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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Kalibrace robotického pracoviště / Calibration of Robotic Workspace

Uhlíř, Jan January 2019 (has links)
This work is concerned by the issue of calibrating a robotic workplace, including the localization of a calibration object for the purpose of calibrating a 2D or 3D camera, a robotic arm and a scene of robotic workplace. At first, the problems related to the calibration of the aforementioned elements were studied. Further, an analysis of suitable methods for performing these calibrations was performed. The result of this work is application of ROS robotic system providing methods for three different types of calibration programs, whose functionality is experimentally verified at the end of this work.
122

Validité de construit d’une traduction française du Post-Traumatic Stress Disorder Cheklist For DSM-5 auprès d’une population clinique au prise avec un trouble de stress post-traumatique

Savard-Kelly, Patrick 08 1900 (has links)
Contexte théorique : Au Canada, la prévalence du trouble de stress post-traumatique (TSPT) serait de 9,2%. Plusieurs questionnaires ont été développés pour mesurer les symptômes du TSPT dont le PTSD Checklist For DSM-5 (PCL-5). Ce questionnaire autorapporté a été validé à plusieurs reprises avec des échantillons non-cliniques ou militaires. Toutefois, le PCL-5 n’a jamais été validé avec un échantillon clinique et civil. Aussi, le nombre idéal de facteur du PCL-5 reste toujours à être démontré. Objectif : Cette étude vise à établir la validité de construit du PCL-5 d’un échantillon clinique et civil de 132 participants aux prises avec un TSPT. Les 3 principales structures factorielles seront analysées de façon à retenir celle qui présente les meilleurs résultats. Méthodologie : Les structures factorielles ont été mesurées avec des analyses factorielles confirmatoires et des analyses bifactorielles. La consistance interne a été mesurée à partir du coefficient Oméga de McDonald. La validité convergente et divergente a été mesurée par des corrélations de Pearson avec d’autres construits. Résultats : Au niveau des indices d’ajustement, le modèle à 7 facteurs a obtenu les meilleurs résultats. Sur le plan de la fidélité et sur celui de la validité convergente et divergente, le modèle à 4 facteurs possède les résultats les plus optimaux. Discussion : Globalement, le modèle à 4 facteurs est le plus approprié pour le PCL-5. De plus, les modèles à 6 et 7 facteurs présentent quelques lacunes sur le plan méthodologique et statistique. Finalement, le PCL-5 est un questionnaire valide et fidèle pour une population clinique et civile. / Background: In Canada, the prevalence of post-traumatic stress disorder (PTSD) is estimated to be 9.2%. Several questionnaires have been developed to measure the symptoms of PTSD including the PTSD Checklist For DSM-5 (PCL-5). This questionnaire has been validated several times with non-clinical or military samples. However, PCL-5 has never been validated with a clinical and civilian sample. Also, the ideal factor number of PCL-5 has yet to be demonstrated. Objective: This study aims to establish the construct validity of PCL-5 in a clinical and civilian sample of 132 participants with PTSD. The 3 main factor structures will be analyzed in order to retain the one that presents the best results. Methodology: Factor structures were measured with confirmatory factor analyzes and bifactor analyzes. Internal consistency was measured from McDonald's Omega coefficient. Convergent and discriminant validity was measured by Pearson correlations with other constructs. Results: In terms of fit statistics, the 7-factor model obtained the best results. In terms of reliability and convergent and divergent validity, the 4-factor model has the most optimal results. Discussion: Overall, the 4-factor model is the most appropriate for the PCL-5. In addition, the 6 and 7 factor models have some methodological and statistical limitations. Finally, the PCL-5 is a valid and reliable questionnaire for a clinical and civilian population.
123

Příčiny předčasné ztráty kapacity olověných akumulátorů pracujících v PSoC režimu hybridních elektrických vozidel / Causes of Premature Capacity Loss of Lead-Acid Accumulators Operating in PSoC Mode in Hybrid Electric Vehicles

Bilko, Radek January 2014 (has links)
This thesis is completion of whole stage of researches and it is a result of existing need of increase efficiency, utilization rate and service life of lead acid batteries VRLA planned for utilization in hybrid electric vehicles in mode of partial state-of-charge PSoC. During the application of mode PSoC at lead acid battery occurs irreversible sulfation of negative electrodes and thus to loss their charging capability. This phenomenon, according to the latest trend called PCL3, isn´t connected with subsequently referred effects PCL1, PCL2, show up on positive electrodes. Result of this thesis is finding a new types of additives, determine their optimum amount and size in such a way that innovated composition of negative active materials be able to resist sulfation of negative electrode during operation in mode PSoC. Part of the effort to clarify actions ongoing on negative active material and causes non-returnable sulfation electrodes is also monitoring of structural changes electrode active material by using environmental scanning electron microscope, which helped to clarify processes related with loss of capacity in mode PSoC. Special attention during reserches was focused on study of the properties contact layers between collector and electrodes active material and itself active materials lead-acid battery druring exploitation. There were gain new information about influence repeated cycling of (charging, discharging) the critical area of the electrodes. Measurements was carried out on specially prepared experimental electrodes DC Difference Method, this enabled obtain data in situ.
124

