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Moving objects may pose an added threat to car occupants in motor vehicle accidents (MVAs). However, to our knowledge, there have only been two case studies published on the subject. For the present study, accident reports and photo documentation from MVAs were collected on-scene by dedicated paramedics. Emergency medical service personnel on-scene were interviewed as necessary. Potentially harmful unrestrained objects in the involved motor vehicles (MVs) were identified and categorised by type, weight and hardness. Seatback offset by unrestrained objects was noted. The patient injury distribution (Abbreviated Injury Scale (AIS) body regions) and severity (AIS severity scores and New Injury Severity Score (NISS) scores) were retrospectively determined from hospital and autopsy records, and their potential relationship to unrestrained objects was explored. A total of 190 accidents involving 338 MVs and 618 individuals were included. In total, 327 individuals (53%) were injured, and 61 (10%) died. 37 of 61 were not autopsied. The mean NISS was 17 (median 8, interquartile range (IQR) 1–27). Unrestrained objects were reported for 133 motor vehicles (39%) involving 293 individuals. 35% of the unrestrained objects found in the passenger compartment weighed >2 kg. In the boot, 32% of objects weighed >20 kg. Seatback offset associated with unrestrained objects was found for 45 individuals (15%). Unrestrained objects originally located in the boot (heavy luggage, groceries and tyres were the most frequently reported) had moved into the passenger compartment on impact in 27 cases, 24 of which were associated with seatback offset. An in-depth analysis was performed on 24 patients whose injuries were highly likely to be associated with unrestrained objects, as indicated by accident reports and medical documentation. Nineteen (79%) were involved in frontal collisions, and 12 (50%) died on-scene. The mean NISS was 51.7 (median 51, IQR 27–75) in the 17 (71%) patients with seatback offset and 37.2 (median 41, IQR 22.5–50) in the 7 (29%) without seatback offset. Seatback offset was associated with more severe head and thoracic injuries and an increased incidence of abdominal and pelvic injuries. Patients injured by unrestrained objects while sitting in unharmed car seats predominantly suffered head, cervical spine and thoracic injuries. Our results indicate a need for public information campaigns. The development of car backseats that can better sustain hits from heavy objects in the cargo boot is an important area for the motor vehicle production industry to explore.  相似文献   
13.
The metabolic pathways alternative to glycolytic energy (ATP) during growth of starter and nonstarter lactic acid bacteria were studied simulating the depletion of carbohydrates during cheese ripening. D-stat cultivation strategy with the gradual decrease of galactose concentration in tryptone-arginine feeding medium was used. With the decrease of galactose feeding, the biomass yield calculated on carbohydrate consumption (YX/HEX) and acetate/lactate production ratio of all strains increased. We assume that ATP and biomass yields improved by directing the pyruvate flow from lactate to acetate and that metabolic energy could be obtained either by producing acetate from carbohydrates or from arginine metabolism in ADI-positive strains. Four LAB strains out of eight produced ornithine from arginine indicating active arginine-deiminase (ADI) pathway. These ADI-positive strains achieved 3–10 times higher YX/HEX than ADI-negative strains in tryptone-arginine medium. Lactobacillus plantarum also used serine as an energy source. Starters and NSLAB strains using the amino acids arginine and serine or limited amounts of carbohydrates therefore have the potential to influence flavor production in cheese more efficiently.  相似文献   
14.
Responsive materials with birefringent optical properties have been exploited for the manipulation of light in several modern electronic devices. While electrical fields are often utilized to achieve optical modulation, magnetic stimuli may offer an enticing complementary approach for controlling and manipulating light remotely. Here, the synthesis and characterization of magnetically responsive birefringent microparticles with unusual magneto‐optical properties are reported. These functional microparticles are prepared via a microfluidic emulsification process, in which water‐based droplets are generated in a flow‐focusing device and stretched into anisotropic shapes before conversion into particles via photopolymerization. Birefringence properties are achieved by aligning cellulose nanocrystals within the microparticles during droplet stretching, whereas magnetic responsiveness results from the addition of superparamagnetic nanoparticles to the initial droplet template. When suspended in a fluid, the microparticles can be controllably manipulated via an external magnetic field to result in unique magneto‐optical coupling effects. Using a remotely actuated magnetic field coupled to a polarized optical microscope, these microparticles can be employed to convert magnetic into optical signals or to estimate the viscosity of the suspending fluid through magnetically driven microrheology.  相似文献   
15.
