Due to possible health effects of electric and magnetic fields, a directive on minimum health and safety requirements regarding the exposure of workers to electromagnetic fields has been disposed by European Parliamen...Due to possible health effects of electric and magnetic fields, a directive on minimum health and safety requirements regarding the exposure of workers to electromagnetic fields has been disposed by European Parliament and Council regarding the exposure of workers to electromagnetic fields. This legislation will be nationally implemented in 2012.The aim of this work was to develop a electromagnetic field exposure measurement method and further a magnetic field hazard evaluation method for exposure of workers in indoor medium to low voltage （MV/LV） distribution substations. Magnetic field exposure was also reflected with BS 8800 general risk classification procedure to accomplish specifications to execute magnetic field measurements and carry our risk assessment procedure for working tasks. The risk assessment procedure is based on magnetic field exposure measurements and dosimetric FEM calculations founded on EU Directive 2004/40/EC. According to field measurements action values were exceeded in several working tasks but limit values were not exceeded.展开更多
We collected data on sleeping site use from two groups of white-headed langurs Trachypithecus leucocephalus living in Fusui Nature Reserve, China between August 2007 and July 2008. This information was used to test se...We collected data on sleeping site use from two groups of white-headed langurs Trachypithecus leucocephalus living in Fusui Nature Reserve, China between August 2007 and July 2008. This information was used to test several hypotheses regarding ultimate causes of sleeping site use in this primate. White-headed langurs slept either in caves （17 sites） or on a cliffledge （one site）. They used all sleeping sites repeatedly, and reused some of them on consecutive nights; three nights was the longest consecutive use of any one sleep site. We suggest that langurs use sleeping sites to make approach and attack by predators difficult, and to increase their own familiarity with a location so as to improve chances for escape. Langurs＇ cryptic behaviors with an increased level of vigilance before entering sleeping sites may also help in decreasing the possibility of detection by predators. Group 1 spent more sleeping nights in the central area of their territory than expected; in contrast, group 2 spent more sleeping nights in the periphery of their territory, which overlaps with that of another groups, than expected. The position of sleeping site relative to the last feeding site of the day and the first feeding site of the subsequent morning indicated a strategy closer to that of a multiple central place forager than of a central place forager. These results suggest that territory defense and food access may play an important role in sleeping site use of white-headed langurs [Current Zoology 57 （3）： 260-268, 2011].展开更多
文摘Due to possible health effects of electric and magnetic fields, a directive on minimum health and safety requirements regarding the exposure of workers to electromagnetic fields has been disposed by European Parliament and Council regarding the exposure of workers to electromagnetic fields. This legislation will be nationally implemented in 2012.The aim of this work was to develop a electromagnetic field exposure measurement method and further a magnetic field hazard evaluation method for exposure of workers in indoor medium to low voltage （MV/LV） distribution substations. Magnetic field exposure was also reflected with BS 8800 general risk classification procedure to accomplish specifications to execute magnetic field measurements and carry our risk assessment procedure for working tasks. The risk assessment procedure is based on magnetic field exposure measurements and dosimetric FEM calculations founded on EU Directive 2004/40/EC. According to field measurements action values were exceeded in several working tasks but limit values were not exceeded.
基金supported by Research Funds of the National Nature Science Foundation of China （No, 30860050）, Guangxi Science Foundation （0991095）, Foundation of Key Laboratory of Southwest China Wildlife Resources Conservation （Ministry of Education）, China West Normal University, Protection and Assessment, Monitoring and Conservation of Langur Project of National Forestry Administration of China, and Guangxi Beibu Gulf Serious Specialisation of Guangxi Natural Sciences Foundation （No. 2010GXNSFE013004）. We thank the Guangxi Forestry Bureau, and Fusui Rare Animal Nature Reserve. We thank Dr. Ali Krzton for her assistance with language editing. We also ac- knowledge the critical comments of four anonymous reviewers.
文摘We collected data on sleeping site use from two groups of white-headed langurs Trachypithecus leucocephalus living in Fusui Nature Reserve, China between August 2007 and July 2008. This information was used to test several hypotheses regarding ultimate causes of sleeping site use in this primate. White-headed langurs slept either in caves （17 sites） or on a cliffledge （one site）. They used all sleeping sites repeatedly, and reused some of them on consecutive nights; three nights was the longest consecutive use of any one sleep site. We suggest that langurs use sleeping sites to make approach and attack by predators difficult, and to increase their own familiarity with a location so as to improve chances for escape. Langurs＇ cryptic behaviors with an increased level of vigilance before entering sleeping sites may also help in decreasing the possibility of detection by predators. Group 1 spent more sleeping nights in the central area of their territory than expected; in contrast, group 2 spent more sleeping nights in the periphery of their territory, which overlaps with that of another groups, than expected. The position of sleeping site relative to the last feeding site of the day and the first feeding site of the subsequent morning indicated a strategy closer to that of a multiple central place forager than of a central place forager. These results suggest that territory defense and food access may play an important role in sleeping site use of white-headed langurs [Current Zoology 57 （3）： 260-268, 2011].
