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The agronomic technology of whole plastic-film mulching on double ridges has been widely promoted in the arid region of northwest China, which has caused serious residual film pollution in the field. Mechanized residual plastic-film collecting is the main way, but this way of residual plastic-film collecting is more complicated. To prove the effect of typical film-lifting parts on residual plastic-film collecting performance by a numerical simulation method, further evaluate and select the working parts suitable for residual plastic-film collecting and improve the collecting efficiency, virtual whole plastic-film mulching on double ridges needs to be established. In this study, the film-lifting parts and the double ridge with flexible, deformable, mulching, film interaction model was developed using the discrete element method (DEM). The interaction model was used to simulate the operation process of a typical third-order shovel, hug plate and elastic teeth film-lifting parts. Furthermore, the operation resistance, seed bed disturbance and collecting residual film form under different working conditions were analyzed. The simulation results show that: the disturbance of the ridge from strong to weak is the third-order shovel, elastic teeth and hug plate film-lifting parts; the crushing of the ridge soil from strong to weak is the elastic teeth, the hug plate and the third-order shovel film-lifting parts; the collecting film from strong to weak is the hug plate, elastic teeth and the third-order shovel film-lifting parts; the median value of the horizontal force fluctuation range of the ridge soil on the film-lifting parts is increased, and the increase trend is from large to small in the third-order shovel, elastic teeth and hug plate film-lifting parts (the third-order shovel is 5250 N, 6250 N and 7750 N; the hug plate is 3250 N, 3500 N and 4000 N; and the elastic teeth are 4150 N, 4550 N and 5450 N). The comparative analysis results show that the hug plate film-lifting parts are more suitable for the residual-film collecting of whole plastic-film mulching on double ridges. Field trials were carried out to verify the operational effectiveness of the hug plate film-lifting parts. The results show that the morphological changes of the recovered residual film and the simulated mulching film during the operation of the hug plate-type residual film machine, and the distribution of the surface properties of the ridge after the residual-film collecting are basically consistent with the simulation results, and the film pick-up rate of hug plate film-lifting parts reaches 95.20%, and the established discrete element interaction model is reliable. The research results can provide reference for the research and development of full film duopoly furrow-mechanized residual film-collecting agricultural equipment in the arid region of northwest China. [ABSTRACT FROM AUTHOR]

Building resilient cities has become a hot topic in urban planning and risk management. Adopting the perspective of the social‐ecological system (SES), this paper incorporated economy–ecology–society–infrastructure into an integrated research framework and established a system for assessing the urban resilience development level. The entropy weight method was combined with a cloud model to systematically calculate and classify the resilience of 31 provinces (cities) in China. The evaluation results show that (1) the overall level of urban resilience in China was relatively low; the regional analysis showed that (2) the urban resilience of the eastern region was higher than the national average and that of the central and western regions, and from the perspective of the four subsystems, (3) the comprehensive development of each subsystem was the key to improving urban resilience. Finally, five improvement strategies were proposed to provide ideas for enhancing urban SES ability. [ABSTRACT FROM AUTHOR]

Maintenance strategies are commonly used for repairable products or items to reduce the warranty cost in the warranty coverage. This study proposes a new warranty maintenance strategy for two-dimensional extended warranty (EW) based on dynamic usage rate. Unlike previous studies that assumed a constant usage rate, the present study regards the consumer usage rate as dynamic in the two-dimensional EW coverage. A maintenance model is constructed to determine the optimal maintenance degree of warranty claim points and help service providers accurately estimate and reduce warranty cost. A numerical example of an automobile made in China is discussed to demonstrate the effectiveness of the proposed model. The formulated model can effectively reflect the changes in the consumer usage rate and thus helps service providers develop an accurate maintenance strategy. Meanwhile, the developed model can better reduce warranty cost compared with maintenance strategies with minimal repair. [ABSTRACT FROM PUBLISHER]

Summary: Background Esophageal cancer is a very common malignant tumor in China, especially esophageal squamous cell carcinoma (ESCC), but there is currently no effective treatment for patients after first-line chemotherapy failure. Apatinib has shown promising outcomes in treatment with various solid tumors. Objectives To evaluate the clinical efficacy and safety of apatinib combined with S-1 in the treatment of advanced ESCC patients after first-line chemotherapy failure. Methods In this prospective study, fifteen patients with advanced ESCC who failed first-line chemotherapy were enrolled from Nov 2016 to Apr 2019. Patients received the combination therapy with apatinib (250-500 mg, once daily) plus S-1 (40–60 mg based on body surface area, twice daily). Primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), disease control rate (DCR) and objective response rate (ORR). Adverse events (AEs) were recorded to evaluate the safety. Results A total of 12 patients were included in the efficacy analysis. The median PFS was 6.23 months, and the median OS was 8.83 months. Two (16.67%) patients achieved partial remission, 9 patients (75.00%) achieved stable disease and 1 (8.33%) patient achieved progressive disease. DCR and ORR was 91.67%and 16.67%, respectively. Most frequent AEs were hypertension, myelosuppression, weakness, hemorrhage, hand-foot syndrome, total bilirubin elevation, sick, proteinuria, oral ulcer, loss of appetite, and transaminase elevation. The most AEs were in grade I~II. Conclusion The combination therapy of apatinib plus S-1 was effective and well tolerated in the treatment of advanced ESCC patients after first-line chemotherapy failure. The combination therapy has the potential to be a potent therapeutic option for advanced ESCC patients after first-line chemotherapy failure. [ABSTRACT FROM AUTHOR]

