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Femtosecond laser direct writing is a powerful technique for fabricating micro‐nano devices as it can modify the interior of transparent optical materials in a spatially selective manner through nonlinear multi‐photon absorption. In this context, laser‐induced nanogratings, i.e., a sub‐wavelength assembly of nanolayers (≈20 nm in width, ≈200 nm period), are ultrashort self‐organized structures created by light in the bulk of transparent materials. These have been intensively explored over the last two decades opening a novel era of micro photonic devices due to their unique physicochemical properties, like orientable form birefringence, anisotropic light scattering, highly selective chemical etching, optical chirality, and extraordinary thermal stability. This review provides a throughout overview of the advances in this field, specifically focused on the formation of nanogratings, optical properties that can be exploited in various transparent solids, and the related main applications. Also, the fundamental characteristics, formation mechanism, tuning methods of nanogratings are reviewed. [ABSTRACT FROM AUTHOR]

To investigate the molecular mechanism of the defense response of "Cabernet Sauvignon" grapes to feeding by Apolygus lucorum, high‐throughput sequencing technology was used to analyze the transcriptome of grape leaves under three different treatments: feeding by A. lucorum, puncture injury, and an untreated control. The research findings indicated that the differentially expressed genes were primarily enriched in three aspects: cellular composition, molecular function, and biological process. These genes were found to be involved in 42 metabolic pathways, particularly in plant hormone signaling metabolism, plant‐pathogen interaction, MAPK signaling pathway, and other metabolic pathways associated with plant‐induced insect resistance. Feeding by A. lucorum stimulated and upregulated a significant number of genes related to jasmonic acid and calcium ion pathways, suggesting their crucial role in the defense molecular mechanism of "Cabernet Sauvignon" grapes. The consistency between the gene expression and transcriptome sequencing results further supports these findings. This study provides a reference for the further exploration of the defense response in "Cabernet Sauvignon" grapes by elucidating the expression of relevant genes during feeding by A. lucorum. [ABSTRACT FROM AUTHOR]

In the natural ecosystem, plants usually grow at high vegetation density for yield maximization. The high‐density planting triggers a variety of strategies to avoid canopy shade and competes with their neighbors for light and nutrition, which are collected termed shade avoidance responses. The molecular mechanism underlying shade avoidance and nutrition has expanded largely in the past decade; however, how these two responses intersect remains poorly understood. Here, we show that simulated shade undermined Pi starvation response and the phytohormone JA is involved in this process. We found that the JA signaling repressor JAZ proteins directly interact with PHR1 to repress its transcriptional activity on downstream targets, including phosphate starvation induced genes. Furthermore, FHY3 and FAR1, the negative regulators of shade avoidance, directly bind to promoters of NIGT1.1 and NIGT1.2 to activate their expression, and this process is also antagonized by JAZ proteins. All these results finally result in attenuation of Pi starvation response under shade and Pi‐depleted conditions. Our findings unveil a previously unrecognized molecular framework whereby plants integrate light and hormone signaling to modulate phosphate responses under plant competition. [ABSTRACT FROM AUTHOR]

