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71.
There is currently a considerable emphasis on delivering major renewable energy infrastructure projects. Such projects will have impacts on local communities; some impacts may be perceived as positive but others will be viewed more negatively. Any just regulatory process for considering and permitting such infrastructure will need to heed the concerns that local communities voice. But what counts as a local voice? In this paper it is argued that the regulatory process plays a performative role, constructing what counts as a local voice. Furthermore, this has consequences for how regulatory deliberations proceed and the outcomes of regulatory processes. The empirical basis for this argument is a study of major offshore renewable energy infrastructure in England and Wales and the way that it is regulated through a specific regime – the Nationally Significant Infrastructure Projects (NSIPs) regime established by the Planning Act 2008. Through a detailed study of eight projects that have passed through the regime, the analysis unfolds the way that the voices of local residents, local businesses, local NGOs and local authorities are constructed in the key boundary object of the Examining Authority’s report; it then draws out the implications for the mitigation measures that are negotiated. The research suggests that what counts as a local voice is constrained by how the performative role of the NSIPs regulatory regime differentiates between interests and suggests that new ways of giving voice to local people are required.  相似文献   
72.
• UVA pre-irradiation to TiO2 NPs enhanced its toxicity toward plant A. cepa. • UVA TiO2 NPs increased intracellular ROS, resulting in more cell damage. • Cell death enhanced cell permeability and increased uptake of NPs. • Being highly toxic (EC50 = 0.097 µmol/L), TC did not increase ROS generation. • Even at a low dose, TC enhanced the toxic potential of TiO2 NPs significantly. Usage of titanium dioxide nanoparticles (TiO2 NPs) and tetracycline (TC) has increased significantly in the present era. This leads to their release and accumulation in the environment. Both the compounds, individually, can have adverse toxic effects on the plants. Their binary mixtures can increase this degree of damage. The present study aimed to evaluate the toxicity of both the contaminants in individual and binary mixtures in Allium cepa. Further, the toxicity of TiO2 NPs upon UVA pre-irradiation was also measured. Results showed that UVA pre-irradiated NPs (UVA-TiO2 NPs) had a significant decrease in cell viability than their non-irradiated counterparts (NI-TiO2), denoting an increase in photocatalytic activity upon UVA pre-irradiation. Very low concentrations of TC (EC10 = 0.016 µmol/L) mixed with TiO2 NPs significantly increased the toxicity for both UVA-TiO2 and NI-TiO2 NPs. Intracellular ROS generation was significantly high for UVA-TiO2 NPs. However, TC did not have any effects on ROS production. Both the compounds exhibited genotoxic potential in A. cepa. Different chromosomal abnormalities like anaphase bridges, telophase bridges, laggard chromosomes, binucleate cells, etc. were observed. The binary mixture of UVA-TiO2 NPs and TC showed the highest chromosomal aberrations (64.0%±1.26%) than the mixture with NI-TiO2 or the individual contaminants. This decreased significantly after recovery (46.8%±1.92%), denoting the self-repair processes. This study proved that UVA-TiO2 NPs were more toxic and could be enhanced further when mixed with a sub-lethal concentration of TC. This work will help to assess the risk of both compounds in the environment.  相似文献   
73.
74.
Fire management planning for wildlands traditionally uses fire behavior estimated on the basis of worst-case weather at a specific site, but more realistic estimates can be obtained by considering the entire distribution of possible sites and weather conditions. Probability distributions of four widely used fire behavior variables were derived for four test cases in the Northern Rockies and Northern Intermountain Zone. The variables were rate of spread, fireline intensity, fire perimeter length-to-width ratio, and scorch height. Results were depicted in simple line graphs, three-dimensional pin graphs, and tables; they ranged from the cumulative probability of one variable to joint probabilities of four variables. Increasing the number of variables depicted increased the amount and scope of information available. Examples of interpreting the graphs and tables show how these techniques can be used in long-term fire program planning, fire suppression, management of various resources affected by fire, and interdisciplinary resource planning.  相似文献   
75.
Increasing evidence suggests that cognitive function is under selection in diverse taxa and that this results in different cognitive abilities in taxa experiencing different selective environments. For example, species inhabiting spatially complex environments might be expected to have good spatial learning ability. We investigated whether local habitat conditions influence learning by comparing the performance of two recently diverged species of threespine stickleback (Gasterosteus aculeatus complex) in a spatial learning task. The two species reside sympatrically in several lakes. Benthics occupy the spatially structured vegetated littoral zone, whereas limnetics occupy the spatially homogenous open-water pelagic zone. We trained fish to locate a hidden reward in a T-maze and asked whether they did so by learning a body-centred pattern of movement (turn left or right) or by using plant landmarks. Both benthics and limnetics used turn and landmark cues, but benthics learnt the task almost twice as quickly as limnetics. This difference is consistent with the hypothesis that benthic and limnetic sticklebacks are equipped with spatial learning abilities well suited to the spatial complexity of their littoral and pelagic habitats. Our findings add to the understanding of the evolution of learning.  相似文献   
76.
Most social primates live in cohesive groups, so travel paths inevitably reflect compromise: decision processes of individuals are obscured. The fission–fusion social organisation of the chimpanzee, however, allows an individual's movements to be investigated independently. We followed 15 chimpanzees (eight male and seven female) through the relatively flat forest of Budongo, Uganda, plotting the path of each individual over periods of 1–3 days. Chimpanzee movement was parsed into phases ending with halts of more than 20 min, during which individuals fed, rested or engaged in social activities. Males, lactating or pregnant females and sexually receptive females all travelled similar average distances between halts, at similar speeds and along similarly direct beeline paths. Compared to lactating or pregnant females, males did travel for a significantly longer time each day and halted more often, but the most striking sex differences appeared in the organisation of movement phases into a day's path. After a halt, males tended to continue in the same direction as before. Lactating or pregnant females showed no such strategy and often retraced the preceding phase, returning to previously visited food patches. We suggest that female chimpanzee movements approximate an optimal solution to feeding requirements, whereas the paths of males allow integration of foraging with territorial defence. The ‘continually moving forwards’ strategy of males enables them to monitor their territory boundaries—border checking—whilst foraging, generally avoiding the explicit boundary patrols observed at other chimpanzee study sites.  相似文献   
77.
This review focuses on the occurrence and treatment of arsenic (As) in the arid region of northern Mexico (states of Chihuahua and Coahuila) and bordering states of the southwestern US (New Mexico, Arizona, and Texas), an area known for having high As concentrations. Information assembled and assessed includes the content and probable source of As in water, soil, and sediments and treatment methods that have been applied in the area. High As concentrations were found mainly in groundwater, their source being mostly from natural origin related to volcanic processes with significant anthropogenic contributions near mining and smelting of ores containing arsenic. The affinity of As for solid phases in alkaline conditions common to arid areas precludes it from being present in surface waters, accumulating instead in sediments and shifting its threat to its potential remobilization in reservoir sediments and irrigation waterways. Factors such as oxidation and pH that affect the mobility of As in the subsurface environment are mentioned. Independent of socio-demographic variables, nutritional status, and levels of blood lead, cognitive development in children is being affected when exposed to As. Treatments known to effectively reduce As content to safe drinking water levels as well as those that are capable of reducing As content in soils are discussed. Besides conventional methods, emergent technologies, such as phytoremediation, offer a viable solution to As contamination in drinking water.  相似文献   
78.
ABSTRACT

