84 research outputs found

    Virtual prototyping-based fatigue analysis and simulation of crankshaft

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    Explanation of the Patterns, Spatial Relationships, and Node Functions of Biodiversity and Island: An Example of Nature Reserves in Guizhou, Southwest China

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    Biological habitat islanding occurs with the expansion of human activities. Nature reserves are biodiversity hotspots and sources of biodiversity diffusion. To explore the geographical causes of biodiversity and the impact of habitat island on biodiversity, we studied the spatial network relationships of biodiversity in nature reserves and the spatial characteristics of ecological corridors in reserves using various biodiversity indicators and ecological factors of important nature reserves, digital elevation models, and information regarding the land use types in Guizhou Province. Data were analyzed using canonical correspondence analysis and the lowest-cost analysis method. The results of this study showed that the factors that determine the biodiversity of the dominant region are heat, moisture, rock type, parent rock, and soil type. The nature reserves can be divided into seven categories according to the characteristics and ecological factors of the biodiversity network. We identified ecological corridors for biodiversity diffusion and classified them by levels of importance according to their degree of corridor composition

    Multi-component solvent-free cascade reaction of 2-cyanoacetamides: regioselective synthesis of pyridin-2-ones bearing quaternary centers

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    A novel protocol has been constructed for the synthesis of four types of pyridin-2-ones via multicomponent solvent-free cascade reactions of 2-cyanoacetamides, various ketones, and acetone.</p

    Prostate Cancer Incidence and Mortality: Global Status and Temporal Trends in 89 Countries From 2000 to 2019

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    AimsTo evaluate current status of prostate cancer incidence and mortality worldwide, and compare the global trends of incidence and mortality in the past two decades and in the most recent period.MethodsData on the incidence and mortality of prostate cancer for 174 countries in 2020 were obtained from the GLOBOCAN 2020 database, and associations with the human development index (HDI) were evaluated. Data for trend analyses in 89 countries from 2000 to 2019 were retrieved from the Global Burden of Disease 2019 platform. Age standardized incidence rate (ASIR) and mortality rate (ASMR) were calculated by using the Segi's population. The average annual percent changes (AAPC) of ASIRs and ASMRs were evaluated by joinpoint regression analysis.ResultsA total of 1 414 259 new cases of prostate cancer and 375 304 related deaths were reported in 2020 globally. HDI was positively correlated with ASIRs (P &amp;lt; 0.001) and negatively correlated with ASMRs (P &amp;lt; 0.001). In the past two decades, ASIRs have been increasing in 65 countries, stable in 15 countries and decreasing in 9 countries, and ASMRs have been increasing in 19 countries, stable in 25 countries and decreasing in 45 countries, respectively. In the most recent period, 44 countries have increasing ASIRs, and 32 countries have decreasing ASMRs, respectively. For instance, in the United States of America, the AAPC of ASIRs significantly decreased by 0.62% and ASMRs significantly decreased by 1.22% from 2000 to 2019, while the AAPC from 2015 to 2019 significantly increased by 0.49% for ASIRs and significantly increased by 0.48% for ASMRs.ConclusionThe magnitude of increasing incidence and decreasing mortality of prostate cancer is attenuated in the recent period. Further study is needed to analyze the absolute effect of risk factors, PSA screening and treatment.</jats:sec

    Prognostic and Immunological Value of GNB4 in Gastric Cancer by Analyzing TCGA Database

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    Background. Gastric cancer (GC) represents a universal malignant tumor of the digestive system. Stromal and immune cells belong to two main nontumor components exerting a vital function in the tumor microenvironment. Methods. Based on TCGA database, this study downloaded clinical information and gene profiles of GC. The ESTIMATE algorithm was adopted for evaluating the score of immune-infiltrating cells. This work employed Sangerbox to explore the differentially denoted genes (DEGs) related to stromal, immunity, and prognosis. Besides, the STRING database was involved in order to detect the association among the proteins. The MCODE module of Cytoscape software was used to screen key genes. Oncomine and GEPIA databases were used, aiming to study the differences in key genes in healthy gastric mucosa and GC. At last, we adopted TISDIB and TIMER databases for analyzing the association of guanine nucleotide binding protein subunit-4 (GNB4) between gastric cancer and tumor immune cells. qRT-PCR was applied for exploring differential GNB4 expression between GC and normal gastric mucosa and investigating the relation of GNB4 with tumor-infiltrating lymphocytes (TILs). Results. Patients undergoing a great stromal score exhibited worse prognostic outcome, and cases having a low immune score had better prognosis. Overall, altogether 656 genes were upregulated with 5 genes being downregulated, which were matrix immune-related differential genes. Furthermore, 18 genes were screened as hub genes on the basis of the univariate Cox risk model of TCGA database (82 differential genes predicted poor GC survival). Oncomine and GEPIA databases revealed that GNB4 expression in gastric cancer was obviously higher in comparison with that in normal gastric mucosa. The GSEA, TISDIB, and TIMER databases revealed that GNB4 is involved in various tumor signal pathways and immune and metabolic processes. qRT-PCR demonstrated that GNB4 expression in gastric cancer was notably higher in comparison with that in normal gastric mucosa, showing significant association with matrix TILs. Conclusion. The selected key gene GNB4 is a potential biomarker to guide the immunotherapy of gastric cancer.</jats:p

    Pyrene exposure influences the thyroid development of Sebastiscus marmoratus embryos

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    National Natural Science Foundation of China [20977071]; Ocean Public Welfare Scientific Research Special Appropriation Project [201005016]; Fundamental Research Funds for the Central Universities [2012121045]Thyroid hormones play crucial roles in regulating development, morphogenesis, growth, and behavior in fishes. Some environmental pollutants have adverse effects on either development or function of the thyroid gland in fish. However, there are few reports on the effects of polycyclic aromatic hydrocarbons (PAHs) on fish thyroid. In the present study, rockfish (Sebastiscus marmoratus) embryos were exposed to pyrene (Py) for 5 days at the concentrations of 0.5, 5, and 50 nmol/L. The results showed that Py exposure decreased the expression of thyroid primordium markers, Pax2.1 and Nk2.1a as detected by quantitative PCR and in situ hybridization, and reduced the concentration of T-3, but not T-4. Thyroid receptor genes (TR alpha and TR beta) expression was down-regulated by Py. At the same time, Py exposure impaired the expression of thyroid development related genes. Fgfr2 and Hoxa3a expression, and altered the mRNA levels of thyroid function related genes, Deio1, Ttr, and Tg. In conclusion, the results demonstrated Py exposure inhibited thyroid development and influenced the function of thyroid system in rockfish embryos. (c) 2012 Elsevier B.V. All rights reserved
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