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221.
OBJECTIVES: The horizontal distance between the back of the head and the frontal of the head restraint (backset) and rearward head movement relative to the torso (cervical retraction) were studied in different occupant postures and positions in a modern car. METHODS: A stratified randomized population of 154 test subjects was studied in a Volvo V70 year model 2003 car, in driver, front passenger, and rear passenger position. In each position, the subjects adopted (i) a self-selected posture, (ii) a sagging posture, and (iii) an erect posture. Cervical retraction, backset, and vertical distance from the top of the head restraint to the occipital protuberance in the back of the head of the test subject were measured. These data were analyzed using repeated measures ANOVA and linear regression analysis with a significance level set to p < 0.05. RESULTS: In the self-selected posture, the average backset was 61 mm for drivers, 29 mm for front passengers, and 103 mm for rear passengers (p < 0.001). Women had lower mean backset (40 mm) than men (81 mm), particularly in the self-selected driving position. Backset was larger and cervical retraction capacity lower in the sagging posture than in the self-selected posture for occupants in all three occupant positions. Rear passengers had the largest backset values. Backset values decreased with increased age. The average cervical retraction capacity in self-selected posture was 35 mm for drivers, 30 mm for front passengers, and 33 mm for rear passengers (p < 0.001). CONCLUSIONS: Future design of rear-end impact protection may take these study results into account when trying to reduce backset before impact. Our results might be used for future development and use of BioRID manikins and rear-end tests in consumer rating test programs such as Euro-NCAP. 相似文献
222.
Screening ecological risk assessment of persistent organic pollutants in Mediterranean sea sediments 总被引:5,自引:0,他引:5
A screening ecological risk assessment (ERA) was conducted for the first time in the Mediterranean basin in order to assess the toxicity posed to the benthic community by PCBs, DDTs and HCB in marine sediments. The characterization of the exposure was conducted by means of an extensive literature survey, generating a database with more than 2000 samples. The effects were assessed by the adoption of guidelines previously developed in the literature, because ecotoxicological information about persistent organic pollutants (POPs) in the Mediterranean sediments was lacking. Existing sediment quality guidelines (SQGs) for the target pollutants were compiled and consensus values were calculated for three different categories of toxicity, namely threshold effect concentration (TEC), probable effect concentration (PEC) and extreme effect concentration (EEC). The combination of exposure and effects characterization enabled the identification of some areas of concern in the vicinity of industrial and urban locations and in the mouths of the main Mediterranean rivers. Beyond the Mediterranean continental shelf, the level of toxicity for the benthic community was generally low. The evaluation of the toxicity induced by the mixture of the target pollutants spotted the importance of DDT contamination in the Mediterranean sediments, despite the fact that main inputs to the sea have been significantly reduced during the last decades. 相似文献
223.
Influence of volunteer and project characteristics on data quality of biological surveys 总被引:1,自引:0,他引:1
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Volunteer involvement in biological surveys is becoming common in conservation and ecology, prompting questions on the quality of data collected in such surveys. In a systematic review of the peer‐reviewed literature on the quality of data collected by volunteers, we examined the characteristics of volunteers (e.g., age, prior knowledge) and projects (e.g., systematic vs. opportunistic monitoring schemes) that affect data quality with regards to standardization of sampling, accuracy and precision of data collection, spatial and temporal representation of data, and sample size. Most studies (70%, n = 71) focused on the act of data collection. The majority of assessments of volunteer characteristics (58%, n = 93) examined the effect of prior knowledge and experience on quality of the data collected, often by comparing volunteers with experts or professionals, who were usually assumed to collect higher quality data. However, when both groups’ data were compared with the same accuracy standard, professional data were more accurate in only 4 of 7 cases. The few studies that measured precision of volunteer and professional data did not conclusively show that professional data were less variable than volunteer data. To improve data quality, studies recommended changes to survey protocols, volunteer training, statistical analyses, and project structure (e.g., volunteer recruitment and retention). 相似文献
224.
