The similar effects of low-dose ionizing radiation and non-ionizing radiation from background environmental levels of exposure

The meltdown and release of radioactivity (ionizing radiation) from four damaged nuclear reactors at the Fukushima Nuclear Facility in Japan in March 2011 continues to contaminate air and ocean water even 1 year later. Chronic exposure to low-dose ionizing radiation will occur over large populations well into the future. This has caused grave concern among researchers and the public over the very long period of time expected for decommissioning alone (current estimate from official sources is 30–40 years based on TEPCO in Mid-and long-term roadmap towards the decommissioning of Fukushima Daiichi nuclear power units 1–4, 2011) and the presumed adverse effects of chronic, low-dose ionizing radiation on children, adults and the environment. Ultimately, radioactive materials from Fukushima will circulate for many years, making health impacts a predictable concern for many generations (Yasunari et al. in PNAS 108(49):19530–19534, 2011). There is long-standing scientific evidence to suggest that low-dose ionizing radiation (LD-IR) and low-intensity non-ionizing electromagnetic radiation (LI-NIER) in the form of extremely low-frequency electromagnetic fields and radiofrequency radiation (RFR) share similar biological effects. Public health implications are significant for reconstruction efforts to rebuild in post-Fukushima Japan. It is relevant to identify and reduce exposure pathways for chronic, low-dose ionizing radiation in post-Fukushima Japan given current scientific knowledge. Intentional planning, rather than conventional planning, is needed to reduce concomitant chronic low-intensity exposure to non-ionizing radiation. These are reasonably well-established risks to health in the scientific literature, as evidenced by their classification by World Health Organization International Agency for Research on Cancer as Possible Human Carcinogens. Reducing preventable, adverse health exposures in the newly rebuilt environment to both LD-IR and LI-NIER is an achievable goal for Japan. Recovery and reconstruction efforts in Japan to restore the communications and energy infrastructure, in particular, should pursue strategies for reduction and/or prevention of both kinds of exposures. The design life of buildings replaced today is probably 35–50 years into the future. Cumulative health risks may be somewhat mitigated if the double exposure (to both chronic low-dose IR from the Fukushima reactors and LI-NIER [EMF and RFR] in new buildings and infrastructure) can be dealt with effectively in early planning and design in Japan’s reconstruction.     

Impact of environmental production conditions on productivity and efficiency: a case study of wheat farmers in Bangladesh

Environmental conditions significantly affect production, but are often ignored in studies analysing productivity and efficiency leading to biased results. In this study, we examine the influence of selected environmental factors on productivity and efficiency in wheat farming in Bangladesh. Results reveal that environmental production conditions significantly affect the parameters of the production function and technical efficiency, as well as correlates of inefficiency. Controlling for environmental production conditions improves technical efficiency by 4 points (p<0.01) from 86% to 90%. Large farms are more efficient relative to small and medium sized farms (p<0.01 and 0.05), with no variation among regions. Policy implications include soil fertility improvement through soil conservation and crop rotation, improvement in managerial practices through extension services and adoption of modern technologies, promotion of education, strengthening the research-extension link, and development of new varieties that have higher yield potential and are also suitable for marginal areas.     

An exploratory study of the effect of high and low fascination environments on attentional fatigue

According to attention restoration theory attentional fatigue can be renewed in environments where fascinating stimuli are present as they evoke effortless attention and allow directed attention to rest and be restored. The present study hypothesizes that performing an attention-orienting task in a state of attentional fatigue costs less in a high fascination than in a low fascination condition. In the former attentional shifts are expected to be facilitated because one can function in the involuntary mode. The high fascination condition is also expected to facilitate attention in the coding process and therefore to affect the likelihood of stimulus material to be remembered. To this end 31 subjects were mentally fatigued by performing a sustained attention test. Then they performed an ad hoc attention-orienting task inspired by Posner's paradigm and applied to 40 photographs of environments already assessed for their fascination value. Finally they performed an incidental memory task. As expected, only in the high fascination condition did participants show a significant benefit (reaction time reduction) in shifting attention between trials. The role of fascination on recall is less clear since it interacts with the naturalness of the scene.     

