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The poor conductivity, poor stability, and agglomeration of iron-based metal organic framework MIL-88A(Fe) limit its application as persulfate (PS) activator in water purification. Herein, MXene-supported MIL-88A(Fe) composites (M88A/MX) were synthesized to enhance its adsorption and catalytic capability for tetracycline (TC) removal. Scanning electron microscope (SEM), X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR), and X-ray photoelectron spectroscopy (XPS) were used to characterize prepared materials, confirming the successful attachment of MIL-88A(Fe) to the surface of MXene. M88A/MX-0.2 composites, prepared with 0.2 g MXene addition, exhibit optimal degradation efficiency, reaching 98% under conditions of 0.2 g/L M88A/MX-0.2, 1.0 mM PS, 20 ppm TC, and pH 5. The degradation rate constants of M88A/MX-0.2 were 0.03217 min−1, which was much higher than that of MIL-88A(Fe) (0.00159 min−1) and MXene (0.00626 min−1). The removal effects of reaction parameters, such as dosage of M88A/MX-0.2 and PS; initial solution pH; and the presence of the common co-existing constituents (humic acid and the inorganic anions) were investigated in detail. Additionally, the reuse of M88A/MX-0.2 showed that the composites had good cycling stability by recurrent experiments. The results of electron paramagnetic resonance (EPR) and quenching experiments indicated that ·OH, ·SO4−, and ·O2− were involved in the M88A/MX-0.2/PS system where persulfate oxidation process was activated with prepared M88A/MX-0.2. In addition, the intermediates of photocatalytic degradation were determined by HPLC–MS, and the possible degradation pathways of the target molecules were inferred. This study offered a new avenue for sulfate-based degradation of Fe-based metal organic framework. [ABSTRACT FROM AUTHOR]

When transforming from a traditional rural economy to a rapid marketization period, it is essential to consider the relationship between multiple shocks and household income in poor rural areas of China. Using two waves of a rural household surveys from six poor counties in China between 2015 and 2018, we examine the effect of multiple shocks on households' income and explore the heterogeneity of different shocks and households based on income. The multiple linear regression and quantile regression results demonstrate that multiple shocks negatively affect farm household income, and the range of impact is widening. Specifically, natural disaster shocks reduce the income of low-income households more, and unnatural disaster shocks reduce the income of middle–low-income farm households more. We conclude that illness within the family and lack of working household members are the primary shocks currently suffered by different types of farm households. In contrast to previous research, this study identifies middle–low-income farm households as most in need of attention and reveals that unnatural disaster shocks in poor rural areas of China are most in need of governance during recovery transitions. The findings enrich the existing theoretical system and provide policymakers with practical insights regarding differentiated and preemptive risk governance approaches. [ABSTRACT FROM AUTHOR]

Extreme weather events are among the main channels through which natural disaster shocks interact with poverty. Microlevel research regarding the effects of government support on poor rural households' resilience to natural disasters is beneficial for identifying complementarities between disaster mitigation and poverty alleviation. In contrast to previous research, this study directly explores the impact of government support on households' ability to resist natural disaster shocks in China in the context of multiple natural disasters. Using four waves of a rural household panel survey in six poor counties in China, this study applies PSM-DID and mediating effect models to explore the impact of government support on households' ability to resist natural disaster shocks. Four relevant emerge. (1) Government support could significantly reduce the probability of households suffering from natural disaster shocks and improve households' ability to resist natural disaster shocks. (2) Government support can increase households' ability to resist natural disaster shocks by raising non-farm income. (3) Government support primarily enhances resistance to natural disasters among poor and small rural households. (4) Government support has more significant effects in reducing the probability of households suffering from droughts and floods. We argue that government provision of targeted safety net programs to mitigate the effects of systemic natural hazards is crucial for establishing risk resilience for farm households, and the conditions for policy effectiveness must be addressed. [ABSTRACT FROM AUTHOR]

Background: Volatile organic compounds (VOCs) are a broad class of chemicals, and previous studies showed that VOCs could increase the risk of central nervous system disorders. However, few studies have comprehensively explored their association with depression among general adults. Objective: We aimed to explore the association between blood VOCs and depression risk based on a large cross-sectional study of the National Health and Nutrition Examination Survey (NHANES). Methods: We analyzed data from 3449 American adults in the NHANES 2013–2016. Survey-weighted logistic regression model was used to explore the association of ten blood VOCs with depression. Subsequently, the relative importance of the selected VOCs was determined using the XGBoost model. The weighted quantile sum (WQS) regression model was used to explore the overall association of 10 blood VOCs with depression. Subgroup analyses were performed to identify high-risk populations. Finally, restricted cubic spline (RCS) analysis was utilized to explore the dose–response relationship between blood VOCs and the risk of depression. Results: XGBoost Algorithm model identified blood 2,5-dimethylfuran was the most critical variable in depression. The logistic regression model showed that blood benzene, blood 2,5-dimethylfuran, and blood furan showed a positive correlation with depression. In subgroup analysis, we found that the effects of the above VOCs on depression existed among the female, young middle-aged, and overweight-obese population. Mixture VOCs exposure was positively associated with depression risk (OR = 2.089, 95% CI: 1.299–3.361), and 2,5-dimethylfuran had the largest weights in WQS regression. RCS displayed that blood benzene, blood 2,5-dimethylfuran, and blood furan were positively associated with depression. Conclusion: The results of this study indicated that VOCs exposure was associated with an increased prevalence of depression in U.S. adults. Women, young and middle-aged, and overweight-obese populations are more vulnerable to VOCs. [ABSTRACT FROM AUTHOR]

