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Simple Summary: Trachycarpus nanus is a national, second-class, rare and endangered plant in China, and a plant species endemic to Yunnan. This species has a high medicinal, ecological, and scientific value, but it is currently on the verge of extinction. Therefore, it is urgent to learn its extinction risk under global warming. We predict its multi-temporal distribution pattern based on the optimized MaxEnt model. The results show that precipitation is the most important factor. In the future, drastic climatic changes and human disturbances may lead to the extinction of this species, so it is necessary to strengthen the protection of this species using specific strategies. Climate change affects the geographical distribution of plant species. Rare Trachycarpus nanus with a narrow distribution range, high medicinal value and extremely small population is facing increasing extinction risks under global climate change. In this study, 96 recorded occurrences and 23 environmental factors are used to predict the potential suitable area of T. nanus based on the optimized MaxEnt (3.4.4) model and ArcGIS (10.7) software. The results show that when the parameters are FC = LQ and RM = 1, the MaxEnt model is optimal and AUC = 0.946. The distribution patterns were predicted in the past, present, and four future phases, i.e., 2021–2040 (2030), 2041–2060 (2050), 2061–2080 (2070), and 2081–2100 (2090). The main factors are the annual precipitation (bio12), mean temperature of the coldest quarter (bio11), temperature seasonality (bio4), precipitation of the wettest quarter (bio16), and isothermality (bio3). The potential distribution of T. nanus is primarily concentrated in central Chuxiong, encompassing a total potential suitable area of 5.65 × 104 km2. In historical periods, the total habitat area is smaller than that in the present. In the future, the potential suitable area is generally increased. The centroid analysis shows that T. nanus will move to a high-altitude area and to the southeast. But its dispersal capacity may not keep up with the climate change rate. Therefore, additional protection sites for this species should be appropriately established and the habitat connectivity should be enhanced. [ABSTRACT FROM AUTHOR]

This paper addressed the rockburst hazards caused by tectonic stress in the "three hard" coal mine in Datong Coalfield. We analyzed tectonic stress characteristics in the mining area and the mechanism of tectonic stress inducing rockbursts. We built the stress analysis model for rockburst-inducing tectonic stress. The roadway of the coal seam 12# in Xinzhouyao Coal Mine of Datong Coalfield was explicitly analyzed as an example. It was found that roof bedding separation was very likely to happen under the action of local tectonic stress in the roadway of the "three hard" coal seam, causing rockbursts that pushed out the coal wall. Numerical simulation was performed to analyze the occurrence of rockbursts induced by tectonic stress. We validated that stress concentration was more likely to happen in the coal-rock masses under the action of the tectonic stress, causing rockbursts. Besides, a large horizontal stress gradient would be formed near the roadway coal wall when the principal stress was perpendicular to the roadway axis. Rockbursts were highly probable in the coal-rock masses under this situation. [ABSTRACT FROM AUTHOR]

Investigating the spatiotemporal variation characteristics of aerosol optical depth (AOD) and its driving factors is essential for assessing atmospheric environmental quality and alleviating air pollution. Based on a 22-year high-resolution AOD dataset, the spatiotemporal variations of AOD in mainland China and ten national urban agglomerations were explored based on the Mann–Kendall trend test and Theil–Sen median method. Random forest (RF) and multiscale geographically weighted regression (MGWR) were combined to identify the main driving factors of AOD in urban agglomerations and to reveal the spatial heterogeneity of influencing factors. The results showed that areas with high annual average AOD concentrations were mainly concentrated in the Chengdu–Chongqing, Central Plains, Shandong Peninsula, and Middle Yangtze River urban agglomerations. Southern Beijing–Tianjin–Hebei and its surrounding areas revealed the highest AOD pollution during summer, whereas the worst pollution during the remaining three seasons occurred in the Chengdu–Chongqing urban agglomeration. Temporally, except for the Ha-Chang and Mid-Southern Liaoning urban agglomerations, where the average annual AOD increased, the other urban agglomerations showed a decreasing trend. Among them, the Central Plains, Middle Yangtze River, Guanzhong Plain, and Yangtze River Delta urban agglomerations all exhibited a decline greater than 20%. According to the spatial trends, most urban agglomerations encompassed much larger areas of decreasing AOD values than areas of increasing AOD values, indicating that the air quality in most areas has recently improved. RF analysis revealed that PM2.5 was the dominant factor in most urban clusters, followed by meteorological factors. MGWR results show that the influencing factors have different spatial scale effects on AOD in urban agglomerations. The socioeconomic factors and PM2.5 showed strong spatial non-stationarity with regard to the spatial distribution of AOD. This study can provide a comprehensive understanding of AOD differences among urban agglomerations, and it has important theoretical and practical implications for improving the ecological environment and promoting sustainable development. [ABSTRACT FROM AUTHOR]

Diabetes mellitus represents a significant global health threat characterized by hyperglycemia caused by inadequate insulin secretion and/or insulin resistance. Exogenous insulin supplements had been recognized as a crucial treatment for achieving successful glycemic control in patients with Type 1 and most patients with Type 2 diabetes. Over the past century, substantial progress has been made in the development of novel insulin formulations, including the super‐fast‐acting and long‐acting basal insulin analogs, of which the latter is indispensable for the management of nocturnal fasting and intraprandial blood glucose within the normal physiological range. Recently, combining chemical and genetic engineering with drug optimization have resulted in a formidable evolution in ultra‐long‐acting weekly insulin. Here, the current state of once‐weekly insulin analogs and the euglycemic clamp technique used in the early clinical development to elucidate the pharmacokinetics and pharmacodynamics of this type of novel weekly insulin analogs were systematically overviewed. [ABSTRACT FROM AUTHOR]

The novel concept of local climate zones (LCZs) provides a consistent classification framework for studies of the urban thermal environment. However, the development of urban climate science is severely hampered by the lack of high-resolution data to map LCZs. Using Gaofen-6 and Sentinel-1/2 as data sources, this study designed four schemes using convolutional neural network (CNN) and random forest (RF) classifiers, respectively, to demonstrate the potential of high-resolution images in LCZ mapping and evaluate the optimal combination of different data sources and classifiers. The results showed that the combination of GF-6 and CNN (S3) was considered the best LCZ classification scheme for urban areas, with OA and kappa coefficients of 85.9% and 0.842, respectively. The accuracy of urban building categories is above 80%, and the F1 score for each category is the highest, except for LCZ1 and LCZ5, where there is a small amount of confusion. The Sentinel-1/2-based RF classifier (S2) was second only to S3 and superior to the combination of GF-6 and random forest (S1), with OA and kappa coefficients of 64.4% and 0.612, respectively. The Sentinel-1/2 and CNN (S4) combination has the worst classification result, with an OA of only 39.9%. The LCZ classification map based on S3 shows that the urban building categories in Xi'an are mainly distributed within the second ring, while heavy industrial buildings have started to appear in the third ring. The urban periphery is mainly vegetated and bare land. In conclusion, CNN has the best application effect in the LCZ mapping task of high-resolution remote sensing images. In contrast, the random forest algorithm has better robustness in the band-abundant Sentinel data. [ABSTRACT FROM AUTHOR]

