Abstract Objective Higher levels of exposure to extremely low-frequency magnetic fields （ELF-MF） are associated with a slightly increased risk of childhood leukaemia. Compared with more-developed Western countries, ...Abstract Objective Higher levels of exposure to extremely low-frequency magnetic fields （ELF-MF） are associated with a slightly increased risk of childhood leukaemia. Compared with more-developed Western countries, higher exposure levels are evident in the Czech Republic, probably because of the different types of housing. In light of this, we aimed to examine the association between ELF-MF exposure and childhood leukaemia in the Czech Republic. Methods We conducted a paired case-control study. The cases （children with leukaemia） were age- sex- and permanent residence-matched to controls （children without leukaemia）. Although this limited potential bias and confounding, it also limited our number of participants. Results The matched analyses included 79 case-control pairs. No significant association between ELF-MF exposure and childhood leukaemia was observed for exposures over 0.2 μT （odds ratio [0R]=0.93, confidence interval [Cl]=0.45-1.93）, 0.3 μT （0R=0.77, Cl=0.34-1.75）, or 0.4 μT （OR=0.9, Cl=0.37-2.22）. Conclusion Despite higher levels of exposure in Middle and Eastern Europe, no indication of an association between ELF-MF exposure and childhood leukaemia was determined. This in contrast to the findings of previous studies conducted in different countries.展开更多
Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were d...Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.展开更多
Vector surveillance is very key in solving mosquito-borne health problems in Nigeria.To this end,the composition and distribution of mosquito vectors in a peri-urban community surrounding an institution of learning in...Vector surveillance is very key in solving mosquito-borne health problems in Nigeria.To this end,the composition and distribution of mosquito vectors in a peri-urban community surrounding an institution of learning in Lafia metropolis,Nasarawa State,Central Nigeria was carried out between December 2016 and June 2017.The Prokopack Aspirator was used to collect indoor resting mosquitoes between 6:00 a.m.and 9:00 a.m.from 30 randomly selected houses.Mosquitoes collected were knocked down and transferred into a well labelled petri-dish and taken to the laboratory for processing.A total of 664 mosquitoes were collected which spread across Culex quinquefasciatus 572(86.14%),Anopheles gambiae 88(13.25%)and Aedes aegypti 4(0.60%).The abundance of mosquitoes in relation to seasons,species,sex,abdominal conditions as well as transmission indices across seasons significantly varied(P<0.05).But,the distribution of mosquito in relation to house types showed no significant difference(P>0.05).The inhabitants of the area should ensure that all drainages flow through so as to reduce mosquito breeding grounds.Also,members of the community should always protect themselves by sleeping under insecticide treated bed nets.展开更多
文摘Abstract Objective Higher levels of exposure to extremely low-frequency magnetic fields （ELF-MF） are associated with a slightly increased risk of childhood leukaemia. Compared with more-developed Western countries, higher exposure levels are evident in the Czech Republic, probably because of the different types of housing. In light of this, we aimed to examine the association between ELF-MF exposure and childhood leukaemia in the Czech Republic. Methods We conducted a paired case-control study. The cases （children with leukaemia） were age- sex- and permanent residence-matched to controls （children without leukaemia）. Although this limited potential bias and confounding, it also limited our number of participants. Results The matched analyses included 79 case-control pairs. No significant association between ELF-MF exposure and childhood leukaemia was observed for exposures over 0.2 μT （odds ratio [0R]=0.93, confidence interval [Cl]=0.45-1.93）, 0.3 μT （0R=0.77, Cl=0.34-1.75）, or 0.4 μT （OR=0.9, Cl=0.37-2.22）. Conclusion Despite higher levels of exposure in Middle and Eastern Europe, no indication of an association between ELF-MF exposure and childhood leukaemia was determined. This in contrast to the findings of previous studies conducted in different countries.
文摘Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.
文摘Vector surveillance is very key in solving mosquito-borne health problems in Nigeria.To this end,the composition and distribution of mosquito vectors in a peri-urban community surrounding an institution of learning in Lafia metropolis,Nasarawa State,Central Nigeria was carried out between December 2016 and June 2017.The Prokopack Aspirator was used to collect indoor resting mosquitoes between 6:00 a.m.and 9:00 a.m.from 30 randomly selected houses.Mosquitoes collected were knocked down and transferred into a well labelled petri-dish and taken to the laboratory for processing.A total of 664 mosquitoes were collected which spread across Culex quinquefasciatus 572(86.14%),Anopheles gambiae 88(13.25%)and Aedes aegypti 4(0.60%).The abundance of mosquitoes in relation to seasons,species,sex,abdominal conditions as well as transmission indices across seasons significantly varied(P<0.05).But,the distribution of mosquito in relation to house types showed no significant difference(P>0.05).The inhabitants of the area should ensure that all drainages flow through so as to reduce mosquito breeding grounds.Also,members of the community should always protect themselves by sleeping under insecticide treated bed nets.
