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Spinal cord injury (SCI) results in neurological deficits below the level of injury, causing motor dysfunction and various severe multisystem complications. Rehabilitative training plays a crucial role in the recovery of individuals with SCI, and exoskeleton serves as an emerging and promising tool for rehabilitation, especially in promoting neuroplasticity and alleviating SCI-related complications. This article reviews the classifications and research progresses of medical exoskeletons designed for SCI patients and describes their performances in practical application separately. Meanwhile, we discuss their mechanisms for enhancing neuroplasticity and functional remodeling, as well as their palliative impacts on secondary complications. The potential trends in exoskeleton design are raised according to current progress and requirements on SCI rehabilitation. [ABSTRACT FROM AUTHOR]

Climate warming and biological invasion can interact to affect ecosystems, and the results of such interactions depend on whether invaders show physiological advantages in their responses to warming environments as compared with native species after the establishment and local adaptation. However, it has rarely been evaluated.The present study compared the heat tolerance of a globally invasive turtle, the red‐eared slider Trachemys scripta elegans, and two co‐occurring native turtle species in China, the Chinese soft‐shelled turtle Pelodiscus sinensis and Chinese pond turtle Mauremys reevesii, after acclimation in the same thermal environment. The expression patterns of heat shock factor 1 (HSF1), multiple heat shock proteins (HSPs) and telomere reverse transcriptase (TERT), and changes in relative telomere length (RTL) were then evaluated in liver and muscle of turtles under thermal stress.The results showed that T. scripta elegans had greater physiological resistance to heat than the co‐occurring native turtle species, and that this higher tolerance was accompanied by a higher temperature induction of the peak expression of inducible HSPs in liver and a higher onset temperature for the main inducible HSPs in muscle. During thermal stress, T. scripta elegans showed a better ability to maintain the expression levels of TERT under extremely hot conditions, whereas high temperatures inhibited TERT in muscles of native turtle species. Meanwhile, thermal stress did not cause telomere erosion in any of the three turtle species and some treatments can lead to slightly longer telomeres in T. scripta elegans or M. reevesii.Overall, the invasive turtle species showed higher heat tolerance and physiological advantages in enduring hot weather in comparison to the co‐occurring native turtle species. This may favour these invaders in situations of climate warming. Our study highlights the role of physiological adaptations displayed by invaders in achieving advantages over native species under climate change. [ABSTRACT FROM AUTHOR]

To investigate the degradation law of the mechanical properties of corroded steel, the standard specimens from machining steel members in service for 9 years in an industrial environment were subjected to tensile tests. The influences of different degrees and types of corrosion on the fracture path, stress-strain curve, and mechanical properties of specimens were discussed. Finally, the damage constitutive model of corroded steel was established based on the damage mechanics theory. The results showed that the failure modes of corroded specimens were related to the degrees and types of corrosion. The fracture morphology of specimens with general corrosion were step-like and the fractures of steel were uneven. However, those with local corrosion were mainly flat-like, and the fracture path was along the cross section where the larger corrosion pits were located. The fracture path of the specimen was related to the interaction of the corroded surface and internal material defects (holes). Meanwhile, with the increase of corrosion degree, the yield platform of stress-strain curve gradually became shorter, or even disappeared, and the ultimate strain and elongation at break decreased, implying that the ductility of steel became worse. Ultimately, the good agreement between the curves of the model and test indicated that the damage model could reflect the damage development process of corroded steel in the tensile process better. Corrosion damage resulted in the decrease in the damage threshold, and the damage variable D decreased by the time fracture occurred and the maximum reduction rate was up to 62.5%. [ABSTRACT FROM AUTHOR]

Regulating farmers' choice of agricultural production service (APS) contracts can help maintain the stability of transactions, enhance agricultural production efficiency, protect farmers' rights and welfare, stimulate the healthy and sustainable development of service organizations, and promote the economic benefits of agriculture. Under the uncertainty of risk (RU), farmers' willingness to sign a regulated service contract after purchasing APS is a key factor in reaching an efficient and high-quality partnership. Based on the survey data of the black soil area in northeastern China, this study uses the Heckman two-stage model and analyzes it under the logical framework of APS purchases and contractual choice behavior (CCB) under the role of RU. The main findings are as follows. First, the RU has a significant "inducing" effect on farmers' CCB, and the higher the RU, the more farmers tend to make formal written contracts; among them, each unit increase in business risk increases farmers' choice of written contracts by 0.797 units, which is an important factor affecting CCB. Second, farmers' personal trust level played a positive moderating role in influencing CCB. Compared to the low trust level group, farmers in the high trust level group had a diminished degree of influence on CCB, but the intensity was relatively weak. Third, farmers' personal, family, and social characteristics all influence their behavioral decision-making processes. In order to reduce the risk level of cooperation between farmers and service providers, which can promote the standardization of cooperation contracts, this study suggests that the government should use the publication of manuals and other forms to carry out legal literacy, promote labor market information transparency, reduce service risks, and enhance the effectiveness of the linkage between farmers and service providers. [ABSTRACT FROM AUTHOR]

