首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
《Fire Technology》1989,25(2):188-190

Current Research Activities

U.S. Center for Fire Research highlights  相似文献   

2.

Current Research

Comparative study on the performance of the U.S. standard spray sprinkler and the european conventional style sprinkler  相似文献   

3.
Background levels of polychlorinated biphenyls in the U.S. population   总被引:1,自引:0,他引:1  

Background

Polychlorinated biphenyl (PCB) exposures are encountered by the general public by eating contaminated food or living near a previously operating PCB factory or hazardous waste site. PCBs affect the immune, reproductive, nervous, and endocrine systems and are carcinogens. PCBs were banned in the United States in 1977. For public health, it is important to be able to estimate individual risk, especially for vulnerable populations, to monitor the decline in risk over time and to alert the public health community if spikes occur in PCB exposures, by measuring serum PCB levels. The historical decline in PCB exposures cannot be documented within a repeatedly tested general population, since there is no such population. Therefore, our aim was to model serum PCB levels in the US general population over time using published data.

Methods

Models were developed based on 45 publications providing 16,914 background PCB levels in sera collected 1963-2003. Multiple linear regression and exponential decay were used to model the summary PCB levels.

Results

Background levels of higher-chlorinated PCBs (five or more chlorines) in sera increased before 1979 and decreased after 1979; a quadratic model was the best fit. However, the exponential decay model explained better the low PCB serum levels still seen in the general population. For lower-chlorinated serum PCBs, no increase or decrease was shown (1.7 ppb for all years).

Conclusions

Limitations for both models were lack of repeated measures, non-randomly selected study participants, selected years, concentration on geographic areas centered on PCB waste sites, lack of adjustment for BMI or for laboratory methods. Despite the limitations, this analysis shows that background PCB levels in the general population are still of concern. Future work should focus on uncertainties governing how to interpret the levels with respect to possible long term health effects.  相似文献   

4.

Background

A number of studies have examined the relationship between high ambient temperature and mortality. Recently, concern has arisen about whether this relationship is modified by socio-demographic factors. However, data for this type of study is relatively scarce in subtropical/tropical regions where people are well accustomed to warm temperatures.

Objective

To investigate whether the relationship between daily mean temperature and daily all-cause mortality is modified by age, gender and socio-economic status (SES) in Brisbane, Australia.

Methods

We obtained daily mean temperature and all-cause mortality data for Brisbane, Australia during 1996-2004. A generalised additive model was fitted to assess the percentage increase in all deaths with every one degree increment above the threshold temperature. Different age, gender and SES groups were included in the model as categorical variables and their modification effects were estimated separately.

Results

A total of 53,316 non-external deaths were included during the study period. There was a clear increasing trend in the harmful effect of high temperature on mortality with age. The effect estimate among women was more than 20 times that among men. We did not find an SES effect on the percent increase associated with temperature.

Conclusions

The effects of high temperature on all deaths were modified by age and gender but not by SES in Brisbane, Australia.  相似文献   

5.

Background

Risks from electromagnetic devices are of considerable concern. Electrohypersensitive (EHS) persons attribute a variety of rather unspecific symptoms to the exposure to electromagnetic fields. The pathophysiology of EHS is unknown and therapy remains a challenge.

Objectives

Heavy metal load has been discussed as a potential factor in the symptomatology of EHS patients. The main objective of the study was to test the hypothesis of a link between EHS and heavy metal exposure.

Methods

We measured lead, mercury and cadmium concentrations in the blood of 132 patients (n = 42 males and n = 90 females) and 101 controls (n = 34 males and n = 67 females).

Results

Our results show that heavy metal load is of no concern in most cases of EHS but might play a role in exceptional cases.

Conclusions

The data do not support the general advice to heavy metal detoxification in EHS.  相似文献   

6.
Rechtsprechung     

Rechtsprechung

Rechtsprechung  相似文献   

7.
Multiphysics modeling of building physical constructions   总被引:1,自引:0,他引:1  

Editorial

Editorial  相似文献   

8.

Rechtsprechung

?ffentliches Recht  相似文献   

9.
New Publications     

Advertisement

New Publications  相似文献   

10.
11.

Instructions for Authors

Instructions for Authors  相似文献   

12.

Authors Index

Author Index Volume 17  相似文献   

13.

Volume Contents

Contents of Volume 15  相似文献   

14.

Ausbildung und Beruf

Ausbildung und Beruf  相似文献   

15.
Neues Baurecht     

Neues Baurecht

Neues Baurecht  相似文献   

16.
Neues Baurecht     

Neues Baurecht

Neues Baurecht  相似文献   

17.
1999 Index     

Subject Index

1999 Index  相似文献   

18.

Buchbesprechungen

Buchbesprechungen  相似文献   

19.
Rechtsprechung     

Rechtsprechung

Rechtsprechung  相似文献   

20.
《Fire Technology》1988,24(3):271-272

Current Research Activities

Flammable liquid container storage  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号