Application of BP Neural Network Algorithm in Sustainable Development of Highway Construction Projects

AbstractHighway construction project does not exist for its own, but also to meet the needs of the society. Its development strategy should be based on the overall goal of the society, not just for its own. Therefore, the sustainable evaluation of the highway construction should be considered from the two parts of sustainability of social needs and economic development. In this paper, using the BP neural network algorithm, through the analysis of sustainable development of the following four areas in road construction: economics, environmental resources, operations, management systems and policy, the author studies the sustainable development evaluation of highway construction project

Too Big or Too Small? The Threshold Effects of City Size on Regional Pollution in China

The relationship between urban agglomeration and environmental pollution was checked using the balanced panel data of 285 cities in China from 2003 to 2016 and applying the fixed-effect model and the threshold effect model. This showed that: (1) the relationship between urban agglomeration (represented by city size) and environmental pollution is not linear but an inverted U-shape. As long as the GDP is less than 800,370 million RMB, the expansion of city size is not conducive to reducing pollutant emissions. When GDP is less than 41,641 million RMB, the influence of city expansion on environmental pollution is relatively less. When GDP is higher than 800,370 million RMB, the city expansion may reduce pollutant emission. (2) The city size is not too big but is in fact too small. Only 18 cities experienced the inverted U-shape with the expansion of their city size, causing the gas and water pollutant emissions to decrease. (3) For cities in an urban agglomeration, environmental pollution can be reduced by expanding the city size through coordinated development of urban agglomeration. In conclusion, for most large cities in urban agglomerations in China, the city size is not too large but too small

Synthesis and Mechanical Properties of VB_2 Coatings by Pulsed Magnetron Sputtering

The VB_2 coatings were synthesized by pulsed magnetron co-sputtering on the substrates of Si(100), glass and M2 tool steel, pre-deposited with Ti transition layers. The impact of the frequency of power-supply on the microstructures and mechanical properties of the VB2 coatings was investigated. The VB_2 coatings were characterized with X-ray diffraction,scanning electron microscopy, atomic force microscopy and conventional mechanical probes. The results show that depending on the frequency,the VB_2 coatings possess improved surface mechanical properties, such as higher hardness, better wear-resistance and lower friction coefficient. As the frequency increased, the surfaces with big columnar-structured grains turned into amorphous-like surfaces with smaller grains and reduced roughness. Grown at 250 kHz, the preferentially oriented, smooth and compact VB2 coatings had a surface hardness of 43 GPa,and a wear-rate of 7.8 * 10~(-16) m3/N m,300 times lower than that of M2 tool steel

Clinical features of anemia in membranous nephropathy patients: a Chinese cohort study

AbstractBackground Anemia is a common complication in patients with progressive chronic kidney disease. This cohort study evaluated the prevalence, clinical features and prognosis of membranous nephropathy (MN) with anemia.Methods We retrospectively analyzed a cohort of MN patients diagnosed using renal biopsy between February 2012 and February 2018. The clinical and pathological characteristics at baseline were recorded, and the outcomes (hemoglobin, proteinuria and renal function) during follow-ups were also evaluated. Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors for anemia in MN patients. The MN patients were divided according to the therapeutic effect they experienced as follows: without-anemia, completely corrected anemia, standard anemia treatment and nonstandard anemia treatment groups. We compared the rate of complete remission of MN and renal end-point events among the four groups.Results The median age of 483 patients was 42.43 (26.59, 50.20) years at the time of MN diagnosis. The prevalence of anemia at baseline was 23.81%, and the cumulative prevalence was 50.72%. There were 133 cases of mild anemia, 103 cases of moderate anemia and 9 cases of severe anemia; in addition, there were 228 cases of normocytic anemia and 17 cases of microcytic hypochromic anemia. Multivariate logistic regression indicated that acute renal tubule injury >5% (OR = 1.634, 95% CI 1.034, 2.581; p = 0.035), total protein level (OR = 0.949, 95% CI 0.923, 0.975; p < 0.001), cholesterol level (OR = 0.833, 95% CI 0.749, 0.926, p = 0.001), hypokalemia (OR = 2.612, 95% CI 1.227, 5.560, p = 0.013) and hypophosphatemia (OR = 2.653, 95% CI 1.303, 5.403, p = 0.007) were independent risk factors for anemia in MN patients. The complete remission rate of MN patients without anemia was significantly higher than that of anemia patients who exhibited treatment failure. The incidence of renal endpoint events was different among the four groups.Conclusion The anemia experienced by MN patients is mainly mild and moderate, normocytic anemia. The pathological features of acute renal tubular injury and clinical nutritional status are independent risk factors for anemia. There were differences in renal prognosis among anemia patients with different treatment outcomes

