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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

Variace abnormalit foramen obturatum a retropubického prostoru a jejich vztah ke komplikacím páskových operací / Variation of abnormalities of foramen obturatum and retropubic space and its relation to complications of tape surgery

Hubka, Petr January 2011 (has links)
Introduction: The knowledge of anatomy is crucial for introduction of new surgical methods. It is also of especial use while dealing with surgical complications during surgeries with limited surgical field, where the way of approach limits the management of complications. It was assumed that common anatomical variations would influence different efficacy of surgeries and would explain potential complications. Methods: During anatomical dissections fifty female cadavers were dissected and tension-free vaginal tapes TVT-S H, TVT-S U, TVT Abbrevo and Ajust were studied. A novel descriptive system for localisation of the tape was created. During the dissection the tape was located and its localisation and fixation was described. Results: Common anatomical variation in the sample was corona mortis with frequency of 72 %. Preperitoneal fatty plug, which is recognized by some authors as the first stage of obturator hernia, was found in 40 % in obturator canal. The proper fixation of TVT-S H was achieved in 53.6 %. In 10.5 % urinary bladder was injured. In case of TVT-S U the proper fixation occurred in 63.8 %. In two cases the inserter was nearby corona mortis. Within the group of TVTO Abbrevo the tape was fixated properly into the obturator complex (consists of the obturator membrane and obturator muscles) in...
122

Hemorrhagic Complication During Placement of Tension-Free Vaginal Tape

Huffaker, R. K., Handcock, Tyler, Muir, Tristi W. 01 January 2010 (has links)
A 66-year-old para III with a 20-year history of stress urinary incontinence underwent placement of tension-free vaginal tape. Intraoperative arterial bleeding occurred. An expanding hematoma was palpated postoperatively. Interventional radiology performed a pelvic arteriogram with selective bilateral internal iliac arteriograms, a supraselective anterior division and obturator arteriogram, a left external iliac arteriogram, coil embolization of a branch of the left obturator artery, and gel foam embolization of the anterior division of the left internal iliac artery.
123

The Effects of Kinesiology Tape on Static Postural Control in Individuals with Functional Ankle Instability

Ly, Kien Trung 03 September 2020 (has links)
Functional ankle instability (FAI) is characterized by the recurrent giving way of the ankle and the constant feeling of instability that affects the quality of life of its patients adversely. Kinesiology Tape (KT), differed from the traditional rigid athletic tape, becomes more popular as a new therapeutic tool for injuries management. It is reported to decrease pain, promote blood circulation and natural healing of muscular functioning. However, scientific evidence of KT’s effects on FAI remains very limited. Therefore, the purpose of the present study was to investigate if applying KT on the unstable ankle may improve static postural control in individuals with FAI. Twenty young adults with FAI performed a series of static quiet bipedal and unipedal stances on a force platform. Postural control was assessed by four measures derived from the centre of pressure (COP) data: 95% Confidence ellipse of total displacements (area), standard deviation of displacements (SD), mean velocity and mean power frequency (MPF). Measurements were taken at three different times: baseline or no tape, immediately after the application of KT on the unstable ankle, and 24 hours after the taping application with the tape remaining on the ankle. Results revealed only minor changes in mean velocity and MPF in unipedal stances immediately after KT application. However, the overall results indicated statistically insignificant improvements in postural control performance neither immediately after KT application nor after 24 hours. In conclusion, our results suggest that the use of KT did not affect bipedal and unipedal stances of individuals with functional ankle instability.
124

Krapp's Last Tape Under Quarantine: A Contemporary Adaptation

Eggenschwiller, Seth 10 May 2021 (has links)
No description available.
125

Concrete Fading and its Effect on Students’ Algebraic Problem Solving and Computational Skills