Accurate identification of the miRNA-disease associations (MDAs) helps to understand the etiology and mechanisms of various diseases. However, the experimental methods are costly and time-consuming. Thus, it is urgent to develop computational methods towards the prediction of MDAs. Based on the graph theory, the MDA prediction is regarded as a node classification task in the present study. To solve this task, we propose a novel method MDA-GCNFTG, which predicts MDAs based on Graph Convolutional Networks (GCNs) via graph sampling through the Feature and Topology Graph to improve the training efficiency and accuracy. This method models both the potential connections of feature space and the structural relationships of MDA data. The nodes of the graphs are represented by the disease semantic similarity, miRNA functional similarity and Gaussian interaction profile kernel similarity. Moreover, we considered six tasks simultaneously on the MDA prediction problem at the first time, which ensure that under both balanced and unbalanced sample distribution, MDA-GCNFTG can predict not only new MDAs but also new diseases without known related miRNAs and new miRNAs without known related diseases. The results of 5-fold cross-validation show that the MDA-GCNFTG method has achieved satisfactory performance on all six tasks and is significantly superior to the classic machine learning methods and the state-of-the-art MDA prediction methods. Moreover, the effectiveness of GCNs via the graph sampling strategy and the feature and topology graph in MDA-GCNFTG has also been demonstrated. More importantly, case studies for two diseases and three miRNAs are conducted and achieved satisfactory performance. [ABSTRACT FROM AUTHOR]

Nowadays, graph-structured data are increasingly used to model complex systems. Meanwhile, detecting anomalies from graph has become a vital research problem of pressing societal concerns. Anomaly detection is an unsupervised learning task of identifying rare data that differ from the majority. As one of the dominant anomaly detection algorithms, one-class support vector machine has been widely used to detect outliers. However, those traditional anomaly detection methods lost their effectiveness in graph data. Since traditional anomaly detection methods are stable, robust and easy to use, it is vitally important to generalize them to graph data. In this work, we propose one-class graph neural network (OCGNN), a one-class classification framework for graph anomaly detection. OCGNN is designed to combine the powerful representation ability of graph neural networks along with the classical one-class objective. Compared with other baselines, OCGNN achieves significant improvements in extensive experiments. [ABSTRACT FROM AUTHOR]

Electrochemical nitrogen fixation has received great attention in recent years due to its reliable and stable electrolytic efficiency. In this work, boron-doped carbon nitride with π-electron delocalization and vacancies was prepared by an in situ decomposition-thermal polymerization method. A series of characterizations were utilized to analyze the structure, morphology, and property. The results demonstrated that the secondary sintering and boron doping enhanced π-electron delocalization and induced the nitrogen vacancies of g-C3N4. The 0.24% boron-doped g-C3N4 electrocatalyst achieved the best ammonia yield (5.4 μg·h−1·mgcat−1) and the highest Faraday efficiency (14.1%) at −0.7 V vs reversible hydrogen electrode in 0.1 M Na2SO4. Furthermore, a feasible mechanism was proposed for the electrochemical nitrogen reduction process. [ABSTRACT FROM AUTHOR]

Small CoTiO 3 nanoparticles were embedded in TiO 2 nanoshells to boost peroxymonosulfate (PMS) activation and enhance 4-chlorophenol (4-CP) degradation due to the enhanced mass transfer in the confined space, and efficient electron transfer between PMS and TiO 2 /CoTiO 3. [Display omitted] Creating a microenvironment for enhanced peroxymonosulfate (PMS) activation is vital in advanced oxidation processes. The objective of this study was to fabricate nanoshells composed of titanium dioxide embedded with cobalt titanate nanoparticles of perovskite to act as nanoreactors for effectively initiating PMS and degrading contaminants. The unique porous structure and confined space of the nanoreactor facilitated reactant absorption and mass transfer to the active sites, resulting in exceptional catalytic performance for pollutant elimination. Experimental findings revealed close to 100% decomposition efficiency of 4-chlorophenol (4-CP) within an hour utilizing the nanoreactors over a wide pH range. The TiO 2 /CoTiO 3 hollow nanoshells catalysts also displayed adaptability in disintegrating organic dyes and antibiotics. The radicals SO 4 •-, •OH, and non-radicals 1O 2 were determined to be accountable for eliminating pollutants, as supported by trapping experiments and electron paramagnetic resonance spectra. The catalyst was confirmed as an electron donor and PMS as an electron acceptor through electrochemical tests and density functional theory calculations. This study underscores the potential of incorporating stable perovskite catalysts in hollow nanoreactors to enhance wastewater treatment. [ABSTRACT FROM AUTHOR]

In order to identify the disturbance signal in power system and reduce the influence on system security, a voltage disturbance signal classifier based on improved local mean decomposition (ILMD) and BP neural network is proposed. ILMD is used to decompose the disturbance signal in three layers, and the product function (PF) component with amplitude-frequency information of voltage signal is obtained. The signal energy value constructed by PF component is used as the input of BP neural network to identify and classify the voltage disturbance signal. Experiments on four typical voltage disturbance signals show that the signal classifiers based on ILMD and BP neural networks have high accuracy and good working efficiency for the recognition and classification of voltage disturbance signals. [ABSTRACT FROM AUTHOR]

Herein, in-situ Zr 3 [Al(Si)] 4 C 6 -based composites with 10–40 vol% ZrB 2 –SiC (2-to-1 molar ratio) were prepared by hot-pressing sintering at 1850 °C. The simultaneously incorporated ZrB 2 –SiC constitute multicomponent reinforcements and has a synergistic effect on the matrix, which improves the sinterability, mechanical properties, and oxidation resistance of materials. It is found that both of the toughness and strength increase first and then decrease with the increasing content of ZrB 2 –SiC, while the hardness increases near linearly. Zr 3 [Al(Si)] 4 C 6 –ZrB 2 –SiC shows high strength (623 MPa), toughness (7.59 MPa m1/2), and hardness (18.6 GPa), which can be ascribed to the synergistic mechanisms of the binary ZrB 2 –SiC including fine-grained strengthening, particle reinforcement, intragranular microstructure, grain's pull-out and crack bridging, etc. In addition, the oxidation kinetics of as-prepared materials follow the parabolic law, and the composite shows a low oxidation rate of 0.87 × 10−5 kg2 m−4 s−1 when oxidized at 1400 °C. [ABSTRACT FROM AUTHOR]