Electrodialytic removal of cadmium from wastewater sludge   总被引:9,自引:0,他引:9  
This paper presents for the first time laboratory results demonstrating electrodialytic removal of Cd from wastewater sludge, which is a method originally developed for soil remediation. During the remediation a stirred suspension of wastewater sludge was exposed to an electric dc field. The liquid/solid (ml/g fresh sludge) ratio was between 1.4 and 2. Three experiments were performed where the sludge was suspended in distilled water, citric acid or HNO3. The experimental conditions were otherwise identical. The Cd removal in the three experiments was 69, 70 and 67%, respectively, thus the removal was approximately the same. Chemical extraction experiments with acidic solutions showed that 5-10 times more Cd could be extracted from decomposed sludge than from fresh sludge. It is likely that the mobilization of Cd during decomposition of the sludge contributes to the efficient removal of Cd by the electrodialytic method. Extraction experiments and electrodialytic remediation using distilled water as enhancement agent showed that 0.3% Cd could be extracted from decomposed sludge during 1 week in closed flasks, whereas 69% was removed during 2 weeks of electrodialytic remediation in a stirred solution in contact with atmospheric air. A combination of aerobic decomposition and electrodialytic treatment could be a promising method for Cd removal from wastewater sludge, and thus Cd could be removed without the addition of chemicals to the sludge.  相似文献   
16.
The survival and distribution of microflora during laundering at 30 or 40°C in commercial U.S. and European Union (E.U.) detergents were determined in laboratory wash experiments. Four test strains—Staphylococcus epidermidis, S. aureus, Escherichia coli, and Pseudomonas aeruginosa—were evaluated on cotton textile. A significant survival and transfer between textiles were found for all four test strains washed in E.U. and U.S. color detergents (without bleach), whereas no survival was observed in bleach-containing detergents. Gram-negative strains generally survived in greater numbers than Gram-positive strains. A greater survival was observed in U.S. detergents at U.S. conditions (30°C, 12 min) than in E.U. detergents at E.U. conditions (40°C, 30 min). The adhesion of odorants to cotton and polyester textiles during washing and drying was studied using six previously identified odorants in laundry [ethylbutanoate, (Z)-4-heptenal, (E)-2-nonenal, 3-methylbutanoic acid, 2-methoxyphenol (guaiacol) and 4-methyloctanoic acid]. All odorants were effectively removed from cotton during wash, whereas the odorants were more strongly associated with polyester fibers. During wash, hydrophobic odorants [(Z)-4-heptenal, (E)-2-nonenal, and guaiacol] adhered more strongly to polyester than the acids. The odor formed by surviving skin microflora attached to textiles soiled with human sebum and sweat after laundering at 30°C was studied by sensory evaluation and aroma extract dilution analysis. Intensive odor was formed in both cotton and polyester textiles during prolonged drying. Generally, the odor formation in cotton swatches and the bacterial count of the wash liquor from cotton swatches were greater than the odor formation and bacterial count from polyester swatches. Odorants with animal notes (branched fatty acids) dominated the odor profile after prolonged drying. Polyester swatches possessed a more complex odor profile than cotton; in particular, aldehydes were more dominating in polyester than in cotton. A high-impact and malodorous component, 3-methylindole, was formed during prolonged drying in cotton. The study demonstrates that microbial odor formation is a dominating factor determining the odor impression of laundered cotton and polyester textiles dried under slow drying conditions. The initial soiling with aromatic components has an additional impact on the odor profile of polyester textiles after wash, due to strong adherence of odorants during the wash cycle.  相似文献   
17.
