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Research output, citation impact, and the most-cited recent papers from Department of National Defence (Canada). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
1.4K
Citations
32.9K
h-index
77
i10-index
697
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Department of National DefenceMinistère de la Défense nationale

Top-cited papers from Department of National Defence

Work Extrinsic and Intrinsic Motivation Scale: Its value for organizational psychology research.
Maxime A. Tremblay, Céline Blanchard, Sara Taylor, Luc G. Pelletier +1 more
2009· Canadian Journal of Behavioural Science/Revue canadienne des sciences du comportement557doi:10.1037/a0015167

The Work Extrinsic and Intrinsic Motivation Scale (WEIMS) is an 18-item measure of work motivation theoretically grounded in self-determination theory (Deci & Ryan, 2000). The purpose of the present research was twofold. First, the applicability of the WEIMS in different work environments was evaluated. Second, its factorial structure and psychometric properties were assessed. Two samples of workers (military: N 465; civilians: N 192) voluntarily completed questionnaires. Using the WEIMS’s 3 indexes (work self-determination index, work self-determined and nonself-determined motivation, respectively), results of regression analyses were supportive of its ability to predict positive and negative criteria in the workplace. Results also showed the adequacy of both its construct validity and internal consistency. Its factorial structure was also invariant across samples. Finally, its quasi-simplex pattern and relationships with psychological correlates further supported the self-determination continuum. Overall, these findings provide evidence for the applicability as well as the reliability and validity of the WEIMS in organisational settings. Results are discussed in regard to the applicability of self-determination theory to the workplace.

Two brief interventions to mitigate a “chilly climate” transform women’s experience, relationships, and achievement in engineering.
Gregory M. Walton, Christine Logel, Jennifer M. Peach, Steven J. Spencer +1 more
2014· Journal of Educational Psychology554doi:10.1037/a0037461

In a randomized-controlled trial, we tested 2 brief interventions designed to mitigate the effects of a “chilly climate” women may experience in engineering, especially in male-dominated fields. Participants were students entering a selective university engineering program. The social-belonging intervention aimed to protect students’ sense of belonging in engineering by providing a nonthreatening narrative with which to interpret instances of adversity. The affirmation-training intervention aimed to help students manage stress that can arise from social marginalization by incorporating diverse aspects of their self-identity in their daily academic lives. As expected, gender differences and intervention effects were concentrated in male-dominated majors (20% women). In these majors, compared with control conditions, both interventions raised women’s school-reported engineering grade-point-average (GPA) over the full academic year, eliminating gender differences. Both also led women to view daily adversities as more manageable and improved women’s academic attitudes. However, the 2 interventions had divergent effects on women’s social experiences. The social-belonging intervention helped women integrate into engineering, for instance, increasing friendships with male engineers. Affirmation-training helped women develop external resources, deepening their identification with their gender group. The results highlight how social marginalization contributes to gender inequality in quantitative fields and 2 potential remedies.

Age in the development of closure ability in children.
Craig M. Mooney
1957· Canadian Journal of Psychology/Revue Canadienne de Psychologie352doi:10.1037/h0083717

CLOSURE IS the perception of an object or event which is not completely or immediately represented. Previous studies (1, 2, 3, 4, 5, 6, 7, 8, 9) have revealed marked individual differences in this perceptual ability, but have thrown little light on its development. Street's use of a Gestalt Completion Test with school children revealed no consistent or significant differences in scores attributable to age—which later prompted Thurstone (7, p. 9) to remark that the finding was of interest an indication that the test involves some factors which mature at an early age, and it may be taken as indicative of some fundamental and primitive function. The study by Verville and Cameron (9) of age and sex differences in the perception of incomplete pictures by adults revealed slight differences in reaction times and perceptual set attributable to age, but did not reveal a relationship between age and perceptual ability. Street's test comprised only thirteen items in its final form; the items were not of a single class; nor could the particular percepts be presumed to be universally familiar. Verville and Cameron used only ten items, and they were checking age differences between two groups of adults—those aged 16 to 23 and those aged 35 to 56. Both studies are open to the presumption that the tests, subjects, and procedures were not adequate to reveal an association between perceptual ability and age. The present study was undertaken to reveal, through an early age range, the likely association between closure ability and age. The procedure was designed to minimize the differential effects of prior perceptual experience through the use, on the one hand, of subjects of common social and educational background, and, on the other hand, of closure test-items representative of a single class of percepts that might be presumed to be universally familiar. In short, the aim was to correlate closure ability and age in a uni-dimensional perceptual domain.