Many scholars have conducted in-depth studies on the research area of black soil conservation (BSC) and produced fruitful research results, but there is still a lack of scientific quantitative analysis and objective comprehensive evaluation of the research results. In order to grasp and clarify the current status of BSC research, we explored the trending topics and frontier issues in this research field, as well as the overall evolution trend from 1983 to 2022. Based on the publication information of BSC topics in the core database of Web of Science (WOS), this study utilized the superior tools in two major bibliometric software; they are the VOSviewer and CiteSpace to draw visual maps, such as collaboration networks and keyword co-occurrence maps, to further analyze the research progress and frontiers. The results are as follows: First, research on BSC began in 1983 and can be divided into three phases: the period of nascent research, steady development, and rapid growth. The subject increasingly became an area of research focus in academia, but gradually produced signs of intersection with other disciplines, such as agronomy, biology, and economics. Second, the distribution of research institutions and countries has become more concentrated, forming geographically small research clusters in typical black soil area countries, such as Russia and China, where the centrality of research institutions is higher than 0.20. Research networks have also been initially established between developed and developing countries, such as the United States and China, with a high centrality close to 0.50. Third, the research content is increasingly cross-cutting and systematic, and the research focus can be divided into five major areas, such as black soil distribution and physical and chemical characteristics. Fourth, the research areas cover agronomy, chemistry, geography and other levels, and a more systematic research system has been formed. In the future, it is still necessary to strengthen the establishment of data monitoring systems in black soil areas, the improvement of black soil information database, the assertion of conservation tillage technology and the strengthening of extreme climate early warning network to maintain the soil nutrient content and to guarantee the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

There is a growing demand for the development of epoxy resin modified with biomaterials, aiming to achieve high toughness. Herein, chitosan crosslinked epoxy resin (CE) was synthesized by diisocyanate as a bridge. With 4,4′-diamino-diphenylmethane (DDM) as the curing agent, thanks to the unique cross-linking structure of the CE resin and the presence of carbamate groups, the cured CE/DDM exhibited superior properties compared to commercially available epoxy resin (E51). The tensile strength of the cured CE-3/DDM reached 90.17 MPa, the elongation at break was 11.2 %, and the critical stress intensity factor (K IC) measured 1.78 MPa m1/2. These values were 21.4 %, 151.6 %, and 81.6 % higher than those of the cured E51/DDM, respectively. It is worth noting that the addition of biomass material chitosan did not reduce the thermal stability of the resin. Additionally, the CE coatings on the metal substrate exhibited exceptional corrosion resistance, as evidenced by higher impedance values in electrochemical impedance spectroscopy (EIS) and polarization voltages in the Tafel curve compared to those of the E51 coating. This study opens up a novel approach to modifying epoxy resin with biomass materials with high toughness and corrosion resistance, without sacrificing other performance. [Display omitted] • Chitosan crosslinked epoxy resin was synthesized by chemical cross-linking method. • A new way of toughening epoxy resin with biomaterials was developed. • The unique crosslinking structure of the resins enhanced toughness and strength. • The synthetic resin coatings showed good corrosion resistance on the metal matrix. [ABSTRACT FROM AUTHOR]

• FC featuring fibrous topography and superior hardness is fabricated by cyclic oxidation and grinding. • CCF exhibits higher hardness (increased by 22.65%) and wear resistance (increased by 52.1%), compared to CCE. • The ideal mechanically-bonded Cu/C interface and higher strength of the matrix are formed on CCF. Fibrous copper powder (FC) featuring fibrous topography is fabricated by water-atomization, cyclic oxidation, and grinding. Prominent hardness and deformation resistance of FC are identified compared to electrolytic copper powders (EC). Copper/graphite metallic composites with FC (CCF) are endowed with higher hardness (increased by 22.65 %) and tensile modulus (increased by 135.4 %). The CCF shows stable friction coefficient, and the wear resistance is improved by 52.1 %, ascribed to the ideal mechanically-bonded Cu/ graphite interfaces and higher strength of the matrix. The integral grains on the matrix and approximately 5 μm stress layer around the Cu/graphite interfaces of CCF contribute to excellent mechanically-bonded, where the nano-hardness and elastic modulus of CCF are increased by around 300 % compared to CCE, exerting superiority of the mechanically-bonded Cu/ graphite interfaces. [ABSTRACT FROM AUTHOR]

Abstract Objective Stem cell transplantation is a promising tool to treat burn injuries. However, the inflammatory microenvironment in damaged skin limits the efficiency of stem cell-based therapy via poorly understood mechanisms. The aim of our study is to explore the contribution and mechanism of Sirtuin-1 (Sirt1) in TNFα-mediated inflammatory stress in hair follicle stem cells (HFSCs). Methods Cellular viability was determined using the MTT assay, TUNEL staining, western blot analysis and LDH release assay. Adenovirus-loaded Sirt1 was transduced into HFSCs to overexpress Sirt1 in the presence of TNFα. Mitochondrial function was determined using JC-1 staining, mitochondrial ROS staining, immunofluorescence staining and western blotting. Results Sirt1 was downregulated in response to the TNFα treatment. Additionally, TNFα stress reduced the viability, mobility and proliferation of HFSCs, and these effects were reversed by the overexpression of Sirt1. At the molecular level, Sirt1 overexpression attenuated TNFα-mediated mitochondrial damage, as evidenced by increased mitochondrial energy metabolism, decreased mitochondrial ROS generation, stabilized mitochondrial potential and blockage of the mitochondrial apoptotic pathway. Furthermore, Sirt1 modulated mitochondrial homeostasis by activating the MAPK-ERK-Mfn2 axis; inhibition of this pathway abrogated the protective effects of Sirt1 on HFSC survival, migration and proliferation. Significance Based on our results, the inflammatory stress-mediated HFSC injury may be associated with a decrease in Sirt1 expression and subsequent mitochondrial dysfunction. Accordingly, strategies designed to enhance Sirt1 expression would be an effective approach to enhance the survival of HFSCs in the inflammatory microenvironment. [ABSTRACT FROM AUTHOR]

