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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

Control strategies for blended braking in road vehicles : a study of control strategies for blended friction and regenerative braking in road vehicles based on maximising energy recovery while always meeting the driver demand

Zaini January 2012 (has links)
In HEV and EV, higher fuel economy is achieved by operating the ICE and electric motor in the most efficient region and by using regenerative braking. Such a braking system converts, transfers, stores and reuses kinetic energy which would otherwise be dissipated as heat through friction brakes to the environment. This research investigates the control of braking for a mixed-mode braking system in a these vehicles based on the proportion of braking energy that can be stored. Achieving mixed-mode braking requires the ‘blending’ of the two systems (regenerative and friction), and in brake blending, the electric motor/generator (M/G) and the hydraulic actuation pressure are controlled together to meet the driver’s braking demand. The research presented here has established a new robust dynamic modelling procedure for the design of combined regenerative and hydraulic braking systems. Direct torque control and pressure control were selected as the control criteria in both brakes. Two simulation models have been developed in Matlab/Simulink to generate analysis the performance of the control strategy in the blended braking system. Integration of the regenerative braking system with ABS has also been completed, based on two conditions, with and without the deactivation of the regenerative braking. Verification of the models is presented, based on experimental work on two EVs manufactured by TATA Motors; the ACE light commercial vehicle and the VISTA small passenger car. It is concluded that braking demand and vehicle speed determine the operating point of the motor/generator and hence the regenerative braking ratio.
122

The fruits of landscape: the power of landscape in presenting sustainable food production

Mann, William T. January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional & Community Planning / Laurence A. Clement, Jr. / Our current agricultural system in the U.S. involves procedures that appear to maintain high levels of productivity. However, the long-term outlook regarding this system indicates an overall degradation of the ecological resources that generate the abundance of agricultural products to which we are accustomed (Lyle, 1994). This project applies sustainable food production strategies specifically addressed in permaculture as a regenerative alternative to industrial agriculture to a site on the Kansas State University campus. This research initiative quantifies the productive benefits of sustainable agriculture in providing for the Derby Dining Hall, and illustrates how sustainable food production strategies can be shaped through landscape form and space in ways that connect people with ecologically sound food production. The literature review addressed landscape architecture theory and sustainable agriculture. In addition, a set of interviews as well as three precedent studies helped to focus project considerations and to inform design decision-making. The site design process comprised the primary method for exploration and subsequent development of conclusions. The first two design iterations were performed with a specific focus on garden productivity and then garden form, with the third acting as a synthesis of the first two. The final plan suggests that there is a potential for a positive didactic experience of sustainable food production through the artful synthesis of landscape form, particularly with regard to carefully arranged circulation patterns. In addition it was found that, given the average growing season rainfall of 3 inches per month, the water harvested from the roofs of Moore and West residence halls can support over 7,300 square feet of intensive produce beds with a 1 inch per week application rate. In regard to food production, select non-bulk items on Derby Dining Hall’s menu (e.g. Parsley, Garlic, Basil, Kale, Radishes, Turnips, & Oregano) can be provided for or supplemented entirely, given the designed array of produce in the proposed gardens. It would appear that incorporating permaculture and organic farming strategies into the campus fabric would facilitate K-State Housing and Dining’s efforts to promote healthy food -- and sustainable thinking -- by increasing the variety, freshness and interest of its menu.
123

Lightweight friction brakes for a road vehicle with regenerative braking : design analysis and experimental investigation of the potential for mass reduction of friction brakes on a passenger car with regenerative braking

Sarip, S. Bin January 2011 (has links)
One of the benefits of electric vehicles (EVs) and hybrid vehicles (HVs) is their potential to recuperate braking energy. Regenerative braking (RB) will minimize duty levels on the brakes, giving advantages including extended brake rotor and friction material life and, more significantly, reduced brake mass and minimised brake pad wear. In this thesis, a mathematical analysis (MATLAB) has been used to analyse the accessibility of regenerative braking energy during a single-stop braking event. The results have indicated that a friction brake could be downsized while maintaining the same functional requirements of the vehicle braking in the standard brakes, including thermomechanical performance (heat transfer coefficient estimation, temperature distribution, cooling and stress deformation). This would allow lighter brakes to be designed and fitted with confidence in a normal passenger car alongside a hybrid electric drive. An approach has been established and a lightweight brake disc design analysed FEA and experimentally verified is presented in this research. Thermal performance was a key factor which was studied using the 3D model in FEA simulations. Ultimately, a design approach for lightweight brake discs suitable for use in any car-sized hybrid vehicle has been developed and tested. The results from experiments on a prototype lightweight brake disc were shown to illustrate the effects of RBS/friction combination in terms of weight reduction. The design requirement, including reducing the thickness, would affect the temperature distribution and increase stress at the critical area. Based on the relationship obtained between rotor weight, thickness and each performance requirement, criteria have been established for designing lightweight brake discs in a vehicle with regenerative braking.
124

