Occupational health problems and injuries among Quebec's physical educators

The purpose of this study was to describe the traumatology of teaching physical education (PE) and to document the causes and mechanisms of injuries in this occupation. Our sample was composed of 314 physical educators (PEs) teaching at three school levels (primary school, secondary school and college) who responded to a questionnaire survey. The results showed a 0.55 rate of recent lesion per teacher per year (0.65 for women and 0.51 for men). A total of 37.6% of subjects were affected by a lesion during the last year at work. Subjects with a higher weekly frequency of leisure physical activities or endurance activities (five times and more) were less affected by chronic lesions as well as those who frequently practiced aerobic physical activities. Prevalence of chronic injuries was higher in older teachers. Our results confirm that the rate of lesions in this group of workers is high, and that school level and respondent age may influence the rate of lesion and the characteristics of risk factors. In particular, the effect of ageing and teaching specialization on the incidence of occupational problems in PEs warrants further research. Given the relatively high rate of injuries among PE teachers, we suggest that it is necessary to further explore preventive strategies to reduce occupational risk in these workers. In particular, prophylactic physical activity outside of work may represent such a strategy since PEs more active outside their work have lower chronic injury prevalence. PEs gave long periods of standing the highest rating for movements or positions most likely to cause them occupational injuries. It can thus be suggested to find ways to reduce standing position sustained for long periods.     

Sharing information and building trust through value congruence

This study explores how value congruence contributes to the formation of trust in e-businesses, and how trust and value congruence influence consumers to share personal information. It is hypothesized that the perceived values of organizations regarding moral, social, environmental and political causes can have an effect on the trusting beliefs of e-commerce consumers and their willingness to disclose private personal information. A total of 775 subjects rated their perceived value congruence with organizations, their trusting beliefs, and the types of information they would be willing to disclose. This study finds that value congruence not only plays a role in mediating the trust of consumers for the organizations, but it also has a strong effect on determining their willingness to disclose personal information. In some cases, the influence of value congruence is greater than that of trust, even though trust has been touted in the literature as one of the most important factors in e-commerce. This research expands prior work by using structural equation modeling to test the relative strength of the effect of value congruence on each dimension of trust and the overall trust level, as well as its direct effect on behavioral intentions in terms of information sharing for non-profit and for-profit organizations.

Is Grover’s Algorithm a Quantum Hidden Subgroup Algorithm?

The arguments given in this paper suggest that Grover’s and Shor’s algorithms are more closely related than one might at first expect. Specifically, we show that Grover’s algorithm can be viewed as a quantum algorithm which solves a non-abelian hidden subgroup problem (HSP). But we then go on to show that the standard non-abelian quantum hidden subgroup (QHS) algorithm can not find a solution to this particular HSP. This leaves open the question as to whether or not there is some modification of the standard non-abelian QHS algorithm which is equivalent to Grover’s algorithm.      

Progressive volume rendering of large unstructured grids

We describe a new progressive technique that allows real-time rendering of extremely large tetrahedral meshes. Our approach uses a client-server architecture to incrementally stream portions of the mesh from a server to a client which refines the quality of the approximate rendering until it converges to a full quality rendering. The results of previous steps are re-used in each subsequent refinement, thus leading to an efficient rendering. Our novel approach keeps very little geometry on the client and works by refining a set of rendered images at each step. Our interactive representation of the dataset is efficient, light-weight, and high quality. We present a framework for the exploration of large datasets stored on a remote server with a thin client that is capable of rendering and managing full quality volume visualizations.     

Superfluid3He-B in a realistic thin film. Gap and critical current

We examine³He-B confined to a thin film on a rough substrate with a freestanding upper surface by using quasiclassical techniques. First, the dependence of the gap on surface roughness, film width, and boundary condition formulation is examined in detail for the current-free state. The evaluation is conducted using both the Randomly Rippled Wall and the Thin Dirty Layer surface models in order to compare them. Second, the current bearing state for a submicron film resting on a rough substrate is calculated using the Thin Dirty Layer surface model. Several unusual and previously unreported features appear in both cases. Numerical estimates of the critical current densities are in favorable agreement with corresponding experiments.     

Will virtual education initiatives succeed?