Magnetic susceptibility (MS) technology can achieve the efficient rough measurement, mapping, and pollution assessment of soil heavy metal concentrations in topsoil due to atmospheric dust contamination. However, previous studies of commonly used MS field probes (MS2D, MS2F, and MS2K) have not dealt with the range of magnetic signal detection and the attenuation characteristics of the signal with respect to distance. In this study, the vertical and horizontal measurement ranges of the MS2D, MS2F, and MS2K probes were explored through laboratory and field experiments, and the intensity of their magnetic signals was further compared and analyzed in the field. The results showed that the magnetic signal intensity of the three probes decreased exponentially with distance. The penetration depths of the MS2D, MS2F, and MS2K probes were 8.5, 2.4, and 3.0 cm, respectively, and the horizontal detection boundary lengths of their magnetic signals were 32, 8, and 6.8 cm, respectively. In the field surface soil MS detection, the magnetic measurement signals of the MS2F and MS2K probes showed a weak linear correlation with the MS2D probe (R2 of 0.43 and 0.50, respectively), while the MS2F and MS2K probes had a significantly better correlation (R2 = 0.68) with each other. In general, the MS2D probe and MS2K probe correlation had a slope close to unity, meaning MS2K probes had good mutual substitution. Furthermore, results of this study improve the effectiveness of the MS evaluation of heavy metal pollution in urban topsoil. [ABSTRACT FROM AUTHOR]

Porous polymer (pyrrolopyrrole) was successfully prepared via domino-ring-formation reaction. The chemical-physical properties of cyanided covalent triazine frameworks (CTF-CN) were characteriazed by fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), specific surface area analyzer (BET) and thermogravimetric analysis (TGA), respectively. The experimental results of adsorption of chloranil (TCBQ) in aqueous solution indicated that CTF-CN exhibited distinctive adsorption capacity toward TCBQ owing to its large specific surface area. Specifically, the adsorption equilibrium of as-prepared polymer was executed within 5 h and the calculated adsorption capacity was 499.76 mg/g. Furthermore, the adsorption kinetics could be well defined with the linear pseudo-second-order model, which implies that the chemical interaction are relative important in the course of TCBQ removal. Finally, the current studies verify that CTF-CN has unique rigid and nano-porous framework structure, which can be employed for the treatment of a series of harmful aromatic substances. [ABSTRACT FROM AUTHOR]

Bone grinding is an essential and vital procedure in most surgical operations. Currently, the insufficient cooling capacity of dry grinding, poor visibility of drip irrigation surgery area, and large grinding force leading to high grinding temperature are the technical bottlenecks of micro-grinding. A new micro-grinding process called ultrasonic vibration-assisted nanoparticle jet mist cooling (U-NJMC) is innovatively proposed to solve the technical problem. It combines the advantages of ultrasonic vibration (UV) and nanoparticle jet mist cooling (NJMC). Notwithstanding, the combined effect of multi parameter collaborative of U-NJMC on cooling has not been investigated. The grinding force, friction coefficient, specific grinding energy, and grinding temperature under dry, drip irrigation, UV, minimum quantity lubrication (MQL), NJMC, and U-NJMC micro-grinding were compared and analyzed. Results showed that the minimum normal grinding force and tangential grinding force of U-NJMC micro-grinding were 1.39 and 0.32 N, which were 75.1% and 82.9% less than those in dry grinding, respectively. The minimum friction coefficient and specific grinding energy were achieved using U-NJMC. Compared with dry, drip, UV, MQL, and NJMC grinding, the friction coefficient of U-NJMC was decreased by 31.3%, 17.0%, 19.0%, 9.8%, and 12.5%, respectively, and the specific grinding energy was decreased by 83.0%, 72.7%, 77.8%, 52.3%, and 64.7%, respectively. Compared with UV or NJMC alone, the grinding temperature of U-NJMC was decreased by 33.5% and 10.0%, respectively. These results showed that U-NJMC provides a novel approach for clinical surgical micro-grinding of biological bone. [ABSTRACT FROM AUTHOR]

As a tumor suppressor in lung cancer, FAT atypical cadherin 4 (FAT4) has a critical role in epithelial-mesenchymal transition (EMT). However, the role of FAT4 in ceritinib-resistant anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer (NSCLC) EMT has not been reported. It is necessary to discuss the role of FAT4 in this process and its potential mechanism of interaction. We found that the expression level of FAT4 was downregulated markedly in ceritinib-resistant NCI-H2228 (H2228/Cer) cells. Jujuboside A, a FAT4 activator, diminished EMT and metastasis of H2228/Cer cells. Importantly, autophagy inhibition inverted the inhibitory effect of FAT4 activation on EMT. Furthermore, we found the regulatory action of FAT4 on autophagy was related to proteasome 26S subunit ubiquitin receptor and non-ATPase 4 (PSMD4) and proteasome 20S subunit beta 4 (PSMB4), and the inhibitory effect of autophagy on EMT might be related to ROS/NF-κB/IκB-α and Wnt/β-catenin pathways. In conclusion, FAT4 activation can inhibit the process of EMT in H2228/Cer cells by promoting autophagy, which provides a potential target for ceritinib-resistant ALK positive NSCLC therapy. [ABSTRACT FROM AUTHOR]