Heating and Regenerative Cooling Model for a Rotating Detonation Engine Designed for Upper Stage Performance

Timothy P Gurshin (6866786) 02 August 2019 (has links)
<div>Rotating detonation engines (RDE) have the potential to significantly advance the efficiency of chemical propulsion. They are approximately one order of magnitude shorter than constant pressure engines, a savings benefit that is especially important for upper stage engines. There are many challenges to advancing their technological readiness level, but one area this thesis attempts to help mitigate is the understanding of heat loads and the viability of regenerative jacket cooling.<br></div><div> A one-dimensional, steady-state heat transfer and regenerative cooling model for the upper stage RL10A-3-3A (RL10) engine is developed in MATLAB. This model considers forced convection in the boundary layer between the combustion product gases and the hot-gas-side wall, conduction through the wall, and forced convection in the boundary layer between the hydrogen coolant and coolant-side wall. Variable gas and coolant transport properties are utilized to increase physical accuracy. The model also quantifies pressure drop through the cooling channels due to wall friction. This allows for overall heat flux, and consequently hot-gas-side and coolant-side wall temperatures to be predicted along the length of the engine. Properties of the coolant can also be predicted including the jacket outlet temperature and pressure. These cooling circuit final parameters, temperature rise and pressure drop, were matched to a more detailed, three-dimensional, transient RL10 system model developed by NASA, thereby anchoring this model.</div><div> An RDE is designed to notionally meet the thrust level of RL10. Model design decisions are documented and explained, and a detailed comparison of the two engine geometries is made. The regenerative cooling model is adapted for the RDE considering such unique aspects as detonative heat flux and the centerbody/plug nozzle. Steady state heating and cooling analysis is performed on the RDE and the results are compared to RL10. Investigation into the effects of the RDE’s differing cooling jacket output conditions on the turbine are calculated and discussed.</div><div> Appendix analyses consider more realistic detonative heat flux approximations according to recent RDE calorimetry studies and the effect of altering detonation chamber heat flux.</div><div> Even with the conservative assumption of throat-level heat flux everywhere in the RDE’s annular combustion chamber, regenerative jacket cooling shows promise as a means of thermal survival. Wall temperatures are reasonable, coolant temperature rise is lower, and coolant pressure drop is lower. The reduced temperature rise presents the new challenge of correctly powering the turbine since the incoming coolant is less energized. Further studies should also look at channel optimization specific to the RDE to maximize cooling performance and ease of system integration.<br></div>
125

Sinovite em equinos efeito das células tronco mesenquimais sobre a inflamação articular /

