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A crystal plasticity coupled twinning phase field (CP-TPF) model was developed to investigate the plastic deformation of magnesium (Mg) single crystal. Three types of slip systems, i.e., basal, prismatic, and pyramidal slip ones were considered in the crystal plasticity model, while the crystalline, gradient, and elastic energies were considered in the phase field model for twinning. The results show that during the twinning induced by the shear loading along the twinning direction, the stress levels at different stages and the mobility of twin interfaces in different directions show huge differences. The twins are lenticular at the early stage and show a flat plane during the growth, and the activation of basal slip follows the twinning deformation. Non-basal slip is activated after the matrix is completely transformed into the twins. Different plastic deformation modes are observed in Mg single crystal with different crystalline orientations during one tensile-compressive loading cycle: The corresponding deformation modes are twinning-detwinning-pyramidal slip-retwinning when the loading direction is parallel to the c axis and are prismatic slip-twinning & prismatic slip-twinning-detwinning when the loading direction is perpendicular to the c axis of the single crystal, a strong tension-compression asymmetry is shown in both the two simulations; while only the basal slip occurs, and no tension-compression asymmetry is observed when the angle between the loading direction and the c axis is 45°. [ABSTRACT FROM AUTHOR]

Multiple-input single-output (MISO) have extraordinary propagation properties, making it possible to further improve the performance of underwater wireless optical communication (UWOC). In this paper, a tilted MISO-UWOC system consists of a beam array and an aperture averaged detector, academically called multiple-input aperture-average (MIAA) systems, are proposed. Different from the original approach where beams are parallel to each other, the tilted approach has a series of multiple beam transmitters individually aimed at the receiver. The MIAA systems are extensively compared to single-input single-output (SISO) systems on scintillation index and SNR for various oceanic turbulence conditions and system configurations by wave optics simulation (WOS). Our results reveal that tilted MIAA systems show tremendous advantages over the parallel MIAA systems including the reduced scintillation and the improved signal to noise ratio (SNR) under the same configuration. The obtained results can be useful for the UWOC system design. [ABSTRACT FROM AUTHOR]

Optofluidic laser (OFL) technology, as an emerging technology combining microfluidics and laser technology, offers many unique advantages in sensing applications and has become a research hotspot for highly-sensitive intracavity biochemical analysis. Biochemical sensors based on OFLs can detect changes in biochemical parameters by using significant changes in laser output characteristics, so as to achieve high detection sensitivity. Here, we provide an overview of OFLs with a focus on their constructions, the design of OFL-based biochemical sensors, and their applications in biochemical analysis. Firstly, the three elements of an OFL, including the optical microcavity, gain medium, and pump source, are described systematically. After explaining the basic principles and characterization of OFLs for biochemical sensing, the current research progress of OFL-based biochemical sensors is summarized and analyzed according to the combination of OFLs with different assay techniques. This is followed by a discussion of the research on OFLs at the level of biological macromolecules, cells, and tissues. Finally, in view of the applications of OFLs in the field of biochemical sensing, the current challenges and future development directions are briefly discussed. [ABSTRACT FROM AUTHOR]

