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BACKGROUND With the increased attention paid for the construction of ecological civilization, a comprehensive survey of natural resources is imperative, and new requirements for biological reference materials have also been put forward. At present, relevant research work has been widely carried out. The comprehensive investigation of natural resources, agricultural products and food safety evaluation all need to accurately test the element composition of biological samples, and biological reference materials are needed as the basis for the comparison and traceability of biological components. The demand for biological matrix reference materials has increased significantly. As one of the main foods, the food safety of rice has been paid more and more attention. It is of great practical significance to carry out accurate analysis of the chemical components in rice. Therefore, the demand for rice is particularly prominent, but the rice reference materials for composition analysis are still lacking. OBJECTIVES To develop rice certified reference material (GBW10010a) and compare it with the data characteristics of GBW10010. METHODS The rice certified reference material (GBW10010a) was prepared in strict accordance with relevant specifications. The collected candidates were prepared through coarse crushing, drying, fine crushing, sieving, blending and other steps. The particle size distribution was detected by BT-9000ST laser particle size analyzer. 15 bottle samples were randomly selected and homogeneity testing was carried out by ICP-MS and ICP-OES, etc. The data were statistically calculated by one-way ANOVA, indicating good homogeneity of the samples. The long-term stability of the standard material under the specified storage conditions was investigated. The linear model was used to evaluate the stability of the sample. The determination of 60 components was carried out by means of ICP-MS, ICP-OES, AFS, COL, VOL, XRF, IC and other Analytical test methods. RESULTS The rice reference material prepared in this research has diverse fixed value components, accurate and reliable measurement values, and meet the requirements of national first-level reference material. GBW10010a has a total of 54 main trace elements. 39 elements have certified values and uncertainties and 15 elements only have reference values. The content of heavy metal elements such as As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Zn in GBW10010a decreased significantly, among which Cd, Cu, and Zn decreased by about 39%, 43% and 38.7%, respectively. CONCLUSIONS To a certain extent, the values reflects the improvement of farmland ecological environment. Compared with the original GBW10010, the total number of certified value elements has increased by 6 items, including Ag and Nb (Nb gives reference values). Moreover, the uncertainty of each element is reduced, including biological-related elements Al, Cd, Cu, Fe, K, Mg, Mo, Na, P, Pb, Se, and Zn. The reduction indicates the technological advancement of the geological analysis and the improvement of the certified value level. In addition, the content of heavy metal elements in GBW10010a decreased significantly, reflecting the improvement of farmland ecological environment. The designated elements of the reference materials cover most of the main and trace elements with biological effects, and are suitable for the calibration of analytical instruments, evaluation of analytical methods, and monitoring analytical quality during agricultural ecological environment geochemical surveys and evaluation, biological sample analysis, agricultural product quality and food safety evaluation.

Abstract Identifying novel prognostic biomarkers for hepatocellular carcinoma (HCC) and then, develop an effective individualized treatment strategy remain extremely warranted. The prognostic role of sulfiredoxin‐1(SRXN1), an antioxidant enzyme, remains unknown in HCC. This study aimed to explore the prognostic implications of SRXN1 in HCC patients after partial hepatectomy. The expression of SRXN1 in HCC and normal tissue were analyzed using the patients from the public databases and Zhongshan Hospital. The Cox regression, Kaplan‐Meier survival analysis, and time‐dependent receiver operating characteristic curves were performed to identify the predictive role of SRXN1 expression on HCC patients. A prognostic nomogram based on SRXN1 expression was constructed and validated to further confirm the predictive power of SRXN1 as a prognostic biomarker. Finally, functional enrichment analysis and protein‐protein interaction network analysis of SRXN1 and its associated genes were conducted. The results showed that SRXN1 was upregulated in HCC samples compared with the normal liver tissues. Patients with SRXN1 upregulation had shorter survival time. SRXN1 overexpression was significantly correlated with advanced clinicopathological parameters. The prognostic nomogram based on SRXN1 expression was proved to be more accurate than routine staging systems for the prediction of overall survival. Protein‐protein interaction network analysis demonstrated the first neighbor genes of SRXN1 mainly participated in response to oxidative stress. In brief, SRXN1 could be a prognostic biomarker for the management of HCC.