[Display omitted] • A comprehensive analysis was conducted on the formation process of ridges from multiple perspectives. • Data processing was carried out using Python programming methods. • The shape function expression was obtained by fitting the contour data points of the ridge cross-section. • The intensity of soil disturbance was analyzed using regional statistical methods. • Technical support is provided for analysis of ridge forming. The Northwest of China is a typical production mode of rain-fed agriculture, which mostly adopts the whole film-mulching and double ridge–furrow technique to address the difficulty of surface water storage. However, the quality of ridge formation directly affects the water storage on both sides of the ridges, the reliability of plastic film mulching, and the crop growth. This study focused on the process of rotary tillage ridging, took different inclination angles and depths of ridger as variable factors, explored the influence of different operation parameters on the quality of ridge forming. The soil viscoelastic model was established in the study using the discrete element method. The changes in ridger resistance, ridge structure, and soil particle disturbance were analyzed in detailed, respectively. The results indicated that as the inclination angles and depths of ridger increased, the resistance of ridger also increased. The height of the ridges significantly influenced by the inclination angles and depths of ridger, and under the same inclination angles of ridger, the height of the ridges was directly proportional to the depth of ridger. Under different combinations of operational parameters, the height of the small ridges had good agreement with the ridging agronomy. As for the large ridges, when the depth of ridger was 100 mm and the inclination angles were 15°, 30°, and 45°, the working parameters met the agronomic requirements for ridge forming. In terms of soil disturbance, the soil located within a range of 30–90 mm from the surface was most susceptible to disturbance from the rotary tillage and the ridger, and the soil disturbance was stronger in the small ridges compared to the large ridges. The results of study contributed to a deeper understanding of the rotary tillage ridging process and provided insights into the factors influencing the quality of ridge forming. [ABSTRACT FROM AUTHOR]

Black scraper, Thamnaconus modestus is a filefish with high market value but the standing stock has been decreased in the past years due to the overexploiting and environmental fluctuations. Industrial culture of black scraper relieved the tense between supply and demand but at the same time brought some disease problems. In this study, we reported a mass death case of cultured Thamnaconus modestus caused by Amyloodinium ocellatum in China. The disease outbroke at temperature of 22–24 °C and the main clinical symptoms were anoxia, decreased feeding activity, reduced mobility, lost balance and subcutaneous hemorrhage. According to the observation, the trophonts of A. ocellatum were non-transparent, suborbicula and the main parasitized tissues were gill and fin, accompanying with the necrocytosis of gill lamella, and hyperplasia of fin cell. The amplification and sequencing of the ribosomal RNA gene showed the parasite was 97.41–99.92% similar with A. ocellatum. The case that amyloodiniosis only occurred in T. modestu but not in turbot cultured with the same condition, indicated the tolerance of former was lower than the latter and farmers should take more surveillance to avoid the mass fish mortality in temperate season. This is the first report about the occurrence of amyloodiniosis in the black scraper. • This is the first report about the occurrence of Amyloodinium ocellatum in the black scraper. • The report would be a good reminder for avoiding mass death during culturing of black scraper. [ABSTRACT FROM AUTHOR]

Abstract: As one of the largest energy consumer in the world, China has been facing great pressure to guarantee energy supply security. Investigating the driving forces dominating China energy consumption levels and their evolution may help to institute energy saving policy. Nowadays, the LMDI (logarithmic mean Divisia index) method has become a popular tool to find the nature of the factors that influence the changes in energy consumption. But the LMDI method does not study such factors as fixed asset investment and labor. Combined C-D production function and LMDI method, a new LMDI method is generalized, and that method can be utilized to study many factors. Finally, the new generalized LMDI method is utilized to analyze the driving factors dominating China's energy consumption over the period 1991–2011. Since 1992, China has become a net energy importer. Energy intensity effect played the dominant role in decreasing energy consumption during the study period. However, the investment effect and labor effect were the critical factors in the growth of energy consumption. [Copyright &y& Elsevier]