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991.
The relationship between light and perceived safety at night is intuitively strong, yet theoretically and empirically its workings are largely unknown. Intelligent dynamic road lighting, which continuously adapts to the presence and behavior of users, can light the street only when and where it is needed. As such, it offers a solution to the energy waste and luminous pollution associated with conventional road lighting. With this innovation, however, new questions emerge about the effect of lighting on perceived safety. We need to consider not only how much lighting pedestrians need to feel safe, but also which parts of the street should be lit. In two experiments, we investigated the effect of different light distributions on perceived safety, and explored mediation by people's appraisal of three safety-related cues suggested in the literature: prospect (having an overview), escape (perceived escape possibilities), and refuge/concealment (perceived hiding places for offenders). Both experiments, one with stationary and one with walking participants, demonstrated that people prefer having light in their own immediate surroundings rather than on the road that lies ahead. This could be explained, partially, by changes in prospect, escape, and concealment. Against expectations, prospect was higher with lighting distributions in which participants' immediate surroundings, but not the more distant parts of the road, were most strongly lit. 相似文献
992.
993.
Controls on coarse wood decay in temperate tree species: birth of the LOGLIFE experiment 总被引:1,自引:0,他引:1
Cornelissen JH Sass-Klaassen U Poorter L van Geffen K van Logtestijn RS van Hal J Goudzwaard L Sterck FJ Klaassen RK Freschet GT van der Wal A Eshuis H Zuo J de Boer W Lamers T Weemstra M Cretin V Martin R Ouden Jd Berg MP Aerts R Mohren GM Hefting MM 《Ambio》2012,41(Z3):231-245
Dead wood provides a huge terrestrial carbon stock and a habitat to wide-ranging organisms during its decay. Our brief review highlights that, in order to understand environmental change impacts on these functions, we need to quantify the contributions of different interacting biotic and abiotic drivers to wood decomposition. LOGLIFE is a new long-term 'common-garden' experiment to disentangle the effects of species' wood traits and site-related environmental drivers on wood decomposition dynamics and its associated diversity of microbial and invertebrate communities. This experiment is firmly rooted in pioneering experiments under the directorship of Terry Callaghan at Abisko Research Station, Sweden. LOGLIFE features two contrasting forest sites in the Netherlands, each hosting a similar set of coarse logs and branches of 10 tree species. LOGLIFE welcomes other researchers to test further questions concerning coarse wood decay that will also help to optimise forest management in view of carbon sequestration and biodiversity conservation. 相似文献
994.
Acker CI Souza AC Dos Santos MP Mazzanti CM Nogueira CW 《Environmental science and pollution research international》2012,19(8):3481-3490
Purpose
In this study, we investigated the effect of diphenyl diselenide [(PhSe)2] on chlorpyrifos (CPF)-induced hepatic and hematologic toxicity in rats.Methods
Rats were pre-treated with (PhSe)2 (5?mg/kg) via the oral route (oral gavage) once a day for 7?days. On the eighth and ninth days, rats were treated with (PhSe)2 (5?mg/kg) 30?min prior to CPF (50?mg/kg, by subcutaneous route). The aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase activities were determined in plasma of rats. Lipid peroxidation, protein carbonyl, and non-protein thiol levels as well as catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, and gluthatione S-transferase activities were determined in livers of rats. Hematological parameters were also determined.Results
The results showed that CPF caused hepatic oxidative damage, as demonstrated by an increase in lipid peroxidation and protein carbonyl levels which was associated with a decrease in antioxidant defenses. CPF exposure caused a reduction in the leukocyte, indicating hematologic toxicity. (PhSe)2 was effective in attenuating these toxic effects caused by CPF exposure in rats.Conclusions
The results indicated that (PhSe)2 was effective in protecting the hepatic and hematologic toxicity induced by acute CPF exposure in rats. 相似文献995.
Mao L Qiu Y Kusano C Xu X 《Environmental science and pollution research international》2012,19(1):128-138
Purpose
Existing land-use regression (LUR) models use land use/cover, population, and traffic information to predict long-term intra-urban variation of air pollution. These models are limited to explaining spatial variation of air pollutants, and few of them are capable of addressing temporal variability. This article proposes a space–time LUR model at a regional scale by incorporating aerosol optical depth (AOD) data from the Moderate Resolution Imaging Spectroradiometer (MODIS). 相似文献996.
