76 research outputs found
Robust Adaptive Fuzzy Control of Chaos in the Permanent Magnet Synchronous Motor
An adaptive fuzzy control method is developed to control chaos in the permanent magnet synchronous motor drive system via backstepping. Fuzzy logic systems are used to approximate unknown nonlinearities, and an adaptive backstepping technique
is employed to construct controllers. The proposed controller can suppress the chaos of PMSM and track the reference signal successfully. The simulation results illustrate its effectiveness
Marginal resection for osteosarcoma with effective neoadjuvant chemotherapy: long-term outcomes
The Economic Impact of Linking the Pilot Carbon Markets between Hubei and Guangdong Provinces: A Bottom-up CGE Analysis
Controlling greenhouse gas emission is an important task for China to actively address global climate change. In order to achieve the 2015 target of 17% reduction in carbon intensity against 2010 levels, China has adopted a series of market-based policy measures. This paper utilizes SICGE-R-CO2 (The multiregional General Equilibrium model with carbon dioxide emission rights trading module developed by State Information Center) to simulate the mitigation costs and economic influences of Guangdong’s and Hubei’s independent mitigation efforts and linking cross-provincial carbon trading. It is found out that linking carbon trading market can effectively reduce the mitigation cost of the whole region. Carbon price of Guangdong and Hubei stands at 102.9 RMB/tonne of carbon dioxidene of carbon dioxide and 14.8 RMB/tonne of carbon dioxide and the average emissions reduction cost for the region is 972.4 RMB/tonne of carbon dioxide, if the two provinces take actions independently. However, in a linking carbon market where Guangdong buys from Hubei 23 million tons emission permits (824 million RMB), average carbon price will drop to 35.9 RMB/tonne of carbon dioxide and emissions reduction cost 567.9 RMB/tonne of carbon dioxide. From the perspective of industries, output reduction of high emitters is the main drive for emission reduction, while substitution effect between different fuels is limited. In terms of macro economy, carbon tax and carbon market will exert negative impact on economic growth, especially on investment, and consequent price growth is not large. Although the GDP of Hubei (seller of emission right) suffers larger loss, its welfare will be improved. From the perspective of sectors, industries with high emissions like power, non-metallic mineral products, non-metallic mining and dressing, metal smelting and rolling and chemical industries are heavily affected, but service industry is much more immune. In the last part of the paper, major conclusions are drawn and policy proposals are offered
Prefabrication of two-dimensional Ni–W/TiN films on oil-gas X52 steels by pulse electrodeposition
The main aim of this investigation was to prefabricate two-dimensional Ni–W/TiN films on oil-gas X52 steel substrates via pulse electrodeposition (PE). The influences of the TiN content in the bath on the surface morphology, nano-hardness, wear, and corrosion properties of the films were also discussed. The results indicated that the TiN particle size was only ∼33 nm in 8 g/L TiN electrolyte, which was ∼2.4 times less than that of TiN in 16 g/L solution. The Ni–W/8TiN film exhibited a uniform, smooth surface, and the depression depth and protrusion height were 45.3 nm and 81.7 nm, respectively. Three diffraction peaks at 43.72, 50.78, and 75.26° in the Ni–W/4TiN film emerged as the sharpest and narrowest peaks among the four films. Three XPS peaks for the Ni 2p3/2 were present at 852.13, 856.35, and 861.87 eV in the Ni–W/8TiN film, corresponding to Ni, Ni2+ (Ni(OH)2), Ni3+ (NiOOH) species. Besides, the XPS peak of W 4f7/2, which located at 33.85 eV belonged to elemental W. The Ni–W/8TiN film had the lowest wear depth and width at 32.1 μm and 5.7 mm, respectively. Only some narrow and shallow scratches were found on the Ni–W/8TiN film surface, showing its outstanding tribological properties among the films tested. In addition, the Ni–W/4TiN film showed the highest mean frictional coefficient of 0.73, which was ∼1.6 times more than that of the Ni–W/8TiN film.The research is supported by the National Natural Science Foundation of China (Granted no. 51974089)
Numerical Studies on the Failure Process of Heterogeneous Brittle Rocks or Rock-Like Materials under Uniaxial Compression
In rocks or rock-like materials, the constituents, e.g. quartz, calcite and biotite, as well as the microdefects have considerably different mechanical properties that make such materials heterogeneous at different degrees. The failure of materials subjected to external loads is a cracking process accompanied with stress redistribution due to material heterogeneity. However, the latter cannot be observed from the experiments in laboratory directly. In this study, the cracking and stress features during uniaxial compression process are numerically studied based on a presented approach. A plastic strain dependent strength model is implemented into the continuous numerical tool—Fast Lagrangian Analysis of Continua in three Dimensions (FLAC3D), and the Gaussian statistical function is adopted to depict the heterogeneity of mechanical parameters including elastic modulus, friction angle, cohesion and tensile strength. The mean parameter μ and the coefficient of variance (hcv, the ratio of mean parameter to standard deviation) in the function are used to define the mean value and heterogeneity degree of the parameters, respectively. The results show that this numerical approach can perfectly capture the general features of brittle materials including fracturing process, AE events as well as stress-strain curves. Furthermore, the local stress disturbance is analyzed and the crack initiation stress threshold is identified based on the AE events process and stress-strain curves. It is shown that the stress concentration always appears in the undamaged elements near the boundary of damaged sites. The peak stress and crack initiation stress are both heterogeneity dependent, i.e., a linear relation exists between the two stress thresholds and hcv. The range of hcv is suggested as 0.12 to 0.21 for most rocks. The stress concentration degree is represented by a stress concentration factor and found also heterogeneity dominant. Finally, it is found that there exists a consistent tendency between the local stress difference and the AE events process
