Influence of the Interaction of a 900 MHz Signal with Gender on EEG Energy: Experimental Study on the Influence of 900 MHz Radiation on EEG

Summary The effects of electromagnetic fields (EMF) emitted by cellular phones on human electroencephalogram (EEG) were studied during an auditory memory task. The experimental method and the experimental setup are introduced as a credible measurement method of EEG. 19 normal subjects (10 women and 9 men) performed the memory task both with and without exposure to a 900 MHz signal, emitted by a dipole antenna placed near the subjects' head. The energy of the EEG signals was calculated at the time domain. A Fourier transform of the EEG signals was done and the EEG energy was also calculated at the frequency domain. As the Parseval's theorem anticipates the energies were identical. The EEG energy was found concentrated at the four basic bands (α (8–13 Hz), β(14–30 Hz), δ (0–4 Hz) and θ(5–7 Hz)). The primary concern of the present study was the gender related influence of EMF on the spectral energy of EEG. The results show evidence of a strong gender—radiation interaction effect on the EEG energy and on the peak amplitudes within each of the four rhythms. Without radiation the spectral power of males is greater than of females, while under exposure the situation is reversed. Under the influence of EMF the spectral power of the males EEG is decreased while that of the females is increased. In conclusion both the baseline EEG and the changes effected to the EEG power spectrum under the influence of EMF seem to be gender dependent.     

拟合风频法计算重庆大气稳定度频率

本文用韦伯分布拟合风频,在确定大气稳定度的三因子太阳高度角、云量和风速是相互独立的变量的假定下,用计算单个变量频率的方法,计算了重庆5年的P—T大气稳定度频率,其结果与原P—T法统计结果十分吻合。对误差综合分析后给出了合理的订正方案,个例订正表明了方案的正确性。通过大量迭代推算给出重庆风速韦伯分布最佳函数值,以供选用。     

维生素C对除草剂诱发泥鳅红细胞微核率的影响

应用泥鳅外周血红细胞微核试验，研究了维生素Ｃ对３种除草剂诱发泥鳅遗传物质损伤的影响。结果表明，维生素Ｃ和除草剂共同作用时，均能显著降低除草剂诱发的外周血红细胞微核率，说明维生素Ｃ可以抑制除草剂对鱼类的遗传毒性作用。因此，在鱼饲料中添加适量的维生素Ｃ对鱼类具有保护作用。     

通过频谱分析了解冷却塔噪声污染特性

目前,冷却塔噪声评价所采用的指标是A声级。而由于A声级并不能全面的反应冷却塔噪声污染的特性。本文通过对冷却塔噪声污染案例进行频谱监测,探讨了频谱分析方法对评价冷却塔噪声污染特性的可行性。     

关于弹性地基上圆环形薄板振动问题的解答

对弹性地基上圆环形薄板的振动问题进行了分析和求解,给出了计算固有频率的计算公式和必要的数据,所考虑的边界条件是内外周边固支和内外周边简支两种情况,外径与内径的比值是2.5,3.0,3.5,4.0,4.5,5.0六种情况.     

Pericentric inversion of the Y chromosome and prenatal diagnosis

Pericentric inversion of the human Y chromosome has been estimated to occur with a frequency of 1–2 per thousand in various populations, and the results of this study, derived from over 12 000 prenatal diagnosis cases, is 1.15 per 1000. In these cases, it was concluded that there was no clinical significance because the fathers and male fetuses had the same pericentric inversion. Chromosome analysis of the father is advisable to determine whether or not the inversion is familial in order to be able to provide genetic counselling.     

油罐挥发气回收系统的模糊控制

介绍应用模糊控制器和变频调速器控制天然气压缩机自动回收油罐原油挥发气系统的控制原理．     

设备作业职业事故的预测分析及对策

目前,我国直接和间接参与设备作业的人数,达二亿多人。因此,职业作业安全十分重要。本文介绍了应用FFT谱分析技术进行职业作业事故预测分析,能在潜在性故障尚未转变成功能性故障前,即发生事故前给出预告,便于人们实施措施对策。从而从根本上杜绝事故的发生,确保生产安全。     

Strategic 3-hydroxy-2-butanone release in the dominant male lobster cockroach, <Emphasis Type="Italic">Nauphoeta cinerea</Emphasis>

In the lobster cockroach Nauphoete cinerea, the dominant–subordinate hierarchy formed via the agonistic interactions is unstable, and changes in rank order are common. Our previous results showed that in the first encounter fight during initial rank formation, microgram levels of 3H-2B are released by the aggressive posture (AP)-adopting dominant male. In the present study, the pattern of daily pheromone (3H-2B) release during the domination period and on the day of rank switch, rank duration, and rank switch frequency were investigated in three-male groups and six-male groups to examine the effect of higher frequency of agonistic encounters. The results showed that, in the three-male groups (50-day observation period), daily 3H-2B release rate was not constant, but fluctuated, the average duration of dominant rank was 16.6 ± 2.0 days, rank switch occurred in 58.8% of groups, and the frequency of rank switching (average number of rank switches/group/50 days) was 1.4 ± 0.2. For the six-male groups (30-day observation period), the daily 3H-2B release rate also fluctuated, but the duration of dominant rank was significantly shorter at 4.2 ± 0.6 days, rank switch occurred in 100% of groups, and the frequency of rank switching (average number of rank switches/group/30 days) was significantly higher at 6.9 ± 0.6. The results for both sets of male groups showed that as a new rank formed (either on the first encounter day or on the day of rank switching), the dominant status was significantly associated with a higher 3H-2B release rate. In the animal kingdom, fighting usually involves communication or the exchange of signals, and the results of this study indicated that the fluctuating daily 3H-2B release rate adopted by the dominants is a kind of strategic release and the 3H-2B release rate is a signal used to determine dominance.     

降雨随历时变化标度性质的探讨

降雨公式是水文计算的基本依据之一，也是工程师和水文学家十分关心的问题。长期以来水文中采用的降雨公式是基于大量降雨资料而建立起来的经验公式，多年的实践表明该公式能客观地反映降雨特性，计算结果符合实际，但是对该公式的理论基础却不太清楚。着眼于降雨在时间上的自相似性，将标度理论应用于降雨时间尺度问题，对降雨强度随历时变化的标度性质进行了研究，探讨了降雨公式的理论基础。由标度理论阐述了降雨标度性质（标度不变性）在时间尺度上的意义，并用此理论研究了成都望江楼站的降雨资料，计算了该站不同历时下降雨强度的各阶矩和变差系数，研究的结果表明，在一定的时间尺度范围内，降雨强度随历时变化确实具有多标度性质。最后由降雨强度随历时变化的标度性质推导出降雨公式，说明了降雨公式是降雨在时间尺度上标度特性的表示。