A series of ZnO/ZrO2 catalysts were prepared by atomic layer deposition (ALD) and impregnation method and were test for CO2 hydrogenation to methanol. The results showed that ZnO deposited by the ALD method was highly dispersed on ZrO2, while the catalysts prepared by impregnation method formed ZnO–ZrO2 solid solution. Due to the formation of solid solution, a strong interaction between the Zn–Zr–O can be detected from XPS measurements for the impregnated sample. For ZnO/ZrO2 catalysts, the solid solution played an important role in the catalytic performance. The catalysts prepared by ALD did not form the solid solution; therefore, they were inferior to the sample prepared by impregnation method. [ABSTRACT FROM AUTHOR]

The main danger of cold stress to animals in cold regions is systemic metabolic changes and protein synthesis inhibition. RBM3, an exceptional cold shock protein, is rapidly upregulated in response to hypothermia to resist the adverse effects of cold stress. However, the mechanism of the protective effect and the rapid upregulation of RBM3 remains unclear. O-GlcNAcylation, an atypical O-glycosylation, is precisely regulated only by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) and participates in the signal transduction of multiple cellular stress responses as a "stress and nutrition receptor." Therefore, our study aimed to explore the mechanism of RBM3 regulating glucose metabolism and promoting survival in skeletal muscle under acute cold exposure. Meanwhile, our study verifies whether O-GlcNAcylation mediated by OGT rapidly upregulates RBM3. The blood and skeletal muscle of mice were collected at the end of cold exposure treatment for 0, 2, and 4 h. Changes in levels of RBM3, AKT, glycolysis apoptosis, and OGT were measured. The results show that acute cold exposure upregulated RBM3, OGT, and AKT phosphorylation and increased energy consumption, which enhanced glycolysis and prevent apoptosis. In the 32 °C mild hypothermia model in vitro, overexpression of RBM3 enhanced AKT phosphorylation. Meanwhile, inactivation of AKT by wortmannin resulted in increased apoptosis and decreased glucose metabolism in skeletal muscle under acute cold exposure. In addition, OGT-mediated O-GlcNAcylation of p65 was confirmed in mouse myoblast cell line (C2C12) cells at mild hypothermia. O-GlcNAcylation level affected p65 activity and nuclear translocation. Compared with wild type (WT) mice, RBM3 and p65 phosphorylation were decreased in specific skeletal muscle Ogt (KO) mice, whereas AKT phosphorylation, glycolysis, and apoptosis were increased. Taken together, O-GlcNAcylation of p65 upregulates RBM3 to promote AKT phosphorylation, enhance glucose metabolism, and reduce apoptosis in skeletal muscle of mice under acute cold exposure. [ABSTRACT FROM AUTHOR]

Avian leukosis, caused by avian leukosis virus (ALV), is an infectious tumor disease and severely hinders the development of the poultry industry. The use of Lactobacillus plantarum (L. plantarum) could effectively alleviate viremia in the early period of J subgroup ALV (ALV-J) infection. In this study, an invasive L. plantarum NC8 expressing Gp85 protein of ALV-J was constructed. After chickens were orally administered the recombinant invasive NC8, the levels of expression of CD4+ and CD8+ T lymphocytes in peripheral blood and spleen by flow cytometry and the proliferation ability of splenocytes by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay were examined, and the contents of cytokines, the anti-ALV-J antibody in serum, and mucosal antibody sIgA in intestinal lavage fluid were detected by enzyme-linked immunosorbent assay (ELISA). The immunoprotective efficiency was evaluated by monitoring the infection rate, the percent of cloacal swabs and survival, body weight gain, the organ indexes, and relative virus loads after challenge with ALV-J. The results showed that the recombinant invasive strain (FnBPA-gp85) could promote the expression levels of the CD8+T cells in peripheral blood and spleen, the proliferation of splenocytes, the secretions of cytokines interleukin 2 (IL-2) and γ-interferon (IFN-γ), and the production of IgG and sIgA compared with the PBS and FnBPA control groups in chickens. The FnBPA-gp85 group was exhibited the highest immune protection against ALV-J infection. The above results indicated that the recombinant invasive NC8 could promote the cellular immunity, humoral immunity, and mucosal immunity responses in chicken and provide a new method for exploring the live vaccine against ALV-J. Key points • The FnBPA-gp85 strain could enhance cellular immunity response. • The FnBPA-gp85 strain could improve the immune protection against ALV-J infection. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) is considered as the bottleneck of electrochemical water splitting because of its sluggish kinetics. Therefore, the design and synthesis of highly active, low-cost, and stable electrocatalysts for the OER is the greatest challenge in electrochemical water splitting. Here, an amorphous heterogeneous NiFe-LDH@Co(OH)2@NF with abundant active sites is fabricated by a step-wise electrodeposition technique. Firstly, Co(OH)2 is directly deposited onto nickel foam (NF) substrate by a electrodeposition technique. Secondly, NiFe-layered double hydroxide (NiFe-LDH) is further covered on the surface of Co(OH)2 to obtain the heterogeneous NiFe-LDH@Co(OH)2@NF electrocatalyst. The thickness of NiFe-LDH can be controlled by changing the time of electrochemical deposition. Benefiting from the amorphous structure and the positive synergies between NiFe-LDH and Co(OH)2, the optimized NiFe-LDH@Co(OH)2@NF-300 shows high electro-catalysis activity. In the 1 M KOH solution, the overpotential for OER is only 130 mV (at 10 mA cm−2). Remarkably, serving as a bifunctional electrode in alkaline electrolyzer, it only needs 1.6 V to reach the current density of 10 mA cm−2. The work provides a simple and viable technical solution for fabricating non-noble electrocatalysts with excellent performance for electrochemical water splitting. [ABSTRACT FROM AUTHOR]

