Adult-onset GM2 gangliosidosis diagnosed in a fetus

Amniocentesis and subsequent tests are reported on a fetus conceived of a rare mating type: its mother has an intermediate level of β hexosaminidase A (HEX A), characteristic of carriers of Tay-Sachs disease (TSD), while the father suffers from an adult-onset GM₂ ganglio-sidosis (AOG) with severe HEX A deficiency. Activity of HEX A in the cultured fetal cells was very low when measured by the heat-inactivation method, thus showing the typical biochemical phenotype of TSD fetuses. However, upon separation of HEX isozymes by ion exchange chromatography, residual HEX A (17 per cent of total HEX) was demonstrated. Also in contrast to TSD fetuses, this fetus' fibroblasts were able to synthesize the precursor of a chains of HEX, and ultrastructural examination of its brain revealed few atypical lamellar bodies, unlike those found in TSD fetuses of the same gestational age. It is therefore concluded that the fetus was not affected with TSD, but rather with AOG.     

Determination and characterization of chloroguaiacol conjugates in fish bile by HPLC

In this study a small-scale technique for direct analysis of metabolic conjugates of 4,5,6-trichloro- (CG-3) and tetrachloroguaiacols (CG-4) in fish bile by RP-HPLC is presented. Only one metabolite, glucuronic acid conjugate, was demonstrated in two Lake Baikal fishes (Leuciscus leuciscus baikalensis and Cottus kessleri) exposed to CG-3 or CG-4 at 6 degrees C for 1-2 days. In Leuciscus the ratio between free CG-4 in the ambient water and conjugated CG-4 in the bile averaged 264,000. Intraperitoneal injections of tetrachloroveratrol (CV-4) into Thymallus arcticus baikalensis did not reveal any traces of free CV-4 or CG-4 glucuronide in the bile in 2 days at 5 degrees C. We therefore suggest that CV-4 was not demethylated and subsequently conjugated with glucuronic acid in the liver of this fish species.     

耕地质量监测中合理样本量配置及不确定性分析——以陕西省宝鸡市为例

耕地质量监测样本量的优化配置对降低成本,实现可持续土地资源监测与利用有重要指导价值。以陕西省宝鸡市为例,采用2018年耕地质量监测数据,运用传统统计学和地统计学方法,探讨耕地质量监测中土壤监测指标的合理样本量及不确定性。研究表明：样本变异性大小与样本量的关系并不是绝对的。样本代表性评价方法和地统计学方法较Cochran方法能有效降低样本的不确定性;样本代表性评价法适用性更广,但研究结果缺乏稳定性;地统计学方法的适用性存在局限性,可降低中等变异性指标的不确定性,但对低、高变异性指标适用性较低。中等变异性指标宜采用地统计学方法确定合理样本量;低、高变异性指标宜采用代表性评价方法确定合理样本量。     

Globalization and workplace hazards in developing nations

Multinational corporations are rapidly introducing hazardous technological activities into less-developed nations. There is considerable evidence that this feature of global commerce poses risks to health, safety and natural resources, and most immediately endangers the workers involved. The less-developed nations hosting these activities are vulnerable to exploitation of their human resources because they lack the safeguards, expertise, and public pressures that prevent harms to workers in developed nations. This paper presents an evaluation of approaches taken by international and industrial organizations to address workplace hazards by soft law, hard law, codes of conduct, and voluntary self-regulation. Finding that these approaches have repeatedly failed, a new approach is presented for the purpose of assuring that the transfer of technology will be accompanied by the transference of practices for using it safely. The key features of this approach are then considered: defining a standard of care which aims to provide equivalent treatment of worker health and safety across all nations, irrespective of their level of development, and establishing contractual relationships between multinational companies and host countries as a feasible means of implementing the standard and achieving equivalent treatment.     

Biotechnological research on the most dangerous pathogens: Challenges for risk governance and safety management

Biotechnological research on the deadliest pathogens has rapidly grown into a vast enterprise in the United States. With over $50 billion from federal agencies, thousands of projects are conducted at hundreds of university laboratories and other facilities in a national effort to gain the knowledge and methods for preventing the natural occurrence of pathogenic disease and protecting against bioterrorism. This paper describes this enterprise, defines several risk scenarios unrelated to terrorism which threaten lab workers and the public with lethal and contagious pathogenic disease, and evaluates the official policy framework for decision-making with regard to preventing and responding to the risk scenarios. It finds that the framework emphasizes physical security and secrecy to prevent terrorist exploitation of the enterprise, but fails to sufficiently address prevention of lab mishaps, accidental releases, and other incidents during the routine conduct of research which would expose workers and the public to the lethal pathogens. Nor does the framework effectively provide for the emergency response measures needed to prevent an accidental release of the more highly contagious pathogens from spiraling into a local or larger scale disease epidemic. These findings, supported by the growing number of near misses and small-scale incidents and lawsuits, point to major weaknesses in federal oversight and regulation, official disregard for siting criteria, inadequate self-regulation and management of lab safety practices, breakdowns in reporting systems, and obstacles to organizational learning and emergency response created by secrecy and security policies. Recommendations are made regarding these inadequacies of the federal framework and urge application of lessons learned from safety science experience with other hazardous technologies where increasing attention is being given to safety culture initiatives.