中心复合设计射线法考察离子液体C16H31ClN2与乐果的毒性相互作用

离子液体(ILs)是一种用于替代传统易挥发有机溶剂的新型"绿色"溶剂.由于不挥发、不会对大气产生污染而得到广泛应用.但是某些ILs易溶于水,其自身毒性能够对生态环境造成潜在影响,这已引起诸多学者对ILs毒性的研究兴趣.然而ILs与其它污染物的毒性相互作用目前研究很少.论文选取咪唑类离子液体C16H31ClN(2DMI)与有机磷杀虫剂乐果(DIM)作为目标化合物,以青海弧菌Q67为检测生物,采用微板毒性分析法测定了目标化合物及其混合物的毒性.为全面考察不同浓度范围DMI与DIM的毒性相互作用,将中心复合设计与固定浓度比射线法有机结合起来构建5个不同浓度比的混合物射线,通过浓度加和与独立作用模型对混合物射线进行比较评估.结果表明在DMI浓度较大且DIM浓度较低时,DMI与DIM之间存在明显拮抗作用,而在其它浓度范围内两者之间为加和作用.     

Invading introduced species in insular heterogeneous environments

We are concerned with the development and analysis of a predator–prey system designed for heterogeneous insular environments; populations are native preys exposed to introduced and invading predators and competitor preys. We first look at the unstructured model; this yields a singular system of ordinary differential equations having interesting dynamical features, such as finite time extinction or persistence of populations. Next we build a spatially heterogeneous structured model upon developing a reaction–diffusion system; then, using numerical experiments we analyze some typical effects of spatial heterogeneities on the persistence or extinction of native or introduced and invading species. The case of Kerguelen sub-Antartic heterogeneous islands where both domestic cats and alien preys have been introduced is taken as an example.     

铁路客车空调换热器的电算法

介绍利用计算机对铁路客车空调换热器进行设计计算,建立空调换热器的数学模型,绘制流程图,根据实际经验指出了编制程序过程中应注意的问题.以CA25B型空调餐车为例,利用所编程序,对其蒸发器按不同的管排列方式分别进行了设计,指出差排比顺排更适用于空调列车.最后得出结论:电算能大大缩短设计时间,提高计算准确度,并能快速对多种方案进行比较而选取换热器的最佳结构形成,达到节能和节约材料的目的.     

Sustainable development indicators: a case study on the city of Flagstaff and Coconino county

The application of capitalist theory and the perception of an autonomous economy have created a range of environmental and social ramifications not addressed via traditional economic reasoning. In order to effectively and efficiently abate sustainability issues, the sustainable development discourse developed evaluation methods such as sustainable development indicators to gauge progress towards sustainability in communities without using traditional cost–benefit methods of analysis. The indicators created in this work are intended to be applied as a method of project evaluation in local community development departments. Using local growth management policy as a basis, these indicators have been designed to show how a development project contributes to policy goals that relate to all three dimensions of sustainability: environmental, economic, and socio-economic.     

Habitat association studies in conjunction with adaptive cluster samples

Habitat association studies investigate the relationships between habitat characteristics and animal usage of study regions. These studies are often conducted in conjunction with surveys designed primarily to estimate population totals. This paper shows that habitat association studies may proceed from surveys using adaptive cluster sampling. The manner in which units appear in the sample turns out not be relevant to the habitat association study, which proceeds as though the units came from a simple random sample. However, it is also shown that the information about the habitat association parameters is greater than one would expect from a simple random sample of the same general size.     

On multiple objective optimization in aquatic ecosystems

Optimal control criteria and hierarchical dynamic control have been designed for a class of structural nonlinear predator-prey models (nutrient-herbivore-predator). The optimal open-loop control of the class of models considered is described. The optimal control design is realized using the hierarchical coordination strategies which are mathematically based on the gradient approach for the interaction prediction principle.     

The effectiveness of marine reserve systems constructed using different surrogates of biodiversity

Biological sampling in marine systems is often limited, and the cost of acquiring new data is high. We sought to assess whether systematic reserves designed using abiotic domains adequately conserve a comprehensive range of species in a tropical marine inter‐reef system. We based our assessment on data from the Great Barrier Reef, Australia. We designed reserve systems aiming to conserve 30% of each species based on 4 abiotic surrogate types (abiotic domains; weighted abiotic domains; pre‐defined bioregions; and random selection of areas). We evaluated each surrogate in scenarios with and without cost (cost to fishery) and clumping (size of conservation area) constraints. To measure the efficacy of each reserve system for conservation purposes, we evaluated how well 842 species collected at 1155 sites across the Great Barrier Reef seabed were represented in each reserve system. When reserve design included both cost and clumping constraints, the mean proportion of species reaching the conservation target was 20–27% higher for reserve systems that were biologically informed than reserves designed using unweighted environmental data. All domains performed substantially better than random, except when there were no spatial or economic constraints placed on the system design. Under the scenario with no constraints, the mean proportion of species reaching the conservation target ranged from 98.5% to 99.99% across all surrogate domains, whereas the range was 90–96% across all domains when both cost and clumping were considered. This proportion did not change considerably between scenarios where one constraint was imposed and scenarios where both cost and clumping constraints were considered. We conclude that representative reserve systems can be designed using abiotic domains; however, there are substantial benefits if some biological information is incorporated.     

