Older drivers’ crashes in Queensland,Australia

Background

The growing proportion of older adults in Australia is predicted to comprise 23% of the population by 2030. Accordingly, an increasing number of older drivers and fatal crashes of these drivers could also be expected. While the cognitive and physiological limitations of ageing and their road safety implications have been widely documented, research has generally considered older drivers as a homogeneous group. Knowledge of age-related crash trends within the older driver group itself is currently limited.

Objective

The aim of this research was to identify age-related differences in serious road crashes of older drivers. This was achieved by comparing crash characteristics between older and younger drivers and between sub-groups of older drivers. Particular attention was paid to serious crashes (crashes resulting in hospitalisation and fatalities) as they place the greatest burden on the Australian health system.

Method

Using Queensland Crash data, a total of 191,709 crashes of all-aged drivers (17–80+) over a 9-year period were analysed. Crash patterns of drivers’ aged 17–24, 25–39, 40–49, 50–59, 60–69, 70–79 and 80+ were compared in terms of crash severity (e.g., fatal), at fault levels, traffic control measures (e.g., stop signs) and road features (e.g., intersections). Crashes of older driver sub-groups (60–69, 70–79, 80+) were also compared to those of middle-aged drivers (40–49 and 50–59 combined, who were identified as the safest driving cohort) with respect to crash-related traffic control features and other factors (e.g., speed). Confounding factors including speed and crash nature (e.g., sideswipe) were controlled for.

Results and discussion

Results indicated that patterns of serious crashes, as a function of crash severity, at-fault levels, road conditions and traffic control measures, differed significantly between age groups. As a group, older drivers (60+) represented the greatest proportion of crashes resulting in fatalities and hospitalisation, as well as those involving uncontrolled intersections and failure to give way. The opposite was found for middle-aged drivers, although they had the highest proportion of alcohol and speed-related crashes when compared to older drivers. Among all older drivers, those aged 60–69 were least likely to be involved in or the cause of crashes, but most likely to crash at interchanges and as a result of driving while fatigued or after consuming alcohol. Drivers aged 70–79 represented a mid-range level of crash involvement and culpability, and were most likely to crash at stop and give way signs. Drivers aged 80 years and beyond were most likely to be seriously injured or killed in, and at-fault for, crashes, and had the greatest number of crashes at both conventional and circular intersections. Overall, our findings highlight the heterogeneity of older drivers’ crash patterns and suggest that age-related differences must be considered in measures designed to improve older driver safety.     

高速钢热轧工作辊的组织特征与热疲劳行为研究

研究了不同工艺制造的高速钢热轧工作辊的微观组织、热疲劳性能和界面结合层特征,并讨论了制造工艺对高速钢组织和性能的影响。结果表明,从组织特征、使用性能和制造工艺复杂程度上来讲,CPC工艺制造的高速钢热轧工作辊表现出明显的优势。     

Acidities and catalytic activities of persulfonated poly(styrene-co-divinylbenzene) ion-exchange resins

A series of macroporous sulfonated poly(styrene-co-divinylbenzene) ion-exchange resins with varying levels of sulfonation have been prepared. The acidities of these resins have been measured calorimetrically by ammonia sorption. Catalytic activities have been measured in two liquid-phase reactions: the dehydration of 1-hexanol under flow conditions and the hydration of propene as a batch process. The molar enthalpies of ammonia sorption show that the strength of the acid sites increases as the level of sulfonation is increased; catalytic activities follow the same trend. The most active resins are those that have been sulfonated at levels above one sulfonic acid group per aromatic ring (persulfonated). These persulfonated resins also show higher thermal stabilities than conventional resins (sulfonated at just below one acid group per aromatic ring).     

Self-serving biases in the attribution of causality: Fact or fiction?

A review of the evidence for and against the proposition that self-serving biases affect attributions of causality indicates that there is little empirical support for the proposition in its most general form. Some support was found for the contention that individuals engage in self-enhancing attributions under conditions of success, but only minimal evidence suggested that individuals engage in self-protective attributions under conditions of failure. Moreover, it was proposed that the self-enhancing effect may not be due to motivational distortion, but rather to the tendency of people to (a) expect their behavior to produce success, (b) discern a closer covariation between behavior and outcomes in the case of increasing success than in the case of constant failure, and (c) misconstrue the meaning of contingency. (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Investigations of the reactions of monochloramine and dichloramine with selected phenols: examination of humic acid models and water contaminants

Our paper reports on the reactivities and orientations of two common phenols, phenol (2) and m-cresol (3), and some of their chlorinated intermediates with aqueous monochloramine, NH2Cl, and dichloramine, NHCl2. We also examined the further reactivity of 2,4,6-trichlorophenol (4) with the chloramines. The phenols are an important area of investigation because they are substituents in the humic acids and are common contaminants in water. m-Cresol (3) was found to be more reactive than phenol (2)with both chlorinating agents. Both NH2Cl and NHCl2were sufficiently reactive to chlorinate all positions ortho and para to the hydroxyl groups. Mono- and dichloramine showed the same orientation with 2 but different orientations in their reactions with the substituent phenols. Indophenol (as its salt) was formed to a minor extent at high pH but not at pH 9. Both NH2Cl and NHCl2 rapidly replaced the parachlorine in 2,4,6-trichlorophenol (4) to give a mixture of 2,6-dichloro-1,4-benzoquinone-4-(N-chloro) imine (5) and 2,6-dichloro-1,4-benzoquinone (18). Similar reactions occurwith 2,4,6-trichloro-m-cresol (17) and 2,4,6-trichloro-3-methoxyphenol (29). The products for 17 were confirmed by mass spectrometry (El and Cl), 1H NMR, 13C NMR, and IR; the products for 29 were confirmed by mass spectrometry (El and Cl) and IR. An ion radical mechanism is suggested to account for the chlorine replacement by the chloramines. [No side chain oxidation of the methyl group in 17 in H20 or ether occurred, with or without ultraviolet radiation.] Both 5 and 18 underwent further chlorination with NH2Cl or NHCl2. Imine 5 did not function as a chlorinated agent.     

