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Based on macroscopic qualitative observation, microscopic quantitative analysis, low-temperature adsorption, high-pressure mercury intrusion and three-dimensional CT scanning, the spatial structure and heterogeneity of the #5 coal from the eastern Ordos Basin, Shanxi Formation, are quantitatively characterized. The following observation were studied: 1) The main body of the #5 coal was intact structural coal seam, with the density of cleats gradually increasing from north to south. 2) The microscopic composition of the #5 coal is dominated by desmocollinite, which contains small amounts of inertinite and inorganic minerals, with the inorganic component mainly composed of carbonate rocks and a small amount of clay. The carbon content and the content of its inorganic minerals in the #5 coal gradually decrease toward the inner basin, caused by transport distance and depositional environment. 3) At the micrometer scale, no significant pores were observed, and the #5 coal bed is primarily composed of micro-mesopores smaller than 40 nm, with a small number of 50∼100 nm macropores. Simultaneously, micro-fractures in the coal bed were well developed; by using mercury intrusion data of the bimodal feature of the pore throat, indicates the coexistence of micrometer-scale micro-fractures and nanometer-scale mesopores within the coal, with pronounced differences and interconnected complexity. 4) The porosity and permeability of microfractures, as well as the number of microfracture bars and permeability, indicate that the connectivity of coal bed is primarily caused by the microfracture system. By reconstructing the three-dimensional spatial structure of the #5 coal through multiple tests, the heterogeneous characteristics are quantitatively characterized.

Panax ginseng is a precious Chinese medicinal plant with a long growth cycle and high medicinal value. Therefore, it is of great significance to explore effective ways to increase its yield and main active substance content to reduce the cost of ginseng, which is widely used in food and clinical applications. Here, we review the key roles of microorganisms in the biological control of ginseng diseases, enhancement of ginseng yield, biotransformation of ginsenosides, and augmentation of ginsenoside bioactivity. The application of microorganisms in P. ginseng faces multiple challenges, including the need for further exploration of efficient microbial strain resources used in the cultivation of ginseng and biotransformation of ginsenosides, lack of microbial application in large-scale field cultivation of ginseng, and unclear mechanism of microbial transformation of ginsenosides. This review provides a deeper understanding of the applications of microorganisms in P. ginseng. [ABSTRACT FROM AUTHOR]

A gallium nitride (GaN) semiconductor is one of the most promising materials integrated into biomedical devices to play the roles of connecting, monitoring, and manipulating the activity of biological components, due to its excellent photoelectric properties, chemical stability, and biocompatibility. In this work, it was found that the photogenerated free charge carriers of the GaN substrate, as an exogenous stimulus, served to promote neural stem cells (NSCs) to differentiate into neurons. This was observed through the systematic investigation of the effect of the persistent photoconductivity (PPC) of GaN on the differentiation of primary NSCs from the embryonic rat cerebral cortex. NSCs were directly cultured on the GaN surface with and without ultraviolet (UV) irradiation, with a control sample consisting of tissue culture polystyrene (TCPS) in the presence of fetal bovine serum (FBS) medium. Through optical microscopy, the morphology showed a greater number of neurons with the branching structures of axons and dendrites on GaN with UV irradiation. The immunocytochemical results demonstrated that GaN with UV irradiation could promote the NSCs to differentiate into neurons. Western blot analysis showed that GaN with UV irradiation significantly upregulated the expression of two neuron-related markers, βIII-tubulin (Tuj-1) and microtubule-associated protein 2 (MAP-2), suggesting that neurite formation and the proliferation of NSCs during differentiation were enhanced by GaN with UV irradiation. Finally, the results of the Kelvin probe force microscope (KPFM) experiments showed that the NSCs cultured on GaN with UV irradiation displayed about 50 mV higher potential than those cultured on GaN without irradiation. The increase in cell membrane potential may have been due to the larger number of photogenerated free charges on the GaN surface with UV irradiation. These results could benefit topical research and the application of GaN as a biomedical material integrated into neural interface systems or other bioelectronic devices. [ABSTRACT FROM AUTHOR]

