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Actinidia arguta (A. arguta, kiwiberry) is a perennial deciduous vine with a strong overwintering ability. We hypothesized that trehalose metabolism, which plays a pivotal role in the stress tolerance of plants, may be involved in the cold acclimatization of A. arguta. Transcriptome analysis showed that the expression of AaTPPA, which encodes a trehalose-6-phosphate phosphatase (TPP), was upregulated in response to low temperatures. AaTPPA expression levels were much higher in lateral buds, roots, and stem cambia than in leaves in autumn. In AaTPPA-overexpressing (OE) Arabidopsis thaliana (A. thaliana), trehalose levels were 8–11 times higher than that of the wild type (WT) and showed different phenotypic characteristics from WT and OtsB (Escherichia coli TPP) overexpressing lines. AaTPPA-OE A. thaliana exhibited significantly higher freezing tolerance than WT and OtsB-OE lines. Transient overexpression of AaTPPA in A. arguta leaves increased the scavenging ability of reactive oxygen species (ROS) and the soluble sugar and proline contents. AaERF64, an ethylene-responsive transcription factor, was induced by ethylene treatment and bound to the GCC-box of the AaTPPA promoter to activate its expression. AaTPPA expression was also induced by abscisic acid. In summary, the temperature decrease in autumn is likely to induce AaERF64 expression through an ethylene-dependent pathway, which consequently upregulates AaTPPA expression, leading to the accumulation of osmotic protectants such as soluble sugars and proline in the overwintering tissues of A. arguta. [ABSTRACT FROM AUTHOR]

• A passive sampler was developed to measure inorganic and organic pollutants synchronously. • Vertical resolution of centimeters for pollutants could be obtained by the sampler. • The sediment role of source or sink for pollutant was identified by the passive sampler. In situ measurement of multiple pollutants coexisting in sediment porewater is an essential step in comprehensively assessing the bioavailability and risk of pollutants, but to date, this needs to be better developed. In this study, a passive sampler, consisting of an "I-shaped" supporting frame and inorganic/organic sampling units, incorporating equilibrium dialysis theory and kinetic/equilibrium sorption principle, was developed for the synchronous measurement of inorganic (e.g., phosphorus and metal(loid)s) and organic pollutants (e.g., parent and substituted PAHs). The equilibrium time and sampling rates were explored in laboratory tests to support in situ application. Profiles of pollutants in porewater within a vertical resolution of centimeters, i.e., 1 cm and 2 cm for inorganic and organic pollutants, respectively, were obtained by field deployment of the sampler for further estimation of diffusive fluxes across the sediment-water interface. The results suggested that the role of sediments for a specific pollutant may change (e.g., from "sink" to "source") during the sampling time. This study demonstrated the feasibility of synchronous measurement of inorganic and organic pollutants in sediment porewater by the passive sampler. In addition, it provided new insight for further investigation into the combined pollution effects of various pollutants in sediments. [Display omitted] [ABSTRACT FROM AUTHOR]

Bleeding is as particularly a serious phenomenon in Actinidia arguta and has important effects on this plant's growth and development. Here we used A. arguta to study the effects of bleeding on the growth and development of leaves and fruits after a bleeding episode. We detect and analyze physiological indices of leaves and fruit after bleeding. The result revealed that the relative electrical conductivity and malondialdehyde (MDA) of leaves increased in treatment. Nitro blue tetrazolium chloride (NBT) and 3,3-diaminobenzidine (DAB) staining revealed the accumulation of reactive oxygen species (ROS) in leaves after bleeding. The chlorophyll content and photosynthetic parameter of plants were also decreased. In fruits, pulp and seed water content decreased after the damage, as did fruit vitamin C (Vc), soluble sugar content, and soluble solids content (SSC); the titratable acid content did not change significantly. We therefore conclude that bleeding affects the physiological indices of A. arguta. Our study provides a theoretical basis for understanding the physiological changes of A. arguta after bleeding episodes and laying a timely foundation for advancing research on A. arguta bleeding and long-term field studies should be executed in order to gain insights into underlying mechanisms. [ABSTRACT FROM AUTHOR]

Distinguishing the respective contributions of various microbes to methylmercury (MeHg) production is critical for predicting MeHg bioaccumulation and exposure risk. Metabolic inhibitors have been commonly used to block the activity of specific microbial groups and identify primary Hg methylating microbes. By reviewing literatures and our empirical data, we demonstrate how multiple factors, including (1) the addition of inappropriate amounts of inhibitors, (2) a tendency to overlook microbial syntrophy, and (3) the absence of comprehensive proxy systems of Hg methylation, would impact result interpretation of this approach. We thus suggest that the design of inhibition assays should consider the environmental properties, e.g., background levels of electron acceptors, concentrations of metabolic substrates, and abundances of Hg methylating microbes. We also recommend that inhibitors should be added at multiple concentrations and that observed changes in Hg methylation should be assessed with comprehensive indicators. Revealing the key factors responsible for the improper usage of this method and inadequate interpretation of the results would help optimize inhibition assays for robust predictions of MeHg production in nature. [ABSTRACT FROM AUTHOR]

Senescence is the final stage of plant growth and development, and is a highly regulated process at the molecular, cellular, and organismal levels. When triggered by age, hormonal, or environmental cues, plants actively adjust their metabolism and gene expression to execute the progression of senescence. Regulation of senescence is vital for the reallocation of nutrients to sink organs, to ensure reproductive success and adaptations to stresses. Identification and characterization of hallmarks of leaf senescence are of great importance for understanding the molecular regulatory mechanisms of plant senescence, and breeding future crops with more desirable senescence traits. Tremendous progress has been made in elucidating the genetic network underpinning the metabolic and cellular changes in leaf senescence. In this review, we focus on three hallmarks of leaf senescence – chlorophyll and chloroplast degradation, loss of proteostasis, and activation of senescence-associated genes (SAG s), and discuss recent findings of the molecular players and the crosstalk of senescence pathways. [ABSTRACT FROM AUTHOR]

Mercury (Hg) could be microbially methylated to the bioaccumulative neurotoxin methylmercury (MeHg), raising health concerns. Understanding the methylation of various Hg species is thus critical in predicting the MeHg risk. Among the known Hg species, mercury sulfide (HgS) is the largest Hg reservoir in the lithosphere and has long been considered to be highly inert. However, with advances in the analytical methods of nanoparticles, HgS nanoparticles (HgS NPs) have recently been detected in various environmental matrices or organisms. Furthermore, pioneering laboratory studies have reported the high bioavailability of HgS NPs. The formation, presence, and transformation (e.g., methylation) of HgS NPs are intricately related to several environmental factors, especially dissolved organic matter (DOM). The complexity of the behavior of HgS NPs and the heterogeneity of DOM prevent us from comprehensively understanding and predicting the risk of HgS NPs. To reveal the role of HgS NPs in Hg biogeochemical cycling, research needs should focus on the following aspects: the formation pathways, the presence, and the environmental behaviors of HgS NPs impacted by the dominant influential factor of DOM. We thus summarized the latest progress in these aspects and proposed future research priorities, e.g., developing the detection techniques of HgS NPs and probing HgS NPs in various matrices, further exploring the interactions between DOM and HgS NPs. Besides, as most of the previous studies were conducted in laboratories, our current knowledge should be further refreshed through field observations, which would help to gain better insights into predicting the Hg risks in natural environment. [Display omitted] [ABSTRACT FROM AUTHOR]