Saline‐alkali stress (SS) is a common abiotic stress affecting crop cultivation worldwide, seriously inhibiting plant growth and biomass accumulation. Melatonin has been proven to relieve the inhibition of multiple abiotic stresses on plant growth. Therefore, soybean cultivars Heihe 49 (HH49, SS‐tolerant) and Henong 95 (HN95, SS‐sensitive) were pot‐cultured in SS soil and then treated with 300 μM melatonin at the V1 stage, when the first trifoliate leaves were fully unfolded, to investigate if melatonin has an effect on SS. SS increased reactive oxygen species (ROS) accumulation in soybean leaves and thereby induced DNA oxidative damage. In addition, SS retarded cell growth and decreased the mesophyll cell size, chloroplast number, photosynthetic pigment content, which further reduced the light energy capture and electron transport rate in soybean leaves, and affected carbohydrate accumulation and metabolism. However, melatonin treatment reduced SS‐induced ROS accumulation in the soybean leaves by increasing antioxidant content and oxidase activity. Effective removal of ROS reduced SS‐induced DNA oxidative damage in the soybean leaf genome, which was represented by decreased random‐amplified polymorphic DNA polymorphism, 8‐hydroxy‐20‐deoxyguanine content, and relative density of apurinic/apyrimidinic‐sites. Melatonin treatment also increased the volume of mesophyll cells, the numbers of chloroplast and starch grains, the contents of chlorophyll a and b and carotenoids in soybean seedling leaves treated with SS, thereby increasing the efficiency of effective light capture and electron transfer and improving photosynthesis. Subsequently, carbohydrate accumulation and metabolism in soybean leaves under SS were improved by melatonin treatment, which contributes to providing basic substances and energy for cell growth and metabolism, ultimately improving soybean SS tolerance. [ABSTRACT FROM AUTHOR]

Salt stress is a common abiotic stress that negatively affects crop growth and yield. However, there have been significant differences found on the effect degree and management mechanism in plants under neutral salt stress and alkaline stress. In this study, two soybean cultivars, Heihe 49 (HH49, saline-alkali stress tolerant) and Henong 95 (HN95, saline-alkali stress sensitive), were hydroponically cultured and treated with salt solutions of 25, 50, and 75 mM Na+ in the form of NaCl, Na2SO4, NaHCO3, and Na2CO3. Plants treated with alkaline stress (NaHCO3 and Na2CO3) showed a greater decrease in root growth and root activity of both soybean cultivar seedlings than that under neutral salt stresses (NaCl and Na2SO4) with 25–75 mM Na+ concentration. Alkaline stress (25–50 mM Na+ content) activated a higher ability of antioxidant defense (by enhancing the activists of superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX)) and increased the content of soluble sugars to a higher level than that under neutral salt stresses. However, 75 mM Na+ content salt treatments reduced antioxidant enzyme activities and osmotic regulating substance content. Furthermore, alkaline salt and neutral salt stress was able to induce DNA damage and cell cycle arrest in HH49 and HN95 seedling roots. Treatment with Na2CO3 induced the least random amplification polymorphic DNA (RAPD) polymorphism in soybean seedling roots among all salt treatments, which could have been related to the early cell cycle arrest. [ABSTRACT FROM AUTHOR]

• A phase field model coupling the precipitation of Ni 4 Ti 3 and B2-B19′ martensite transformation is proposed. • The precipitate-dependent functional properties of single-crystal, polycrystalline, and gradient-nanograined NiTi SMAs are simulated. • The effects of precipitate density, grain orientation range, and gradient-distributed precipitates are addressed, and the underlying microscopic mechanisms are revealed. Ni 4 Ti 3 precipitates, which generally exist in aged Ni-rich NiTi shape memory alloys (SMAs), can have a profound effect on material properties. However, the fundamental insights into the effects of Ni 4 Ti 3 precipitates on the functional properties, including the superelasticity (SE), elastocaloric effect (eCE), and shape memory effects (SMEs), are not well understood yet, especially those originating from the B2-B19′ martensite transformation (MT). In this work, a phase field model coupling the precipitation of Ni 4 Ti 3 and the B2-B19′ MT is proposed, where the thermo-mechanical coupling effect and grain size effect are considered. The precipitate-dependent SE, eCE, one-way SME (OWSME), and stress-assisted two-way SME (SATWSME) of single-crystal, polycrystalline, and gradient-nanograined NiTi SMAs are simulated. The effects of the precipitate density, grain orientation range (texture), and gradient-distributed precipitate are examined, and the underlying microscopic mechanisms are revealed. The simulation results and new findings not only contribute to a more comprehensive insight into the effect of Ni 4 Ti 3 precipitates on the MT, martensite reorientation, and functional properties of NiTi SMAs but also provide a reference for the development of excellent SMA-based solid refrigerants or SMA smart materials with designable functional properties. [ABSTRACT FROM AUTHOR]