The remote excitation and remote-controlling of the localized surface plasmon resonance (LSPR) in a heterotype and hollow gold nanosheet (HGNS) is studied using FDTD simulations. The heterotype HGNS contains an equilateral and hollow triangle in the center of a special hexagon, which forms a so-called hexagon–triangle (H–T) heterotype HGNS. If we focus the incident-exciting laser on one of the vertexes of the center triangle, the LSPR could be achieved among other remote vertexes of the outer hexagon. The LSPR wavelength and peak intensity depend sensitively on factors such as the polarization of the incident light, the size and symmetry of the H–T heterotype structure, etc. Several groups of the optimized parameters were screened out from numerous FDTD calculations, which help to further obtain some significant polar plots of the polarization-dependent LSPR peak intensity with two-petal, four-petal or six-petal patterns. Remarkably, based on these polar plots, the on-off switching of the LSPR coupled among four HGNS hotspots could be remote-controlled simply via only one polarized light, which shows promise for its potential application in remote-controllable surface-enhanced Raman scattering (SERS), optical interconnects and multi-channel waveguide switches. [ABSTRACT FROM AUTHOR]

With the fast growing of new energy technologies, the proportion of distributed renewable energy sources dominated by wind and light energy in the microgrid continues to increase. However, the uncertainty and randomness of energy itself bring challenges to the stable operation of the power system. Microgrid load forecasting with high accuracy is the key means to handle the above problems. It can provide help for power grid dispatching and decision-making, optimize resource allocation, reduce operation cost, and ensure system safety. In this paper, a load-forecasting algorithm for microgrid based on improved long short-term memory neural network (LSTM) is proposed. Firstly, the criticality analysis of load influencing factors is carried out, and the clustering classification and weight calculation are completed. Then, the input data is preprocessed to ensure the quality of database. Secondly, the LSTM gets improved from three aspects: multilayer convolution channel, lookahead optimizer, and AM weight. And a complete forecasting model is designed to accomplish the load forecasting. Finally, based on the data of a local microgrid in Zhejiang Province, China, simulation experiments are conducted. The results are quantitatively compared with other forecasting algorithms to verify the accuracy and superiority of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The high brittleness of epoxy resin at cryogenic temperature restricts their wide application in cryogenic engineering. In this study, polyhedral oligomeric silsesquioxane (POSS) with -Si-O-Si- molecular chains were synthesized, and the mechanical properties of diglycidyl ether of bisphenol A (E51 epoxy resin) were significantly enhanced at room temperature (RT) by incorporating a 4% POSS and curing agent 4,4′-diamino-diphenylmethane (DDM) as the E51/POSS/DDM resin system. Subsequently, by adding different contents of epoxidation hydroxyl-terminated polybutadiene (EHTPB) into the E51/POSS/DDM resin system, the EHTPB-E51/POSS/DDM resin system was prepared. The investigation into the impact of EHTPB content on the mechanical properties of EHTPB-E51/POSS/DDM resin system at room temperature (RT) revealed that EHTPB-E51/POSS/DDM resin system with 10% EHTPB exhibited the most favorable results. Specifically, the elongation at break, flexural strength, and critical stress intensity factor (K IC) were measured to be 6.82%, 143.75 MPa, and 1.83 MPa m1/2, respectively. These values demonstrated a notable improvement of 53.3%, 26.9%, and 86.7% compared to those for the E51/DDM resin system. Concurrently, at 77 K, the elongation at break and critical stress intensity factor (K IC) increased by 37.8% and 73.5%, respectively. The toughening mechanism of the prepared EHTPB-E51/POSS/DDM resin system was further explored through resin-curing cross-linking simulation networks and SEM images of the fracture surface of resin samples. The study of EHTPB and POSS synergistically toughened epoxy resin provided a new efficient method to prepare epoxy resins with high toughness at low temperatures. [Display omitted] • Cross-linkable EHTPB and POSS synergistically improve the E51 toughness. • K IC and G IC values are 73.5% and 258.6% higher than the E51/DDM at 77 K. • Resin-cured crosslinking simulation network analyzed the toughening mechanism. [ABSTRACT FROM AUTHOR]

A novel low-alloy ultrahigh-strength steel featuring excellent mechanical properties and comprising a nanolath structure was fabricated in this work using a quenching–partitioning–tempering (Q-P-T) process. The Q-P-T process comprised direct quenching and an isothermal bainitic transformation for partitioning after thermo-mechanical control processing (online Q&P) and offline tempering (reheating and tempering). The ultrafine nanolath martensite/bainite mixed structure, combined with residual austenite in the form of a thin film between the nanolaths, was formed, thereby conferring excellent mechanical properties to the steel structures. After the Q-P-T process, the yield and tensile strengths of the steels reached 1450 MPa and 1726 MPa, respectively. Furthermore, the Brinell hardness and elongation rate were 543 HB and 11.5%, respectively, with an average impact energy of 20 J at room temperature. [ABSTRACT FROM AUTHOR]

