noise after denoising. The desired SNMR signals can be extracted directly by establishing a model of the SNMR signal passing through the lock-in amplifier and then transforming mathematically the output of the amplifier. The performance of the proposed method is tested on synthetic SNMR signals under varied average relaxation times, simulation noise at different levels, and field noise. Experiment results show that LIAMR can obtain good estimations of SNMR signal parameters with residual noise. Moreover, the proposed method can provide more precise parameters compared with traditional signal extraction methods. LIAMR provides theoretical support for the application of SNMR technology in strong noise environments. [ABSTRACT FROM AUTHOR]

Anthropogenic pressures, such as contaminant exposure, may affect stable isotope ratios in biota. These changes are driven by alterations in the nutrient allocation and metabolic pathways induced by specific stressors. In a controlled microcosm study with the amphipod Gammarus spp., we studied effects of the β-blocker propranolol on stable isotope signatures (δ15N and δ13C), elemental composition (%C and %N), and growth (protein content and body size) as well as biomarkers of oxidative status (antioxidant capacity, ORAC; lipid peroxidation, TBARS) and neurological activity (acetylcholinesterase, AChE). Based on the known effects of propranolol exposure on cellular functions, i.e., its mode of action (MOA), we expected to observe a lower scope for growth, accompanied by a decrease in protein deposition, oxidative processes and AChE inhibition, with a resulting increase in the isotopic signatures. The observed responses in growth, biochemical and elemental variables supported most of these predictions. In particular, an increase in %N was observed in the propranolol exposures, whereas both protein allocation and body size declined. Moreover, both ORAC and TBARS levels decreased with increasing propranolol concentration, with the decrease being more pronounced for TBARS, which indicates the prevalence of the antioxidative processes. These changes resulted in a significant increase of the δ15N and δ13C values in the propranolol-exposed animals compared to the control. These findings suggest that MOA of β-blockers may be used to predict sublethal effects in non-target species, including inhibited AChE activity, improved oxidative balance, and elevated stable isotope ratios. The latter also indicates that metabolism-driven responses to environmental contaminants can alter stable isotope signatures, which should be taken into account when interpreting trophic interactions in the food webs. [ABSTRACT FROM AUTHOR]

The dynamic characteristic has an important effect on the motion precision of a robot and dynamic feedforward control is an effective approach to reduce the effect. However, it is difficult to realize the accurate dynamic feedforward control in an industrial servo system and determine the feedforward coefficients. This paper proposes a method to realize the accurate dynamic feedforward control of a spray-painting robot for airplane wings with large workspace and time-varying dynamics. The basic control method is still the feedback control system with dynamic feedforward compensation, which is the most widely used in industrial field. The control parameters of the closed-loop feedback control system are designed based on atlas method. Considering that only the acceleration and velocity feedforward compensations are provided in an industrial servo system, the mapping relationship between the complete dynamic model and the velocity and acceleration compensators is investigated. Then, the method to realize the accurate feedforward compensation in the industrial servo system is presented based on the complete dynamic model. For a complex robot without an accurate dynamic model, the approach to realize the accurate feedforward compensation is also discussed. The experiment on a physical prototype validates the effect of the proposed methods. This paper is very helpful for the practical control of robots in an industrial field. [ABSTRACT FROM AUTHOR]

Earlier studies showed that toxicities of excessive metals lasted over generations. Yet, these studies mainly employed one-generation exposure, and the effects of multigenerational challenges need further studies. Presently, Caenorhabditis elegans were exposed to cadmium, copper, lead and zinc for four consecutive generations (G1 to G4) at environmental concentrations. The feeding, growth, initial reproduction, superoxide dismutase (SOD) and catalase (CAT) were determined. All data were represented in the percentage of that in control (POC), and POC in the control was normalized to 100%. In G1 and G2, the POC values in feeding, growth and initial reproduction were generally within 10% of the control (100%), indicating non-significant effects. The POC values in SOD and CAT were significantly higher than 100%, showing stimulatory effects. In G3 and G4, the POC values in feeding, growth and initial reproduction were significantly lower than 100%, showing inhibitory effects which were more severe in G4 than in G3. Meanwhile, SOD and CAT continuously showed stimulatory effects, and the stimulatory effects on SOD increased from G1 to G4. The effects with multigenerational challenges were different from those in one-generation exposure. The effects in later generations demonstrated the importance of multigenerational challenges in judging long-term influences of metals. [ABSTRACT FROM AUTHOR]

Image-based displacement measurement techniques are widely used for sensing the deformation of structures, and plays an increasing role in structural health monitoring owing to its benefit of non-contacting. In this study, a non-overlapping dual camera measurement model with the aid of global navigation satellite system (GNSS) is proposed to sense the three-dimensional (3D) displacements of high-rise structures. Each component of the dual camera system can measure a pair of displacement components of a target point in a 3D space, and its pose relative to the target can be obtained by combining a built-in inclinometer and a GNSS system. To eliminate the coupling of lateral and vertical displacements caused by the perspective projection, a homography-based transformation is introduced to correct the inclined image planes. In contrast to the stereo vision-based displacement measurement techniques, the proposed method does not require the overlapping of the field of views and the calibration of the vision geometry. Both simulation and experiment demonstrate the feasibility and correctness of the proposed method, heralding that it has a potential capacity in the field of remote health monitoring for high-rise buildings. [ABSTRACT FROM AUTHOR]

