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611.
Learning style models recognised that individuals differ in the sense learning modality of stimuli from which they best absorb, retain and process new information. The effect of sensory learning modalities on individual children’s sensitivity to sensory cues has so far been neglected. This paper reports on a study that sought to establish whether individual differences in children’s sensitivity to sensory cues in their perception of their school environmental features is influenced by their sensory learning modalities. Participants included Key Stage 1 and 2 pupils (N = 151) from four primary schools in South Gloucestershire, UK. The study used a child-friendly Visual, Auditory and Kinaesthetic questionnaire to establish children’s learning style modality. All children, independent of their learning style category, were exposed to three types of sensory cues, consisting of photo-safari, speech frequency and Global Positioning System. The analysis revealed that children’s sensitivity to sensory cues in their perception of school environmental features varied significantly between the three sensory learning modalities: visual, auditory and kinaesthetic. The implications of these findings on research, policy and practice are discussed. 相似文献
612.
静电放电测试是很多产品标准中常见的电磁兼容检测项目,本文叙述了静电放电测试中一些容易被测试人员忽视的细节,同时分析影响静电放电测试结果的因素,为EMC实验室和企业人员正确开展静电放电测试,和加强实验室管理提供帮助。 相似文献
613.
The effect of nonylphenol (NP) on growth, photochemistry and biochemistry of two green microalgae, Chlorella vulgaris and Selenanstrum capricornutum, and their ability to degrade NP were compared. The 96 h EC50 of C. vulgaris and S. capricornutum were greater than 4.0 and 1.0 mg L−1 NP, respectively, suggesting that the former species was more tolerant to NP. Both microalgae acclimated to NP stress through down-regulating their photosynthetic activities, including antenna size (chlorophyll a content), maximal photochemistry (Fv/Fm) and the light absorbed by PSII (ABS/CS0), but the dissipation of energy from reaction centres (DI0/RC) increased with the increase of NP concentrations. In C. vulgaris, the changes of these parameters were more significant than in S. capricornutum and recovered completely after a 96 h exposure. The antioxidant responses, such as GSH content, CAT and POD activities in C. vulgaris increased with the increase of NP concentrations after a 24 h exposure, but these changes disappeared with exposure time and recovered to the control levels after 96 h. In S. capricornutum, although GSH content, CAT and POD activities also increased when exposed to low- to moderate-NP concentrations, these values were significantly reduced at a high concentration (4 mg L−1) even after a 96 h exposure, indicating its antioxidant responses were significantly delayed. It is clear that the more NP-tolerant species, C. vulgaris, acclimated better with a faster recovery of its photosynthetic activity from the NP-induced damage, and exhibited more efficient and rapid responses to NP-induced oxidative stress. C. vulgaris also had a higher NP degradation ability than S. capricornutum. 相似文献
614.
Environmental change challenges local and global survival of populations and species. In a species-poor environment like the
Baltic Sea this is particularly critical as major ecosystem functions may be upheld by single species. A complex interplay
between demographic and genetic characteristics of species and populations determines risks of local extinction, chances of
re-establishment of lost populations, and tolerance to environmental changes by evolution of new adaptations. Recent studies
show that Baltic populations of dominant marine species are locally adapted, have lost genetic variation and are relatively
isolated. In addition, some have evolved unusually high degrees of clonality and others are representatives of endemic (unique)
evolutionary lineages. We here suggest that a consequence of local adaptation, isolation and genetic endemism is an increased
risk of failure in restoring extinct Baltic populations. Additionally, restricted availability of genetic variation owing
to lost variation and isolation may negatively impact the potential for evolutionary rescue following environmental change. 相似文献
615.
作为一种设计和分析的工具,计算流体力学(CFD)技术已成功应用于火电厂选择性催化还原(SCR)系统设计中,提供了大量物理模型或现场试验不能得到的数据。介绍了近年来国内外CFD技术在选择性催化还原(SCR)中的研究及应用进展,指出该研究目前存在的问题及发展方向。 相似文献
616.
通过对山西1368-1948年历史文献资料的搜集、整理和数学分析,对该区霜雪灾害等级、阶段、周期及其成因进行了研究。在这期间,山西共发生霜雪灾害419次,轻度106次、中度228次、重度85次。灾害变化可分为4个阶段,1368-1579年为第1阶段,1580-1699年为第2阶段,1700-1819年为第3阶段,1820-1948年为第4阶段。第1、3阶段距平值主要为负值,灾害频次较低,以轻、中度灾害为主。第2、4阶段距平值主要为正值,灾害频次较高,以中度和重度霜雪灾为主。小波分析表明,灾害存在着4个明显的周期,即10~13年、20年左右、45~50年和120年左右的周期。降雪或寒流引起的气温骤降至0℃以下是造成山西霜雪灾害的主要原因。共发生6次寒冷气候事件,分别出现在1578-1588、1591-1607、1631-1642、1669-1672、1690-1699和1830-1836年。出现3次异常寒冷灾害年,分别是1653、1892和1929年。 相似文献
617.