The increase in atmospheric CO2 concentration is a significant factor in triggering global warming. CO2 is essential for plant photosynthesis, but excessive CO2 can negatively impact photosynthesis and its associated physiological and biochemical processes. The tetraploid Robinia pseudoacacia L., a superior and improved variety, exhibits high tolerance to abiotic stress. In this study, we investigated the physiological and proteomic response mechanisms of the tetraploid R. pseudoacacia under high CO2 treatment. The results of our physiological and biochemical analyses revealed that a 5% high concentration of CO2 hindered the growth and development of the tetraploid R. pseudoacacia and caused severe damage to the leaves. Additionally, it significantly reduced photosynthetic parameters such as Pn, Gs, Tr, and Ci, as well as respiration. The levels of chlorophyll (Chl a and b) and the fluorescent parameters of chlorophyll (Fm, Fv/Fm, qP, and ETR) also significantly decreased. Conversely, the levels of ROS (H2O2 and O2·−) were significantly increased, while the activities of antioxidant enzymes (SOD, CAT, GR, and APX) were significantly decreased. Furthermore, high CO2 induced stomatal closure by promoting the accumulation of ROS and NO in guard cells. Through a proteomic analysis, we identified a total of 1652 DAPs after high CO2 treatment. GO functional annotation revealed that these DAPs were mainly associated with redox activity, catalytic activity, and ion binding. KEGG analysis showed an enrichment of DAPs in metabolic pathways, secondary metabolite biosynthesis, amino acid biosynthesis, and photosynthetic pathways. Overall, our study provides valuable insights into the adaptation mechanisms of the tetraploid R. pseudoacacia to high CO2. [ABSTRACT FROM AUTHOR]

• The multiple phytohormones and TFs were identified and modulated with salt stresses. • Regarding common changes of phytohormones to both castor lines, PP2C homologs were all upregulated under salt stress. • The expression levels of ERF/AP2, WRKY and bHLH families as the predominant target participate in high salt stress response of castor. Soil salinity is one of the major environmental factors, influencing agricultural productivity of crops. As a non-edible and ideal oilseed crop, castor (Ricinus communis L.) has great industrial value in biofuel, but molecular mechanisms of salt stress regulation are still unknown. In this study, the differentially expressed genes (DEGs) for differential salt tolerance in two castor cultivar (wild castor : Y, cultivated castor 'Tongbi 5': Z) were identified. 12 libraries were sampled for Illumina high-throughput sequencing to consider 132,426 nonredundant unigenes and 31,221 gene loci. Multiple phytohormones and transcription factors (TFs) were correlated with salt-tolerance and differently enriched in these two genotypes. The type 2C protein phosphatases (PP2C) homologs were all upregulated under salt stress. Importantly, IAA (1), DELLA (1) and Jasmonate zim domain (JAZ) (1) were also identified and found to be differentially expressed. Based on the co-expressed module by regulatory networks and heatmap analysis, ERF/AP2, WRKY and bHLH families were prominently participate in high salt stress response of wild and cultivated castor. Finally, these results highlight that the hub DEGs and families were more accumulated in cultivated castor than those in wild castor, providing novel insights into the salinity adaptive mechanisms and genetic improvement in castor. [ABSTRACT FROM AUTHOR]

Yttrium oxide film is an important dielectric material, which has been widely used in the scientific and engineering fields. The microstructures of yttrium oxide films can be modified effectively by adjusting the substrate temperature and bias voltage, which also have effects on dielectric properties of yttrium oxide films. In this work, the dielectric properties of yttrium oxide films grown on Pt film, which exhibit the distinct microstructures with cubic-phase and monoclinic-phase domination manipulated by different substrate temperatures and bias voltages, have been investigated systematically. High substrate temperature as well as large bias voltage can decrease the loss tangent and enhance the dielectric constants up to 56 and 40, respectively. Furthermore, the driven force of temperature is more favorable than that of bias voltage for enhanced dielectric constant due to fewer defects. [ABSTRACT FROM AUTHOR]

Low-density polyethylene (LDPE) has been widely used as a sorbent for passive sampling of hydrophobic organic contaminants (HOCs) in aquatic environments. However, it has seen only limited application in passive sampling for measurement of freely dissolved concentrations of parent and substituted PAHs (SPAHs), which are known to be toxic, mutagenic and carcinogenic. Here, the 16 priority PAHs and some typical PAHs were selected as target compounds and were simultaneously determined by gas chromatography–mass spectrometer (GC–MS). Some batch experiments were conducted in the laboratory to explore the adsorption kinetics of the target compounds in LDPE membranes. The results showed that both PAHs and SPAHs could reach equilibrium status within 19–38 days in sorption kinetic experiments. The coefficients of partitioning between LDPE film (50 μm thickness) and water (K LDPE) for the 16 priority PAHs were in good agreement with previously reported values, and the values of K LDPE for the 9 SPAHs are reported in this study for the first time. Significant linear relationships were observed, i.e., log K LDPE = 0.705 × log K OW + 1.534 for PAHs (R 2 = 0.8361, p < 0.001) and log K LDPE = 0.458 × log K OW + 3.092 for SPAHs (R 2 = 0.5609, p = 0.0077). The selected LDPE film was also proven to meet the condition of "zero sink" for the selected target compounds. These results could provide basic support for the configuration and in situ application of passive samplers. Unlabelled Image [ABSTRACT FROM AUTHOR]

Herpetospermum caudigerum (Ser.) Baillis is an endangered species found in high altitude regions of Tibet in China. In this work, its genetic diversity and genetic structure were investigated based on nuclear and chloroplast DNA. A total of 426 fragments were scored using 10 amplified fragment length polymorphism (AFLP) primer combinations, and from these, 256 fragments (60.7%) were polymorphic and could differentiate these populations. The dendrogram revealed that populations from different altitude have rich genetic diversities (Ht = 0.156, Hs = 0.111, Gst = 0.287 and Nm = 1.618). The averages of the number of alleles (Na), effective number of alleles (Ne), Nei's genetic diversity (H) and Shannon's index (I) were 1.352, 1.188, 0.111 and 0.168, respectively. In addition, 5 P03-trnL-trnF-300 haplotypes and 3 P02-trnL-trnF-396 haplotypes were identified among the 4 populations, and 7 haplotypes were identified based on the combined fragments. The non-coding region P03-trnL-trnF-300 exhibited higher polymorphisms with the number of haplotypes, the abundant haplotype (gene) diversity and the nucleotide diversity. Tajima's test showed that all Tajima's D values were statistically significant at P < 0.05, indicating that natural selection has an effect on mutations in these fragments. Our results from H. caudigerum cpDNA indicated a high genetic diversity fixation index (Fst = 0.968) and showed greater genetic differentiation among populations (96.7%, P < 0.01) than analysis of nDNA (63.72%, P < 0.01). These results could lay the foundation for further understanding and conservation of H. caudigerum germplasm resources. [ABSTRACT FROM AUTHOR]

