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In this study, an Al-Y coating was applied to enhance the property of oxidation resistance on the surface of γ- TiAl alloys by rf magnetron sputtering. The isothermal oxidation tests were investigated at 900 °C for 100 h. The coating characteristics and microstructure of coating after isothermal oxidation were inspected by XRD and SEM methods respectively, and coating bonding strength was investigated by scratch tester. Results show that Al2O3 and Y2O3 were produced on the surface of γ-TiAl alloys to enhance oxidation resistance during the isothermal oxidation test. Diffusion layer with rich element of Al provides abundant Al to surface for formation of a continuous Al2O3 layer which increases oxidation resistance effectively. Oxides of YAlO3 and YAG were formed during the oxidation tests, which were beneficial for the strength, hardness and fracture toughness of crystal grain of Al2O3. Furthermore, Element of Ti diffused into surface from substrate was restrained by Al because of the formation of TiAl3 and TiAl, which avoid the layer-broken by titanium oxides with porous structure Keywords: Oxidation behavior; Magnetron sputtering; High temperature; Al-Y coating; γ-TiAl alloy; Diffusion

Water resources allocated to the agricultural sector in the Yellow River basin are being reduced due to severe water scarcity and an increasing demand by the non-agricultural sectors, which imply surface irrigation modernization and the adopting water-saving technologies. The Hetao irrigation district has 0,570 Mha of irrigated land; traditional basin irrigation is the most common irrigation method. Its general conditions are adequate for surface irrigation due to the high charge of sediments on irrigation water and, among other factors, due to its appropriateness to leach salts. The new technologies of surface irrigation, including the modernized furrowed and flat basin irrigation systems, require the adoption of effective precise land leveling to reach the best performance standards. In this context, the development of high quality land leveling operation is a main condition for irrigation modernization. The laser land leveling technology provides for high land leveling quality, with significant benefits on water saving, salinity control and crop productivity. The irrigation modernization also requires adopting adequate irrigation scheduling, control of inflow discharges and of related application times. The DSS methodology may contribute to improved design and management. The DSS SADREG aims to support design and selection of farm surface irrigation alternatives; it ranks those alternatives relative to irrigation performance and environmental and economic impacts using Multicriteria analysis. The DSS application bases on three years field work to evaluate the traditional practices and for the parameterization of design models from field irrigation systems evaluation. This paper presents the following SADREG application results: (i) evaluation of land leveling operation based on field observations and the comparison between laser and common practices; (ii) land parcels description, namely its size, slopes and water supply conditions; (iii) SADREG base models parameterization, including crop irrigation scheduling, infiltration, SIRMOD hydraulic simulation and economics; and (iv) presentation and comparison of alternatives of field irrigation modernization.

Hetao irrigation district (Hetao) is located in the upper reaches of Yellow River basin. Surface irrigation is used because there is a high charge of sediments in the irrigation water and is appropriate to leach salts. Basin irrigation is the most used irrigation method. Traditional practices are inadequate for saving water and surface irrigation modernization is needed. A better knowledge of the performance of irrigation systems is required to base that modernization. An experimental research work was developed at Dengkou Experimental Station to assess the irrigation performance in laser land leveled fields. It is located on an irrigation sector supplied in agreement with a rotational delivery scheme managed by the Water Users Association (WUA), which usually practices a total of 7 events and the autumn irrigation. The typical field length is 50 m, with a width between 10 and 50 m, with a silt loamy soil. The irrigation performance was assess from field measurements carried out in several fields, cropped with the main irrigated crops, wheat, maize and sunflower. The irrigation field evaluation was based on observations of advance and recession times, soil moisture, inflow discharges, application time, topographic survey and crop development data. In addition, infiltration curves for typical and seasonal irrigation events were developed, and the Kostiakov infiltration parameters were estimated from field observations using the inverse method with the SIRMOD model. The irrigation operative parameters and the performance indicators were obtained, concluding that the distribution uniformity is very high, between 90 and 96%, and that the cutoff time has a very sensitive effect on beneficial water use fraction. Finally, the results of this study allowed the appropriate knowledge, including the crop irrigation scheduling data, for the irrigation design models aimed at developing irrigation alternatives.