Insufficient autophagy subsequently promotes adipogenic differentiation, inhibits osteogenic differentiation of BMMSCs, and ultimately leads to bone mass loss. shHDAC9 treatment could partially rescue the impaired osteogenic differentiation of aged endogenous BMMSCs and restore bone mass. In young BMMSCs, the low expression level of HDAC9 maintains the high levels of acetylation modifications on H3K9 of autophagy-related genes which promotes intracellular autophagosomes formation, and subsequently facilitates osteogenic differentiation of BMMSCs. [Extracted from the article]

Apoptosis is a naturally occurring process generating plenty of apoptotic vesicles (apoVs), but the feature, fate and function of apoVs remain largely unknown. Notably, as an appealing source for cell therapy, mesenchymal stem cells (MSCs) undergo necessary apoptosis and release apoVs during therapeutic application. In this study, we characterized and used MSC‐derived apoVs to treat type 2 diabetes (T2D) mice, and we found that apoVs were efferocytosed by macrophages and functionally modulated liver macrophage homeostasis to counteract T2D. We showed that apoVs can induce macrophage reprogramming at the transcription level in an efferocytosis‐dependent manner, leading to inhibition of macrophage accumulation and transformation of macrophages towards an anti‐inflammation phenotype in T2D liver. At the molecular level, we discovered that calreticulin (CRT) was exposed on the surface of apoVs to act as a critical 'eat‐me' signal mediating apoV efferocytosis and macrophage regulatory effects. Importantly, we demonstrated that CRT‐mediated efferocytosis of MSC‐derived apoVs contributes to T2D therapy with alleviation of T2D phenotypes including glucose intolerance and insulin resistance. These findings uncover that functional efferocytosis of apoVs restores liver macrophage homeostasis and ameliorates T2D. [ABSTRACT FROM AUTHOR]

Background: Bone mass loss in aging is linked with imbalanced lineage differentiation of bone marrow mesenchymal stem cells (BMMSCs). Recent studies have proved that histone deacetylases (HDACs) are regarded as key regulators of bone remodeling. However, HDACs involve in regulating BMMSC bio-behaviors remain elusive. Here, we investigated the ability of HDAC9 on modulation of autophagy and its significance in lineage differentiation of BMMSCs. Methods: The effects of HDAC9 on lineage differentiation of BMMSCs and autophagic signaling were assessed by various biochemical (western blot and ChIP assay), morphological (TEM and confocal microscopy), and micro-CT assays. Results: Sixteen-month mice manifested obvious bone mass loss and marrow fat increase, accompanied with decreased osteogenic differentiation and increased adipogenic differentiation of BMMSCs. Further, the expression of HDAC9 elevated in bone and BMMSCs. Importantly, HDAC9 inhibitors recovered the lineage differentiation abnormality of 16-month BMMSCs and reduced p53 expression. Mechanistically, we revealed that HDAC9 regulated the autophagy of BMMSCs by controlling H3K9 acetylation in the promoters of the autophagic genes, ATG7, BECN1, and LC3a/b, which subsequently affected their lineage differentiation. Finally, HDAC9 inhibition improved endogenous BMMSC properties and promoted the bone mass recovery of 16-month mice. Conclusions: Our data demonstrate that HDAC9 is a key regulator in a variety of bone mass by regulating autophagic activity in BMMSCs and thus a potential target of age-related bone loss treatment. [ABSTRACT FROM AUTHOR]

