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Across the United Kingdom, the majority of local authoritieshave now completed their first phase of local air qualityreview and assessment work, as required under the AirQuality Strategy for England, Scotland, Wales and NorthernIreland (DETR, 2000a). Emerging from this first phasework is an anticipated suite of over 110 Air QualityManagement Areas (AQMAs). These areas are identifiedlocations where one or more of the national air qualityobjectives are predicted to exceed by specific target dates,and their spatial extent and shape is emerging as highlyvariable. Local authorities are guided to use a variety ofscientific tools to underpin the scientific assessments, anda consideration of uncertainty in both the tools used andsubsequent delineation of AQMAs is likely to affect theemerging management areas significantly. With subsidiarity underpinning the process of local air qualitymanagement (LAQM), local decision-making is anticipated toinfluence the outcome of the LAQM process in its entirety,with the declaration of AQMAs necessitating the preparationand implementation of air quality action plans. UKexperience of the effective management of local air quality,through the designation of AQMAs, demonstrates a valuableframework for other European countries developing mechanismsto manage air quality locally.  相似文献   
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Simulations of urban or natural environments created by graphics computer software are increasingly being utilized in research and applied contexts, and pertinent techniques have become highly sophisticated. However, the quality and utility of such presentation means still need careful validation. This issue was addressed in a series of lab and field studies. In the study reported here, a simulation of a suburban environment was presented to respondents (n=147) in several variations to investigate the effects of lighting (day/sun, day/fog, night), personal shadow (yes/no) and sound (on/off) on perceived simulation quality. The contingencies with related aspects (such as comprehension, recollection and appreciation of the simulated environment) were investigated as well. Based on a comprehensive conceptual framework, a set of scales measuring relevant cognitive and affective aspects was employed. Main results are that simulations were perceived as valid and acceptable, that appraisals differ according to lighting and time-of-day conditions, and that provision of sound enhances the perceived quality of presentations. The findings elucidate which factors are crucial for further improving simulations and clarify the validity of computer simulations for assessing existing and future environments.  相似文献   
505.
A study was carried out to evaluate the interaction effect of sewage and duration of consumption on the production traits of pullets. Intake of the test waters was a function of their degree of acceptability when intake was voluntary at periods of low ambient temperatures. The intiation of egg production in all groups began after five weeks of treatment and differences in egg weight of the groups was slight and not significant (P > 0.05). The effect of the sewage waters on growth was pronounced only when the birds were in lay and the alum-treated sewage promoted higher body weight gain. The feed conversion ratio and the feed intake were not affected significantly (P > 0.05) by the interaction, and both had the same trend. The eggshell thickness was sensitive to changes in ambient temperature.  相似文献   
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ABSTRACT .A study was conducted in two arid zones to determine the effect of saline water applied to various crops growing in coarse-textured soil, using trickle irrigation. The test crops responded most favorably to this new method of water application in terms of plant development and yield. The method provides us with the possibility of raising the permissible salinity level of irrigation water, and thus to increase the water reserves suitable for agricultural use in the world.  相似文献   
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Model studies were and are still being used to verify certain theories in ground-water flow systems in general. In complex cases, the model studies may be extremely useful especially when a theoretical rigorous analysis does not exist. The models cannot be considered entirely satisfactory due to the several drawbacks in each type in addition to the normal human errors in experimentation. This paper is concerned only with the viscous flow models. However, a brief summary of the other types of models, which may possibly be used in connection with salt water intrusion problems is given. It should be noted that some of such experiments are not directly related to the field of salt water intrusion. Two main types lie within this category: The gravity flow systems which are analogous to some phases of salt intrusion problems and problems in oil fields which bear general similarities to sea water intrusion zones. In oil fields, gas cycling studies give valuable information to sea water problems. Model studies are used by hydraulic engineers, geologists, petroleum engineers, physicists, foundation engineers and several other professional groups.  相似文献   
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Physiological Age of Host Plant Foliage and Survival of Gypsy Moth Larvae   总被引:1,自引:0,他引:1  
The pH of leaf homogenates of common birch (Betula verrucosa L.), a food plant of gypsy moth (Lymantria dispar L.) larvae, was measured at different times of day in the course of leaf organogenesis, and midgut pH was measured in gypsy moth larvae phenotypically differing in the color of the hypodermis at the fifth instar. A possible relation between these parameters is discussed.  相似文献   
510.
Monitoring of A. uralensis populations in Kamenskii raion, Sverdlovsk oblast, in 1992–2002 and in Kaslinskii raion, Chelyabinsk oblast, in 2000–2001 revealed an increase in the proportion and diversity of minor morphogenetic aberrations and abnormalities in the structure of the cranium along the axis of the Eastern Ural Radioactive Trace (EURT). The samples from the southern and northern parts of the EURT (contaminated with 90Sr to 500 and 4 Ci/km2, respectively) were characterized by directed deviations from the control with respect to the frequencies of phenes of nonmetric cranial traits and an increase in the level of their fluctuating asymmetry in young females, which is indicative of epigenetic rearrangements in populations living in a radioactive environment.  相似文献   
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