INTERAKCE V ROZTOCÍCH A GELECH NA PODNĚTY REAGUJÍCICH POLYMERNÍCH SYSTÉMŮ STUDOVANÝCH NMR SPEKTROSKOPIÍ / Interactions in solutions and gels of stimuli-responsive polymer systems investigated by NMR spectroscopy

Konefał, Rafał January 2018 (has links)
Stimuli-responsive (stimuli-sensitive, intelligent, or smart) polymers are polymer materials which, after small external stimuli, evidently change their physical or chemical properties. Smart polymers can be classified according stimuli they respond to such as: temperature changes, mechanical stress, light irradiation, ultrasonic treatment, application of external magnetic as well as electric field, changes of pH, ionic strength, addition of the chemical agents and presence of biomolecules and bioactive molecules. Stimuli-responsive synthetic polymer systems has attracted considerable attention due to wide range of applications, i.e. controlled drug delivery and release systems, diagnostics, tissue engineering and 'smart' optical systems, as well as biosensors, microelectromechanical systems, coatings, and textiles. Among the types of stimuli for this dissertation temperature, pH and reactive oxygen species (ROS) responsive polymer systems were studied. In case of thermoresponsive polymers, when polymer chains are molecularly dissolved in a good solvent, changes (increasing or decreasing) of temperature result in insolubility (globular nanoparticles formation) of polymer chains, called temperature induced phase-separation. pH responsive polymers change properties such as: solubility, volume (gels),...
125

Stabilita systémů pro řízené uvolňování léčiv na bázi plastifikovaného škrobu / Stability of controlled drug release systems based on plasticized starch

Zhukouskaya, Hanna January 2022 (has links)
The thesis is focused on the research of stability of controlled drug release systems based on a blend of plasticized starch/polycaprolactone (TPS/PCL) that served as a carrier. Antibiotic vancomycin was used as a model drug, and its release from TPS/PCL pellets into aqueous environment was followed by UV-spectroscopy and the obtained time dependences were treated by a simple kinetic model. Moreover, the simultaneous release of starch particles to the surrounding liquid phase was studied by static and dynamic light scattering as well as transmission electron microscopy (TEM) in order to obtain information on the stability of biodegradable matrix and on the structure of the products of the pellet decomposition on a nanoscale level. Key words: vancomycin, starch, drug delivery system, polycaprolactone (PCL), particle release, dynamic light scattering (DLS), static light scattering (SLS)
126

Preparation and in vivo efficient anti-infection property of GTR/GBR implant made by metronidazole loaded electrospun polycaprolactone nanofiber membrane

Xue, J., He, M., Niu, Y., Liu, H., Crawford, A., Coates, Philip D., Chen, D., Shi, R., Zhang, L. January 2014 (has links)
No / Infection is the major reason of GTR/GBR membrane failure in clinical application. In this work, we developed GTR/GBR nanofiber membranes with localized drug delivery function to prevent infection. Metronidazole (MNA), an antibiotic, was successfully incorporated into electrospun polycaprolactone (PCL) nanofibers at different concentrations (0, 1, 5, 10, 20, 30, and 40 wt% polymer). To obtain the optimum anti-infection membrane, we systematically investigated the physical-chemical and mechanical properties of the nanofiber membranes with different drug contents. The interaction between PCL and MNA was identified by molecular dynamics simulation. MNA released in a controlled, sustained manner over 2 weeks and the antibacterial activity of the released MNA remained. The incorporation of MNA improved the hydrophilicity and in vitro biodegradation rate of PCL nanofibers. The nanofiber membranes allowed cells to adhere to and proliferate on them and showed excellent barrier function. The membrane loaded with 30% MNA had the best comprehensive properties. Analysis of subcutaneous implants demonstrated that MNA-loaded nanofibers evoked a less severe inflammatory response than pure PCL nanofibers. These results demonstrate the potential of MNA-loaded nanofiber membranes as GTR/GBR membrane with antibacterial and anti-inflammatory function for extensive biomedical applications.
127

Fabrication, Characterisation and Optimisation of Biodegradable Scaffolds for Vascular Tissue Engineering Application of PCL and PLGA Electrospun Polymers for Vascular Tissue Engineering

