Effect of risk aversion on prioritizing conservation projects

Conservation outcomes are uncertain. Agencies making decisions about what threat mitigation actions to take to save which species frequently face the dilemma of whether to invest in actions with high probability of success and guaranteed benefits or to choose projects with a greater risk of failure that might provide higher benefits if they succeed. The answer to this dilemma lies in the decision maker's aversion to risk—their unwillingness to accept uncertain outcomes. Little guidance exists on how risk preferences affect conservation investment priorities. Using a prioritization approach based on cost effectiveness, we compared 2 approaches: a conservative probability threshold approach that excludes investment in projects with a risk of management failure greater than a fixed level, and a variance‐discounting heuristic used in economics that explicitly accounts for risk tolerance and the probabilities of management success and failure. We applied both approaches to prioritizing projects for 700 of New Zealand's threatened species across 8303 management actions. Both decision makers’ risk tolerance and our choice of approach to dealing with risk preferences drove the prioritization solution (i.e., the species selected for management). Use of a probability threshold minimized uncertainty, but more expensive projects were selected than with variance discounting, which maximized expected benefits by selecting the management of species with higher extinction risk and higher conservation value. Explicitly incorporating risk preferences within the decision making process reduced the number of species expected to be safe from extinction because lower risk tolerance resulted in more species being excluded from management, but the approach allowed decision makers to choose a level of acceptable risk that fit with their ability to accommodate failure. We argue for transparency in risk tolerance and recommend that decision makers accept risk in an adaptive management framework to maximize benefits and avoid potential extinctions due to inefficient allocation of limited resources. El Efecto de la Aversión de Riesgo sobre la Priorización de Proyectos de Conservación     

Risk analysis for road and rail transport of hazardous materials: a GIS approach

An approach to transportation risk analysis for road and rail transport of dangerous goods is proposed, which is based on the use of geographic information systems (GIS) to manage territorial information, coupled with a product data bank in a risk evaluation tool. Such an approach enables to accurately take into account the local data affecting risk analysis, such as population, accident rate, and weather conditions along all the route, by means of a system which can be easily updated. The resulting risk evaluation tool assists in the step of route identification and allows to rapidly perform an accurate transportation risk analysis, for a single transportation event as well as for multiple substances, trips and itineraries.     

污水污泥制油技术研究进展

目前污水污泥传统处理方法存在一定的不足和弊端,污泥制油技术不断得到了研究者的关注。对污泥制油技术的发展进行综述,特别就工艺操作条件、催化剂的使用等方面介绍了污泥低温热解技术,并对污泥制油技术提出几点展望。     

吡虫啉的生物效应研究

应用不同的生物材料对新型杀虫剂的生态效应进行了研究，吡虫啉对泽蛙蝌蚪，黑斑蛙蝌蚪及青Jiang鱼的急性毒性表明，吡虫啉属于低毒农药，蚕豆根尖微核试验结果呈阴性，揭示其无致突变效应。     

浅谈保护生态环境和资源的永续利用与可持续发展

我们必须重视生态资源的保护以确保经济和社会的可持续发展     

黄鳝染色体体外SCE检测系统的建立及对两种清洗剂的检测

姐妹染色单体交换(SCE)技术已在细胞生物学、细胞遗传学、环境毒理学、医学等领域得到了重视和应用。在检测环境诱变剂和致癌剂方面,SCE比染色体畸变敏感二百倍。 关于体外SCE检测系统的研究,除了较多地利用人外周血淋巴细胞和中国仓鼠卵巢(CHO)细胞作为SCE检测材料外,也开始利用各种生态环境中的动物。对鱼类SCE的研究,国外做过一些工作,但有关建立SCE检测系统的报道极少。国内有关     

Problems in prenatal diagnosis of β-thalassaemia by fetal blood analysis: β-chain variant comigrating with gamma chains

This report describes a couple at risk for β thalassaemia in which one spouse was heterozygous for classical high Hb A2 β-thalassaemia while the other had the compound heterozygous state for β⁺-thalassaemia and a β-chain variant. This variant comigrates on carboxymethyl-cellulose columns (CMC) with γ-chains, indicating that globin separation on CMC columns could not have been used for fetal diagnosis. The β-chain variant migrates separately from the other globin chains on HPLC and the respective abnormal haemoglobin can be separated by isoelectrofocusing. Oligonucleotide hybridization showed that both parents were carriers of the β⁺ IVS-1, nt 6 mutation. Prenatal diagnosis was successfully accomplished by oligo-nucleotide analysis on trophoblast DNA. This case indicates that an Antenatal Service should have alternative methods to CMC columns so as to carry out prenatal diagnosis of β-thalassaemia in uncommon cases.     

Prenatal diagnosis of hunter syndrome using chorionic villi

A case of the Hunter syndrome diagnosed prenatally using chorionic villi is presented. Chorion biopsy was performed in the 10th week of pregnancy. The sample was examined for karyotype and for iduronate sulfatase activity. The fetus was male and the enzyme activity reduced to 4 per cent of normal. Termination of pregnancy occurred at the 11th week.     

First trimester diagnosis of β-thalassaemia in a twin pregnancy

This paper reports the results of first trimester prenatal diagnosis in a twin pregnancy at risk for homozygous β°−thalassaemia (β°−39 mutant). Trophoblast samples from both twins were obtained at 10 weeks gestation with a forceps guided by ultrasound. Trophoblast DNA analysis, carried out with the oligonucleotide technique, revealed that one fetus was homozygous and the other heterozygous for the β−39 mutant. This diagnosis was confirmed at 17 weeks gestation by amniocyte DNA analysis. DNA polymorphism analysis within the α-globin gene provided useful genetic markers for twin differentiation.