Space solar cells, have been providing a consistent supply of energy for various spacecraft for decades. Currently, the third‐generation solar cells, such as perovskite solar cells (PSCs) and organic solar cells, have demonstrated significant potential for space applications. However, their real performance in space environments is not yet clear. To assess crucial performance parameters, solar cells need to be calibrated under the standard space spectral irradiance before deployment in space. This is known as AM0 calibration. This review article focuses on the calibration techniques and methods for space solar cells. The topics covered include space environment and standard testing condition for solar cells, the measurements of key parameters for traditional solar cells, advancements in PSCs and organic solar cells for space applications, and a comprehensive review of diverse calibration methods. The discussion spans from near‐ground calibration to near‐space calibration and space calibration, encompassing approaches, key technologies, developmental milestones, and the respective merits of each calibration methods, especially focus on high altitude balloon calibration. Finally, the article addresses the challenges and future trends of space solar cell calibration based on the aforementioned discussions. [ABSTRACT FROM AUTHOR]

Gas diffusion electrodes (GDEs) mediate the transport of reactants, products and electrons for the electrocatalytic CO2 reduction reaction (CO2RR) in membrane electrode assemblies. The random distribution of ionomer, added by the traditional physical mixing method, in the catalyst layer of GDEs affects the transport of ions and CO2. Such a phenomenon results in elevated cell voltage and decaying selectivity at high current densities. This paper describes a pre-confinement method to construct GDEs with homogeneously distributed ionomer, which enhances mass transfer locally at the active centers. The optimized GDE exhibited comparatively low cell voltages and high CO Faradaic efficiencies (FE > 90%) at a wide range of current densities. It can also operate stably for over 220 h with the cell voltage staying almost unchanged. This good performance can be preserved even with diluted CO2 feeds, which is essential for pursuing a high single-pass conversion rate. This study provides a new approach to building efficient mass transfer pathways for ions and reactants in GDEs to promote the electrocatalytic CO2RR for practical applications. [ABSTRACT FROM AUTHOR]

Experiments on the titanium alloy Ti-1023（ Ti-10V-2Fe-3Al） work hardening and work hardening layer depth was studied by down or up milling,first milling or quadratic milling in a new tool or the wear tool. The results show that titanium alloy Ti-1023 is milled in carbide cutting tools,down milling in work hardening and work hardening layer depth is smaller than up milling,new tool in work hardening is smaller than wear tool,the work hardening layer depth is less than 25 μm in new tool; the work hardening layer depth is up to 81 μm and quadratic milling causes the machined surface softening in case of tool flank wear VB = 0. 3 mm.

In recent decades, there has been an increasing interest in the relation between lexical features and texts of psychological states. Previous studies demonstrated that some lexical features varied significantly among the texts of psychological states. However, the lexical features at the textual level have received little attention. This paper extends this work by examining the performance of quantitative linguistic indices in classifying texts of psychological issues. A large dataset of forum posts including texts of anxiety, depression, suicide ideation, and normal states were experimented with Machine Learning algorithms. The results revealed that the quantitative linguistic indices with Machine Learning algorithms achieved a high level of success in identifying psychological states. Meanwhile, some quantitative linguistic indices, namely, ALT and Writer's view, may extract adequate lexical features for classifying texts of different psychological states. The study is probably the first attempt that uses quantitative linguistic indices as lexical features to detect texts of psychological states, and the findings may contribute to our understanding of how accuracy may be enhanced in the identification of various psychological states. Finally, the implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Glucose sensing based on graphene conductance is investigated by the probe station and COMSOL Multiphysics. The current–voltage (I–V) results from the probe station show that there is a negative linear relationship between graphene conductance and glucose concentration. Using this relationship as the standard curve, the concentration of glucose on graphene can be obtained by measuring the conductance of graphene. The electrical behaviors of different glucose molecules on graphene simulated by COMSOL Multiphysics Toolbox indicate a scattering effect of glucose molecules on current and a more rapidly linear potential drop in the glucose region calculated from the equipotential line distribution, which is consistent with the experimental results. These results provide a new research perspective and method for the sensing of glucose and other biological substances. [ABSTRACT FROM AUTHOR]

