Output power distributions of terminals in a 3G mobile communication network

The objective of this study was to examine the distribution of the output power of mobile phones and other terminals connected to a 3G network in Sweden. It is well known that 3G terminals can operate with very low output power, particularly for voice calls. Measurements of terminal output power were conducted in the Swedish TeliaSonera 3G network in November 2008 by recording network statistics. In the analysis, discrimination was made between rural, suburban, urban, and dedicated indoor networks. In addition, information about terminal output power was possible to collect separately for voice and data traffic. Information from six different Radio Network Controllers (RNCs) was collected during at least 1 week. In total, more than 800000 h of voice calls were collected and in addition to that a substantial amount of data traffic. The average terminal output power for 3G voice calls was below 1 mW for any environment including rural, urban, and dedicated indoor networks. This is <1% of the maximum available output power. For data applications the average output power was about 6–8 dB higher than for voice calls. For rural areas the output power was about 2 dB higher, on average, than in urban areas. Bioelectromagnetics 33:320–325, 2012. © 2011 Wiley Periodicals, Inc.     

In situ LTE exposure of the general public: Characterization and extrapolation

In situ radiofrequency (RF) exposure of the different RF sources is characterized in Reading, United Kingdom, and an extrapolation method to estimate worst-case long-term evolution (LTE) exposure is proposed. All electric field levels satisfy the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference levels with a maximal total electric field value of 4.5 V/m. The total values are dominated by frequency modulation (FM). Exposure levels for LTE of 0.2 V/m on average and 0.5 V/m maximally are obtained. Contributions of LTE to the total exposure are limited to 0.4% on average. Exposure ratios from 0.8% (LTE) to 12.5% (FM) are obtained. An extrapolation method is proposed and validated to assess the worst-case LTE exposure. For this method, the reference signal (RS) and secondary synchronization signal (S-SYNC) are measured and extrapolated to the worst-case value using an extrapolation factor. The influence of the traffic load and output power of the base station on in situ RS and S-SYNC signals are lower than 1 dB for all power and traffic load settings, showing that these signals can be used for the extrapolation method. The maximal extrapolated field value for LTE exposure equals 1.9 V/m, which is 32 times below the ICNIRP reference levels for electric fields.     

A new algorithm quantifies the roles of wind and midge flight activity in the bluetongue epizootic in northwest Europe

The 2006 bluetongue (BT) outbreak in northwestern Europe had devastating effects on cattle and sheep in that intensively farmed area. The role of wind in disease spread, through its effect on Culicoides dispersal, is still uncertain, and remains unquantified. We examine here the relationship between farm-level infection dates and wind speed and direction within the framework of a novel model involving both mechanistic and stochastic steps. We consider wind as both a carrier of host semio-chemicals, to which midges might respond by upwind flight, and as a transporter of the midges themselves, in a more or less downwind direction. For completeness, we also consider midge movement independent of wind and various combinations of upwind, downwind and random movements. Using stochastic simulation, we are able to explain infection onset at 94 per cent of the 2025 affected farms. We conclude that 54 per cent of outbreaks occurred through (presumably midge) movement of infections over distances of no more than 5 km, 92 per cent over distances of no more than 31 km and only 2 per cent over any greater distances. The modal value for all infections combined is less than 1 km. Our analysis suggests that previous claims for a higher frequency of long-distance infections are unfounded. We suggest that many apparent long-distance infections resulted from sequences of shorter-range infections; a 'stepping stone' effect. Our analysis also found that downwind movement (the only sort so far considered in explanations of BT epidemics) is responsible for only 39 per cent of all infections, and highlights the effective contribution to disease spread of upwind midge movement, which accounted for 38 per cent of all infections. The importance of midge flight speed is also investigated. Within the same model framework, lower midge active flight speed (of 0.13 rather than 0.5 m s(-1)) reduced virtually to zero the role of upwind movement, mainly because modelled wind speeds in the area concerned were usually greater than such flight speed. Our analysis, therefore, highlights the need to improve our knowledge of midge flight speed in field situations, which is still very poorly understood. Finally, the model returned an intrinsic incubation period of 8 days, in accordance with the values reported in the literature. We argue that better understanding of the movement of infected insect vectors is an important ingredient in the management of future outbreaks of BT in Europe, and other devastating vector-borne diseases elsewhere.     

稻田甲螨的分类学研究（蜱螨亚纲：真螨目：甲螨亚目）

报道稻田甲螨种类共计30科36属42种,其中包括枝姣奥甲螨Pulchroppia(Pulchroppia)ramifera Wang et Li,sp.nov.。地枝奥甲螨Ramusella(Insculptoppia)humico-la Wang et Li,sp.nov.和长纹合若甲螨Zygoribatula longilinea Wang et Li,sp.nov.3新种,丝管囊甲螨Sacculozetes filosus Behan-Pelletier,1991,和尖足肋甲螨Podoribates cuspidatusSakakibara et Aoki,1966,2新纪录,此外,还提出一项新名Pulchroppia(Pulchroppia)mahunkai Wang et Li.本文除对新种和新纪录详细描述,对重要的优势种进行重描述外,还对稻田甲螨种群结构特点和存在争议的种类进行了讨论。     

字母位置对左右视野的识别影响

目的:考查左右视野中不同位置字母的辨别力。方法:采用探测刺激的方法对左右视野中字母位置的识别差异进行了研究。结果:通过SPSS15.0进行重复测量方差分析得出:①不同视野的错误率主效应显著(F=5.98,P<0.05);②探测位置的主效应非常显著(F=15.39,P<0.01);③不同视野与探测字母位置的交互作用非常显著(F=11.60,P<0.001)。结论:①位置错误多于字母错误,并且位置错误中所报告的字母更靠近中央凹。②左视野中的首字母有较差的辨别力,而右视野中的尾字母有较差的辨别力。③左视野中存在知觉系统的限制,而不是词汇识别策略中大脑左右半球的差异。④对词汇识别中大脑左半球平行加工、右半球系列加工的说法提出了质疑。     