The organic magnetoelectric complexes are beneficial for the development on flexible magnetoelectric devices in the future. In this work, we fabricated all organic multiferroic ferromagnetic/ferroelectric complexes to study magnetoelectric coupling at room temperature. Under the stimulus of external magnetic field, the localization of charge inside organic ferromagnets will be enhanced to affect spin–dipole interaction at organic multiferroic interfaces, where overall ferroelectric polarization is tuned to present an organic magnetoelectric coupling. Moreover, the magnetoelectric coupling of the organic ferromagnetic/ferroelectric complex is tightly dependent on incident light intensity. Decreasing light intensity, the dominated interfacial interaction will switch from spin–dipole to dipole–dipole interaction, which leads to the magnetoelectric coefficient changing from positive to negative in organic multiferroic magnetoelectric complexes. [ABSTRACT FROM AUTHOR]

The present work investigates the influence of the laser power (P) and scanning speed (v) on the surface morphology and Vickers microhardness of single scan tracks formed by directed energy deposition (DED) to determine suitable parameter values for further in-depth investigation of additive and subtractive hybrid manufacturing (ASHM) of fabricated parts. The experimental results show that the depth and width of the melt pool depended significantly on both P and v. Furthermore, the anisotropic mechanical behavior of bulk 316L specimens fabricated by ASHM in the horizontal (H), edge (E), and vertical (V) directions relating to the build layers was also explored. The results show that the tensile strength of the specimens fabricated by ASHM in the H direction was higher than that of those built in the E or V direction, implying that the anisotropy originates from the unique thermal history of each component location owing to the layer-by-layer nature of the DED process. [ABSTRACT FROM AUTHOR]

The design and preparation of electrode materials with unique nanostructure are regarded as a significant strategy to increase the capacitance and cycling stability of energy storage devices. Herein, a starfish-like core–shell Ni(OH)2@CoS material grown on Ni foam (Ni(OH)2@CoS/NF, denoted as NOCS-1/NF) was successfully fabricated via a stepwise hydrothermal method. Benefiting from the unique starfish-like core–shell nanostructure, obvious and abundant heterogeneous interfaces, and good synergy between every component, the specific capacitance of the as-prepared Ni(OH)2@CoS-1/NF electrode can reach up to 981 F g−1 at 1 A g−1 and maintained 73.2% of initial value at a high current density of 10 A g−1 in 2 M KOH aqueous solution. Moreover, a hybrid supercapacitor was prepared by using core–shell NOCS-1/NF as positive electrode and activated carbon coated on the NF (AC/NF) as negative electrode. The HSC delivered a high energy density of 17.9 Wh kg−1 at a power density of 749 W kg−1 and a satisfying cycling life with 90.1% capacitance retention after 4000 cycles. Eventually, two such devices in series successfully illuminated a red light-emitting diode. Meanwhile, this work probably provides a simple and convenient strategy to fabricate novel materials for the applicability of various energy-related fields. [ABSTRACT FROM AUTHOR]

The serious problems of environmental pollution and energy shortage have pushed the green economy photocatalysis technology to the forefront of research. Therefore, the development of an efficient and environmentally friendly photocatalyst has become a hotpot. In this work, magnetic Fe3O4/C/MnO2/C3N4 composite as photocatalyst was synthesized by combining in situ coating with low-temperature reassembling of CN precursors. Morphology and structure characterization showed that the composite photocatalyst has a hollow core–shell flower-like structure. In the composite, the magnetic Fe3O4 core was convenient for magnetic separation and recovery. The introduction of conductive C layer could avoid recombining photo-generated electrons and holes effectively. Ultra-thin g-C3N4 layer could fully contact with coupled semiconductor. A Z-type heterojunction between g-C3N4 and flower-like MnO2 was constructed to improve photocatalytic performance. Under the simulated visible light, 15 wt% photocatalyst exhibited 94.11% degradation efficiency in 140 min for degrading methyl orange and good recyclability in the cycle experiment. [ABSTRACT FROM AUTHOR]

Based on the etching of gold nanorods (GNRs) and enzyme-linked immunosorbent assay (ELISA), a multicolor immunosensor for visual detection of enterovirus 71 infection is proposed. Once the immunocomplex is formed, the horseradish peroxidase bound to the ELISA plate oxidizes 3,3′,5,5′-tetramethylbenzidine (TMB) into TMB2+ in the presence of hydrogen peroxide. Subsequently, TMB2+ quantitatively etches GNRs to the short GNRs, leading to a blue shift of longitudinal localized surface plasmon resonance and corresponding color responses. This change is used to develop two types of cut-off standards, which respond to the human anti-enterovirus at a concentration of 71 IgM antibody. The method has been validated with clinical serum samples and showed high sensitivity and specificity. This visual immunosensor has an important application value for point-of-care detection of EV71, especially in areas lacking detection equipment. [ABSTRACT FROM AUTHOR]

