Les déterminants des politiques provinciales au Canada : Une synthèse des études comparatives

Cet article est un bilan des écrits ayant pour objet l’analyse comparative des politiques publiques dans les dix provinces canadiennes. Le bilan est fait en deux temps. D’abord, nous caractérisons le choix des politiques gouvernementales étudiées (la variable dépendante) en fonction de quatre critères : le secteur d’intervention, le point de vue, le type d’observation et la forme de l’activité gouvernementale. Ensuite, nous regardons plus attentivement le choix des facteurs explicatifs (les variables indépendantes) en nous attardant à la pertinence des arguments donnés par les écoles de la convergence et du « Politics Matters ».This article is a review of the studies on provincial public policies in a comparative perspective. We first caracterise the choice of government policies (the dependent variable) using four criteria: the sector of intervention, the point of view, the type of observation, and the form of government activity. Then we direct our attention to the choice of explanatory factors (the independent variables) looking at the relevance of the arguments presented by two approaches: the "Convergence Approach" and the "Politics Matters Approach"

Precision and scaling in morphogen gradient read-out

Morphogen gradients infer cell fate as a function of cellular position. Experiments in Drosophila embryos have shown that the Bicoid (Bcd) gradient is precise and exhibits some degree of scaling. We present experimental results on the precision of Bcd target genes for embryos with a single, double or quadruple dose of bicoid demonstrating that precision is highest at mid-embryo and position dependent, rather than gene dependent. This confirms that the major contribution to precision is achieved already at the Bcd gradient formation. Modeling this dynamic process, we investigate precision for inter-embryo fluctuations in different parameters affecting gradient formation. Within our modeling framework, the observed precision can only be achieved by a transient Bcd profile. Studying different extensions of our modeling framework reveals that scaling is generally position dependent and decreases toward the posterior pole. Our measurements confirm this trend, indicating almost perfect scaling except for anterior most expression domains, which overcompensate fluctuations in embryo length

GPS for Marine Navigation and Hydrography

Current marine navigation and shipbome surveying accuracy requirements are reviewed. The technical characteristics of GPS are summarized and its single point positioning performance is given and compared with the above requirements. A detailed description and analysis of the three types of observables possible with GPS, namely code, carrier and Doppler frequency measurements, are presented. The following error sources are discussed: cycle slips, Selective Availability, ionospheric and tropospheric effects and multipath. A description of the various receiver measuring techniques currently available, namely C/A code LI, L2 squaring, L2 codeless, P codeless and P code, is given, together with advantages and disadvantages for marine positioning. The single and double differenced observables used in differential GPS (DGPS) mode are analysed in terms of real time versus postmission suitability. The latest techniques for quasi-instantaneous ambiguity resolution such as wide and extra wide-laning are discussed in terms of receiver requirements and operational procedures. An attempt is made at providing DGPS kinematic accuracy estimates for various cases with and without Selective Availability. Trends and prospects are forecast in the following five areas: system enhancements, user equipment, observable types and modelling, marine applications and GPS-related services

EFFECT OF FATIGUE ON DYNAMIC BALANCE AFTER MAXIMUM INTENSITY CROSS-COUNTRY SKIING

Cross-country skiing stresses most of the joints, muscles and tendons in the body giving an overall workout. Skiing requires aerobic and anaerobic power, muscular strength and a variety of complex motor abilities including reaction time, agility, balance, coordination and attention demands (Emily & Arthur, 1989). Muscular fatigue is a key factor which can influence performance via impaired joint proprioception and postural control. Fatigue alters the force generation capacity of the muscle and ultimately leads to task failure (Mahyar et al, 2007). Injury risk increases as time duration of the skiing increases (Smith, Matheson & Meeuwisse, 1996). The maintenance of body posture and balance is an essential requirement for performance of daily tasks and sporting activities. Thus fatigue could affect a skier’s performance through an effect on balance. Fast starts at the beginning of races and short intense efforts required for ascending hills could result in periods of fatigue that could affect balance and performance. Hence fatigue may either result in injury or affect the finish time of the skiers. The main purpose of this study was to evaluate how dynamic balance of the skiers can be influenced by fatigue states following maximum exercis

Does the Decriminalization of Prostitution Reduce Rape and Sexually Transmitted Disease? A Review of Cunningham and Shah Findings

In 2013, research findings by Cunningham and Shah claimed that rape and sexually transmitted diseases were reduced by decriminalized prostitution in Rhode Island. The original unpublished claims have received wide media coverage which have gone unexamined. This review finds errors in their analyses. One error is the date when prostitution was decriminalized in Rhode Island. Cunningham and Shah claim that prostitution was decriminalized in 2003. Our analysis finds the date of decriminalization of prostitution was 1980. The change in the start date of decriminalization significantly alters the analysis and the findings. Another error results from Cunningham and Shah using an outlier data point to define a period of analysis. The results of this review call into question the claims that the decriminalization of prostitution reduced rape and sexually transmitted disease

Use of a Multi-Reference GPS Station Network for Precise 3D Positioning in Constricted Waterways

Numerous coastal and inland marine operations, including navigation in shallow constricted waterways require time-consuming and expensive maintenance that includes frequent precise multi-beam hydrographic surveys and dredging operations. In addition, environmental and safety concerns lead to the establishment of stringent regulations regarding the minimum under keel clearance for commercial shipping operations. The clearance is partly a function of the navigation channel charting accuracy and the ability to determine the instantaneous water level in real time. The use of real-time kinematic (RTK) GPS to provide a three-dimensional accuracy of better than 10 cm has the potential to improve the effectiveness of channel maintenance and commercial navigation. In order for RTK GPS to yield such a high level of accuracy, carrier phase observables must be used. One of the most important limitations is the requirement for short distances between the ship and shore-based fixed reference stations. With the current GPS capability, the distance should be kept to less than 15 to 20 km to assure a continuous service. Establishing reference stations with such a high density is time-consuming, logistically difficult and results in high maintaining cost and operational reliability issues. In this paper a method to substantially reduce the number of reference stations is investigated through field trials conducted along the St. Lawrence Seaway, Canada, in 1998 and 1999. The proximity of the trials to a solar maximum resulted in a very high level of atmospheric activity and provided an opportunity to examine the advantages and limitations of both the conventional and multi-reference station RTK methods under such conditions. The results of the trials show that the new approach results in a substantial improvement of up to 60%

Beyond inverse Ising model: structure of the analytical solution for a class of inverse problems

I consider the problem of deriving couplings of a statistical model from measured correlations, a task which generalizes the well-known inverse Ising problem. After reminding that such problem can be mapped on the one of expressing the entropy of a system as a function of its corresponding observables, I show the conditions under which this can be done without resorting to iterative algorithms. I find that inverse problems are local (the inverse Fisher information is sparse) whenever the corresponding models have a factorized form, and the entropy can be split in a sum of small cluster contributions. I illustrate these ideas through two examples (the Ising model on a tree and the one-dimensional periodic chain with arbitrary order interaction) and support the results with numerical simulations. The extension of these methods to more general scenarios is finally discussed.Comment: 15 pages, 6 figure