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In view of the poor corrosion resistance of 7075 aluminum alloy in marine environment， the microstructure and corrosion resistance of composite oxide coating on the surface of 7075 aluminum alloy obtained by combining magnetron sputtering and micro arc oxidation technologies were investigated. Firstly， the aluminum alloy surface was pre-coated with titanium film by magnetron sputtering technology， and then a composite oxide coating was prepared by micro-arc oxidation technology. The microstructure and phase composition of the composite oxide coating were analyzed by SEM， EDS and XRD. The corrosion resistance of such coating in 3.5% NaCl solution was studied by electrochemical workstation. Results showed that compared with the oxide coating obtained by a direct micro arc oxidation of aluminum alloy， the composite oxide coating formed on the Ti-coated aluminum alloy by micro arc oxidation had lower porosity and higher thickness， presenting better corrosion resistant performance.

Oxide superconductor is one of the most important forms of unconventional superconductors, in which the transition temperatures of thallium series, mercury series and copper-carbon series superconductors can reach 110 K or above. High superconducting transition temperature and irreversible magnetic field in liquid nitrogen temperature region have attracted much attention. Obviously, the high superconducting critical temperature increases the choice of cooling medium for superconducting applications. Economical and practical coolants are expected to expand the application fields of these high superconducting transition temperature (Tc) superconductors and increase the feasibility of long-term operation. In this paper, the development and superconducting properties of 110 K superconducting materials including thallium, mercury and copper-carbon superconductors are introduced and summarized, and the factors affecting the superconducting transition temperature are analyzed theoretically to qualitatively explain the reasons for the high Tc of high temperature superconductors. Special attention is paid to the analysis of the differences of their irreversible fields, and the possible new applications of these high critical temperature superconductors are prospected. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of soil water stress on morphology and physiological characteristics of soybean, three different drought - resistant soybean varieties ( Hefeng25, Heinong44 and Jindou21 ) were selected for pot experiment. Moderate and severe soil water stress were applied from beginning of pod formation to seed filling stage. Morphological characteristics, chlorophyll content, photosynthetic rate, SOD activity, POD activity, CAT activity were examined. The results of drought resistance of tested cuhivars were shown as : Jindou21 > Heinong44 > Hefeng25. Jindoti21 of the most resistant rootstocks demonstrated the powerful growth advantage under soil water stress. Many indices of Jindou21 were higher than Heinong44 and Hefeng25, including plant height, pods number per plant, grain number per plant, grain weight per plant, chlorophyll content, Pn ( photosynthetic rate) and POD activity. But GS (stomatal conductance) and Tr (transpiration rate) of Jindou21 were higher than Heinong44 and Hefeng25, their decrease were significantly higher than Heinong44 and Hefeng25 under severe soil water stress. Jindou21 had higher water use efficiency. These morphological characteristics and physiological index could be used to evaluate drought resistance of soybean. [ABSTRACT FROM AUTHOR]

Objective To study the seroprevalence of Lyme disease and scrub typhus among college freshmen in Yunnan province. Methods ELISA method was used to detect IgG antibody to Lyme disease and scrub typhus, and the antibody positive rate was calculated. Results Totally 42 college freshmen were enrolled in this study. The positive rates of IgG antibody to Lyme disease and scrub typhus were 2.4% and 4.8%,respectively. Conclusion There are Lyme disease and scrub typhus infections in Yunnan province. The surveillance,prevention and control for these insect-borne infectious diseases should be strengthened. [ABSTRACT FROM AUTHOR]

Fuzzy reasoning Petri nets (FRPNs) can model the uncertain quality abnormity diagnosis of manufacturing process effectively. But it is hard to simulate the model because of its complex graphical notation and logic structure of fuzzy reasoning. A mapping relation between the fuzzy reasoning rules and elements of Stateflow was designed, so the FRPNs model was converted into Stateflow model that can be simulated conveniently. The Stateflow model took quality abnormal pattern data of control chart as input, and showed the uncertain quality abnormity diagnosis process dynamically. Taking uncertain quality abnormity diagnosis of some workpiece as an example, the application process of proposed approach was introduced in detail. The experimental results show that this model can output the contribution degree of assignable causes to current control chart abnormity, and offers decision support for eliminating the abnormity. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between paternal exposure to occupational electromagnetic radiation and the sex ratio of the offspring., Methods: We searched various databases, including PubMed, Embase, Cochrane Library, OVID, Bioscience Information Service (BIOSIS), China National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals and Wanfang Database, for the literature relevant to the association of paternal exposure to occupational electromagnetic radiation with the sex ratio of the offspring. We conducted a meta-analysis on their correlation using Stata 11.0., Results: There was no statistically significant difference in the sex ratio between the offspring with paternal exposure to occupational electromagnetic radiation and those without (pooled OR = 1.00 [95% CI: 0.95 -1.05], P = 0.875). Subgroup analysis of both case-control and cohort studies revealed no significant difference (pooled OR = 1.03 [95% CI: 0.99 -1.08], P = 0.104 and pooled OR = 0.98 [95% CI: 0.99 -1.08], P = 0.186, respectively)., Conclusion: Paternal exposure to occupational electromagnetic radiation is not correlated with the sex ratio of the offspring.

