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Elshami, Marrow. "Micro-leakage and Enamel demineralisation : a comparative study of three different adhesive cements." University of the Western Cape, 2016. http://hdl.handle.net/11394/5607.
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Magister Scientiae Dentium - MSc(Dent)<br>Introduction: Micro-leakage and enamel demineralization is still a major challenge in dental practice. It can lead to formation of demineralization lesions around and beneath the adhesive–enamel interface (Mali et al., 2006). Enamel demineralization adjacent to orthodontic brackets is one of the risks associated with orthodontic treatment. The prevention of demineralization during orthodontic treatment is therefore essential for aesthetic reasons and to circumvent the onset of caries. Aim: To assess micro-leakage and enamel demineralization around orthodontic direct attachments (brackets) using three different orthodontic cements. Materials and methods: In this in-vitro study, intact (non carious) extracted human premolars were used to compare the micro-leakage and enamel demineralization of three different cements (Fuji Ortho LC, Rely X luting 2 and Transbond XT). The dye penetration technique was used to evaluate micro-leakage on extracted human premolars. Micro-hardness testing was performed on 21 teeth to determine enamel demineralization. Sixty teeth were randomly divided into 3 groups of twenty teeth each. Direct attachments were cemented on each tooth using 3 different cements; Fuji Ortho LC (GC Fuji II LC GC Corporation Tokyo, Japan), (group 1), Rely X luting 2 cement (3M ESPE dental product, USA), (group 2), Transbond XT Light Cure (3M Unitek, Monrovia, Calif), (group 3). After the orthodontic direct attachments were fitted, they were exposed to 500 thermo-cycles between 5°C and 55°C, with a dwell time of 15 seconds in a buffered (pH 7) 1% methylene blue dye solution (Grobler et al, 2007). The specimens were viewed under a stereomicroscope (Nikon, Japan) at magnification of 40 times. Photographs of each specimen were taken with a Leica camera (Leica DFC 290 micro-systems, Germany) fitted onto a stereomicroscope. The ACDsee photo editing programme was used to transfer the photographs to a computer to measure the dye penetration along the enamel–adhesive and adhesive–bracket interfaces, both on the gingival and occlusal edge at × 40 magnification. For the demineralization sample, 21 teeth were divided into 3 groups of seven teeth each, where direct attachments were cemented using each of the 3 cements, group 1, Fuji Ortho LC (GC Fuji II LC GC Corporation Tokyo, Japan); group 2, Rely X luting 2 cement (3M ESPE dental product, USA) and group 3, Transbond XT Light Cure (3M Unitek, Monrovia, Calif). A digital hardness tester with Vickers diamond indenter (Zwick RoellIndentec (ZHV; Indentec UK) was used to measure surface micro-hardness of enamel before and after attaching the brackets. Ten indentations were made on the enamel surface of each tooth before bonding the brackets with a 300g load applied for 15 seconds to establish the baseline hardness value. After de-bonding the brackets, the hardness was measured again in the same area as mentioned above to determine the degree of enamel demineralization (softening). Result: The result showed statistically significantly lower levels of micro-leakage for Transbond XT (P= <0.001). The amount of micro-leakage on the margins was significantly higher in the gingival portion (P <0.05) as compared with the occlusal margin. Enamel micro-hardness tests before bonding using the three different cements showed that the variances are not significantly different (Chi-squared = 3.051, df = 2, p-value = 0.218). However, the micro-hardness tests done after bonding and thermo-cycling was statistically significantly different (Chi-squared = 13.435, df = 2, p-value = 0.001). Clearly, the Transbond XT group had less hardness, implying greater demineralization than the Fuji Ortho LC and Rely X luting 2 groups. Two sample t-tests show that mean value for the Fuji Ortho and Rely X luting 2 were not significantly different from each other (t = -0.636, df = 12, p-value = 0.537). The mean value for Transbond XT differed significantly from both the other two means: Transbond XT vs Fuji Ortho LC (t = 3.249, df = 6.9, p-value = 0.014). Transbond XT vs Rely X luting 2 (t = 3.493, df = 6.8, p-value = 0.011). Conclusions: This study showed that Fuji Ortho LC and Rely X luting 2 show more micro-leakage than Transbond XT. However Transbond XT had significant lower micro-leakage, less hardness (greater demineralization) than the Fuji Ortho LC and Rely X luting 2. This may have been due to the fluoride release which significantly reduces demineralization. Therefore the Fuji Ortho LC and Rely X luting 2 may be recommended for prevention of demineralization during orthodontic treatment.