Osteosarcoma of the distal radius treated by en bloc resection and reconstruction with a fibular shaft preserving the radiocarpal joint: A case report
Photograph of the Travertine Creek and waterfall in the Chickasaw National Recreation Area
Splenectomy for treating hepatosplenic candidiasis: Two cases and literature review suggesting its feasibility
Background: Hepatosplenic candidiasis is a rare but severe complication in immunocompromised patients undergoing chemotherapy. Antifungal agents are widely accepted as the first choices for therapy. However, resistance to or side-effect of antifungal agents may comxpromise its efficiency. Splenectomy has also been rarely performed as treatment for this disease. Methods: We present two cases of splenectomy for treating hepatosplenic candidiasis after failure of the initial drug therapy. Literatures on splenectomy as treatment for hepatosplenic candidiasis were searched in Pubmed and summarized. Results: Two leukemia patients developed hepatosplenic candidiasis after received chemotherapy for their primary diseases. Various antifungal agents including amphotericin B were all demonstrated failure to cure fever and the Candida abscesses due to resistance or intractable side-effect. Laparoscopic splenectomy were finally performed and resolved the candidiasis successfully. A total of 12 splenectomy cases for treating hepatosplenic candidiasis had been previously reported in literature. All the cases showed either resistance or unimproved to initial antifungal therapies. Splenectomy provided salvage therapeutic value in all cases. Conclusion: Splenectomy has therapeutic effect and may change the traditional concept in most surgeons. The present study may expand an alternative strategy in clinical practice guideline for the management of hepatosplenic candidiasis
Casein Hydrolysate Alleviates Adipose Chronic Inflammation in High Fat-Diet Induced Obese C57BL/6J Mice through MAPK Pathway
Obesity-induced adipose chronic inflammation is closely related to the development of insulin resistance and T2DM. Tripeptides l-valyl-l-prolyl-l-proline (VPP) and l-isoleucyl-l-prolyl-L-proline (IPP) derived from bovine casein have been reported to prevent inflammatory changes and mitigate insulin resistance in adipocytes. In this study, we aimed to investigate the influence of casein hydrolysates (CH) containing VPP and IPP on a high fat diet (HFD)-induced obese mice and cytokine TNF-α-induced adipocytes. Our data showed that CH alleviated chronic inflammation both in vivo and in vitro. 4% CH suppressed HFD-induced systemic inflammatory factors, hypertrophic white adipocytes, and macrophage infiltration. More importantly, CH was able to improve adipocyte dysfunction induced by TNF-α by increasing the expression of CCAAT/enhancer binding protein α (C/EBP-α) rather than peroxisome proliferator-activated receptor γ (PPAR-γ). Furthermore, CH also dose-dependently suppressed mitogen-activated protein kinase (MAPK)-c-Jun N-terminal kinase (JNK) phosphorylation and enhanced the phosphorylation of Erk 1/2, but not nuclear factor-kappa B (NF-κB) p65 phosphorylation, in TNF-α-induced 3T3-L1 cells. These results indicated that CH could ameliorate adipose chronic inflammation through the MAPK pathway. Altogether, our findings suggested that 4% CH supplementation for 6 weeks exerted a protective role in preventing obesity-related inflammation and adipose dysfunction
De novo cancers following liver transplantation: a single center experience in China.
BACKGROUND: De novo cancers are a growing problem that has become one of the leading causes of late mortality after liver transplantation. The incidences and risk factors varied among literatures and fewer concerned the Eastern population. AIMS: The aim of this study was to examine the incidence and clinical features of de novo cancers after liver transplantation in a single Chinese center. METHODS: 569 patients who received liver transplantation and survived for more than 3 months in a single Chinese center were retrospectively reviewed. RESULTS: A total of 18 de novo cancers were diagnosed in 17 recipients (13 male and 4 female) after a mean of 41 ± 26 months, with an overall incidence of 3.2%, which was lower than that in Western people. Of these, 8 (3.32%) cases were from 241 recipients with malignant liver diseases before transplant, while 10 (3.05%) cases were from 328 recipients with benign diseases. The incidence rates were comparable, p = 0.86. Furthermore, 2 cases developed in 1 year, 5 cases in 3 years and 11 cases over 3 years. The most frequent cancers developed after liver transplantation were similar to those in the general Chinese population but had much higher incidence rates. CONCLUSIONS: Liver transplant recipients were at increased risk for developing de novo cancers. The incidence rates and pattern of de novo cancers in Chinese population are different from Western people due to racial and social factors. Pre-transplant malignant condition had no relationship to de novo cancer. Exact risk factors need further studies
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