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The temperature of industrial gas containing harmful H2S can reach hundreds of degrees. However, few processes can be used directly for H2S removal from industrial high-temperature gas. In this work, three polyoxometalates with different central atoms ((n-Bu4N)3VMo12O40, (n-Bu4N)3PMo12O40, and (n-Bu4N)4[α-SiMo12O40]) were synthesized and dissolved in four ionic liquids (Bmim]Cl, [Bmim]HCO3, [Bmim]Mes, or [Bmim]OAc) for H2S removal from high-temperature (90–180 °C) gases. The result showed that (n-Bu4N)3VMo12O40/[Bmim]OAc exhibited the optimal desulfurization performance, maintaining more than 98.6% desulfurization efficiency within 10 h. The reacted desulfurization solution can be regenerated by blowing air. FT-IR and XPS results show that both the central atom V and the coordination atom Mo of the polyoxometalate are involved in the oxidation of H2S; after the regeneration by introducing air, V(+IV) and Mo(+IV) recovered to V(+V) and Mo(+VI), respectively. Our research shows that (n-Bu4N)3VMo12O40/[Bmim]OAc is an efficient, easy-to-regenerate, and suitable high-temperature gas desulfurization solution. [ABSTRACT FROM AUTHOR]

This paper is concerned with the parameter estimation of non-linear discrete-time systems from noisy state measurements in the state-space form. A novel sparse Bayesian convex optimisation algorithm is proposed for the parameter estimation and prediction. The method fully considers the approximation method, parameter prior and posterior, and adds Bayesian sparse learning and optimization for explicit modeling. Different from the previous identification methods, the main identification challenge resides in two aspects: first, a new objective function is obtained by our improved Stein approximation method in the convex optimization problem, so as to capture more information of particle approximation and convergence; second, another objective function is developed with L 1 -regularization, which is sparse method based on recursive least squares estimation. Compared with the previous study, the new objective function contains more information and can easily mine more important information from the raw data. Three simulation examples are given to demonstrate the proposed algorithm's effectiveness. Furthermore, the performances of these approaches are analyzed, including parameter estimation of root mean squared error (RMSE), parameter sparsity and prediction of state and output result. [ABSTRACT FROM AUTHOR]

For the symmetrical mixture model and mixture test area, the lattice point set is used to partition, and then the corresponding test statistics can be constructed. In this paper, we first propose the partition methods under the lattice point sets and obtain several sub-simplexes without common interior points. Furthermore, we present a method for constructing a uniform design on the simplex using the center points of these sub-simplexes. The designs satisfy the uniformity of maximum distance deviation and provide good results for the mean square error deviation. Finally, the uniformity test on the mixture region is considered and illustrated by examples. [ABSTRACT FROM AUTHOR]

Verticillium dahliae is a soil-borne hemibiotrophic fungus that can lead to plant vascular disease and significant economic loss worldwide. Its hosts include over 400 dicotyledon plant species, such as annual herbs, perennials, and woody plants. The average yield loss of cotton crop caused by Verticillium wilt is approximately 10–35%. As the control of this disease is an urgent task for many countries, further understanding of the interaction between plants and V. dahliae is essential. Fungi can promote or inhibit plant growth, which is important; however, the most important relationship between plants and fungi is the host–pathogen relationship. Plants can become resistant to V. dahliae through diverse mechanisms such as cell wall modifications, extracellular enzymes, pattern recognition receptors, transcription factors, and salicylic acid (SA)/jasmonic acid (JA)/ethylene (ET)-related signal transduction pathways. Over the last decade, several studies on the physiological and molecular mechanisms of plant resistance to V. dahliae have been undertaken. In this review, many resistance-related genes are summarised to provide a theoretical basis for better understanding of the molecular genetic mechanisms of plant resistance to V. dahliae. Moreover, it is intended to serve as a resource for research focused on the development of genetic resistance mechanisms to combat Verticillium wilt. [ABSTRACT FROM AUTHOR]