Background and Aims: Human bone marrow mesenchymal stem cells (hBMSCs) are important for developing a dual‐humanized mouse model to clarify disease pathogenesis. We aimed to elucidate the characteristics of hBMSC transdifferentiation into liver and immune cells. Methods: A single type of hBMSCs was transplanted into immunodeficient Fah−/− Rag2−/− IL‐2Rγc−/− SCID (FRGS) mice with fulminant hepatic failure (FHF). Liver transcriptional data from the hBMSC‐transplanted mice were analysed to identify transdifferentiation with traces of liver and immune chimerism. Results: Mice with FHF were rescued by implanted hBMSCs. Human albumin/leukocyte antigen (HLA) and CD45/HLA double‐positive hepatocytes and immune cells were observed in the rescued mice during the initial 3 days. The transcriptomics analysis of liver tissues from dual‐humanized mice identified two transdifferentiation phases (cellular proliferation at 1–5 days and cellular differentiation/maturation at 5–14 days) and ten cell lineages transdifferentiated from hBMSCs: human hepatocytes, cholangiocytes, stellate cells, myofibroblasts, endothelial cells and immune cells (T/B/NK/NKT/Kupffer cells). Two biological processes, hepatic metabolism and liver regeneration, were characterized in the first phase, and two additional biological processes, immune cell growth and extracellular matrix (ECM) regulation, were observed in the second phase. Immunohistochemistry verified that the ten hBMSC‐derived liver and immune cells were present in the livers of dual‐humanized mice. Conclusions: A syngeneic liver‐immune dual‐humanized mouse model was developed by transplanting a single type of hBMSC. Four biological processes linked to the transdifferentiation and biological functions of ten human liver and immune cell lineages were identified, which may help to elucidate the molecular basis of this dual‐humanized mouse model for further clarifying disease pathogenesis. [ABSTRACT FROM AUTHOR]

Hepatitis B virus‐related acute‐on‐chronic liver failure (HBV‐ACLF) is a syndrome with high short‐term mortality. The mechanism of the transcription factor ETS2 in ACLF remains unclear. This study aimed to clarify the molecular basis of ETS2 in ACLF pathogenesis. Peripheral blood mononuclear cells from patients with HBV‐ACLF (n = 50) were subjected to RNA sequencing. Transcriptome analysis showed that ETS2 expression was significantly higher in ACLF patients than in patients with chronic liver diseases and healthy subjects (all p < 0.001). Area‐under‐ROC analysis of ETS2 demonstrated high values for the prediction of 28‐/90‐day mortality in ACLF patients (0.908/0.773). Significantly upregulated signatures of the innate immune response (monocytes/neutrophils/inflammation‐related pathways) were observed in ACLF patients with high ETS2 expression. Myeloid‐specific ETS2 deficiency in liver failure mice resulted in deterioration of biofunctions and increased expression of pro‐inflammatory cytokines (IL‐6/IL‐1β/TNF‐α). Knockout of ETS2 in macrophages confirmed the downregulation of IL‐6 and IL‐1β caused by both HMGB1 and lipopolysaccharide, and an NF‐κB inhibitor reversed the suppressive effect of ETS2. ETS2 is a potential prognostic biomarker of ACLF patients that alleviates liver failure by downregulating the HMGB1‐/lipopolysaccharide‐triggered inflammatory response and may serve as a therapeutic target for ACLF. [ABSTRACT FROM AUTHOR]

Vascularization is a critical but challenging process in developing functional bioengineered livers with the decellularized liver scaffolds (DLSs) and the process is accompanied by cell‐specific metabolic alterations. To elucidate the dynamic alterations of metabolites during vascularization, rat DLSs were vascularized with human umbilical vein endothelial cells and liquid chromatography mass spectrometry‐based metabolomics was performed on culture supernatants collected at 0, 1, 3, 7, 14, and 21 days. Overall, 1698 peak pairs or metabolites were detected in the culture supernatants, with 309 metabolites being positively identified. The orthogonal partial least‐squares discriminant analysis and functional enrichment analysis revealed three phases that could be clearly discriminated, including Phase D1 (cell proliferation and migration), Phase D3D7 (vascular lumen formation), and Phase D14D21 (functional endothelial barrier formation). Seventy‐two common differentially abundant metabolites of known identity were detected in these three phases when compared with Day 0. Of these metabolites, a high level of β‐Alanine indicated a better degree of vascularization and 14 days of in vitro dynamic culture is required to develop a functionalized vascular structure. These results enriched our understanding of the metabolic mechanism of DLS vascularization and indicated that β‐Alanine could function as a potential predictor of the patency of vascularized bioengineered livers. [ABSTRACT FROM AUTHOR]