Rosa, Gustavo dos Santos. January 2019 (has links)
Orientador: Ana Liz Garcia Alves / Resumo: A alta exigência do sistema locomotor de equinos atletas resulta em pequenas lesões articulares que, cumulativamente, provocam inflamação sinovial e liberação de diversos mediadores inflamatórios no microambiente articular, resultando no desenvolvimento da osteoartrite (OA). A utilização de células tronco mesenquimais (CTMs) nestes casos visa modificar a progressão desta enfermidade. O objetivo do presente trabalho foi verificar o comportamento das CTMs alogênicas derivadas da membrana sinovial (CTMms) frente aos eventos inflamatórios em casos de sinovite aguda em equinos. A sinovite foi induzida utilizando 0,5ng de LPS via intra-articular (IA) e os animais foram tratados 8 horas após a indução. O grupo controle recebeu como tratamento 2 ml de PBS IA, enquanto o grupo tratado recebeu 107 CTMms IA. Foram realizados, de maneira seriada, exames físicos, exames do aparelho locomotor, análise citológica do líquido sinovial e a determinação da concentração sinovial de TGF-β e PGE2. Não foram observadas diferenças entre os grupos quanto à claudicação e parâmetros do exame físico. A análise citológica revelou diminuição significativa de linfócitos e macrófagos no grupo tratado (P= 0,0059 e P= 0,0003, respectivamente) que também apresentou menores níveis de TGF-β (P= 0,0467) no momento 24h. Os demais parâmetros não apresentaram diferença significativa em nenhum momento. Os dados avaliados sugerem que a inflamação aguda tenha inicialmente causado inibição da capacidade imunomoduladora ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The high requirement of the locomotor system of equine athletes often results in small joint injuries that can cause synovial inflammation and release of several inflammatory mediators in the articular microenvironment, leading to the development of osteoarthritis (OA). Mesenchymal stem cells (MSCs) are used in these cases to modify the progression of this disease. This study aimed to verify the behavior of allogeneic synovial membrane derived MSCs (MSCsm) against inflammatory events in acute equine synovitis. Synovitis was induced by the intra-articular (IA) administration of 0.5 ng of LPS and the subjects were treated 8 hours post-induction. The control group received 2 ml of PBS IA as treatment, while the treated group received 107 MSCsm IA. Physical exams, lameness evaluations, cytological analysis of synovial fluid and determination of synovial concentrations of TGF-β and PGE2 were performed. No differences were observed in lameness and physical exam parameters between the groups. Cytological analysis revealed a significant decrease in lymphocytes and macrophages in the treated group (P = 0.0059 and P = 0.0003, respectively), which also had lower levels of TGF-β (P = 0.0467) at 24 h. The other parameters did not present significant difference at any time. Our data suggest that acute inflammation initially caused inhibition of the immunomodulatory capacity of MSCs, which was resumed after 24h with the decline of joint inflammation, and that the interaction of MSCs with th... (Complete abstract click electronic access below) / Mestre
126

Potencial osteogênico in vitro e in vivo de células-tronco mesenquimais de polpa dental e tecido adiposo / In vitro and in vivo osteogenic potential of mesenchymal stem cells from adipose tissue and dental pulp

Ishiy, Felipe Augusto André 27 June 2012 (has links)
Células-tronco humanas derivadas da polpa dental (hDPSCs) e células-tronco humanas derivadas de tecido adiposo (AhSCs) são células multipotentes capazes de diferenciação osteogênica in vitro e in vivo, e promissoras fontes de células para a engenharia de tecido ósseo, dada a sua facilidade de expansão, isolamento e diferenciação. É de grande interesse compreender qual é o melhor tipo celular para diferenciação osteogênica, assim, o objetivo deste estudo foi comparar o potencial de diferenciação osteogênica in vitro e in vivo entre hDPSCs e hASCs. Foram isoladas e estabelecidas seis populações de células-tronco de hDPSCs (entre 7-12 anos) e seis da hASC (de indivíduos com idade entre 30-49 anos). Após a indução in vitro, a diferenciação osteogênica foi comprovado através das colorações de fosfatase alcalina (9 dias) e vermelho de alizarina (14 e 21 dias). A quantificação da mineralização da matriz após 21 dias de diferenciação osteogênica revelou 2,24 mais ossificação das hDPSCs em relação às hASCs. Para realizar o experimento in vivo, foram triados seis biomateriais para verificar qual melhor biomaterial para o nosso modelo, defeito crítico em calvária de Ratos Wistar não imunossuprimidos, com três amostras de hDPSCs. Após 45 dias, CellCeram(TM) exibiu a melhor neoformação óssea in vivo, e foi selecionado para comparar os potenciais osteogênicos in vivo entre hDPSCs e hASCs. Células (10e6) foram associadas a discos de 4,5 mm CellCeram(TM), grupo controle foi realizado através do transplante do biomaterial livre de células. Neoformação óssea foi mensurada 45 dias após a cirurgia através da coloração histológica de hematoxilina / eosina. A formação óssea total foi quantificada através da análise de imagens de todas as ilhas de ossificação. A associação entre hDPSCs e CellCeram(TM) promoveu 7,24 vezes mais neoformação óssea quando comparado com a associação entre esse mesmo material e hASCs (p <0,0001). A utilização de células-tronco adultas para regeneração óssea é uma ótima abordagem para uso terapêutico, e calcular ou predizer o potencial osteogênico das células utilizadas é extremamente importante e necessário para futura aplicação em novas estratégias de bioengenharia de tecido ósseo / Human dental pulp stem cells (hDPSCs) and human adipose-derived stem cells (AhSCs) are multipotent cells capable of undergoing osteogenesis in vitro and in vivo, and promising cell-source populations for bone tissue engineering given their easiness of isolation, expansion and differentiation. It is of great interest to understand which is the best cell type for osteogenic differentiation, thus the aim of this study is to compare the in vitro and the in vivo osteogenic differentiation potentials between DPSCs and ASCs. We isolated six stem cell populations from DPSCs (aged 7-12 years) and six from ASCs (from subjects aged 30-49 years) and cell culture was established. After in vitro induction the populations were able to undergo osteogenic differentiation, as evidenced by alkaline phosphatase (9 days) and alizarin red S (14 and 21 days) stainings. Quantification of matrix mineralization after 21 days of osteogenic differentiation revealed an enhancement of 2.24-fold increase between hDPSCs and hASCs differentiation. To perform the in vivo experiment, we promoted a screening of six scaffolds to find out which would be best scaffold to our model, a calvarial critical-sized defect in Wistar non-immunosuppressed rats, with three different culture samples of hDPSCs. After 45 days, CellCeram(TM) displayed the best in vivo bone neoformation, and was used to compare the in vivo osteogenic potentials between hDPSCs and hASCs. Cells (10e6) were associated to 4.5 mm CellCeram(TM) discs, and control groups were performed transplanting the biomaterial free of cells. Bone healing was measured through histological hematoxylin/eosin staining 45 days after surgery. Newly formed bone was also evaluated by total bone island surface quantification through image analysis. The association between hDPSCs and CellCeram(TM) induced a mean of 7.24 times more bone formation when compared to the association between this same material and hASCs (p<0.0001). The use of adult stem cells for bone regeneration is a robust therapeutic option, and calculate or predicts the osteogenic potential of the cell used are extremely important and necessary to future application, and translation to new strategies in bone tissue engineering
127