Bazgir, Morteza January 2021 (has links)
Annually, about 80,000 people die in the United Kingdom due to myocardial infarction, congestive heart failure, stroke, or from other diseases related to blood vessels. The current gold standard treatment for replacing the damaged blood vessel is by autograft procedure, during which the internal mammary artery (IMA) graft or saphenous vein graft (SVG) are usually employed. However, some limitations are associated with this type of treatment, such as lack of donor site and post-surgery problems that could negatively affect the patient’s health. Therefore, this present work aims to fabricate a synthetic blood vessel that mimics the natural arteries and to be used as an alternative method for blood vessel replacement. Polymeric materials intended to be used for this purpose must possess several characteristics including: (1) Polymers must be biocompatible; (2) Biodegradable with adequate degradation rate; (3) Must maintain its structural integrity throughout intended use; (4) Must have ideal mechanical properties; and (5) Must encourage and enhance the proliferation of the cells. The feasibility of using synthetic biodegradable polymers such as poly (ε- caprolactone) (PCL) and poly (lactide-co-glycolic acid) (PLGA) for fabricating tubular vascular grafts was extensively investigated in this work. Many fundamental experiments were performed to develop porous tissue- engineered polymeric membranes for vascular graft purposes through electrospinning technique to achieve the main aim. Electrospinning was selected since the scaffolds produced by this method usually resemble structural morphology similar to the extracellular matrix (ECM). Hence, four 6mm in diameter tubular shape vascular grafts PCL only, PLGA only, coaxial (core-PCL and shell-PLGA), and bilayer (inner layer-PCL and outer layer-PLGA) was designed and fabricated successfully. The structure and properties of each scaffold membrane were observed by scanning electron microscopy (SEM), and these scaffolds were fully characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), water contact angle measurements, mechanical tensile test, as well as cell culture studies were carried out by seeding human umbilical vein cells (HUVEC) and human vascular Fibroblast cells (HVF). Moreover, all polymeric grafts underwent degradation process, and the change in their morphological structure properties was studied over 12 weeks at room temperature. All scaffolds were also exposed to a controlled temperature of 37°C for four weeks, in phosphate-buffered saline solution (pH, 7.3). It was found that all scaffolds displayed exceptional fibre structure and excellent degradability with adequate steady weight-loss confirming the suitability of the fabricated scaffolds for tissue engineering applications. The coaxial and bilayer scaffolds degraded at a much slower (and steadier) rate than the singular PCL and PLGA tubular scaffolds. Coaxial grafts fabricated via coaxial needle showed an increase in their fibre diameter and pore size volume than other membranes, but also showed to have significant tensile strength, elongation at fracture, and Young’s modulus. To conclude, all scaffolds have demonstrated to be reliable to adhere and proliferate HUVEC, and HVF cells, but these cells were attracted to the PLGA membrane more than other fabricated membranes.
128

An Approach to Lens Regeneration in Mice Following Lentectomy and the Implantation of a Biodegradable Hydrogel Encapsulating Iris Pigmented Tissue in Combination with Basic Fibroblast Growth Factor

Baddour, Joelle 11 May 2012 (has links)
No description available.
129

Synthesis and Surface Modification of Nanoporous Poly(ε-caprolactone) Membrane for Biomedical Applications

Yen, Chi January 2010 (has links)
No description available.
130

Unmasking the unwanted: Which dimension of psychopathy predicts antisocial behavior?

Unge, Victoria January 2023 (has links)
This study examined the predictive value of the three dimensions of youth psychopathic personality towards delinquency, on delinquency through the application of hierarchical regression analysis, while controlling for gender. Dimensions being: Callous/Unemotional-, Impulsive/Irresponsible-, and Grandiose/Manipulative traits. The study included 891 (48% female) Swedish adolescents from a community sample with a mean age of 14.28 (SD=.94) years. A self-report instrument was used to assess psychopathic traits in youth, the Youth Psychopathic Traits Inventory (YPI), consisting of 50 items and is specifically designed to lower the risk of response bias. Results: It was discovered that Impulsivity/Irresponsible behavior predicted statistically significant 14% of the variance in delinquency, and gender significantly predicted 4%. Callous/Unemotional predicted non-significant 0,3% and Grandiose/Manipulative predicted none of the variance in delinquency and was not significant. The findings regarding dimensions contradict the majority of research on the subject which has focused on CU-traits as main predictor of antisocial behavior, but in line with recent studies using a similar analytical approach showing Impulsivity/Irresponsible behavior as main predictor. The findings regarding gender are in line with previous research.

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