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Evaluation of different centrifugation settings using BD Microtainer® tubesMolin, Elin January 2016 (has links)
In order to keep the turnaround time it is desirable to have few centrifugal programs and be able to centrifuge microtainer tubes together with vacutainer tubes. BD has launched a new type of microtainer tube that got a lower g-force than the older one on the same centrifugation program. The aims was to compare this program and three other, more powerful, programs and compare the impact on some common analytes and serum indices, especially on hemolysis. Three test parts was performed using venous samples taken from healthy individuals, 1) transfer of whole blood from serum tube to microtainer tubes, a clinical chemistry analysis; 2) whole blood from plasma tube to microtainer tubes, a clinical chemistry analysis and 3) whole blood from plasma tube to microtainer tubes for platelet count analysis. All tubes were examined for gel formation. The result showed a significant variance between some settings for some analytes but foremost at 899g and at 2000g, both in 10 min. The platelet count was below the threshold limit at 2000g. No tube had insufficient formation of the gel. The setting of 2000g was found suitable for microtainer tubes. These results correspond with the recommended settings from BD. Further studies are needed with more analytes and test subjects and a simulated transport time for plasma, because of the increased risk for hemolysis, to confirm if the same setting can be used for microtainer tubes (899g) as for the older microtainer tube and vacutainer tube (1300g).
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The impact of psychological skills and mindfulness training on the psychological well-beingof undergraduate music studentsSteyn, Margaretha Helena January 2013 (has links)
Extensive research on the psychological benefits of psychological skills training in sport has
been conducted in Sport Psychology, with unambiguous positive results. However,
psychological skills training has not yet been fully applied in the Psychology of Music.
Mindfulness training, and specifically the mindfulness, acceptance and commitment (MAC)
approach, has been applied in sport, but thus far no MAC intervention on musicians has been
published. The combination of Psychological Skills Training (PST) and mindfulness (the MAC
approach) training is more rare and has not yet been used in music studies. The configuration of
mindfulness (MAC) and PST has been applied in a sport setting, but has never been tested in a
proper intervention programme for music students. This study fills this gap.
The primary aim of this research was to implement and evaluate the effect of PST, in
combination with mindfulness, on undergraduate music students. The second aim was to
determine whether the intervention programme had an impact on the students’ psychological
well-being and the management of music performance anxiety. The third aim was to evaluate
whether the students’ psychological skills and mindfulness have improved. The fourth aim was
to determine whether the combination of PST and mindfulness training was successful. The fifth
aim was to evaluate whether the cross-over from Sport Psychology to the Psychology of Music
in terms of the knowledge base, intervention PST protocols and psychometric measuring
instruments was meaningful. The sixth aim was to determine whether the correlations between
the psychological constructs (subscales) of the pre-intervention test measurements on all the
respondents were meaningful. A convenience sample of 36 undergraduate music students from the Department of Music at the
University of Pretoria was selected. The students were asked to participate voluntarily. The
experimental group consisted of 21 students, and the remaining 15 students formed the control
group. A quasi-experimental design was implemented in this research to address problems that might
occur because of the voluntary selection method employed. Voluntary participation was adopted
to ensure that the participants were fully engaged in and committed to this study. The aspects of
motivation and commitment were essential prerequisites for this research to be successful,
because full commitment and maximum attendance of the intervention sessions were crucial to
be able to determine the impact of this intervention programme.
The results indicated a significant improvement in positive relationships with others within the
experimental group, as measured by Ryff’s Psychological Well-being Scale. Pre- and postintervention
test results within the experimental group indicated a statistically significant
improvement in all three subscales of the Competitive State Anxiety Inventory-2 (cognitive state
anxiety, somatic state anxiety and self-confidence). A statistically significant improvement on
five of the seven subscales of Bull’s Mental Skills Questionnaire (self-confidence, anxiety and
worry management, concentration ability, relaxation ability and levels of motivation) were
reported, and on the Five Facet Mindfulness Questionnaire, the subscales of “describe” items
and “non-judge” items improved significantly from the pre-intervention test to the postintervention
test in the experimental group. Interestingly, the growth mindset within the
experimental group also increased significantly, while the fixed mindset decreased significantly.
