皮肤刺激实验替代模型的研究新进展

皮肤刺激性是日常使用化妆品最常见的不良反应之一。人类健康相关产品危险性评价常做皮肤刺激性实验,皮肤刺激性试验是化妆品原料及产品安全性评价的主要项目。传统皮肤刺激试验采用实验动物进行,2013年3月11日欧盟已经禁止销售基于动物实验研发的化妆品原料及产品.随着组织工程技术和现代生物技术的发展,多种替代动物试验的体外模型被开发和应用,新的的皮肤刺激物陆续被发现。欧盟多采纳重组人表皮实验方法作为新体外皮肤实验指南(包括模型Episkin和模型Epiderm),随着体外模型重建技术的不断改善,不仅拓展了皮肤模型的临床应用范围,也必然推动新的敏感而特异的皮肤标志物的发现和应用。     

动物细胞培养和细菌发酵的工艺经济学:组织型纤溶酶原激活剂的一例研究的分析

工艺决定产品,拿最近批准进入市场的tPA来说,它的售价是2200美元/剂量,是链激酶的近20倍,因而降低生产成本对这些产品是至关重要的。由于生化工程学家没有现成的生化工艺规律可循,在放大规模之前他们要做细致的小规模试验。这篇文章就通过分析一例研究,来说明决定一种产品的重要工艺、设计和经济学方面的考虑。1 模型工艺和生产系统的选择 我们选择tPA的生产作为模型工艺,因为它被认为是年轻的生物技术产业的先驱产品;同时也是第一个经过基因工程改造的哺乳动物细胞生产的上市药     

对市场营销中销售区域划分的几点认识

在市场营销活动中,有些产品需要分销才能到达消费者手中,特别是快速消费品更需要分销才能进入市场。在产品分销中,一个重要的问题就是如何划分销售区域。划分销售区域有利于明确责任、提高士气、降低销售成本和改善客户关系。     

同龄纯林自然稀疏过程的经验模型研究

应用-3/2法则及广义Schumacher生长方程导出同龄纯林自然稀疏过程中密度随时间变化规律新模型,采用遗传算法对非线性模型参数进行最优估计.以山杨、云南松、杉木等树种同龄纯林自疏过程中密度随时间变化资料对新模型进行了验证,并与前人提出的主要森林自疏过程密度随时间变化规律模型进行了对比.结果表明,所提出的同龄纯林自疏规律模型能很好地拟合实际观测资料,具有良好的使用价值;新模型拟合效果较前人提出的自疏规律模型效果均更佳,说明新模型是一个描述同龄纯林自疏过程密度随时间变化规律的理想经验模型,可在森林自疏规律研究中应用.杉木林自疏过程密度变化规律的研究可为南方林区杉木林经营管理提供参考.     

强化在华内窥镜、生物显微镜的服务体制 奥林巴斯(北京)销售服务有限公司宣告成立

———合并本地销售代理商,在华设立24家分支机构,加强与客户的接触———为了在持续扩大的中国市场上增加内窥镜和生物显微镜的销售,奥林巴斯株式会社(社长:菊川刚)合并了中国本地销售代理商,在北京设立了奥林巴斯(北京)销售服务有限公司(Olympus(Beijing)Sales&ServiceCo.,Ltd.),并已于2004年7月1日正式开始营业。在整个亚洲地区,中国市场无疑是发展最为迅猛的市场之一。奥林巴斯在中国也成立了从事数码相机等消费类产品的生产、销售和市场开拓的子公司,在中国开展了全面的直销活动并取得了良好的销售业绩。除了消费类产品之外,内窥镜…     

对企业如何做好赊销管理的几点探讨

企业将产品卖出去并不等于销售成功,成功的销售是产品转变成现金,而不是产品转变成债权。在现代市场经济条件下,随着市场竞争不断加剧,生产企业为了扩大市场份额,增加销售量,越来越多地采用赊销方式,已逐步成为惯例和企业竞争的重要手段。企业的销售部门和财务部门要了解赊销产生的原因,有针对性地采取有效的措施,才能提高赊销管理水平。     