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Manni, Hassan. "An in vitro study of post-restorative bleaching : effect on microleakage." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1776_1307617941.
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<p>Aim and Objectives: To assess the effect of bleaching on the marginal integrity of Class V composite resin restorations. To determine the effect of a 6% hydrogen peroxide over the counter and a 38% hydrogen peroxide in-office vital bleaching treatment products on the microleakage of Class V composite restorations.</p>
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Knorr, Fanny Esther [Verfasser]. "Follicular penetration of nano-sized particulate FA-PLGA and the dye RhBITC in dorsal dog and rat skin, and porcine ear skin as an in vitro model for the human integument / Fanny Esther Knorr." Berlin : Freie Universität Berlin, 2011. http://d-nb.info/1025356039/34.
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Clotten, Stefan. "Der Einfluss einer vereinfachten Applikationstechnik auf das Randverhalten von Keramikinlays." Doctoral thesis, [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=970193483.
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Serôdio, Maria Serra Ribeiro. "Estudo comparativo da micro-infiltração apical em ápices abertos com recurso a 3 técnicas de obturação." Master's thesis, [s.n.], 2015. http://hdl.handle.net/10284/5105.
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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária<br>Introdução: O momento da obturação do sistema canalar é uma das etapas mais importantes no tratamento Endodôntico, sendo que 60% dos insucessos Endodônticos são responsáveis à inadequada obturação. O principal objectivo da obturação é o preenchimento tridimensional do canal radicular eliminando os espaços vazios anteriormente ocupados pelos tecidos pulpares.
Devido a um selamento apical inadequado no momento da obturação, os microorganismos remanescentes dentro do canal radicular podem desencadear uma micro-infiltração apical.
Sendo que a micro-infiltração é influenciada por diferentes técnicas de obturação e por diferentes materiais obturadores, neste estudo pretendeu-se avaliar qual a técnica e o material que apresenta menor micro-infiltração apical em raízes com ápices abertos.
Objectivos: Este estudo tem como objectivo avaliar in vitro a micro-infiltração apical em ápices abertos, calibrados aproximadamente a 70, recorrendo a três diferentes técnicas de obturação.
Materiais e Métodos: Neste estudo foram utilizados 66 dentes monocanalares, sendo os quais foram divididos aleatoriamente em 5 grupos. Todos os dentes foram instrumentados recorrendo ao sistema Reciproc® e Profile® a fim de alcançar aproximadamente o calibre 70. O grupo I (20 dentes) foi obturado com a técnica de condensação lateral a frio, o grupo II (20 dentes) foi obturado recorrendo ao System B e, por úlitmo, o grupo III (20 dentes)foi obturado com MTA. Os dois grupos restantes grupos, são os grupos controle positivo e negativo (3 dentes + 3 dentes), os quais foram utilizados com o objectivo de atestar a ocorrência de micro-infiltração apical. O método de penetração de corante, foi o método eleito recorrendo ao corante Azul-De-Metileno a 2% para avaliar a micro-infiltraçao apical nas diferentes técnicas de obturação. Resultados: No grupo IV (controlo positivo) o corante infiltrou no comprimento total do dente, por outro lado, no grupo V (controlo negativo) não houve infiltração em nenhuma área da raiz.
O Grupo I apresenta uma micro-infiltração média de 2,5, o Grupo II de 0,6 e o Grupo III 0,4. Em relação ao desvio padrão, os valores são os seguintes: o Grupo I apresenta 1,4, o Grupo II 0,5 e o Grupo III 0,7.