Reports an error in Social competence of adult chimpanzees (Pan troglodytes) with severe deprivation history: I. An individual approach by Elfriede Kalcher-Sommersguter, Signe Preuschoft, Karl Crailsheim and Cornelia Franz (Developmental Psychology, 2011[Jan], Vol 47[1], 77-90). Table 4 (p. 86) contained an error. The development of stationary vicinity for LD (late deprived) chimpanzees is misstated as ns. However, the difference is highly significant as p = .008. (The following abstract of the original article appeared in record 2011-00627-005.) Early social deprivation in highly social mammals interferes with their varying needs for security and stimulation. Toleration of social stimulation was studied in 18 adult ex-laboratory chimpanzees, who had been deprived for 16 to 27 years, during their 1st year after resocialization into 1 of 3 social groups. For this, a model of social competence was developed with 5 grades of social stimulation. The chimpanzees were classified as either early deprived (EDs; M = 1.2 years) or late deprived (LDs; M = 3.6 years) according to their age at entering the laboratory. EDs did not differ significantly from LD chimpanzees in the first 3 grades of social stimulation (i.e., the toleration of stationary vicinity, initiation of brief sociopositive contacts and gentle social play). LDs, however, clearly exceeded EDs in the 4th and 5th grade of social stimulation (i.e., their engagement in allogrooming and their toleration of passive close proximity). Furthermore, LDs showed greater social initiative in changing a social situation and had more expanded grooming networks compared with EDs. Moreover, in LDs and ED females, but not in ED males, toleration of stationary vicinity increased from the 1st to the 2nd year of group living. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
18.
Lateral heterostructures consisting of 2D transition metal dichalcogenides (TMDCs) directly interfaced with molecular networks or nanowires can be used to construct new hybrid materials with interesting electronic and spintronic properties. However, chemical methods for selective and controllable bond formation between 2D materials and organic molecular networks need to be developed. As a demonstration of a self‐assembled organic nanowire‐TMDC system, a method to link and interconnect epitaxial single‐layer MoS2 flakes with organic molecules is demonstrated. Whereas pristine epitaxial single‐layer MoS2 has no affinity for molecular attachment, it is found that single‐layer MoS2 will selectively bind the organic molecule 2,8‐dibromodibenzothiophene (DBDBT) in a surface‐assisted Ullmann coupling reaction when the MoS2 has been activated by pre‐exposing it to hydrogen. Atom‐resolved scanning tunneling microscopy (STM) imaging is used to analyze the bonding of the nanowires, and thereby it is revealed that selective bonding takes place on a specific S atom at the corner site between the two types of zig‐zag edges available in a hexagonal single layer MoS2 sheet. The method reported here successfully combining synthesis of epitaxial TMDCs and Ullmann coupling reactions on surfaces may open up new synthesis routes for 2D organic‐TMDC hybrid materials.  相似文献   
19.
In this paper an interactive video system for language learning will be discussed. The various parts and media contained in the system are connected by a multitude of links which lend themselves to explorative learning. Particular attention is given to the way the grammar section is incorporated and how it is accessed.Signe Marie Sanne is associate professor in the Department of Romance Languages and Literatures, University of Bergen. Since 1989 she has developed interactive video systems for language learning in Italian, Norwegian as a second language, English, French and Spanish. Her research interests are related to instructional design.  相似文献   
20.
This paper offers a systematic account of techniques to infer strong normalization from weak normalization that make use of syntactic translations from -terms to I-terms. We present variants of such techniques due to Klop, Sørensen, Xi, Gandy, and Loader.We show that all the translations, in some cases via adjustments, are special cases of a generic scheme of translations, known as permutative inner interpretations. Having established this, which is easy, the fact that all the translations can be used to reduce strong normalization to weak normalization can be obtained from a single, general result concerning permutative inner interpretations.Furthermore, we show that each of the translations can be obtained as the composition of Klop's well-known -translation and some other translation of independent interest. For instance, in the case of Xi's translation, this other translation is a thunkification translation.Finally we compare the above techniques in some detail to the intimately related techniques by de Vrijer and Girard.A main contribution of the paper is to compare the techniques of Gandy, Klop, and Girard in detail. For instance, we prove the main property of Gandy's translation without reference to functionals using instead ideas from Klop's translation.  相似文献   
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