Chen, Lisa Allison January 2022 (has links)
Algebra I encompasses several topics that serve as a basis for students’ subsequent mathematics courses as they progress in school. Some of the key topics that students struggle with is solving linear equations and algebraic word problems. There are several factors that may contribute to this ongoing struggle for students such as the structure of the textbooks, the teacher instruction and misconceptions of components of algebraic equations. A promising solution to the potential contributing factors is concrete fading. In this study, concreteness fading refers to an instructional technique that represents topics in a particular sequence from a concrete, real-world representation to a semi-concrete diagram (e.g., tape diagram) to an abstract representation (e.g., algebraic equations). The current study aims to investigate the influence concrete fading has on student learning while studying concrete fading in two ninth grade Algebra I general education classes at an urban high school. In particular, the study aims to answer the following: 1) What are some ways that students who received concrete fading think differently than the control group? 2) How do these differences seem to be related to the intervention? Both classes were taught by the same teacher. One class was assigned to the treatment group that received the concrete fading lessons and the other class was assigned to the control group that was taught as business as usual by the teacher. The study was intended to be quasi-experimental study, but due to challenges, it was primarily qualitative in nature focusing on eight students where the analysis included analyzing student work and student interviews responses along with quantitative analysis of the pre and two post-tests. Results revealed that the treatment group does think differently than the control group based on student work and the interview responses. / Math & Science Education
126

Analyzing the Effectiveness of Kinesio-taping in Golf-induced Chronic Low Back Pain Management

Zhang, Yushan 01 January 2023 (has links) (PDF)
The purpose of this study was to investigate the effectiveness of Kinesio-Taping (KT) in golf-induced chronic low-back pain management. The golfing population continues to grow each year, and the risks of golf-induced chronic low back pain (CLBP) remain high. The Kinesio-taping technique is a non-invasive treatment intervention utilized in sports injury rehabilitation and prevention. Due to the lack of research on KT in golf-related injuries, this study addresses the injury mechanism of golf-induced CLBP and the proposed physiological mechanism and therapeutic effects on the musculoskeletal system of KT. This study is a comprehensive review of the golf swing, prevalence and risk factors of golf induced CLBP, treatment modalities for non-specific low back pain, and the use of KT in sports medicine and healthcare settings. The target population of this study includes active adults and older adults who are at risk or currently experiencing CLBP and those who may golf professionally or recreationally. The literature search (February- October 2022) was performed using multiple databases, including UCF Libraries, PubMed, GoogleScholar, SagePub, ScienceDirect, and Ebscohost. Keywords employed by this research include "low back*" "golf*" or "golf swing*" "Kinesio-tape*" or "Kinesio-taping*" and "pain*" or "injury*". Search results were carefully screened, and relevant literature was selected for this study. A total of 78 scientific studies were included in this review. This literature review found insufficient empirical evidence to support the application of KT in golf-induced low back pain management. Although the subjects' contextual effects should not be overlooked, the reasoning behind how KT physiologically affects target injury sites remains unclear. Further research is suggested to examine the effectiveness of KT in treating golf induced CLBP.
127

Understanding How Tape Casting Titanium Diboride Shifts its Processing-Microstructure-Properties Paradigm Toward New Applications