Panículo adiposo interescapular de coelho da espécie Oryctolagus cuniculus como fonte de células-tronco / The interscapular adipose tissue from rabbit Oryctolagus cuniculus as a source of stem cells

Fabrício Carvalho Torres 05 June 2009 (has links)
Nos últimos anos, as células-tronco, devido a sua capacidade de originar diversos tecidos corporais e pelo poder de auto-renovação, impulsionaram os estudos de engenharia tecidual, sobretudo em medicina regenerativa. Nesse aspecto, o tecido adiposo vem se mostrando como fonte ideal para obtenção de tais células, devido à facilidade de captação, à baixa morbidade associada ao procedimento e ao elevado rendimento celular. Com o objetivo de estabelecer um modelo experimental versátil e que satisfizesse várias áreas de interesse, propôs-se o coelho Oryctolagus cuniculus como fonte de tecido adiposo. Esse animal apresenta bolsa adiposa interescapular com peso médio de 17,2g, o que corresponde a cerca de 6,6 g/Kg em machos adultos (peso corporal médio de 2590g). A coleta do material foi por meio de lipoaspiração a seco, com cânula de 3,5mm; levou-se em média, 11 minutos para o procedimento, obtendo-se aproximadamente 10 ml de gordura. Após o processamento pela técnica enzimática, em cada mililitro de gordura encontrou-se em média 1x105 células-tronco. O estudo constatou ainda que, por meio da criopreservação em nitrogênio líquido, as células mantinham suas características citométricas após períodos de congelamento que variaram de uma semana a 13 meses. As células apresentaram características de sua indiferenciação, como a expressão dos marcadores de superfície: CD90, 80,6%; HLA-DR, 2,8% e caspase 3, 10,5%. A análise do ciclo celular com 100% de confluência mostrou que 70,8% das células encontravamse quiescentes; 22,1% apoptóticas. As células com alta capacidade replicativa, que corresponde à fase S do ciclo celular, 1,4% e 0,9% encontravam-se em replicação, mostrando que as células-tronco do tecido adiposo, em cultura, não apresentam uma proliferação descontrolada, tendendo a se estabilizar, principalmente quando atingem confluência máxima em monocamada. Todas essas vantagens fazem com que o modelo proposto possa ser facilmente reprodutível, contribuindo para o estudo das células-tronco do tecido adiposo. / In the latest years, the study on tissue engineering, mainly in the area of regenerative medicine, has advanced because the medical community is highly interested in stem cells. This is due to both the potential of these cells to originate any body tissue and their power of self-renewal. Adipose tissue has been used as an ideal source of such cells, due to the simplicity of their collection, high cellular yield, and low morbidity associated with the procedure. In order to establish a versatile experimental model, which could meet the needs of researchers from various areas, the rabbit Oryctolagus cuniculus was proposed as a source of adipose tissue. This animal has an adipose pad in the interscapular region with an average weight of 17.2g, which corresponds to about 6.6g of fat material per kilogram of an adult male animal (mean body weight = 2.6kg). The material was collected by means of a liposuction procedure. Using a 3.5- mm diameter tube, a volume of nearly 10ml of fat material was obtained in a mean time of 11min. After processing the fat tissue by enzymatic technique, about 1x105 stem cells were found per milliliter of fat material. Using cryopreservation of the cells by freezing them in liquid nitrogen, it was observed that the cytometric characteristics were maintained after a period of time ranging from 1 week to 13 months. The cells presented evident characteristics of undifferentiation, such as expression of the surface markers CD90, HLA-DR, and Caspase-3 (80.6, 2.8, and 10.5 %, respectively). Analysis of the cellular cycle with 100% confluence allowed us to show that 70.8% of the cells were quiescent, 22.1% were apoptotic, 1.4% had high replication capacity (phase S of the cellular cycle) and 0.9% were already in replication (phase G2/M), indicating that stem cells from adipose tissue did not show uncontrolled proliferation, tending to stabilize, mainly when they reach maximal confluence in monolayer. These advantages make this model easily reproducible, facilitating the study of adipose tissue stem cells.
128