Comparative study on performances of a heat-pipe PV/T system and a heat-pipe solar water heating system

The heat-pipe solar water heating (HP-SWH) system and the heat-pipe photovoltaic/thermal (HP-PV/T) system are two practical solar systems, both of which use heat pipes to transfer heat. By selecting appropriate working fluid of the heat-pipes, these systems can be used in the cold region without being frozen. However, performances of these two solar systems are different because the HP-PV/T system can simultaneously provide electricity and heat, whereas the HP-SWH system provides heat only. In order to understand these two systems, this work presents a mathematical model for each system to study their one-day and annual performances. One-day simulation results showed that the HP-SWH system obtained more thermal energy and total energy than the HP-PV/T system while the HP-PV/T system achieved higher exergy efficiency than the HP-SWH system. Annual simulation results indicated that the HP-SWH system can heat the water to the available temperature (45°C) solely by solar energy for more than 121 days per year in typical climate regions of China, Hong Kong, Lhasa, and Beijing, while the HP-PV/T system can only work for not more than 102 days. The HP-PV/T system, however, can provide an additional electricity output of 73.019 kWh/m², 129.472 kWh/m², and 90.309 kWh/m² per unit collector area in the three regions, respectively.     

Experimental study on the effect of fly ash content in cemented paste backfill on its anti-sulfate erosion

ABSTRACT

In order to study the effect of fly ash content in cemented paste backfill (CPB) on its anti-sulfate erosion, the apparent phenomenon, strength development, and hydration products change the law of CPB with different fly ash content under long-term soaking of 5% sodium sulfate solution were studied by the macrotest and microanalysis, in addition, the mechanism of CPB anti-sulfate attack was analyzed by combining with a scanning electron microscope (SEM). The results indicated that the effect of sulfate environment on the strength of fly ash cemented paste backfill (FCPB) was mainly determined by the hydration products in the FCPB at different soaking times. In the early soaking stage, the formation of ettringite (AFt) in FCPB could improve its compactness, which was conducive to improving the strength of FCPB. In the late soaking stage, there were ettringite-type erosion damage and gypsum erosion-type damage internal of the FCPB with low content fly ash, resulting in microfracture, cracking of the FCPB, and reducing the strength. CPB with an appropriate content of fly ash could improve the internal structure of the FCPB to achieve the purpose of anti-sulfate erosion.     

Impact of industrial air pollutants on some biochemical parameters and yield in wheat and mustard plants

The present study was carried out to determine the impacts of SO₂, NO _x , SPM and RSPM, the most common air pollutants, generated mainly due to industries and vehicles, on some biochemical parameters and yield in wheat and mustard plants during 2006. The concentration of SO₂, NO _x , SPM and RSPM was determined at the polluted sites across the seasons, which ranged between 14.29–18.10, 20.81–22.43, 483.65–500.85 and 160.67–171.18 μg m⁻³, respectively. The wheat and mustard plants grown at polluted sites showed significant reduction in chlorophyll ‘a’, chlorophyll ‘b’, total chlorophyll, carotenoid, ascorbic acid, pH, relative water content and yield. The data were further analyzed using a two way ANOVA. It is concluded that the ambient air pollutants have a potential adverse impact on biochemical parameters, which further leads to a reduction in the yield of wheat and mustard crops.     

Comparative effect of Al, Se, and Mo toxicity on NO3(-) assimilation in sunflower (Helianthus annuus L.) plants

Here, we study the effect caused by three trace elements--Al, Se, and Mo--applied at the same concentration (100 microM) and in their oxyanionic forms--NaAl(OH)(4), Na(2)SeO(4), and Na(2)MoO(4)--on NO(3)(-) assimilation (NO(3)(-), nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), and glutamate synthase (GOGAT) activities, and concentrations of amino acids and proteins) in sunflower (Helianthus annuus L. var. Kasol) plants. The most harmful element for sunflower plants proved to be selenate, followed by aluminate. On the contrary, the application of molybdate had no negative effect on the growth of this plant, suggesting the possibility of using sunflower for the phytoremediation of this metal, mainly in agricultural zones used for grazing where the excess of this element can provoke problems of molybdenosis in ruminants (particularly in cattle). In addition, we found that the alteration of NO(3)(-) assimilation by SeO(4)(2-) and Al(OH)(4)(-) directly influences the growth and development of plants, foliar inhibition of NR activity by SeO(4)(2-) being more harmful than the decrease in foliar availability of NO(3)(-) provoked by Al(OH)(4)(-).     

尿中氚水和总氚的对比分析测定研究

用蒸馏液闪法测量尿中氚水浓度 ,用氧化蒸馏液闪法测量尿中总氚 (氚水和有机氚 )浓度。同时测量了 1999年核设施退役时接触氚人员的高于本底水平的尿中氚水和总氚浓度 72个样品。比较氚水和有机氚浓度 ,得到有机氚浓度占氚水浓度的平均值为 (5 4± 3 7) % ,其值与理论值和动物实验值基本相符     

Comparative study of transport processes of nitrogen, phosphorus, and herbicides to streams in five agricultural basins, USA