Fiber Optic Sensors for Structural Health Monitoring of Air Platforms
Honglei Guo, Gaozhi Xiao, Nezih Mrad, Jianping Yao
2011· Sensors302doi:10.3390/s110403687

Aircraft operators are faced with increasing requirements to extend the service life of air platforms beyond their designed life cycles, resulting in heavy maintenance and inspection burdens as well as economic pressure. Structural health monitoring (SHM) based on advanced sensor technology is potentially a cost-effective approach to meet operational requirements, and to reduce maintenance costs. Fiber optic sensor technology is being developed to provide existing and future aircrafts with SHM capability due to its unique superior characteristics. This review paper covers the aerospace SHM requirements and an overview of the fiber optic sensor technologies. In particular, fiber Bragg grating (FBG) sensor technology is evaluated as the most promising tool for load monitoring and damage detection, the two critical SHM aspects of air platforms. At last, recommendations on the implementation and integration of FBG sensors into an SHM system are provided.

Moisture and Temperature Effects on the Mixed-Mode Delamination Fracture of Unidirectional Graphite/Epoxy
AJ Russell, K.N. Street
1985290doi:10.1520/stp36314s

The critical strain energy release rates for interlaminar fracture of unidirectional graphite/epoxy, both from a sharp notch and as a function of crack extension, were determined experimentally for combined tensile/shear loadings. Based on well-founded compliance techniques, a substantial database was generated over the temperature range −50°C to 100°C for both dry and moisture-saturated states. The fracture energy of the unreinforced epoxy matrix material was also measured. Initiation energies for delamination increased as the proportion of shear loading increased and as the temperature was lowered but were insensitive to moisture content. The fracture resistance to crack extension increased under tensile dominated loadings with both temperature and moisture content but remained constant for high shear loadings. The applicability of various mixed-mode fracture criteria to both the present data and to available literature data is examined. The Wu fracture model was modified to take into account plane strain conditions appropriate to delamination. Crack growth resistance behavior is discussed in terms of the micromechanisms occurring close to the crack tip.

Body Image, Eating Disorders, and the Drive for Muscularity in Gay and Heterosexual Men
Scott J. Duggan, Donald R. McCreary
2004· Journal of Homosexuality272doi:10.1300/j082v47n03_03

This Internet research project examined the relationship between consumption of muscle and fitness magazines and/or various indices of pornography and body satisfaction in gay and heterosexual men. Participants (N = 101) were asked to complete body satisfaction questionnaires that addressed maladaptive eating attitudes, the drive for muscularity, and social physique anxiety. Participants also completed scales measuring self-esteem, depression, and socially desirable responding. Finally, respondents were asked about their consumption of muscle and fitness magazines and pornography. Results indicated that viewing and purchasing of muscle and fitness magazines correlated positively with levels of body dissatisfaction for both gay and heterosexual men. Pornography exposure was positively correlated with social physique anxiety for gay men. The limitations of this study and directions for future research are outlined.