Manejo de dentes permanentes com rizogênese incompleta e necrose pulpar / Managing immature necrotic permanent teeth

Nicoloso, Gabriel Ferreira January 2017 (has links)
A perda da vitalidade pulpar, em consequência de injurias traumáticas, lesões cariosas profundas e malformações dentárias, pode interromper o desenvolvimento radicular em dentes permanentes jovens. O tratamento endodôntico em dentes com rizogênese incompleta constituise num desafio ao clínico para a realização de tratamentos convencionais, devido principalmente à dificuldade de debridamento das paredes dentinárias e do adequado selamento apical. Além disso, em função das paredes dentinárias delgadas e uma proporção coroa-raiz inadequada, a ocorrência de fraturas no trans e pós-operatório não é um evento raro. Existem diferentes estratégias terapêuticas para o manejo destes dentes com rizogênese incompleta, incluindo os procedimentos de apicificação e revascularização da polpa. O objetivo desta tese foi revisar sistematicamente a literatura para avaliar a efetividade dos procedimentos de apicificação e revascularização da polpa em relação aos desfechos clínicos, radiográficos e de retenção dentária. Dois revisores de maneira independente revisaram a literatura e avaliaram os artigos. A busca foi realizada na literatura via PubMed/MEDLINE e Embase até junho de 2017 para selecionar estudos de caso-controle e coorte. Um total 231 artigos foram localizados nas bases de dados, dos quais 3 permaneceram após a aplicação dos critérios de elegibilidade. Após a seleção dos artigos, os dados de cada estudo foram coletados e o risco de viés avaliado. Foram obtidas estimativas de efeito comparando o sucesso clínico e radiográfico e retenção dentária entre o plug apical de agregado de trióxido mineral (MTA) versus revascularização da polpa (BC) e hidróxido de cálcio (CH). As duas meta-análises comparando tanto o MTA vs BC para os desfechos clínicos e radiográficos (Z=0.164, p=0.869, RR=1.010, 95%CI:0.895-1.140, I=0%) e retenção dentária (Z=0.855, p=0.393, RR=1.050, 95%CI:0.939-1.173, I=0%) ou MTA vs CH para os desfechos clínicos e radiográficos e retenção dentária (Z=-1.596, p=0.110, RR=0.816, 95%CI:0.635-1.048, I=0%) não demonstraram diferenças estatisticamente significativas. Todos estudos incluídos na revisão sistemática foram considerados de alta qualidade metodológica. Em conclusão, a técnica de revascularização da polpa, por possibilitar o desenvolvimento radicular adicional, deve ser a primeira opção de tratamento em dentes permanentes com rizogênese incompleta que apresentem proporção coroa-raiz inadequada, entretanto, o plug apical de MTA parece apresentar resultados mais fidedignos em relação ao sucesso em geral, e assim, nos casos de dentes permanentes que apresentem proporção coroaraiz satisfatória, esta técnica de ser a primeira opção de tratamento. / The loss of pulp vitality, as a consequence of traumatic injuries, deep carious lesions and dental malformations, may interrupt the root development in young permanent teeth. The endodontic treatment in immature teeth constitutes a challenge to the practitioner to perform conventional treatments, mainly due to difficulty of dentinal walls debridement and adequate apical sealing. In addition, due to the thin dentinal walls and inadequate crown-root proportion, occurrence of trans and postoperative fractures is not a rare event. There are different therapeutic strategies to manage these immature teeth including apexification and pulp revascularization procedures. The aim of this thesis was to systematically review the literature to evaluate the effectiveness of apexification and pulp revascularization procedures regarding the clinical, radiographic and tooth retention outcomes. Two reviewers independently performed the screening and evaluation of articles. The literature was screened via PubMed/MEDLINE and Embase databases until June 2017 to select case-control and cohort studies. A total of 231 articles were retrieved from the databases, in which only 3 remained after the eligibility criteria. After the selection of the articles, the data of each study was extracted and bias risk assessed. Pooled-effect estimates were obtained comparing the clinical and radiographic success and retention rates among the mineral trioxide aggregate (MTA) apical plug vs pulp revascularization (BC) and calcium hydroxide (CH). The two meta-analysis comparing either MTA vs BC for clinical and radiographic outcomes (Z=0.164, p=0.869, RR=1.010, 95%CI:0.895-1.140, I=0%) and tooth retention rates (Z=0.855, p=0.393, RR=1.050, 95%CI:0.939-1.173, I=0%) or MTA vs CH for clinical and radiographic outcomes and tooth retention rates (Z=-1.596, p=0.110, RR=0.816, 95%CI:0.635-1.048, I=0%) showed no statistically significant differences. All studies included in the systematic review were classified as high quality. In conclusion, the revascularization treatment, as it allows additional root development may be the first treatment option in immature necrotic permanent teeth that have inadequate crown-root ratio, however, the MTA apical plug seems to provide more predictable outcomes regarding the overall success, and thus, in cases of permanent teeth having adequate crown-root proportion, it should be the first treatment option.
129