Background: Airway inflammation and inflammatory mediators play an imperative role in the pathogenesis of COPD. Currently, understanding of the anti-inflammatory effect of Chinese herbal medicine (CHM) on COPD is limited, and CHM’s mechanism of actions is unclear. This systematic review (SR) evaluates anti-inflammatory effects of CHM on the concentration of various inflammatory mediators, such as Tumor Necrosis Factor-alpha (TNF-α) and interleukin-8 (IL-8), in the sputum and serum of COPD patients. Methods: The studies chosen for this SR were obtained from Chinese and English databases. The study selection criteria were based on randomized, controlled trials of stable COPD patients on adjunct oral CHM; and the changes in concentration of inflammatory mediators post-treatment were analyzed via meta-analysis. Results: 2,268 patients in 29 studies were evaluated. 2 studies were assessed to be of low-risk in all domains. The results showed significant reduction in the serum level of IL-8 (mean: -1.27 and 95% confidence interval (CI) [-1.86, -0.68]) and TNF-α (Mean: -0.72 and 95% CI [-1.01, -0.43]) in patients treated with CHM plus bronchodilators, compared to bronchodilators alone. Conclusion: This SR explains CHM’s mechanism of action, and demonstrates CHM’s anti-inflammatory effects on patients with stable COPD.

BACKGROUND It has been found that the -2518 C-C motif ligand (CCL)-2 promoter variant increases the risk of developing active tuberculosis (TB). OBJECTIVE To study the association between -2518 variants and susceptibility to TB. DESIGN We searched Medline, PubMed and the Wan Fang databases for human genetic studies on whether the -2518 CCL2 polymorphism influences the expression of active TB. Articles published from January 1998 to November 2010 were included. A random effects model was conducted in the meta-analysis. RESULTS The CCL2-2518G allele (OR 1.51, 95%CI 1.11-2.04, P = 0.008) showed significant association with susceptibility to TB. In genotype analysis, the recessive model (CCL2 genotype GG, OR 1.66, 95%CI 1.19-2.33, P = 0.003) was slightly superior to the dominant model (G carrier genotypes OR 1.53, 95%CI 1.07-2.17, P = 0.018). These observations were prominent among Asians and Latin-Americans of Hispanic ancestry, but not in Africans from Ghana and South Africa. The presence of epistatic genes in one population but not in the other, environmental differences and pathogen virulence may account for this. CONCLUSION The CCL2-2518G allele increases the risk of developing TB in Asians and Hispanics.

This paper discusses the path-following performance of actively-steered articulated vehicles based on measurement signals from two ‘ground-watching’ navigation systems (GWNS). The ground-watching navigation systems are described. These use high-speed USB-3 cameras and an image processing computer to measure and calculate off-tracking distance for a path-following steering controller. Full-scale field tests are performed using an experimental articulated vehicle, tested under both open-loop and closed-loop conditions. Off-tracking distance at the rear camera with respect to the front camera is controlled to be less than 0.1m for tests with both GWNSs.

There is substantial data that suggests an abnormality of innate immunity in patients with primary biliary cholangitis (PBC) which includes the transcription factor nuclear factor-kB (NF-kB) and well as downstream inflammatory signaling pathways. In addition, Immuno-Chip analysis has identified a novel PBC-associated locus near the receptor activator of NF-kB ligand (RANKL) gene. Based on these observations, we investigated the role of the RANKL axis in the liver of patients with PBC compared to controls. We used immunohistochemistry to quantitate liver expression of RANKL, its receptor (RANK), and importantly the decoy receptor osteoprotegerin (OPG), including a total of 122 liver samples (PBC = 37, primary sclerosing cholangitis = 20, autoimmune hepatitis = 26, chronic hepatitis B = 32 and unaffected controls = 7). In addition, we studied RANKL-RANK-OPG co-localization in CD4 and CD8 T cells, B cells, dendritic cells, macrophages, NK, NKT cells, hepatocytes, and cholangiocytes. We report herein that RANK is constitutively expressed by cholangiocytes in both unaffected and diseased liver. However, cholangiocytes from PBC express significantly higher levers of RANK than either the unaffected controls or liver diseased controls. CD4, CD8 and CD19 cells with in the portal areas around bile ducts in PBC express significantly higher levels of RANKL compared to controls. Importantly, the overall hepatic RANKL level and the ratio of hepatic RANKL/OPG correlated with disease severity in PBC. In conclusion, our data indicate a role of RANK-RANKL axis in the innate immune activation in PBC and we hypothesize that the damaged cholangiocytes, which express high levels of RANK, lead to the recruitment of RANKL positive cells and ultimately the classic portal tract infiltrates.