Intracellular targeting of exoenzyme S of <i>Pseudomonas aeruginosa</i> via type III‐dependent translocation induces phagocytosis resistance, cytotoxicity and disruption of actin microfilaments
Elisabet Frithz‐Lindsten, Yidong Du, Roland Rosqvist, Åke Forsberg
1997· Molecular Microbiology209doi:10.1046/j.1365-2958.1997.5411905.x

Exoenzyme S (ExoS) is an ADP‐ribosyltransferase secreted by the opportunistic pathogen Pseudomonas aeruginosa . The amino‐terminal half of ExoS exhibits homology to the YopE cytotoxin of pathogenic Yersinia . Recently, YopE was found to be translocated into the host cell by a bacteria–cell contact‐dependent mechanism involving the ysc ‐encoded type III secretion system. By using an approach in which exoS was expressed in different strains of Yersinia , including secretion and translocation mutants, we could demonstrate that ExoS was secreted and translocated into HeLa cells by a similar mechanism to that described previously for YopE. Similarly to YopE, the presence of ExoS in the host cell elicited a cytotoxic response, correlating with disruption of the actin microfilament structure. A similar cytotoxic response was also induced by a mutated form of ExoS with a more than 2000‐fold reduced ADP‐ribosyltransferase activity. However, the enzymatically active ExoS elicited a more definite rounding up of the HeLa cells, which also correlated with decreased viability of the cells after prolonged infection compared with cells infected with strains expressing mutated ExoS or YopE. This suggests that ExoS can act through two different mechanisms on the host cell. The expression of ExoS by Yersinia also mediated an anti‐phagocytic effect on macrophages. In addition, we present evidence that extracellularly located P. aeruginosa is able to target ExoS into eukaryotic cells. Taken together, our data suggest that P. aeruginosa , by analogy with Yersinia , targets virulence proteins into the eukaryotic cytosol via a type III secretion‐dependent mechanism as part of an anti‐phagocytic strategy.

INDIVIDUAL REACTIONS TO COMMUNITY DISASTER
James S. Tyhurst
1951· American Journal of Psychiatry190doi:10.1176/ajp.107.10.764

1. Psychiatric phenomena with respect to individual behavior under stress can be considered to lie along 4 main axes—the natural history of the process, reactions and factors at various stages of the process, and the psychodynamics of the interrelationships between reactions and factors in the continuum. 2. The natural history of individual behavior in acute community disasters that have been studied has been briefly described. This appears to fall into 3 overlapping phases—a period of impact, a period of recoil, and a posttraumatic period—each of which can be characterized according to stress, time, and psychological phenomena. 3. The relevance of the natural history method for this particular investigation and for psychiatric research in general has been briefly discussed.

Effect of modafinil on heat production and regulation of body temperatures in cold-exposed humans.
L. Bourdon, Ira Jacobs, W A Bateman, A. L. Vallerand
1994· PubMed173

Military personnel often undergo sustained operations that affect vigilance and alertness. Pharmacological agents may be used to enhance vigilance. Most such agents also have thermogenic properties. Whether a new promising stimulant, modafinil (Lyons and French, Aviat. Space Environ. Med. 1991; 62:432-435), has a beneficial effect on cold tolerance in the military context, is not known. The goal of this study was, therefore, to evaluate the effect of this new drug on thermal balance and the regulation of body temperatures in neutral conditions and when challenged by a cold exposure. Nine subjects underwent three trials each: two in the cold (3 h at rest, 10 degrees C) 0.5 h after the ingestion of either placebo or modafinil (200 mg), and one in thermal neutrality with modafinil (same conditions except Tdb = 29.3 degrees C). As expected, cold produced a drop in Tre and Tsk and an increase in Vo2. Although non-significant, there was a tendency for a slightly greater drop in Tre with modafinil (0.65 degrees C vs. 0.57 degrees C with placebo). A similar tendency was found for the heat debt (S) which was greater with modafinil than with placebo (16.1 +/- 0.7 vs. 14.7 +/- 0.6 kJ.kg-1, respectively, +9.5%, p = 0.11). This tendency appears to be the combined result of a slightly lower mean heat production during the test and a slightly greater mean dry heat loss. When tested at thermal neutrality, the drug had no effect on any thermal or metabolic parameters. The results demonstrate that the ingestion of a single dose of modafinil has no significant acute effect on thermal balance in neutral conditions and on thermoregulation in normal subjects exposed to cold. However, a tendency for slightly greater cooling was noted with modafinil. It is not known whether the use of modafinil in conjunction with sleep deprivation (a likely scenario) could magnify this effect.