This paper presents a new variable-frequency phase-shift control method to improve the conversion efficiency for a high-power wide-range converter based on a phase-shifted full-bridge (PSFB) converter. The proposed converter can adjust the switching-frequency according to the load power to make the input impedance be inductive. The main switches of the converter can achieve zero voltage switching (ZVS) over a wide load range (500 W–50 kW) without any auxiliary circuit. The maximum switching-frequency of high-power insulated gate bipolar transistor (IGBT) is determined by analyzing the influence of collector current on IGBT switching time. The necessary condition for the proposed converter to realize ZVS is given according to the steady-state model of the full-bridge converter. This paper analyzed the influence of voltage, current and temperature on the switching time of high-power IGBT in detail, and obtained the relationship between the load current and the dead time of high-power IGBT. The optimal switching-frequency under different loads was determined by establishing a switching-frequency loss model of the proposed converter. A 50 kW prototype of the proposed converter was developed and the experimental and simulation results verify the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Pt-SnO 2 catalysts supported on modified carbon fibers were prepared by an electrospinning method with polyacrylonitrile (PAN) as the carrier and polyvinylidene fluoride (PVDF) as the pore-forming agent. The physical-chemical property and catalytic performance of the as-synthesized composites were characterized by XRD, SEM, BET, Chronoamperometry and AC impedance. The results showed that the porous structure in the carbon fibers was formed after calcination at 800 °C in the presence of PVDF. When the weight ratio of PAN/PVDF was 1:0.8, the porous carbon fibers had the largest surface area of 374.85 m2 g−1, which was 3.3 times of carbon fibers prepared without PVDF. The in-situ formed porous structure in carbon fibers can provide more active sites for the catalytic reaction. Therefore, the porous carbon fiber supported Pt-SnO 2 catalysts exhibited the best catalytic performance with the ethanol oxidation peak current value of 140.14 mA cm−2 and the electrochemical active area up to 54.296 m2 g−1. DEFC performance showed that the best potential was 0.7 V and the maximum of power density was 18.1 mW cm−2 when the oxygen flow rate and the temperature were 100 mL min−1 and 80 °C, respectively. Pt-SnO 2 catalysts supported on modified carbon fibers were prepared by an electrospinning method with polyacrylonitrile (PAN) as the carrier and polyvinylidene fluoride (PVDF) as the pore-forming agent. When the weight ratio of PAN/PVDF was 1:0.8, the porous carbon fibers had the largest surface area of 374.85 m2 g−1. The porous carbon fiber supported Pt-SnO 2 catalysts exhibited the best catalytic performance with the ethanol oxidation peak current value of 140.14 mA cm−2 and the electrochemical active area up to 54.296 m2 g−1. Image 1 • Porous carbon fibers were prepared by one-step electrospinning method. • PVDF was used as the pore-forming reagent during the carbonization process. • Porous C/Pt-SnO 2 exhibited the best catalytic activity for the ethanol oxidation. [ABSTRACT FROM AUTHOR]

Keratin 19 (KRT19) is a type I cytokeratin that serves an important role in multiple types of cancer; however, little is known regarding its role in thyroid cancer. Therefore, the aim of the current study was to investigate the role of KRT19 in thyroid cancer. Using The Cancer Genome Atlas database, the expression and clinical significance of KRT19 in thyroid cancer tissues were investigated. The effect of KRT19 in thyroid cancer cell lines was also investigated in vitro. The results demonstrated that KRT19 expression was higher in thyroid cancer when compared with normal thyroid tissues, and was associated with lymph node metastasis, tumor stage and tumor-node-metastasis stage. Knockdown of KRT19 inhibited the proliferation and migration of thyroid cancer cell lines. In addition, increased KRT19 expression was observed only in tumors harboring the B-Raf Proto-Oncogene, Serine/Threonine Kinase (BRAF)V600E mutation, and BRAFV600E overexpression induced KRT19 expression. Furthermore, KRT19 exerted its phenotype via promoting epithelial-mesenchymal transition (EMT). In conclusion, the results of the current study suggest that BRAFV600E-induced KRT19 expression may promote thyroid cancer metastasis via EMT. [ABSTRACT FROM AUTHOR]

To address the issue of white noise at partial discharge (PD) ultra high frequency (UHF) signal in gas insulated substation (GIS), this paper develops an external sensor and proposes new empirical mode decomposition (EMD) denoising method based on autocorrelation coefficient and similar wavelet soft threshold. Four types of typical GIS defects at the PD UHF signal were obtained through experiment. The autocorrelation coefficient of intrinsic mode functions (IMF) components at the PD UHF signal was computed, the cut-off point between the noise signal dominant mode and the UHF signal dominant mode was found. The similar wavelet soft threshold denoising was performed on the signal which is dominated by the noise signal, all the UHF signals were finally reconstructed. The signal-to-noise ratio computed by the proposed denoising method was compared with the one computed by the wavelet denoising method, the results shows that the proposed denoising method in this paper is more effective than the wavelet denoising method. [ABSTRACT FROM AUTHOR]

The spatio-temporal pattern of surface ecological status affects urban thermal environment distribution significantly. Urban thermal pattern, however, is a complicated physical phenomenon involving a series of terrestrial environmental parameters. Thus, it is insufficient to employ only one ecological parameter for depicting the variation of land surface temperature (LST). This paper begins with the analysis of four ecological parameters' influence on LST using regression analysis, based on 24 Landsat images which cover Xi'an of China from 1992 to 2014. These four parameters include greenness degree (i.e. the soil adjusted vegetation index, SAVI), soil moisture degree (i.e. the normalized difference moisture index, NDMI), dryness degree (i.e. the normalized difference soil index, NDSI) and resident aggregation degree (i.e. the normalized difference build-up index, NDBI). Besides, contribution intensity index was introduced to investigate the contribution effect of four ecological parameters on LST, and a new ecological index, integrated ecological index (IEI), was founded using the principal component analysis technique to integratedly represent its spatial and mathematical correlations with LST. Results indicate that four ecological parameters all possessed pronounced performance in impacting LST pattern in all dates: SAVI and NDMI were found to be correlated negatively with LST, whereas NDBI and NDSI correlated positively with LST. Additionally, SAVI had a profound impact on LST distribution compared with the other three parameters, and there was the biggest heating contribution in the lowest SAVI category. Further finding suggests that IEI as a new ecological index can be used to integratedly estimate the spatio-temporal change of LST, manifesting a negative correlation with LST. Our study thinks that the comprehensive characterization of surface ecological status is conducive to benefit us to better understand the spatio-temporal mechanism of thermal environment and ecosystem and to help urban decision-makers to execute effective conservation policies for the ecosystem. [ABSTRACT FROM AUTHOR]

Clear and green water bodies reflect more green light than red light, while brown water bodies reflect more red light than green light. It is thus believed that the normalized difference water indexes using the green band and infrared wavelengths (NDWIgreen) and the normalized difference water indexes using the red band and infrared wavelengths (NDWIred) would act differently in mapping inland water bodies with different colours. This study aims to evaluate the performance of NDWIgreenand NDWIredin mapping water bodies with different colours in the Yellow River Basin using the Landsat-8 Operational Land Imager (OLI) imagery. The results show that NDWIgreenand NDWIredachieve overall accuracy of 95.99–96.82% and 88.32–96.68% in clear water mapping, 95.58–96.35% and 93.50–94.60% in green water mapping, 88.12–92.63% and 90.08–93.10% in brown water mapping, respectively. It is shown that both NDWIgreenand NDWIredcan serve the purpose of inland water mapping. Moreover, the comparative analysis suggests that NDWIgreenis more suitable for clear and green water mapping, while NDWIredis more adequate for brown water mapping. [ABSTRACT FROM AUTHOR]

The vegetation and impervious surface area (ISA) are the most key indicators for the urban heat islands (UHI). This study used the normalized difference vegetation index (NDVI) as the indicator of vegetation abundance, the modified normalized difference impervious surface index (MNDISI) as the indicator of impervious surface fraction to estimate the land surface temperature (LST)–vegetation relationship and LST–ISA relationship. The land surface cover types were obtained by classification and regression tree (CART). Results demonstrate and verify that LST possessed strong negative correlations with NDVI and positive correlations with MNDISI at various spatial resolutions (30–960 m). Both correlation coefficients reached their strongest points at 30 m resolution, which is believed to be the operational scale of LST, NDVI and MNDISI. Further, information capacity (IC), as a spatial index, is used to characterize the spatial pattern of UHI. Results show that the IC of LST (LSTIC) possessed strong positive correlations with the IC of NDVI (NDVIIC) and the IC of MNDISI (MNDISIIC). It is suggested that the spatial pattern of UHI has a direct correspondence with the vegetation and ISA. [ABSTRACT FROM PUBLISHER]

