75 research outputs found
Influence of fiber hollowness on the local thermo-electro-elastic field in a thermoelectric composite
The fiber geometry is one of the important parameters in the effective conversion performance and local strength of thermoelectric composites. In this study, the plane problem of a hollow fiber embedded within a non-linear thermoelectric medium in the presence of a uniform remote in-plane electric current and a uniform remote energy flux is investigated based on the complex variable method. Closed-form expressions for all the potential functions characterizing the thermoelectric field and the associated thermal stress field in both the matrix and fiber are obtained by solving the corresponding boundary value problem. Numerical examples are presented to illustrate the effect of hollowness ratio of the fiber on the local energy conversion efficiency and interfacial thermal stress concentration. It is found that a higher conversion efficiency and a lower amount of thermal stress concentration around a hollow fiber than that around a solid fiber could be achieved simultaneously by appropriate selection of the hollowness ratio of the fiber. The results can be directly used for performance optimization and reliability evaluation in design of thermoelectric composites in engineering
Study on multi-axis sine vibration test control techniques
This paper describes several key aspects about multi-axis sine vibration test control techniques including the identification of the system frequency response function, synchronization of the input and output signals, the generation of the sinewave, the control algorithm, etc. A multi-axis sine vibration controller is developed based on these key techniques and the major framework of the controller is introduced. Finally, a dual axial experiment is carried out by the controller. The test results show the feasibility of the control algorithm and the good control strategy of the multi-axis sine vibration controller in which the key techniques are realized
Ti4O7/g-C3N4 for Visible Light Photocatalytic Oxidation of Hypophosphite: Effect of Mass Ratio of Ti4O7/g-C3N4
Hypophosphite wastewater treatment is still a critical issue in metallurgical processes and the oxidation of hypophosphite to phosphate followed by the precipitation of phosphate is an important strategy for hypophosphite wastewater treatment. Herein, Ti4O7/g-C3N4 photocatalysts with various mass ratios (Ti4O7 (m): g-C3N4 (m) = 0.5, 0.2, 0.1, and 0.05) were synthesized by a hydrolysis method and the effect of the mass ratio of Ti4O7 (m): g-C3N4 (m) on Ti4O7/g-C3N4 visible light photocatalytic oxidation of hypophosphite was evaluated. The as-prepared Ti4O7/g-C3N4 were characterized and confirmed by SEM, XPS, XRD and FTIR. Moreover, the specific surface area and the distribution of pore size of Ti4O7/g-C3N4 was also analyzed. Our results showed that Ti4O7/g-C3N4 exhibited remarkably improved photocatalytic performance on hypophosphite oxidation compared with g-C3N4 and meanwhile 1:2-Ti4O7/g-C3N4 with a mass ratio of 0.5 showed the best photocatalytic performance with the highest oxidation rate constant (17.7-fold and 91.0-fold higher than that of pure g-C3N4 and Ti4O7, respectively). The enhanced performance of photocatalytic oxidation of hypophosphite was ascribed to the heterojunction structure of Ti4O7/g-C3N4 with broader light absorption and significantly enhanced efficiency of the charge carrier (eā-h+) generation and separation. Additionally, the generated Ā·OH and Ā·O2- radicals contributed to the hypophosphite oxidation during the photocatalytic system
MicroRNA miR-326 regulates TH-17 differentiation and is associated with the pathogenesis of multiple sclerosis
MicroRNA miR-326 regulates TH-17 differentiation and is associated with the pathogenesis of
multiple sclerosis
Changsheng Du1,5, Chang Liu1,5, Jiuhong Kang1,2, Guixian Zhao3, Zhiqiang Ye4, Shichao Huang1, Zhenxin Li3, Zhiying Wu3 & Gang Pei1,2
Interleukin 17 (IL-17)-producing T helper cells (TH-17 cells) are increasingly recognized as key participants in various autoimmune diseases, including multiple sclerosis. Although sets of transcription factors and cytokines are known to regulate TH-17 differentiation, the role of noncoding RNA is poorly understood. Here we identify a TH-17 cellāassociated microRNA,
miR-326, whose expression was highly correlated with disease severity in patients with multiple sclerosis and mice with experimental autoimmune encephalomyelitis (EAE). In vivo silencing of miR-326 resulted in fewer TH-17 cells and mild EAE, and its overexpression led to more TH-17 cells and severe EAE. We also found that miR-326 promoted TH-17 differentiation by targeting Ets-1, a negative regulator of TH-17 differentiation. Our data show a critical role for microRNA in TH-17 differentiation and the pathogenesis of multiple sclerosis