Wetlands are highly productive and biologically diverse environments that provide numerous ecosystem services, but can also be sources of methylmercury (MeHg) production and export. Mangrove wetlands contribute up to 15% of the coastal sediment carbon storage and ~10% of the particulate terrestrial carbon exported to the ocean. Thus, mercury (Hg) methylation in mangrove sediments and subsequent MeHg output to adjacent waters could have a great impact on global Hg cycling. In this review, we provide a comprehensive analysis of the literature on worldwide Hg concentrations in mangrove ecosystems, and the results reveal that a large range of total Hg (THg) and MeHg concentrations is detected in mangrove systems. Then, we discuss the potential roles of organic matter (OM) in controlling the Hg biogeochemistry in mangrove sediments. The intense OM decomposition by anoxic reduction (e.g., sulfate reduction) drastically affects sediment chemistries, such as redox potential, pH, and sulfur speciation, all of which may have a great impact on MeHg production. While the outwelling of carbon from mangroves has been extensively examined, little is known about their roles in exporting MeHg to adjacent waters. Our understanding of Hg biogeochemical processes in mangrove systems is constrained by the limited MeHg data and a lack of in-depth studies on the Hg methylation potential in this ecologically important environment. More efforts are needed to gain better insights into the contributions mangrove wetlands to the global Hg cycle. Unlabelled Image • A large range of mercury (Hg) concentrations is observed in mangrove systems. • Mangrove sediments exhibit several features that may favor MeHg production and accumulation. • Mangrove sediments may act as hotspots to export MeHg to adjacent coastal waters. [ABSTRACT FROM AUTHOR]

Abstract Eutrophication is a major environmental concern in lake systems, impacting the ecological risks of contaminants and drinking water safety. It has long been believed that eutrophication and thus algal blooms would reduce methylmercury (MeHg) levels in water, as well as MeHg bioaccumulation and trophic transfer (e.g., by growth dilution). In this study, however, we demonstrated that algae settlement and decomposition after algal blooms increased MeHg levels in sediments (54–514% higher), as evidenced by the results from sediments in 10 major lakes in China. These could in turn raise concerns about enhanced trophic transfer of MeHg and deterioration of water quality after algal blooms, especially considering that 9 out of the 10 examined lakes also serve as drinking water sources. The enhanced microbial MeHg production in sediments could be explained by the algal organic matter (AOM)-enhanced abundances of microbial methylators as well as the input of algae-inhabited microbes into sediments, but not Hg speciation in sediments: (1) Several AOM components (e.g., aromatic proteins and soluble microbial by product-like material with generally low molecular weights), rather than the bulk AOM, played key roles in enhancing the abundances of microbial methylators. The copies of Archaea- hgcA methylation genes were 51–397% higher in algae-added sediments; thus, MeHg production was also higher. (2) Input of algal biomass-inhabited microbial methylators contributed to 2–21% of total Archaea- hgcA in the 10 lake sediments with added algal biomass. (3) However, AOM-induced changes in Hg speciation, with implications on Hg availability to microbial methylators, played a minor role in enhancing microbial Hg methylation in sediments as seen in X-ray absorption near edge structure (XANES) data. Our results suggest the need to better understand the biogeochemistry and risks of contaminants in eutrophic lakes, especially during the period of algae settlement and decomposition following algal blooms. Graphical abstract Unlabelled Image Highlights • Algae settlement and decomposition enhanced net MeHg production in lake sediments. • Low molecular weight algal organic matter (AOM) increased the abundances of methylators. • Input of algae-inhabited microbes into sediments enhanced microbial MeHg production. • AOM-induced changes in Hg speciation played a minor role in Hg methylation. [ABSTRACT FROM AUTHOR]

Machining process is usually needed to fettle the assembly interfaces of large-scale component before the final assembly. There are several issues that make the process time and effort consuming, such as hard-to-machine material, difficulties in positioning and alignment, errors between as-built component, and as-designed model. Shop floor optimization is essential for machining this kind of large and complex workpiece but is limited by information loss from CAD/CAM to CNC (Computer Numerical Control) using traditional G&M codes. STEP-NC has been proven to perform excellently in data exchange between CAD/CAM and CNC but it does not support some special processes in machining the assembly interfaces. To solve these matters, this paper proposes a closed-loop machining system based on extended STEP-NC data models which cover aligning and laser tracker measuring process. The system consists of: (1) a STEP-NC compliant CAD/CAM system which exports STEP-NC programs, (2) a STEP-NC high-level process controller which translates STEP-NC programs and makes closed-loop optimization, and (3) CNCs and mechanical systems which perform machining and measuring tasks. In the end, a vertical tail of a large passenger plane is used as a study case to demonstrate the advantages of the proposed data models and systems. This paper contributes to machining the assembly interfaces of large-scale components, and the future development of STEP-NC in large-scale manufacturing. [ABSTRACT FROM AUTHOR]

Efficient oxygen utilization in the kidney may be supported by paracellular epithelial transport, a form of passive diffusion that is driven by preexisting transepithelial electrochemical gradients. Claudins are tight-junction transmembrane proteins that act as paracellular ion channels in epithelial cells. In the proximal tubule (PT) of the kidney, claudin-2 mediates paracellular sodium reabsorption. Here, we used murine models to investigate the role of claudin-2 in maintaining energy efficiency in the kidney. We found that claudin-2-null mice conserve sodium to the same extent as WT mice, even during profound dietary sodium depletion, as a result of the upregulation of transcellular Na-K-2Cl transport activity in the thick ascending limb of Henle. We hypothesized that shifting sodium transport to transcellular pathways would lead to increased whole-kidney oxygen consumption. Indeed, compared with control animals, oxygen consumption in the kidneys of claudin-2-null mice was markedly increased, resulting in medullary hypoxia. Furthermore, tubular injury in kidneys subjected to bilateral renal ischemia-reperfusion injury was more severe in the absence of claudin-2. Our results indicate that paracellular transport in the PT is required for efficient utilization of oxygen in the service of sodium transport. We speculate that paracellular permeability may have evolved as a general strategy in epithelial tissues to maximize energy efficiency. [ABSTRACT FROM AUTHOR]

Interface engineering has emerged as a fertile and efficacious approach to turn functional properties in the field of film systems. In this work, the interfacial properties of sputtered yttrium oxide films on zinc sulfide substrate (Y 2 O 3 /ZnS) were analyzed by transmission electron microscopy (TEM), X-ray photoelectron spectrum (XPS) depth profile and nano-scratch measurement. An interface layer with the depth of 20 nm between Y 2 O 3 film and ZnS substrate was directly observed by TEM. Under different film growth conditions, although the interfacial features including interfacial width and composition distribution exhibit similar behavior, it is found that higher cohesive strength is obtained under a special substrate bias voltage of −160 V at low substrate temperature. Such an enhanced mechanical property can be understood by the role of physisorbed oxygen in the interfacial region, in which less physisorbed oxygen with van der Waals bonds leads to a strong adhesion. Our results provide a favorable strategy to achieve strong adhesion between oxide and sulfide at low temperature, which are urgent in future micro-electric applications. [ABSTRACT FROM AUTHOR]