This study conducted the solid fermentation process of Dioscorea nipponica using endophytic fungi C39 to determine the changes in the diosgenin concentration. The results revealed that endophytic fungi C39 could effectively biotransform the saponin components in D. nipponica. Moreover, the maximum increase in the diosgenin concentration reached 62.67% in 15 days of solid fermentation. MTT assay results demonstrated that the inhibitory effects of the fermentation drugs on four types of cancer cells (liver cancer cells (HepG2), stomach cancer cells (BGC823), cervical cancer cells (HeLa), and lung cancer cells (A549)) were better than those of the crude drugs obtained from D. nipponica. The chemical composition of the samples obtained before and after the biotransformation of D. nipponica was analyzed by UPLC-Q-TOF-MS. A total of 32 compounds were identified, 21 of which have been reported in Dioscorea saponins and the ChemSpider database and 11 compounds were identified for the first time in D. nipponica. The biotransformation process was inferred based on the variation trend of saponins, which included transformation pathways pertaining to glycolytic metabolism, ring closure reaction, dehydrogenation, and carbonylation. The cumulative findings provide the basis for the rapid qualitative analysis of the saponin components of D. nipponica before and after biotransformation. The 11 metabolites obtained from biotransformation are potential active ingredients obtained from D. nipponica, which can be used to further identify pharmacodynamically active substances. [ABSTRACT FROM AUTHOR]

Fusarium sp. C39 is an endophytic fungus of Dioscorea nipponica Makino. Symbiosis of Fusarium sp. C39 with Rhizoma Dioscoreae Nipponicae (RDN) can significantly increase the content of saponin, which provides a new approach for saponin production and reduces the pressure on natural sources of saponins. However, the underlying mechanism is not clear, limiting its application. In this study, the genome of Fusarium sp. C39 was sequenced, the gene functions were predicted via gene annotation, and the genome was compared to the genomes of four related species. Fusarium sp. C39 is predicted to encode many key enzyme genes involved in saponin synthesis, which could transform the mevalonate, isopentenyl pyrophosphate, and various intermediate compounds present in the RDN extract into saponins. The Fusarium sp. C39 genome contains specific genes that are conducive to its endophytic lifestyle and can provide abundant raw materials for saponin synthesis. Based on the genomic analysis, we proposed the mechanism by which Fusarium sp. C39 generates saponins and provides a theoretical basis for rapid, efficient, low‐cost production of saponins. [ABSTRACT FROM AUTHOR]

The success of human resource management is directly related to whether enterprises can stand in the fierce market competition. In the actual operation of enterprises, the human resource management faces various risks. Here, we take the human resource management evaluation standard as the research object and establish the human resource management benefit evaluation model through a SOM neural network. The training, studying, and testing processes of the model are performed. Besides, the human resource management evaluation system is built on the basis of this model. The evaluation research on the efficiency of human resource management has a good influence in many aspects. Researchers have tried to decipher the "black box" relationship between human resource management and organizational benefits, and an effective human resource management evaluation tool is obtained. This model involves both theoretical construction and empirical research. It is of great significance to summarize the progress and existing problems of current research and abroad and put forward some suggestions for future research. [ABSTRACT FROM AUTHOR]