Objective: To identify the genotype and clades of hantavirus (HV) in Zhejiang province., Methods: The partial S and M segment of the HV in Zhejiang province were amplified with RT-PCR using genotype-specific primers, and then were sequenced and compared with other known hantaviruses., Results: The genotype of 11 strains were HTNV and other 7 strains were SEOV by homology and phylogenesis analysis, yet the clade distribution was significantly different among foci of Zhejiang with 5 clades of HTNV and 3 clades of SEOV. There also existed special clade of HTNV named ZNB-1, ZNB-2, A3 and of SEOV named Gou3, ZJ5. The homology of M segments of ZNB-1 and ZNB-2 with other HTNV clades were 69.7%-74.0% except Nc167, A3 with other HTNV clades were 73.6%-76.3% except B78., Conclusion: Zhejiang province is co-circulating with HTN and SEO. Say the least of the clades are 5 of HTNV and 3 of SEOV and there also existed special clade of HTNV and SEOV.

Objective: To study the curative effects of pirfenidone (PF) on pulmonary fibrosis induced by paraquat (PQ) in mice and to provide the theoretical basis for clinical treatment., Methods: Ninety adult healthy male ICR mice were randomly divided into six groups: control group, PQ group, 2 mg/kg Dexamethasone group, 25 mg/kg PF group, 50 mg/kg PF group and 100 mg/kg PF group, there were 15 mice in each group. The corresponding volume of normal saline was given to the each mouse in control group according to the weight, after 2 h 0.1% CMC was given to the each mouse of control group one time by intragastric administration, then the CMC was administrated at regular time until sacrifice. All mice for other 5 groups were exposed to 100 mg/kg PQ by intragastric administration. At 2 h after exposure to PQ, 0.02 ml/10 g dexamethasone and 25, 50, 100 mg/kg PF were given to mice for dexamethasone group and for 3 PF groups by intragastric administration each day for 49 days, respectively. The lung coefficient was calculated and pathological changes of lung tissue were observed by HE staining for each mouse. The hydroxyproline (HYP) level in lung tissue was measured for each mouse. The mRNA level of and the protein level of TGF-β(1) in lung tissue for each mouse were determined, and the protein level of TGF-β(1) in the bronchus-alveolus lavage fluid (BALF) of each mouse was detected., Results: The survival rates on the 3rd day in PQ group, 3 PF groups and dexamethasone group were 53.33%, 46.67%, 73.33%, 86.67% and 80%, respectively. The survival rates on the 3rd day in dexamethasone group, 50 mg/kg and 100 mg/kg PF groups were significantly higher than those of PQ group and 25 mg/kg PF group (P < 0.05). The lung coefficients of 3 PF groups were significantly lower than that of the PQ group (P < 0.05). The lung tissue HYP levels of dexamethasone group and 3 PF groups were 50.95 ± 11.65, 44.52 ± 9.48, 43.27 ± 6.01 and 40.82 ± 5.90 mg/g respectively, which were significantly lower than that (74.27 ± 3.68) of PQ group (P < 0.01). The TGF-β(1) protein levels of BALF in dexamethasone group, 50 and 100 mg/kg PF groups were 22.03 ± 7.27, 27.75 ± 5.84 and 21.31 ± 6.82 ng/ml respectively, which were significantly lower than that (52.52 ± 15.51) ng/ml of PQ group (P < 0.01) The expression level of TGF-β(1) mRNA in 100 mg/kg PF group decreased significantly, as compared with PQ group (P < 0.01)., Conclusion: PF could reduce the collagen deposition and pulmonary fibrosis induced by PQ in mice lungs.