Shirey, Kaitlyn Ann 07 September 2023 (has links)
The manufacturing of UHTC materials has significantly advanced over recent years, allowing for the development of new microstructures, architectures, shapes, and geometries to explore new properties and applications for these materials beyond aerospace. One of the UHTCs, titanium diboride (TiB2) exhibits high electrical and thermal conductivity that could satisfy the needs of functional ceramic component applications, like battery cathodes, by tailoring its microstructure and architecture. This thesis represents one of the first detailed studies to understand how the processing-microstructure-properties relationship of TiB2 can be shifted to explore new applications. In order to do that, TiB2 has been manufactured with a processing technique never used before, with significant porosity, exploration of which has been very limited for this material. Additionally, this thesis also explores the synthesis and utilization of novel anisotropic particles to further explore this material relationship. In this work, aqueous tape casting of TiB2 has been investigated. Zeta potential measurements and suspension rheology were used to understand the role of dispersant, binder and plasticizer in the suspension and their interaction with the surface chemistry of the TiB2 particles to develop a stable, homogenous suspension, with minimum additive amounts (0-2 wt%). Homogeneous, flexible and strong TiB2 tapes were prepared using suspensions with 30 vol% solids and characterized to compare different compositions, mixing methods, and thicknesses. The characterization shows the tailoring of the properties as a function of the controlled suspension formulation with minimum amount of additives. Green tapes with 2 wt% dispersant, 1 wt% binder, and 2 wt% plasticizer had similar microstructure to those with half the plasticizer but quintuple the Young's modulus (1.96 GPa). The effect on other relevant properties is also discussed. Tape casting aligns anisotropic particles along the direction of casting, which can be taken advantage of for increasing fracture toughness directionally or producing aligned pore networks using sacrificial fillers. The relationship between alignment, porosity, and the mechanical properties of titanium diboride has not been studied. In this work, we characterize the porous sintered bodies produced through aqueous tape casting of non-spherical TiB2 particles of aspect ratio close to 1, as well as composites with an added high aspect ratio particle (2 wt% PCN-222). Synthesis of uniform, spherical ZrC is difficult and generally not cost-effective, as is the case for most ultra-high temperature ceramics. High aspect ratio particles for reinforcement of ceramic composites are even more difficult to synthesize. Metal organic frameworks (MOF) are crystalline coordination polymers composed of multidentate organic linkers bridging metal nodes to form porous structures. Thermal decomposition of MOFs presents a new and cost-effective route to synthesis of ZrC. In this study, heat treatment at 2000°C of MOF PCN-222 produces zirconium carbide (ZrC) within a highly anisotropic particle. The resulting rod-shaped, glass-like carbon matrix embedded with ZrC crystals is described. These rods have potential as reinforcements for iii high temperature applications and as a synthetic route for ultra-high temperature ceramics with unique morphologies. It is the first time that this type of transformation from a MOF into a UHTC has been reported. We have determined through analysis of SEM images that regardless of tape casting speed, about 57% of the TiB2 particles are aligned with the tape casting direction. The mechanical properties are dominated by the effects of the porosity (38%), but the alignment exhibited here could be further exploited for anisotropic behavior across the sintered tapes. Composites cast with high aspect ratio particles exhibited strong alignment in the casting direction. Further work is required to understand the interplay between alignment and porosity and their effects on material properties. / Doctor of Philosophy / Titanium diboride (TiB2) is an ultra-high temperature ceramic with a melting point of 3225°C. Many applications for this material require fully dense structural ceramics, such as cutting tools,1 armor,2 and high temperature structural supports.2,3 These applications rely mainly on the high mechanical strength of TiB2, which is maintained in extreme thermal and chemical environments. The field of knowledge surrounding TiB2 lacks information about the ways that porosity affects its otherwise well-known properties;4,5 to bridge this gap could open up applications for functional and porous ceramics such as lithium-air batteries,6 electrochemical components,7 semiconductors,8 and more. This work intends to provide a foundation for this endeavor by developing for the first time a colloidal suspension formulation that allows for the tape casting of TiB2 and characterizing the resulting porous ceramics. Among these new potential applications, many require thin ceramics less than 1 mm thick—a result which has been accomplished for other materials via tape casting.4,9 This is a wet route of producing ceramics that provides the ability to tailor the surface chemistry of the particles, giving greater control over the stability of the suspension (TiB2 particles suspended in water) and quality of the end product than is afforded by dry processing routes.10 This also allows for more complex shaping than simple pressing, which ultimately saves costs; by producing the near-net shape in the green body before firing, less machining must be done to the sintered body when it is removed from the high temperature furnace.11 In tape casting, the suspension is spread over a substrate by a doctor blade to the desired thickness. It is known that tape casting tends to align anisotropic particles along the direction of casting due to a nonuniform velocity imparted by the shear force of the doctor blade spreading the suspension, an advantage which can provide directional properties in the final ceramic.9 While this process is well known, it has never been applied to the material TiB2 prior to this work. In this work, a suspension is formulated to allow for the tape casting of TiB2 with minimum organic additive content, which is cost-effective and reduces potential for defects. Porosity and alignment in the tape cast specimens are characterized. For comparison, a highly anisotropic or rod-shaped particle (PCN-222, a metal organic framework material) was included in the TiB2 suspensions for tape casting. This metal organic framework (MOF) has been transformed into a high temperature material after thermal treatment at the sintering temperature of 2000°C, showing that the resulting particle is made of glass-like carbon embedded with zirconium carbide (ZrC) crystallites. This particle could be used as a reinforcement for ultra-high temperature ceramics, and in this work was shown to align strongly in the tape casting direction. At the level of porosity (38%) and alignment (57%) in the TiB2 specimens in this study, porosity dominates the mechanical properties. This relationship is shown to be more complicated than lowering the strength by the same proportion that the density is lowered, and various models for understanding the role of porosity on the elastic modulus are explored.
128

Innovative unidirectional recycled carbon fiber tape structure for high performance thermoplastic composites: technological developments, technology-structure-property relationship and modeling of composite tensile properties

