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Complex and heterogeneous structures of lignin impede its further conversion and valorization. Herein, three technical lignins (from softwood, hardwood, and grass) were fractionated with acetone solvent to reduce their structural heterogeneity, which were then blended with poly-(butylene adipate-co-terephthalate) (PBAT) to fabricate biodegradable bio-composites. Macromolecular structures of lignins and their effects on the properties of lignin/PBAT composites were thoroughly investigated. Results showed that all fractionated lignin composites displayed better properties. Particularly, the raw and fractionated softwood lignin-based composites exhibited superior performance compared with others. Benefiting from the lower molecular weight, hydroxyl groups, and condensation, acetone fractionated softwood lignin presented the lowest T

Alcohol consumption is a critical risk factor contributing to a verity of human diseases. The incidence of alcohol use disorder increases across adolescence in recent years. Accumulating line of evidence suggests that alcohol-induced changes of DNA cytosine methylation (5-methyl-2′-deoxycytidine, 5mC) in genomes play an important role in the development of diseases. However, systemic investigation of the effects of adolescent alcohol exposure on DNA and RNA modifications is still lacked. Especially, there hasn't been any report to study the effects of alcohol exposure on RNA modifications. Similar to DNA modifications, RNA modifications recently have been identified to function as new regulators in modulating numbers of biological processes. In the current study, we systematically investigated the effects of alcohol exposure on both DNA and RNA modifications in peripheral blood of adolescent rats by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The developed LC-ESI-MS/MS method enabled the sensitive and accurate determination of 2 DNA modifications and 12 RNA modifications. As for the alcohol exposure experiments, the adolescent rats were intraperitoneally injected with ethanol with an interval of one day for a total 14 days. The quantification results by LC-ESI-MS/MS analysis showed that adolescent alcohol exposure could alter both DNA and RNA modifications in peripheral blood. Specifically, we observed an overall decreased trend of RNA modifications. The discovery of the significant alteration of the levels of DNA and RNA modifications under alcohol exposure indicates that alcohol consumption may increase the risk of the incidence and development of diseases through dysregulating DNA and RNA modifications.

Cell death is an important physiological phenomenon in life. It can be programmed or unprogrammed. Unprogrammed cell death is usually induced by abiotic or biotic stress. Recent studies have shown that many proteins regulate both cell death and immunity in plants. Here, we provide a review on the advances in plant immunity with cell death, especially the molecular regulation and underlying mechanisms of those proteins involved in both cell death and plant immunity. In addition, we discuss potential approaches toward improving plant immunity without compromising plant growth.

5-Methylcytosine (5mC) is the most important epigenetic modification in mammals. The active DNA demethylation could be achieved through the ten-eleven translocation (TET) protein-mediated oxidization of 5mC with the generation of 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC). It has been known that 5mC, 5hmC and 5fC play critical roles in modulating gene expression. However, unlike the 5mC, 5hmC, and 5fC, the functions of 5caC are still underexplored. Investigation of the functions of 5caC relies on the accurate quantification and localization analysis of 5caC in DNA. In the current study, we developed a method by chemical conversion in conjugation with ligation-based real-time quantitative PCR (qPCR) for the site-specific quantification of 5caC in DNA. This method depends on the selective conversion of 5caC to form dihydrouracil (DHU) by pyridine borane treatment. DHU behaves like thymine and pairs with adenine (DHU-A). Thus, the chemical conversion by pyridine borane leads to the transformation of base paring from 5caC-G to DHU-A, which is utilized to achieve the site-specific detection and quantification of 5caC in DNA. As a proof-of-concept, the developed method was successfully applied in the site-specific quantification of 5caC in synthesized DNA spiked in complex biological samples. The method is rapid, straightforward and cost-effective, and shows promising in promoting the investigation of the functional roles of 5caC in future study.