Radiation Exposure From Diagnostic Imaging in Severely Injured Trauma Patients
Homer Tien, Lorraine N. Tremblay, Sandro Rizoli, Jacob Gelberg +3 more
2007· The Journal of Trauma: Injury, Infection, and Critical Care168doi:10.1097/ta.0b013e31802d9700

BACKGROUND: Trauma patients often require multiple imaging tests, including computed tomography (CT) scans. CT scanning, however, is associated with high-radiation doses. The purpose of this study was to measure the radiation doses trauma patients receive from diagnostic imaging. METHODS: A prospective cohort study was conducted from June 1, 2004 to March 31, 2005 at a Level I trauma center in Toronto, Canada. All trauma patients who arrived directly from the scene of injury and who survived to discharge were included. Three dosimeters were placed on each patient (neck, chest, and groin) before radiologic examination. Dosimeters were removed before discharge. Surface doses in millisieverts (mSv) at the neck, chest, and groin were measured. Total effective dose, thyroid, breast, and red bone marrow organ doses were then calculated. RESULTS: Trauma patients received a mean effective dose of 22.7 mSv. The standard "linear no threshold" (LNT) model used to extrapolate from effects observed at higher dose levels suggests that this would result in approximately 190 additional cancer deaths in a population of 100,000 individuals so exposed. In addition, the thyroid received a mean dose of 58.5 mSv. Therefore, 4.4 additional fatal thyroid cancers would be expected per 100,000 persons. In all, 22% of all patients had a thyroid dose of over 100 mSv (mean, 156.3 mSv), meaning 11.7 additional fatal thyroid cancers per 100,000 persons would result in this subgroup. CONCLUSION: Trauma patients are exposed to significant radiation doses from diagnostic imaging, resulting in a small but measurable excess cancer risk. This small individual risk may become a greater public health issue as more CT examinations are performed. Unnecessary CT scans should be avoided.

Allometric respiration/body mass data for animals to be used for estimates of inhalation toxicity to young adult humans
R. W. Bide, S. J. Armour, Eugene Yee
2000· Journal of Applied Toxicology162doi:10.1002/1099-1263(200007/08)20:4<273::aid-jat657>3.0.co;2-x

The relationship between body weight (BW) and respiratory minute volume (V(m)) was reviewed by collecting a database from the literature. The data were separated into anaesthetized and non-anaesthetized groups. Only young adult terrestrial mammals were included in the final data set. This database is the largest to be reported to date, is the first to separate the anaesthetized and non-anaesthetized groups and is matched to the target population of young, fit adult humans. The data set of non-anaesthetized animals contained 142 studies representing 2616 animals and 18 species from mice at 12 g body weight to horses and a giraffe at ca. 500 kg body weight. Analysis of the data indicated a power law (allometric) relationship between the minute volume and body weight. The resulting allometric equations for the empirical relationship between minute volume and body weight are: log(10)V()(m)= -0.302 + 0.809 log(10)BW and V(m) = 0.499 BW(0.809)where V(m) is the minute volume (l min(-1)) and BW is the body weight (kg). From these equations, a minute volume of 15.5 lmin(-1)was obtained for a 70 kg human in the same physiological and/or emotional state as the animals. The results of the analyses were compared to other empirical studies in the literature, the more recent of which also indicated a scaling factor of 0.8. The relationship between minute volume and body weight is recommended for use in estimating the inhalation toxicity to young adult humans (military personnel), because this is the first study to use a large database focused exclusively upon non-anaesthetized young adult terrestrial mammals.