Pode verificar-se a existência de algumas diferenças estatisticamente significativas (p<0.001) entre o Grupo I e II, assim como, o Grupo I e III. No entanto, verificou-se que não existem diferenças estatisticamente (p<0,05) entre o Grupo II e III.
Conclusões: Após a recolha e análise dos dados conclui-se neste estudo que o MTA foi o grupo que apresentou melhores resultados, ou seja, a menor infiltração apical seguindo-se do grupo do System B e, por último, o grupo da Condensação Lateral a Frio. Introduction: The root filling moment is one of the most important steps in Endodontic treatment, 60% of endodontic failures are due to inadequate filling. The main purpose of obturation is the three-dimensional root canal filling eliminating voids previously occupied by pulpal tissues.
Due to inappropriate apical sealing during obturation, the remaining microorganisms in the root canal can promote microleakage.
As microleakage is influenced by different obturation techniques and different filling materials, this study aimed to evaluate which technique and material shows the lower apical microleakage in roots with open apexes.
Aim: This study aims to evaluate in vitro the apical microleakage on open apices, calibrated approximately at 70, using three different obturation techniques.
Materials and Methods: In these study 66 monocanalares tooth were used, in which were randomly divided into 5 groups . All teeth were instrumented using the Reciproc® system and Profile® system in order to achieve approximately the gauge 70. The group I (20 teeth) were filled with Cold Lateral Condensation , group II (20 teeth) was filled using the System B , and for last, group III (20 teeth) was filled with MTA. The remaining two groups groups are the positive and negative control groups (3 teeth+3 teeth), which were used in order to certify the occurrence of apical microleakage . The dye penetration method , was the chosen method using Methylene Blue dye at 2% to assess the apical microleakage in different filling techniques.
Results: In Group IV (positive control) the dye infiltrated the entire length of the tooth, on the other hand, in Group V (negative control) there was no infiltration in any area of the root.
Group I shown a microleakage average of 2.5 microleakage, Group II 0.6 and Group III 0.4. Regarding the standard deviation, the values are as follows: Group I has 1.4, Group II 0.5 and Group III 0.7. We can assure the existence of some statistically significant differences (p < 0.001 ) between the groups I and II , as well as Group I and III . However , there was no statistically differences (p < 0.05) in group II and III.
Conclusion: After collecting data and deep analysis, we concluded that the MTA group shown the best results, in other words, the group with the least apical microleakage followed by the System B group and, finally, Cold Lateral Condensation group.
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Ding, Xiaoyu. "Applied study and modeling of penetration depth for slot die coating onto porous substrates." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53425.
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A distinctive field in the coatings industry is the coating of porous media, with broad applications in paper, apparel, textile, electronics, bioengineering, filtration and energy sector. A primary industrial scale process that can be used to coat porous media in a fast and flexible manner is slot die extrusion. A major concern when coating porous media with a wetting fluid is fluid penetration into the substrate. Although some level of penetration is desirable to obtain specific material properties, inadequate or excessive fluid penetration can negatively affect the strength, functionality or performance of the resulting material. In spite of its apparent industrial importance, limited modeling and experimental work has been conducted to study fluid penetration into porous media during fabrication. The effects of processing parameters on the penetration depth, the effects of penetration on material quality, and the method to predict and control the penetration depth are not well understood. This dissertation is composed of two parts.
Part I is an applied study for coating onto porous media. This part focuses on the first objective of this dissertation which is to elucidate clearly the feasibility, advantages and disadvantages of the direct coating method as a potential fabrication route for membrane electrode assembly (MEA). MEA samples are fabricated using both traditional and the direct coating methods. Then, the quality and performance of the MEA samples are examined. Experimental results in Part I demonstrate that it is feasible to fabricate MEAs using the direct coating method. However, Nafion® solution penetrates into the catalyst layer during the coating process and causes lower performance of fuel cells, which is the motivation for Part II of this thesis.
The objective of Part II is to fundamentally understand the fluid penetration process and predict the penetration depth when directly coating porous media, using a comprehensive approach. A series of computational and analytical models are developed to predict the penetration depth for both Newtonian and non-Newtonian fluids with or without capillary pressure. Finally the accuracy of developed models are validated through experiments. The relative error between the predicted and experimentally measured penetration depth is generally lower than 20%.