Globalization is the major confronting challenge of higher education worldwide. And internationalization has become a response of higher education to meet the demands and challenges of globalization. In the recent decades, Chinese government has developed different policies to steer education reforms in order to achieve the aim of internationalization. The internationalizing process has produced contradictory changes in academic workplaces. This study explores how globalizing processes affect academic work and academics’ workplace learning in China. It reports on a series of policy changes, and the effects of these policies on the workplace learning of academics. The changing policies positively affect academics by bringing rich information and resources to their workplaces. But at the same time, academic work is becoming increasingly restrictive and controlled. The self-interests of the academics are reconstituted in terms of the interests of government and university, producing tension in academics’ workplaces. Moreover, the conflicts among different policies cause confusion. We argue that the changing policies in relation to the internationalization of higher education have affected academics in both positive and negative ways. Therefore, there is a call for policy-makers to adjust the existing policies in order to create a better policy environment for academics. [ABSTRACT FROM PUBLISHER]

This paper presents the common methods and corresponding drawbacks concerning nonlinear analysis of fluxgate excitation circuits and emphasizes the importance of nonlinear analysis for these circuits. With regard to the nonlinearity of the excitation circuit, this paper proposes the use of the core-measured hysteresis curve for mathematical analysis and the use of a nonlinear model that considers the coupling effect of the core and winding and influence of the historical magnetic field on the core for simulation analysis. The feasibility of mathematical calculations and simulation for the nonlinear study of fluxgate excitation circuit is verified via experiments. The results demonstrate that, in this regard, the simulation is four times better than a mathematical calculation. The simulation and experimental results of the excitation current and voltage waveforms under different excitation circuit parameters and structures are essentially consistent, with a difference in current of no more than 1 mA, thereby verifying the effectiveness of the nonlinear excitation analysis method. [ABSTRACT FROM AUTHOR]

Traditional controlled-source audio-frequency magnetotellurics (CSAMT) radiates symmetric beams using a grounded symmetric dipole (GSD). Only a tiny fraction of radiant energy is taken advantage of during the far-field (Ff) observation due to the low directivity of the GSD. In order to enhance the signal-to-noise ratio (SNR) during the Ff observation, it is necessary to reduce the transceiving distance (TD) or increase the transmitting power (TP), but both methods will cause many problems. Further, when using the tensor method for observation, GSDs in two vertical directions will be employed to radiate energy, and then a series of problems will occur such as an asymmetry of the SNR in two vertical directions if the geological conditions under the two GSDs vary widely. An arithmetic phase difference (APd) weighting asymmetric beamforming method (ABFM) in CSAMT is proposed in this paper, which uses a GSD array instead of a single GSD, and a signal with APd is transmitted to control the wavefront for beam steering. A significant enhancement (about 3 dB) of the SNR will occur by collecting the radiant energy in the region of concern (RoC) using ABFM. The analysis and simulation results demonstrate that under the premise of the same TD and TP, the ABFM has obvious advantages in improving energy utilization in CSAMT. In other words, the APd-weighted ABFM can deal with a complex noise environment in the field better than the traditional method. [ABSTRACT FROM AUTHOR]

Plasma Enhanced Chemical Vapor Deposition (PECVD) SiNx films deposited at the substrate temperatures from 20 to 180 °C and at the RF powers from 10 to 30 W were investigated. It is found that the films'' properties such as density, refractive index, composition and bonding configuration are varied with the substrate temperature and RF power. The moisture resistant ability of the deposited SiNx films was investigated by the water vapor permeation (WVP) measurement. Even at the low substrate temperature such as 50 °C, the moisture resistance of SiNx films keeps quite good. Our results can be applied in Organic Light Emitting Devices (OLED) packaging effectively. [Copyright &y& Elsevier]

• Nanocrystals were assembled in sodium alginate to prepare flexible sensors. • The emission and mechanical properties depended on the co-assembly ratio. • The assembled membrane emitted varied light under strain and humid stimuli. Uniaxially assembling cellulose nanocrystals (CNCs) can induce strong solid-state emission based on optical inelastic scattering, whereas the CNC assembly membranes are not flexible enough for further applications. Thus, we introduced CNC into flexible sodium alginate (SA) and further controlled the assembly structure of CNC to increase the membrane toughness and maintain the emission properties. The results indicated that the stretchability increased from 0.027 % to 37 % when 33–37% when 33 % SA was introduced. The assembly achirality was controlled by tuning CNC concentration in suspension, and the co-assembly could further control the wavelength of the assembly-induced emission from 420 nm to 440 nm. Furthermore, the improved stretchability made assembly membrane an optical sensor, whose excitation wavelength blue-shifted about 30 nm under a 30 % strain. The emission of the co-assembly membrane could also respond to humidity, and this cellulose-based material should have great potential in biosensor and wearable devices. [ABSTRACT FROM AUTHOR]

Purpose: Long intergenic non-coding RNA LINC01088 is a newly discovered long non-coding RNA (lncRNA). Its biological function in colorectal cancer (CRC) remains unknown. Methods: Here, 36 paired CRC and para-cancerous tissues were collected. In vitro, fluorescence in situ hybridization (FISH) assay, qPCR, western blotting analysis and cellular functional experiments, RNA immunoprecipitation (RIP) assay and dual-luciferase reporter system analysis were performed. In vivo, xenograft tumor mouse models were generated. Besides, patient-derived intestinal organoid (PDO) was generated ex vivo. Results: We found that LINC01088 was significantly upregulated in colorectal cancer tissues and CRC cell lines compared to adjacent normal tissues and colonic epithelial cells. High LINC01088 levels were correlated with adverse outcomes in patients with CRC. LINC01088 was mainly located in the cytoplasm. LINC01088 knockdown suppressed the proliferation, migration, invasion, and immune escape of colorectal cancer cells. Mechanistically, LINC01088 bound directly to miR-548b-5p and miR-548c-5p that were significantly upregulated Ras GTPase-activating protein-binding proteins 1 (G3BP1) and programmed death ligand 1 (PD-L1) expression, altering CRC cell phenotypes. In mouse xenograft models, LINC01088 knockdown restrained CRC tumor growth and lung metastasis. Furthermore, G3BP1 overexpression reversed LINC01088-knockdown-mediated inhibitory effects on tumor growth. Notably, LINC01088 knockdown downregulated PD-L1 expression, while G3BP1 overexpression restored PD-L1 expression in xenograft tumors. Besides, LINC01088 knockdown repressed CRC organoid growth ex vivo. Conclusion: Overall, these findings suggested that LINC01088 directly targeted miR-548b-5p and miR-548c-5p, promoting G3BP1 and PD-L1 expression, which facilitated colorectal cancer progression and immune escape. [ABSTRACT FROM AUTHOR]

