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Optimum positioning for anteroposterior pelvis radiography: A literature reviewAlzyoud, K., Hogg, P., Snaith, Beverly, Flintham, K., England, A. 15 May 2018 (has links)
Yes / Pelvic radiography is used for the identification of hip joint changes, including pathologies such as osteoarthritis. Several studies have recommended that the position for this radiological procedure should be standing, not supine, to reflect the functional appearances of the hip joint. The aim of this review was to evaluate pelvis radiography positioning with respect to the image appearances and information provided for clinical decision-making. Aside from this, potential recommendations to the radiographic technique for an erect pelvis projection will be considered.
Method:
A literature search was performed using databases/ systems (ScienceDirect, Web of Science, PubMed, and MEDLINE). Only articles written in English were included.
Results:
Twenty-five articles were identified. Findings from the review describe the effect of repositioning from supine to erect on a series of specific hip measurements. These include pelvic tilt, joint space width, and the acetabular component.
Conclusion:
Evidence within the literature illustrates that in several studies, there were differences when repositioning from supine to standing for a number of pelvic metrics. Standing positioning is promoted by some authors since this may facilitate the early diagnosis of hip joint pathology and assist in the planning of surgical interventions. Literature is very limited on how to optimally perform erect pelvis radiography, and this should be an area for future research.
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Facteurs influencing haptic shape perceptionToderita, Iuliana 12 1900 (has links)
Le but de cette étude était de déterminer la contribution de plusieurs facteurs (le design de
la tâche, l’orientation d’angle, la position de la tête et du regard) sur la capacité des sujets à
percevoir les différences de formes bidimensionnelles (2-D) en utilisant le toucher haptique.
Deux séries d'expériences (n = 12 chacune) ont été effectuées. Dans tous les cas, les angles ont
été explorés avec l'index du bras tendu. La première expérience a démontré que le seuil de
discrimination des angles 2-D a été nettement plus élevé, 7,4°, que le seuil de catégorisation des
angles 2-D, 3,9°. Ce résultat étend les travaux précédents, en montrant que la différence est
présente dans les mêmes sujets testés dans des conditions identiques (connaissance des résultats,
conditions d'essai visuel, l’orientation d’angle). Les résultats ont également montré que l'angle de
catégorisation ne varie pas en fonction de l'orientation des angles dans l'espace (oblique,
verticale). Étant donné que les angles présentés étaient tous distribués autour de 90°, ce qui peut
être un cas particulier comme dans la vision, cette constatation doit être étendue à différentes
gammes d'angles. Le seuil plus élevé dans la tâche de discrimination reflète probablement une
exigence cognitive accrue de cette tâche en demandant aux sujets de mémoriser temporairement
une représentation mentale du premier angle exploré et de la comparer avec le deuxième angle
exploré.
La deuxième expérience représente la suite logique d’une expérience antérieure dans
laquelle on a constaté que le seuil de catégorisation est modifié avec la direction du regard, mais
pas avec la position de la tête quand les angles (non visibles) sont explorés en position
excentrique, 60° à la droite de la ligne médiane. Cette expérience a testé l'hypothèse que
l'augmentation du seuil, quand le regard est dirigé vers l'extrême droite, pourrait refléter une
action de l'attention spatiale. Les sujets ont exploré les angles situés à droite de la ligne médiane,
variant systématiquement la direction du regard (loin ou vers l’angle) de même que
l'emplacement d'angle (30° et 60° vers la droite). Les seuils de catégorisation n’ont démontré
aucun changement parmi les conditions testées, bien que le biais (point d'égalité subjective) ait
été modifié (décalage aux valeurs inférieurs à 90°). Puisque notre test avec le regard fixé à
l’extrême droite (loin) n'a eu aucun effet sur le seuil, nous proposons que le facteur clé
contribuant à l'augmentation du seuil vu précédemment (tête tout droit/regard à droite) doit être
cette combinaison particulière de la tête/regard/angles et non l’attention spatiale. / The purpose was to determine the contribution of several factors (design of the task,
angle orientation, head position and gaze) to the ability of subjects to perceive differences in twodimensional
(2-D) shape using haptic touch. Two series of experiments (n=12 each) were carried
out. In all cases the angles were explored with the index finger of the outstretched arm. The first
experiment showed that the mean threshold for 2-D angle discrimination was significantly higher,
7.4°, than for 2-D angle categorization, 3.9°. This result extended previous work, by showing that
the difference is present in the same subjects tested under identical conditions (knowledge of
results, visual test conditions, angle orientation). The results also showed that angle
categorization did not vary as a function of the orientation of the angles in space (oblique,
upright). Given that the angles presented were all distributed around 90°, and that this may be a
special case as in vision, this finding needs to be extended to different ranges of angles. The
higher threshold with angle discrimination likely reflects the increased cognitive demands of this
task which required subjects to temporarily store a mental representation of the first angle
scanned, and to compare this to the second scanned angle.