农田环境空间异质性及农作物生产安全风险评价方法研究—以蔬菜生产为例

对贵州省遵义县有代表性的蔬菜地土壤重金属进行了研究和示范性评价.采用Kriging方法估计了目标地块中Cd和Pb的分布,结果显示它们存在较大的空间异质性.土壤重金属危害人体健康主要是通过食用富集重金属的农产品而产生的.为了正确地估计这种土壤重金属危害人体健康的方式,需要将蔬菜对重金属的富集规律和食品安全标准相结合建立评价模型.据此,构建了单因子和多因子评价模型和风险模型.根据实验数据(徐明飞等,2008)建立了9个蔬菜品种对Cd、Pb富集的模型,用该模型与无公害蔬菜产品标准相结合对目标地进行了评价.评价结果表明:在目标地块上生产的黄瓜、长瓜、丝瓜、番茄、萝卜和莴笋产品是安全的,即无风险(p=0);Cd对辣椒产品风险很小(p=0.0023);Cd对茄子产品有一定风险(p=0.4145),而Pb对两者均无风险(p=0);Cd和Pb对青菜产品有巨大风险(p=0.9821或p=0.96961).     

Transgenic Sciences购买毒理实验室

Transgenic Sciences公司(马萨诸塞州的Worcester)(一家研究转基因疾病模型和毒理学试剂的新开张的公司)计划花7百万元的股票和现金(可能大部分为股票,因为Transgenic只有不到3百万的资金)购买新英格兰最大的毒理学实验室——Mason研究所,这项收购计划将给Transgenic未来的产品提供一个现成的销售部门。在马萨诸塞州Worcester的Mason研究所雇用了140人在110 000平方英尺的设施内工作,去年8百万美元的收入来自新药和医疗设备的综合安全和效益测试;毒理和致癌     

生态对策影响种群增长的数学模型研究

本文根据不同生态对策的种群的增长特点和Alllee规律,组建了一个能反映种群自我调节机制以及这种机制与环境负荷协同作用对种群施加影响的种群增长模型。模型在变化其参数时,可以转变为几个具有实用价值的模型。因此,该模型具有一定的应用意义。文章最后还讨论了该模型对生态管理的指导意义。     

以比生长速率时间曲线为基础的生物群体生长数学模型

构建了一个描述限制性环境条件下生物群体生长规律的数学模型。模型中比生长速率(μ)是时间(t)的函数。模型可以很好地拟合多种生物或生物细胞群体生长的延迟期、指数期和稳定期。该模型参数少,模型参数生物学意义明确,计算简单。     

Demand and Dematerialization Impacts of Second-Hand Markets

The potential for second-hand markets to reduce demand for new goods is investigated. Using a variant of an economic model originally developed by Anderson and Ginsburgh, the physical implications for material use are explored. The second-hand market grows if transaction costs decrease or if product lifetime increases. In this model, growth of the secondhand market reduces demand for new goods if there are waste used goods that can be brought into the market. But if there is not a ready supply of waste used goods, growth of the second-hand market can increase demand for new goods, thereby increasing material consumption. Moreover, even when second-hand sales reduce demand for new goods, it is typically not on a one-for-one basis. The extent to which the purchase of used goods replaces the purchase of new goods is shown to be an explicit function of the relative value provided by used versus new goods.     

THEORY FOR THE EVOLUTION OF DIFFUSIBLE EXTERNAL GOODS

Organisms from prokaryotes to plants and animals make costly investments in diffusible beneficial external products. While the costs of producing such products are born only by the producer, the benefits may be distributed more widely. How are external goods‐producing populations stabilized against invasion by nonproducing variants that receive the benefits without paying the cost? This question parallels the classic question of altruism, but because external goods production need not be altruistic per se, a broader range of conditions may lead to the maintenance of these traits. We start from the physics of diffusion to develop an expression for the conditions that favor the production of diffusible external goods. Important variables in determining the evolutionary outcome include the diffusion coefficient of the good, the distance between individuals, and the uptake rate of the external good. These variables join the coefficient of relatedness and the cost/benefit ratio in an expanded form of Hamilton's rule that includes both selfish and altruistic paths to the evolution of external goods strategies. This expanded framework can be applied to any external goods trait, and is a useful heuristic even when it is difficult to quantify the fitness consequences of producing the good.     

Evolutionary game theory meets social science: Is there a unifying rule for human cooperation?