The rapid spread of the coronavirus disease (COVID-19) pandemic in over 200 countries poses a substantial threat to human health. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, can be discharged with feces into the drainage system. However, a comprehensive understanding of the occurrence, presence, and potential transmission of SARS-CoV-2 in sewers, especially in community sewers, is still lacking. This study investigated the virus occurrence by viral nucleic acid testing in vent stacks, septic tanks, and the main sewer outlets of community where confirmed patients had lived during the outbreak of the epidemic in Wuhan, China. The results indicated that the risk of long-term emission of SARS-CoV-2 to the environment via vent stacks of buildings was low after confirmed patients were hospitalized. SARS-CoV-2 were mainly detected in the liquid phase, as opposed to being detected in aerosols, and its RNA in the sewage of septic tanks could be detected for only four days after confirmed patients were hospitalized. The surveillance of SARS-CoV-2 in sewage could be a sensitive indicator for the possible presence of asymptomatic patients in the community, though the viral concentration could be diluted more than 10 times, depending on the sampling site, as indicated by the

Circular RNA (circRNA) plays an important role in osteoarthritis (OA) progression. Circ_0001721 has been noted to be significantly overexpressed in OA patients, but its function in OA progression remain unclear. The purpose of this study was to investigate the role and mechanism of circ_0001721 in OA progression.Interleukin-1β (IL-1β)-induced chondrocytes were used to mimic OA cell model in vitro. The expression of circ_0001721, microRNA (miR)-373-3p and CXC chemokine receptor 4 (CXCR4) was examined by quantitative real-time PCR. The concentrations of inflammatory factors were assessed by ELISA assay. Cell proliferation and apoptosis were determined by MTT assay, EdU assay and flow cytometry. Protein levels were detected by western blot analysis. The interaction between miR-373-3p and circ_0001721 or CXCR4 was confirmed by dual-luciferase reporter assay, RIP assay and RNA pull-down assay.Our results showed that circ_0001721 was highly expressed in OA patients and IL-1β-induced chondrocytes. IL-1β treatment could suppress the proliferation, while promote the apoptosis, extracellular matrix (ECM) degradation and inflammation of chondrocytes. Knockdown of circ_0001721 alleviated IL-1β-induced chondrocyte injury. MiR-373-3p could be sponged by circ_0001721, and its inhibitor reversed the regulation of circ_0001721 knockdown on IL-1β-induced chondrocyte injury. CXCR4 was a target of miR-373-3p, and circ_0001721 could sponge miR-373-3p to regulate CXCR4. Furthermore, miR-373-3p overexpression inhibited IL-1β-induced chondrocyte injury, and these effects could be overturned by CXCR4 upregulation.Our data confirmed that circ_0001721 knockdown alleviated IL-1β-induced chondrocyte injury by miR-373-3p/CXCR4 axis, which suggested that circ_0001721 might be a potential therapeutic target for OA.

Peak elimination of cross structures has become a challenging issue in wire and arc additive manufacturing. This study proposes a control strategy to eliminate peaks in gas tungsten arc (GTA)-based additive manufacturing, i.e., adjusting the amount of filler materials at the peaks based on arc voltage signals. A novel algorithm, combining the anti-impulse interference moving average and the wavelet packet transform, is developed to filter disturbances in the arc voltage, and the deviation between the maximum and the minimum is less than 0.04 V. A Fuzzy-PID closed-loop controller is designed for arc voltage control and its parameters are determined by conducting multi-layer experiments. Comparison tests with open-loop and closed-loop controlled wire feed speeds are carried out to fabricate cross structures in GTA-based additive manufacturing. The results show that the deviation of the detected and given arc voltage at the peaks in the open-loop control test is more than 9 V, and that in the closed-loop control test can be controlled within 1 V. The peak generation in the open-loop control test results in the process termination. By contrast, the proposed control strategy using the arc voltage detection and filler wire control technique is extremely effective to eliminate the peaks in cross structures.

During selective laser melting (SLM) process, the correlation between thermal behavior and complex microstructure must be clarified. The present study investigates the effect of laser power and scan speed on thermal behavior and solidification structures of SLM-produced high strength tool steel. A three-dimensional finite element model was built to simulate the thermal behavior in SLM process. The simulation results show that correlativity exists between the process parameters (laser energy density) and the maximum temperature, cooling rate, temperature gradient and solidification rate. Scan speed has more significant impact on the cooling rate and solidification rate than laser power. The sub-grain patterns of the part presents predominantly cellular, elongated cellular and columnar structure. The formation of these sub-grain microstructures in the molten pool was controlled by the gradient cooling rate (from 5.6×105 to 3.4×106 °C/s) and temperature gradient (from 5.0 to 30 °C/μm). The columnar structure are elongated with the increment of the temperature gradient. The grain size of the microstructure become finer with the increase of laser power or scan speed. And the gradient microstructure has a significant impact on its microhardness properties.