This significant positive increase in the scores of the experimental group might be an indication
that the intervention programme had a moderately significant impact on important psychological
dimensions of the participating undergraduate music students. / Dissertation (MA)--University of Pretoria, 2013. / gm2014 / Psychology / unrestricted
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Návrh zvýšení úrovně vyspělosti procesů tvorby ASW dle CMMI ve vybrané IT společnosti / Proposal to increase the maturity level of processes developing ASW in the IT companyKastner, Vojtěch January 2012 (has links)
The topic of the thesis is to analyze processes of the IT company developing tailored solution delivered as a project. Based on analyze the recommendation for more effective processes will be provided. Analyze of processes comply with CMMI standard with use of a PST (PIID and SCAMPI Tool) tool from Dr. Ralf Kneuper. The work describes CMMI standard and its use in process evaluation, an example is shown by using the PST tool in evaluation of processes particular IT company. There are proposed recommendations for improvement and process changes according the results of the process evaluation at the end of work. The part of work is introduction of the PST tool with Czech translation of selected process areas corresponding to the maturity level of processes that the analysis is focused.
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Performance development of sport scientists : a Mindfulness-Acceptance-Commitment (MAC) approachMaré, Rozanne January 2016 (has links)
This research study took place at the High Performance Centre (hpc) at the University of Pretoria (UP) in South Africa (SA). The sport psychologists/sports counselors at the hpc mainly deliver performance development services to the athletes. The sport psychology services at the hpc are conducted to the athletes via the Psychological Skills Training (PST) approach and Mindfulness-Acceptance-Commitment (MAC) approach. These two approaches are individualistic in nature and the aim of my study was to move away from a more traditional individualistic perspective to an ecological perspective that takes into consideration other role players such as sport scientists. This was achieved by developing a sport science specific MAC programme for the sport scientists, which was facilitated through experiential learning. The goal of the MAC programme was to explore the sport scientists’ experiences with reference to what they discovered and how they applied their learning. Eight in depth, semi-structured interviews were conducted with four sport scientists at the hpc after their participation in the programme. Interpretive Phenomenological Analysis (IPA) was used to analyse the semi-structured interviews. The findings were mainly related to difficulties and advantages that the sport scientists experienced when they applied the MAC principles. / Dissertation (MA)--University of Pretoria, 2016. / Psychology / MA / Unrestricted
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Les effets de la privation de sommeil dans l'orientation spatialeBeaulieu, Isabelle 06 1900 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal. / La privation de sommeil post-apprentissage cause des déficits lors du rappel de certaines tâches chez l'humain et chez le rat. Néanmoins, peu d'études se sont penchées sur les effets d'une privation de sommeil totale ou sélective précédant l'apprentissage d'une tâche spatiale chez l'humain et le rat. Le présente étude comporte deux volets expérimentaux. Dans un premier temps, nous avons évalué les effets d'une brève privation de sommeil paradoxal (SP) chez le rat sur deux types de tâche spatiale : le labyrinthe aquatique de Morris (mémoire de référence) et une tâche d'alternance différée dans un labyrinthe aquatique (mémoire de travail). La privation de SP a été menée à l'aide de la méthode de la petite plate-forme; des enregistrements de sommeil ont été recueillis au cours de cette période. Dans un deuxième temps, nous avons évalué les effets d'une privation de sommeil totale (PST) sur l'orientation spatiale chez l'humain à l'aide d'un labyrinthe de dimension humaine. Les sujets ont été soumis à trois types de tâches spatiales : la construction, le rappel spontané et le rappel indicé de la carte cognitive.