The second experiment followed up on observations that categorization thresholds are
modified with gaze direction but not head position when the unseen angles are explored in an
eccentric position, 60° to the right of midline. This experiment tested the hypothesis that the
increased threshold when gaze was directed to the far right might reflect an action of spatial
attention. Subjects explored angles located to the right of midline, systematically varying the
direction of gaze (away from or to the angles) along with angle location (30° and 60° to the right).
Categorization thresholds showed no change across the conditions tested, although bias (point of
subjective equality) was changed (shift to lower angle values). Since our testing with far right
gaze (away) had no effect on threshold, we suggest that the key factor contributing to the
increased threshold seen previously (head forward/gaze right) must have been this particular
combination of head/gaze/angles used and not spatial attention.
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Le secteur de l’aviation et les règles de concurrence de l’Union européenne : étude des comportements et des rapprochements d’entreprises / The aviation sector and the European Union's competition rules : Study on conducts and rapprochements of undertakingsVougioukas, Dimitrios 10 February 2012 (has links)
L’application des règles de concurrence de l’Union européenne au secteur de l’aviation présente un caractère spécial. Les rapprochements des compagnies aériennes sous formes d’alliances ou concentrations sont à première vue indispensables, afin de garantir leur viabilité et mieux desservir les besoins des voyageurs. La pression concurrentielle exercée par les différents moyens de transports et la globalisation des échanges conduisent vers cette voie. Or, la consolidation du marché aérien peut avoir des conséquences néfastes au détriment des consommateurs. Structure oligopolistique, organisation des gros opérateurs en réseaux (hub-and-spoke system), insuffisance des infrastructures, coûts énormes d’exploitation ainsi que protectionnisme au niveau international, constituent des barrières considérables à l’entrée de nouveaux concurrents et peuvent conduire à des pratiques abusives. La transparence tarifaire et les accords de coopération peuvent favoriser les cartels entre transporteurs aériens. La Commission évalue la position des parties et les risques à la concurrence sur des liaisons déterminées (paires de villes). Cette méthode de délimitation du marché pertinent au transport aérien suscite une polémique de la part notamment des compagnies aériennes qui soutiennent une approche fondée sur la concurrence entre réseaux. Ce débat, montre l’évolution du secteur de l’aviation et la nécessité de prendre toujours en compte les nouvelles données. Le maintien d’une concurrence efficace au secteur de l’aviation n’est pas un objectif en soi, mais un instrument de la politique européenne pour la création du « ciel unique européen ». L’intervention des autorités de l’Union européenne au secteur de l’aviation ne se limite pas à une application rigoureuse des règles de concurrence mais vise à éliminer préalablement les phénomènes anticoncurrentiels par l’adoption d’un cadre législatif. / The application of European Union’s competition rules to the aviation sector presents a special character. The rapprochement of air companies either by the formation of alliances or mergers seem to be necessary. Indeed, it can guarantee the existence of a company as well as it serves the needs of travellers. The competitive pressure exercised by the different existing means of transportation and the globalisation of exchanges lead to this behaviour. But this consolidation of the air market can have harmful consequences for consumers. Oligopolistic structures, the hub-and-spoke system, insufficiency of infrastructures, enormous costs of exploitation along with protectionism at an international level, constitute considerable barriers for new competitors and could lead to abusive practices. Tariff transparency and cooperative agreements can furtherer cartels in between air transporters. The Commission assesses the position of the parties and competitive risks on specific routes (city pairs). This method of delimitation of the market for air transport has created a polemic, especially from the airline companies supporting an approach based on competition between networks. This debate shows the evolution of the aviation sector and the necessity of always taking into consideration new data. The upholding of an efficient competition system within the aviation sector is not an objective in itself, but means of European politic for the creation of a “Single European Sky”. The intervention of European authorities within the aviation sector is not limited to a rigorous application of competition rules but aims first at eliminating anticompetitive phenomenon by adopting a legislative framework.