Methodological integration for sustainable natural resource management beyond field/farm level: lessons from the ecoregional initiative for the humid and sub-humid tropics of Asia

SUMMARY

Integrated natural resources management (INRM) has to address both the livelihood goals of farmers and the ecological sustainability of agroecosystems and natural resources. Under the Ecoregional Initiative for the Humid and Sub-Humid Tropics of Asia — Ecor(1)Asia — one major set of activities has been the development of approaches, methodologies, and tools to meet the challenges of INRM research for sustainable agricultural development. Examples provided illustrate the role of these methodologies in the three main phases of knowledge development for improving INRM impact: knowledge generation, knowledge capitalization, and knowledge mobilization. The methodologies are designed for better integration across disciplines, spatial scales, and hierarchical levels of social organization. Attempts are made to quantify trade-offs between biophysical sustainability and socio-economic considerations. The case is made for using these methodologies in a more complementary manner to help bridge the topdown and bottom-up approaches in INRM. Inherent in the developing and implementing of these methodologies is the forging of partnerships and fostering linkages with multiple stakeholders, as well as using the knowledge base and integrative tools as communication platforms.     

Urban ecological risk assessment management platform

Due to rapid socioeconomic development in recent years, the influence of human activities on the urban ecosystem and environment is becoming more pronounced, causing increases in accumulated pollutants, resource consumption, and built-up land area. At this time, cities are facing complex ecological threats. We designed a platform to classify and assess the various types of ecological risks that cities and urban agglomerations may encounter. We used PHP to develop a web-based application, with nginx as the platform server, and MySQL to manage the background database. The platform provides users with a clearly structured, visual platform to manage ecological risk. By using this platform, users can quickly identify regional risk sources, find and describe risk factors, and predict possible consequences caused by these risks based on simulation modeling. The forecasting model and database can be synchronously updated and adjusted according to the actual situation. The visual web management platform and user security login system employ the MD5 encryption algorithm. The platform is designed to provide convenient, accurate, and scientific decision-making services for urban planning, construction, environmental protection, and other related areas.     

Efficient synthesis of pyrano[2,3-b]pyridine derivatives using microwave or solar energy

Pyranopyridine derivatives are an important class of heterocyclic compounds due to their biological activities such as antitumor and antibacterial. However, conventional procedures for their synthesis produce large amounts of toxic by-products. Therefore, there is a need to develop simple, efficient and environmentally benign procedures. Here, a one-pot multicomponent protocol is designed for the synthesis of pyrano[2,3-b]pyridone derivatives by reaction of equimolar amounts of 6-hydroxy-1,4-dimethyl-1,2-dihydropyridines, aryl aldehydes and malononitrile, using both microwave heating and solar thermal energy in aqueous EtOH (50%) in the presence of a catalytic amount of K₂CO₃. The products were obtained in 84–90% yields in 10–20 min by microwave heating, and in 90–96% yields in 2–3 h using solar energy.     

Drug delivery systems using pullulan,a biocompatible polysaccharide produced by fungal fermentation of starch

Environmental Chemistry Letters - Advanced drug delivery systems are now designed with biodegradable, biocompatible and non-toxic materials such as polysaccharides. Pullulan is a polysaccharide...     

Multi-scale sustainability evaluation of natural resource management systems: Quantifying indicators for different scales of analysis and their trade-offs using linear programming

The purposes of this paper are: (a) to describe a framework designed for multi-scale sustainability evaluation of Natural Resource Management Systems (NRMS), and (b) to illustrate its application for quantitative analysis using linear programming. The framework described here is intended to contribute to the operationalisation of the concept of sustainability by supporting the processes of design, evaluation and implementation of alternative NRMS at different scales. In this paper, Linear Programming is used for the quantitative analysis of indicators and their trade-offs; using a schematised example, the basic characteristics of the Multi-scale Multiple Goal Linear Programming (M-MGLP) method are described. In M-MGLP, indicators pertaining to different scales of analysis can be set as objectives or constraints for the optimisation. In this way, stakeholders interacting in a specific region can be made aware of the consequences of alternative NRMS in terms of the different indicators at the same scale and/or for indicators at other scales of analysis. The paper ends with a discussion of the main strengths and limitations of the framework and, specifically, of linear programming.     

