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21.
Jaarsma R Louwerse R Dijkstra A de Vries J Spaas JP 《Accident; analysis and prevention》2011,(4):1508-1515
For safety reasons a maximum speed limit of 60 km/h has been applied to minor rural roads in the Netherlands since 1998. To support this structurally, a part of these roads have also received additional physical measures in a so-called “low cost design” that is expected to reduce the number of traffic casualties by 10–20%. This measure has been implemented as much as possible in an area oriented way. To measure the design's effectivity, road safety in 20 specific rural areas was studied for 5 years before changes were implemented and, on average, 3.5 years thereafter. The study examined 851 km of roads, and a control study was done on 2105 km of comparable roads with a speed limit of 80 km/h. Both the study and the control roads are managed by water boards. Results show that the measures implemented on the roads in the 60 km/h-zones had statistically significant effects (p < 0.05) on casualty accidents (−24% overall), especially at intersections (−44%). This high reduction is probably caused by the concentration of technical interventions at intersections. Both outcomes are somewhat higher than previously expected and are comparable with the outcome of a meta-analysis of safety effects on area-wide urban traffic calming schemes. However, the cost-effectiveness ratio of the 60 km/h zones measures (€33,000 per prevented KSI-casualty) is much more favourable than the ratio in urban 30 km/h-zones (€86,000 per prevented KSI-casualty). 相似文献
22.
There is a paucity of literature relating to adolescent females who offend. This retrospective case note study of 100 consecutive referrals of girls aged 11-17 in care to an Adolescent Forensic Mental Health Service describes a group of disturbed girls at the extreme of the continuum. Sixty-eight girls had assaulted at least one person; a further 10 had caused damage to objects; 76 had deliberately harmed themselves; 90 had behaved in a way which was against the law in the 6 months prior to assessment, although only 42 had been charged with an offence. The referrers only correctly documented violent and aggressive behaviours in 54% of cases. Eleven girls had ever been statemented as having special educational needs. Seventy-one had been abused in some way, the majority having been multiply abused. Of the violent girls, 50% had misused substances. More abused girls had been violent to objects (49.3%) or set fires (21.1%). A high number of deliberately self-harming girls had a mental illness (13.6%), and a significantly high number of deliberately self-harming girls misused substances (50%) and had been sexually abused (53.9%). Areas for future research are discussed. 相似文献
23.
The distribution of coliform organisms on three California dairies which use a system of automatic flushing of alley ways and composted, recycled manure solids as free stall bedding for utilization of waste was studied. There was a wide distribution of Escherichia coli, Klebsiella, and Enterobacter and to less extent Citrobacter organisms. Klebsiella were not commonly in bovine feces. Composting manure solids effectively reduced coliform counts to few or to zero. However, if given proper conditions of moisture and temperature, coliforms could multiply to large numbers again in composted solids whether from survivors or from external contamination. Dried composted manure was satisfactory material for bedding of free stalls provided it was dried properly before application. 相似文献
24.
25.
B Renstrom S Rommelfanger CK Stone TR DeGrado KJ Carlson E Scarbrough RJ Nickles AJ Liedtke JE Holden 《Canadian Metallurgical Quarterly》1998,39(10):1684-1689
To study the sensitivity of two fatty acid tracers to changes in beta-oxidation, the myocardial retention kinetics of 125I-iodine-15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid (BMIPP) and 14-18F-fluoro-6-thia-heptadecanoic acid (FTHA) were compared in states of oxygen deprivation due to ischemia and hypoxia. METHODS: Nineteen swine were studied by extracorporeal perfusion of the three coronary arteries. Fatty acid beta-oxidation rates were determined by infusion of tritiated palmitate into the left anterior descending artery (LAD) and by measurement of labeled water production in the LAD perfusion bed. After a baseline period of 30 min, animals were divided into three groups and subjected to a 50-min intervention period. For the control group, there was no change in perfusion; for the ischemia group, there was a 60% decrease in LAD perfusion; and for the hypoxia group, the perfusion rate was unchanged, but venous blood was used as the LAD perfusate. Continuous infusion of FTHA and BMIPP into the LAD started 10 min into the intervention period and continued until the end of the intervention period. Retention rates of the two tracers were compared between the LAD and circumflex perfusion beds. RESULTS: No difference in beta-oxidation rate occurred from the baseline to the intervention period in the control group. A 50% reduction in beta-oxidation occurred in the ischemia group, and an 80% reduction occurred in the hypoxia group. No difference in retention of BMIPP or FTHA occurred in the control group. In the ischemia group, reduction in retention of both tracers occurred. However, in the hypoxia group, FTHA uptake was unchanged, whereas BMIPP retention increased compared to the circumflex arterial bed. CONCLUSION: Decreased retention of both BMIPP and FTHA occurred with ischemia, despite the known differences in metabolism of the two tracers. This difference in metabolism was further highlighted in the setting of hypoxia with increased BMIPP uptake. Thus, these results suggest that uptake of both FTHA and BMIPP tracks reduction of fatty acid utilization in myocardial ischemia but fails in tracking reduction of fatty acid oxidation during hypoxia. 相似文献
26.