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Baek, Seong-Ho. "Penetration of buoyancy driven current due to a wind forced river plume." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1174.
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Olsen, Gregory Dana. "Experimental investigation into catastrophic failure of pressure vessels due to hypervelocity impact /." Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3008411.
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Pitman, Lacey. "GROUND-PENETRATING RADAR IMAGES OF A DYE TRACER TEST WITHIN THE UNSATURATED ZONE AT THE SUSQUEHANNA-SHALE HILLS CZO." Master's thesis, Temple University Libraries, 2014. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/306057.
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Geology<br>M.S.<br>Dye tracer and time-lapse ground-penetrating radar (GPR) were used to image preferential flow paths in the shallow, unsaturated zone on hillslopes in two adjacent watersheds within the Susquehanna-Shale Hills Critical Zone Observatory (CZO). At each site we injected about 50 L of water mixed with brilliant blue dye (4 g/L) into a trench cut perpendicular to the slope (~1.0 m long by ~0.20 m wide by ~0.20 m deep) to create a line of infiltration. GPR (800 MHz antennae with constant offset) was used to monitor the movement of the dye tracer downslope on a 1.0 m x 2.0 m grid with a 0.05 m line spacing. The site was then excavated and the stained pathways photographed to document the dye movement. We saw a considerable difference in the pattern of shallow preferential flow between the two sites despite similar soil characteristics and slope position. Both sites showed dye penetrating down to saprolite (~0.40 m); however, lateral flow migration between the two sites was different. At the Missed Grouse field site, the lateral migration was ~0.55 m as an evenly dispersed plume, but at distance of 0.70 m a finger of dye was observed. At the Shale Hills field site, the total lateral flow was ~0.40 m, dye was barely visible until the excavation reached ~0.10 m, and there was more evidence of distinct fingering in the vertical direction. Based on laboratory and field experiments as well as processing of the radargrams, the following conclusions were drawn: 1) time-lapse GPR successfully delineated the extent of lateral flow, but the GPR resolution was insufficient to detect small fingers of dye; 2) there was not a distinct GPR reflection at the regolith-saprock boundary, but this interface could be estimated from the extent of signal attenuation; 3) the preliminary soil moisture conditions may explain differences in the extent of infiltration at the two sites; 4) rapid infiltration into the underlying saprock limited the extent of shallow lateral flow at both sites and can be seen using the mass balance calculation and the lateral extent of dye within the radargrams; and 5) variations in flow patterns were observed between sites with similar settings at Susquehanna-Shale Hills CZO.<br>Temple University--Theses
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Forsell, Caroline. "Numerical simulation of failure response of vascular tissue due to deep penetration." Licentiate thesis, KTH, Biomekanik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-30875.
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Sangtian, Note. "Miniature piezocene tests and effects of smear due to vertical penetration in layered soils." Thesis, University of Sheffield, 2001. http://etheses.whiterose.ac.uk/10261/.