Puisque le cortex frontal est particulièrement vulnérable à une privation
de sommeil et que la privation de sommeil totale et sélective post-apprentissage cause des déficits dans certaines tâches, nous supposons 1) qu'une brève privation de SP pré-apprentissage induira des déficits au niveau de la tâche d'alternance différée chez le rat et 2) qu'une PST pré-apprentissage induira des déficits au niveau de la construction, du rappel spontané et du rappel indicé chez l'humain. De plus, nous prévoyons que la méthode de la petite plate-forme sera efficace dans la réduction substantielle de SP. Nos résultats montrent que les rats privés de SP ont éprouvé davantage de difficultés dans l'encodage de la tâche de mémoire de travail que dans celle de mémoire de référence. Les enregistrements de sommeil révèlent une diminution significative et spécifique de SP par la méthode de la petite plate-forme. Chez l'humain, nos résultats démontrent que les sujets PST ont éprouvé plus de difficultés seulement dans la construction de la carte cognitive lors de l'apprentissage de l'itinéraire le plus complexe. Dans ces deux tâches (alternance différée chez le rat; tâche complexe chez l'humain), la mémoire de travail, qui dépend en partie du cortex frontal, aurait pu être surchargée. Ces résultats suggèrent donc une sensibilité particulière des fonctions du cortex
frontal lors d'une privation de sommeil.
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Études d'interventions pharmacologiques au niveau de la Na+/K+-ATPase et des récepteurs des minéralocorticoïdes durant la gestation avec ou sans supplément sodiqueProvencher, Mylène January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
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Ajustement biologique du mélèze aux variations environnementales le long d'un gradient altitudinal : approche microdensitométrique de la réponse au climatNardin, Maxime 29 November 2013 (has links) (PDF)
La forte variation climatique, notamment de la température qui est associée à la distribution altitudinale de certains peuplements d'arbres forestiers peut induire des pressions de sélection divergentes favorisant l'expression de phénotypes différents en fonction de l'altitude. Cette thèse a pour objectif de déterminer si des adaptations locales existent et peuvent être mises en évidence dans un peuplement de mélèze (Larix decidua Mill.) distribué le long d'un gradient altitudinal situé dans les Alpes françaises, à proximité de Briançon. Quatre placettes d'environ 200 mélèzes ont été délimitées à 2300 m, 2000 m, 1700 m et 1350 m d'altitude le long de ce gradient. Une variabilité phénotypique significative a été observée entre ces niveaux altitudinaux pour la plupart des caractères étudiés : circonférence, hauteur de l'arbre, pourcentage d'aubier ainsi que pour toutes les variables microdensitométriques de cernes sauf une (la largeur de cerne). Une analyse de génétique des populations utilisant des marqueurs microsatellites a mis en évidence une faible influence de la dérive génétique sur la diversité génétique et une forte intensité de flux de gènes entre les différents niveaux altitudinaux étudiés. La différenciation génétique inter-altitudes a été estimée à l'aide d'une approche in-situ basée sur les données phénotypiques seules (PST) et comparée à la différenciation observée à l'aide des marqueurs microsatellites (FST). Cette analyse indique que l'hypothèse d'adaptations locales avec l'altitude peut être raisonnablement avancée pour les caractères de hauteur, circonférence, pourcentage d'aubier et densité du bois initial. Au contraire, l'adaptation locale n'apparait pas comme une hypothèse acceptable pour les caractères de largeur de cerne, surface de cerne, largeur du bois final et densité du bois final.
