Purification and characterization of an alkaline protease from Acetes chinensis

An alkaline protease from Acetes chinensis was purified and characterized in this study. The steps of purification include ammonium sulfate precipitation, ion-exchange chromatography with Q-sepharose Fast Flow, gel filtration chromatography with S300 and the second ion-exchange chromatography with Q-sepharose Fast Flow. The protease was isolated and purified, which was present and active on protein substrates (azocasein and casein). The specific protease activity was 17.15 folds and the recovery was 4.67. The molecular weight of the protease was estimated at 23.2 kD by SDS-PAGE. With azocasein as the susbstrate, the optimal temperature was 55°C and the optimal pH value was 5.5. Ion Ca²⁺ could enhance the proteolytic activity of the protease, while Cu²⁺, EDTA and PMSF could inhibit its activity.     

山东省省级基础地理信息系统建设探讨

前言 基础地理信息的生产提供和更新维护,一直是各级测绘行政主管部门履行基础测绘保障的重要职能。按照《中华人民共和国测绘法》和《山东省测绘管理条例》规定,基础测绘实行分级管理。其中,省级基础地理信息系统的建设、维护与更新,是省级基础测绘工作的主要内容。     

土地利用规划环境影响评价中不确定性分析

在分析土地利用规划环境影响评价中的不确定来源、特点及其对决策的影响基础上,提出了降低环境影响评价中不确定性的方法。通过研究认为:土地利用规划环境影响评价中的不确定主要由土地利用规划方案的不确定、环境信息的不确定和环境影响程度的不确定引起的,这些不确定性具有客观性、传递性、累积性,对决策会产生较大的干扰,但是可以通过使用基于情景分析的预测方法、多方协作的方式以及广泛开展公众参与等方法来降低。     

莒县农村居民点整理潜力研究

1农村居民点用地存在的问题1.1平房户型多且分散建筑容积率低莒县农村居民点户型中平房比重高达98.6%,二层楼房占1.1%,三层及以上户型仅占0.3%,建筑容积率低,单层平房占到98.6%,分布分散,有10个乡镇的农村居民点密度低于日照市平均水平。农村居民点用地“平面扩张有余,立体利用     

New Damage-locating Method for Bridges Subjected to a Moving Load

A new damage-locating method for bridges subjected to a moving load is presented, and a new ‘moving load damage-locating indicator＇ （MLDI） is introduced. A vehicle is modeled as a moving load, the bridge is simplified as an Euler-Bernoulli beam, and the damage is simulated by a reduction of stiffness properties of the elements. The curvature and MLDI values at each node of the baseline model （undamaged） and the damage model are computed respectively. Then the damage or damages can be located from a sudden change of the MLDI value. The feasibility and effectiveness of the proposed method are validated by numerical simulation. The results indicate that the method is effective, being able to not only locate a single damage accurately, but also locate multiple damages in simply-supported bridges, including multiple damages in continuous bridges. The results also indicate that the MLDI can accurately locate damages under 5% measurement noise.     

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Screening of marine fungus from Nanji Island and activity of their metabolites against pathogenic Vibrio from Pseudosciaena crocea

Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island,Wenzhou,Zhejiang Province,China.Antibacterial screening using the agar disc method showed that 19 of the isolated strains could inhibit at least one pathogenic Vibrio from Pseudosciaena crocea.Subsequent screening confirmed that nine strains produced antibacterial metabolites that had activity against one or several types of pathogenic Vibrio.Strain NJ0104 had the widest antimicrobial spectrum and strong activity,particularly against Vibrio parahaemolyticus-MM0810072.A preliminary study of NJ0104 antibacterial metabolites demonstrated that they had thermal stability up to 80°C,ultraviolet stability up to 40 min and pH stability between 4.0-7.0.In addition,the antibacterial metabolites were readily soluble in butanol.To identify the specific strain,the ITS-5.8S rDNA regions of NJ0104 were PCR amplified and sequenced.Based on the combination of phenotypic and genotypic data,the strain was identified as Arthrinium sp.     

Current status of small yellow croaker resources in the southern Yellow Sea and the East China Sea

We used data from bottom trawl surveys to study the factors influencing the abundance of small yellow croaker, Larimichthys polyactis, in the southern Yellow Sea (SYS) and the East China Sea (ECS). The resource density index (RDI) was generally higher in summer and autumn than in spring and winter. RDIs were also significantly greater in the SYS than in the ECS in summer and autumn. The bottom water salinity and depth of spatial distribution of small yellow croaker was similar between the two areas in summer, but different in other seasons. Regression analysis suggested that environmental factors such as bottom water temperature, salinity, and depth influenced the RDIs in summer in these areas. Growth condition factor (GCF) in the two areas varied monthly and the croaker in the SYS grew more slowly than those in the ECS. This was likely due to the low bottom temperature of the Yellow Sea Cold Water Mass in summer and autumn or to higher human fishing pressure in the ECS. To ensure sustainable utilization of the croaker stocks in these regions, we recommend reducing the fishing intensity, increasing the cod-end mesh size, and improving the protection of juveniles.