Sewage sludge amendment on agricultural soils has recently become a practice of heightened interest, as a consequence of sewage sludge production increase. This practice has benefits to soil and crops, however it may also lead to environmental contamination, depending on the characteristics of the fields. In order to define the suitability of the different agricultural fields to receive sewage sludge, a spatial tool is proposed. This tool, elaborated in GIS platform, aggregates different criteria regarding human exposure and environmental contamination.The spatial tool was applied to a case study in the region of Catalonia (NE of Spain). Within the case study, each step of the tool development is detailed. The results show that the studied region has different suitability degrees, being the appropriate areas sufficient for receiving the total amount of sewage sludge produced. The sensitivity analysis showed that “groundwater contamination”, “distance to urban areas”, “metals concentration in soil” and “crop type” are the most important criteria of the evaluation.The developed tool successfully tackled the problem, providing a comprehensive procedure to evaluate agricultural land suitability to receive sewage sludge as an organic fertilizer. Also, the tool implementation gives insights to decision makers, guiding them to more confident decisions, based on an extensive group of criteria. 相似文献
618.
TOMAZ LANGENBACH SIMONE J. MACIEL BARBARA C. V. NEVES ALLEN N. HAGLER DENISE M. MANO NEY V. VUGMAN 《Journal of environmental science and health. Part. B》2013,48(4):415-425
Microbial displacement in the soil is an important process for bioremediation and dispersal of wastewater pathogens. We evaluated cell movement in surface and subsurface red-yellow podzolic soil driven by advection and microbial motility and also survival of a microbial population at high pressure as is prevalent in deep soil layers. Pseudomonas fluorescens Br 12, resistant to rifampycin and kanamycin, was used as a model organism traceable in non-sterile soil. Our results showed that more than 40% of the P. fluorescens population survived under high pressure, and that microbial motility was not a major factor for its displacement in the soil. Cells were adsorbed in similar amounts to surface and subsurface soils, but more viable cells were present in the leachate of surface than in subsurface soils. The nature of this unexpected cell binding to the subsurface soil was studied by EPR, Mossbauer, NMR, and infrared techniques, suggesting iron had a weak interaction with microbes in soil. P. fluorescens movement in soil resulted mainly from convection forces rather than microbial motility. The transport of this bacterium along the transept toward groundwater encountered restricted viability, although it survived under high pressure conditions simulating those in deep soil layers. 相似文献
619.
Public parks are important to urban environments, residents, and visitors. Among other functions, they provide environmental services, such as air and water purification, and they increase both recreational opportunities and the attractiveness of the urban environment. Because of their importance, urban parks serve as public spaces that provide visitors and urban residents with rights to the city. This paper identifies the dearth of urban public parks in Accra-Tema city-region as worrying. The Accra Plan 1958 underscored the significance of green spaces and designated the coastal strip for parks development but the areas have been lost to various urban uses. We argue that the continual neglect of public parks within urban planning and community development schemes in the Accra-Tema city-region is a major concern because it is depriving the citizens a right to the city and its public spaces. A number of factors have worked adversely against the provision of public parks and green spaces in the city-region. These include development pressures, undue political interference, a complex land delivery system, and ad hoc planning. The paper concludes by offering policy suggestions as to how to resolve the dearth of parks and green spaces in the city-region. 相似文献
620.
Tourism and wetland conservation: application of travel cost and willingness to pay an entry fee at Ghodaghodi Lake Complex,Nepal
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Pramod Lamsal Kishor Atreya Krishna Prasad Pant Lalit Kumar 《Natural resources forum》2016,40(1-2):51-61
This study investigated the need and applicability of wetland tourism for resource conservation, using the case of Ghodaghodi Lake Complex, a Ramsar Site in western Nepal. The travel cost method (TCM) was used to determine the recreation potential of the lake complex, while the contingent valuation method (CVM) was used to calculate willingness of visitors to pay an entry fee as a payment vehicle for conservation. The per capita travel cost was found to be NPR 540 (US $7.71), while the mean willingness to pay an entry fee was NPR 34 (US $0.48) per visitor per entry. In addition, factors affecting wetland visitation rates and maximum willingness to pay were identified. Policy implications include the establishment of an entry fee system to offset conservation budgetary constraints, government investment in social benefits equating to at least per capita travel cost identified, and public‐private partnerships, with community participation in tourism promotion and wetland conservation. 相似文献