Robust measurement of layer geometry can help better understand the complex deposition process and provide feedback control to increase process stability of wire and arc additive manufacturing (WAAM). In this study, a virtual binocular vision sensing system is designed to measure the layer width and torch height from top layer simultaneously. Considering that stereo matching is the most crucial step for 3-D reconstruction in stereovision sensing, various matching algorithms, i.e. adaptive Census transform (ACT), global-based crosswise iteration (GCI), and semi global matching (SGM), are employed to calculate disparity images of image pairs. The matching algorithms are tested based on the standard datasets, indicating that the highest matching accuracy comes from the GCI matching algorithm. Then, a standard cylinder is taken as an example to verify the effectiveness of the sensing system and algorithms. The results show that the cylinder width errors with the ACT, GCI and SGM matching algorithms are 3.17%, 3.02%, and 3.08%, respectively, while the cylinder height errors are 5.83%, 4.15%, and 4.83%, respectively. Finally, layer geometries in WAAM with various process parameters are determined. The width and height errors of layer geometry with the GCI matching algorithm are less than 3.2%. This study will lay a solid foundation for subsequent feedback control for layer geometry in WAAM.

In this work, a novel homogeneous electrochemical aptasensor based on electrically assisted bond and tetraferrocene signal amplification was constructed for thrombin detection. Importantly, modification of the electrode is not necessary for this sensor, requiring only the construction of a simple and efficient probe. In addition, a brand new signal marker-tetraferrocene, containing four ferrocene molecules, was employed as a label to the terminal position of the probe. Compared with a single ferrocene moiety, tetraferrocene possesses a larger amplification signal for rapid detection of thrombin. In the detection of thrombin, the selected aptamer probe with a stem-loop structure was labeled with tetraferrocene at the 3' terminal and thiol at the 5' terminal, respectively. Confinement of the thiol to the stem-loop structure of the probe, the ability of thiol to reach the surface of electrode lossed even with the aid of the applied potential. However, upon treatment with the target protein of thrombin the stem-loop structure opened, promoting rapid attachment of the thiol group to the electrode interface generating Au-S self-assembly with the action of potential-assistance. The electrochemical signal of tetraferrocene could be measured by differential pulse voltammetry (DPV), which was subsequently used for target quantitative detection. This strategy displayed a detection limit as low as 0.126 pM, and an inherently high specificity for the detection of a single mismatch. Moreover, it exhibited advanced specificity against common interfering proteins.

Hexagonal boron nitride (h-BN), with unique structural and properties, has shown enormous potential toward variety of possible applications. By virtue of partially-ionic character of BN chemical bonds and usually large specific surface area, h-BN-related nanostructures exhibit appealing adsorption properties, which can be widely applied for separation and purification towards energy and environment treatment. In this review, recent progress in designing h-BN micro, nano-structure, controlled synthesis, performance optimizing as well as energy and environment-related adsorption applications are summarized. Strategies to tailor the h-BN can be classified as morphology control, element doping, defect control and surface modification, focusing on how to optimize the adsorption performance. In order to insight the intrinsic mechanism of tuning strategies for property optimization, the significant adsorption applications of h-BN towards hydrogen storage, CO2 capture, pollutants removal from water and adsorption desulfurization are presented.

Room temperature Na-ion batteries (SIBs) show great potential for use as renewable energy storage systems. However, the large-scale application of SIBs has been hindered by the lack of an ideal SIBs anode material. We synthesized MoS2 on carbonized graphene-chitosan (G-C) using the hydrothermal method. The strong interaction between the MoS2 and the G-C greatly improved the electron transport rate and maintained the structural stability of the electrode, which lead to both an excellent rate capability and long cycle stability. The G-C monolith was proven to enhance the electrical conductivity of the composites and served as a matrix for uniformly dispersing active MoS2 nanosheets (NSs), as well as being a buffer material to adapt to changes in volume during the cycle. Serving as an anode material for SIBs, the MoS2-G-C electrode showed good cycling stability (527.3 mAh g−1 at 100 mA g−1 after 200 cycles), excellent rate capability, and a long cycle life (439.1 mAh g−1 at 1A g−1 after 200 cycles). Keywords: Na-ion batteries, Carbon-based materials, MoS2, Long cycle life