Background: As an extension of electron tomography (ET), serial section electron tomography (serial section ET) aims to align the tomographic images of multiple thick tissue sections together, to break through the volume limitation of the single section and preserve the sub-nanoscale voxel size. It could be applied to reconstruct the intact synapse, which expands about one micrometer and contains nanoscale vesicles. However, there are several drawbacks of the existing serial section ET methods. First, locating and imaging regions of interest (ROIs) in serial sections during the shooting process is time-consuming. Second, the alignment of ET volumes is difficult due to the missing information caused by section cutting and imaging. Here we report a workflow to simplify the acquisition of ROIs in serial sections, automatically align the volume of serial section ET, and semi-automatically reconstruct the target synaptic structure. Results: We propose an intelligent workflow to reconstruct the intact synapse with sub-nanometer voxel size. Our workflow includes rapid localization of ROIs in serial sections, automatic alignment, restoration, assembly of serial ET volumes, and semi-automatic target structure segmentation. For the localization and acquisition of ROIs in serial sections, we use affine transformations to calculate their approximate position based on their relative location in orderly placed sections. For the alignment of consecutive ET volumes with significantly distinct appearances, we use multi-scale image feature matching and the elastic with belief propagation (BP-Elastic) algorithm to align them from coarse to fine. For the restoration of the missing information in ET, we first estimate the number of lost images based on the pixel changes of adjacent volumes after alignment. Then, we present a missing information generation network that is appropriate for small-sample of ET volume using pre-training interpolation network and distillation learning. And we use it to generate the missing information to achieve the whole volume reconstruction. For the reconstruction of synaptic ultrastructures, we use a 3D neural network to obtain them quickly. In summary, our workflow can quickly locate and acquire ROIs in serial sections, automatically align, restore, assemble serial sections, and obtain the complete segmentation result of the target structure with minimal manual manipulation. Multiple intact synapses in wild-type rat were reconstructed at a voxel size of 0.664 nm/voxel to demonstrate the effectiveness of our workflow. Conclusions: Our workflow contributes to obtaining intact synaptic structures at the sub-nanometer scale through serial section ET, which contains rapid ROI locating, automatic alignment, volume reconstruction, and semi-automatic synapse reconstruction. We have open-sourced the relevant code in our workflow, so it is easy to apply it to other labs and obtain complete 3D ultrastructures which size is similar to intact synapses with sub-nanometer voxel size. [ABSTRACT FROM AUTHOR]

High‐quality friction and wear resistances are very important for epoxy resin (EP) when serving as construction and coating materials. Herein, in this study, a series of nickel phyllosilicate (NiPS) nanoflowers filled EP were fabricated, and then their mechanical responses, hydrophilicity and tribological properties under wet sliding were examined thoroughly. Results showed that the compressive strength of as‐prepared nanocomposites increased first and then decreased, achieving a maximum value of 280.05 MPa at 5% filler, while the elastic modulus, hardness and hydrophilicity were all improved monotonously with elevated filler content. The presence of NiPS nanoflowers enhanced the wet‐lubricated tribological properties considerably. Both the average friction coefficient and wear rate presented similar anti‐parabolic change trends with the lowest values of 0.166 and 0.82 × 10−6 mm3/Nm obtained at 5% and 3%, which were 25.6% and 20.9% lower than pure EP, respectively. Further investigations confirmed that a relatively high applied load and sliding speed also promoted improved water‐lubricated tribological properties, suggesting a giant potential for the resulting EP nanocomposites to work safely as instrumental components under harsh conditions. [ABSTRACT FROM AUTHOR]

• Five characteristic time scales for the two-stage ignition process were defined. • The high-temperature ignition delay time varies non-linearly with the nozzle diameter (D noz). • The reduction of nozzle diameter facilitates the physical preparation process. • The variation of scalar dissipation rate with D noz provides a trade-off effect on the chemical preparation process. • The selection strategy of optimal nozzle diameter will improve the environmental adaptability of diesel engines. Diesel engine cold-start performances are closely related to ignition delay time which in turn is strongly influenced by the nozzle diameter (D noz). In this study, ignition delay time and ignition location of No. −50 diesel spray at different D noz are investigated by high-speed direct photography in a constant volume combustion chamber (CVCC) under cold-start conditions. The experimental results clarify the non-monotonic variation of the high-temperature ignition delay time (τ HTI) with decreasing nozzle diameter. The minimum experimental high-temperature ignition delay time of about 1.85 ms is obtained when D noz = 160 μm. To investigate the mechanism that the influence of nozzle diameter on high-temperature ignition delay time, numerical simulations of the n -heptane spray ignition process are performed under the same conditions as optical diagnostics. Five characteristic time scales for the two-stage ignition process are defined as: physical preparation time (τ phy), low-temperature pre-reaction time (Δ τ 1), low-temperature ignition delay time (τ LTI), high-temperature pre-reaction time (Δ τ 2), and high-temperature ignition delay time. The physical preparation time decreases linearly with nozzle diameter caused by better spray atomization, evaporation, and air-fuel mixing. Changes in nozzle diameter barely affect low-temperature pre-reaction time, indicating that the linear shortening of low-temperature ignition delay time is attributed to the acceleration of the physical preparation process. The high-temperature pre-reaction time initially decreases and then increases with decreasing D noz , which is the result of a smaller scalar dissipation rate promoting the decomposition of H 2 O 2 and inhibiting flame propagation. The combined effect of decreasing D noz at each stage leads to a non-monotonic trend in high-temperature ignition delay time. [ABSTRACT FROM AUTHOR]