Utilizing natural and renewable natural polysaccharides as substrates to fabricate films or spinning with high metal ion adsorption and retain their mechanical properties is essential but challenging for the treatment of polluted water systems. In this study, the adsorption film was prepared with excellent mechanical properties and adsorption properties by blending chitosan (CS), poly (vinyl pyrrolidone) (PVP), β-cyclodextrin (β-CD), and nanocellulose (NCC). Fourier transform infrared spectroscopy, X-ray diffraction analysis, and scanning electron microscopy were used to investigate the microstructure of the film. The effects of the NCC content, contact time, temperature, initial concentration, and pH on the adsorption of Cu(II) ion were investigated. X-ray photoelectron spectroscopy (XPS) was used to explore the adsorption mechanism. The results showed that a suitable content of NCC enhanced the tensile strength of the CS/PVP/β-CD/NCC composite film and improved its adsorption capacity under acidic conditions. The adsorption kinetics followed the pseudo-second-order kinetic model and the equilibrium data could be better described by the Langmuir isotherm. The thermodynamic parameters indicated that the adsorption of the Cu(II) ion onto the CS/PVP/β-CD/NCC film exhibited physical adsorption and spontaneous process. XPS analysis showed that the nitrogen-containing functional groups play an important role during the adsorption process. Therefore, applying this adsorbent to remove metal ions during wastewater treatment is promising. [ABSTRACT FROM AUTHOR]

This paper designs a three-axis closed-loop fluxgate system for geophysical prospecting, which contains excitation, induction, and feedback circuits. By analyzing and comparing the noise levels before and after the system operation, it is concluded that the main factor affecting the fluxgate performance is the excitation circuit noise. By analyzing the principle of fluxgate, the noise on the induction signal and feedback signal can reduce the accuracy of fluxgate and even lead to system instability in serious cases. In this paper, a passive filter circuit is designed to reduce the noise associated with the fundamental frequency from the source to ensure stable operation and improved performance of the system. Simulation and experimental data show that after using the filter circuit, the secondary frequency noise level of the induction signal and the feedback signal noise level are reduced by 10 times, and the trend capturing capability under external magnetic field is greatly improved. [ABSTRACT FROM AUTHOR]

Recently, deep generative models have become increasingly popular in unsupervised anomaly detection. However, deep generative models aim at recovering the data distribution rather than detecting anomalies. Moreover, deep generative models have the risk of overfitting training samples, which has disastrous effects on anomaly detection performance. To solve the above two problems, we propose a self-adversarial variational autoencoder (adVAE) with a Gaussian anomaly prior assumption. We assume that both the anomalous and the normal prior distribution are Gaussian and have overlaps in the latent space. Therefore, a Gaussian transformer net T is trained to synthesize anomalous but near-normal latent variables. Keeping the original training objective of a variational autoencoder, a generator G tries to distinguish between the normal latent variables encoded by E and the anomalous latent variables synthesized by T, and the encoder E is trained to discriminate whether the output of G is real. These new objectives we added not only give both G and E the ability to discriminate, but also become an additional regularization mechanism to prevent overfitting. Compared with other competitive methods, the proposed model achieves significant improvements in extensive experiments. The employed datasets and our model are available in a Github repository. [ABSTRACT FROM AUTHOR]

Plasmonic Au nanoparticle (NP)–decorated g-C3N4 nanosheets were synthesized by a direct in situ decomposition-thermal polymerization method with dicyandiamide and gold chloride trihydrate (HAuCl4·3H2O) as the precursors. Au NPs were closely anchored on the surface of g-C3N4 with high dispersion, and Au/g-C3N4 composites showed strong surface plasmon resonance in the visible light region. The photocurrent density of Au/g-C3N4 composite with 1 wt% Au (0.32 μA/cm2) was 6.3 times higher than that of pure g-C3N4 (0.05 μA/cm2) under simulated sunlight irradiation. The 1 wt% Au/g-C3N4 composite exhibited improved activity in the photodegradation of organic dyes under natural sunlight and enhanced photocatalytic water reduction performance under simulated sunlight illumination due to the uniform distribution of Au NPs and heterostructure at the interface of Au/g-C3N4. This work provided a new platform for the preparation of metal/g-C3N4 to replace traditional photoreduction or chemical reduction method. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) is defined as sudden ischemic death of myocardial tissue. Amphiregulin (Areg) regulates cell survival and is crucial for the healing of tissues after damage. However, the functions and mechanisms of Areg after MI remain unclear. Here, we aimed to investigate Areg's impact on myocardial remodeling. Mice model of MI was constructed and Areg−/− mice were used. Expression of Areg was analyzed using western blotting, RT–qPCR, flow cytometry, and immunofluorescence staining. Echocardiographic analysis, Masson's trichrome, and triphenyltetrazolium chloride staining were used to assess cardiac function and structure. RNA sequencing was used for unbiased analysis. Apoptosis and autophagy were determined by western blotting, TUNEL staining, electron microscopy, and mRFP‐GFP‐LC3 lentivirus. Lysosomal acidity was determined by Lysotracker staining. Areg was elevated in the infarct border zone after MI. It was mostly secreted by macrophages. Areg deficiency aggravated adverse ventricular remodeling, as reflected by worsening cardiac function, a lower survival rate, increased scar size, and interstitial fibrosis. RNA sequencing analyses showed that Areg related to the epidermal growth factor receptor (EGFR), phosphoinositide 3‐kinase/protein kinase B (PI3K‐Akt), mammalian target of rapamycin (mTOR) signaling pathways, V‐ATPase and lysosome pathways. Mechanistically, Areg exerts beneficial effects via increasing lysosomal acidity to promote autophagosome clearance, and activating the EGFR/PI3K/Akt/mTOR signaling pathway, subsequently inhibiting excessive autophagosome formation and apoptosis in cardiomyocytes. This study provides a novel evidence for the role of Areg in inhibiting ventricular remodeling after MI by regulating autophagy and apoptosis and identifies Areg as a potential therapeutic target in ventricular remodeling after MI. [ABSTRACT FROM AUTHOR]

Three types of digital predictive dead-beat current control algorithms (PDB-CCAs) for phase-shifted full-bridge DC–DC converters with peak current, valley current and average current are presented. The PDB-CCAs are derived directly from the switching characteristics and topological structures of the converters. The proposed algorithms can predict the inductor current in the next switching period by sampling the input voltage, output voltage and inductor current in the current switching period. To ensure the stability of the inductor current, the PDB-CCAs result in a greatly improved transient performance, since the inductor current tracks the reference in one switching period or less when a reference perturbation or current perturbation occurs. In addition, although the procedure for deriving the control algorithms is complex, they can be easily implemented by a digital controller after reasonable simplification. Finally, simulation and experimental results are obtained and they agree with the theoretical results, which demonstrate the validity of the proposed PDB-CCAs. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) data obtained by using an m-sequence source is typically segmented with an m-sequence cycle, and the random noise is suppressed by stacking the earth impulse responses recovered from each data segment. However, the stack cannot suppress the powerline noise, which is normally several orders of magnitude greater than the random noise. In this paper, the powerline noise reduction with different data lengths were compared by numerical simulation; the results show that there is always an optimal data length, not a single cycle but several cycles that can achieve maximum powerline noise suppression. The concept of an identification system was proposed and the identified earth impulse response is obtained by measuring the system output with the input of the voltage response. The optimal data length was summarized in two cases by analyzing the identification system with different data lengths. Coding frequency optimization was proposed to shorten the optimal data length to increase the stacking times. Finally, the validity of the theory described in this paper was verified by field data processing. Different from the traditional subtraction method and notch filter, the powerline suppression method presented here does not need a noise record or filter design; the powerline noise is suppressed accompanied by the identification processing without any additional workload; the simple and practical method provides a new insight into the powerline noise reduction. With this method, the utilization of field data is improved and the anti-noise performance of the m-sequence is also fully exploited. [ABSTRACT FROM AUTHOR]