BACKGROUND Selenium is an important, essential element of life. The development of selenium-enriched agricultural products is a safe and effective way to increase the level of human selenium intake in China. The evaluation and utilization planning of selenium-enriched land resources are important aspects of land quality geochemical surveys, to serve the development of characteristic agricultural products and to overcome poverty. OBJECTIVES To improve the methodology for selenium-enriched land assessment and to develop more effective and safe land-use planning methods. METHODS The research results on selenium content in soil and crops, the origin of soil selenium, the soil selenium occurrence and its bioavailability factors, the soil-crop system selenium absorption and transport, and the interaction between selenium and heavy metal cadmium were reviewed in this article. RESULTS The geochemical background of selenium in top soils in China was 0.2mg/kg, significantly lower than the average in world soils (0.4mg/kg). Generally, the soils had a low selenium level, and it was believed that the use of 0.40mg/kg selenium as a selenium-enriched soil standard had a strong scientific basis. Selenium in soils was mostly from a geological setting, however, in some cases anthropogenic activities may be an important source of soil selenium. The genetic mechanism of selenium-enriched soils can be categorized as high geological background, weathering accumulation and anthropogenic input as well as a multi-factor combination. The association of selenium with cadmium and other heavy metals was pervasive because of similar geochemical behavior and geological origin. The species and bio-availability of selenium in soils were mainly controlled by its source and soil physic-chemical properties such as pH, Eh, and contents of organic matter, iron oxides and aluminum oxides. In turn, these factors affect the availability of selenium-enriched land and became the theoretical basis and considerations for formulating local standards for selenium-enriched soil. The accumulation ability of selenium varied greatly between crop cultivars. Selection native crop types with higher selenium accumulation ability and low accumulation with Cd as well as other toxic metals was of practical meaning. Some existing selenium-enriched agricultural product standards did not fully consider the purpose of human selenium supplementation, and there were problems such as poor coordination between standards. It was urgent to strengthen the formulation of selenium-enriched agricultural product standards. CONCLUSIONS Selenium-enriched land suitability assessment, local selenium-enriched soil standard establishment and selenium-enriched crop plantation planning should consider the concentration of selenium and heavy metals in soils, their source and genesis, bio-availability and influencing factors, transport and accumulation in soil-crop system, the synergistic or antagonistic effects between selenium and other chemicals such as cadmium, as well as plantation suitability of crop cultivars under local climate, soil conditions and landscape. According to the availability of selenium-enriched land resources, classification, zoning, scientific planning and reasonable planting management are carried out. In order to meet the needs of investigation and evaluation of selenium-enriched land resources, availability analysis, and research on the health effects of selenium-enriched agricultural products, it is recommended to strengthen the research and application of extraction, separation, analysis, and determination methods for soil and crop selenium content and species.

Ammonium salt crystallization corrosion failure is an essential problem in the failure of high-pressure hydrogenation heat exchangers. The crystallization equilibrium curves of NH4Cl and NH4HS under different pressures were established according to the ammonium salt crystallization process in the high-pressure hydrogenation heat exchange unit, and the crystallization equilibrium temperatures of NH4Cl and NH4HS were obtained based on Aspen Plus. In addition, a prediction model for the crystallization temperature of ammonium salt was established, then the relationship between crystallization temperature and rate of ammonium salts was elaborated. The results indicate that the initial crystallization temperatures of NH4Cl and NH4HS are respectively 198.95°c and 134.45°c when the system pressure is 10MPa, and the temperature is 433.15K. The maximum crystallization rate of NH4Cl and NH4HS occur at the initial crystallization temperature, respectively 0.104kg/h and 29.23kg/h. The crystallization rate of NH4HS is three orders of magnitude higher than that of NH4Cl.

Recent research has shown the advantages of incorporating multisource geospatial data into the classification of urban functional zones (UFZs), particularly remote sensing and social sensing data. However, the effects of combining datasets of varying quality have not been thoroughly analyzed. In addition, human mobility patterns from social sensing data, which capture signals of human activities, are often represented by origin-destination pairs, thus ignoring spatial relationships between UFZs embedded in mobility trajectories. To address the aforementioned issues, this study proposed a graph-based UFZ classification framework that fuses semantic features from high spatial resolution (HSR) remote sensing images, points of interest, and GPS trajectory data. The framework involves three main steps: (1) High-level scene information in HSR remote sensing imageries was extracted through deep neural networks, and multisource semantic embeddings were constructed based on physical features and social sensing features from multiple geospatial data sources; (2) UFZ mobility graph was constructed by spatially joining trajectory information with UFZs to construct topological connections between functional parcel segments; and (3) UFZ segments and multisource semantic features were transformed into nodes and embeddings in the mobility graphs, and subsequently graph-based models were adopted to identify UFZs. The proposed framework was tested on Zhuhai and Singapore datasets. Results indicated that it outperformed traditional classification methods with an overall accuracy of 76.7% and 84.5% for Zhuhai and Singapore datasets, respectively. The proposed framework contributes to literature in heterogeneous data fusion and is generalizable to other UFZ classification scenarios where human mobility patterns play a role.