Passive integrated optics elements based on long-range surface plasmon polaritons
Robert Charbonneau, Christine Scales, Ian Breukelaar, S. Fafard +3 more
2006· Journal of Lightwave Technology156doi:10.1109/jlt.2005.859856

Waveguides and passive integrated optics elements constructed from thin metal films of finite width embedded in a homogeneous background dielectric and propagating long-range surface plasmon polaritons (LRSPPs) have been characterized experimentally at free-space optical wavelengths near 1550 nm. Straight and curved waveguides, s-bends, four-port couplers, y-junctions, and Mach-Zehnder interferometers have been carefully characterized. Additionally, rigorous models based on modal decomposition have been proposed for all of these elements and validated via comparisons with the measurements. Excellent qualitative and quantitative agreement between theory and experiment is observed for all structures over all measurement wavelengths. It is hoped that this work will help further establish this new integrated optics technology, taking it beyond demonstrators.

A new rank correlation coefficient with application to the consensus ranking problem
Edward J. Emond, David W. Mason
2002· Journal of Multi-Criteria Decision Analysis155doi:10.1002/mcda.313

Abstract The consensus ranking problem has received much attention in the statistical literature. Given m rankings of n objects the objective is to determine a consensus ranking. The input rankings may contain ties, be incomplete, and may be weighted. Two solution concepts are discussed, the first maximizing the average weighted rank correlation of the solution ranking with the input rankings and the second minimizing the average weighted Kemeny–Snell distance. A new rank correlation coefficient called τ x is presented which is shown to be the unique rank correlation coefficient which is equivalent to the Kemeny‐Snell distance metric. The new rank correlation coefficient is closely related to Kendall's tau but differs from it in the way ties are handled. It will be demonstrated that Kendall's τ b is flawed as a measure of agreement between weak orderings and should no longer be used as a rank correlation coefficient. The use of τ x in the consensus ranking problem provides a more mathematically tractable solution than the Kemeny–Snell distance metric because all the ranking information can be summarized in a single matrix. The methods described in this paper allow analysts to accommodate the fully general consensus ranking problem with weights, ties, and partial inputs. Copyright © 2002 John Wiley &amp; Sons, Ltd.

Dynamic causal modeling in PTSD and its dissociative subtype: Bottom–up versus top–down processing within fear and emotion regulation circuitry
Andrew A. Nicholson, Karl Friston, Peter Zeidman, Sherain Harricharan +4 more
2017· Human Brain Mapping153doi:10.1002/hbm.23748

OBJECTIVE: Posttraumatic stress disorder (PTSD) is associated with decreased top-down emotion modulation from medial prefrontal cortex (mPFC) regions, a pathophysiology accompanied by hyperarousal and hyperactivation of the amygdala. By contrast, PTSD patients with the dissociative subtype (PTSD + DS) often exhibit increased mPFC top-down modulation and decreased amygdala activation associated with emotional detachment and hypoarousal. Crucially, PTSD and PTSD + DS display distinct functional connectivity within the PFC, amygdala complexes, and the periaqueductal gray (PAG), a region related to defensive responses/emotional coping. However, differences in directed connectivity between these regions have not been established in PTSD, PTSD + DS, or controls. METHODS: To examine directed (effective) connectivity among these nodes, as well as group differences, we conducted resting-state stochastic dynamic causal modeling (sDCM) pairwise analyses of coupling between the ventromedial (vm)PFC, the bilateral basolateral and centromedial (CMA) amygdala complexes, and the PAG, in 155 participants (PTSD [n = 62]; PTSD + DS [n = 41]; age-matched healthy trauma-unexposed controls [n = 52]). RESULTS: PTSD was characterized by a pattern of predominant bottom-up connectivity from the amygdala to the vmPFC and from the PAG to the vmPFC and amygdala. Conversely, PTSD + DS exhibited predominant top-down connectivity between all node pairs (from the vmPFC to the amygdala and PAG, and from the amygdala to the PAG). Interestingly, the PTSD + DS group displayed the strongest intrinsic inhibitory connections within the vmPFC. CONCLUSIONS: These results suggest the contrasting symptom profiles of PTSD and its dissociative subtype (hyper- vs. hypo-emotionality, respectively) may be driven by complementary changes in directed connectivity corresponding to bottom-up defensive fear processing versus enhanced top-down regulation. Hum Brain Mapp 38:5551-5561, 2017. © 2017 Wiley Periodicals, Inc.

