Incentive compatibility tests of choice experiment value elicitation questions

This paper uses laboratory experiments with induced values to address fundamental issues related to the incentive compatibility of choice experiment value elicitation questions. In particular, we compare two- versus three-option choice sets and the effect of using alternative provision rules, including one where the outcome is influenced by both participant and “regulator” votes. We find the overall proportion of choices that are inconsistent with induced preferences is rather low. However, there are more deviations from induced preferences for two-option choice sets, and for alternatives to a simple plurality vote implementation rule. A multinomial probit analysis of choices in tandem with a mixed logit welfare analysis suggests there is a statistically significant but modest degree of bias towards selecting the status quo option.     

The Role of Incentive Programs in Conserving the Snow Leopard

Abstract:   Pastoralists and their livestock share much of the habitat of the snow leopard ( Uncia uncia ) across south and central Asia. The levels of livestock predation by the snow leopard and other carnivores are high, and retaliatory killing by the herders is a direct threat to carnivore populations. Depletion of wild prey by poaching and competition from livestock also poses an indirect threat to the region's carnivores. Conservationists working in these underdeveloped areas that face serious economic damage from livestock losses have turned to incentive programs to motivate local communities to protect carnivores. We describe a pilot incentive program in India that aims to offset losses due to livestock predation and to enhance wild prey density by creating livestock-free areas on common land. We also describe how income generation from handicrafts in Mongolia is helping curtail poaching and retaliatory killing of snow leopards. However, initiatives to offset the costs of living with carnivores and to make conservation beneficial to affected people have thus far been small, isolated, and heavily subsidized. Making these initiatives more comprehensive, expanding their coverage, and internalizing their costs are future challenges for the conservation of large carnivores such as the snow leopard.     

人力资本效能的彰显:激励与约束

人力资本是生产要素中最活跃和最特殊的要素，它的激励与约束问题极为精巧、复杂．本文通过对人力资本激励与约束问题的考察，结合我国体制内企业运营的实践，初步探讨了人力资本激励与约束的机制．     

超细粉尘的扬尘机理研究

针对目前对于一般尘源控制研究较少,而系统研究粉尘的扬尘(尘化)机理的研究就更少这一状况,提出弄清尘化机理、从源头上控制是治理粉尘的首要问题,对粉尘颗粒作用力进行分析,特别就超细粉尘的扬尘机理提出相应的物理模型并进行初步研究.图1,参2.     

Mechanisms of arsenic removal from water

In this review paper, various methods for arsenic removal from water have been described by explaining the related mechanisms of each methods. Advantages and drawbacks were discussed. Membrane methods were suggested as reliable methods for elimination of arsenic from water in addition to other conventional separation methods.     

Financial Mechanisms for Conservation in Brazil

Abstract:  I reviewed some of the financial mechanisms for biodiversity conservation activities in Brazil. There is a heavy dependence on the public sector, but macroeconomic policies aimed at reducing government spending have resulted in reduced budgets dedicated to public conservation measures. The financial constraints for environmental protection have also increased because of a reduction in foreign aid. Positive signs for the immediate future, however, come from new initiatives that create economic instruments to finance conservation. The most important initiatives include conservation criteria for tax redistribution; environmental compensation; water charges; royalties for electricity, petroleum, and natural gas; tradable obligations for forest reserves; and voluntary measures on the part of the business sector. Resources created from these initiatives have different origins and are managed by different public agencies according to varying laws and policies, so their efficient implementation will require that the institutions involved in biodiversity conservation in Brazil establish a minimum set of common priorities and objectives.     