Ginebreda A Jelić A Petrović M López de Alda M Barceló D 《Environmental science and pollution research international》2012,19(4):958-970
Introduction
Lists of compounds resulting from environmental monitoring may be conveniently represented in a very general way using Pareto distributions, after ranking them on descending order according to their concentration or hazard quotient expressed as percentages, depending on whether the objective of the monitoring is focussed on mass load occurrence or risk assessment respectively. 相似文献997.
998.
Biochar derived from pyrolysis has received much attention recently as a soil additive to sequester carbon and increase soil fertility. Hydrochar, a brown, coal-like substance produced via hydrothermal carbonization, has also been suggested as a beneficial soil additive. However, before soil application, both types of char need to be tested for potential toxic effects. The aim of this study was to develop simple, inexpensive, and easy-to-apply test procedures to identify negative effects of chars but not to provide false-negative results. The following tests, based partly on ISO norm biotoxicity test procedures, were chosen: (i) cress germination test for gaseous phytotoxic emissions; (ii) barley germination and growth test; (iii) salad germination test; and (iv) earthworm avoidance test for toxic substances. Test reproducibility was ensured by carrying out each test procedure three times with the same biochar. Several modifications were necessary to adapt the tests for biochars/hydrochars. The tested biochar did not induce negative effects in any of the tests. In contrast, the beet-root chip hydrochar showed negative effects in all tests. In an extension to the regular procedure, a regrowth of the harvested barley shoots without further nutrient additions yielded positive results for the hydrochar, which initially had negative effects. This implies that the harmful substance(s) must have been degraded or they were water soluble and leached. Tests with a biochar and hydrochar showed that the proposed modified quick-check test procedures provide a fast assessment of risks and effects of char application to soils within a short period of time (<2 wk). 相似文献
999.
Johannes H. C. Cornelissen Ute Sass-Klaassen Lourens Poorter Koert van Geffen Richard S. P. van Logtestijn Jurgen van Hal Leo Goudzwaard Frank J. Sterck René K. W. M. Klaassen Grégoire T. Freschet Annemieke van der Wal Henk Eshuis Juan Zuo Wietse de Boer Teun Lamers Monique Weemstra Vincent Cretin Rozan Martin Jan den Ouden Matty P. Berg Rien Aerts Godefridus M. J. Mohren Mariet M. Hefting 《Ambio》2012,41(3):231-245
Dead wood provides a huge terrestrial carbon stock and a habitat to wide-ranging organisms during its decay. Our brief review highlights that, in order to understand environmental change impacts on these functions, we need to quantify the contributions of different interacting biotic and abiotic drivers to wood decomposition. LOGLIFE is a new long-term ‘common-garden’ experiment to disentangle the effects of species’ wood traits and site-related environmental drivers on wood decomposition dynamics and its associated diversity of microbial and invertebrate communities. This experiment is firmly rooted in pioneering experiments under the directorship of Terry Callaghan at Abisko Research Station, Sweden. LOGLIFE features two contrasting forest sites in the Netherlands, each hosting a similar set of coarse logs and branches of 10 tree species. LOGLIFE welcomes other researchers to test further questions concerning coarse wood decay that will also help to optimise forest management in view of carbon sequestration and biodiversity conservation. 相似文献
1000.
Medeiros Vinci R Jacxsens L Van Loco J Matsiko E Lachat C de Schaetzen T Canfyn M Van Overmeire I Kolsteren P De Meulenaer B 《Chemosphere》2012,88(8):1001-1007
Benzene is a volatile organic compound known to be carcinogenic to humans (Group 1) and may be present in food. In the present study, 455 food samples from the Belgian market were analyzed for benzene contents and some possible sources of its occurrence in the foodstuffs were evaluated. Benzene was found above the level of detection in 58% of analyzed samples with the highest contents found in processed foods such as smoked and canned fish, and foods which contained these as ingredients (up to 76.21 μg kg−1). Unprocessed foods such as raw meat, fish, and eggs contained much lower concentrations of benzene. Using the benzene concentrations in food, a quantitative dietary exposure assessment of benzene intake was conducted on a national representative sample of the Belgian population over 15 years of age. The mean benzene intake for all foods was 0.020 μg kg bw d−1 according to a probabilistic analysis. These values are below the minimum risk level for oral chronic exposure to benzene (0.5 μg kg bw d−1). 相似文献