New results on selection diversity
E.A. Neasmith, Norman C. Beaulieu
1998· IEEE Transactions on Communications147doi:10.1109/26.668745

The performances of selection diversity receiver structures in a slow flat Rayleigh-fading environment are assessed. A number of new and interesting results are obtained. Binary digital signaling using noncoherent frequency-shift keying (NCFSK), differential phase-shift keying (DPSK), coherent phase-shift keying (CPSK), and coherent frequency-shift keying (CFSK) is considered. The traditional analysis (the traditional selection diversity model) of a selection diversity system is based on choosing the branch with the largest signal-to-noise (SNR) power ratio while assuming that the noise power is constant across all branches. However, many practical selection systems choose the branch based on a largest signal-plus-noise (S+N selection) sample of a filter output. This paper comprises accurate analyses of such S+N selection systems. Results show that S+N selection systems perform better than predicted by the traditional selection diversity model. This is because the former includes the statistical nature of the noise, whereas the latter does not. The performance difference between the two models increases as the number of diversity branches increases. For each of DPSK and CPSK, the dual diversity equal gain (EG) combining and S+N selection systems perform identically. For each of NCFSK and CFSK, receiver structures which are equivalent when there is no diversity perform differently in a diversity environment. Certain dual diversity S+N selection systems give the same performances as EG combining or square law combining. The results are contingent upon perfect cophasing for the EG combining. In systems where estimates of the combining carrier phases contain noise, S+N selection outperforms EG combining for dual diversity.

Separation of target rigid body and micro-doppler effects in ISAR imaging
Ljubiša Stanković, Igor Djurović, T. Thayaparan
2006· IEEE Transactions on Aerospace and Electronic Systems140doi:10.1109/taes.2006.314590

Micro-Doppler (m-D) effect is caused by moving parts of the radar target. It can cover rigid parts of a target and degrade the inverse synthetic aperture radar (ISAR) image. Separation of the patterns caused by stationary parts of the target from those caused by moving (rotating or vibrating) parts is the topic of this paper. Two techniques for separation of the rigid part from the rotating parts have been proposed. The first technique is based on time-frequency (TF) representation with sliding window and order statistics techniques. The first step in this technique is recognition of rigid parts in the range/cross-range plane. In the second step, reviewed TF representation and order statistics setup are employed to obtain signals caused by moving parts. The second technique can be applied in the case of very emphatic m-D effect. In the first step the rotating parts are recognized, based on the inverse Radon transform (RT). After masking these patterns, a radar image with the rigid body reflection can be obtained. The proposed methods are illustrated by examples

Injection locking and mode selection in TEA-CO&amp;lt;inf&amp;gt;2&amp;lt;/inf&amp;gt;laser oscillators
J.-L. Lachambre, P. Lavigne, G. Otis, Michael W. Noel
1976· IEEE Journal of Quantum Electronics122doi:10.1109/jqe.1976.1069085

The injection of a master oscillator signal in a high-power TEA-CO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> laser is analyzed and a dynamic model is formulated to represent the interaction. Based on the competition between the injected signal and the spontaneous emission, the model describes the transient evolution of the different field amplitudes and phases together with their effect on the inversion. A study over a wide range of injection levels and detuning frequencies clearly indicates three distinct regions of operation: a spontaneous oscillation zone, a mode-selection zone, and a frequency-locking zone. The main predictions of the model are compared with the results obtained with an experimental injection apparatus that assures adequate control of the TEA laser cavity length and that provides means for measuring the frequency of the output pulse. While the first two zones are directly observed, it is experimentally established that, at injection levels up to 5 W/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , the frequency-locking zone does not exceed, as predicted, the 3-MHz resolution limit of the apparatus.

