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1.
Catherine O'Leary Yvonne de Kluizenaar Piet Jacobs Wouter Borsboom Ian Hall Benjamin Jones 《Indoor air》2019,29(3):423-438
There is growing awareness that indoor exposure to particulate matter with diameter ≤ 2.5 μm (PM2.5) is associated with an increased risk of adverse health effects. Cooking is a key indoor source of PM2.5 and an activity conducted daily in most homes. Population scale models can predict occupant exposures to PM2.5, but these predictions are sensitive to the emission rates used. Reported emission rates are highly variable and are typically for the cooking of single ingredients and not full meals. Accordingly, there is a need to assess PM2.5 emissions from the cooking of complete meals. Mean PM2.5 emission rates and source strengths were measured for four complete meals. Temporal PM2.5 concentrations and particle size distributions were recorded using an optical particle counter (OPC), and gravimetric sampling was used to determine calibration factors. Mean emission rates and source strengths varied between 0.54—3.7 mg/min and 15—68 mg, respectively, with 95% confidence. Using a cooker hood (apparent capture efficiency > 90%) and frying in non‐stick pans were found to significantly reduce emissions. OPC calibration factors varied between 1.5 and 5.0 showing that a single value cannot be used for all meals and that gravimetric sampling is necessary when measuring PM2.5 concentrations in kitchens. 相似文献
2.
A generic analysis/design method for prismatic plate assemblies, using exact plate stiffnesses which are transcendental functions of loading and/or vibration frequency, has long been validated by the established program
. Hitherto vibrations were permitted only in analysis because design uses the Wittrick–Williams algorithm to modify the design predicted by a linear optimiser to be ‘just stable’ by scaling all layer thicknesses by F. This works because buckling loads, unlike the fundamental frequency f1, vary monotonically with F. The paper considers additionally scaling all plate breadths by Fα such that the buckling loads and f1 all vary monotonically with F. Theoretical consideration of simple limiting cases establishes bounds on the permitted values of α as 0.1≤α≤0.4. Then
results for typical stiffened panels demonstrate the method to be correct and are used to investigate the value of α which is most effective in returning stabilised designs of least mass and with least computation. 相似文献
3.
Slep Amy M. Smith; Cascardi Michele; Avery-Leaf Sarah; O'Leary K. Daniel 《Canadian Metallurgical Quarterly》2001,13(3):306
Aggression in dating relationships is associated with attitudes that justify its use. Attitudes about dating aggression are targeted by prevention efforts, contributing to a need to measure these attitudes sensitively, accurately, and multidimensionally. We describe two new measures of attitudes about aggression, each tapping different attitudinal components, and compare their psychometric properties with an existing scale. The 1st assesses attitudes about physical aggression in provocative situations. The 2nd taps attitudes about verbally aggressive, controlling, and jealous tactics against a dating partner. Data from 2,313 high school students were factor analyzed and cross-validated for each new scale. Compared with an existing measure, the scales had comparable levels of reliability and validity and improved response distributions. A 2nd-order factor analysis lends support to a multidimensional view of attitudes about dating aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Bandura Albert; O'Leary Ann; Taylor C. Barr; Gauthier Janel; Gossard Denis 《Canadian Metallurgical Quarterly》1987,53(3):563
In this experiment, we tested for opioid and nonopioid mechanisms of pain control through cognitive means and the relation of opioid involvement to perceived coping efficacy. Subjects were taught cognitive methods of pain control, were administered a placebo, or received no intervention. Their pain tolerance was then measured at periodic intervals after they were administered either a saline solution or naloxone, an opiate antagonist that blocks the effects of endogenous opiates. Training in cognitive control strengthened perceived self-efficacy both to withstand and to reduce pain; placebo medication enhanced perceived efficacy to withstand pain but not reductive efficacy; and neither form of perceived self-efficacy changed without any intervention. Regardless of condition, the stronger the perceived self-efficacy to withstand pain, the longer subjects endured mounting pain stimulation. The findings provide evidence that attenuation of the impact of pain stimulation through cognitive control is mediated by both opioid and nonopioid mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
The National Institute of Mental Health Multisite HIV Prevention Trial was a trial of an intervention to reduce sexual HIV risk behaviors among 3,706 low-income at-risk men and women at 7 U.S. research sites. The intervention, based on social- cognitive theory and designed to influence behavior change by improving expected outcomes of condom use and increasing knowledge, skills, and self-efficacy to execute safer sex behaviors, was effective relative to a control condition in reducing sexual risk behavior. At 3 months after completion of the intervention, measures of these potential mediators were higher in the intervention than in the control condition. Although the effect of the intervention on sexual risk behavior was significantly reduced when the variables were controlled statistically, supporting the hypothesis of their mediation of the intervention effect, most of the effect remained unexplained, indicating the influence of unmeasured factors on outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Hyer Lee; O'Leary William C.; Saucer Rayford T.; Blount John; Harrison William R.; Boudewyns Patrick A. 《Canadian Metallurgical Quarterly》1986,54(5):698
