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321.
322.
Peter J. Silk Krista Ryall D. Barry Lyons Jon Sweeney Junping Wu 《Die Naturwissenschaften》2009,96(5):601-608
Analyses of the elytral hydrocarbons from male and female emerald ash borer, Agrilus planipennis Fairmaire, that were freshly emerged vs. sexually mature (>10 days old) revealed a female-specific compound, 9-methyl-pentacosane
(9-Me-C25), only present in sexually mature females. This material was synthesized by the Wittig reaction of 2-decanone with (n-hexadecyl)-triphenylphosphonium bromide followed by catalytic reduction to yield racemic 9-Me C25, which matched the natural compound by gas chromatography/mass spectrometry (retention time and EI mass spectrum). In field
bioassays with freeze-killed sexually mature A. planipennis females, feral males spent significantly more time in contact and attempting copulation with unwashed females than with females
that had been washed in n-hexane to remove the cuticular lipids. Hexane-washed females to which 9-Me-C25 had been reapplied elicited similar contact time and percentage of time attempting copulation as unwashed females, indicating
that 9-methyl-pentacosane is a contact sex pheromone component of A. planipennis. This is the first contact sex pheromone identified in the Buprestidae. 相似文献
323.
At the moment there is lack in the existing standards of a sizing procedure for media of more complex rheological behavior than Newtonian. A formulation for the generalized Reynolds number to calculate the viscosity correction factor and size safety valves for the flows of shear-thinning media is proposed in this work. The various formulations in the literature are validated in their accuracy of estimation of the mass flow rates of aqueous solutions of polyvinylpyrrolidone. Among them the generalized Reynolds number defined using the wall viscosity of the annulus between the seat and the disk gives the highest accuracy without overestimating the measured mass flow rates. On the base of these results this generalized Reynolds number is recommended for introduction in the next review of both ISO 4126-1 Part 1 and API 520 for the sizing of safety valves for shear-thinning media. 相似文献
324.
Farmer CM 《Traffic injury prevention》2003,4(1):38-44
Posted speed limit and police-reported injury codes are commonly used by researchers to approximate vehicle impact and occupant injury severity. In-depth crash investigations, however, produce more precise measures of crash and injury severity: change in velocity (delta-V) for crash severity and Abbreviated Injury Scale (AIS) scores for injury severity. A comparison of data from police crash reports with that gathered by National Automotive Sampling System (NASS) investigators highlighted the inadequacy of speed limit and police injury codes as proxies for delta-V and AIS injury severity. In general, delta-V increased with speed limit and higher values of AIS were associated with higher police-coded injury severity, but there were a number of anomalies. In particular, 49% of the drivers coded by police as having incapacitating injuries actually had sustained no more than minor injuries. This overstatement of injury severity was less frequent among male (44%) and elderly (37%) drivers than among female (53%) and nonelderly (50%) drivers. Also, 79% of the investigated vehicles that crashed on roads posted at 60 mph (96 km/h) or higher experienced a delta-V less than 25 mph (40 km/h). Safety studies depending on data from only police reports to establish injury or crash severity therefore could produce erroneous results. 相似文献
325.
326.
The paper describes a programme to develop the profile of major accident risk across a large multi national oil company. It describes the concepts, tools and processes for constructing the risk profile and some of the key learnings from the exercise. 相似文献
327.
The present study developed a nomological network that theoretically linked time urgency to related variables. To test the proposed relationships, time urgency, achievement strivings (AS), and impatience/irritability (II) were utilized as predictors of health and performance 18 months later. Multivariate canonical correlation analyses provided support for a complex nomological network among the predictors and the outcome measures. Redundancy coefficients and a rotated structure matrix were employed to identify two significant dimensions, labeled crammers and organizers, that linked the predictors with the outcome measures. The results also indicated that the time urgency subcomponents were differentially related to several health outcomes. These findings provide further validity evidence for the time urgency construct, and they suggest that time urgency variables should be considered as important predictors of both health and performance outcomes. Directions for future research on time urgency are discussed. © 1998 John Wiley & Sons, Ltd. 相似文献
328.
The purpose of this review was to summarize the literature on occupational, acute, traumatic hand injury and suggest directions for future research. In 1996, the leading occupational injury treated in United States' hospital emergency departments was an acute hand injury (e.g. laceration, crush or fracture). These injuries affected 30% of an estimated 3.3 million injured workers (990,000). Cuts and lacerations of the fingers ranked third after back and leg strains in the number of lost workday cases in the USA in 1994. The incidence rate of hand injuries studied in seven manufacturing environments around the world ranged from 4 to 11 per 100 workers per year. Workers aged 24 years or less had the highest risk of hand injury. Men had higher rates of severe hand injury than women.Despite the high frequency and significant amount of lost work time associated with these injuries, they are poorly understood from an etiological perspective. There is only one case-control study of occupational hand injury in the literature. That study suggested an important role for both fixed (age) and transient risk factors (doing an unusual task) at the time of the injury. More analytic epidemiological research is needed to identify potentially modifiable risk or protective factors (e.g. glove use) for acute hand injuries. In this regard, the case-crossover design, a relatively new epidemiological approach using cases as their own controls, could prove an efficient method for determining transient, modifiable risk factors for acute, occupational hand injury. 相似文献
329.
Stephanie C. Payne Mindy E. Bergman Jennifer M. Rodríguez Jeremy M. Beus Jaime B. Henning 《Journal of Loss Prevention in the Process Industries》2010,23(6):806-812
In order to evaluate the leading and lagging effects of process safety climate on incidents, we correlated safety climate survey data with organizational safety records from before and after the survey time period. We obtained data from a large, multinational organization with manufacturing operations involving a number of complex processes, chemicals, and hazardous substances. A total of 7728 employees from 62 sites responded to a safety climate survey in 2007. Individual responses were aggregated to the site-level and matched to site-level organizational records of process safety incidents 1 year before and 1 year after survey administration. Employees’ perceptions of good routine housekeeping were significantly related to environmental impact incidents as both a leading and a lagging indicator, as well as fires/explosions and property damage outcomes. Employees’ perceptions of systems to prevent backlogs and the extent to which health and safety problems are promptly corrected were also related to environmental releases and fires/explosions. Implications for process safety climate research, organizational survey strategies, and organizational climate change are discussed. 相似文献
330.
Twenty-five years of HAZOPs 总被引:7,自引:0,他引:7
The HAZOP or hazard and operability study was developed by ICI over 25 years ago and is in wide use today throughout the world. The technique is intended to review, in a formalized manner, the design of a system such as a chemical process production plant to detect potential problems in the operation of the system. The system has been extended for use on all types of production, storage and distribution units. Experience in the use of hazard studies has lead to the development of a phased approach with three distinct design phases. 相似文献