Predicting regenerative chatter in turning using operational modal analysis

Kim, Sooyong 23 April 2019 (has links)
Chatter, unstable vibration during machining, damages the tool and workpiece. A proper selection of spindle speed and depth of cut are required to prevent chatter during machining. Such proper cutting conditions are usually determined using vibration models of the machining process. Nonetheless, uncertainties in modeling or changes in dynamics during the machining operations can lead to unstable machining vibrations, and chatter may arise even when stable cutting conditions are used in the process planning stage. As a result, online chatter monitoring systems are key to ensuring chatter-free machining operations. Although various chatter monitoring systems are described in the literature, most of the existing methods are suitable for detecting chatter after vibrations become unstable. In order to prevent poor surface finish resulting from chatter marks during the finishing stages of machining, a new monitoring system that is capable of predicting the occurrence of chatter while vibrations are still stable is required. In this thesis, a new approach for predicting the loss of stability during stable turning operations is developed. The new method is based on the identification of the dynamics of self-excited vibrations during turning operations using Operational Modal Analysis (OMA). The numerical simulations and experimental results presented in this thesis confirm the possibility of using Operational Modal Analysis as an online chatter prediction method during stable machining operations. / Graduate
130

Development of a 3D tissue engineered skeletal muscle and bone pre-clinical co-culture platform

Wragg, Nicholas M. January 2016 (has links)
Pre-clinical studies are a necessary step in the process of material and drug testing. For this, high-throughput monolayer cell cultures are conducted followed by in vivo animal experiments. However, animal use is ethically questionable and in many cases yields misleading results. In vitro three dimensional (3D) tissue engineered (TE) structures have been shown to better represent in vivo tissue morphology and biochemical pathways than monolayer cultures and are less ethically questionable than animal models. Therefore, an in vitro biomimetic musculoskeletal junction (MSKjct) is required as a more relevant pre-clinical testbed. This thesis describes the steps taken to co-culture 3D TE skeletal muscle and bone models as a material testbed and towards an in vitro MSKjct.

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