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81.
82.
Patricia Perez-Fuster Maria F. Rodrigo Maria Luisa Ballestar Jaime Sanmartin 《Accident; analysis and prevention》2013
In relative terms, Spanish motorcyclists are more likely to be involved in crashes than other drivers and this tendency is constantly increasing. The objective of this study is to identify the factors that are related to being an offender in motorcycle accidents. A binary logit model is used to differentiate between offender and non-offender motorcyclists. A motorcyclist was considered to be offender when s/he had committed at least one traffic offense at the moment previous to the crash. The analysis is based on the official accident database of the Spanish general directorate of traffic (DGT) for the 2003–2008 time period. A number of explanatory variables including motorcyclist characteristics and environmental factors have been evaluated. The results suggest that inexperienced, older females, not using helmets, absent-minded and non-fatigued riders are more likely to be offenders. Moreover, riding during the night, on weekends, for leisure purposes and along roads in perfect condition, mainly on curves, predict offenses among motorcyclists. The findings of this study are expected to be useful in developing traffic policy decisions in order to improve motorcyclist safety. 相似文献
83.
Abelardo Margolles José Antonio Moreno Lorena Ruiz Belkis Marelli Christian Magni Clara G. de los Reyes-Gavilán Patricia Ruas-Madiedo 《Journal of Bioscience and Bioengineering》2010,109(4):322-324
A synthetic gene coding for human growth hormone was expressed in Lactococcus lactis. The presence of the recombinant protein was assayed and quantified using ELISA tests. Human growth hormone was detected at high concentrations and displayed a biological activity similar to the one shown by commercial human growth hormone. 相似文献
84.
Hannan Tahir Carles Bona-Casas Andrew James Narracott Javaid Iqbal Julian Gunn Patricia Lawford Alfons G. Hoekstra 《Journal of the Royal Society Interface》2014,11(94)
Re-establishing a functional endothelium following endovascular treatment is an important factor in arresting neointimal proliferation. In this study, both histology (in vivo) and computational simulations (in silico) are used to evaluate neointimal growth patterns within coronary arteries along the axial direction of the stent. Comparison of the growth configurations in vivo and in silico was undertaken to identify candidate mechanisms for endothelial repair. Stent, lumen and neointimal areas were measured from histological sections obtained from eight right coronary stented porcine arteries. Two re-endothelialization scenarios (endothelial cell (EC) random seeding and EC growth from proximal and distal ends) were implemented in silico to evaluate their influence on the morphology of the simulated lesions. Subject to the assumptions made in the current simulations, comparison between in vivo and in silico results suggests that endothelial growth does not occur from the proximal and distal ends alone, but is more consistent with the assumption of a random seeding process. This may occur either from the patches of endothelium which survive following stent implantation or from attachment of circulating endothelial progenitor cells. 相似文献
85.
Damien Steyer Claude Erny Patricia Claudel Geneviève Riveill Francis Karst Jean-Luc Legras 《Food microbiology》2013
Geraniol produced by grape is the main precursor of terpenols which play a key role in the floral aroma of white wines. We investigated the fate of geraniol during wine fermentation by Saccharomyces cerevisiae. The volatile compounds produced during fermentation of a medium enriched with geraniol were extracted by Stir-bar sorptive extraction and analysed by GC–MS. We were able to detect and quantify geranyl acetate but also citronellyl- and neryl-acetate. The presence of these compounds partly explains the disparition of geraniol. The amounts of terpenyl esters are strain dependant. We demonstrated both by gene overexpression and gene-deletion the involvement of ATF1 enzyme but not ATF2 in the acetylation of terpenols. The affinity of ATF1 enzyme for several terpenols and for isoamyl alcohol was compared. We also demonstrated that OYE2 is the enzyme involved in geraniol to citronellol reduction. Fermenting strain deleted from OYE2 gene produces far less citronellol than wild type strain. Moreover lab strain over-expressing OYE2 allows 87% geraniol to citronellol reduction in bioconversion experiment compared to about 50% conversion with control strain. 相似文献
86.
Olivier Monga Mamadou Bousso Patricia Garnier Valrie Pot 《Computers & Geosciences》2009,35(9):1789-1801
This study is the follow-up to a previous one devoted to soil pore space modelling. In the previous study, we proposed algorithms to represent soil pore space by means of optimal piecewise approximation using simple 3D geometrical primitives: balls, cylinders, cones, etc. In the present study, we use the ball-based piecewise approximation to simulate biological activity. The basic idea for modelling pore space consists in representing pore space using a minimal set of maximal balls (Delaunay spheres) recovering the shape skeleton. In this representation, each ball is considered as a maximal local cavity corresponding to the “intuitive” notion of a pore as described in the literature. The space segmentation induced by the network of balls (pores) is then used to spatialise biological dynamics. Organic matter and microbial decomposers are distributed within the balls (pores). A valuated graph representing the pore network, organic matter and microorganism distribution is then defined. Microbial soil organic matter decomposition is simulated by updating this valuated graph. The method has been implemented and tested on real data. As far as we know, this approach is the first one to formally link pore space geometry and biological dynamics. The long-term goal is to define geometrical typologies of pore space shape that can be attached to specific biological dynamic properties. This paper is a first attempt to achieve this goal. 相似文献
87.