Antimony (Sb) is a toxic heavy metal, and PM2.5‐bound Sb (SbPM2.5) in the air impacts human health via inhalation pathways. In this study, we analyzed multiyear measurements of ambient SbPM2.5 in Beijing to characterize its spatiotemporal distributions, identify main sources, and predict future trends. The results show that ambient SbPM2.5 has been decreasing with fluctuations from 2005 to 2012 and decreased rapidly after 2013, which was likely a result of the government's enhanced air pollution control plan that targeted main sources of industrial Sb. Across the city, average SbPM2.5 concentrations were relatively higher at nonemission locomotive traffic sampling sites and in densely populated areas (9.45–19.45 ng/m3) and lower in background areas (0.6–0.9 ng/m3). Regional‐scale emissions and local human activities both affected the spatial distributions of SbPM2.5. Notably, SbPM2.5 concentration increased by 58.3% from 2006 to 2013 in one suburban background area, indicating the changing emission distributions and intensities over the study period. A neural network model was developed and tested to predict future SbPM2.5 levels, results from which showed that with simulated massive reductions in coal supplies and a rapid boom in the waste incineration industry, SbPM2.5 concentration would vary in a smaller range (from 4.08 to 4.38 ng/m3) over the next decade as compared to the observed range during 2011–2018 (19.0–5.44 ng/m3). The impact of the continued expansion of the waste incineration industry on SbPM2.5 pollution needs to be considered in future emission control policies. Plain Language Summary: Long‐term exposure to antimony (Sb) and related compounds, such as through respiration of Sb containing atmospheric particles, can result in negative health impacts to human body. Knowledge of concentration levels and future trends of Sb in PM2.5 (SbPM2.5) especially in populated megacities is needed in assessing the potential risks of atmospheric Sb to human health. In this study, SbPM2.5 concentration data in Beijing over the past 15 years were aggregated to assess its past trends and predict its future levels. Benefited from the implementation of stringent air pollution control programs in this region, SbPM2.5 concentrations have been decreasing, but with fluctuations from 2005 to 2012, and at a faster rate after 2013. However, the decreasing trend will likely slowdown in the next decade due to the rapid development of the waste‐to‐energy conversion industry, which is an important source of atmospheric SbPM2.5 emission. Thus, future SbPM2.5 levels may still pose a threat to human health, especially to infants and children. Key Points: Characteristics of PM2.5‐bound antimony in Beijing have been summarized over 15 years and they predict future trendsThe aggressive reduction of antimony (Sb) pollution levels is mainly influenced by a comprehensive air pollution control program by the governmentThe Sb emissions from waste incineration are likely to replace coal combustion as the primary source in PM2.5 now and in the next decade [ABSTRACT FROM AUTHOR]

Since Joint Photographic Experts Group is a typical image compression standard, so the reversible data hiding research on Joint Photographic Experts Group has received a lot of attention. There are two main research methods in Joint Photographic Experts Group‐reversible data hiding: the method based on modifying DCT coefficients and the method based on variable length coding mapping. The disadvantage of the first one is that the visual loss is always inevitable during the DCT‐coefficient modification process, while the second method often has insufficient embedding capacity and excessive file expansion. In order to solve the above problems, this paper proposes a cascaded reversible data hiding scheme, which builds a distortion minimisation scheme based on the DCT coefficients, and then cascades a file expansion suppression scheme based on the variable length coding mapping. For a particular case during the payload distribution, in this paper, all the secret information is embedded into DCT coefficients with a distortion minimisation scheme, and then the auxiliary information generated in the previous process is embedded in the variable length coding sequence with a scheme to optimise the file size expansion. The experimental results demonstrate the superiority of the proposed method in high‐quality factor circumstances in terms of visual quality and file expansion. [ABSTRACT FROM AUTHOR]