Agricultural chemical transport to surface water and the linkage to other hydrological compartments, principally ground water, was investigated at five watersheds in semiarid to humid climatic settings. Chemical transport was affected by storm water runoff, soil drainage, irrigation, and how streams were linked to shallow ground water systems. Irrigation practices and timing of chemical use greatly affected nutrient and pesticide transport in the semiarid basins. Irrigation with imported water tended to increase ground water and chemical transport, whereas the use of locally pumped irrigation water may eliminate connections between streams and ground water, resulting in lower annual loads. Drainage pathways in humid environments are important because the loads may be transported in tile drains, or through varying combinations of ground water discharge, and overland flow. In most cases, overland flow contributed the greatest loads, but a significant portion of the annual load of nitrate and some pesticide degradates can be transported under base-flow conditions. The highest basin yields for nitrate were measured in a semiarid irrigated system that used imported water and in a stream dominated by tile drainage in a humid environment. Pesticide loads, as a percent of actual use (LAPU), showed the effects of climate and geohydrologic conditions. The LAPU values in the semiarid study basin in Washington were generally low because most of the load was transported in ground water discharge to the stream. When herbicides are applied during the rainy season in a semiarid setting, such as simazine in the California basin, LAPU values are similar to those in the Midwest basins.     

Coercive versus cooperative pollution control: Comparative study of state programs to reduce erosion and sedimentation pollution in urban areas

This article examines coercive and cooperative approaches to implementing state urban erosion and sedimentation pollution control programs. State administrators report serious shortfalls in their ability to control sources of pollution, but comparison of more and less successful programs provides evidence of what states can do to make programs more effective. Key ingredients for a successful state effort include the use of coercion with both the private sector and local government, adequate staffing, application of severe sanctions when violations of state standards are detected, and provision of technical assistance. Many state programs lack one or more of those elements, which explains their inability to adequately control urban erosion and sedimentation pollution.     

国内外燃煤电厂汞排放控制技术比较分析

概述了燃煤电厂汞排放的危害及汞迁移转化的规律;对国内外燃煤电厂的汞排放浓度情况进行了比较;指出汞排放控制技术的研究目前主要集中在燃烧前燃料脱汞、燃烧中脱汞和燃烧后烟气脱汞等方面;以美国运用较多的燃煤电厂炉前溴盐添加剂脱汞技术为案例进行分析,在煤里加入4ppm的溴,由于溴化添加剂产生的汞脱除率约64%,总汞控制率达80%,汞排放浓度约为2.6μg/m3;如果加入12ppm的溴,由于溴盐添加剂产生的汞脱除率约76%,总汞控制率可达88%,汞排放浓度约为1.56μg/m3。因此,溴盐添加剂脱汞技术对我国目前装备了SCR和湿法脱硫装置的燃煤电厂脱汞具有较大的参考价值。     

干湿法氟化铝在铝电解生产中对污染物产生的对比分析

氟化铝是铝电解生产的主要原料之一,它的品质好坏直接影响着生产过程中污染物氟化氢的产生量。文章通过分析干、湿法氟化铝在铝电解生产使用中分别对氟化氢产生量的影响,建议推广干法氟化铝在铝电解生产中的应用,从而实现经济效益和环境效益双赢的目标。     

皖江城市群产业结构动态变化及比较优势分析

城市群形成发育的关键在于其内部产业结构的优化.首先,运用基尼系数法对皖江城市群1997-2006年三次产业的空间差异性做了动态时序分析;然后以2006年皖江城市群19个行业的就业数据为基础,运用区位熵和灰色关联分析法对皖江城市群8个地级市的产业比较优势和产业结构相似性进行了分析,得出的研究结果将为皖江城市群产业结构调整和新一轮皖江城市群开发提供科学依据.     

The effect of river pulsing on sedimentation and nutrients in created riparian wetlands

Sedimentation under pulsed and steady-flow conditions was investigated in two created flow-through riparian wetlands in central Ohio over 2 yr. Hydrologic pulses of river water lasting for 6 to 8 d were imposed on each wetland from January through June during 2004. Mean inflow rates during pulses averaged 52 and 7 cm d(-1) between pulses. In 2005, the wetlands received a steady-flow regime of 11 cm d(-1) with no major hydrologic fluctuations. Thirty-two sediment traps were deployed and sampled once per month in April, May, June, and July for two consecutive years in each wetland. January through March were not sampled in either year due to frozen water surfaces in the wetlands. Gross sedimentation (sedimentation without normalizing for differences between years) was significantly greater in the pulsing study period (90 kg m(-2)) than in the steady-flow study period (64 kg m(-2)). When normalized for different hydrologic and total suspended solid inputs between years, sedimentation for April through July was not significantly different between pulsing and steady-flow study periods. Sedimentation for the 3 mo that received hydrologic pulses (April, May, and June) was significantly lower during pulsing months than in the corresponding steady-flow months. Large fractions of inorganic matter in collected sediments indicated that allochthonous inputs were the main contributor to sedimentation in these wetlands. Organic matter fractions of collected sediments were consistently greater in the steady-flow study period (1.8 g kg(-1)) than in the pulsed study period (1.5 g kg(-1)), consistent with greater primary productivity in the water column during steady-flow conditions.     

