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51.
52.
The environment in which biology exists has dramatically changed during the last decades. Life was formed during billions of years, exposed to, and shaped by the original physical forces such as gravitation, cosmic irradiation and the terrestrial magnetism. The existing organisms are created to function in harmony with these forces. However, in the late 19th century mankind introduced the use of electricity and during the very last decades, microwaves of the modern communication society spread around the world. Today one third of the world’s population is owner of the microwave-producing mobile phones. The question is: to what extent are living organisms affected by these ubiquitous radio frequency fields? Since 1988 our group has studied the effects upon the mammalian blood-brain barrier (BBB) by non-thermal radio frequency electromagnetic fields (RF-EMF). These have been revealed to cause significantly increased leakage of albumin through the BBB of exposed rats as compared to non-exposed animals—in a total series of about two thousand animals. One remarkable observation is the fact that the lowest energy levels give rise to the most pronounced albumin leakage. If mobile communication, even at extremely low energy levels, causes the users’ own albumin to leak out through the BBB, also other unwanted and toxic molecules in the blood, may leak into the brain tissue and concentrate in and damage the neurons and glial cells of the brain. In later studies we have shown that a 2-h exposure to GSM 915 MHz at non-thermal levels, gives rise to significant neuronal damage, seen 28 and 50 days after the exposure. In our continued research, the non-thermal effects (histology, memory functions) of long-term exposure for 13 months are studied as well as the effects of short term GSM 1,800 MHz upon gene expression. Most of our findings support that living organisms are affected by the non-thermal radio frequency fields. Studies from other laboratories in some cases find effects, while in other cases effects are not seen. Our conclusion is that all researchers involved in this field have the obligation to intensify this research in order to reduce, or avoid, the possible negative effects of the man made microwaves!  相似文献   
53.
Despite coastal mudflats serving as essential ecological zones interconnecting terrestrial/freshwater and marine systems, little is known about the profiles of antibiotic resistance genes (ARGs) in this area. In this study, characteristics of typical ARGs, involving both intracellular (iARGs) and extracellular ARGs (eARGs) at different physical states, were explored in over 1000 km of coastal mudflats in Eastern China. Results indicated the presence of iARGs and eARGs at states of both freely present or attached by particles. The abundance of eARGs was significantly higher than that of iARGs (87.3% vs 12.7%), and their dominance was more significant than those in other habitats (52.7%-76.3%). ARG abundance, especially for eARGs, showed an increasing trend (p < 0.05) from southern (Nantong) to northern (Lianyungang) coastal mudflats. Higher salinity facilitated the transformation from iARGs to eARGs, and smaller soil particle size was conducive to the persistence of eARGs in northern coastal mudflats. This study addresses the neglected function of coastal mudflats as eARGs reservoirs.  相似文献   
54.
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.  相似文献   
55.
Objective: The adaptive behavior of mobile phone–distracted drivers has been a topic of much discussion in the recent literature. Both simulator and naturalistic studies suggest that distracted drivers generally select lower driving speeds; however, speed adaptation is not observed among all drivers, and the mechanisms of speed selection are not well understood. The aim of this research was to apply a driver behavioral adaptation model to investigate the speed adaptation of mobile phone–distracted drivers.

Methods: The speed selection behavior of drivers was observed in 3 phone conditions including baseline (no conversation) and hands-free and handheld phone conversations in a high-fidelity driving simulator. Speed adaptation in each phone condition was modeled as a function of secondary task demand and self-reported personal/psychological characteristics with a system of seemingly unrelated equations (SURE) accounting for potential correlations due to repeated measures experiment design.

Results: Speed adaptation is similar between hands-free and handheld phone conditions, but the predictors of speed adaptation vary across the phone conditions. Though perceived workload of secondary task demand, self-efficacy, attitude toward safety, and driver demographics were significant predictors of speed adaptation in the handheld condition, drivers' familiarity with the hands-free interface, attitude toward safety, and sensation seeking were significant predictors in the hands-free condition. Drivers who reported more positive safety attitudes selected lower driving speeds while using phones.

Conclusion: This research confirmed that behavioral adaptation models are suitable for explaining speed adaptation of mobile phone distracted drivers, and future research could be focused on further theoretical refinement.  相似文献   