A novel laser sensor for position measurements of technical solid-state surfaces is proposed. An external Fabry-Perot laser cavity is assembled by use of an antireflection-coated laser diode together with the technical surface. Mode locking results from pumping the laser diode synchronously to the mode spacing of the cavity. The laser cavity length, i.e., the distance to the measurement object, is determined by evaluation of the modulation transfer function of the cavity by means of a phase-locked loop. The mode-locking external-cavity laser sensor incorporates a resonance effect that results in highly resolving position and displacement measurements. More than a factor-of-10 higher resolution than with conventional nonresonant sensing principles is achieved. Results of the displacement measurements of various technical surfaces are reported. Experimental and theoretical investigations are in good agreement. 相似文献
27.
Assigned 40 female Long-Evans hooded rats to experimental or yoked-control groups receiving activity conditioning in a running wheel or immobility conditioning in a small open field. Following 10 days under these procedures, all Ss were curarized and punished either for the emission of high or low heart rates. The pretraining procedures contributed significantly more to the heart-rate changes observed under curare than did the reinforcement contingencies imposed under this latter condition. Implications are discussed with respect to the specificity of operant cardiovascular conditioning and the general issue of somatocardiovascular relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
Electronically nonadiabatic or non-Born-Oppenheimer (non-BO) chemical processes (photodissociation, charge-transfer, etc.) involve a nonradiative change in the electronic state of the system. Molecular dynamics simulations typically treat nuclei as moving classically on a single adiabatic potential energy surface, and these techniques are not immediately generalizable to non-BO systems due to the inherently quantum mechanical nature of electronic transitions. Here we generalize the concept of a single-surface molecular dynamics trajectory to that of a coupled-surface non-BO trajectory that evolves "semiclassically" under the influence of two or more electronic states and their couplings. Five non-BO trajectory methods are discussed. Next, we summarize the results of a series of systematic studies using a database of accurate quantum mechanical reaction probabilities and internal energy distributions for several six-dimensional model bimolecular scattering collisions. The test set includes three kinds of prototypical nonadiabatic interactions: conical intersections, avoided crossings, and regions of weak coupling. We show that the coherent switching with decay of mixing (CSDM) non-BO trajectory method provides a robust and accurate way to extend molecular dynamics to treat electronically nonadiabatic chemistry for all three kinds of nonadiabatic interactions, and we recommend it for molecular dynamics simulations involving nonradiative electronic state changes. 相似文献
29.
Kieboom J Kusumaningrum HD Tempelaars MH Hazeleger WC Abee T Beumer RR 《Journal of food protection》2006,69(11):2681-2686
Growing microorganisms on dry surfaces, which results in exposure to low water activity (a(w)), may change their normal morphology and physiological activity. In this study, the morphological changes and cell viability of Salmonella enterica serovar Enteritidis challenged to low a(w) were analyzed. The results indicated that exposure to reduced a(w) induced filamentation of the cells. The amount of filamentous cells at a(w) 0.94 was up to 90% of the total number of cells. Surviving filamentous cells maintained their membrane integrity after exposure to low a(w) for 21 days. Furthermore, cells prechallenged to low a(w), obtained with an ionic humectant, demonstrated higher resistance to sodium hypochlorite than control cells. These resistant cells are able to survive disinfection more efficiently and can therefore cause contamination of foods coming in contact with surfaces. This points to the need for increased attention to cleaning of surfaces in household environments and disinfection procedures in processing plants. 相似文献
30.
Reuben Lembani Jasper Knight Elhadi Adam Felix Kanungwe Kalaba 《The International journal of environmental studies》2020,77(4):581-601
ABSTRACT There is a need for accurate reporting of the second-growth forest in accounting for the contribution of secondary forests to achieving global carbon sequestration strategies. This study develops a model relating aboveground live biomass (AGLB) to Landsat reflectance measurements, and this method is used on multi spatial-temporal Landsat data (1998, 2001, 2004, 2011 and 2016) to assess changes in Miombo woodlands in Zambia. Results showed that the enhanced vegetation index was a better predictor of AGLB (r2 = 0.96; RMSE = 0.24 t ha?1) than the other assessed vegetation indices. Forest carbon stocks increased by an average rate of 3.65 ± standard error (SE): 0.56 t ha?1 yr?1 from 1998 to 2001, but a continual decline was evident for the periods 2001–2004 (?0.60 t ha?1 yr?1), 2004–2011 (?0.88 t ha?1 yr?1) and 2011–2016 (?2.03 t ha?1 yr?1). The study provides an empirical model for evaluating carbon stock changes. 相似文献