In this study, Inconel 718 (IN718) superalloys were fabricated by laser additive manufacturing (LAM) under different laser power. The microstructure and precipitation phase of IN718 superalloys were examined by optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometer (EDS) methods. The results show that the micropores of the specimens decrease with the increasing laser power. Meanwhile, the morphology of Nb-rich Laves phase changed from skeleton-like to island-like, and the sizes reduced from 10 to below 2 μm. When the laser power of 1200 W is applied, the dense microstructure and the uniformly distributed Laves phase with smallest volume and quantity are observed. The dry sliding test is performed to record the coefficient of friction (CoF) and wear loss of IN718 superalloys, and then the wear surface is detected by a laser scanning confocal microscope (LSCM) and a SEM. The results indicate that the laser power played a crucial role in wear performance of the specimens. At an optimal laser power of 1200 W, a relatively stable friction state and the lowest wear rate of 1.355 × 10−3 mm3 N−1 m−1 are obtained during the wear process. Less debris and slighter plastic deformation are detected and the wear mechanism is abrasive wear and adhesive wear. [ABSTRACT FROM AUTHOR]

Enzyme-linked immunosorbent assay (ELISA), as an immunoassay platform, usually suffers from poor sensitivity due to the limited signal intensity. To overcome this obstacle, an alkaline phosphatase–triggered immunoassay based on fluorogenic reaction of o-phenylenediamine and ascorbic acid was developed for sensitive detection of chloroacetamide herbicides in corn. The new immunoassay revealed limits of detection (LODs) for acetochlor (ATC), metolachlor, and propisochlor of 1.19 ng/mL, 2.34 ng/mL, and 3.40 ng/mL, respectively. The average recoveries of the three chloroacetamide herbicides in corn sample were 88.4%, 91.8%, and 87.6%, respectively. Such fluorescent immunoassay via in situ formation of fluorescent signal from scratch provides a new strategy with excellent sensitivity in point-of-care test of chloroacetamide herbicides. [ABSTRACT FROM AUTHOR]

This review (with 126 references) summarizes the progress that has been made in the use of carbon nanotubes (CNTs) in immunoassays and immunosensors. Following an introduction into the field, a first large section covers functional group-modified CNTs as carriers for antibodies (with subsections on CNTs modified with amino, carboxy and by various other materials). The next section treats CNTs coupled with inorganic or organic materials as active components (with the use of nanoparticles such as Fe3O4, ZnO, gold) or with indium tin oxide (ITO), NiCoBP, ionic liquids, TiO2 nanosheets, metal clusters; chitosan, polystyrene, polydopamine, graphene, or enzymes. Another section discusses the synergistic effects of CNTs with metals, metal ions, and organic/inorganic materials. Several Tables are presented that give an overview on the wealth of methods and materials. A concluding section summarizes the current status, addresses current challenges, and gives an outlook on potential future trends. [ABSTRACT FROM AUTHOR]

Directed energy deposition (DED) is capable of manufacturing high-density and complex metal components, whereas traditional machining methods are limited in these regards. Nevertheless, the fabrication of parts with DED that have accurate dimensions and geometries as well as acceptable surface states is a concern, as these factors are inferior to those of traditionally machined components. Therefore, the application of parts fabricated with DED is restricted. Thus, the hybrid additive/subtractive manufacturing (HASM) method has been exploited to comprehensively utilize the advantages of both. In this paper, the HASM method was used to fabricate bulk parts with four different scanning strategies (alternating the orientation of subsequent layers by 0°, 45°, and 90° and island scanning are referred to as an X-scan, a Rot-scan, an XY-scan, and an Island-scan, respectively) followed by subtractive milling to gain a smooth surface with a determined thickness for the next scanning and deposition period until the parts were completely finished. The influence of the scanning strategy on the densification level and mechanical behavior of the specimens fabricated with HASM was studied. The results show that the specimens fabricated with the 7 × 7 mm2 island scan with short scan vector lengths showed a higher densification than the specimens fabricated using long scan vector lengths (the three methods mentioned above). Finally, to obtain a fine surface finish, the influence of the feed per tooth (fz) on the surface quality of a 316L stainless steel during the milling process that occurs during the HASM process was also investigated. The result shows a fz of 0.25 mm yielding the minimum surface roughness value among the samples observed herein, which implies that the surface quality was better than that of the other studied conditions. [ABSTRACT FROM AUTHOR]

A unique 3D bilayer nanostructure constructed with NiCo-layered double hydroxide nanosheets (NiCo LDH) has been constructed as an excellent electrode material. Herein, carbon cloth@basic cobalt carbonate nanosheet (CC@CCH NS) precursor is synthesized by simple hydrothermal method, and CC@CCH NS@NiCo LDH (CC@CCH@NC-DH) is synthesized via direct electrodeposition. The CC@CCH@NC-DH electrodes have been assessed and optimized by adjusting the feed ratio of Ni/Co in hydrothermal reaction. The SEM images show that the bilayer nanostructure of the CC@CCH@NC-DH electrode is the most obvious when the feed ratio of Ni/Co is 2:4. Electrochemical measurements confirm that the as-prepared CC@CCH@N2C4-DH electrode has high area-specific capacitance of 7.71 F cm−2 at 10 mA cm−2 and outstanding cycling stability at 35 mA cm−2. Superior rate performance of 72% is maintained even at high current density of 50 mA cm−2, indicating that the CC@CCH@N2C4-DH electrode is a very prospective electrode material. [ABSTRACT FROM AUTHOR]