Additive manufacturing employing Gas Tungsten Arc (GTA) as the heat source is capable of fabricating fully dense metal components layer upon layer. However, this process is sensitive to various disturbances and needs on-line detection and adjustments. In this work, a visual sensor, comprising a camera and composite filters, is developed for automatically real-time sensing of the fabrication process. The aim is to keep stable manufacture, and the deviations of the deposited height are compensated by designing an integral separation PID controller to adjust the wire feed speed in the next layer. The optical measurement technique and the controller are estimated via building multi-layer single-pass walls. The results show that the process stability in GTA-based additive manufacturing is well controlled when the designed visual sensor and the proposed closed-loop controller are applied.

A gas exfoliation strategy for controllable preparation of boron nitride (BN) nanosheets with few-layered structure were reported. The green exfoliation process provides the BN nanosheets remarkable increment of adsorption capacities to organic contaminants, which is ascribed to better exposure of active sites originating from the larger surface area and thinner layer. Moreover, the prepared BN also exhibits outstanding recyclability.

Automatic detection of deposition height is one of the key technologies for metal components fabricated in robotic gas tungsten arc (GTA) based additive manufacturing. In this research, the deposition height, defined as the tungsten tip to the top layer distance, is monitored by a passive vision sensor consisting of a camera and optical filters. Characteristic parameters of molten pool tail are extracted by designed image processing algorithms. An innovative tracking algorithm is developed to determine the location of the solid-liquid separation point at the molten pool tail by means of continuous images. Finally, the detection approach is verified through depositing multi-layer single-pass parts, proving the excellent effectiveness and anti-interference ability of the tracking algorithm in robotic GTA-based additive manufacturing.

Translocator protein (TSPO) is an 18-kDa transmembrane protein found primarily in the mitochondrial outer membrane, and it is implicated in inflammatory responses, such as cytokine release. Koumine (KM) is an indole alkaloid extracted from Gelsemium elegans Benth. It has been reported to be a high-affinity ligand of TSPO and to exert anti-inflammatory and immunomodulatory effects in our recent studies. However, the protective effect of KM on sepsis-associated liver injury (SALI) and its mechanisms are unknown.To explore the role of TSPO in SALI and then further explore the protective effect and mechanism of KM on SALI.The effect of KM on the survival rate of septic mice was confirmed in mouse models of caecal ligation and puncture (CLP)-induced and lipopolysaccharide (LPS)-induced sepsis. The protective effect of KM on CLP-induced SALI was comprehensively evaluated by observing the morphology of the mouse liver and measuring liver injury markers. The serum cytokine content was detected in mice by flow cytometry. Macrophage polarization in the liver was examined using western blotting. TSPO knockout mice were used to explore the role of TSPO in sepsis liver injury and verify the protective effect of KM on sepsis liver injury through TSPO.KM significantly improved the survival rate of both LPS- and CLP-induced sepsis in mice. KM has a significant liver protective effect on CLP-induced sepsis in mice. KM treatment ameliorated liver ischaemia, improved liver pathological injuries, and decreased the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and proinflammatory cytokines in serum. Western blotting results showed that KM inhibited M1 polarization of macrophages and promoted M2 polarization. In TSPO knockout mice, we found that TSPO knockout can improve the survival rate of septic mice, ameliorate liver ischaemia, improve liver pathological injuries, and decrease the levels of ALT, AST, and LDH. In addition, TSPO knockout inhibits the M1 polarization of macrophages in the liver of septic mice and promotes M2 polarization and the serum levels of proinflammatory cytokines. Interestingly, in TSPO knockout septic mice, these protective effects of KM were no longer effective.We report for the first time that TSPO plays a critical role in sepsis-associated liver injury by regulating the polarization of liver macrophages and reducing the inflammatory response. KM, a TSPO ligand, is a potentially desirable candidate for the treatment of SALI that may regulate macrophage M1/M2 polarization through TSPO in the liver.