Bumblebees as model organisms to study male sexual selection in social insects

Social-insect males are often regarded as being merely short-lived "flying sperm containers", which ignores their potential influence on females and paternity patterns as found in other animals. Consequently, social-insect males have received only marginal attention and sexual selection has almost never been studied in these species. Here I present a review of the mating biology of bumblebees (Bombus spp.), which are the best-studied social insects to date. I follow a male's pathway from his birth until he successfully contributes to the next generation, and show that males have evolved adaptations and behaviors to influence paternity patterns at various stages of their life, which are similar to those exhibited by males of non-social insects. By comparing the available bumblebee data with more sparse studies of male reproductive behavior in other social Hymenoptera, I argue that such male adaptations may indeed be widespread in social insects. I suggest that current paradigms on sexual selection should be challenged by using social insects as model systems, because they offer unique features, and a solid theoretical background in which clear predictions can be made and appropriate experimental tests of them can be designed.Communicated by A. Cockburn     

Florida, USA, Port Experience with Marpol Annex V

This study assesses the effectiveness of MARPOL Annex V regulations, hereafter referred to as the Annex, using observations of United States Department of Agriculture (USDA) personnel stationed at major Florida ports. the study was initiated at the request of the 1IOPS Marine Debris Workshop Steering Committee* and was designed to focus on Gulf and Caribbean experiences gained since the Annex became effective.     

主成份分析在城市生态经济动态评价中的应用

城市生态经济的动态发展过程,可以看作多种生态关系要素相互作用的集合沿时序轴波动的轨迹.在这种多变量分析中,完全采用人工筛选变量的方法难以避免确定权重等过程所带来的主观干扰.PCA(主成份分析)采用一种特殊的转换降维方法,根据原始数据自身的特点综合成几个主导因子,并最大程度反应原始数据的信息量.本文根据天津市四十年18项生态经济指标,采用相关矩阵和PCA双重筛选过程,得到载荷量大于90%的前三个主分量,将其作为天津市生态经济动态评价的基础.结果表明:天津市解放后四十年每十年一次的经济周期上迭加了自然社会等非经济因素的影响,表现出城市生态经济动态发展的三大阶段,这种发展主要受到宏观经济管理模式及其相应的投资机制的制约.     

Coastal dynamics and adaptation to uncertain sea level rise: Optimal portfolios for salt marsh migration

The sustainability of dynamic natural systems often depends on their capacity to adapt to uncertain climate-related changes, where different management options may be combined to facilitate this adaptation. Salt marshes exemplify such a system. Marsh sustainability under rapid sea level rise requires the preservation of transgression zones - undeveloped uplands onto which marshes migrate. Whether these uplands eventually become marsh depends on uncertain sea level rise and natural dynamics that determine migration onto different land types. Under conditions such as these, systematically diversified management actions generally outperform ad hoc or non-diversified alternatives. This paper develops the first adaptation portfolio model designed to optimize the benefits of a migrating coastal system. Results are illustrated using a case study of marsh conservation in Virginia, USA. Results suggest that models of this type can enhance adaptation benefits beyond those available through current approaches.     

Parameter fitting in dynamic models

We consider the numerical approaches for the least squares estimation of the parameter vector p in the initial value problem y′ = g(t, y, p), y(t₀) = y₀(p) when observations are available on some or all components of the vector y(t). Special attention is paid to the development of techniques which, although not global, are less sensitive to initial parameter estimates than the standard approach employing the sensitivity equations. Experience indicates that interactive approaches can be very valuable when good starting parameter approximations are unavailable. We describe the main features of our interactive parameter fitting package PARFIT. This package contains standard techniques employing the sensitivity equations as well as special algorithms designed to improve poor parameter estimates. These special algorithms have been selected and developed with user interaction in mind. We describe in detail one special approach designed for the case when observations are not available on all state variables. An example (using computer generated observations) is presented to illustrate this approach. Finally, the power of an interactive approach is demonstrated with two examples involving attempts to model physically observed phenomena.     

基于STC12C5410AD的电铃无线控制系统

针对传统电铃采用单一作息时间表进行专线控制的缺点,设计了一种能无线控制、又能同时存储多个作息时间表的电铃控制系统．该系统用无线代替专线,存储有多个时间表,在季节变更时通过控制器自动变换表,解决了传统电铃控制系统中的专线成本高、维修难、季节变换需要人工改表的问题．图5,表2,参4．     

Prioritizing Pacific Salmon Stocks for Conservation

Over 300 native stocks of Pacific salmon, steelhead, and coastal cutthroat trout (Oncorhynchus spp.) are at risk of extinction in the Pacific Northwest. With only limited resources available for conservation and recovery, prioritization of these stocks may become necessary if meaningful measures are to be implemented. We propose criteria by which prioritization may be guided. First, we rank stocks for risk of extinction, either by population viability analysis or by a set of surrogate measures. Then we rank stocks for biological consequences of extinction, using sets of questions designed to establish the genetic and evolutionary consequences and the ecological consequences if a stock were to become extinct. Together, these rankings allow stocks to be prioritized for a range of possible actions, with those stocks at highest risk and bearing the greatest biological consequences of extinction receiving attention first. Application of the prioritization process to 20 Pacific anadromous salmonid stocks worked as intended, although data limitations are considerable. The process is most likely to work successfully when applied to many stocks on which data exist, when several experts carry out the prioritization, and when the results are peer reviewed.