Khurshid, Muhammad Furqan 28 February 2023 (has links)
The rapidly growing demand for carbon fiber reinforced plastics in high-tech industries, such as aerospace, defense, automotive, wind turbine engineering, building and sports, resulted in a high amount of waste in the form of dry waste (e.g., production off-cuts), wet waste (e.g., out-of-date prepreg) and end-of-life components waste (e.g., aircraft components). Furthermore, the production of carbon fibers is cost and energy-intensive. Therefore, technological developments for the gentle processing of recycled carbon fiber and its integration into high-performance composites with promising tensile properties have gained considerable attention. Consequently, injection molding, nonwovens and hybrid yarn technologies were developed in recent years to integrate recycled carbon fiber into the high-performance thermoplastic composite. It is unfortunate that these technologies develop composites with a lack of unidirectional fiber orientation; therefore, the potential of recycled carbon fiber in high-performance composites is not thoroughly exhausted. This thesis primarily addresses the development of an innovative structure with a unidirectional fiber orientation termed “unidirectional recycled carbon fiber tape structure” for high-performance thermoplastics composites. The technological concept of the unidirectional structure comprises fiber opening, carding, drawing and a novel tape-forming process. In this concept, fiber opening, carding, and drawing processes were utilized to develop homogeneous, uniform, and highly oriented hybrid slivers. In the next step, these hybrid slivers were converted into a unidirectional recycled carbon fiber tape structure through a novel tape-forming process. To implement this concept, technological developments (investigations, modifications, optimization and further developments), were carried out in fiber opening, carding and drawing processes to develop a hybrid sliver with improved uniformity, homogeneity and unidirectional orientation. In the second phase, conception, design, technological developments, construction and prototype development were implemented to develop a novel tape-forming process. The result confirms that tape development technology comprising fiber opening, carding, drawing and prototype tape forming processes is an innovative, eco-friendly and sustainable technology compared to existing technologies. Furthermore, the consolidation process transformed the unidirectional tape structure into high-performance thermoplastic composites. Subsequently, technology-structure-property relationships were established to develop composites with tailor-made properties. The analysis reveals that selecting optimum technological, consolidation and structural parameters develop tape and composite structures with unidirectional fiber orientation. As a result, experimental results of a high-performance composite developed from a unidirectional recycled carbon fiber tape structure show a very high tensile strength of 1350 ± 28 MPa and an E-module of 84.7 ± 2.3 GPa. This analysis confirms that unidirectional fibers configuration in composites brings a revolution toward developing cost-efficient, high-performance composites for load-bearing structural applications. Finally, theoretical and finite element modeling of tensile properties of high-performance composites reveals that modified models show good agreement with composite tensile properties.
129

Processing of Cubic Stabilized Zirconia Electrolyte Membranes For Electrolyte-Supported Single Cell Solid Oxide Fuel Cells Using Tape Casting

Coronado Rodriguez, Arturo 01 January 2018 (has links)
Electrochemical conversion devices are a developing technology that prove to be a viable and more efficient alternative to current environmentally friendly generation devices. As such, constant research has been done in the last few decades to increase their applications and reliability. One of these systems, and the focus of this research, is the single cell Solid Oxide Fuel Cell (SOFC). These systems are a developing technology which main caveat is the need of high operating temperatures and costs. As such, most multidisciplinary research has been focused on researching materials and/or processes that help mitigate the costs or lower the operating temperature. The research presented in this paper focused on the manufacturing of a cubic stabilized zirconia (CSZ) electrolyte thin membrane for a single cell SOFC through tape casting. Thus, the process was divided into slurry preparation, tape casting, further processing, and analysis of samples. First the tape was produced reaching optimal viscosity (between 500 to 6000 cP) and minimizing impurities. Then, the slurry was poured into the doctor's blade with a 200 micrometers gap and allowed to dry. Samples were punched from the green tape with a diameter of 28 inches. Afterwards, these samples were pressed and sintered with a force of 218016 N and temperature of 1550 degrees celsius, respectively. These steps are done to maximize density and grain growth and minimize porosity. Lastly, the tape went further analysis and it was stated that further research should be done to determine this tape viability for stationary SOFC application.
130

Work for Five-String Electronic Violin and Tape (Torn Edges)

Borden, Stacy R. 29 July 2008 (has links)
No description available.

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