Videos have diverse content that can assist students in learning. However, because videos are linear media, video users may take a longer time than readers of text to evaluate the context. Therefore, the process of video search may vary from one user to another depending on the users' individual characteristics, and the effectiveness of video learning may also vary across individuals. This study evaluated 100 Taiwanese fifth graders searching for videos related to “understanding animals” on YouTube and examined the effects of the students' metacognitive strategies (planning, monitoring, and evaluating) and verbal-imagery cognitive style on their video searches. The observable indicators were quantitative (search behaviors, search performance, and learning performance) and qualitative (search process observations and interviews). The study concludes that metacognitive strategy is the primary influencer of video search. Students with better metacognitive skills used fewer keywords, browsed fewer videos, and spent less time evaluating videos, but they achieved higher learning performance. They reviewed the video metadata information on the user interface and did not attempt to watch videos on the video recommendation lists, particularly videos that were irrelevant to the task requirements. During the course of the searches, keyword usage had a significant influence on the students' search performance and learning performance. The fewer keywords the students used, the better search and learning performance they were able to achieve. Our results are different from those of previous studies on text, image, and map searches. Accordingly, users must adopt different search strategies when using various types of search engines. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of deposition conditions on the properties of yttrium oxide thin films. The paper focuses on the texture, optical and mechanical properties. With this objective, a series of yttrium oxide thin films with different thicknesses were deposited by direct current (DC) unbalanced reactive magnetron sputtering at high and low pumping speed. By changing the oxygen flow, depositions were performed in the three characteristic deposition modes for reactive magnetron sputtering, i.e., metallic, transition and poisoned mode. By using an oxygen flow directed to the substrate, full oxidation of the samples, as shown by X-ray photoelectron spectroscopy (XPS), in the three modes is obtained. Crystallographic characterization by X-ray diffraction (XRD) shows that films crystallize in the cubic phase with a strong (222) out-of-plane orientation at low oxygen flow. As the oxygen flow increases a mixture of cubic and monoclinic phase is obtained. In poisoned mode, the films consist of the cubic phase with preferred (420) orientation. Scanning electron microscopy (SEM) cross sections show, with increasing oxygen flow, a loss of the columnar structure. As the oxygen flow rates increase through the metallic, transition, and the poisoned mode, the grain size becomes gradually smaller. An overview diagram of all experimental results uncovers that the textural changes are closely linked to the oxygen partial pressure rather than the oxygen flow. The optical properties of films were investigated by spectroscopic ellipsometry (SE). The films with a columnar structure demonstrate superior hardness and modulus as well as the high plasticity. [ABSTRACT FROM AUTHOR]

A state-of-health (SOH) estimation method for electric vehicles (EVs) is presented with three main advantages: (1) it provides joint estimation of cell's aging states in terms of power and energy (i.e., SOHP and SOHE)-because the determination of SOHP and SOHE can be reduced to the estimation of the ohmic resistance increase and capacity loss, respectively, the ohmic resistance at nominal temperature will be taken as a health indicator, and the capacity loss is estimated based on a mechanistic model that is developed to describe the correlation between resistance increase and capacity loss; (2) it has wide applicability to various ambient temperatures-to eliminate the effects of temperature on the resistance, another mechanistic model about the resistance against temperature is presented, which can normalize the resistance at various temperatures to its standard value at the nominal temperature; and (3) it needs low computational efforts for on-board application-based on a linear equation of cell's dynamic behaviors, the recursive least-squares (RLS) algorithm is used for the resistance estimation. Based on the designed performance and validation experiments, respectively, the coefficients of the models are determined and the accuracy of the proposed method is verified. The results at different aging states and temperatures show good accuracy and reliability. [ABSTRACT FROM AUTHOR]

In order to understand the growth behavior of yttrium oxide films driven by thermodynamics and kinetics, two fundamental growth parameters, substrate heating and biasing, were investigated to control film structure and properties comprehensively. We observed two distinct areas, normal deposition area (area 1) and abnormal deposition area (etching area, area 2) at different substrate bias voltages regardless of the substrate temperature. X-ray diffraction (XRD) results show that heating promotes cubic phase formation, whereas ion bombardment induces monoclinic phase growth. Atomic force microscopy (AFM) measurements exhibit that the ions slightly enlarge the surface islands in area 1, whereas they flatten and smoothen the surface in area 2. X-ray photoelectron spectroscopy (XPS) results demonstrate that high temperature suppresses the physisorbed oxygen, and the ion bombardment favorably selects oxygen etching in area 1, causing excess oxygen vacancies. This selectivity almost disappears in area 2. Furthermore, the refractive index and band gap can be enhanced by both substrate temperature and bias voltage. The surface wettability of films can be modulated by the surface chemical composition. [ABSTRACT FROM AUTHOR]

Necrosis and apoptosis are two distinct types of mechanisms that mediate ischemic injury. But a signaling point of convergence between them has yet to be identified. Here, we show that activated death-associated protein kinase 1 (DAPK1), phosphorylates p53 at serine-23 (pS23) via a direct binding of DAPK1 death domain (DAPK1DD) to the DNA binding motif of p53 (p53DM). We uncover that the pS23 acts as a functional version of p53 and mediates necrotic and apoptotic neuronal death; in the nucleus, pS23 induces the expression of proapoptotic genes, such as Bax, whereas in the mitochondrial matrix, pS23 triggers necrosis via interaction with cyclophilin D (CypD) in cultured cortical neurons from mice. Deletion of DAPK1DD (DAPK1DDΔ) or application of Tat-p53DM that interrupts DAPK1-p53 interaction blocks these dual pathways of pS23 actions in mouse cortical neurons. Thus, the DAPK1-p53 interaction is a signaling point of convergence of necrotic and apoptotic pathways and is a desirable target for the treatment of ischemic insults. [ABSTRACT FROM AUTHOR]

Histone H2B monoubiquitination (H2Bub) is being recognized as a regulatory mechanism that controls a range of cellular processes in plants, but the molecular mechanisms of H2Bub that are involved in responses to biotic stress are largely unknown. In this study, we used wild-type and H2Bub loss-of-function mutations of Arabidopsis (Arabidopsis thalinna) to elucidate which of its mechanisms are involved in the regulation of the plant's defense response to Verticillium dahliae (Vd) toxins. We demonstrate that the depolymerization of the cortical microtubules (MTs) was different in the wild type and the mutants in the response to Vd toxins. The loss-of-function alleles of HISTONE MONOUBIQUITINATION1 and HISTONE MONOUBIQUITINATION2 mutations present a weaker depolymerrzation of the MTs, and protein tyrosine phosphorylation plays a critical role in the regulation of the dynamics of MTs. Moreover, H2Bub is a positive regulator of the gene expression of protein tyrosine phosphatases. These findings provide direct evidence for H2Bub as an important modification with regulatory roles in the defense against Vd toxins and demonstrate that H2Bub is involved in modulating the dynamics of MTs, likely through the protein tyrosine phosphatase-mediated signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: A series of yttrium oxide films has been fabricated on Si (100) wafers by different substrate temperatures based on reactive magnetron sputtering technology. And the evolution of composition, microstructure and optical properties of Y2O3 films has been investigated by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and spectroscopic ellipsometry (SE). It is shown that stoichiometric Y2O3 with much strong Y O bond and cubic nanophase with larger size notably enhance the optical properties, especially refractive index. At low substrate temperature, the composition of Y2O3 films has nonstoichiometry feature accompanying with much physisorbed oxygen (Oδ) compared with these at high temperature. Increasing substrate temperature promotes the formation of Y O bonds, approaching the stoichiometry with lower Oδ content. The film commences crystallizing at room temperature, and transformation of crystalline phase from monoclinic to cubic occurs, along with preferred (111) orientation and large grain as temperature increases. The results facilitate clear relationship between the characterizations of Y2O3 film and growth parameters, also, it can be realized that adjustment of optical constants of Y2O3 films in a large range having the aid of substrate temperature to obtain desirable composition and structure for optical applications. [Copyright &y& Elsevier]