A bifunctional electrocatalyst with high efficiency and low costs for overall water splitting is critical to achieving a green hydrogen economy and coping with the energy crisis. However, developing robust electrocatalysts still faces huge challenges, owing to unsatisfactory electron transfer and inherent activity. Herein, NiFe LDH/NiS2/VS2 heterojunctions have been designed as freestanding bifunctional electrocatalysts to split water, exhibiting enhanced electron transfer and abundant catalytic sites. The optimum NiFe LDH/NiS2/VS2 electrocatalyst exhibits a small overpotential of 380 mV at 10 mA cm−2 for overall water splitting and superior electrocatalytic performance in both hydrogen and oxygen evolution reactions (HER/OER). Specifically, the electrocatalyst requires overpotentials of 76 and 286 mV at 10 mA cm−2 for HER and OER, respectively, in alkaline electrolytes, which originate from the synergistic interaction among the facilitated electron transfer and increasingly exposed active sites due to the modulation of interfaces and construction of heterojunctions. [ABSTRACT FROM AUTHOR]

MiR399 plays an important role in plant growth and development. The objective of the present study was to elucidate the evolutionary characteristics of the MIR399 gene family in grapevine and investigate its role in stress response. To comprehensively investigate the functions of miR399 in grapevine, nine members of the Vvi-MIR399 family were identified based on the genome, using a miRBase database search, located on four chromosomes (Chr 2, Chr 10, Chr 15, and Chr 16). The lengths of the Vvi-miR399 precursor sequences ranged from 82 to 122 nt and they formed stable stem–loop structures, indicating that they could produce microRNAs (miRNAs). Furthermore, our results suggested that the 2 to 20 nt region of miR399 mature sequences were relatively conserved among family members. Phylogenetic analysis revealed that the Vvi-MIR399 members of dicots (Arabidopsis, tomato, and sweet orange) and monocots (rice and grapevine) could be divided into three clades, and most of the Vvi-MIR399s were closely related to sweet orange in dicots. Promoter analysis of Vvi-MIR399s showed that the majority of the predicted cis-elements were related to stress response. A total of 66.7% (6/9) of the Vvi-MIR399 promoters harbored drought, GA, and SA response elements, and 44.4% (4/9) of the Vvi-MIRR399 promoters also presented elements involved in ABA and MeJA response. The expression trend of Vvi-MIR399s was consistent in different tissues, with the lowest expression level in mature and young fruits and the highest expression level in stems and young leaves. However, nine Vvi-MIR399s and four target genes showed different expression patterns when exposed to low light, high light, heat, cold, drought, and salt stress. Interestingly, a putative target of Vvi-MIR399 targeted multiple genes; for example, seven Vvi-MIR399s simultaneously targeted VIT_213s0067g03280.1. Furthermore, overexpression of Vvi_MIR399e and Vvi_MIR399f in Arabidopsis enhanced tolerance to drought compared with wild-type (WT). In contrast, the survival rate of Vvi_MIR399d-overexpressed plants were zero after drought stress. In conclusion, Vvi-MIR399e and Vvi-MIR399f, which are related to drought tolerance in grapevine, provide candidate genes for future drought resistance breeding. [ABSTRACT FROM AUTHOR]

Melatonin, an indoleamine widely found in animals and plants, is considered as a candidate phytohormone that affects responses to a variety of biotic and abiotic stresses. In plants, melatonin has a similar action to that of the auxin indole-3-acetic acid (IAA), and IAA and melatonin have the same biosynthetic precursor, tryptophan. Salt stress results in the rapid accumulation of melatonin in plants. Melatonin enhances plant resistance to salt stress in two ways: one is via direct pathways, such as the direct clearance of reactive oxygen species; the other is via an indirect pathway by enhancing antioxidant enzyme activity, photosynthetic efficiency, and metabolite content, and by regulating transcription factors associated with stress. In addition, melatonin can affect the performance of plants by affecting the expression of genes. Interestingly, other precursors and metabolite molecules associated with melatonin can also increase the tolerance of plants to salt stress. This paper explores the mechanisms by which melatonin alleviates salt stress by its actions on antioxidants, photosynthesis, ion regulation, and stress signaling. [ABSTRACT FROM AUTHOR]