To evaluate the validity of fixed-site fine particle levels as exposure surrogates in air pollution epidemiology, we considered four indicator groups: (1) PM25 total mass concentrations, (2) sulfur and potassium for regional air pollution, (3) lead and bromine for traffic-related particles, and (4) calcium for crustal particles. Using data from the European EXPOLIS (Air Pollution Exposure Distribution within Adult Urban Populations in Europe) study, we assessed the associations between 48-hr personal exposures and home outdoor levels of the indicators. Furthermore, within-city variability of fine particle levels was evaluated.

Personal exposures to PM2.5 mass were not correlated to corresponding home outdoor levels (n = 44, rS (S) =r o v ' Spearman (Sp) 0.07). In the group reporting neither relevant indoor sources nor relevant activities, personal exposures and home outdoor levels of sulfur were highly correlated (n = 40, rSp = 0.85). In contrast, the associations were weaker for traffic (Pb: n = 44, rSp = 0.53; Br: n = 44, rSp = 0.21) and crustal (Ca: n = 44, rSp = 0.12) indicators. This contrast is consistent with spatially homogeneous regional pollution and higher spatial variability of traffic and crustal indicators observed in Basel, Switzerland.

We conclude that for regional air pollution, fixed-site fine particle levels are valid exposure surrogates. For source-specific exposures, however, fixed-site data are probably not the optimal measure. Still, in air pollution epidemiology, ambient PM2.5 levels may be more appropriate exposure estimates than total personal PM2.5 exposure, since the latter reflects a mixture of indoor and outdoor sources.  相似文献   
79.
80.
Effects and implications of reduced and oxidised N, applied under 'real world' conditions, since May 2002, are reported for Calluna growing on an ombrotrophic bog. Ammonia has been released from a 10 m line source generating monthly concentrations of 180-6 microg m(-3), while ammonium chloride and sodium nitrate are applied in rainwater at nitrate and ammonium concentrations below 4mM and providing up to 56 kg N ha(-1) year(-1) above a background deposition of 10 kg N ha(-1) year(-1). Ammonia concentrations, >8 microg m(-3) have significantly enhanced foliar N concentrations, increased sensitivity to drought, frost and winter desiccation, spring frost damage and increased the incidence of pathogen outbreaks. The mature Calluna bushes nearest the NH3 source have turned bleached and moribund. By comparison the Calluna receiving reduced and oxidised N in rain has shown no significant visible or stress related effects with no significant increase in N status.  相似文献   
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