Evolutionary game theory has shown that human cooperation thrives in different types of social interactions with a PD structure. Models treat the cooperative strategies within the different frameworks as discrete entities and sometimes even as contenders. Whereas strong reciprocity was acclaimed as superior to classic reciprocity for its ability to defeat defectors in public goods games, recent experiments and simulations show that costly punishment fails to promote cooperation in the IR and DR games, where classic reciprocity succeeds. My aim is to show that cooperative strategies across frameworks are capable of a unified treatment, for they are governed by a common underlying rule or norm. An analysis of the reputation and action rules that govern some representative cooperative strategies both in models and in economic experiments confirms that the different frameworks share a conditional action rule and several reputation rules. The common conditional rule contains an option between costly punishment and withholding benefits that provides alternative enforcement methods against defectors. Depending on the framework, individuals can switch to the appropriate strategy and method of enforcement. The stability of human cooperation looks more promising if one mechanism controls successful strategies across frameworks.     

Evolution in group-structured populations can resolve the tragedy of the commons

Public goods are the key features of all human societies and are also important in many animal societies. Collaborative hunting and collective defence are but two examples of public goods that have played a crucial role in the development of human societies and still play an important role in many animal societies. Public goods allow societies composed largely of cooperators to outperform societies composed mainly of non-cooperators. However, public goods also provide an incentive for individuals to be selfish by benefiting from the public good without contributing to it. This is the essential paradox of cooperation-known variously as the Tragedy of the Commons, Multi-person Prisoner's Dilemma or Social Dilemma. Here, we show that a new model for evolution in group-structured populations provides a simple and effective mechanism for the emergence and maintenance of cooperation in such a social dilemma. This model does not depend on kin selection, direct or indirect reciprocity, punishment, optional participation or trait-group selection. Since this mechanism depends only on population dynamics and requires no cognitive abilities on the part of the agents concerned, it potentially applies to organisms at all levels of complexity.     

Smallholder rubber and swidden agriculture in Borneo: A sustainable adaptation to the ecology and economy of the tropical forest

This is a study of the role of Para rubber cultivation in a system of swidden agriculture in Indonesian Borneo. Such smallholdings produce most of Indonesia’s rubber, which is the country’s largest agricultural generator of foreign exchange. Rubber integrates well into Bornean systems of swidden agriculture: the comparative ecology and economy of Para rubber and upland swidden rice result in minimal competition in the use of land and labor — and even in mutual enhancement — between the two systems. Rubber occupies a distinct niche in the farm economy: it meets the need for market goods, while the swiddens meet subsistence needs. The intensity of production on these smallholdings is, as a result, characteristically low (and may even vary inversely with market prices). This reflects the independence of these smallholders from external economic and political influences, which has been the key to their historical success. The special virtues of such “composite systems” merit greater attention by development planners. Penilitian ini mempelajari peranan karet rakyat sebagai pasangan bagi sistem perladangan di Kalimantan-Indonesia. Perkebunan karet rakyat merupakan penghasil utama karet Indonesia, yang merupakan penyumbang pertanian terbesar bagi devisa negara. Karet rakyat membaur dengan baik dalam sistem perladangan di Kalimantan: pembandingan ekologi dan ekonomi antara karet rakyat dan sistem perladangan menunjukkan persaingan yang minimum dalam pemakaian lahan dan tenaga kerja—dan bahkan saling menguntungkan—antara kedua sistem tersebut. Karet rakyat menempati kedudukan yang penting dalam ekonomi usaha para peladang: yaitu memenuhi kebutuhan barang-barang pasar, sedangkan sistem perladangan memenuhi kebutuhan pokok hidup. Intensitas produksi perkebunan karet rakyat oleh karena itu, brasanya agak rendah (yang kadang-kadang berbeda berbalikan dengan harga pasar). Hal ini menggambarkan ketidak-bergantungan petani karet pada pengaruh-pengaruh ekonomi dan politik dari luar, dan ini merupakan kunci sukses mereka. Hal-hal khususyang menguntungkan dari sistem terpadu inipatut mendapatkanperhatian yang lebih besar dari perencana-perencana pembangunan.     