The use of information technology to enhance teaching and learning processes has been practiced for a number of years now. However, the rapid growth in the use of the Internet has led to a new dimension in interactive and collaborative learning anytime and anyplace dynamically. With the explosion of “virtual education initiatives”, the question of the feasibility and success criteria for such projects quickly arises. To address the question in an organized way, we propose a project assessment based on critical success factors. Hence, in this article, we draw on a widely recognized critical success factor framework. We (slightly) adjust the framework to fit the special characteristics of virtual education initiatives, and apply to one case study, namely the virtual education initiative at the Faculty of Business at the City University of Hong Kong. The results suggest that the past success of the case is due to the adherence to the large majority of critical success factors. However, it also outlines some areas of concern. The paper concludes with a discussion on the strength and limitations of virtual learning environment as well as future directions. This revised version was published online in July 2006 with corrections to the Cover Date.     

A note on the complexity of program evaluation

A simple problem concerning evaluation of programs is shown to be nonelementary recursive. The problem is the following: Given an input-free programP (i.e. all variables are initially 0) without nested loops using only instructions of the formx ← 1, x ← x + y, \(x \leftarrow x\dot - y\) ,do x... end, doesP output 0? This problem has time complexity \(2^{2^{ {\mathinner{\mkern2mu\raise1pt\hbox{.}\mkern2mu \raise4pt\hbox{.}\mkern2mu\raise7pt\hbox{.}\mkern1mu}} ^2 } } \) }cn-levels for some constantc. Other results are presented which show how the complexity of the 0-evaluation problem changes when the nonlooping instructions are varied. For example, it is shown that 0-evaluation is PSPACE-complete even for the case when the nonlooping instructions are onlyx ← x + 1,if x = 0then y ←y \(y \leftarrow y\dot - 1\) .     

On restricted one-counter machines

Let be the class of real-time nondeterministic one-counter machines whose counters make at mostone reversal. Let ₁ (respectively, ₂) be the subclass consisting of machines whose only nondeterministic move is in the choice of when to reverse the counter (respectively, when to start using the counter). ₁ and ₂ are among the simplest known classes of machines for which the universe problem has been shown undecidable. (The universe problem for a class of machines is the problem of deciding if an arbitrary machine in the class accepts all its inputs.) Here, we show that the classes of languages accepted by machines in ₁ and ₂ are incomparable. Moreover, the union of the language classes is properly contained in the class defined by . We also, briefly, look at the closure properties of these machines.This research was supported in part by NSF Grant MCS78-01736.     

Re-engineering the Engineering Change Management process for a drawing-less environment

Currently, 3D models and 2D drawings are the main basic elements that together form and carry the product definition throughout the product lifecycle. With the advent of the Digital Product Definition trend, industries have been interested in adopting a Model-based Definition (MBD) approach that enables the integration of drawing annotations directly onto a 3D model, thereby minimizing the need to generate engineering drawings. This drawing-less environment requires a way to adequately carry the product definition throughout a product's lifecycle while supporting all of the downstream users’ specific needs. The objective of this article is to present a solution to carry the Engineering Change Management (ECM) process in a drawing-less environment. Therefore, based on ECM process requirements from two Canadian aerospace companies, we propose an MBD dataset which consists of an MBD model and a distribution file. The proposed MBD dataset is evaluated and the MBD-driven ECM process is outlined.     

Impairment in long-term retention but not short-term performance on a water maze reversal task following hippocampal or mediodorsal striatal n-methyl-d-aspartate receptor blockade.

Male Long-Evans rats were injected with 32 ng/μl of the N-methyl-D-aspartate (NMDA) receptor antagonist 3-(2-carboxypiperazin-4-yl) propyl-1-phosphonic acid (CPP) or vehicle and trained to locate a hidden platform in a different location (reversal training) than used on the initial 4 days of training. Rats treated with vehicle or CPP into the dorsal hippocampus, basolateral amygdala, or mediodorsal striatum had similar latencies to locate the platform on the reversal day. Rats infused with CPP into the dorsal hippocampus or mediodorsal striatum failed to search preferentially in the novel location during a 24-hr, drug-free retention test, whereas all other groups searched preferentially in this location. Therefore, blocking dorsal hippocampal or mediodorsal striatal NMDA receptors selectively blocked long-term spatial retention without producing short-term performance deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)