关于我国新兽药研究开发的战略思考

以提高自主创新能力为主题，分析了我国兽药研究开发现状，提出了今后我国兽药行业及生产企业进行新兽药研究开发的战略目标设想、内容和建议。     

超抗原及其在兽医科学上的应用

超抗原以极低的浓度就能引起机体免疫细胞、细胞因子和抗体的巨大变化,引起机体一系列病理生理过程。鉴于超抗原的这种特性,医学上已成功将其用于癌症和病毒病的辅助治疗。在兽医科学上,超抗原有望在兽医病理学、兽医药理学、兽医临床治疗和兽医预防方面得到广泛的应用。     

陕北黄土高原生态资产与区域生态安全程度研究

在GIS支持下,通过测定陕北黄土高原植被生产和生态调节的物质量及生态资产价值.结果表明:①通过计算,陕北黄土高原每年的生态资产总价值为7.00×1010元,其中释放氧气的价值最高,占总价值的29.51%;土壤保持价值最小,占总价值的1.5%.而就植被类型而言,果树的生态价值最高,占总价值的43.89%;最小是沼泽,占总价值的0.4%.②通过地理信息系统与生态学的结合,对陕北黄土高原的生态资产进行定量测量,并利用GIS软件的空间分析功能,绘制了陕北黄土高原生态资产价值空间分布图.③陕北黄土高原生态安全程度为0.45,处于生态不安全状态,负荷超载,要狠抓生态建设.④针对陕北黄土高原环境现状,提出相应的治理对策.     

The availability of state-level data on interstate cattle movements in the United States

Knowledge about the patterns of animal movement – particularly feeder-cattle movement – within the USA is necessary in order to anticipate how diseases might be spread geographically. This study was conducted to explore the availability of interstate-level movement data which might be used to develop a more coherent national picture of interstate feeder-cattle movement. State Statistical Offices of the National Agricultural Statistics Service, 1996 (NASS) and Departments of Agriculture in all 50 states were contacted to determine the type of information collected regarding the import and export of feeder cattle. Eighteen of the 50 states contacted recorded updated import and export information by using certificates of veterinary inspection and (occasionally) entry permits for verification. The 18 states were: Alabama, Colorado, Florida, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Maryland, Massachusetts, Minnesota, New Jersey, Pennsylvania, Texas, West Virginia, Wisconsin, and Wyoming. Profiles of import and export data from Kansas, Texas, Colorado and Iowa (the primary receivers of 51% of total 1995 imports) were developed. These four states received at least 50% of their cattle imports from <9 different states. As a result, approximately half of the nation's import movement can be explained by a total of 13 states and Mexico (excluding duplicates). Also, >50% of the exports from Kansas, Texas, Colorado, and Iowa go to ≤3 states. This import and export information confirms conclusions of others that cattle tend to move toward the center of the USA. However, if more states kept comprehensive, up-to-date records of movement information, knowledge about cattle-movement patterns in the USA would be importantly increased. The lack of specific notations on certificates of veterinary inspection can lead only to perceived trends; the present records have limited value in tracking animal movement.     

Quantifying the nitrogen retention capacity of natural wetlands in the large-scale drainage basin of the Baltic Sea

We estimate the nitrogen retention capacity of natural wetlands in the 1.7 million km² Baltic Sea drainage basin, using a wetland GIS data base. There are approximately 138,000 km² of wetlands (bogs and fens) in the Baltic Sea drainage basin, corresponding to 8% of the area. The input of nitrogen to natural wetlands from atmospheric deposition was estimated to 55,000–161,000 ton y¹. A map of the deposition of both wet and dry nitrogen is presented. The input from the human population was estimated to 255,000 ton y¹ in terms of excretory release in processed sewage water. There may also be leakage from forests and agricultural land into the wetlands. Due to lack of data on hydrology and topography, such potential nitrogen sources are not accounted for here. The capacity of the wetlands to retain the atmospheric deposition of nitrogen was estimated to 34,000–99,000 ton y¹. The potential retention by wetlands was estimated to 57,000–145,000 ton y¹ when the nitrogen input from the human population was added. If drained wetlands were to be restored and their area added to the present wetland area, the nitrogen retention capacity was estimated to increase to 196,000–261,000 ton y¹. Our results indicate that existing natural wetlands in the Baltic Sea drainage basin annually can retain an amount of nitrogen which corresponds to about 5–13% of annual total (natural and anthropogenic) nitrogen emissions entering the Baltic Sea. The ecosystem retention service performed by wetlands accounts for a substantial nitrogen removal, thereby reducing the eutrophication of the Baltic Sea.     