Eva Ramírez-Llodra Manuel Ballesteros Joan B. Company Luis Dantart Francisco Sardà 《Marine Biology》2008,153(3):297-309
The spatio-temporal variations in diversity, biomass and abundance of bathyal invertebrates (excluding decapod crustaceans,
which have been analysed elsewhere) from the North-western Mediterranean margin are described. The upper canyon (∼450 m),
middle slope (∼650 m) and lower slope (∼1,200 m) habitats were investigated throughout the year. The first two sites are visited
daily by a specialised commercial fisheries’ fleet, while the deeper site has not been impacted by fishing activities. A total
of 140 species from 12 phyla were collected from the 3 study areas. Of these, the Mollusca, Echinodermata, Polychaeta and
Cnidaria were the most speciose groups. The patterns of species diversity (H′) and evenness (E) were similar in time and space. The upper canyon and middle-slope sites were dominated by echinoderms and molluscs, while
the lower-slope site was dominated by cnidarians and sponges. Multifactorial ANOVA showed significant spatio-temporal differences
in the biomass and/or abundance only in echinoderms, molluscs, cnidarians and polychaetes. The faunal differences observed
were explained by habitat type, but not by season. The role of submarine canyons and commercial fishing on shaping the diversity
and biomass of bathyal Mediterranean invertebrates is discussed.
Luis Dantart: Deceased March 2005 相似文献
225.
Lindström ES Eiler A Langenheder S Bertilsson S Drakare S Ragnarsson H Tranvik LJ 《Ecology》2007,88(1):252-3; discussion 253-5
226.
Riparian zones are hotspots of plant species richness in temperate and boreal biomes. The phenomenon is believed to be caused primarily by river-related processes, and upland influences on riparian zones have received relatively little attention. We investigated the importance of discharge of groundwater derived from uplands on riparian patterns in vascular plant species composition. We found that groundwater discharge areas in riparian zones were 36-209% more species rich than non-discharge areas, depending on spatial scale (1-50 m wide transects from annual high-water levels to summer low-water levels) and river (one free-flowing and one regulated). Higher nitrogen availability and less drought stress during low river stages are suggested as the major causes for the higher species diversity in discharge areas. Riparian zones lacking groundwater discharge lost more species following water-level regulation than did discharge areas. This indicates that groundwater discharge areas are more resistant to regulation because both individual plants and plant populations may grow larger in discharge areas. These results demonstrate that riparian zones are controlled by water and nutrient input from upland parts of catchments in ways that have been overlooked despite more than three decades of research into linkages between stream ecosystems and their valleys. 相似文献
227.
Molina Carmen B. Sanz-Santos Eva Boukhemkhem Ali Bedia Jorge Belver Carolina Rodriguez Juan J. 《Environmental science and pollution research international》2020,27(31):38434-38445
Environmental Science and Pollution Research - Fe2O3-TiO2-clay heterostructures have been prepared using an organo-bentonite as support, which organophilic character favored the fixation of TiO2.... 相似文献
228.
Civeira Gabriela Lado Liares Marcos Vidal Vazquez Eva Paz Gonzlez Antonio 《Environmental management》2020,65(3):355-368
Environmental Management - This work quantified ecosystem services (ES) and the geographic gross product (GGP) at municipal level in the Metropolitan Region of Buenos Aires (MRBA), Argentina. The... 相似文献
229.
Christian Bjerregaard-Olesen Manhai Long Mandana Ghisari Bodil H Bech Ellen A Nohr Niels Uldbjerg Tine B Henriksen Jørn Olsen Eva C Bonefeld-Jørgensen 《Environmental science and pollution research international》2017,24(20):16592-16603
The use of the lipophilic persistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs) and several organochlorine pesticides (OCPs) has been prohibited for more than 30 years. In this study, we present the temporal trends of the lipophilic POP serum concentrations in Danish nulliparous pregnant women between 2011 and 2013. We randomly selected 197 pregnant women (gestational age 11–13) from the Aarhus Birth Cohort. The concentrations of the lipophilic POPs in the serum samples were analyzed using gas chromatography. The concentrations were corrected for total serum lipids. The statistical analysis was performed by regression analysis with adjustment for age, BMI, gestational age at blood draw, and smoking status. The serum concentrations of PCB 118, 138, 153, 156, 170, 180, 187, and hexachlorobenzen, trans-nonachlor, β-hexachlorocyclohexane (β-HCH), and p,p’-dichlorodiphenyldichloroethylene were lower in 2013 than in 2011. However, the oxychlordane concentration was lowest in 2011. The serum levels of most lipophilic POPs followed downward trends during the study period, which was expected, as these compounds has been banned for many years. The upward trend of oxychlordane was unexpected and presumably a chance finding. 相似文献
230.
John Munthe Eva Brorström-Lundén Magnus Rahmberg Leo Posthuma Rolf Altenburger Werner Brack Dirk Bunke Guy Engelen Bernd Manfred Gawlik Jos van Gils David López Herráez Tomas Rydberg Jaroslav Slobodnik Annemarie van Wezel 《Environmental Sciences Europe》2017,29(1):13