Zinc-doped indium oxide (IZO) film, as an important transparent conductive oxide, has attracted increasing attention in various scientific and engineering areas. In the present work, discharge-voltage and reactive-oxygen controlled IZO films were grown by magnetron sputtering and studied systematically. The microstructure, element distribution and chemical bonding of IZO films were investigated by X-Ray diffraction (XRD), transmission electron microscope (TEM), Energy Dispersive X-Ray Spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The optical and electrical properties of IZO films were studied by controlled oxygen and discharge voltage. The typical microstructure of IZO films with optimal optical and electric properties has been characterized. High discharge voltage and matched oxygen vacancies could promote the low resistivity of IZO films, which could be determined by the electronic concentration and mobility. • IZO films were grown at room temperature by two strategies of oxygen and discharge voltage. •Oxygen supply promotes the decreases of oxygen vacancies and Zn content. •More oxygen promotes IZO film with higher transparency and larger bandgap. •Both high discharge voltage and matched oxygen content bring IZO film the superior carrier concentration and mobility. [ABSTRACT FROM AUTHOR]

Yttrium oxide films were prepared on silicon wafers by reactive magnetron sputtering at different oxygen flow rates to investigate the microstructure and optical properties for desirable planar optical waveguiding applications. Under the different conditions of target surface, the deposition rate, structure, and optical properties have great changes. The deposition rate increases to the maximum, and then monotonically decreases. Oxygen content in films increases and the composition of films transforms from stoichiometry to an oxygen-rich state. YO films grow with the (222) preferred growth orientation at low oxygen flow rate, and then turn into the (622) orientation; the microstructure evolves from crystal structure to amorphous state as oxygen flow rate increases from 2 to 12 sccm. Sufficient oxygen makes films low-order structure and oxygen-rich films have poor crystallinity. Very smooth film has been obtained at oxygen flow rate of 12 sccm. The refractive index can be greatly modulated by the oxygen-content factor. It is convincing that the controllable structure and optical properties of YO films can be achieved by adjustment the oxygen flow rate for desired optical design and applications. [ABSTRACT FROM AUTHOR]

Excessive secretion of triglyceride-rich very low-density lipoproteins (VLDL-TG) contributes to diabetic dyslipidemia. Earlier studies have indicated a possible role for the hypothalamus and autonomic nervous system in the regulation of VLDL-TG. In the current study, we investigated whether the autonomic nervous system and hypothalamic neuropeptide Y (NPY) release during fasting regulates hepatic VLDL-TG secretion. We report that, in fasted rats, an intact hypothalamic arcuate nucleus and hepatic sympathetic innervation are necessary to maintain VLDL-TG secretion. Furthermore, the hepatic sympathetic innervation is necessary to mediate the stimulatory effect of intracerebroventricular administration of NPY on VLDL-TG secretion. Since the intracerebroventricular administration of NPY increases VLDL-TG secretion by the liver without affecting lipolysis, its effect on lipid metabolism appears to be selective to the liver. Together, our findings indicate that the increased release of NPY during fasting stimulates the sympathetic nervous system to maintain VLDL-TG secretion at a postprandial level. [ABSTRACT FROM AUTHOR]

Abstract: Google Earth search function was used to study the impacts of small-scale spatial ability, large-scale environmental cognition, and geographical knowledge on new technology usage. The participants were 153 junior high students from central Taiwan. Geography grades served as indicators of prior knowledge, mental rotation and abstract reasoning skills as indicators of spatial ability, and sketch maps of school neighborhoods as indicators of environmental cognition (including landmark representation, intersection representation, and frame of reference). Lastly, the authors announced the landmarks searching worksheet and asked the participants to accomplish 16 familiar and unfamiliar landmark searching tasks using Google Earth with keyword search function disabled. The result showed the strongest predictor of landmark searching performance is ‘frame of reference’ in environmental cognition, followed by ‘mental rotation’ of spatial ability, ‘landmark representation’ of environmental cognition, and geographical knowledge. Google Earth landmark searches require complex cognitive processing; therefore, our conclusion is that GIS-supported image search activities give students good practice of active knowledge construction. [Copyright &y& Elsevier]

Abstract: Web searches entail complex cognitive processes influenced by individual differences, and users with similar cognitive or skill factors tend to develop multiple search strategies. The authors analyze such strategies in terms of level of thinking style (global versus local), search targets, and six search behavior indicators and report (a) a significant relationship between different thinking style levels and individual search target types and (b) that different thinking style level conditions can cause significant differences in search behavior performance regarding maximum depth of exploration, revisited pages, and Web pages visited for refining answers. The findings suggest that high global style users tend to disperse their targets to comprehend the search task while high local style users elaborate on a few specific topics. Furthermore, high global style users skim more, require less explicit answers, and are less likely to explore an issue in depth compared to high local style or bi-high style individuals. The results confirm that thinking style level is an important factor affecting search intention. To improve search experiences, search engine designers should incorporate human factors into their products so as to take advantage of personal learning approaches. [Copyright &y& Elsevier]

We study the solvability of the Cauchy problem (1.1)–(1.2) for the largest possible class of initial values, for which (1.1)–(1.2) has a local solution. Moreover, we also study the critical case related to the initial value u[sub 0] , for 1 < p < ∞. [ABSTRACT FROM AUTHOR]