316L stainless steel specimens were manufactured by additive/subtractive hybrid manufacturing (ASHM). The densification level, mi-crostructure, microhardness and residual stress characterization in the different zones of the part were investigated. The density was determined by the Archimedes method, and the density measurement was divided into three regions, namely, the bottom, middle and top zones. The results show that the middle zone has a much smoother melting surface and that a relative density of nearly 100 % was achieved for the part in this study. The hardness profiles at room temperature, along the width and height directions of the cross-section of the top and bottom zones, were also studied. The residual stress was evaluated by X-ray diffraction (XRD) for the 316L SS specimen fabricated by the ASHM process, and it was compared with a specimen manufactured by the additive laser directed energy deposition (DED) process. The results show that the top and bottom zones exhibit tensile stress, and compressive stress occurs in the middle area. Moreover, the residual stress of ASHM shows a slightly smaller trend than that of the simplex DED due to the stress relaxation of the subsequent subtractive milling. These results may offer guidance for ASHM-fabricated 316L parts. [ABSTRACT FROM AUTHOR]

An enormous amount of research effort goes into the manufacturing process for additive manufacturing (AM) or subtractive manufacturing (SM) process for property microstructure. Moreover, additive/subtractive hybrid manufacturing (ASHM), which combines additive and subtractive processes in a single machine, has provided an important opportunity to increase the high percentage of stock utilization and produce complex functional components. However, the system comprehensive investigation and the study of ASHM-manufactured parts by various process parameters have rarely been reported. The present paper depicted the effect of laser energy density (ψ) on the phase change, density, microstructure, Vickers hardness, and tensile testing within the ASHM specimens. It was observed that the highest Vickers microhardness, the largest tensile strength, and the attendant ductility were gained at ψ =222 J/mm3, the most excellent value, which was put down to the high density and relatively fine grains. The results of this study have a better knowledge of the ASHM method to produce a high surface state and mechanical behavior 316L SS component by governing laser energy density (ψ). [ABSTRACT FROM AUTHOR]

In this work, nitrogen-doped hierarchical porous graphene-like carbon (NCFC) with coral flower structure is synthesized by an eco-friendly and inexpensive template carbonization method, with cellulose acetate (CA) as carbon precursor, MgO as template, and urea as nitrogen agent. The as-synthesized NCFC features loose coral flower composed of ultra-thin graphene-like sheets and has a high specific surface area of 937 m2 g−1. As the electrode material for supercapacitors, the NCFC shows a high capacitance of 333 F g−1 at 1 A g−1 in 1 mol L−1 H2SO4 electrolyte and a good rate performance (the specific capacitance at 10 A g−1 retains 84% relative to 1 A g−1), and excellent cycle stability with 100% capacitance retention after 10,000 cycles. The symmetric supercapacitor (SSC) was assembled by using NCFC in 1 mol L−1 H2SO4 electrolyte. The device exhibits the maximum energy density of 21 W h kg−1 at a power density of 750 W kg−1 in a potential window of 0 to 1.4 V. Our work is expected to pave a new way for scale-up production of high-performance graphene-like carbon from natural cellulose with a simple, eco-friendly, and low-cost method. [ABSTRACT FROM AUTHOR]

Avian leukosis virus (ALV) caused tremendous economic losses to poultry industry all over the world, especially in China. One natural recombinant ALV strain, designated as HB2015032, was isolated from indigenous chickens with neoplastic diseases in Hubei, China. The complete proviral genome of HB2015032 is 7703 bp in length. Sequence analysis showed that the Env of HB2015032 exhibited 99.3% similarity with that of a ALV subgroup K (ALV-K) isolate JS11C1 at amino acid level. Phylogenetic analysis revealed that both gp85 and gp37 of HB2015032 were clustered in the same branch with JS11C1 and other ALV-K strains isolated from Chinese indigenous chickens in recent years. However, the pol gene, the 3′ untranslated region (3′ UTR), and the 3′ long terminal repeat (3′ LTR) of HB2015032 were more closely related to ALV-J prototype HPRS-103, and clustered in the same branch with ALV-J strains. Furthermore, the pol gene of HB2015032 contained a premature stop codon that resulted in a truncated Pol protein with 22 amino acid residues missing, which was a unique feature of the pol gene of ALV-J. 3′UTR of HB2015032 containing entire DR1, E element and U3. E element of HB2015032 contained one base deletion, which resulted in a c-Ets-1 binding site. In addition, U3 region of HB2015032 contains most of the transcription regulatory elements of ALV-J, including two CAAT boxes, Y boxes, CArG boxes, PRE boxes, NFAP-1 boxes, and one TATA box. These results suggest that isolate HB2015032 was a novel recombinant ALV-K containing the ALV-K env gene and the ALV-J backbone and exhibiting high pathogenicity. [ABSTRACT FROM AUTHOR]