56.
Introduction: Instruments that assess the knowledge, attitude, and practice (KAP) of mobile phone use serve as a primary assessment tool on which mobile phone distracted driving interventions can be designed. The objective of this study is to develop and validate KAP-modeled survey instruments that measure the knowledge of mobile phone hazards while driving (KMPHD), the attitude of drivers towards mobile phone use while driving (AMPUD), and the practice of mobile phone use while driving (PMPUD). Method: This study was a cross-sectional analytical survey conducted in Ibadan, Nigeria. Three instruments were designed to measure KMPHD, AMPUD, and PMPUD. Content validity, item analysis, exploratory factor analysis were conducted, and items were excluded based on the collective results of the analysis. The domains of the constructs and the reliability of the instruments are reported. A confirmatory factor analysis was used to assess the regression weights of each item and the model fit. Results: From an original list of 13, 12, and 10 items in the KMPHD, AMPUD, and PMPUD instruments, a final list of 7, 5, and 7 items were generated in each survey instrument, respectively. Two domains of the knowledge of hazards and practice of mobile phone use were obtained, and attitude to phone use while driving was a single domain. The reliabilities (Cronbach alpha) of the KMPHD (0.881), AMPUD (0.954), and PMPUD (0.920) were sufficiently high. Also, all items in the three instruments had moderate-to-high regression coefficients, and the model fits of the instruments were good. Conclusions: This study provides KAP-modeled survey instruments that can be used to assess a population-based knowledge, attitude, and practice of mobile phone use while driving. Practical Applications: This survey instrument can be used in assessing baseline knowledge, attitude, and practice of phone use while driving and determine the focus and effectiveness of mobile phone-induced distracted driving interventions.  相似文献   
57.
Agent技术是近年来备受人们关注的软件开发技术。由于他的众多有用属性如自治性、自主性、自适应性等特性,使得人们对它的研究越来越多.笔者基于移动多Agent技术,通过对排课系统的基本问题、多Agent的智能排课的关键技术等的分析、研究并提出了基于移动多Agent技术的智能排课系统的解决方案.图1,参7.  相似文献   
58.
Marine protected areas (MPAs) have become a key component of conservation and fisheries management to alleviate anthropogenic pressures. For MPA networks to efficiently promote persistence and recovery of populations, ecological connectivity, i.e. dispersal and movement of organisms and material across ecosystems, needs to be taken into account. To improve the ecological coherence of MPA networks, there is hence a need to evaluate the connectivity of species spreading through active migration and passive dispersal. We reviewed knowledge on ecological connectivity in the Baltic Sea, Kattegat and Skagerrak in the northeast Atlantic and present available information on species-specific dispersal and migration distances. Studies on genetic connectivity are summarised and discussed in relation to dispersal-based analyses. Threats to ecological connectivity, limiting dispersal of populations and lowering the resilience to environmental change, were examined. Additionally, a review of studies evaluating the ecological coherence of MPA networks in the Baltic Sea, Kattegat and Skagerrak was performed, and suggestions for future evaluations to meet management needs are presented.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01684-x.  相似文献   
59.
为了解南通市移动通信基站电磁辐射时空分布特征,随机实测504座典型基站,着重从水平和垂直方向50 m范围内开展监测,并选取典型基站开展24 h连续监测。结果表明,南通市移动通信基站电磁辐射水平满足《电磁环境控制限值》(GB 8702—2014)中公众曝露控制限值要求;基站电磁辐射水平分布随距离增大呈现先增加后逐渐减小的趋势,地面最大投射点的距离基本为20~30 m;垂直方向最大监测值出现在与天线高度相近的楼层;24 h基站电场强度随时间呈明显变化,与话务量和数据流量分别进行相关性分析,相关系数为0.968 3和0.709 8,说明目前话务量仍是电磁辐射强度的重要影响因素。  相似文献   
60.
Trace analysis of volatile organic compounds (VOCs) during wildfires is imperative for environmental and health risk assessment. The use of gas sampling devices mounted on unmanned aerial vehicles (UAVs) to chemically sample air during wildfires is of great interest because these devices move freely about their environment, allowing for more representative air samples and the ability to sample areas dangerous or unreachable by humans. This work presents chemical data from air samples obtained in Davis, CA during the most destructive wildfire in California's history - the 2018 Camp Fire – as well as the deployment of our sampling device during a controlled experimental fire while fixed to a UAV. The sampling mechanism was an in-house manufactured micro-gas preconcentrator (µPC) embedded onto a compact battery-operated sampler that was returned to the laboratory for chemical analysis. Compounds commonly observed in wildfires were detected during the Camp Fire using gas chromatography mass spectrometry (GC–MS), including BTEX (benzene, toluene, ethylbenzene, m+p-xylene, and o-xylene), benzaldehyde, 1,4-dichlorobenzene, naphthalene, 1,2,3-trimethylbenzene and 1-ethyl-3-methylbenzene. Concentrations of BTEX were calculated and we observed that benzene and toluene were highest with average concentrations of 4.7 and 15.1 µg/m3, respectively. Numerous fire-related compounds including BTEX and aldehydes such as octanal and nonanal were detected upon experimental fire ignition, even at a much smaller sampling time compared to samples taken during the Camp Fire. Analysis of the air samples taken both stationary during the Camp Fire and mobile during an experimental fire show the successful operation of our sampler in a fire environment.  相似文献   
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