The coastline is the dividing line between the ocean and land. Monitoring coastline dynamics is of crucial importance because it provides essential information for understanding the coastal response to contemporary climate change and human impacts. Real-time monitoring of coastlines has increasingly depended on remote sensing images at high temporal and spatial resolutions. In this study, a method combining the tasseled cap transformation (TCT) and feature knowledge is proposed to extract coastline information. Because traditional remote sensing methods cannot be used where total suspended sediment content is high, land and ocean separation was carried out using the wetness component of the Otsu method. A mathematical morphology analysis was used to remove the influence of lakes, rivers, and ships. Coastlines with shorter length were eliminated, and intermittent coastlines were connected based on a coordinate geometry description (such as length, distance, and direction). For the period of 2000–2018, Landsat-5 TM (Thematic Mapper) and Landsat-8 OLI (Operational Land Imager) images of the Zhoushan Islands, China, were used to extract coastline information using a method combining TCT and feature knowledge. A comparison of the results with reference data obtained by visual interpretation shows that the average of producer accuracy and user accuracy are 93.62% and 96.15%, respectively, and the average of length error was 2.45%. Therefore, the proposed method was effective in delineating the boundary between land and ocean and more effective than traditional methods in areas with high suspended sediment concentrations. [ABSTRACT FROM AUTHOR]

The effective retention of anaerobic ammonia oxidizing (anammox) bacteria and its high sensitivity to toxic substances and oxygen posed a major challenge to the application of partial nitrification combined with anammox (PN/A) in mature landfill leachate treatment, although it is a promising and efficient nitrogen removal process. In this study, a single-stage PN/A process based on expanded granular sludge bed was proposed to treat the mature landfill leachate. During the last phase, when the NH+ 4-N concentration of mature landfill leachate in influent was 1150.0 mg/L, the nitrogen removal efficiency (NRE) was 83.64% with 1.07 kg N/(m3·d) nitrogen removal rate (NRR). The activity of anammox bacteria (AnAOB) and ammonia oxidizing bacteria (AOB) was 9.21 ± 0.22 mg N/(gVSS·h) and 14.34 ± 0.65 mg N/(gVSS·h), respectively. The bacteria produced a high amount of tightly bound extracellular polymeric substance (TB-EPS) i.e., 4071.79 mg/(g·VSS). This helped to create granular sludge and provided favorable spatial conditions for the distribution of functional bacteria that were adapted to different environments. Due to the efficient retention of functional bacteria by the granular sludge, the relative abundance of Ca.Brocadia and Ca.Kuneneia was 1.71% and 0.31%, respectively. Redundancy analysis (RDA) and microbial correlation network diagram showed that the relative abundance of Ca. Kuenenia , Nitrosomonas and Truepera had a stronger positive correlation with the increase of the proportion of mature landfill leachate added to the influent. Overall, the PN/A process based on granular sludge provides an effective method for autotrophic biological nitrogen removal from mature landfill leachate. [Display omitted] • Mature landfill leachate was treated via one-stage AOB-AnAOB granular sludge. • Ca. Jettenia has shown strong tolerance to mature landfill leachate. • TIN removal efficiency of 83.64% was achieved when NLR was 1.23 kg N/(m3·d). [ABSTRACT FROM AUTHOR]

Our work describes the accuracy of Chinese quad-polarization Gaofen-3 (GF-3) synthetic aperture radar (SAR) wave mode data for wave retrieval and provides guidance for the operational applications of GF-3 SAR. In this study, we evaluated the accuracy of the SAR-derived significant wave height (SWH) from 10,514 GF-3 SAR images with visible wave streaks acquired in wave mode by using the existing wave retrieval algorithms, e.g., the theoretical-based algorithm parameterized first-guess spectrum method (PFSM), the empirical algorithm CSAR_WAVE2 for VV-polarization, and the algorithm for quad-polarization (Q-P). The retrieved SWHs were compared with the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis field with 0.125° grids. The root mean square error (RMSE) of the SWH is 0.57 m, found using CSAR_WAVE2, and this RMSE value was less than the RMSE values for the analysis results achieved with the PFSM and Q-P algorithms. The statistical analysis also indicated that wind speed had little impact on the bias with increasing wind speed. However, the retrieval tended to overestimate when the SWH was smaller than 2.5 m and underestimate with an increasing SWH. This behavior provides a perspective of the improvement needed for the SWH retrieval algorithm using the GF-3 SAR acquired in wave mode. [ABSTRACT FROM AUTHOR]