The ceramic has extensive applications in aeronautics and transportation industry because of outstanding properties, but the processing performance is poor. The carbon fiber-reinforced SiC matrix composite (Cf/SiC) is proposed to improve machining performance. The carbon fibers have important effects on surface quality and forces when machining Cf/SiC materials. But there are few investigations about the related contents. To fill these gaps by comparing SiC and Cf/SiC composites is the main objective of this study. The Cf/SiC materials were machined in two different directions. To explore the grinding mechanism, some evaluation parameters were investigated. The extension of cracks is the main removal method during grinding process of SiC. While matrix craze, fiber fracture, and interfacial debonding are the main remove methods of Cf/SiC composites. While grinding 2.5 D Cf/SiC material, fiber pullout, outcrop, fractures, wear, interfacial debonding, and matrix cracks were the major failure forms. During machining, the roughness of the machined surface decreased with reducing grinding speed vs, whereas the grinding depth ap and feed speed vw brought contrary effects. Meanwhile, the grinding forces gradually improved with increasing ap and vw, and decreasing vs. On the basis of conclusions, the surface roughness and grinding forces of the SiC and 2.5 D Cf/SiC materials could be derived. This series of analysis and researches provides useful technical support on understanding the grinding mechanism of SiC and 2.5 D Cf/SiC material. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study of the tensile performance, heat treatment, fracture, decrease of residual stress, second-phase particle and microstructures of a 316L stainless steel fabricated by directed laser deposition (DLD) and thermal milling (starting milling temperature at 250 ± 50 °C), a typical hybrid additive and subtractive manufacturing process. Experiments of different post-heat treatment temperatures and tensile tests at room temperature were performed. The residual stress was eliminated with heat treatment at 400 °C for 2 h, and the average residual stress decreased 53.7% while the yield strength and ultimate strength decreased slightly. The fracture surfaces of different heat treatment temperatures were observed. The typical ductile fracture microstructures of dimples were seen in almost all specimens whenever the heat treatment temperature was low or high. The evolution of dimples from formation to destruction by heat treatment was analyzed. The different morphology and composition of the second-phase particles of different heat treatment temperatures were compared. The yield strength of 427.5 MPa, the ultimate strength of 599.27 MPa, and the elongation of 36.48% showed the new hybrid manufacturing technology could be used for further fabrication of components. [ABSTRACT FROM AUTHOR]

A facile one-step strategy is established to prepare nitrogen doped three-dimensional (3D) hierarchical porous carbon from buckwheat husk, in which the synchronous activation and nitrogen-doping is fulfilled via using KOH and urea. The obtained sample (BSCN-700) possesses an ultrahigh specific surface area of 2794.5 m2 g−1 with a unique carbon frame. The electrochemical measurements indicate that the resultant BSCN-700 exhibits a high specific capacitance of 326 F g−1 at current density of 1 A g−1, with good rate capability (78.4% capacitance retention at 100 A g−1) in 6 M KOH electrolyte. Furthermore, the as-prepared sample was used to assemble a symmetric supercapacitor filled with 6 M KOH electrolyte. As a result, the BSCN-700 symmetric supercapacitor displays a high energy density of 20.4 Wh kg−1 at a power density of 699 W kg−1 and good cycling stability which retains 95% of the initial capacitance at 5 A g−1 after 5000 cycles. [ABSTRACT FROM AUTHOR]

In the present work, we report a simple two-step process to fabricate hierarchical porous carbon from biomass. The so-called two-step refers to hydrothermal carbonization of cypress coats followed by activation with KOH. The morphology and porous parameters of the resulting porous carbon can be controlled by adjusting KOH/carbon mass ratio during activating stage. The optimal sample (SHPC-2) has a hierarchically porous structure containing micropores and meso-/macropores, high specific surface areas (1325.9 m2 g− 1) with appropriate pore size and hydrophilous surface properties due to rich nitrogen and oxygen co-doping. The electrochemical measurements show the as-prepared SHPC-2 exhibits a high specific capacitance (345 and 330 F g− 1 at 1.0 A g− 1) and better rate capability (75.4% and 87.8% capacitance retention at 50 A g− 1) in 1 M H2SO4 and 6 M KOH, respectively. Furthermore, the assembled symmetric supercapacitor based on SHPC-2 and filled with 1 M Na2SO4 electrolyte delivers an outstanding energy storage performance (energy density of 30.5 W h kg− 1 at power density 900 W kg− 1) with good cycling stability (86.2% retention after 10000 cycles at 5 A g− 1). These results indicate that the eco-friendly carbon materials derived from biomass have a huge potential in the applications of high-performance electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Fe3O4/P(GMA-DVB)/PAMAM/Au microspheres are fabricated to research the catalytic performances to 4-nitrophenol. In the preparation process, Fe3O4 microspheres act as magnetic cores, PAMAM dendrimers growing up on the surface of P(GMA-DVB) polymer work as carriers, and Au nanoparticles serve as catalytic materials. The stability of the prepared microspheres is evaluated by successively catalytic experiments to measure the conversion of 4-nitrophenol, and catalytic efficiency can still maintain up to 78.7% after ten cycles. Moreover, the effects of major factors including the concentration of the prepared microspheres and the temperature of reaction system on the conversion of 4-nitrophenol are also investigated in detail. The manuscript reveals that 4-nitrophenol can be almost converted to 4-aminophenol within 7 min at 45 °C in the case of using 1.0 g/L Fe3O4/P(GMA-DVB)/PAMAM/Au microspheres. Such excellent catalytic properties are ascribed to the optimum structure of the prepared microspheres, which favors the sufficient contact between Au nanoparticles and 4-nitrophenol. The results and strategies exhibited here provide insight into the preparation of sophisticated structures of catalysts to treat wastewater. [ABSTRACT FROM AUTHOR]

This paper firstly focused on analyzing the machining accuracy of low-speed wire electrical discharge turning (LS-WEDT), and the practical machining is carried out via fabrication of micro parts. Firstly, the concept of LS-WEDT method is proposed and the rotating apparatus is designed and fabricated to make the low-speed wire electrical discharge machine realize the machining of rotary structures. Besides, the effects of machining parameter on roundness of YG8 hard alloy rotary workpiece machined by LS-WEDT are discussed. Besides, experimental results revealed that high consistent accuracy of rotary groove width can be obtained with the wire speed of 45 to 75 mm/s, feed speed of 0.8~1 mm/min, wire tension of 14~16 N, and the lower rotating speed is conductive to obtain high rotary groove accuracy. Furthermore, the intricate relationships of rotating speed, feed speed, and discharge energy for LS-WEDT process are revealed and optimum speed parameters are given for low and high discharge energy, respectively. Finally, using this new process, micro cylindrical shaft and the micro two-edged cutter are successfully fabricated. More importantly, the flexibility of LS-WEDT makes it have superiority in fabricating complicated structures not just limited to the simple rotary parts like cylinder. Consequently, experimental results indicated that spirals microelectrode with average diameter of 395.64 μm and length of 1673.64 μm and the three spirals micro-cutting tool with average diameter of 796.20 μm and length of 2011.15 μm can be firstly and successfully manufactured by LS-WEDT method. [ABSTRACT FROM AUTHOR]