Electrochemical behavior of multifunctional graphene–polyimide nanocomposite film in two different electrolyte solutions 下载免费PDF全文
The effect of solvent on specific capacitance, bulk resistance, and charge/discharge capacity of graphene/polyimide composite films is studied by electrochemical methods. Composite films are synthesized by in situ condensation polymerization of poly (amic acid) in the presence of 50 wt % partly exfoliated graphene sheets followed by thermal curing at 250°C. Raman spectrum of the exfoliated graphene sheets show an increase in the ratio of ID to IG peak intensities from 0.167 to 0.222, suggesting increased defects in graphene basal planes. Electrochemical measurements carried out by using 0.4M potassium hexafluorophosphate (KPF6) dissolved in propylene carbonate and N‐methylpyrrolidone at 25°C show that the composite system exhibits both pseudocapacitance and supercapacitance behaviors, with an average capacitance of 40 and 36.5 F g?1, respectively. Bulk resistance of the composite obtained by using KPF6–propylene carbonate electrolyte solution is 300% lower than that obtained in KPF6–N‐methylpyrrolidone solution, with a fairly stable specific capacity of 85 μAhr g?1, with 80% retention observed after 30 charge–discharge cycles. Fourier transform infrared spectroscopy measurements show shifts in the cyclic imide carbonyl peak from 1778 to 1774 cm?1, which suggests that some form of interaction exists between the graphene and polyimide. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42673. 相似文献
88.
Christine M. Wickens Evelyn Vingilis Robert E. Mann Patricia Erickson Maggie E. Toplak Nathan J. Kolla Jane Seeley Anca R. Ialomiteanu Gina Stoduto Gabriela Ilie 《Accident; analysis and prevention》2015
Background
Despite limited empirical investigation, existing scientific literature suggests that individuals with a history or current diagnosis of conduct disorder (CD) may be more likely to demonstrate reckless and aggressive driving. Much of the limited research in this field examines the impact of childhood CD on driver behaviour and collision risk in young adults. Few if any, studies assess the impact of this disorder on driver behaviour beyond age 21 years. The current research is a population-based study of the impact of CD symptoms during childhood on the risk of engaging in driver aggression during adulthood.Methods
Data are based on telephone interviews with 5230 respondents who reported having driven in the past year. Data are derived from the 2011–2013 cycles of the CAMH Monitor, an ongoing cross-sectional survey of adults in Ontario, Canada aged 18 years and older. A binary logistic regression analysis of self-reported driver aggression in the previous 12 months was conducted, consisting of measures of demographic characteristics, driving exposure, problem substance use, alcohol- and drug-impaired driving, symptoms of attention deficit hyperactivity disorder, and childhood (before age 15) symptoms of CD.Results
When entered with demographic characteristics, driving exposure, and other potential confounders, childhood symptoms of CD increased the odds of reporting driver aggression more than two-fold (adjusted OR = 2.12). Exploratory analyses of the interaction between childhood symptoms of CD and age was not a significant predictor of driver aggression.Conclusions
Results suggest that symptoms of CD during childhood are associated with significantly increased odds of self-reported driver aggression during adulthood. Limitations and future directions of the research are discussed. 相似文献89.
James A. Birrell Kathrin Wrede Krzysztof Pawlak Patricia Rodriguez-Maciá Olaf Rüdiger Edward J. Reijerse Wolfgang Lubitz 《Israel journal of chemistry》2016,56(9-10):852-863
Hydrogenases catalyze the reduction of protons and oxidation of molecular hydrogen with high turnover frequencies and low overpotentials under ambient conditions. The heterodimeric [FeFe] hydrogenase from Desulfovibrio desulfuricans has an exceptionally high activity, and can be purified aerobically in an oxygen-stable inactive state. Recently, it was demonstrated that monomeric [FeFe] hydrogenases produced recombinantly in Escherichia coli can be artificially maturated by simply incubating the inactive “apo” enzymes with the synthetic [2Fe] cofactor mimic [Fe2(adt)(CO)4(CN)2]2−. Here, we use the same technique to produce the heterodimeric “apo” hydrogenase from D. desulfuricans in E. coli with a high yield and purity, and maturate the “apo” enzyme with [Fe2(adt)(CO)4(CN)2]2− to generate fully active “holo” enzyme. Interestingly, the rate of the artificial maturation process with D. desulfuricans is significantly slower than that for all other hydrogenases tested so far. The artificially maturated enzyme is spectroscopically and electrochemically identical to the native enzyme and shows high rates of hydrogen production (3700 s−1) and hydrogen oxidation (63,000 s−1). We expect that our highly efficient production method will facilitate future studies of this enzyme and other related [FeFe] hydrogenases from Desulfovibrio species. 相似文献
90.
Aurea M Almazan Desmond G Mortley Patricia J Grant 《Journal of the science of food and agriculture》1996,70(3):369-372
Sugar beet (Beta vulgaris L cv Great Western Sugar) was grown using the nutrient film technique with a half-strength modified Hoagland nutrient solution to determine its biomass yield and nutritional quality. After 6 months, storage root and foliage weights per plant were 493·1 g and 551·0 g, respectively. Sucrose content in the fresh storage root was 118·4 g kg−1 but was less than 10 g kg−1 in the fresh leaves and petioles. Some nutrients in the leaves and petioles were analysed to evaluate their potential as a leafy vegetable. Fresh leaf protein, total dietary fibre, mineral (Ca, Mg, Zn, Fe and K), vitamin (carotene, ascorbic acid and thiamine) and oxalic acid concentrations were similar to those of consumer-accepted green vegetables. 相似文献