Silver powder, as the primary component of solar silver paste, significantly influences various aspects of the paste's performance, including printing, sintering, and conductivity. This study reveals that, beyond the shape and size of the silver powders, their microstructure is a critical factor influencing the performance of both silver powders and silver pastes in solar cell applications. The growth process leads to the formation of either polycrystalline aggregated silver powder or crystal growth silver powder. Analyzing the performance characteristics of these different microstructures provides guidance for selecting silver powders for silver pastes at different sintering temperatures. Polycrystalline aggregated silver powder exhibits higher sintering activity, with a sintering initiation temperature around 450 °C. The resulting silver paste, sintered at 750 °C, demonstrates a low sheet resistance of 2.92 mΩ/sq and high adhesion of 2.13 N. This silver powder is suitable for formulating silver pastes with lower sintering temperatures. The solar cell electrode grid lines have a high aspect ratio of 0.37, showing poor uniformity. However, due to the high sintering activity of the silver powder, the glass layer dissolves and deposits more silver, resulting in excellent conductivity, a low contact resistance of the silver electrode, a low series resistance of the solar cell of 1.23 mΩ, and a high photoelectric conversion efficiency of 23.16%. Crystal growth silver powder exhibits the highest tap density of 5.52 g/cm3. The corresponding silver paste shows improved densification upon sintering, especially at 840 °C, yielding a sheet resistance of 2.56 mΩ/sq and adhesion of 3.05 N. This silver powder is suitable for formulating silver pastes with higher sintering temperatures. The solar cell electrode grid lines are uniform with the highest aspect ratio of 0.40, resulting in a smaller shading area, a high fill factor of 81.59%, and a slightly higher photoelectric conversion efficiency of 23.17% compared to the polycrystalline aggregated silver powder. [ABSTRACT FROM AUTHOR]

Among the critical global crises curbing world development and sustainability, air quality degradation has been a long-lasting and increasingly urgent one and it has been sufficiently proven to pose severe threats to human health and social welfare. A higher level of model prediction accuracy can play a fundamental role in air quality assessment and enhancing human well-being. In this paper, four types of machine learning models—random forest model, ridge regression model, support vector machine model, extremely randomized trees model—were adopted to predict PM2.5 concentration in ten cities in the Jing-Jin-Ji region of north China based on multi-sources spatiotemporal data including air quality and meteorological data in time series. Data were fed into the model by using the rolling prediction method which is proven to improve prediction accuracy in our experiments. Lastly, the comparative experiments show that at the city level, RF and ExtraTrees models have better predictive results with lower mean absolute error (MAE), root mean square error (RMSE), and higher index of agreement (IA) compared to other selected models. For seasonality, level four models all have the best prediction performances in winter time and the worst in summer time, and RF models have the best prediction performance with the IA ranging from 0.93 to 0.98 with an MAE of 5.91 to 11.68 μg/m3. Consequently, the demonstration of how each model performs differently in each city and each season is expected to shed light on environmental policy implications. [ABSTRACT FROM AUTHOR]

Cervical spondylotic myelopathy (CSM) is a chronic disorder of the spinal cord. ROI-based features on diffusion tensor imaging (DTI) provide additional information about spinal cord status, which would benefit the diagnosis and prognosis of CSM. However, the manual extraction of the DTI-related features on multiple ROIs is time-consuming and laborious. In total, 1159 slices at cervical levels from 89 CSM patients were analyzed, and corresponding fractional anisotropy (FA) maps were calculated. Eight ROIs were drawn, covering both sides of lateral, dorsal, ventral, and gray matter. The UNet model was trained with the proposed heatmap distance loss for auto-segmentation. Mean Dice coefficients on the test dataset for dorsal, lateral, and ventral column and gray matter were 0.69, 0.67, 0.57, 0.54 on the left side and 0.68, 0.67, 0.59, 0.55 on the right side. The ROI-based mean FA value based on segmentation model strongly correlated with the value based on manual drawing. The percentages of the mean absolute error between the two values of multiple ROIs were 0.07, 0.07, 0.11, and 0.08 on the left side and 0.07, 0.1, 0.1, 0.11, and 0.07 on the right side. The proposed segmentation model has the potential to offer a more detailed spinal cord segmentation and would be beneficial for quantifying a more detailed status of the cervical spinal cord. [ABSTRACT FROM AUTHOR]

A series of carbon-coated LiMn1−xFexPO4 (x = 0, 0.1, 0.2, 0.3, 0.4) materials are successfully constructed using glucose as carbon sources via sol-gel processes. The morphology of the synthesized material particles are more regular and particle sizes are more homogeneous. The carbon-coated LiMn0.8Fe0.2PO4 material obtains the discharge specific capacity of 152.5 mAh·g−1 at 0.1 C rate and its discharge specific capacity reaches 95.7 mAh·g−1 at 5 C rate. Iron doping offers a viable way to improve the electronic conductivity and lattice defects of materials, as well as improving transmission kinetics, thereby improving the rate performance and cycle performance of materials, which is an effective method to promote the electrical properties. [ABSTRACT FROM AUTHOR]