One of the hallmarks of plant senescence is the global transcriptional reprogramming coordinated by a plethora of transcription factors (TFs). However, mechanisms underlying the interactions between different TFs in modulating senescence remain obscure. Previously, we discovered that plant ABS3 subfamily MATE transporter genes regulate senescence and senescence‐associated transcriptional changes. In a genetic screen for mutants suppressing the accelerated senescence phenotype of the gain‐of‐function mutant abs3‐1D, AUXIN RESPONSE FACTOR 2 (ARF2) and PHYTOCHROME‐INTERACTING FACTOR 5 (PIF5) were identified as key TFs responsible for transcriptional regulation in the ABS3‐mediated senescence pathway. ARF2 and PIF5 (as well as PIF4) interact directly and function interdependently to promote senescence, and they share common target genes such as key senescence promoting genes ORESARA 1 (ORE1) and STAY‐GREEN 1 (SGR1) in the ABS3‐mediated senescence pathway. In addition, we discovered reciprocal regulation between ABS3‐subfamily MATEs and the ARF2 and PIF5/4 TFs. Taken together, our findings reveal a regulatory paradigm in which the ARF2‐PIF5/4 functional module facilitates the transcriptional reprogramming in the ABS3‐mediated senescence pathway. Synopsis: The late endosome‐localized ABS3 subfamily of MATE transporters regulates senescence and senescence‐associated gene expression through mechanisms which are not well understood. Here, developmental transcription factors ARF2 and PIF5/4 are found to interact to control transcriptional regulation in the ABS3‐mediated senescence pathway.Mutations in ARF2 and PIF5 suppress precocious senescence caused by abs3‐1D, a gain‐of‐function mutant allele of ABS3.ARF2 and PIF5/4 can regulate senescence both together and independently.ARF2 and PIF5 physically interact and share common target genes, such as the key senescence‐promoting genes ORE1 and SGR1.ABS3‐subfamily MATEs and the ARF2‐PIF5/4 functional module regulate each other's activity to fine‐tune senescence. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg) production in paddy soils and its accumulation in rice raise global concerns since rice consumption has been identified as an important pathway of human exposure to MeHg. Sulfur (S) amendment via fertilization has been reported to facilitate Hg methylation in paddy soils under anaerobic conditions, while the dynamic of S-amendment induced MeHg production in soils with increasing redox potential remains unclear. This critical gap hinders a comprehensive understanding of Hg biogeochemistry in rice paddy system which is characterized by the fluctuation of redox potential. Here, we conducted soil incubation experiments to explore MeHg production in slow-oxidizing paddy soils amended with different species of S and doses of sulfate. Results show that the elevated redox potential (1) increased MeHg concentrations by 10.9%−35.2%, which were mainly attributed to the re-oxidation of other S species to sulfate and thus the elevated abundance of sulfate-reducing bacteria, and (2) increased MeHg phytoavailability by up to 75% due to the reductions in acid volatile sulfide (AVS) that strongly binds MeHg in soils. Results obtained from this study call for attention to the increased MeHg production and phytoavailability in paddy soils under elevated redox potentials due to water management, which might aggravate the MeHg production induced by S fertilization and thus enhance MeHg accumulation in rice. [ABSTRACT FROM AUTHOR]

Cupressus gigantea W. C. Cheng & L. K. Fu is an endemic conifer tree species that is distributed widely along the northern portion of the deep gorge of the Yarlung Tsangbo River on the Tibetan Plateau. However, as a key plant species growing on the Tibetan plateau, C. gigantea has since become an endangered species due to habitat loss and degradation, overexploitation, and other factors. It has been listed as a first-grade national protected wild plant species in China. Accordingly, to conserve this plant species, we should obtain more information on its genetic structure. In this study, the genetic diversity and structure among 67 samples were evaluated by the inter-simple sequence repeat (ISSR) technique. Overall, 78 bands were produced with a molecular length of 200 bp to 3100 bp using 10 ISSR primers. The mean values for the average number of alleles (Na), effective number of alleles (Ne), Nei's gene diversity (H), and Shannon's information index (I) were 1.529, 1.348, 0.199, and 0.293, respectively. Additionally, the number of polymorphic loci (NPLs) and percentage of polymorphic loci (PPLs) averaged 41.25 and 52.90, respectively. Further, total variation among populations was 14.2%, while that within populations was 85.8%; accordingly, the within-population genetic differentiation was found to be significant (p < 0.001). These results demonstrated that a genetic structure model with K = 3 fitted the data best, which agreed with the unweighted pair group method with arithmetic average (UPGMA) cluster and the principal coordinate analysis (PCoA). These findings are beneficial for ensuring the development and genetic protection of C. gigantea populations in the future. [ABSTRACT FROM AUTHOR]

Mercury (Hg) contamination in mangrove ecosystems has received increasing attention in recent years. Although many studies have investigated methylmercury (MeHg) contamination and its relationship to a number of environmental factors in mangrove sediments, the production of MeHg in this carbon-rich ecosystem has not been fully evaluated. In this study, we measured the total mercury (THg) and MeHg concentrations in the sediments collected from seven mangrove forests in China. In addition, we examined the origin and quality of sedimentary organic matter (OM), trying to evaluate their influence on the MeHg accumulation in mangrove sediments. We found that litterfall played an important role in regulating THg and MeHg contents in mangrove sediments. THg and MeHg concentrations in the mangrove sediments were positively correlated to OM content and the labile fraction of the OM. Multiple evidence (stable carbon isotopes, monosaccharide compositions, and biogenic silica) suggested that OM in mangrove sediments was dominated by input from litterfall. THg and MeHg concentrations were elevated at the sediments with higher input of mangrove OM. We observed that addition of mangrove litter stimulated the production of MeHg under anaerobic conditions. Overall, our results suggested that litterfall acted as a source of inorganic Hg, labile carbon, and low-molecular-weight OM which greatly favor the Hg methylation. Our study provides new insights into the MeHg production in mangrove sediments. Unlabelled Image • Litterfall played an important role in regulating sedimentary THg and MeHg. • THg and MeHg contents were positively correlated to the labile fraction of OM. • THg and MeHg contents were elevated at the sediments with higher input of mangrove OM. • Mangrove litter stimulated MeHg production in sediments under anaerobic conditions. [ABSTRACT FROM AUTHOR]

Castor (Ricinus communis L.), known as castor oil plant or castor bean, is a non-edible oilseed crop. In the present study, the genetic diversity among 54 samples (3 wild and 51 cultivated) collected worldwide was evaluated using inter-simple sequence repeats (ISSRs) and random amplified polymorphic DNA (RAPD) markers. A total of 9 ISSR primers produced 83 high-resolution bands with 61 (74.53%) as polymorphic. The percentage of polymorphic bands per primer and the genetic similarity coefficient ranged from 54.55% (UBC-836) to 100% (UBC-808) and from 0.74 to 0.96, respectively. A total of 11 out of 20 RAPD primers amplified unique polymorphic products with an average percentage of polymorphic bands of 60.98% (56 polymorphic bands out of a total of 90 bands obtained). The percentage of polymorphic bands per primer ranged from 25% (OPA-02 and B7) to 90.91% (B21) with the genetic similarity coefficient ranging from 0.73 to 0.98. The unweighted pair group method with arithmetic averages (UPGMA) dendrogram using two molecular markers divided 54 castor genotypes into three groups. Furthermore, based on morphological data, all 54 castor varieties were grouped into three main clusters. The genetic diversity analysis based on two molecular makers showed that most varieties from China were closely related to each other with three varieties (GUANGDONGwild, ZHEJIANGWild, and HANNANWild) belonging to a wild group separated from most of the cultivated castor samples from China, India, France, and Jordan. These results suggested that the cultivated castor contains a narrow genetic base. Accordingly, we recommend that wild castor genetic resources be introduced for breeding novel castor varieties. Furthermore, the Vietnam, Malaysia, Indonesia, and Nigeria accessions were clustered into the same group. The results of principal coordinate analysis (PCoA) and UPGMA cluster analysis were consistent with each other. The findings of this study are important for future breeding studies of castor. [ABSTRACT FROM AUTHOR]