Algorithms for least-squares linear prediction and maximum entropy spectral analysis—Part I: Theory
I. Barrodale, Ranel E. Erickson
1980· Geophysics121doi:10.1190/1.1441091

Abstract Experience with the maximum entropy spectral analysis (MESA) method suggests that (1) it can produce inaccurate frequency estimates of short sample sinusoidal data, and (2) it sometimes produces calculated values for the filter coefficients that are unduly contaminated by rounding errors. Consequently, in this report we develop an algorithm for solving the underlying least-squares linear prediction (LSLP) problem directly, without forcing a Toeplitz structure on the model. This approach leads to more accurate frequency determination for short sample harmonic processes, and our algorithm is computationally efficient and numerically stable. The algorithm can also be applied to two other versions of the linear prediction problem. A Fortran program is given in Part II.

A Social‐Cognitive Perspective of Terrorism Risk Perception and Individual Response in Canada
Jennifer E. C. Lee, Louise Lemyre
2009· Risk Analysis118doi:10.1111/j.1539-6924.2009.01264.x

The volume of research on terrorism has increased since the events of September 11, 2001. However, efforts to develop a contextualized model incorporating cognitive, social-contextual, and affective factors as predictors of individual responses to this threat have been limited. Therefore, the aim of this study was to evaluate a series of hypotheses drawn from such a model that was generated from a series of interviews with members of the Canadian public. Data of a national survey on perceived chemical, biological, radiological, nuclear, and explosives (CBRNE) terrorism threat and preparedness were analyzed. Results demonstrated that worry and behavioral responses to terrorism, such as individual preparedness, information seeking, and avoidance behaviors, were each a function of cognitive and social-contextual factors. As an affective response, worry about terrorism independently contributed to the prediction of behavioral responses above and beyond cognitive and social-contextual factors, and partially mediated the relationships of some of these factors with behavioral responses. Perceived coping efficacy emerged as the cognitive factor associated with the most favorable response to terrorism. Hence, findings highlight the importance of fostering a sense of coping efficacy to the effectiveness of strategies aimed at improving individual preparedness for terrorism.

Variability of Time to Exhaustion During Submaximal Exercise
Tom M. McLellan, Stephen S. Cheung, Ira Jacobs
1995· Canadian Journal of Applied Physiology117doi:10.1139/h95-003

Exercise time to exhaustion (TE) is commonly used to evaluate the success or failure of such treatments as endurance training programs or nutritional supplements. The present study determined the variability of TE during submaximal exercise at 80% VO2max. Fifteen males performed cycle exercise to exhaustion on five occasions at the same time of day with a minimum of 72 hrs between sessions. There was no difference in TE (0.1 > p > 0.05) among the trials, with values ranging from 14.4 +/- 1.1 min for Test 1 to 18.2 +/- 2.4 min during the final test. Substantial variability in TE over the five trials was observed among subjects with coefficients of variation (CV) ranging from 2.8 to 31.4%. Subjects were divided into two groups using the median CV for TE. For the low CV group (n = 8), TE was significantly increased during Test 3 (14.9 +/- 1.3 min) compared with Test 1 (12.8 +/- 1.0 min) and Test 5 (12.5 +/- 1.2 min). For the high CV group (n = 7), TE was increased during Test 5 (24.7 +/- 3.7 min) compared with the other tests (18.5 +/- 2.2 min). CV for VO2, VE, pH, Pco2, and rectal temperature were less than 5% and did not differ between groups. Post hoc power calculations revealed that if all subjects were considered as one group, sample size would have to increase to 40 to increase the power to 0.8. Due to the variability in TE that may be observed with males of average fitness, it is concluded that TE should not be the only dependent measure used to evaluate treatment effects during submaximal exercise.