BACKGROUND: 'Gold Finger' is a grape cultivar with a finger‐like shape and a milk flavor. The process by which its aroma profile evolves during ripening is unclear. Thus, changes in the free and bound volatile compounds present in 'Gold Finger' grapes during ripening were investigated using headspace sampling–solid‐phase microextraction–gas chromatography–mass spectroscopy (HS‐SPME‐GC‐MS). RESULTS: A total of 83 volatile aroma components were identified in the grapes, with aldehydes, esters, acids, and alcohols being the main components. The total aroma compound content exhibited significant differences between the bound and free forms. The total content of bound volatile compounds did not change significantly during fruit development, although the free aroma compound content was significantly higher than the bound content. The total content of free aldehydes, free alcohols, bound norisoprenoids, and ketones gradually increased for up to 70 days after flowering (DAF), while the total free ester, terpene, and acid content decreased. The characteristic aroma compounds of 'Gold Finger' grapes were identified as hexanal, (E)‐2‐hexenal, and ethyl hexanoate. CONCLUSIONS: These results give a foundation for the further development of 'Gold Finger' grapes and provide a theoretical basis for the selection and breeding of novel aromatic grape varieties. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae, budding yeast, is a widely used model organism and research tool in genetics studies. Many efforts have been directed at constructing a high‐quality comprehensive molecular interaction network to elucidate the design logic of the gene circuitries in this classic model organism. In this work, we present the yeast interactome resource (YIR), which includes 22,238 putative functional gene interactions inferred from functional gene association data integrated from 10 databases focusing on diverse functional perspectives. These putative functional gene interactions are expected to cover 18.84% of yeast protein interactions, and 38.49% may represent protein interactions. Based on the YIR, a gene set linkage analysis (GSLA) web tool was developed to annotate the potential functional impacts of a set of transcriptionally changed genes. In a case study, we show that the YIR/GSLA system produced more extensive and concise annotations compared with widely used gene set annotation tools, including PANTHER and DAVID. Both YIR and GSLA are accessible through the website http://yeast.biomedtzc.cn. [ABSTRACT FROM AUTHOR]

Aim: The artificial liver support system (ALSS) is recognized as a bridge to liver transplantation in hepatitis B virus‐related acute‐on‐chronic liver failure (HBV‐ACLF) patients. However, patient survival remains unknown. We aim to assess the effects of ALSS on survival in HBV‐ACLF patients. Methods: The clinical data of HBV‐ACLF patients receiving standard medical treatment (SMT) plus ALSS (ALSS group, n = 507) or only SMT (SMT group, n = 417) were collected for survival assessment. The main end‐points were cumulative survival rates at days 21, 28, and 90. Four different rigorous analyses were carried out to reduce bias and confounding. Results: In the entire cohort, the cumulative survival rates at days 21, 28, and 90 were significantly higher in patients who underwent ALSS treatment (73.3% vs. 59.6%, 69.2% vs. 56.6%, 56.5% vs. 49.1%, respectively, P < 0.01) than in those who underwent SMT only. In the 276‐pair case–control matched cohort, a significantly higher survival rate was also observed in the ALSS group than in the SMT group on days 21, 28, and 90 (72.5% vs. 60.3%, 68.3% vs. 57.4%, 55.9% vs. 48.5%, respectively, P < 0.05), especially in patients with ACLF‐1 and ‐2. By a multivariable‐adjusted analysis, ALSS treatment was associated with a significantly lower risk of mortality, especially for ACLF‐2 at days 21, 28, and 90. These findings were also confirmed through propensity score matching and inverse probability treatment weighting analysis. Conclusions: ALSS treatment can improve short‐term survival and is associated with a significantly lower risk of short‐term mortality in patients with HBV‐ACLF, especially ACLF‐2. [ABSTRACT FROM AUTHOR]