As an effective active remote sensing technology for the exploration of shallow underground targets, ground-penetrating radar (GPR) is a detection method that can be used to obtain information about the characteristics of underground targets by transmitting an electromagnetic wave from an antenna and analyzing the propagation of the electromagnetic wave underground. Due to the frequency (1 MHz–3 GHz) of GPRs, the depth of geological exploration is shallow (0.1–30 m). In order to penetrate the deeper Earth, it is necessary to increase the size of the antenna in accordance with the wavelength ratio and, thus, reduce the radiation frequency. For most bi-static antenna GPRs, a dipole antenna is used as the transmitting antenna and another antenna device is used as a receiving antenna, with both being horizontally linearly polarized (LP) antennas. In some cases, such a design can cause problems, such as the multi-path effect and polarization mismatching. When a GPR is used for deep exploration, increased numbers of errors and greater signal attenuation during data reception and processing often occur. In contrast, at the radiation source, with the use of large-aperture multiple-dipole antennas and multi-channel sequential rotational excitation, the electromagnetic wave can radiate in the form of circular polarization at a low frequency. In the receiving antenna, the issues caused by the multi-path effect and polarization mismatching can be addressed, even if LP antennas are used. A novel sequential rotationally excited (SRE) circularly polarized (CP) multiple-dipole array for a bi-static antenna GPR for deep exploration is proposed in this paper. A large-aperture CP multiple-dipole array is used instead of a small-size LP dipole antenna. The analysis and simulation results demonstrated that, comparing circular polarization and linear polarization with the premise of the same transmitting power, the SRE CP multiple-dipole antenna array radiation source achieved a significant enhancement (about 7 dB) in the signal-to-noise ratio (SNR) as the radiant energy was collected at the receiving antenna. More importantly, by reducing the exploration frequency to 10 KHz, the exploration depth could also be greatly increased by about tenfold. [ABSTRACT FROM AUTHOR]

Harmonic noise represented by power-line noise is the main interference of Multi-transient electromagnetic (MTEM), and traditional filtering methods inevitably suffer from noise residue and waveform distortion. The key step in MTEM is the extraction of the earth impulse response, which is equivalent to filtering the voltage response signal using an identification system. This paper modulates the spectrum of the identification system by extending the source signal to increase the attenuation at these target frequencies in order to filter out harmonic noise when extracting the earth impulse response, which we named as Extended Spectrum Modulation Method (ESMM). This paper first deduces the mathematical relationship between data length and target frequency. The filtering of power-line harmonics by ESMM is then demonstrated and compared with a conventional notch filter. This paper also proposes a rapid deployment method for ESMM to improve data utilization. Since ESMM filters out noise while extracting the earth impulse response, there is no additional hardware cost or time overhead. Finally, a field experiment demonstrates the superior performance and ultimate convenience of ESMM. • The ESMM filters the periodic noise while extracting the earth impulse response. • The ESMM is achieved by modulating the spectrum of the identification system. • The target frequency can be flexibly adjusted with the extension times. • The ESMM is more practical, lower cost, and better performing than notch filters. [ABSTRACT FROM AUTHOR]

The preparation of linear polysilsesquioxanes having Si–OH side groups is not trivial, because direct condensation of multifunctional silanol derivatives would lead to branched or crosslinked polymers. We have successfully prepared an unsymmetrical double-decker silsesquioxane with a silyl hydride function at one end and two silanol groups at the other. Linear POSS polymers having Si–OH side groups are obtained selectively in good yields. The properties and potential applications are briefly presented. [ABSTRACT FROM AUTHOR]

TiO 2 nanorod spheres were synthesized in a highly acidic hydrothermal solution by using TiO 2 /SiO 2 spheres as template. Electron microscopy observation and X-ray diffraction analysis indicate that the dissolution of anatase TiO 2 in the template spheres leads to the growth of rutile TiO 2 nanorod on the surface of the template spheres in the initial stage of hydrothermal process and the deposition of anatase TiO 2 nanoparticles on the preformed nanorods in the later stage of hydrothermal process. Herein, SiO 2 in the template spheres assisted the loading of rutile TiO 2 nucleuses on the surface of template spheres through preventing the collapse of the template spheres in highly acidic hydrothermal solution. With the dissolution of anatase TiO 2 , the template spheres gradually transformed from solid to hollow. The nanorod hollow spheres prepared by a hydrothermal period of 24 h showed high stability of physical property, excellent cycle reproducibility of photocatalytic activity, and enhanced photocatalytic activity as compared with the template spheres. [ABSTRACT FROM AUTHOR]

Long-term low-dose ionizing radiation (LLIR) widely exists in human life and has been confirmed to have potential pathogenic effects on cancer and cardiovascular diseases. However, it is technically and ethically unfeasible to explore LLIR-induced phenotypic changes in the human cohort, leading to slow progress in revealing the pathogenesis of LLIR. In this work, we recruited 32 radiation workers and 18 healthy non-radiation workers from the same city with the same eating habits for radiation damage evaluation and metabolomics profiling. It was found that clear metabolic phenotypic differences existed between LLIR and non-LLIR exposed participants. Moreover, LLIR exposed workers can be further divided into two types of metabolic phenotypes, corresponding to high and low damage types respectively. 3-hydroxypropanoate and glycolaldehyde were identified as sensitive indicators to radiation damage, which specific response to the chromosomal aberration of workers and may be potential monitoring markers for LLIR protection. Taurine metabolism-related pathways were identified as the main differential metabolic pathway under LLIR inducing, which had been confirmed to have a response to acute or chronic radiation exposure. We expect our study can be helpful to LLIR damage monitoring and symptomatic intervention in the future. [Display omitted] • There are distinct metabolic phenotypic differences between radiation workers and health subjects. • Radiation workers with low or high radiation damage shown differential metabolic phenotype. • 3-Hydroxypropanoate and glycolaldehyde were identified with specific response to chromosomal aberration. • Taurine metabolism related pathways were the main differential metabolic pathway induced under LLIR exposure. [ABSTRACT FROM AUTHOR]

E Difference analysis of grain number in different panicle parts, the panicle is divided into 3 parts namely top (top, from 1-1 to 4-2 panicle positons), middle (mid, from 5-1 to 8-2 panicle positons) and bottom (bot, from 9-1 to 12-2 panicle positons) respectively. B Eating quality of different panicle locations under H treatment, the panicle is divided into 3 parts namely top (top, from 1-1 to 4-2 panicle positons), middle (mid, from 5-1 to 8-2 panicle positons) and bottom (bot, from 9-1 to 12-2 panicle positons) respectively. [Extracted from the article]

E Difference analysis of grain number in different panicle parts, the panicle is divided into 3 parts namely top (top, from 1-1 to 4-2 panicle positons), middle (mid, from 5-1 to 8-2 panicle positons) and bottom (bot, from 9-1 to 12-2 panicle positons) respectively. B Eating quality of different panicle locations under H treatment, the panicle is divided into 3 parts namely top (top, from 1-1 to 4-2 panicle positons), middle (mid, from 5-1 to 8-2 panicle positons) and bottom (bot, from 9-1 to 12-2 panicle positons) respectively. [Extracted from the article]