As the biggest inter-basin water transfer scheme in the world, the South-to-North Water Diversion Project (SNWD) was designed to alleviate the water crisis in North China. The main channel of the middle route of the SNWD is of great concern in terms of the drinking water quality. In this study, we tested the hypothesis that the dissolved organic matter (DOM) derived from the planktonic algae causes the rising levels of COD Mn along the middle route by monitoring data on water quality (2015-2019, monthly resolution). The results showed that algal density in the main channel increased along the channel and was significantly correlated with COD Mn (p < 0.01). Five fluorescent components of DOM, including tyrosine-like (14.85%), tryptophan-like (22.48%), microbial byproduct-like (26.34%), fulvic acid-like (11.41%), and humic acid-like (24.92%) components, were detected. The level of tyrosine-like components increased along the channel and was significantly correlated with algal density (p <0.01), indicating that algae significantly changed the level of DOM in the channel. Algal decomposition and metabolism were found to be the main mechanisms that drive the changes in COD Mn. Therefore, controlling algal density would be an important measure to prevent further increase in COD Mn and for the guarantee of excellent water quality. [Display omitted] [ABSTRACT FROM AUTHOR]

To understand the influence of salt content in soil on the photosynthetic physiological indexes of spring wheat with trickle irrigation, the changes of the photosynthetic physiological indexes of spring wheat and the stomatal limitation and non-stomatal limitation features of photosynthesis were analyzed so as to provide theoretical basis and technical support for spring wheat cultivation in salinealkali soils with trickle irrigation. Pot experiment was conducted to investigate changes of the photosynthetic characteristics of spring wheat under different salt contents in soil (0.15% (CK), 0.80%, 1.70%, and 2.60%). The results showed that under different conditions of salt content, the daily variations of photosynthetic physiological indexes were similar, and the "noon nap" phenomenon during photosynthesis was obvious. Leaf stomatal conductance of spring wheat was suppressed by the salts in soil, resulting in the decreases of net photosynthetic rate, water utilization efficiency and solar energy utilization efficiency; leaf photosynthesis of spring wheat was restrained by the simultaneous existing of stomatal and nonstomatal factors; decrease of the net photosynthetic rate was mainly caused by stomatal factors under low salt content conditions and by non-stomatal factors under high salt content conditions. The spring wheat leaves had relatively high net photosynthetic rates in soils with initial salt contents of 0.15% and 0.80%. According to the results from this study, it is preliminarily concluded that spring wheat with trickle irrigation can be planted in saline-alkali soils with salt content lower than mild salinization soil. [ABSTRACT FROM AUTHOR]

There is growing evidence that incorporating crop straw into soils, which is being widely encouraged in many parts of the world, could increase net methylmercury (MeHg) production in soils and MeHg accumulation in crops. We explored the possibility of mitigating the risk of increased MeHg levels under straw amendment by transforming straw into biochar (BC). Greenhouse and batch experiments were conducted, in which soil MeHg concentrations, MeHg phytoavailability and accumulation in rice, dynamics of sulfate, nitrate and abundances of sulfate reducing bacteria (SRB) were compared in ‘Control’ (Hg contaminated soil), ‘Straw’ (soil with 1% rice straw), ‘Straw + BC’ (soil with 1% straw and 1% biochar), and ‘Straw + BC + N’ (soil with 1% straw, 1% biochar and 0.12% nitrate). Our results indicate that straw amendment increased MeHg concentrations in soils (28–136% higher) and rice plants (26% higher in grains, ‘Straw’ versus ‘Control’), while co-application of biochar with straw reduced grain MeHg levels (60% lower, ‘Straw + BC’ versus ‘Straw’). This could be mainly attributed to the reduced MeHg availability to rice plants (phytoavailability, extraction rates of MeHg by ammonium thiosulfate) under biochar amendment (64–99% lower, ‘Straw + BC’ versus ‘Straw’). However, biochar amendment enhanced soil MeHg levels (5–75% higher, ‘Straw + BC’ versus ‘Control’). Interestingly, nitrate addition helped reduce soil MeHg concentrations (11–41% lower, ‘Straw + BC + N’ versus ‘Straw + BC’) by facilitating nitrate reduction while inhibiting SRB activities. Subsequently, addition of nitrate with biochar, compared with biochar alone, further reduced grain MeHg levels by 34%. Therefore, straw biochar together with nitrate could possibly be effective in mitigating the risk of MeHg under straw amendment. Furthermore, the results evidence the impacts of straw management on the risk posed by MeHg in soils and emphasize the necessity to carefully consider the straw management policy in Hg-contaminated areas. [ABSTRACT FROM AUTHOR]

Xinjiang Region of China is one of the most typical and representative arid areas worldwide, along with severe soil salinization issue. Planting spring wheat and sequential cropping silage corn in Northern Xinjiang using drip irrigation has become an effective way to relieve soil salinity stress, which improves the simple agricultural structure in the past and ensures food security in this area. However, neither the effects of different soil salinities on the growth and yield of spring wheat and silage corn, nor their desalination effect correspondingly was clear until now. Therefore, a pot experiment was conducted at Shihezi, Xinjiang from March to June 2015. The study aimed to establish the quantitative correlations between the parameters mentioned above and came up with the appropriate soil salinity threshold in Northern Xinjiang area. The results confirmed that the soils in all treatments were desalinated after the whole growth period, and the decreasing rates varied within 18.89%-44.08% and 11.06%-30.83% for two plants, which showed linear and quadratic correlations with initial soil salinity, respectively (R2>0.92**, p<0.05). Meanwhile, higher soil salinity would inhibit crop growth and yield, and the initial soil salinity also represented the negative quadratic correlations with growth parameters (R2>0.92**, p<0.01). The inhibition effect was enhanced with larger initial soil salinity. After the comprehensive consideration of soil salinity variation, crop growth and yield, the initial soil salinity was recommended under 8.91 g/kg and 5.54 g/kg to plant spring wheat and sequential cropping silage corn in Northern Xinjiang using drip irrigation. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC), as a typical representative of the third-generation semiconductor material, has performance advantages in wide band gap, high thermal conductivity, high breakdown electric field and large electron drift velocity, etc., and is considered to be one of the ideal materials for high temperature, high frequency, high power and high voltage devices. SiC can effectively break through the physical limits of traditional Si-based power semiconductor devices, known as a green energy device that drives the "new energy revolution". As the core material for the manufacture of power devices, the growth of SiC single crystal substrate is very important, especially the preparation of single 4H-SiC polytype. Due to the better crystallographic compatibility and similar formation free energy among different polytypes, the grown SiC bulk crystals are prone to produce polytype inclusions and then seriously affect the device performance. Therefore, in this paper, the basic principle, growth process and existing problems of SiC crystal prepared by physical vapor transport (PVT) method are summarized firstly. Then the possible inducing factors for the formation of polytype inclusions were given and the relevant mechanisms are also discussed. In addition, the common identification methods of SiC polytype structures are further introduced. Finally, a prospect for the research of SiC single crystal are made. [ABSTRACT FROM AUTHOR]