In order to find a green and safe solution as the base solution for the quantitative detection of glucose, the neutral solution Na2S2O3 was selected as the base solution. A three-electrode electrochemical system was designed. In this system, the working electrode was copper sheet, the counter electrode was platinum electrode, and the reference electrode was saturated KCl calomel solution electrode. Cyclic voltammetry (CV) and chronoamperometry(i-t) methods were used for the experiment. CV scanning results showed that glucose could produce the oxidation-reduction reaction on the surface of the copper electrode, and the parameters of i-t were adjusted. According to the results of i-t scanning, the quantitative detection model of glucose was established. The model was $x = {e^{\left [{{ - \sqrt {0.3305} * \ln {{\left({y - 0.1039} \right) * \sqrt {2\pi } * 0.4065} \over {8.3459 * {{10}^{ - 4}}}} + \ln 7.3672 * {{10}^{ - 4}}} \over {1 + \sqrt {0.3305} }}\right ]}}$ x = e − 0.3305 ∗ ln y − 0.1039 ∗ 2 π ∗ 0.4065 8.3459 ∗ 10 − 4 + ln 7.3672 ∗ 10 − 4 1 + 0.3305 . The regression parameter R2 was 0.99672. Glucose was tested with different base solutions. Results showed that Na2S2O3 solution was a good base solution. The i-t control experiments showed that the proposed method were effective in Na2S2O3 solution. [ABSTRACT FROM AUTHOR]

Banana peel powder (BPP) was used to prepare poly(lactic acid) (PLA) bio-based composites and the flame retardancy was enhanced by introducing silica-gel microencapsulated ammonium polyphosphate (MCAPP). The results showed that the limiting oxygen index (LOI) of PLA containing 15 wt % BPP was 22.1% and just passed the UL-94 V-2 rate. Moreover, with the introduction of 5 wt % MCAPP and 15 wt % BPP, the PLA composite had a higher LOI value of 31.5%, and reached the UL-94 V-0 rating, with self-extinguishing and anti-dripping abilities. The PLA/M5B15 also had a lower peak heat release rate (296.7 kW·m−2), which was 16% lower than that of the PLA/B15 composite. Furthermore, the synergistic effects between MCAPP and BPP impart better thermal stability to PLA composites. According to the investigation of the char residue and pyrolysis gaseous products, MCAPP with BPP addition is beneficial to the formation of a higher quality char layer in the solid phase but also plays the flame retardant effect in the gas phase. This work provides a simple and efficient method to solve the high cost and flammability issues of PLA composites. [ABSTRACT FROM AUTHOR]

Continuous cropping obstacles poses significant challenges for melon cultivation, with autotoxicity being a primary inducer. Suberization of cells or tissues is a vital mechanism for plant stress response. Our study aimed to elucidate the potential mechanism of root suberization in melon's response to autotoxicity. Cinnamic acid was used to simulate autotoxicity. Results showed that autotoxicity worsened the root morphology and activity of seedlings. Significant reductions were observed in root length, diameter, surface area, volume and fork number compared to the control in the later stage of treatment, with a decrease ranging from 20% to 50%. The decrease in root activity ranged from 16.74% to 29.31%. Root suberization intensified, and peripheral suberin deposition became more prominent. Autotoxicity inhibited phenylalanineammonia-lyase activity, the decrease was 50% at 16 h. The effect of autotoxicity on cinnamylalcohol dehydrogenase and cinnamate 4-hydroxylase activity showed an initial increase followed by inhibition, resulting in reductions of 34.23% and 44.84% at 24 h, respectively. The peroxidase activity only significantly increased at 24 h, with an increase of 372%. Sixty-three differentially expressed genes (DEGs) associated with root suberization were identified, with KCS , HCT , and CYP family showing the highest gene abundance. GO annotated DEGs into nine categories, mainly related to binding and catalytic activity. DEGs were enriched in 27 KEGG pathways, particularly those involved in keratin, corkene, and wax biosynthesis. Seven proteins, including C4H, were centrally positioned within the protein interaction network. These findings provide insights for improving stress resistance in melons and breeding stress-tolerant varieties. • Autotoxicity worsened root morphology and vitality. • Autotoxicity increased the lignin content and suberization degree of roots. • Autotoxicity inhibited PAL and POD activities. • Autotoxicity induced C4H and CAD activity first increased and then decreased. • C4H , 4CL, LACS , ACE and CER1 are key genes related root suberization. [ABSTRACT FROM AUTHOR]

Pumpkin polysaccharide (PPe-H) can perform physiological functions through its antioxidative and hypoglycemic effects; however, the mechanisms through which PPe-H regulates abnormal glucose and lipid metabolism caused by oxidative stress injury remain unclear. In the present study, streptozotocin was used to generate an acute diabetic mouse model, and the effects of PPe-H on glucose and lipid metabolism impaired by oxidative stress in diabetic mice were studied. PPe-H significantly reduced blood glucose levels and enhanced the oral glucose tolerance of diabetic mice under stress injury (p < 0.05). The analysis of liver antioxidant enzymes showed that PPe-H significantly enhanced the activities of SOD and CAT (p < 0.05), increased the GSH level, and decreased the level of MDA (p < 0.05). Transcriptomic and metabolomic analyses of the liver tissues of mice revealed characteristic differences in the genetic and metabolic levels of the samples, which showed that PPe-H treatment may play a positive role in regulating the metabolism of methionine, cysteine, glycerol phospholipid, and linoleic acid. These results indicated that PPe-H alleviated the symptoms of hyperglycemia by regulating metabolites related to oxidative stress and glycolipid metabolism in diabetic mice. [ABSTRACT FROM AUTHOR]

