Development of the concept of spatial–temporal mask for testing effects of discharge from well-drilling activities on biological communities

This paper describes the use of Bayesian spatial models to develop the concept of a spatial–temporal mask for the purpose of identifying regions in which before and after drilling effects are most clearly defined and from which the consequences of exposure of macrofauna and meiofauna to the release of drilling discharges can be evaluated over time. To determine the effects of drilling fluids and drill-cuttings on the marine benthic community, it is essential to know not only where discharged materials ended up within the possible impact area, but also the chemical concentrations to which biota were exposed during and after drilling. Barium and light hydrocarbons were used as chemical tracers for water-based and non-aqueous-based fluids in a shallow water site in the Campos Basin, off the coast of Brazil. Since the site showed evidence of exposure to waste material from earlier drilling, the analysis needed to take into account the background concentrations of these compounds. Using the Bayesian models, concentrations at unsampled sites were predicted and regions altered and previously contaminated were identified.     

Carbon Monoxide and Lead-An Environmental Appraisal

Because of the common source, lead and CO values in the atmosphere tend to behave in a similar manner. Thus, diurnal variations in these two pollutants show a pattern related to motor vehicle traffic flow. Also, the exposure to both vary by orders of magnitude with the highest being on the road (in the car) thus setting up special dosage situations. Community sources seem to affect background level at least based on fall-off with distance. There may be a relatively wider exposure of the general population to lead and CO. While the lead levels may not be increasing in the downtown portion of the central city proper, typical central city levels of several years ago may be more diffuse and spread out, thus occurring over increasingly large portions of the community. Similarly, there may be a wider exposure of the population to CO as the levels become more nearly uniformly high over a larger area. In addition, there may be problems of a shorter term exposure to high levels of CO in commuter traffic. This may be of consequence to selected types of drivers or passengers. Finally, it should also be noted that during air pollution episodes, CO levels appear to rise with no data currently available on changes in concomitant ambient lead levels.     

Measuring sustainability

An agricultural system is sustainable if productive output is maintained economically over time when assessed in relation to environmental concern. This paper considers ways of statistically evaluating measures of sustainability illustrated by reference to extensive data from the Classical Experiments at Rothamsted.     

2,3,7,8,-四氯苯噁英对NIH小鼠早期妊娠和生殖激素的影响

用不同剂量的2,3,7,8 四氯苯二英(2,3,7,8 tetrachlorodibenzopdioxin,TCDD)对小鼠胚胎附植数量和生长发育情况进行剂量反应评估,分析TCDD对假孕小鼠子宫蜕膜生长状况的影响以及比较胚胎种植前后染毒效果.所有样本采集血液,测定母体血清雌二醇和孕酮的浓度变化.结果表明,50和100ng·(kg·d)-1TCDD处理的孕鼠,胚胎附植数量明显减少(P<0 05),着床后胚胎出现发育迟缓,质量减轻(P<0 05);同等剂量TCDD处理的假孕小鼠,子宫蜕膜生长受到了极显著的抑制(P<0 01);种植前后染毒效果比较发现种植前期染毒的小鼠胚胎对TCDD更为敏感.母体血清雌二醇浓度随剂量和染毒时段有不同程度的升高,而孕酮浓度则极显著下降(P<0 01).由此表明低剂量TCDD可能通过对生殖激素的干扰,强烈影响NIH小鼠妊娠早期生殖生理状态和着床后胚胎的发育.实验同时证明小鼠也可作为早期妊娠毒物研究的供试动物,用以筛选动物和人类早期妊娠的有害化合物.     

Predictors of willingness to relocate for managerial and professional employees

This study explored possible determinants, both inside and outside the job sphere, of willingness to relocate. Data were collected from a large sample of managerial and professional employees in one organization. Unlike previous research, this study investigated willingness to relocate for three different purposes: (1) for a better job or career development; (2) to help the organization; or (3) to remain employed. However, only two factors of willingness to relocate emerged: willingness to relocate for career enhancement or company needs, and willingness to relocate to remain employed. Results showed that the strongest predictors of willingness to relocate to remain employed were job sphere variables such as satisfaction with career development opportunities and propensity to remain, while family and community variables were much more important in predicting willingness to relocate for career enhancement or company needs. The implications of these results for both the organization and individuals are discussed.     

use of 1970 census of population data for air pollution research

Today, many more communities in the United States are in a better position to undertake the study of the possible health effects of the air pollution in their environment than has been possible before. Further, such study may furnish baseline data for evaluating the efficacy of air pollution control activity in those cities.

Assessment by city and county control officials can be accomplished by examining the relationship between the demographic characteristics of the area as reported in the 1970 Census of Population, the aerometric measurements now being made routinely in many areas, and mortality in the population as reported to the state office of vital statistics. From the census, detailed demographic or population data will be available by census tract in urban areas. These areas include virtually every U. S. city with a population of 50,000 or more.

The procedures used in the Buffalo and Nashville Air Pollution Studies are discussed with a view toward possible replication by other geographic areas. The need to take account of differences in socio-economic status is emphasized, as is the desirability of obtaining smoking histories. Another major type of air pollution research which is again made possible by the 1970 Census is the comparison of mortality experience, on an agespecific and an age-adjusted basis centered around 1970, for the more than 200 Standard Metropolitan Statistical Areas in the United States.