• • The large-sized 4H-SiC single crystals were grown via sublimation technique. • • Impact of crucible structure on growth behavior was systematically investigated. • • SiC crystal grown in specific crucible exhibits superior characteristics. Silicon carbide (SiC), as the wide bandgap semiconductor, has gradually attracted attention from investigators due to the excellent integrated performance, widely recognized as a revolution in the electronic devices. For these applications, it is crucial to prepare the high-quality SiC crystal ingot by optimizing growth parameters and crucible structures. In this study, the effect of TaC coating and graphite paper on the growth process of SiC ingot were investigated compared to the growth in conventional graphite crucible through modeling and experiment. We demonstrated that the grown crystal using TaC-coated graphite relay ring and graphite paper surrounded the inner wall of powder container shows the superior characteristics in terms of the crystalline perfection and interface shape. In addition, the new crucible structure can provide a low-cost solution to prepare SiC crystal ingot using PVT method. [ABSTRACT FROM AUTHOR]

Narrow space characteristic is a common structural feature of aircraft assembly, which puts forward higher requirements for the end-effector of a robot drilling system. This paper proposed a new robotic simple and fast drilling system for aircraft automatic assembly. The robot drilling system and control scheme are designed. The end-effector is designed and calculated theoretically. The workflow of the whole system is designed and analyzed. Besides, a new calibration method is proposed for the system calibration includes the calibration of the robot end-effector and the calibration of the robot system relative to the machined parts. Finally, some drilling experiments are designed to verify the effectiveness of the proposed system. The results show that the newly designed robotic drilling system can meet the requirements of aircraft part drilling, such as the drilling accuracy is better than 0.5 mm, the drilling process is more stable, and the rigidity of the system is better. The drilling error of the hole diameter of this system can be controlled below 0.1 mm. The relative distances between holes in the X and Y direction and the hole edge distance meet the technical requirements, and all errors can be controlled to less than 0.5 mm, respectively. [ABSTRACT FROM AUTHOR]

The launch of state certification for community health workers (CHWs) in Massachusetts in 2018 aimed to promote and champion this critical workforce. However, concerns exist about unintentional adverse effects of certification. Given this, we conducted 2 cross-sectional surveys to evaluate this certification policy.We conducted surveys of CHW employers and CHWs in 3 sample frames: community health centers and federally qualified health centers, acute-care hospitals, and community-based organizations. We administered the surveys in 2016 (before certification launch) and 2021 (after certification launch) to answer the following questions: Was certification associated with positive outcomes among CHWs after its launch? Did harmful shifts occur among the CHW workforce and employers after certification launch? Was certification associated with disparities among CHWs after its launch?Certification was associated with higher pay among certified (vs noncertified) CHWs, better perceptions of CHWs among certified (vs noncertified) CHWs, and better integration of certified (vs noncertified) CHWs into care teams. We found no adverse shifts in CHW workforce by sociodemographic variables or in CHW employer characteristics (most notably CHW employer hiring requirements) after certification launch. After certification launch, certified and uncertified CHWs had similar demographic and educational characteristics. However, certified CHWs more often worked in large, clinical organizations while uncertified CHWs most often worked in medium-sized community-based organizations.Our evaluation of Massachusetts CHW certification suggests that CHW certification was not associated with workforce disparities and was associated with positive outcomes. Our study fills a notable gap in the research literature and can guide CHW research agendas, certification efforts in Massachusetts and other states, and program efforts to champion this critical, grassroots workforce. [ABSTRACT FROM AUTHOR]

The present study aimed to explore the importance of P53 and Cox-2 protein expression in esophageal cancer and assess their influence on prognosis. The expression of P53 and Cox-2 was assessed in esophageal cancer samples from 195 patients subjected to radical surgery at Changzhou First People's Hospital (Changzhou, China) between May 2010 and December 2011. Expression of P53 and Cox-2 proteins were detected in 60.5% (118/195) and 69.7% (136/195) of the samples, respectively, and were co-expressed in 43.1% (84/195) of the samples. A correlation was identified between P53 expression and overall survival (OS) (P=0.0351) as well as disease-free survival (DFS) (P=0.0307). In addition, the co-expression of P53 and Cox-2 also correlated with OS (P=0.0040) and DFS (P=0.0042). P53 expression (P=0.023), TNM staging (P<0.001) and P53/Cox-2 co-expression (P=0.009) were identified as independent factors affecting OS in patients with esophageal cancer via a Cox multivariate regression model analysis. A similar analysis also identified P53 expression (P=0.020), TNM staging (P<0.001) and P53/Cox-2 co-expression (P=0.008) as independent prognostic factors influencing DFS in these patients. Binary logistic regression analysis demonstrated a correlation between P53 expression (P=0.012), TNM staging (P<0.001), tumor differentiation level (P=0.023) and P53/Cox-2 co-expression (P=0.021), and local recurrence or distant esophageal cancer metastasis. The results of the present study indicate that P53 and Cox-2 proteins may act synergistically in the development of esophageal cancer, and the assessment of P53/Cox-2 co-expression status in esophageal cancer biopsies may become an important diagnostic criterion to evaluate the prognosis of patients with esophageal cancer. [ABSTRACT FROM AUTHOR]

The battery internal temperature estimation is important for the thermal safety in applications, because the internal temperature is hard to measure directly. In this work, an online internal temperature estimation method based on a simplified thermal model using a Kalman filter is proposed. As an improvement, the influences of entropy change and overpotential on heat generation are analyzed quantitatively. The model parameters are identified through a current pulse test. The charge/discharge experiments under different current rates are carried out on the same battery to verify the estimation results. The internal and surface temperatures are measured with thermocouples for result validation and model construction. The accuracy of the estimated result is validated with a maximum estimation error of around 1 K. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have been considered to be potent biomarkers for early disease diagnosis and for cancer therapy. The rapid and selective detection of miRNAs without reverse transcription and labelling is highly desired. Herein, we report a simple and label-free miRNA detection method that is based on the Duplex-Specific Nuclease (DSN)-Assisted simple target miRNA recycling procedure. The interaction of the G-quadruplex DNA structure with N-methyl mesoporphyrin IX (NMM) led to a label-free signal output. Under the optimised conditions, this method allowed for simple, rapid, and sequence-specific detection of miR-141 over a dynamic range from 1 fM to 100 nM with a linear range from 1 pM to 100 nM. Moreover, our method offered an excellent capacity to discriminate between miRNA family members with just one mismatched nucleotide. This simple and label-free strategy holds great potential in applications in biomedical research and in early clinical diagnostics. [ABSTRACT FROM AUTHOR]

Background: The composition of the claudin paracellular pore region is incompletely known. Results: Cysteine-scanning mutagenesis of the first extracellular domain of claudin-2 was used to identify all pore-lining residues and their intrapore locations. Conclusion: This study maps out the claudin-2 pore region. Significance: This advances understanding of the structure-function relationship of claudin pores. [ABSTRACT FROM AUTHOR]