秦岭北麓区域主要河流水质分析与评价

通过野外调查取样和室内实验检测,分析和评价了秦岭北麓主要河流的水质现状,结果表明:①区域内河流污染成分主要以有机污染为主,其次是金属污染,金属污染主要以铅、汞污染为主。②在检测的41个河段中,按综合污染指数大小分级,共计有56.10%的河段受到不同程度的污染,其中,水质严重污染的河段占7.32%,水质重污染的河段占14.63%,水质轻污染的河段占34.15%;共计有43.90%的河段水质较好,其中,水质尚清洁的河段占34.15%,水质清洁河段占9.76%。③区域内水污染已较为严重,使得河流水环境承载能力降低,水环境安全已经受到一定程度的威胁。     

老挝本地山羊及其第一代杂交山羊的生长函数测定

【目的】估测老挝本地山羊（Eat）及Bach Thao×Lat第1代杂交羊的生长曲线。【方法】于2009-2010在老挝Attapeu和vientience省进行两次调查收集数据,以山羊活体重作为年龄的函数。首先对有关性状进行方差分析以确定基因型、性别和年龄对活体重效应的显著性。对每种类型的山羊均采用线性和非线性（Gompertz）生长模型进行分析。【结果】数据初始方差分析的结果表明,基因型和性别对山羊活体重有显著影响,因此相关数据被分别用于每种基因型的雌、雄山羊生长曲线的绘制。结果表明,1年以下的山羊的两种回归生长模型的决定系数（R^2）均较高（〉99％）且表现相似;但是,对于1年以上的山羊,Gompertz生长模型的R。较高,其拟合程度高于线性模型（R。较低）。以建立的Gompe~z生长模型对不同基因型山羊进行分析,结果表明,Lat雌山羊和雄山羊的成熟体重分别为23．93、29．93kg,Bach Thao×Lat第1代杂交母山羊和公山羊的体重分别为32．66、37．69kg。【结论】非线性Gompertz生长模型比较适合于评价不同年龄的老挝本地山羊和Bach Thao×Lat第1代杂交山羊的活体重。     

Determination Method and Criterion for Voids by Dynamic Deflection Difference in the Same Cement Slab

Aiming at the lack of the current determination method for voids in practical engineering applications, in order to accurately quantify the voids beneath cement slab, the determination method was proposed with slab edge slab center deflection difference and slab corner slab center deflection difference in the same cement slab for voids.Three dimensional models were set up using the ANSYS finite element method for voids beneath slab corner and slab edge.And the load was simulated with FWD test results.Thereafter, the deflection values were calculated in slab center, slab corner, slab edge under different void depth, void area and load transfer capacity.And the range of deflection diffidence was obtained.With Yantai Weihai expressway, detection data for deflection using Falling Weight Deflectometer were statistically analyzed.And the criteria and correction factors of load transfer capacity were given with simulation and samples analysis.The feasibility of criteria was verified by actual test data.It is found that the simulation values and the test values are in good agreement.The accuracy of void determination by lab edge slab center deflection difference and slab corner slab center deflection difference are 88.5% and 84.6%, respectively, which meet the engineering requirements.The voids were determined under the same conditions with the elimination of deflection variability.     

The decoloration mechanism of Methylene Blue in a CuO/TiO2-H2O2 photocatalytic system

A CuO/TiO2 photocatalyst is prepared using the hydrolysis method. It exhibites excellent photocatalytic activity under both UV and Vis light. After investigating the quantity of hydroxyl radicals and the decoloration rate under different pH sit     

Improved simulation of winter wheat yield in North China Plain by using PRYM-Wheat integrated dry matter distribution coefficient

The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China. Presently, most remote sensing process models use the “biomass×harvest index(HI)” method to simulate regional-scale winter wheat yield. However, spatiotemporal differences in HI contribute to inaccuracies in yield simulation at the regional scale. Time-series dry matter partition coefficients(Fr) can dynamically reflect the dry matter partition...     

Calcium supplementation in low nutrient density diet for meat ducks improves breast meat tenderness associated with myocyte apoptosis and proteolytic changes

To define the relationship between dietary nutrient density, calcium(Ca), and meat quality in meat ducks. A total of 288 male Cherry Valley SM3 medium ducklings were fed a common standard starter diet until d 14. At 15 d of age, ducks were randomly divided into 2 treatment groups and fed either a conventional diet or a low nutrient density(LND) diet. Compared with the conventional diet, the energy was reduced in the LND diet by 8.6% and 16.8% in grower(15 to 35 d) and finisher(36 to 56 d) phases...     

我国水产种业发展的几点思考

对我国水产种业发展的现状进行了总结与评价,对水产种业发展的机遇与挑战进行了分析。根据国家水产业发展的有关文件和产业发展趋势,从科技创新、体系建设和政策措施方面提出了加快水产种业发展的建议。     

ELISAs based on rNcGRA7 and rNcSAG1 antigens as an indicator of Neospora caninum activation

Bovine abortion caused by the Apicomplexa parasite Neospora caninum is a major economical problem in the livestock industry worldwide. However, the relationship between N. caninum infection and abortion is still unknown. Our study aimed to elucidate the relationship between parasite-specific antibody responses, parasite stages and abortion. In experimentally infected cattle, anti-NcGRA7 IgG1 antibody was predominantly detected during the acute infection stage, while the production of anti-NcSAG1 IgG1 antibody was observed during both acute and chronic stages. Furthermore, levels of anti-NcGRA7 IgG2 antibody were lower than those of anti-NcSAG1 IgG2 antibody. When tested on cattle with Neospora-associated abortion, positive rates of the anti-NcGRA7 IgG2 antibody were significantly lower than those of the anti-NcSAG1 antibody, although there was no difference in IgG1 antibody-positive rates between the two antigens. In addition, anti-NcGRA7 IgG2 antibodies were not detected in cattle for more than 30days after abortion. Our results suggested that anti-NcGRA7 and anti-NcSAG1 antibodies are suitable indicators for the activation stage of N. caninum infection and broad detection of the infection, respectively. In conclusion, the use of recombinant NcGRA7 and NcSAG1-based ELISAs will be useful for evaluating the abortion risk associated with N. caninum infection.     

Evaluation of enzyme-linked immunosorbent assays with recombinant antigens for the serodiagnosis of equine Babesia infections

Two enzyme-linked immunosorbent assays (ELISA) with recombinant protein as antigens were evaluated by comparison with the indirect fluorescent antibody tests (IFAT) for the detection of specific antibodies to Babesia caballi and Babesia equi, respectively in 380 sera from experimentally infected, uninfected, and field horses. The high concordances of 92.4% (351/380) and 98.2% (373/380) between ELISA and IFAT for B. caballi and B. equi, respectively suggest that ELISA, especially for B. equi infection, could be alternative to the corresponding IFAT for serodiagnoses of equine piroplasmosis, although some improvements are required in ELISA for B. caballi.     

Clinical usefulness of antibodies against Babesia gibsoni detected by ELISA with recombinant P50

The clinical usefulness of antibodies against Babesia gibsoni detected by ELISA with recombinant P50 was examined in dogs in an area where B. gibsoni infection was endemic. Only 8 among 14 dogs with acute type B. gibsoni infection without a previous history of infection were positive. This high percentage of false-negative results is thought to be a weak point of ELISA as a diagnostic tool. However, 14 other anemic dogs with a confirmed history of B. gibsoni infection were all positive, thus confirming the higher sensitivity of ELISA in detecting a history of infection.