Incentive Structure of and Private Landowner Participation in an Endangered Species Conservation Program

Abstract: In the United States, voluntary incentive programs that aid conservation of plant and wildlife species on private lands provide a structural solution to the problem of protecting endangered species by reducing costs and enhancing benefits to landowners. We explored the potential for incentives to encourage landowners to manage land cover for the benefit of endangered songbirds in central Texas (U.S.A.) by asking landowners to indicate their preferences for financial incentives, technical assistance, and regulatory assurances. We identified owners of potential songbird habitat and collected data in face‐to‐face interviews and self‐administered questionnaires. We used a latent‐class stated‐choice model to identify 3 classes of landowners whose choices varied on the basis of their attitudes and perceived social norms: (1) strong positive attitude, perceived social pressure to participate, and willing to participate with relatively few incentives, (2) weak positive attitude, perceived no social pressure to participate, and required strongest incentives, and (3) negative attitude, perceived social pressure not to enroll, and unwilling to participate regardless of incentive structure. Given this heterogeneity in preferences, conservation incentives may increase management of land cover to benefit endangered species on private lands to some degree; however, exclusive reliance on incentives may be insufficient. Promoting conservation on private lands may be enhanced by integrating incentives into an approach that incorporates other strategies for conservation, including social networks and collaborative processes that reinforce social norms.     

Mechanisms in sensitized photochemistry of environmental chemicals

This review consists of three main parts. After a short discussion of the theory of photochemistry, the three major mechanisms (radiative, short range and long range) for the transfer of electronic excitation energy from sensitizers (donors) to substrates (acceptors) are described. Criteria for the selection of. sensitizers are a high efficiency of intersystem crossing (in the case of triplet sensitization) and energy transfer, and strong absorption at wavelengths longer than those at which the acceptor absorbs. Two mechanisms of sensitized photo‐oxygenation, viz. the radical and singlet oxygen type, are discussed.

The second part of this review deals with photosensitizers, with a strong emphasis on compounds of importance in environmental photochemistry on the one hand and those interesting from a mechanistic point of view on the other.

The third part describes photo‐inducers and their role in photoreactions.

Additional literature references (to January 1978) are presented at the end of this review.     

Mechanisms enabling sperm economy in blenniid fishes

Sperm competition, cost of spermatogenesis and spawning frequency are known to influence ejaculate expenditure. Accordingly, males, particularly those with high reproductive costs, are expected to have evolved mechanisms enabling them to prudently allocate sperm, such as the fractioning of ejaculate expenditure or the semi-cystic type of spermatogenesis, hypothesised to favour the production of small ejaculates. In this study, we investigate sperm competition risk, ejaculate size and mode of ejaculate release in seven polygynous blenniid fish where males provide sole paternal care of eggs. In addition, we estimated the relative size of the two parts composing the male gonad, the strictly testicular (testicular lobules or testis) and the glandular (testicular gland), as the development of the latter is indicative of the level of semi-cystic spermatogenesis. In all the examined species, eggs were laid one by one, and the sperm expenditure at mating, evaluated as the total number of sperm released per mating, was parcelled out in several successive ejaculations, allowing males to adjust the release of sperm to the duration of egg deposition. In accordance with sperm competition theory, species experiencing higher sperm competition risk allocated more in sperm, both considering ejaculate size and ejaculate expenditure per mating. An increase in sperm expenditure was paralleled by the development of the testis at the expense of the testicular gland. Smaller species, whose males do not face sperm competition risk and fecundity is low, produced smaller ejaculates and exhibited a more developed testicular gland, supporting the hypothesis that a semi-cystic type of spermatogenesis is a mechanism allowing sperm economy.     

填埋场粘土衬里破坏机理分析

填埋场粘土衬里可能发生开裂、开孔、解体等形式的破坏。开裂的主要机理是干湿循环作用、物理化学作用及差异沉降作用。开孔的主要机理是管涌和穿透。边坡失稳和冻融循环可能使粘土衬里的连结结构解体。     

微生物砷还原机制的研究进展

砷是一种剧毒物质,环境中的砷对人体健康存在潜在威胁,因此长期以来备受关注.微生物的各种代谢过程对砷在环境中的归趋起着重要作用,其中砷还原微生物能将吸附于固体矿物中的As(Ⅴ)还原为可溶性强的As(Ⅲ),使砷进入液相,从而加剧了地下水等饮用水源的砷污染.论文主要介绍了两种微生物砷还原机制(异化砷还原和细胞质砷还原)在作用...     