Objective: To investigate the transmitting phlebotomine sandfly in Minfeng County, a newly-identified endemic area of visceral leishmaniasis in the south of Talim Pendi of Xinjiang., Methods: Sandflies were collected using routine methods in and around the Yatonggusi village of Andier Township. The sandflies were identified to get their composition. Sandfly density was calculated following an observation at a given spot and time-period, and their appearance was recorded at night-time and day-time. Sandflies were dissected to analyze the gonotrophic cycle and to find infection of promastigotes., Results: Phlebotomus wui was identified as the transmitting vector of visceral leishmaniasis in Andier Township, which occupied 99.2% of the sandflies collected. The first and second ten-day period of June was the first peak of its seasonal distribution. Analysis of the gonotrophic cycle revealed that Ph. wui was an exophilic species and appeared nocturnally for feeding with preference to human blood. Natural infection with promastigotes was found in 2 sandflies., Conclusion: Phlebotomus wui is the transmitting vector for visceral leishmaniasis in the newly found endemic area of south Xinjiang.

Objective: To analyze the incidence and the effective prevention and treatment of graft-versus-host disease (GVHD) for the allogeneic peripheral blood stem cell transplantation (allo-PBSCT) for the treatment of leukemia., Methods: Fifty patients with acute leukemia (n = 29) and chronic myeloid leukemia (n = 21) were treated with allo-PBSCT. The conditioning regimens were TBI plus CTX and Vp16 or TBI plus CTX. Two regimens were used for prophylaxis of GVHD: one was the combination of low dose cyclosporine (CsA, 2 - 3 mg x kg(-1) x d(-)1 i.v. or 4 - 6 mg x kg(-1) x d(-1) p.o.) and short course methotrexate (MTX, 15 approximately 10 mg, +1, +3, +6, +11 d) (CsA/MTX group, 32 patients), the other was short course of mycophenolate mofetil (MMF, 1.0 bid, +1 - +28 d) in addition to CsA and MTX (MMF/CsA/MTX group, 18 patients)., Results: All patients were successfully engrafted and the median times to ANC > 0.5 x 10(9)/L and to platelet > 20 x 10(9)/L were 14 (10 - 22) and 20 (10 - 68) days post PBSCT respectively. The incidence of acute GVHD (aGVHD) was 40% (20/50) and of grade III - IV was 12% (6/50). The chronic GVHD (cGVHD) occurred in 22 out of 33 (66.7%) evaluable patients (survived longer than 6 months post PBSCT) and extensive cGVHD in 11 out of 33 (33.3%) patients. Patients with aGVHD displayed significantly higher sIL-2R levels [(277.3 +/- 26.4) U/L] and CD(25)(+) cells [(8.1 +/- 3.4)%] than those without GVHD [(128.1 +/- 96.7) U/L and (3.6 +/- 1.7)%] (P < 0.05). The incidences of aGVHD (16.7%) and extensive cGVHD (9.1%) in MMF/CsA/MTX group were significantly lower than that in CsA/MTX group (53.1% and 45.5%, P < 0.05). The median follow-up duration was 30 (3 - 70) months and 33 patients were still alive. The relapse rate was significantly higher in GVHD negative group (47.1%) than in GVHD positive group (0, P < 0.05). The 3 year disease-free-survival (DFS) rate was 66%., Conclusion: The incidence of aGVHD was low, but of cGVHD was high in allo-PBSCT. sIL-2R and CD(25)(+) cells after PBSCT may provide predictive markers for aGVHD. The MMF/CsA/MTX regimen for prevention of aGVHD in allo-PBSCT is more effective than the CsA/MTX one. There was a strong antileukemic effect of GVHD in the allo-PBSCT.

To investigate the relationship between interleukin-18 (IL-18) and human acute graft-versus-host disease (aGVHD), 26 patients undergoing allogeneic peripheral blood stem cell transplantation (allo-PBSCT) were included in this study. IL-18 secreted by peripheral blood mononuclear cells (MNCs) was measured by enzyme-linked immunosorbent assay (ELISA) before transplantation and during aGVHD. The results showed that grade I GVHD and grades III-IV GVHD developed in 10 and 5 cases, respectively. The levels in the supernatants of MNCs from patients with aGVHD were significantly higher than those in the cases without aGVHD. The levels of IL-18 were correlated with the severity of aGVHD. It is concluded that IL-18 plays an important role in the development of aGVHD.