Jianpiyiqi formula is a Traditional Chinese Medicine (TCM) prescription and is used for the clinical treatment of patients with chronic atrophic gastritis (CAG). The aim of the present study was to examine the underlying mechanisms of Jianpiyiqi formula treatment for CAG via the Wnt/β-catenin signaling pathway. The high-performance liquid chromatography (HPLC) chromatogram of Jianpiyiqi formula was constructed. A CAG rat model induced by N-methyl-N'-nitro-N-nitrosoguanidine and ranitidine was established. The body weight and food intake of the rats was recorded and rat gastric morphology was visually examined. Pathological analysis of rat gastric tissue was also performed. The levels of gastrin (GAS), pepsin (PP), somatostatin (SS) and prostaglandin E2 (PGE2) in rat serum were detected using ELISAs. The expression levels of proteins and genes associated with the Wnt/β-catenin signaling pathway were measured via immunohistochemistry and reverse transcription-quantitative PCR. The HPLC chromatogram of Jianpiyiqi formula was determined and as active components, liquiritin and hesperidin were identified from the chromatogram. Compared with the blank group, the body weight and feed intake of the rats were decreased, and gastric mucosal atrophy and inflammation appeared in the model group. Treatment with Jianpiyiqi formula increased the body weight and feed intake of the rats, as well as relieved the gastric atrophy and inflammation. The contents of GAS, PP, SS and PGE2 were significantly reduced in the model group compared with the blank group. Jianpiyiqi formula significantly increased GAS, PP, SS and PGE2 levels in serum of rats with CAG. In the model group, Wnt1, β-catenin and cyclin D1 protein expression levels were increased, and glycogen synthase kinase-3β (GSK-3β) protein expression levels were decreased. Jianpiyiqi formula decreased the protein expression levels of Wnt1, β-catenin and cyclin D1 and increased the protein expression levels of GSK-3β. Compared with the blank group, the mRNA expression levels of Wnt1, Wnt5a, β-catenin, cyclin D1 and MMP7 were upregulated, and the mRNA expression levels of GSK-3β were downregulated in the model group. Treatment with Jianpiyiqi formula downregulated the mRNA expression levels of Wnt1, Wnt5a, β-catenin, cyclin D1 and MMP7 and upregulated the mRNA expression levels of GSK-3β. All of the experimental results indicated that Jianpiyiqi formula exerted a therapeutic effect on rats with CAG and inhibited the activation of the Wnt/β-catenin signaling pathway. Thus, Jianpiyiqi formula, as an effective TCM prescription for treating patients with CAG, may be more widely used in the clinic. [ABSTRACT FROM AUTHOR]

Recently, functional applications of thermoplastic foams have received extensive attention from the research and materials communities, focusing on their various applications, key challenges, material systems designs, processing methods, and cellular structure characteristics needed for specific functional applications. This review paper starts with consideration of the microcellular foaming mechanism and basic concepts of microcellular foam processing, followed by polymer modification methods, and crucial factors that determine the performance of thermoplastic foams. Special emphasis has been placed on the synergies between foaming and reinforcements, including functional fillers and polymer blends; improvements in homogeneous, functional properties by achieving uniform cell structure and cell dispersion in polymer systems; and comparison of melt processing and solvent-based methods. Then, a wide array of advanced functional applications for foams—such as lightweight applications, heat and sound insulation, electromagnetic shielding, tissue engineering, oil spill cleanup, shape memory, and flexible materials—will be presented. In particular, the relationships between cellular structure and anticipated properties—including mechanical, barrier, dielectric, biomedical, and other properties required in advanced functional applications—will be discussed. Finally, we will outline a future perspective of lightweight and functional foams and suggest recommended future work regarding functional microcellular foams. [ABSTRACT FROM AUTHOR]

Given the serious threat of foodborne multidrug-resistant bacteria to animals and humans, finding an effective antibacterial compound has always been an important topic for scientists. Here, from the soil of Changbaishan, we have identified a bacterium that can inhibit the growth of Staphylococcus aureus. Nr genome database analysis and phylogenetic analysis showed that strain CB6 belongs to Bacillus velezensis. We found that the crude extract of strain CB6 has broad-spectrum antibacterial activity against foodborne pathogens. In addition, we showed that the crude extract loses antibacterial activity after treatment with papain. Next, strain CB6 was purified using ammonium sulfate precipitation, a Sephadex G-75 gel filtration column and high-performance liquid chromatography system (HPLC). Liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis indicated that the antibacterial compound was the protein ATP synthase subunit α (ATP-1), with a molecular weight of 55.397 KDa. Moreover, we reported the complete genome sequence of strain CB6, which is composed of a unique circular 3,963,507 bp chromosome with 3749 coding genes and a G + C content of 46.53%. The genome contained 12 gene clusters with antibacterial functions, which constituted over 20.947% of the complete genome. Of note, the amino acid sequence encoding the ATP-1 protein in the strain CB6 genome was identified. In addition to these findings, we speculate that the ATP-1 protein may provide energy for secondary metabolites, which in turn will improve the antibacterial activity of the secondary metabolites. All the above important features make the ATP-1 as a potential candidate for the development of new antibacterial drugs and food preservatives in the future. [ABSTRACT FROM AUTHOR]