Ep type is an important morphological improvement (following dwarf breeding and ideal plant type) that has contributed to breeding super-high yielding, and shows a pleiotropic effect in increasing grain yield and also nitrogen-use efficiency (NUE) in rice. Nevertheless, it remains unclear whether Ep has adverse effects on eating quality and how it affects nitrogen uptake and assimilation. In this study, we developed a pair of near-isogenic lines (NILs) for panicle type (NIL-Ep, NIL-non Ep) in the Liaogeng 5 (LG5) and Akihikari (AKI) backgrounds. Rice plants of the NIL-Ep had higher grain numbers per panicle in the middle to bottom spike positions than plants of the NIL-non Ep. The increased grain number is not only is the key factor leading to increased yield but also is the reason for reduced the eating quality. The content of prolamin and glutelin was significantly higher in NIL-Ep, which resulted in higher hardness and worse viscosity of rice after cooking. In addition, the activity of several essential enzymes catalyzing nitrogen metabolism was higher in the NIL-Ep line grains than in the NIL-non Ep, especially from the mid to late grain filling stage. Based on these results, we conclude that Ep positively regulates grain protein accumulation, primarily through enhancing the activity of enzymes involved in nitrogen assimilation and redistribution during the mid to late grain-filling stage, resulting in excessive accumulation of grain protein and decreased eating quality. [ABSTRACT FROM AUTHOR]

Ep type is an important morphological improvement (following dwarf breeding and ideal plant type) that has contributed to breeding super-high yielding, and shows a pleiotropic effect in increasing grain yield and also nitrogen-use efficiency (NUE) in rice. Nevertheless, it remains unclear whether Ep has adverse effects on eating quality and how it affects nitrogen uptake and assimilation. In this study, we developed a pair of near-isogenic lines (NILs) for panicle type (NIL-Ep, NIL-non Ep) in the Liaogeng 5 (LG5) and Akihikari (AKI) backgrounds. Rice plants of the NIL-Ep had higher grain numbers per panicle in the middle to bottom spike positions than plants of the NIL-non Ep. The increased grain number is not only is the key factor leading to increased yield but also is the reason for reduced the eating quality. The content of prolamin and glutelin was significantly higher in NIL-Ep, which resulted in higher hardness and worse viscosity of rice after cooking. In addition, the activity of several essential enzymes catalyzing nitrogen metabolism was higher in the NIL-Ep line grains than in the NIL-non Ep, especially from the mid to late grain filling stage. Based on these results, we conclude that Ep positively regulates grain protein accumulation, primarily through enhancing the activity of enzymes involved in nitrogen assimilation and redistribution during the mid to late grain-filling stage, resulting in excessive accumulation of grain protein and decreased eating quality. [ABSTRACT FROM AUTHOR]

Background: Recaticimab (SHR-1209, a humanized monoclonal antibody against PCSK9) showed robust LDL-C reduction in healthy volunteers. This study aimed to further assess the efficacy and safety of recaticimab in patients with hypercholesterolemia.Methods: In this randomized, double-blind, placebo-controlled phase 1b/2 trial, patients receiving stable dose of atorvastatin with an LDL-C level of 2.6 mmol/L or higher were randomized in a ratio of 5:1 to subcutaneous injections of recaticimab or placebo at different doses and schedules. Patients were recruited in the order of 75 mg every 4 weeks (75Q4W), 150Q8W, 300Q12W, 150Q4W, 300Q8W, and 450Q12W. The primary endpoint was percentage change in LDL-C from the baseline to end of treatment (i.e., at week 16 for Q4W and Q8W schedule and at week 24 for Q12W schedule).Results: A total of 91 patients were enrolled and received recaticimab and 19 received placebo. The dose of background atorvastatin in all 110 patients was 10 or 20 mg/day. The main baseline LDL-C ranged from 3.360 to 3.759 mmol/L. The least-squares mean percentage reductions in LDL-C from baseline to end of treatment relative to placebo for recaticimab groups at different doses and schedules ranged from -48.37 to -59.51%. No serious treatment-emergent adverse events (TEAEs) occurred. The most common TEAEs included upper respiratory tract infection, increased alanine aminotransferase, increased blood glucose, and increased gamma-glutamyltransferase.Conclusion: Recaticimab as add-on to moderate-intensity statin therapy significantly and substantially reduced the LDL-C level with an infrequent administration schedule (even given once every 12 weeks), compared with placebo.Trial Registration: ClinicalTrials.gov , number NCT03944109. [ABSTRACT FROM AUTHOR]

To provide a basis for the high-temperature oxidation of ultra-high temperature ceramics (UHTCs), the oxidation behavior of Zr 3 [Al(Si)] 4 C 6 and a novel Zr 3 [Al(Si)] 4 C 6 -ZrB 2 -SiC composite at 1500 °C were investigated for the first time. From the calculation results, the oxidation kinetics of the two specimens follow the oxidation dynamic parabolic law. Zr 3 [Al(Si)] 4 C 6 exhibited a thinner oxide scale and lower oxidation rate than those of the composite under the same conditions. The oxide scale of Zr 3 [Al(Si)] 4 C 6 exhibited a two-layer structure, while that of the composite exhibited a three-layer structure. Owing to the volatilization of B 2 O 3 and the active oxidation of SiC, a porous oxide layer formed in the oxide scale of the composite, resulting in the degradation of its oxidation performance. Furthermore, the cracks and defects in the oxide scale of the composite indicate that the reliability of the oxide scale was poor. The results support the service temperature of the obtained ceramics. [ABSTRACT FROM AUTHOR]

A flat arid unmanned Gobi in northwest Gansu, China, has been recognized as a good location for a planned spent-fuel reprocessing plant site. To better assess its applicability and safety as a proposed site, it is important to understand the composition and characteristics of the local vadose zone. Laboratory tests were carried out to analyze the basic properties of the soil in the unsaturated layer, such as particle size, structure, chemical composition and mineralogical characteristics. The permeability coefficients at different depths were measured by three methods, including the single ring, double ring, and inverse auger methods. Four groups of probes were buried at depths of 0.2–4 m in the vadose zone to detect changes in matrix suction with water content in the dehydration state and to determine the field soil-water characteristics curve. Based on the measured hydrological and geological parameters, the migration of intermediate-level nuclides H-3, Co-60, and Cs-137 from the vadose zone into groundwater was simulated by HYDRUS-1D under different rainfall intensities. The simulation results showed that the vadose zone in the study area has a strong retention effect, in which the Co-60 and Cs-137 nuclides were retained in the vadose zone during the 1000-year simulation period. The radioactivity and distribution coefficients of the nuclides were the main factors affecting the time to reach the pollution standard at the groundwater level on a short time scale. Rainfall significantly increased nuclide migration speed on a large time scale. Finally, two engineering protection measures derived from weakening the driving force and increasing the migration path were proposed and were effective in a numerical simulation. • Vadose zone in a planned spent fuel reprocessing plant site was investigated. • Soil-water characteristic curve was fitted by field test and filter paper method. • Migration of H-3, Co-60, and Cs-137 in the vadose zone was simulated. [ABSTRACT FROM AUTHOR]