Research has proven that light treatment, specifically red light radiation, can provide more clinical benefits to human health. Our investigation was firstly conducted to characterize the tissue morphology of mouse breast post 660 nm laser radiation with low power and long-term exposure. RNA sequencing results revealed that light exposure with a higher intervention dosage could cause a number of differentially expressed genes compared with a low intervention dosage. Gene ontology analysis, protein–protein interaction network analysis, and gene set enrichment analysis results suggested that 660 nm light exposure can activate more transcription-related pathways in HC11 breast epithelial cells, and these pathways may involve modulating critical gene expression. To consider the critical role of the Wnt/T-catenin pathway in light-induced modulation, we hypothesized that this pathway might play a major role in response to 660 nm light exposure. To validate our hypothesis, we conducted qRT-PCR, immunofluorescence staining, and Western blot assays, and relative results corroborated that laser radiation could promote expression levels of β-catenin and relative phosphorylation. Significant changes in metabolites and pathway analysis revealed that 660 nm laser could affect nucleotide metabolism by regulating purine metabolism. These findings suggest that the Wnt/β-catenin pathway may be the major sensor for 660 nm laser radiation, and it may be helpful to rescue drawbacks or side effects of 660 nm light exposure through relative interventional agents.

Intractable functional constipation (IFC) is the most severe form of constipation, but its etiology has long been unknown. We hypothesized that IFC is caused by refractory infection by a pathogenic bacterium. Here, we isolated from patients with IFC a Shigella species--peristaltic contraction-inhibiting bacterium (PIB)--that significantly inhibited peristaltic contraction of the colon by production of docosapentenoic acid (DPA). PIB colonized mice for at least 6 months. Oral administration of PIB was sufficient to induce constipation, which was reversed by PIB-specific phages. A mutated PIB with reduced DPA was incapable of inhibiting colonic function and inducing constipation, suggesting that DPA produced by PIB was the key mediator of the genesis of constipation. PIBs were detected in stools of 56% (38 of 68) of the IFC patients, but not in those of nonIFC or healthy individuals (0 of 180). DPA levels in stools were elevated in 44.12% (30 of 68) of the IFC patients but none of the healthy volunteers (0 of 97). Our results suggest that Shigella sp. PIB may be the critical causative pathogen for IFC, and detection of fecal PIB plus DPA may be a reliable method for IFC diagnosis and classification., Introduction Chronic constipation (CC) is a common and multifactorial disorder characterized by reduced bowel movement, hard stools, and excessive fecal straining (1-3). CC may be primary (idiopathic) or associated with [...]

C19H28N6O7S, monoclinic, P21 (no. 4), a = 8.1573(1) Å, b = 17.4823(1) Å, c = 9.1162(1) Å, β = 116.432(1)°, V = 1164.14(2) Å3, Z = 2, Rgt(F) = 0.0273, wRref(F2) = 0.0732, T = 170(2) K.

The gearbox is a crucial component of the power transmission system in high-speed trains, and realistically calculating its natural frequency is vital in avoiding system resonance. In recent decades, numerical techniques have become essential in designing engineering structures, and the finite element method (FEM) has gained widespread recognition and acceptance for its robustness and effectiveness. However, the FEM technique using linear 4-node tetrahedral elements (T4) performs poorly, leading to low accuracy and unreliable results. Consequently, complex hexahedral or second-order elements are often required for better performance. In this paper, we employ the smoothed finite element method (S-FEM), which combines the gradient smoothing technique with the standard FEM to improve calculation accuracy while still using linear tetrahedral elements. We apply S-FEM to accurately obtain the natural frequencies and mode shapes of a high-speed train gearbox using automatically generated linear tetrahedral elements. A test of tolerance to mesh distortion is also carried out on the gearbox. The results demonstrate that S-FEM can significantly enhance the computational accuracy of low-order 4-node tetrahedral elements without altering the mesh topology. It is expected that S-FEM can be an alternative to FEM in the modal analysis of complex structures in the railroad industry. [ABSTRACT FROM AUTHOR]