The precise estimation of the noise level is a crucial issue in image processing. In this study, the authors propose a new method for noise standard deviation (STD) estimation from natural images based on skewness‐scale invariance in the transform domain and an adaptive noise injection strategy. The method is divided into two steps. The first step assumes that the natural clean image has the property of constancy of skewness in the transform domain. Then, a preliminary noise estimation method based on skewness invariance is designed by solving a constrained non‐linear optimisation problem. The second step involves noise rectification via noise injection. According to the phenomenon that compared with the high‐noise circumstance, the error of preliminary estimation is more serious under a low amount of noise, the noise STD is re‐estimated by injecting another noise for which the STD is known. In addition, the threshold model with respect to image complexity is established to identify whether a second estimation is needed. The experimental results demonstrate the efficacy of the proposed method and performance is superior to other state‐of‐the‐art methods. [ABSTRACT FROM AUTHOR]

To understand the impacts of organic matter on the geochemical processing of Hg in a hydroelectric reservoir, spatial and seasonal distributions of total mercury (THg) and methylmercury (MeHg) in both solid and liquid phases of sediment cores were investigated in the Wujiangdu Reservoir in Guizhou Province, China. Four sampling sites with different intensities of cage aquaculture activities were chosen and were evenly distributed from upstream to downstream of the Wujiangdu Reservoir. Elevated MeHg concentrations and the high percentage of MeHg in solid and liquid phases of the surface sediment demonstrated that the active Hg methylation process occurred downstream of the Wujiangdu Reservoir. In contrast, the absence of obvious peaks for MeHg in sediment from the upper reaches of the Wujiangdu Reservoir, consistent with low levels of organic matter, suggested that production of MeHg was limited. In sediment with high organic matter content, reduction occurred closer to the sediment surface, resulting in maximum MeHg concentration in these layers. The correlation between MeHg and organic carbon implied that organic matter content in the sediment originating from cage aquaculture activities can help to predict MeHg production rates in reservoirs, which could be used to assess possible MeHg contamination in a reservoir ecosystem. [ABSTRACT FROM AUTHOR]

To assess adequately the impact of methylmercury (MeHg) on sensitive wetland ecosystems, accurate measurements of MeHg in pore water are required. In the present study, the feasibility of three methods for porewater sampling was investigated with respect to MeHg in sediments and rice paddy fields. The performance of dialysis samplers (peepers), sediment core sectioning followed by porewater separation by centrifugation (core), and the thin film diffusive samplers (DGT) were evaluated. These methods were intercompared in field experiments at two sites in Guizhou province, SW China disparately impacted by mercury pollution. All the methods report that the concentrations of MeHg in the soils of the Gouxi (GX) rice paddy near Wanshan were much higher than that in the sediment of the Hongjiadu Reservoir (HR), which is located within the Wujiang River basin. The three methods also report different MeHg profiles at the same site. However, these methods exhibit different temporal and spatial resolution scales, due to the differing operations involved with the sampling methods, may also reflect different states of MeHg in pore water. This corresponds to MeHg derived from diffusive flux, equilibrium concentration, and bulk concentration in pore water detected by DGT, peeper, and sediment core, respectively. The advantages and limits of the three methods are also presented [ABSTRACT FROM AUTHOR]

Due to the massive monitored samples and their features such as strong coupling and time delay in large‐scale industrial process, the decentralized monitoring methods, which divide the variables into several blocks and perform local monitoring in each subblock, have been brought up to handle the complex characteristics. However, most of the existing decentralized methods utilize the correlation degree among variables for block division, while the correlation patterns among variables are ignored. The missing of correlation pattern will influence the monitoring performance. To address this problem, the copula‐correlation analysis, which considers both the correlation degree and the correlation pattern, is adopted for block division; then the principal component analysis (PCA)–based method is used for subblock monitoring, and the Bayesian inference is introduced to achieve decision fusion of fault detection. The superiority and effectiveness of the proposed method are illustrated through comparison studies on a numerical example and the Tennessee Eastman (TE) benchmark process. Copula‐correlation analysis, which considers the correlation degree and correlation pattern simultaneously, is adopted for block division.PCA‐based method is used for subblock monitoring.Bayesian inference is introduced to achieve decision fusion of fault detection. [ABSTRACT FROM AUTHOR]