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Facteurs influencing haptic shape perceptionToderita, Iuliana 12 1900 (has links)
Le but de cette étude était de déterminer la contribution de plusieurs facteurs (le design de
la tâche, l’orientation d’angle, la position de la tête et du regard) sur la capacité des sujets à
percevoir les différences de formes bidimensionnelles (2-D) en utilisant le toucher haptique.
Deux séries d'expériences (n = 12 chacune) ont été effectuées. Dans tous les cas, les angles ont
été explorés avec l'index du bras tendu. La première expérience a démontré que le seuil de
discrimination des angles 2-D a été nettement plus élevé, 7,4°, que le seuil de catégorisation des
angles 2-D, 3,9°. Ce résultat étend les travaux précédents, en montrant que la différence est
présente dans les mêmes sujets testés dans des conditions identiques (connaissance des résultats,
conditions d'essai visuel, l’orientation d’angle). Les résultats ont également montré que l'angle de
catégorisation ne varie pas en fonction de l'orientation des angles dans l'espace (oblique,
verticale). Étant donné que les angles présentés étaient tous distribués autour de 90°, ce qui peut
être un cas particulier comme dans la vision, cette constatation doit être étendue à différentes
gammes d'angles. Le seuil plus élevé dans la tâche de discrimination reflète probablement une
exigence cognitive accrue de cette tâche en demandant aux sujets de mémoriser temporairement
une représentation mentale du premier angle exploré et de la comparer avec le deuxième angle
exploré.
La deuxième expérience représente la suite logique d’une expérience antérieure dans
laquelle on a constaté que le seuil de catégorisation est modifié avec la direction du regard, mais
pas avec la position de la tête quand les angles (non visibles) sont explorés en position
excentrique, 60° à la droite de la ligne médiane. Cette expérience a testé l'hypothèse que
l'augmentation du seuil, quand le regard est dirigé vers l'extrême droite, pourrait refléter une
action de l'attention spatiale. Les sujets ont exploré les angles situés à droite de la ligne médiane,
variant systématiquement la direction du regard (loin ou vers l’angle) de même que
l'emplacement d'angle (30° et 60° vers la droite). Les seuils de catégorisation n’ont démontré
aucun changement parmi les conditions testées, bien que le biais (point d'égalité subjective) ait
été modifié (décalage aux valeurs inférieurs à 90°). Puisque notre test avec le regard fixé à
l’extrême droite (loin) n'a eu aucun effet sur le seuil, nous proposons que le facteur clé
contribuant à l'augmentation du seuil vu précédemment (tête tout droit/regard à droite) doit être
cette combinaison particulière de la tête/regard/angles et non l’attention spatiale. / The purpose was to determine the contribution of several factors (design of the task,
angle orientation, head position and gaze) to the ability of subjects to perceive differences in twodimensional
(2-D) shape using haptic touch. Two series of experiments (n=12 each) were carried
out. In all cases the angles were explored with the index finger of the outstretched arm. The first
experiment showed that the mean threshold for 2-D angle discrimination was significantly higher,
7.4°, than for 2-D angle categorization, 3.9°. This result extended previous work, by showing that
the difference is present in the same subjects tested under identical conditions (knowledge of
results, visual test conditions, angle orientation). The results also showed that angle
categorization did not vary as a function of the orientation of the angles in space (oblique,
upright). Given that the angles presented were all distributed around 90°, and that this may be a
special case as in vision, this finding needs to be extended to different ranges of angles. The
higher threshold with angle discrimination likely reflects the increased cognitive demands of this
task which required subjects to temporarily store a mental representation of the first angle
scanned, and to compare this to the second scanned angle.