In recent years, additive manufacturing (AM) has been developed for industrial applications due to its superior performance, such as in building complex parts, which are especially difficult to build when using traditional methods. However, the surface quality, and dimensional and geometric accuracies of AM parts do not exceed conventionally machined parts, which hinders the AM applications. To overcome these limitations, hybrid manufacturing (HM) technology, which combines AM and subtractive manufacturing (SM) technologies in a single workstation has received a great deal of attention in academic and industrial circles to enhance material utilization, part complexity and quality control when producing functional parts. In this paper, we present research achievements using ANSI 316L stainless steel parts via the HM process and analysis of its surface morphology and microstructural characteristics, densification behaviour and mechanical properties. Specimens before and after heat treatment were analysed and compared. The study also dealt with material characterization via the Archimedes method, scanning electron microscopy (SEM), X-ray polycrystalline diffractometer (XRD) and tensile measurements. This study provides a valuable guide to determining the effectiveness of the HM process and its use when producing engineering parts. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI)/polysulfone (PSF) composite films are successfully prepared by phase separation and one-step in-situ polymerization. It is found that the head-on face (in contact with solution) of the films is green while the back face is white. The chemical component and the surface morphology of both surfaces of the films are characterized by FT-IR spectra and SEM, respectively. The effect of the polymerization temperature, time and concentration of the reactants on the electrical properties of the films are discussed in details. The thermo-oxidative degradation of the films is studied by thermogravimetric analysis (TGA). The results indicate that the thermal stability of the PANI/PSF films is higher than that of the pure PSF film. [ABSTRACT FROM AUTHOR]

In this study, a novel method was used to prepare well-separated and spherical tricobalt tetraoxide (Co3O4) nanosized particles. The overall process involves three steps: preparation of insoluble carboxyl-containing grafted starch copolymer (ISC), formation of precursor (ISC-Co), decomposition of ISC-Co, and phase transition of Co3O4 nanoparticles. The Infrared spectra used for ISC and ISC-Co are discussed. The decomposition of the precursor was studied by thermogravimetric-differential thermal analysis, the crystalline phase was characterized by x-ray diffraction, and the size distribution and shape of particles were observed by transmission electron microscopy. [ABSTRACT FROM AUTHOR]

A composite nanoenzyme was used in a sandwich-type electrochemical immunoassay for the carcinoembryonic antigen (CEA). Hierarchically porous palladium nanospheres (Pd NPs) were functionalized with glutathione-capped gold nanoparticles (G-Au NPs) and then loaded onto graphene oxide (GO) to obtain a peroxidase mimicking nanoenzyme of type GO-supported G-Au/Pd. The composite can catalyze the oxidation of the substrate tetramethylbenzidine (TMB) by H2O2 to give blue-colored oxidized TMB within only 20 s. This strong peroxidase activity, good conductivity and high specific surface area of the material make it a useful label for secondary antibodies (Ab2) for the detection of CEA. The cotton-like electrodeposited gold nanoparticles with good electrical conductivity were used to immobilize primary antibody (Ab1). The amperometric immunoassay has a detection range that extends from 10 fg·mL−1 to 100 ng·mL−1 at a working potential of −0.4 V with addition of 5 mmol·L−1 H2O2 as electrochemically active substrate, and the detection limit is as low as 3.2 fg·mL−1 (S/N = 3). [ABSTRACT FROM AUTHOR]

Based on measles surveillance in Shanghai, People's Republic of China, from 2006 to 2015, we found that measles virus isolates from 40 throat swab samples exhibited atypical cytopathic effects in Vero/hSLAM cells, which was found to be a result of coinfection with measles virus (MeV) and human herpes simplex virus type 1 (HSV-1). Serological and molecular approaches were used to confirm and characterize the coinfections in these patients. Among the 40 measles cases, measles-specific IgM was detected in 37 cases, while measles-specific IgG was detected in 27 cases. HSV-1-specific IgM and IgG were detected in 7 and 34 cases, respectively, suggesting that most of the MeV infections were primary, but that HSV-1 infection was due to the reactivation of latent virus in most cases. The titers of HSV-1 IgG in patients with either measles or measles-HSV-1 coinfection were significantly higher than those in the healthy group (P = 0.0026 and P < 0.0001, respectively); however, there was no significant difference in the titers of HSV-1 IgG in the MeV and MeV-HSV-1 coinfection patients (P = 0.105). Nucleic acids from MeV and HSV-1 were detected in 40 and 39 throat swabs, respectively. Twenty five MeV RNA sequences were genotyped, and all represented genotype H1, which is the endemic genotype in China. Sequences from the glycoprotein G gene of HSV-1 were used to classify the isolates into two distinct phylogenetic groups: 34 belonged to group A and 3 belonged to group B. [ABSTRACT FROM AUTHOR]