In this study, PCR-denaturing gradient gel electrophoresis (DGGE) was applied to analyze the microbial communities in lake sediments from Lake Xuanwu, Lake Mochou in Nanjing and Lake Taihu in Wuxi. Sediment samples from seven locations in three lakes were collected and their genomic DNAs were extracted. The DNA yields of the sediments of Lake Xuanwu and Lake Mochou were high (10 μg/g), while that of sediments in Lake Taihu was relatively low. After DNA purification, the 16S rDNA genes (V3 to V5 region) were amplified and the amplified DNA fragments were separated by parallel DGGE. The DGGE profiles showed that there were five common bands in all the lake sediment samples indicating that there were similarities among the populations of microorganisms in all the lake sediments. The DGGE profiles of Lake Xuanwu and Lake Mochou were similar and about 20 types of microorganisms were identified in the sediment samples of both lakes. These results suggest that the sediment samples of these two city lakes (Xuanwu, Mochou) have similar microbial communities. However, the DGGE profiles of sediment samples in Lake Taihu were significantly different from these two lakes. Furthermore, the DGGE profiles of sediment samples in different locations in Lake Taihu were also different, suggesting that the microbial communities in Lake Taihu are more diversified than those in Lake Xuanwu and Lake Mochou. The differences in microbial diversity may be caused by the different environmental conditions, such as redox potential, pH, and the concentrations of organic matters. Seven major bands of 16S rDNA genes fragments from the DGGE profiles of sediment samples were further re-amplified and sequenced. The results of sequencing analysis indicate that five sequences shared 99%–100% homology with known sequences ( Bacillus and Brevibacillus, uncultured bacteria), while the other two sequences shared 93%–96% homology with known sequences ( Acinetobacter, and Bacillus). The study shows that the PCR-DGGE technique combined with sequence analysis is a feasible and efficient method for the determination of microbial communities in sediment samples. [ABSTRACT FROM AUTHOR]

These authors contributed equally: Pan Pan, Miaomiao Shen, Zhenyang Yu. The original version of this Article omitted the following from the Acknowledgements: Science & Technology Planning Project of Guangdong Province Office of Education (2018KCXTD007, 2021XK16), Special project for the prevention and control of new crown pneumonia in Guangdong colleges and universities (2020KZDZX1060). [Extracted from the article]

Camera calibration is crucial for geometric vision-based three-dimensional (3D) deformation measurement tasks. Among existing calibration techniques, the one based on planar targets has attracted much attention in the community due to its flexibility and reliability. Our study proposes a calibration technique to obtain high-accuracy internal and external parameters based on low-cost ordinary planar patterns. The proposed method determines the optimal internal parameters for each camera by refining 3D coordinates of planar control points, where an analytic model of optics distortion is presented to enable lens distortion to be corrected directly in subsequent external calibration and underlying 3D reconstruction. External parameters are estimated by minimizing a bundle adjustment framework, which is carefully designed based on the proposed distortion correction model and depth parameterization. In contrast to the existing techniques, the proposed method is capable of obtaining a high-accuracy calibration with ordinary targets rather than the well-designed and fabricated ones. We experimented the proposed method with a calibration performance analysis and a displacement measurement; both results demonstrated the accuracy and robustness. [ABSTRACT FROM AUTHOR]

The magnetic resonance sounding (MRS) method is a non-invasive, efficient and advanced geophysical method for groundwater detection. However, the MRS signal received by the coil sensor is extremely susceptible to electromagnetic noise interference. In MRS data processing, random noise suppression of noisy MRS data is an important research aspect. We propose an approach for intensive sampling sparse reconstruction (ISSR) and kernel regression estimation (KRE) to suppress random noise. The approach is based on variable frequency sampling, numerical integration and statistical signal processing combined with kernel regression estimation. In order to realize the approach, we proposed three specific sparse reconstructions, namely rectangular sparse reconstruction, trapezoidal sparse reconstruction and Simpson sparse reconstruction. To solve the distortion of peaks and valleys after sparse reconstruction, we introduced the KRE to deal with the processed data by the ISSR. Further, the simulation and field experiments demonstrate that the ISSR-KRE approach is a feasible and effective way to suppress random noise. Besides, we find that rectangular sparse reconstruction and trapezoidal sparse reconstruction are superior to Simpson sparse reconstruction in terms of noise suppression effect, and sampling frequency is positively correlated with signal-to-noise improvement ratio (SNIR). In one case of field experiment, the standard deviation of noisy MRS data was reduced from 1200.80 nV to 570.01 nV by the ISSR-KRE approach. The proposed approach provides theoretical support for random noise suppression and contributes to the development of MRS instrument with low power consumption and high efficiency. In the future, we will integrate the approach into MRS instrument and attempt to utilize them to eliminate harmonic noise from power line. [ABSTRACT FROM AUTHOR]