The second experiment followed up on observations that categorization thresholds are
modified with gaze direction but not head position when the unseen angles are explored in an
eccentric position, 60° to the right of midline. This experiment tested the hypothesis that the
increased threshold when gaze was directed to the far right might reflect an action of spatial
attention. Subjects explored angles located to the right of midline, systematically varying the
direction of gaze (away from or to the angles) along with angle location (30° and 60° to the right).
Categorization thresholds showed no change across the conditions tested, although bias (point of
subjective equality) was changed (shift to lower angle values). Since our testing with far right
gaze (away) had no effect on threshold, we suggest that the key factor contributing to the
increased threshold seen previously (head forward/gaze right) must have been this particular
combination of head/gaze/angles used and not spatial attention.
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Zvláštní odpovědnost podniku v dominantním postavení / Special liability of businesses in dominant positionČechráková, Iva January 2016 (has links)
Title: Special responsibility of undertaking in dominant position Author: Iva Čechráková Department: Department of Business Law Supervisor: JUDr. Daniel Patěk, Ph.D Abstract: This thesis deals with the doctrine of special responsibility of the dominant undertaking and related issues. The special responsibility of the dominant undertaking is the obligation not to allow its conduct to impair genuine undistorted competition on the common market. The doctrine of the special responsibility is tied to the prohibition on abuse of such position. One concept could not be assessed without the other, because the concept of special responsibility of the dominant undertaking is a fundamental principle for the application of the prohibition on abuse of such position. Based on that it is necessary to describe in this thesis the prohibition on abuse of dominant position together with selected prohibited practices, in which the special responsibility of the dominant undertaking is reflected. This responsibility presupposes a higher standard of vigilance reflected in the conduct of such an undertaking, because an undertaking in dominant position on the relevant market could not take all actions that the other undertakings lacking such market power could do. The question of the superdominant undertakings and the scope of...
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Upplevd Yrkesstatus och Stress : Vad skapar upplevd yrkesstatus och har yrkesstatus samband med stress?Westberg, Nathalie, Persson, Sara January 2015 (has links)
This study examines subjective occupational status and what factors influence and indicate subjective occupational status among employees in the municipal sector. The study also investigates if subjective occupational status has any significant connections with stress and worrying. The aim of this study is to examine if income, education, age, gender and length of employment has any significant effect on the subjective occupational status. We also aim to investigate if subjective occupational status affects the respondent’s levels of stress and worry. The material for the study was collected via a questionnaire with 268 respondents. The survey was done via the internet and sent out to the respondents via e-mail. We are utilizing the reference group theory in our analysis of the material. Reference group theory states that subjective social position is created by social comparison. Individuals tend to base their position in the social hierarchy and compare themselves with individuals who are similar to them. This leads to that many people places themselves as average. The results of the study show that it is only income which is affecting the subjective occupational status. We also found that subjective occupational status does not have any connections with stress apart from causing the respondents some worry over not having time to complete their work assignments.
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BASELINE COMMUNICATIONS SYSTEM FOR A SMALL SATELLITEOrozco, Gina 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The NMSUSat is part of the AFRL/NASA University Nanosatellite program. The constellation will
consist of a main microsatellite that will have a command link from ground and a telemetry link to
ground while a picosatellite will act as a sensor reporting data to the microsatellite. Innovative
command and data handling will be incorporated at low cost and greater accessibility. In this paper
we present the necessary communications and control architecture for the space segment and the
ground segment of the nanosatellite.