Word learning and the cerebral hemispheres: from serial to parallel processing of written words

Reading familiar words differs from reading unfamiliar non-words in two ways. First, word reading is faster and more accurate than reading of unfamiliar non-words. Second, effects of letter length are reduced for words, particularly when they are presented in the right visual field in familiar formats. Two experiments are reported in which right-handed participants read aloud non-words presented briefly in their left and right visual fields before and after training on those items. The non-words were interleaved with familiar words in the naming tests. Before training, naming was slow and error prone, with marked effects of length in both visual fields. After training, fewer errors were made, naming was faster, and the effect of length was much reduced in the right visual field compared with the left. We propose that word learning creates orthographic word forms in the mid-fusiform gyrus of the left cerebral hemisphere. Those word forms allow words to access their phonological and semantic representations on a lexical basis. But orthographic word forms also interact with more posterior letter recognition systems in the middle/inferior occipital gyri, inducing more parallel processing of right visual field words than is possible for any left visual field stimulus, or for unfamiliar non-words presented in the right visual field.     

基于视觉搜索的外源易化和返回抑制脑机制研究

采用事件相关电位技术研究了在视觉搜索过程中的外源易化和返回抑制（inhibition of return,IOR）的相互关系。当外源注意保持在序列搜索过的位置上时,有一个延时反应(即IOR）,伴随其产生的相关脑电成分有：分布在后顶的潜伏期为200 ms 的正差异、分布在前额叶内侧靠左的潜伏期为240 毫秒的负差异,以及分布在两侧颞顶联合区的潜伏期为280 ms 的负差异。而当外源注意保持在平行搜索的位置上时,则出现了明显的易化效应,伴随其产生的脑电成分仅为分布在枕顶区域的潜伏期为280 ms 的负差异。这些结果表明,外源易化和IOR 涉及了不同的脑区和神经过程,从而支持两者在机制上是可分离性的观点。     

电磁辐射对大鼠海马Raf／MEK／ERK信号通路的影响

目的：研究电磁辐射后大鼠海马Raf／MEK／ERK通路相关信号分子的表达变化规律。探讨辐射损伤机制。方法：分别采用X波段高功率微波（X-HPM）、S波段高功率微波（S-HPM）及电磁脉冲（EMP）模拟源辐射大鼠,建立电磁辐射动物模型。通过Western blot检测海马Raf-1、磷酸化Raf-1和磷酸化ERK的表达。结果：三种电磁辐射后6h-14d,Raf-1表达均下调,以7d最为显著,至28d基本恢复,辐射组间未见明显差异。辐射后6h和7d,磷酸化Raf-1和磷酸化ERK表达均上调,6h较为明显,磷酸化ERK的变化以两微波组更为显著。S-HPM辐射后6h～14d,磷酸化Raf-1表达持续上调,磷酸化ERK的变化呈波浪状,以6h和3d为高峰。结论：Raf／MEK／ERK信号通路参与了电磁辐射所致海马损伤;ERK通路过度活化导致神经元凋亡与坏死可能是电磁辐射致认知功能障碍的重要机制。     

高压脉冲电场法提取干松针总黄酮及其体外抗氧化性检测

主要研究了高压脉冲电场法提取干松针总黄酮的工艺条件,并对松针总黄酮体外抗氧化性能进行初步分析.结果表明,最优的高压脉冲电场提取条件为:电场强度20 kV/cm,脉冲数8个,料液比1:50.松针总黄酮提取率的影响因素:料液比＞电场强度＞脉冲数.松针落叶中总黄酮物质对自由基清除能力随浓度的增加而升高,松针总黄酮对Fe~(3+)的还原能力比抗坏血酸强.     

Antimicrobial effect and shelf-life extension by combined thermal and pulsed electric field treatment of milk

Aims:  The impact of a combined hurdle treatment of heat and pulsed electric fields (PEF) was studied on native microbiota used for the inoculation of low-fat ultra-high temperature (UHT) milk and whole raw milk. Microbiological shelf-life of the latter following hurdle treatment or thermal pasteurization was also investigated.
Methods and Results:  UHT milk was preheated to 30°C, 40°C or 50°C over a 60-s period, pulsed for 50  μ s or 60  μ s at a field strength of 40 kV cm⁻¹ or for 33  μ s at 50 kV cm⁻¹. Heat and PEF reduced the microbial count by a maximum of 6·4 log in UHT milk (50°C; 50 kV cm⁻¹, 33  μ s) compared to 6·0 log ( P  ≥ 0·05) obtained by thermal pasteurization (26 s, 72°C). When raw milk was treated with a combination of hurdles (50°C; 40 kV cm⁻¹, 60  μ s) a 6·0 log inactivation of microbiota was achieved and microbiological milk shelf-life was extended to 21 days under refrigeration (4°C) vs 14 days in thermally pasteurized milk. Native microbiota was decreased by 6·7 log following conventional pasteurization.
Conclusions:  The findings suggest that heat and PEF achieved similar inactivation of native microbiota in milk and longer stabilization of microbiological shelf-life than thermal pasteurization.
Significance and Impact of the Study:  A hurdle approach of heat and PEF could represent a valid milk processing alternative to conventional pasteurization. Hurdle treatment might also preserve native milk quality better due to less thermal exposure.