Saving face: the emotional costs of the Asian immigrant family myth

Access to resources through ethnic group membership is often presumed to affect the intensity of ethnic identification. We examine this premise using survey data on three ethnic groups in Mauritius: Creoles, Hindus, and Muslims. Two key findings emerge from our research. First, access to material resources explains only a modest proportion of total variation in ethnic identification within each group. Second, the resources that affect ethnic identification differ significantly across groups. Access to political goods through group membership affects Hindu identification but is unrelated to ethnic identification among Creoles or Muslims. Conversely, access to economic goods affects Creole and Muslim identification but has no effect on Hindu identification. Explaining these group differences leads us beyond a basic means–ends instrumentalist model to identify conditions that likely mediate the relationship between individual interests and collective identification including the divisibility of economic goods relative to political goods in Mauritius.     

藏羚的分布与迁移

2003年7月至8月调查了藏羚的分布区及其生活习性,并对藏羚的迁移活动进行了总结。提出雌藏羚的迁移是以昆仑山为中心,分布在昆仑山南面的雌藏羚夏季至秋初在北方产仔,其它季节在南方交配栖息,因此两地间存在往返迁移。分布在昆仑山北面的雌藏羚的迁移活动正好与之相反。同时,讨论了人类活动对藏羚栖息造成的影响,认为遏制“沙图什”的消费,禁止藏羚分布区的一切人类活动是保护藏羚的有效措施。     

Land cover change or land‐use intensification: simulating land system change with a global‐scale land change model

Land‐use change is both a cause and consequence of many biophysical and socioeconomic changes. The CLUMondo model provides an innovative approach for global land‐use change modeling to support integrated assessments. Demands for goods and services are, in the model, supplied by a variety of land systems that are characterized by their land cover mosaic, the agricultural management intensity, and livestock. Land system changes are simulated by the model, driven by regional demand for goods and influenced by local factors that either constrain or promote land system conversion. A characteristic of the new model is the endogenous simulation of intensification of agricultural management versus expansion of arable land, and urban versus rural settlements expansion based on land availability in the neighborhood of the location. Model results for the OECD Environmental Outlook scenario show that allocation of increased agricultural production by either management intensification or area expansion varies both among and within world regions, providing useful insight into the land sparing versus land sharing debate. The land system approach allows the inclusion of different types of demand for goods and services from the land system as a driving factor of land system change. Simulation results are compared to observed changes over the 1970–2000 period and projections of other global and regional land change models.     

Environmental Impacts of Capital Formation

The investment in capital goods is a well‐known driver of economic activity, associated resource use, and environmental impact. In national accounting, gross fixed capital formation (GFCF) constitutes a substantial share of the total final demand of goods and services, both in terms of monetary turnover and embodied resources. In this article, we study the structure of GFCF and the environmental impacts associated with it on a global scale, and link it to measures of development. We find that the share of GFCF as part of the total carbon footprint (CF) varies more across countries than GFCF as a share of gross domestic product (GDP). Countries in early phases of development generally tend to invest in resource‐intensive assets, primarily infrastructure and machinery, whereas wealthier countries invest in less resource‐intensive assets, such as computers, software, and services. By performing a structural decomposition analysis, we assess the relative importance of investment structure and input‐output multipliers for the difference in carbon intensity of capital assets, and find that the structure of investments plays a larger role for less‐developed countries than for developed countries. We find a relative decoupling of the CF of GFCF from GDP, but we can neither confirm nor rule out the possibility of an absolute decoupling.     

The Limits of Authenticity in Vietnamese Consumer Markets

In this article, I address the saliency of the concept of "authenticity" in contexts of international law and anthropological inquiry. Using my research findings in Ho Chi Minh City (HCMC), Vietnam, I show that although Vietnamese shoppers distinguish between what they term real and fake goods, they do not share with foreign corporations and international trade organizations a preoccupation with product and brand authenticity. To make this point, I describe four types of goods—model goods, mimic goods, real goods, and fake goods—employed by shoppers in HCMC, and discuss why they have little in common with notions of "authenticity" and "ownership" inherent in international standards of intellectual property. I argue that these conceptual differences in the commercial sphere challenge claims about the universal applicability of intellectual property rights laws and also encourage anthropologists to ask whether authenticity is always a useful tool of cross-cultural understanding.