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The relative effect of manipulation and core rehabilitation in the treatment of acute mechanical low back pain in sedentary patientsHiggs, Renee Joy January 2007 (has links)
Dissertation submitted in partial compliance with the requirements for the Master’s
Degree in Technology: Chiropractic, Durban University of Technology, 2007. / The aim of this research was to investigate the relative effectiveness of
manipulation versus core rehabilitation in the treatment of acute mechanical low
back pain in sedentary patients.
Recent research has found that dysfunction of the primary core stabiliser
muscles is linked with an increasing number of the general population suffering
from low back pain; this is thought to be due to the fact that people in general are
living more sedentary lifestyles.
The Aims and Objectives of this study were to determine the relative effect of
manipulation and core rehabilitation in sedentary patients suffering from acute
mechanical low back pain in terms of subjective findings, objective findings and
to determine any correlations between these findings
Thirty-two participants, with acute low back pain participated in the study. They
received treatment over a period of three weeks, two treatments in the first week,
two treatments in the second week and a follow up seven days later. Group A
received a spinal manipulation while Group B received core rehabilitation
exercises. Readings were taken at three time points, namely visit one, three and
five before the treatment, they included the following readings: Numerical Pain Rating Scale, Algometer, Roland Morris Low Back Pain and Disability
Questionnaire, Biofeedback Stabiliser and the Surface EMG.
The results showed that there was no differential (p<0.05) treatment effect
between the two Groups, and that both Groups showed a clinical improvement in
their low back pain.
In conclusion, it appears that even though both these treatment protocols have
very different mechanisms of action, both can be effective treatment protocols
and that core rehabilitation exercises when properly performed are as effective
as manipulation in the treatment of acute low back pain.
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COMBINING TECHNOLOGIES TO FOSTER IMPROVED TSPI ACCURACY AND INCREASE SHARING OF THE FREQUENCY SPECTRUMSwitzer, Earl R., Wrin, John, Huynh, James 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The loss of radio frequency (RF) spectrum for use in testing has steadily increased the likelihood that users of the few remaining frequencies available to test ranges will experience scheduling conflicts and interference with nontest users. A gradual increase in the base of test customers engaged in scientific, military, and commercial R&D, point toward a near term situation in which more test customers will be competing for fewer frequencies. The test ranges, often operating in close geographical proximity with other communications-intensive functions as well as with each other, will also encounter increasing out-of-band and adjacent-channel interference. This projected growth of R&Drelated testing constrained to operate in a diminished RF spectrum (and a more confined test space), will undoubtedly stimulate the development of new products that make more efficient use of the RF spectrum. This paper describes one such innovative approach to spectrum sharing. The authors assess the operational need for an affordable miniaturized avionics instrument package based on a C-band radar transponder integrated with a Global Positioning System/Inertial Measurement Unit (GPS/IMU). The proposed approach would make use of frequencies already allocated for use by existing C-band aeronautical transponders. It would augment the format of the transponder output data to include the vehicle position obtained from an onboard GPS/IMU. Existing range instrumentation radars, such as the venerable AN/FPS-16, could be modified with lowcost upgrade kits to provide uniformly higher accuracy over the entire transponder coverage range.
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MULTIPLE TARGET INSTRUMENTATION RADARS FOR MILITARY TEST AND EVALUATIONMILWAY, WILLIAM B. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1985 / Riviera Hotel, Las Vegas, Nevada / Military aerospace test ranges are increasingly being called upon to conduct missions utilizing large numbers of participating units, or targets. Precision, position and trajectory data must be recorded on all participants. In addition, weapon/target engagements must be scored and real-time range safety considerations must be accommodated. This requires precision metric data be available in real-time on all participating targets. One solution to these problems, is utilization of multiple target tracking radars which incorporate electronic beam steering to quickly move from one target to another in sequence. This paper briefly recounts the history of range instrumentation radars, points out some of the advantages of using multi-target radars, and highlights the specifications and design of a multiple target instrumentation radar now being acquired by the U.S. Army for use at White Sands Missile Range and the Kwajalein Missile Range.
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