植物铜素毒害及其抗性机制研究进展

Cu是植物生命活动必需的微量矿质元素，广泛参与各种生命活动；但过量Cu胁迫将诱导植物细胞产生大量活性氧，引起膜脂过氧化，膜透性增大，细胞内容物大量外渗，甚至发生细胞死亡。Cu^2 扩散到细胞核内会诱发DNA之间、蛋白质之间以及DNA和蛋白质之间发生分子内和分子间交联，DNA链的断裂、重排和脱嘌呤作用等前诱变损伤以及DNA期外合成、DNA甲基化异常等遗传毒害。植物细胞在长期进化过程中形成了各种抗Cu素毒害机制，如细胞壁的固着作用、质膜的限制作用、有机小分子(有机酸、植物螯合肽、金属硫蛋白)螯合作用等。文章综述了有关研究的最新进展。     

生物表面活性剂对铜绿假单胞菌摄取烷烃的强化机制

考察了2株铜绿假单胞菌(Pseudomonasaeruginosa)以正十六烷为底物生长的不同方式,并初步探讨了生物表面活性剂在烃类降解菌摄取烷烃过程中的作用机制.菌株O-2-2在正十六烷中的生长明显快于PS-1,生长过程中O-2-2分泌出鼠李糖脂生物表面活性剂,正十六烷被完全乳化.另外,O-2-2菌细胞表面疏水性高于PS-1,而加入鼠李糖脂使得菌体细胞中脂多糖含量减少,菌细胞表面疏水性明显提高.上述结果表明,鼠李糖脂主要通过乳化疏水性底物和提高降解菌表面疏水性两种机制强化铜绿假单胞菌(P.aeruginosa)对烷烃的摄取.图6表1参14     

外来植物入侵机制研究进展与展望

从植物入侵的内因、外因、驱动力和入侵过程等方面综述了植物入侵机制的研究进展:(1)外来植物由于预适应性较强或由于杂交和多倍体化而具有较强的侵染力:(2)外来植物由于逃脱原生区域的自然天敌,或由于土著种竞争较弱、生物多样性较低、植食动物或疾病较少等导致的生物抵抗力较低,或因良好的资源可获得性及入侵植物的化感作用等造成新栖息地可侵人性的增加;(3)自然或人为引入外来植物及对新栖息地的扰动是植物入侵的驱动力;(4)外来植物可能通过基于事件的入侵、入侵崩溃和协同入侵等人侵过程机制实现其成功入侵,分析了各入侵机制对入侵植物防控、生态学和进化学研究意义以及待解决问题.结果表明,植物入侵机制高度复杂,不同的外来植物种、新柄息地类型及植物入侵的不同阶段,各入侵机制可能单独或共同作用,为针对性地设计植物入侵防控方案提供了理论支撑.最后对植物入侵机制理论及其在植物入侵预测、危险性分区和防控中的应用研究等进行了展望.     

DINP的健康效应及机理研究进展

增塑剂邻苯二甲酸二异壬酯(di-isononyl phthalate,DINP)广泛应用于聚氯乙烯塑料消费品和工业产品中,因其对人体多个系统均有毒性作用,DINP的健康效应成为研究热点.笔者对近年来国内外的相关研究进行综述,对DINP的内分泌毒性、生殖发育毒性、心血管毒性、免疫毒性及神经毒性等多种毒作用及机理进行了系统...     

纳米材料对鼠科动物的生殖毒性及致毒机理

纳米材料是近几年应用越来越多的一种新型材料,因此国内外科研单位对其毒性的研究也逐年增加。但是目前对鼠科动物生殖毒性及其机理的了解还相对较少,亟需大量研究填补此领域的空白。本文主要从亲代和子代2个方面阐述了纳米材料对鼠科动物的生殖毒性,从不同生物水平等方面概述了纳米材料对亲子两代鼠科动物的损伤效应及可能的机制。最后,试探性地提出了今后在纳米材料领域对鼠科动物生殖毒性的研究重点。