The wide application of agricultural plastics leads to microplastic (MP) accumulation in the soil and inevitably result in MP pollution. Melon is an economically important horticultural crop that is widely cultivated with plastic film mulching. However, the impact of MP pollution on plant growth remains largely unclear. Here we reported the morphological, physiological, biochemical responses and transcriptome re-programing of melon responses to MP on seed germination and seedling growth. Polyvinyl chloride particles were added to potting mix to simulate MP exposure environment (MEE). The results showed that low and medium concentrations (1–4 g kg−1) of MEE had a significant adverse effect on seed germination and seedling growth. In both cases, the germination potential was decreased, young root forks increased, and tips decreased; and the dry weight of seedlings, the total length, surface area, forks and tips of root were also decreased. However, the root activity was increased. The concentration of MEE to give the best parameters was at 2 g kg−1. Catalase enzymatic activity and reactive oxygen species (ROS) in roots were decreased continuously with increased MEE concentrations. The peak values of peroxidase activity, O 2 .- content and generation rate, ROS enrichment and malondialdehyde content all reached the highest at 2 g kg−1. MEE also increased the proline content and decreased the contents of ascorbic acid, soluble sugar and soluble protein in these seedlings. Medium and high concentrations of MEE (4–8 g kg−1) also increased the chlorophyll b content. Low concentrations MEE (1–2 g kg−1) inhibited actual photochemical efficiency of photosystem II and photochemical quenching, two key chlorophyll fluorescence parameters. Transcriptome analysis showed that the differentially expressed genes caused by the MEE were mainly belonged to defense response, signal transduction, hormone metabolism, plant-pathogen interaction, and phenylpropanoid biosynthesis. The results of this study will help to understand the ecotoxicological effects of MEE on melons and provide data for ecological risk assessment of Cucurbitaceae vegetable cultivation. [ABSTRACT FROM AUTHOR]

Enrichment plants were screened from six forage grasses in this study to establish a complete combined forage grass-microbial remediation system of strontium-contaminated soil, and microbial groups were added to the screened dominant forage grasses. The occurrence states of strontium in forage grasses were explored by the BCR sequential extraction method. The results showed that the annual removal rate of Sudan grass (Sorghum sudanense (Piper) Stapf.) reached 23.05% in soil with a strontium concentration of 500 mg·kg−1. Three dominant microbial groups: E, G and H, have shown good facilitation effects in co-remediation with Sudan grass and Gaodan grass (Sorghum bicolor × sudanense), respectively. When compared to the control, the strontium accumulation of forage grasses in kg of soil with microbial groups was increased by 0.5–4 fold. The optimal forage grass-microbial combination can theoretically repair contaminated soil in three years. The microbial group E was found to promote the transfer of the exchangeable state and the reducible state of strontium to the overground part of the forage grass. Metagenomic sequencing results showed that the addition of microbial groups increased Bacillus spp. in rhizosphere soil, enhanced the disease resistance and tolerance of forage grasses, and improved the remediation ability of forage grass-microbial combinations. [Display omitted] • The addition of exogenous microbial group enhances the ability of strontium enrichment in forage grass. • The inoculation of the microbial group promotes strontium transfer to the overground part of forage grass. • Exogenous microbial group changes the occurrence states and storage sites of strontium in forage grass. • Exogenous microbial group alters the abundance, structure and function of the microbial community in rhizosphere soil. • The inoculation of the microbial group enhances disease resistance and tolerance of forage grass. [ABSTRACT FROM AUTHOR]

In this study, the two-dimensional bimetallic nanosheets, M(OH)(OCH 3) (M = Co, Ni) was used as a novel "nano-flame retardant" to improving fire retardancy and smoke suppression of epoxy resin (EP) nanocomposties. With 3 wt% M(OH)(OCH 3) added, the peak heat release of EP/M(OH)(OCH 3)-3 wt% decreased from 1021.4 to 867.8 kW/m2, compared with pure EP. To the smoke suppression, the peak of smoke product rate and the total smoke product of EP/M(OH)(OCH 3)-3 wt% was 0.27 m2/s and 28.3 m2, which decreases by 15.6 and 15.0% than those of pure EP, respectively. Only 1 wt% M(OH)(OCH 3)@Ni, which got the modification by the introduction of nickel ion on surface, could endow the composite a further improvement in both flame retardant and smoke suppression. The results of gas chromatography-mass spectrometer demonstrated the M(OH)(OCH 3)@Ni facilitated the aromatization reaction and promotes the generation of the protective char layer, which hinders the propagation of combustible free radicals and restrains the release of smoke. This study demonstrated that the two-dimensional bimetallic nanosheets, M(OH)(OCH 3) (M = Co, Ni), has a great potential to act as novel "nano flame retardant". Moreover, the appropriate modification could further promote its performance in improving the flame ratardancy and smoke suppression of EP. • M(OH)(OCH 3)(M = Co, Ni) was used as a novel "nano-flame retardant" to fabricate flame retardant and smoke suppression EP. • 3 wt% M(OH)(OCH 3) could efficiently enhance the flame retardant and smoke suppression of EP composites. • 1 wt% M(OH)(OCH 3)@Ni realize a further promotion in flame retardant and smoke suppression of EP. • Aromatization reaction has been confirmed as the effective mechanism of flame retardant and smoke suppression. [ABSTRACT FROM AUTHOR]