Main conclusion: This work reviews recent advances in the pathways and key enzymes of steroidal saponins biosynthesis and sets the foundation for the biotechnological production of these useful compounds through transformation of microorganisms. Steroidal saponins, due to their specific chemical structures and active effects, have long been important natural products and that are irreplaceable in hormone production and other pharmaceutical industries. This article comprehensively reviewed the previous and current research progress and summarized the biosynthesis pathways and key biosynthetic enzymes of steroidal saponins that have been discovered in plants and microoganisms. On the basis of the general biosynthetic pathway in plants, it was found that the starting components, intermediates and catalysing enzymes were diverse between plants and microorganisms; however, the functions of their related enzymes tended to be similar. The biosynthesis pathways of steroidal saponins in microorganisms and marine organisms have not been revealed as clearly as those in plants and need further investigation. The elucidation of biosynthetic pathways and key enzymes is essential for understanding the synthetic mechanisms of these compounds and provides researchers with important information to further develop and implement the massive production of steroidal saponins by biotechnological approaches and methodologies. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is a common malignant tumor with high mortality and heterogeneity. Genetic mutations caused by driver genes are important contributors to the formation of the tumor microenvironment. The purpose of this study is to discuss the expression of cancer driver genes in tumor tissues and their clinical value in predicting the prognosis of HCC. Methods: All data were sourced from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), and Gene Expression Omnibus (GEO) public databases. Differentially expressed and prognostic genes were screened by the expression distribution of the cancer driver genes and their relationship with survival. Candidate genes were subjected to functional enrichment and transcription factor regulatory network. We further constructed a prognostic signature and analyzed the survival outcomes and immune status between different risk groups. Results: Most cancer driver genes are specifically expressed in cancer tissues. Driver genes may influence HCC progression through processes such as transcription, cell cycle, and T-cell receptor-related pathways. Patients in different risk groups had significant survival differences (p < 0.05), and risk scores showed high predictive efficacy (AUC>0.69). Besides, risk subgroups were also associated with multiple immune functions and immune cell content. Conclusion: We confirmed the critical role of cancer driver genes in mediating HCC progression and the immune microenvironment. Risk subgroups contribute to the assessment of prognostic value in different patients and explain the heterogeneity of HCC. [ABSTRACT FROM AUTHOR]

This study focused on the photocatalytic CO2 to methane (CH4) with H2O over NH2-MIL-125(Ti) under visible light. It shows that the CH4 yield of NH2-MIL-125(Ti) reaches as high as 15.83 µmol h−1 g catalysts - 1 , which is 82.6% higher methane (CH4) production than that of MIL-125(Ti). The amine functionalization promotes the CO2 adsorptions on amine groups and the electron transfer between Ti and organic clusters. The H2O acts as a good reductant in this catalytic system, which can provide the electrons and reduce the Ti4+ to Ti3+. This study provided a potential method to enhance the performance of photocatalytic CO2 conversion with H2O for the metal organic frameworks. [ABSTRACT FROM AUTHOR]

Knowledge gaps exist in how we implement aerobic exercise programs during the early phases post-stroke. Therefore, the objective of this review was to provide evidence-based guidelines for pre-participation screening, mobilization, and aerobic exercise training in the hyper-acute and acute phases post-stroke. In reviewing the literature to determine safe timelines of when to initiate exercise and mobilization we considered the following factors: arterial blood pressure dysregulation, cardiac complications, blood-brain barrier disruption, hemorrhagic stroke transformation, and ischemic penumbra viability. These stroke-related impairments could intensify with inappropriate mobilization/aerobic exercise, hence we deemed the integrity of cerebral autoregulation to be an essential physiological consideration to protect the brain when progressing exercise intensity. Pre-participation screening criteria are proposed and countermeasures to protect the brain from potentially adverse circulatory effects before, during, and following mobilization/exercise sessions are introduced. For example, prolonged periods of standing and static postures before and after mobilization/aerobic exercise may elicit blood pooling and/or trigger coagulation cascades and/or cerebral hypoperfusion. Countermeasures such as avoiding prolonged standing or incorporating periodic lower limb movement to activate the venous muscle pump could counteract blood pooling after an exercise session, minimize activation of the coagulation cascade, and mitigate potential cerebral hypoperfusion. We discuss patient safety in light of the complex nature of stroke presentations (i.e., type, severity, and etiology), medical history, comorbidities such as diabetes, cardiac manifestations, medications, and complications such as anemia and dehydration. The guidelines are easily incorporated into the care model, are low-risk, and use minimal resources. These and other strategies represent opportunities for improving the safety of the activity regimen offered to those in the early phases post-stroke. The timeline for initiating and progressing exercise/mobilization parameters are contingent on recovery stages both from neurobiological and cardiovascular perspectives, which to this point have not been specifically considered in practice. This review includes tailored exercise and mobilization prescription strategies and precautions that are not resource intensive and prioritize safety in stroke recovery. [ABSTRACT FROM AUTHOR]