Adequate enrichment of extracellular vesicles in laboratory medicine

Abstract Extracellular vesicles (EVs) and their clinical applications have been recognized as one of the most fast‐growing and promising fields. Numerous groups including us have expressed their concerns on the idea of isolating “pure” EVs for different purposes, as there are no specific markers to date that can examine the exact EV purity. Typically, major instrument need and EV yielding loss are primary compensations of getting EVs with higher purity. As such, especially in biomarker‐based clinical tests, ceaseless efforts for obtaining more pure EV are worth of discussion. We here propose alternative philosophy to tone down the importance of purity, but to emphasize the significance in clinical laboratory medicine to measure EVs obtained by well‐controlled isolation methods. As a result, EVs are enriched to the adequate degree to meet certain clinical applications such as disease diagnosis and/or prognosis. In this review, we will justify the adequate enrichment rationale with advances of EV definitions, markers and contaminants, EV isolation methods, as well as the conclusions acquired from clinical research using less pure but ease‐to‐operate EV isolation methods

STUDY ON RHEOLOGICAL BEHAVIOR AND CONSTITUTIVE MODEL OF TA17 TITANIUM ALLOY AT HIGH STRAIN RATE

The quasi-static(Strain rate of 0.001 s-1～0.01 s-1) and dynamic(Strain rate of 1000 s-1 ～ 5 000 s-1) compression tests of TA17 titanium alloy were conducted on at 25℃. The strain hardening characteristics and the mechanism of strain rate on its rheological behavior were studied, and the rheological characteristics under high strain rates were quantitatively studied by means of strain hardening index（n） and strain rate sensitivity index（m）. Based on the dynamic rheological characteristics of TA17 titanium alloy and considering the influence of the coupling between strain and strain rate on its flow stress, a new J-C constitutive model is constructed. based on the obtained experimental data, the model parameters are identified, the predicted values of the model are compared with the experimental data, and the two parameters of correlation coefficient（R） and average absolute relative error are introduced to evaluate the prediction accuracy of the constructed constitutive model.The results show that TA17 titanium alloy exhibits obvious strain hardening, strain rate strengthening and strain rate plasticizing effects, and its rheological behavior is dominated by strain, strain rate and the coupling between them. The strain hardening index decreases with the increase of strain and strain rate, while the strain rate sensitivity index increases with the increase of strain rate, and decreases with the increase of strain. The correlation coefficient（R） of constructed constitutive model is 0.997 7 and the average absolute relative error is 0.27%

Comparative ligandomics implicates secretogranin III as a disease-restricted angiogenic factor in laser-induced choroidal neovascularization

Choroidal neovascularization (CNV) is a leading cause of vision loss in the elderly. All approved anti-angiogenic drug therapies for CNV target vascular endothelial growth factor (VEGF) but confer limited efficacy. Identification of other CNV-related angiogenic factors will facilitate the development of VEGF-independent alternative therapies. Here, we applied comparative ligandomics to live mice with or without laser-induced CNV for global mapping of CNV-selective endothelial ligands. Secretogranin III (Scg3) previously identified by the same approach as a diabetes-restricted angiogenic factor was mapped with a more than 935-fold increase in binding to CNV vessels compared to healthy choriocapillaris. A novel in vivo ligand binding assay independently confirmed a marked increase in Scg3 binding to CNV vessels, whereas VEGF showed no increase in CNV-selective binding. A new technique of functional immunohistochemistry allowed the visualization and confirmed the increase in in vivo Scg3 binding to CNV vasculatures, including CNV microcapillaries with detailed vascular structures, which was blocked by anti-Scg3 humanized antibody Fab fragment (hFab). The hFab effectively alleviated laser-induced CNV with an efficacy similar to the anti-VEGF drug aflibercept. Homozygous deletion of the Scg3 gene in mice significantly reduced the severity of CNV. Furthermore, the therapeutic activity of anti-Scg3 hFab, but not aflibercept, was abolished in Scg3 mice, suggesting the Scg3-dependent nature of the hFab-mediated therapy. These findings suggest that Scg3 plays an important role in CNV pathogenesis and is a promising disease-restricted angiogenic factor for ligand-guided disease-targeted anti-angiogenic therapy of CNV