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Etude des mécanismes favorisant la dispersion et la survie intracellulaire de Mycobacterium tuberculosis / Study of the mechanisms stimulating Mycobacterium tuberculosis propagation and intracellular survivalVanzembergh, Frédéric 17 July 2011 (has links)
A ce jour, l’Organisation Mondiale de la Santé estime qu’un tiers de la population mondiale est infectée par Mycobacterium tuberculosis (Mtb), l’agent étiologique de la tuberculose. De par un taux de mortalité et de morbidité élevé, cette maladie infectieuse constitue un véritable fléau sanitaire au niveau mondial. <p>Mtb est un pathogène intracellulaire qui infecte son hôte par voie aérienne. In vivo, il doit faire face à une série d’environnements (phagosome, granulome) stressants de par leurs activités antimicrobiennes et par leur composition en nutriments relativement pauvre. Pour pouvoir survivre et se multiplier dans ces conditions, Mtb possède un panel de transporteurs spécifiques ainsi que toute une série de mécanismes pour contrer, voire détourner les défenses immunitaires de l’hôte. Malgré cette oppostion, les mycobactéries finissent séquestrées à l’intérieur de granulomes, structure caractéristique de la tuberculose, dans un état de dormance. La mise au point de nouveaux traitements prophylactiques et thérapeutiques nécessite la compréhension des mécanismes mis en œuvre par Mtb pour survivre et se multiplier au sein de son hôte.<p><p>Le présent travail a consisté en l’étude de mécanismes favorisant la dispersion et la survie intracellulaire de Mtb chez son hôte via: <p>1)\ / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
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Analysis of Selection and Genetic Drift in a Dioecious Plant : Spatial Genetic Structure and Selection in Phenotypic Traits in a Young Island Population of Silene dioicaAndersson, Bea Angelica January 2014 (has links)
Selection and genetic drift are often competing forces in shaping genetic structure in populations. Genetic drift will often effectively cancel out the effect of selection when population sizes are small, such as in colonizing island populations. On a small island in the Skeppsvik Archipelago in northern Sweden, a newly founded population of Silene dioica has been monitored since it first established around 1993. Though inhabiting an area of merely 173 m2, the population has been shown to exhibit a genetically differentiated patch structure where closely related individuals are tightly grouped, distanced from other family groups. In this study, the effect of selection was evaluated as compared to that of genetic drift. Variation in phenotypic traits in flowers, leaves and stalks were compared to that of neutral markers, in the form of PST and FST measures, to assess a measure of what proportion of differentiation among patches in phenotypic traits could not be attributed to genetic drift. Males and females were analysed separately to obtain measures of sex specific selection. Signs of divergent and stabilizing selection were found in several traits in both males and females despite the small spatial scale and short time since colonization. Further analysis is needed to assess explanations for trait divergence among patches and direction of selection.
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Simulation and Testing of Energy Efficient Hydromechanical Drivlines for Construction EquipmentLarsson, Viktor, Larsson, L. Viktor January 2014 (has links)
Increased oil prices and environmental issues have increased a need of loweringthe emissions from and the fuel consumption in heavy construction machines. Anatural solution to these issues is a lowered input power through downsizing ofthe engine. This implies a demand on higher transmission efficiency, in order tominimize the intrusion on vehicle performance. More specifically, alternatives tothe conventional torque converter found in heavier applications today, must beinvestigated. One important part of this is the task of controlling the transmissionwithout jeopardising the advantages associated with the torque converter, such asrobustness and controllability.In this thesis, an alternative transmission concept for a backhoe loader is investigated.The studied concept is referred to as a 2-mode Jarchow power-splittransmission, where a mechanical path is added to a hydrostatic transmission inorder to increase transmission efficiency. The concept is evaluated in computerbased simulations as well as in hardware-in-the-loop simulations, where a physicalhydrostatic transmission is exposed for the loads caused by the vehicle duringvarying conditions. The loads are in turn simulated according to developed modelsof the mechanical parts of the vehicle drive line.In total, the investigated concept can be used instead of the torque converterconcept, if the hydrostatic transmission is properly controlled. The results alsoshow that there is a high possibility that the combustion engine in the backhoeloader can be downsized from 64 kW to 55 kW, which would further increase thefuel savings and reduce the emissions.
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