Attempted to distinguish among 3 types of inpatient veterans: (a) those with a diagnosis of posttraumatic stress disorder (PTSD) and combat experience; (b) those with a diagnosis other than PTSD and with combat experience; and (c) non-PTSD, noncombat patients. 75 Vietnam-era veterans classified in these groups were administered an assessment battery that included the Minnesota Multiphasic Personality Inventory (MMPI), State-Trait Anxiety Inventory, and Profile of Mood States. Results show no differences among the groups on premorbid variables. PTSD Ss, however, responded in a more pathological direction on psychometric and adjustment variables. A discriminant analysis using these variables correctly classified 85% of the Ss in the 3 groups. Time spent in combat was highly correlated with PTSD variables such as intrusion and numbing experiences; total stress; and symptoms of anxiety, depression, and anger. Results also cross-validate the MMPI-based PTSD scale developed by T. Keane et al (see record 1985-02913-001). (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
O'Leary K. Daniel; Barling Julian; Arias Ileana; Rosenbaum Alan; Malone Jean; Tyree Andrea 《Canadian Metallurgical Quarterly》1989,57(2):263
Community couples (N?=?272) were assessed in a longitudinal study of early marriage. More women than men reported physically aggressing against their partners at premarriage (44% vs. 31%) and 18 months (36% vs. 27%). At 30 months, men and women did not report significantly different rates of aggression (32% vs. 25%). However, using either the self-report or the partner's report, the prevalence of aggression for both men and women were pushing, shoving, and slapping. Conditional probability analyses indicated that the likelihood of physically aggressing at 30 months given that one had engaged in such aggression before marriage and at 18 months after marriage was .72 for women and .59 for men. Furthermore, 25–30% of the recipients of physical aggression at all three assessment periods were seriously maritally discordant at 30 months. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Increases in Calls to the CDC National STD and AIDS Hotline Following AIDS-Related Episodes in a Soap Opera 总被引:3,自引:1,他引:2
May G. Kennedy Ann O'Leary Vicki Beck Katrina Pollard Penny Simpson 《The Journal of communication》2004,54(2):287-301
In the United States, minority women are at risk of HIV infection and comprise a disproportionate share of daytime soap opera viewers. In August 2001, a soap opera subplot delivered HIV prevention messages to viewers and displayed the National STD and AIDS Hotline's toll-free number (800–342–2437) after 2 episodes. On both days, the number of attempted calls to the Hotline in the 1-hour time slots during and just after the 30-minute broadcasts rose dramatically. These increases in information-seeking behavior are consistent with predictions based on social cognitive theory, the health belief model, and various models of information processing. The increases also provide support for the Education-Entertainment approach and underscore the importance of a productive partnership between public health and the entertainment industry. 相似文献
9.
A number of empirical models for the valence band and conduction band hydrogenated amorphous silicon density of states functions are presented. Then, a relationship between these density of states functions and the imaginary part of the dielectric function is developed. The joint density of states function, which plays a key role in determining the spectral dependence of the imaginary part of the dielectric function, and is directly related to the valence band and conduction band density of states functions, is defined in the process. Joint density of states results, corresponding to a specific empirical density of states model, are then presented. Finally, the modeling results for the imaginary part of the dielectric function are contrasted with those of experiment and satisfactory agreement is found. 相似文献
10.
There have been many successful e‐businesses as well as many failed e‐businesses. The methods and practices that were evident in the development of both surviving e‐businesses and failed ones have much to teach us. Why did some e‐businesses fail while others survived? At present few guidelines exist to assist e‐business owners and managers wanting to succeed in their Internet‐based ventures. This study empirically investigated factors that may lead to e‐business success or failure; these were categorized as management, market, and financial factors. The results of a survey were combined with one‐on‐one interviews of venture capitalists who funded successful and failed e‐businesses. The results indicate that certain factors deemed applicable to an e‐business may have contributed to the firm’s eventual success or failure. 相似文献