华北地区CO2净排放比较优势时空特性分析

采用显示性比较优势理论,对2005-2010年我国华北地区5个省市人均CO2净排放和单位GDP CO2净排放的显示性比较优势做了分析;同时采用变异系数差异分析,结合空间自相关分析方法,对其空间格局和演变规律做了深入研究.研究发现,华北地区5省市人均CO2净排放高于全国平均水平.北京、天津、河北、山西4个省市出现下滑势头,而内蒙古自治区呈现大幅上升势头.山西单位GDP CO2净排放在全国最高,天津和北京低于全国平均水平.华北地区人均CO2净排放和单位GDP CO2净排放比较优势空间分别呈现负相关和正相关特性.     

Comparative effects of a tree crop (cocoa) and shifting cultivation on a forest soil in Nigeria

Summary This study examines the organic matter and nutrient levels in soils under a 26-year old cocoa plantation and shifting cultivation farmlands cropped with cassava and maize, in Nigeria. The characteristics of soils under the two contrasting agricultural modes were compared with those of soils under rain forest, in order to infer the differential effects. Relative to the forest levels, the soil organic matter and nutrient levels were not substantially reduced in soils under plantations of cocoa. This is largely because cocoa plantations replicate forest conditions. In contrast, organic matter and nutrient levels were much lower in shifting cultivation farmlands. This is attributable to the fact that the crops of cassava and maize have a low ground cover, they generate relatively small amounts of litter and so do not replicate forest conditions. Measures which might be adopted to conserve soil organic matter and nutrient status during shifting cultivation methods are discussed.Dr A.O. Aweto is a Senior Lecturer in the Department of Geography where Mr O.A. Obe was, until recently, a research worker.     

Quantification of the effect of fumigation on short- and long-term nitrogen mineralization and nitrification in different soils

The effect of soil fumigation on N mineralization and nitrification needs to be better quantified to optimize N fertilizer advice and predict NO(-)(3) concentrations in crops and NO(-)(3) leaching risks. Seven soils representing a range in soil texture and organic matter contents were fumigated with Cyanamid DD 95 (a mixture of 1,3-dichloropropane and 1,3-dichloropropene). After removal of the fumigant, the fumigated soils and unfumigated controls were incubated for 20 wk and N mineralization and nitrification were monitored by destructive sampling. The average short-term N mineralization rates (k(s)) were significantly larger in the fumigated than in the unfumigated soils (P = 0.025), but the differences in k(s) between fumigated and unfumigated soils could not be related to soil properties. The average long-term N mineralization rates (k(l)) were slightly larger in the fumigated soils but the difference with the unfumigated soils was not significant. Again, the differences in k(l) values could not be related to soil properties. Nitrification was inhibited completely for at least 3 wk in all soils, and an effect on nitrification could be observed up to 17 wk in one soil. An S-shaped function was fitted to the nitrification data corrected for N mineralization, and both the rate constant (gamma) and the time at which maximum nitrification was reached (t(max)) were strongly correlated to soil pH. However, since no correlations were found between the effect of fumigation on N mineralization and soil properties, taking into account the effects of fumigation in fertilizer advice and in the prediction of NO(-)(3) leaching risks will need further research.     

The effect of limited options and policy interactions on water storage policy in south Florida

Due to environmental constraints and reactive water management practices, water shortages exist across the Everglades ecosystem. A growing human population and continued wetlands damage and loss decrease the system's ability to provide water for sustained natural areas and for human uses. 'The Restudy' is an $8 billion plan to restore the Everglades while also continuing to provide water storage for urban and agricultural areas. The Restudy proposes a mix of water storage systems to provide for the predicted future growth in water demand. This mix is purported to be the most cost-efficient at providing water supplies, within the constraints of unchanged agricultural and urban land use. However, a sensitivity analysis of the Restudy's cost equation reveals that the total cost of water storage systems is influenced by real estate, land acquisition and water treatment costs. The interaction of land use and agricultural policies can affect these cost factors, and can change the relative cost-efficiency between storage systems. Real estate and land acquisition costs are affected by several 1996 Farm Bill provisions, which influence the cost of aboveground water storage systems versus Aquifer Storage and Recovery systems. The Governor's Commission for a Sustainable South Florida recommendations also influence the water storage options available to the Restudy. Due to the Restudy's initial assumptions and constraints, it may not advocate the most economically and ecologically sound remediation.