A spatially-explicit method to assess the dry deposition of air pollution by urban forests in the city of Florence,Italy

Urban forests (UF) provide a range of important ecosystem services (ES) for human well-being. Relevant ES delivered by UF include urban temperature regulation, runoff mitigation, noise reduction, recreation, and air purification. In this study the potential of air pollution removal by UF in the city of Florence (Italy) was investigated. Two main air pollutants were considered – particulate matter (PM₁₀) and tropospheric ozone (O₃) – with the aim of providing a methodological framework for mapping air pollutant removal by UF and assessing the percent removal of air pollutant.The distribution of UF was mapped by high spatial resolution remote sensing data and classified into seven forest categories. The Leaf Area Index (LAI) was estimated spatially using a regression model between in-field LAI survey and Airborne Laser Scanning data and it was found to be in good linear agreement with estimates from ground-based measurements (R² = 0.88 and RMSE% = 11%). We applied pollution deposition equations by using pollution concentrations measured at urban monitoring stations and then estimated the pollutant removal potential of the UF: annual O₃ and PM₁₀ removal accounted for 77.9 t and 171.3 t, respectively. O₃ and PM₁₀ removal rates by evergreen broadleaves (16.1 and 27.3 g/m²), conifers (10.9 and 28.5 g/m²), and mixed evergreen species (15.8 and 31.7 g/m²) were higher than by deciduous broadleaf stands (4.1 and 10 g/m²). However, deciduous forests exhibited the largest total removal due to the high percentage of tree cover within the city. The present study confirms that UF play an important role in air purification in Mediterranean cities as they can remove monthly up to 5% of O₃ and 13% of PM₁₀.     

基层图书馆为弱势群体服务的现状与思考——以徐州地区为例

在分析弱势群体构成和文化需求的基础上,以徐州地区为例论述了基层图书馆为农村弱势群体服务的若干举措和实践活动,探讨为农村弱势群体服务的方式方法,并对今后工作提出具体建议。     

林地定额管理系统分析与实现

林地是森林资源的重要组成部分,如何有效地对林地进行管理,对于实现胡锦涛总书记提出的到2020年我国森林面积和蓄积量比2005年分别增加4 000万hm2和13亿m3的林业双增目标具有重要意义。而林地定额管理是林地管理的一个重要组成部分。目前的林地定额管理主要依靠各省人工逐笔核算和月末上报的方式,不仅存在一定的时滞性,而且还可能出现超额使用林地定额情况。针对以上弊端,深入分析和研究林地定额的细分规则,提出一种基于面向服务的体系结构(SOA)架构的林地定额管理系统。不仅解决了时滞性,实现对林地定额的实时管理与监控,而且还能灵活地解决林地定额管理中出现的一些特殊情况。     

图书馆信息服务的优化

图书馆信息服务的优化是维护并促进图书馆事业可持续发展的关键,文献的多元性、文化的多样性以及生存环境的丰富性为其提供了拓展的空间.围绕这一主题进行阐述,分析了全新的信息环境下,拓展和延伸图书馆信息服务的必要性和优化的方式,希望借此对图书馆信息服务的发展有所助益.     

Relating tradable credits for biodiversity to sustainability criteria in a dynamic landscape

Tradable biodiversity credit systems provide flexible means to resolve conflicts between development and conservation land-use options for habitats occupied by threatened or endangered species. We describe an approach to incorporate the influence of habitat fragmentation into the conservation value of tradable credits. Habitat fragmentation decreases gene flow, increases rates of genetic drift and inbreeding, and increases probabilities of patch extinction. Importantly, tradable credit systems will change the level of fragmentation over time for small and/or declining populations. We apply landscape equivalency analysis (LEA), a generalizable, landscape-scale accounting system that assigns conservation value to habitat patches based on patch contributions to abundance and genetic variance at landscape scales. By evaluating habitat trades using two models that vary the relationship between dispersal behaviors and landscape patterns, we show that LEA provides a novel method for limiting access to habitat at the landscape-scale, recognizing that the appropriate amount of migration needed to supplement patch recruitment and to offset drift and inbreeding will vary as landscape pattern changes over time. We also found that decisions based on probabilities of persistence alone would ignore changes in migration, genetic drift, and patch extinction that result from habitat trades. The general principle of LEA is that habitat patches traded should make at least equivalent contributions to rates of recruitment and migration estimated at a landscape scale. Traditional approaches for assessing the “take” and “jeopardy” standards under the Endangered Species Act based on changes in abundance and probability of persistence may be inadequate to prevent trades that increase fragmentation.