Progress of Pharmaceutical Continuous Crystallization
Crystallization is an important unit operation in the pharmaceutical industry. At present, most pharmaceutical crystallization processes are performed in batches. However, due to product variability from batch to batch and to the low productivity of batch crystallization, continuous crystallization is gaining increasing attention. In the past few years, progress has been made to allow the products of continuous crystallization to meet different requirements. This review summarizes the progress in pharmaceutical continuous crystallization from a product engineering perspective. The advantages and disadvantages of different types of continuous crystallization are compared, with the main difference between the two main types of crystallizers being their difference in residence time distribution. Approaches that use continuous crystallization to meet different quality requirements are summarized. Continuous crystallization has advantages in terms of size and morphology control. However, it also has the problem of a process yield that may be lower than that of a batch process, especially in the production of chirality crystals. Finally, different control strategies are compared
Postoperative C-reactive protein/albumin ratio as a novel predictor for short-term complications following gastrectomy of gastric cancer
Abstract Background Postoperative complications following gastric cancer resection remain a clinical problem. Early detection of postoperative complications is needed before critical illness develops. The purpose of this study was to evaluate the prognostic value of C-reactive protein/albumin ratio in patients with gastric cancer. Methods A total of 322 patients undergoing curative (R0) gastrectomy between 2015 and 2017 were retrospectively analyzed. Univariate and multivariate analyses were performed to identify clinical factors predicting postoperative complications. The cutoff values and diagnostic accuracy of C-reactive protein/albumin ratio and C-reactive protein were determined by receiver-operating characteristic curves. Results Among all of the patients, 85 (26.4%) developed postoperative complications. The optimal cutoff of C-reactive protein/albumin ratio was set at 3.04 based on the ROC analysis. Multivariate analysis identified C-reactive protein/albumin ratio was an independent risk factors for complications after gastrectomy (OR 3.037; 95% CI 1.248ā7.392; PĀ =Ā 0.014). Additionally, C-reactive protein/albumin ratio showed a higher diagnostic accuracy than C-reactive protein on postoperative day 3 (AUC: 0.685 vs 0.660; sensitivity: 0.624 vs 0.471; specificity: 0.722 vs 0.835). Conclusions Elevated C-reactive protein/albumin ratio was an independent predictor for postoperative complications following gastrectomy of gastric cancer, and the diagnostic accuracy was higher than C-reactive protein alone. Overall, postoperative C-reactive protein/albumin ratio may help to identify patients with high probability of postoperative complications
Adaptation Strategy Can Ensure Seed and Food Production With Improving Water and Nitrogen Use Efficiency Under Climate Change
Abstract Adaptation strategies can reduce the negative impacts of climate change on food security. As an important part of food security, more attention should be paid to seed security, as it determines the crop planting area and ultimately affects food production, especially in major seed production locations, such as the Hexi Corridor in China. This region is an important production base of grain (including field maize and wheat) and maize seed, but the shortage of water resources and low use efficiency of water and nitrogen (N) seriously constrain the sustainable development of agriculture. Formulating an adaptation strategy to balance the seed and food production and resource use efficiency is an important way to maintain regional as well as national food production. We established an optimizationāsimulation framework, which consists of a novel crop production function and a gridābased crop model, APSIM. This framework was used to optimize agricultural management and evaluate its performance considering the spatioātemporal variability of climate and soil properties, actual crop water consumption and N uptake during each growth stage, and interactive sensitivity coefficients of water and N at different growth stages under climate change. We show that the proposed adaptation strategy could save 0.31Ā kmĀ³ of irrigation water and 22 thousand tonnes of N fertilizer, and increase seed and food production by 33 thousand tonnes, compared with traditional practices. Significant increases in irrigation water productivity and N use efficiency can be expected by using the adaptation supporting the sustainable development of agriculture
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