The formation and development of tight oil reservoirs in the fourth member of the Shahejie Formation (Es 4) in the Leijia region of the western sag of the Liaohe Depression are highly heterogeneous and influenced by several factors. The relationship between these variables is extremely complex. In order to avoid deviations caused by single factors and logging data for less drilling when regional tight oil reservoirs have been assessed, quantitative evaluation methods for tight reservoirs based on multi-feature fusion have been proposed. Hand-drawn maps of brittleness index, carbonate rocks thickness, fracture density, mean permeability, and mean porosity are gridded by the Kriging model accompanied by k -means clustering to determine the types of reservoir and classification interval. After that, two quantitative evaluation methods, the overlapping favourability method (OFM) and the principal component analysis (PCA), were used to analyze the five influence factors of the tight oil reservoirs. Finally, reservoir evaluation maps were generated by dividing the interval values into classes. Results show that the weights of the five variables calculated by the hybrid weight method (HWM) are 0.1100,0.4929, 0.0803, 0.2889, and 0.0279. The reservoirs in the study area are finally divided into four types, with the best reservoir types primarily distributed in well areas, such as A99, A82, A91, A78, and A9. At the same time, the main controlling factors for the creation of the reservoir have been analyzed; however, the thickness of carbonate rock in the study area plays a decisive role in the development of high-quality reservoirs. The brittleness index and fracture density can significantly improve the efficiency of the reservoir. Quantitative approaches can effectively and scientifically evaluate the tight reservoirs, which can be widely used. • The k-means clustering was used to classify the data gridded by the Kriging model, to decide the types of reservoirs and classification interval values. • Two quantitative evaluation methods, i.e. the overlapping favourability method (OFM) and the principle component analysis (PCA), were used to analyze and merge different features for the assessment of reservoirs. • The assessment results of these quantitative approaches are straightforward and easy to view, providing a reliable geological foundation for further in-depth exploration and application of oilfields. [ABSTRACT FROM AUTHOR]

• Acetaldehyde and formaldehyde are the dominant intermediate products of ethanol and DME. • The inhibition of methyl on laminar burning velocity is weaker than the enhancement of H and OH radicals. • The S L of DME and ethanol correlates linearly with the peak mole fraction of H + OH + CH 3. • The hydrodynamic and diffusional-thermal instability of DME are all stronger than ethanol. Ethanol and DME are the most promising gasoline and diesel alternative fuels among biofuels. In the present study, we conducted a numerical and comparative study of the laminar burning velocity, chemical kinetics and flame instability of DME and ethanol premixed flames at P = 1 bar, T = 408 K and equivalence ratio of 0.8–1.4. The laminar burning velocity and adiabatic flame temperature of DME are higher than ethanol at all equivalence ratios. In addition, acetaldehyde and formaldehyde are the dominant intermediate product of ethanol and DME, respectively. The peak mole fraction of H + OH + CH 3 radicals correlates nearly linearly with the laminar burning velocity. The rate-of-production of DME and ethanol suggests that CH 3 + O = CH 2 O + H is the main reaction of CH 3 consumption in both DME and ethanol flames. In addition, the reverse reaction of CH 3 + O = CH 2 O + H is enhanced to inhibit the consumption of CH 3 due to the high mole fraction of CH 2 O in DME, which is one of the reasons that the mole fraction of CH 3 in DME flame is higher than in ethanol flame. Furthermore, the hydrodynamic and diffusional-thermal instability of DME are both stronger than ethanol because of thinner flame thickness, higher thermal expansion ratio and smaller effective Lewis number. [ABSTRACT FROM AUTHOR]

• The increases of laminar burning velocity of TRF-H2-air mainly due to the increase of H and OH radicals. • The dilution/thermal and chemical effect of hydrogen is as follow: Chemical > dilution > thermal. • The dilution/thermal effect on CO 2 and CO's mole fraction is the dominant effect. • The correlation between the S L and the sum of H + OH + O is as followed: S L = 104X [H+OH+O] − 1.7235. Because of its high reactivity, rapid flame speed, and low ignition energy, hydrogen is an excellent additive in gasoline to improve the combustion performance and reduce pollutant formation. In this study, we conducted a numerical study of the effect of hydrogen blending into TRF (toluene/iso-octane/n-heptane)/air mixtures on laminar burning velocity and flame structure at the initial pressure of 1 bar, initial temperature of 453 K, equivalence ratio of 0.8–1.4 and hydrogen addition ratio range from 0% to 50%. The adiabatic flame temperature increases slightly and the thermal diffusion coefficient increases significantly with hydrogen addition. The peak values of H + OH + O mole fractions are correlated nearly linearly with the laminar burning velocity, indicating a direct correlation relationship between the peak mole fraction of H + OH + O and the laminar burning velocity. The increase of reaction rate of R361 (H + O 2 = O + OH) is one of the main reasons for the enhanced laminar burning velocity due to hydrogen addition. The rate-of-production analysis of fuel shows that hydrogen promotes the consumption of hydrocarbons. The thermal/dilution and chemical effects of hydrogen addition were numerically quantified. The chemical effect is the dominant effect on laminar burning velocity. In the last part of the study, we separated the thermal, chemical and dilution effects of hydrogen addition and the results demonstrate that the relative importance of these effects follow the order of chemical > dilution > thermal under the conditions of our study. [ABSTRACT FROM AUTHOR]

• Composites with sandwiched structure of CuTi/Gr/CuTi were prepared. • After Ti doping, Cu/Gr interface bonding was increased by 230.7%. • The interfacial TiC acts as binder and second phase and Ti refines Cu grains. Layered composites with sandwiched structure of copper-titanium/graphene/copper-titanium (CuTi/Gr/CuTi) are designed and synthesized to elucidate the effects of Ti on the Cu/Gr interfacial strength. Compared with the composites without Ti alloying, the as-prepared CuTi/Gr/CuTi exhibits significantly increased interfacial tensile strength from 29.3 ± 8.4 MPa up to 67.6 ± 11.1 MPa. Microstructure examination shows the formation of a large amount of TiC nanoparticles on the Cu/Gr interface, which not only act as second phase to strengthening the interface, but also serve as binder between Cu and Gr to improve the interfacial bonding. In addition, Ti refines the grains of Cu matrix, which is beneficial to enhance the Cu/Gr interfacial strength in the layered composites. [ABSTRACT FROM AUTHOR]