SiC MOSFETs have an excellent characteristic of high switching speed, which can improve the efficiency and power density of converters significantly. However, the fast switching processes of SiC MOSFETs cause serious crosstalk problems in bridge-arm configurations, which restricts the devices' performances. This paper presents a detailed and accurate improved crosstalk analytical model, which takes into account the nonlinear capacitances, the parasitic inductances, the reverse recovery characteristics of the anti-parallel diodes, and the nonlinear voltage switching and damping oscillation process. The novelty of the proposed model lies in the fact that under the condition of comprehensively considering all these non-ideal factors of the bridge-arm, the effects of multi-parasitic elements and multi-variables coupling to the crosstalk are hierarchically divided. The parasitic elements and their correlations are described in detail and the direct and indirect variables' impacts are clearly traced. Thus, according to the different variables switching stages, the influence processes of these parasitic elements and variables can be integrated and a complete equivalent analytical model of the crosstalk process can be derived. The simulation and experiment platforms are established and a series of experimental verifications and comparisons prove that the model can replicate experimental measurements of crosstalk with good accuracy and detail. [ABSTRACT FROM AUTHOR]

Rapid recombination of the photo-generated charge carriers leads to the poor photocatalytic nitrogen fixation property of pristine graphite-like carbon nitride (g-C 3 N 4). To enhance the photocatalytic performance of g-C 3 N 4 , nickel sulfide (NiS) nanoparticles were anchored onto the surface of g-C 3 N 4 by using the in-situ decomposition-thermal polymerization method in this work. The incorporation of NiS cocatalyst expanded the absorption range, enhanced the efficiency of separating photo-generated charge carriers, reduced the band gap from 2.78 eV to 2.47 eV, increased the specific surface area 7.1 m2·g−1 to 19.5 m2·g−1, and enlarged the photo-current density, which can inhibit the recombination of photo-generated charge carriers. Furthermore, the emergence of the nitrogen vacancy occurred during the in-situ synthetic process as a result of the thermal decomposition of thioacetamide hydrolysate, thereby leading to an enhancement in the photocatalytic nitrogen fixation efficiency. The results of the nitrogen fixation experiment demonstrated that 13 % NiS/g-C 3 N 4 exhibited the highest activity, with a photocatalytic nitrogen fixation rate of 8.15 mg/L. This rate is 7.6 times greater than that of pure g-C 3 N 4 , which can be attributed to several factors, including a higher separation rate of photogenerated electrons, a larger specific surface area, a wider range of responsiveness to visible light, and the presence of the nitrogen vacancy. [Display omitted] • NiS modified g-C 3 N 4 is prepared by an in-situ decomposition-thermal polymerization. • NiS/CN shows nitrogen vacancy, wide absorption range and efficient charge transfer. • NiS/CN exhibits enhanced photocatalytic nitrogen fixation performance. [ABSTRACT FROM AUTHOR]

Titanium carbide (TiC) fibers are attractive functional materials that find application in the areas of energy, environment, and biology. Herein, a simple precursor route is designed to prepare TiC fibers by means of electrospinning. The precursor is prepared by adding polyvinylpyrrolidone (PVP) to as-synthesized polytitanoxane (PTO), and the synthesis process, structure, and thermal behavior of the resulting TiC fibers are analyzed. Smooth and continuous precursor fibers with a uniform diameter of ~1.22 μm are obtained after the electrospinning of the precursor. With increase in the preparation temperature, the phase composition of the fibers evolves into TiC from TiC x O y via pyrolysis and carbothermal reduction. Chemical-state analysis results show that the surface of as-prepared TiC fibers exhibits very weak oxidation, thus leading to TiO 2 and TiC x O y formation. In addition, all the prepared fibers show uniform morphologies without adhesion. With the proposed approach, continuous TiC fibers with a diameter of ~0.55 μm can be obtained. [ABSTRACT FROM AUTHOR]

Biomimetic surfaces with the hierarchical structure consisting of multilayered pore microstructures and TiO 2 hollow nanostructures were fabricated by combining a modified breath figure method and a dip-coating technique. For creating the hierarchical structure, acetylacetone-chelated and non-chelated tetrabutyltitanates in the coating solution were used as the titanium sources to produce the titanium-based gel film and hollowly nanostructured TiO 2 , respectively. Meanwhile, the smaller and larger water droplets condensed in sequence during the breath figure process were used as the templates to generate the hollow structures and pore structures, respectively. The parameters of the hierarchical structures, including the pore diameter, pore density and the output of TiO 2 hollow nanostructures, were conveniently tailored by varying the volume ratio of tetrabutyltitanate to acetylacetone in the coating solution. The as-prepared titanium-based gel films on glass substrates can be transformed into the corresponding anatase TiO 2 films by a subsequent annealing process. The synthesized films were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction pattern, thermogravimetry and Fourier transform infrared spectroscopy. The designed hierarchical structure effectively endows the films with the rose-like superhydrophobic behavior, and the introduction of TiO 2 hollow nanostructures within multilayered pores plays an important role in the superhydrophobic property and the strong adhesion to a water droplet. • Introduction of chemical reaction in breath figure method. • Two-step condensation of water droplets. • Combination of pore microstructure and hollow nanostructure. • Tailorable parameters of the hierarchical structures. [ABSTRACT FROM AUTHOR]

A series of Dy3+ and Tm3+ co-doped Li 2 Gd 4 (WO 4) 7 (LGW) single-phase white phosphors were fast synthesized by microwave assisted solid-state reaction method. Single-ion doped LGW:Dy3+ and LGW:Tm3+ phosphors were synthesized to obtain quenching concentrations. The ideal white light (0.33, 0.33) locates on the straight line that connects the Commission Internationale de L'Eclairage (CIE) coordinates of LGW:Dy3+ and LGW:Tm3+. Therefore, Dy3+ and Tm3+ were selected to co-dope LGW to realize white light emission. By changing Dy3+ concentration, white light was obtained under the excitation wavelengths of 356 nm and 363 nm. Luminescence decay curves and the emission spectra of the co-doped phosphors were characterized to verify the existence of energy transfer between Tm3+ and Dy3+ in this single-phase phosphor. Energy transfer efficiency and energy transfer mechanism were investigated in detail. This fast synthesized single-phase white phosphor LGW:Dy3+, Tm3+ is a good candidate for the white light emitting diodes. [ABSTRACT FROM AUTHOR]

• Minimum Squared Error Method based on Modal Analysis for Source Location. • The microfiber coupler sensors are used to detect acoustic emission signals. • This method reduce the dependence of locating results on frequency selection. • This method automate the locating process of contour threshold modal analysis. • Both linear and planar location were performed on an aluminium thin plate. This study focuses on an improved modal analysis method to the source location using a microfiber coupler sensor (MFCS). This method uses the Minimum Squared Error(MSE) to reduce the dependence of locating results on frequency selection and automate the locating process of contour threshold modal analysis. First, the secondary enclosed package method of MFCS was studied to ensure that the signal detected by this sensor meets the requirements of the contour threshold modal analysis and can extend the MFCS working life as well. The MSE method was then presented detailed. Second, the directionality experiment of the MFCS was performed to determine the best layout method for sensors in planar localization. The planar source localization method with both two sensors and three sensors are then introduced. Last, both linear and planar location experiments were performed on an aluminium thin plate. The results indicate that the sensor packaged by cuboid glass tube is more suitable for practical ultrasonic testing; the location process is automated by valid contour extraction and initial frequency selection, and the linear error using this method is effectively reduced as well; the best arrangement of the sensor is to place the sensor at the corner of the planar, and the angle between the sensor and the horizontal line is 45°; compared with two sensors, the planar localization with three sensors provides a more accurate and high repeatability results. This study proved that the combination of the MFCS and the MSE method is quite feasible and can be applied to the planar localization in plate-like structures effectively. [ABSTRACT FROM AUTHOR]