Escherichia coli O157:H7 excretion by commercial feedlot cattle fed either barley- or corn-based finishing diets

Effective preharvest control measures for Escherichia coli O157:H7 in cattle may significantly reduce the incidence of human disease caused by this organism. The prevalence and magnitude of fecal E. coli O157:H7 excretion was evaluated in 15 pens (300 to 500 cattle per pen) of commercial feedlot cattle fed a barley-based finishing ration and compared with that in 15 pens of cattle fed a corn-based ration. Average E. coli O157:H7 prevalence was 2.4% in barley-fed cattle and 1.3% in the corn-fed cattle (P < 0.05), and average magnitude of fecal E. coli O157:H7 excretion was 3.3 log CFU/g in the barley-fed cattle and 3.0 log CFU/g in the corn-fed cattle (P < 0.01). Corn-fed cattle had lower average fecal pH values (5.85) than did barley-fed cattle (6.51) (P < 0.01), and the average total generic fecal E. coli concentration in this group of animals (6.24 log CFU/g) was greater than that in the barley-fed cattle (5.55 log CFU/g) (P < 0.01). Specific feed ingredients may impact the frequency and magnitude of fecal excretion of E. coli O157:H7 by cattle.     

Decreased production of inflammatory mediators in human osteoarthritic chondrocytes by conjugated linoleic acids

Osteoarthritic chondrocytes (OC) produce excessive prostaglandin E₂ (PGE₂) and nitric oxide (NO), which function as inflammation mediators in the pathogenesis of osteoarthritis (OA). This study examined the effect of CLA alone and in combination with other PUFA on the FA composition and the production of PGE₂ and NO in OC cultures isolated from OA patients. Human OC were grown in monolayer and treated with one of the following PUFA treatments: CLA, CLA+arachidonic acid (CLA/AA), CLA_EPA (CLA/EPA), linoleic acid (LA), LA+AA (LA/AA), LA+EPA (LA/EPA), and ethanol (as a vehicle control) at 10 and 20 μM for 6 d. Supplementation of PUFA at 10 μM for 6 d did not introduce any cytotoxic effects or morphological changes in OC, whereas 20 μM resulted in apoptosis. Cultures of OC treated with CLA, CLA/AA, and CLA/EPA had higher concentrations of CLA isomers, and these isomers were not detected in other treatments. Supplementation of CLA or LA alone to the OC led to a lower PGE₂ production compared to the control. Combination of CLA/EPA resulted in the lowest PGE₂ production in cultured OC. OC cultures treated with CLA were lower in NO production than the control, whereas the LA/AA treatment demonstrated the lowest NO production. The fact that CLA alone or in combination with other PUFA modulated PGE₂ and NO production in human OC cultures suggests that these 18∶2 isomers may have the potential to influence OA pathogenesis.     

Compatibility Condition in Theory of Solid Mechanics (Elasticity,Structures, and Design Optimization)

The strain formulation in elasticity and the compatibility condition in structural mechanics have neither been understood nor have they been utilized. This shortcoming prevented the formulation of a direct method to calculate stress and strain, which are currently obtained indirectly by differentiating the displacement. We have researched and understood the compatibility condition for linear problems in elasticity and in finite element structural analysis. This has lead to the completion of the “method of force” with stress (or stress resultant) as the primary unknown. The method in elasticity is referred to as the completed Beltrami-Michell formulation (CBMF), and it is the integrated force method (IFM) in the finite element analysis. The dual integrated force method (IFMD) with displacement as the primary unknown had been formulated. Both the IFM and IFMD produce identical responses. The IFMD can utilize the equation solver of the traditional stiffness method. The variational derivation of the CBMF produced the existing sets of elasticity equations along with the new boundary compatibility conditions, which were missed since the time of Saint-Venant, who formulated the field equations about 1860. The CBMF, which can be used to solve stress, displacement, and mixed boundary value problems, has eliminated the restriction of the classical method that was applicable only to stress boundary value problem. The IFM in structures produced high-fidelity response even with a modest finite element model. Because structural design is stress driven, the IFM has influenced it considerably. A fully utilized design method for strength and stiffness limitation was developed via the IFM analysis tool. The method has identified the singularity condition in structural optimization and furnished a strategy that alleviated the limitation and reduced substantially the computation time to reach the optimum solution. The CBMF and IFM tensorial approaches are robust formulations because both methods simultaneously emphasize the equilibrium equation and the compatibility condition. The vectorial displacement method emphasized the equilibrium, while the compatibility condition became the basis of the scalar stress-function approach. The tensorial approach can be transformed to obtain the vector and the scalar methods, but the reverse course cannot be followed. The tensorial approach outperformed other methods as expected. This paper introduces the new concepts in elasticity, in finite element analysis, and in design optimization with numerical illustrations.