To understand the influence of storage period on the quality of light-flavor Daqu, physicochemical and biochemical indices, as well as microbial communities of Daqu were analyzed by traditional and metagenomics methods. The results suggest that the moisture content of the Daqu samples are essentially invariant during the storage period; the acidity ascended slowly during the first 3 months, then descended; the saccharifying power of some samples began to decrease during the first 3 months. The diversity of the bacterial and fungal communities of some of the Daqu samples was found to decline to a minimum after storage for 3 months. On the basis of the variations in primary indices of the Daqu samples, it was deemed acceptable to store samples for 3 months before use for light-flavor Daqu. This is the first report of Daqu quality being estimated during storage by physicochemical, biochemical, and microbial indices, and it provides a theoretical foundation for the quality evaluation of Daqu during storage and use. [ABSTRACT FROM AUTHOR]

Radar bias estimation is an important part of a multisensor tracking system. Because the radar bias models in current efforts are not sufficiently accurate, the bias estimation accuracy is not satisfied. First, a general radar bias model, in which the importance of the sensor-target pair-related bias is emphasized, is proposed in this paper. Moreover, the target-sensor pair-related bias is considered on the grounds of the impact of atmospheric refraction on the electromagnetic wave propagation path. Second, by using the augmented state vector with the target state and radar bias, a dynamic equation and measurement equation under the IMM framework are obtained. Last, the IMM-UKF estimator is utilized to obtain the target state and radar bias simultaneously. The numerical simulations show that the accuracy of the bias estimation together with the target states estimation can be improved via the proposed radar bias model. [ABSTRACT FROM AUTHOR]

The processing of Juglans mandshurica Maxim. is important to reduce its toxicity and enhance its efficacy. Simple, efficient, and sensitive ultra-high performance liquid chromatography coupled with a time-of-flight mass spectrometry based chemical profiling approach was proposed to rapidly evaluate the chemical difference between fresh and dry samples. Under the optimized ultra-high performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry conditions, 81 significantly different compounds were rapidly discovered using principal component analysis, and then tentatively identified by comparison with reference substances or inferred through mass spectral fragment ion analysis and literature data. These compounds included 35 naphthoquinones, 11 diarylheptanoids, nine flavonoids, eight triterpenes, 12 phenolic acids, and six aliphatics. The results demonstrated that chemical reactions occurring during processing could be used to elucidate the processing mechanism of Juglans mandshurica Maxim. This study provides a novel approach to identifying complicated components of various complex mixtures in fresh-raw and dry-processed traditional Chinese medicines, which could be used as a valid analytical method to further understand the processing mechanisms of these medicines, as well as providing intrinsic quality control of the medicines and their processed products. [ABSTRACT FROM AUTHOR]

In order to find a suitable method for detecting the microbe index of Daqu for Chinese liquor brewing, during the regular production of Daqu, the phospholipid fatty acid (PLFA) profiles of Daqu for light-fragrant Chinese liquor were investigated. Three types of Daqu clearly showed different features. The PLFA 18:3 w 6c (3, 6, 9), as one of the biomarkers for fungi, was the highest in the Houhuoqu samples, the lowest in the Hongxinqu samples and moderate with fluctuations in the Qingchaqu samples. The PLFA 18:1 w 9c, another biomarker for fungi, was only detected in the Hongxinqu samples with a steady content. The ratio of the fungi to bacteria of Hongxinqu was 11:20, which was significantly higher than in the Qingchaqu and the Houhuoqu samples. Principal component analysis found that most of the variations in the PLFA patterns were due to the different Daqu types. Variances analysis found that some PLFAs had the potential to be used as representative biomarkers for each type of Daqu. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]