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Knowledge of the soil profile is necessary for ground engineering projects and piezocones are widely used in situ test devices that can supply some of this knowledge. This thesis describes an investigation of the performance of a specific piezocone when used in thinly layered soil. A miniature piezocone, with a cross sectional area of 1 cm2, was driven at a speed of 20mm/sec into artificial layered soil samples that were constructed in the laboratory and consolidated under a vertical pressure in a 254mm diameter test cell. The layered samples contained alternating layers of pre-consolidated Speswhite kaolin clay about 20mm thick and layers of more permeable, silty or sandy soil about 2mm thick. The pore pressure filter of the piezocone was located either at the cone tip or cone shoulder. During driving, the cone resistance and pore pressure responses were recorded at a rate of at least 200 readings/sec. Once the piezocone was stopped, in a clay layer, the dissipation of excess pore water pressure was monitored. In terms of the pore pressure response, though not the cone resistance, the piezocone was able to detect the more permeable layers located between the clay layers. Both dilation and localised drainage in the more permeable layers, deformed during penetration, could have significantly influenced the pore pressure responses. Despite the proximity of permeable layers, values of the coefficient of consolidation obtained from pore pressure dissipation at the piezocone tip agreed fairly well with values obtained independently during unloading or reloading of the clay in one-dimensional consolidation tests. At the cone shoulder, the permeable layers had some influence and larger values were obtained. The layered soil samples used for piezocone testing were also used for investigating the effects of soil disturbance, or "smear", caused by vertical penetration of objects with different sectional shapes in the context of permeability measurement and soil drainage. A mandrel carrying a vertical drain, either circular (23.5mm diameter) or rectangular (50x6.5mm) in section, was driven into the centre of the soil sample at a speed of 5mm/sec. The effects of smear were evaluated by performing radial flow permeability tests in which pressure distributions across sample were recorded. The effect of smear increased substantially as the permeability of the more permeable layers increased, but only when it exceeded the permeability of the clay by a factor of about 100. For a given layer combination, the rectangular drain always produced a significantly smaller smear effect than the circular drain.
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Korte, David M. "Three Dimensional Analysis of a Proglacial Clastic Dyke Network Using Ground Penetrating Radar, Skeidararsandur, Iceland." Kent State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=kent1381872414.
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Jacob, Toni Alexander [Verfasser]. "Bedeutung des Transporterproteins MRP2 für die Penetration von ATI-Rezeptorantagonisten durch die Blut-Hirn-Schranke / Toni Alexander Jacob." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1149050365/34.
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Schmedt, auf der Günne Wenke [Verfasser]. "Omapatrilat : zentrale Effekte und die Penetration durch die Blut-Hirn-Schranke bei der Ratte / Wenke Schmedt auf der Günne." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1141678012/34.
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Shao, Shengnan. "An Approach to Demand Response for Alleviating Power System Stress Conditions due to Electric Vehicle Penetration." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/29335.
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Along with the growth of electricity demand and the penetration of intermittent renewable energy sources, electric power distribution networks will face more and more stress conditions, especially as electric vehicles (EVs) take a greater share in the personal automobile market. This may cause potential transformer overloads, feeder congestions, and undue circuit failures.
Demand response (DR) is gaining attention as it can potentially relieve system stress conditions through load management. DR can possibly defer or avoid construction of large-scale power generation and transmission infrastructures by improving the electric utility load factor. This dissertation proposes to develop a planning tool for electric utilities that can provide an insight into the implementation of demand response at the end-user level. The proposed planning tool comprises control algorithms and a simulation platform that are designed to intelligently manage end-use loads to make the EV penetration transparent to an electric power distribution network. The proposed planning tool computes the demand response amount necessary at the circuit/substation level to alleviate the stress condition due to the penetration of EVs. Then, the demand response amount is allocated to the end-user as a basis for appliance scheduling and control.
To accomplish the dissertation objective, electrical loads of both residential and commercial customers, as well as EV fleets, are modeled, validated, and aggregated with their control algorithms proposed at the appliance level.
A multi-layer demand response model is developed that takes into account both concerns from utilities for load reduction and concerns from consumers for convenience and privacy. An analytic hierarchy process (AHP)-based approach is put forward taking into consideration opinions from all stakeholders in order to determine the priority and importance of various consumer groups.
The proposed demand response strategy takes into consideration dynamic priorities of the load based on the consumersâ real-time needs. Consumer comfort indices are introduced to measure the impact of demand response on consumersâ life style. The proposed indices can provide electric utilities a better estimation of the customer acceptance of a DR program, and the capability of a distribution circuit to accommodate EV penetration.
Research findings from this work indicate that the proposed demand response strategy can fulfill the task of peak demand reduction with different EV penetration levels while maintaining consumer comfort levels. The study shows that the higher number of EVs in the distribution circuit will result in the higher DR impacts on consumersâ comfort. This indicates that when EV numbers exceed a certain threshold in an area, other measures besides demand response will have to be taken into account to tackle the peak demand growth.
The proposed planning tool is expected to provide an insight into the implementation of demand response at the end-user level. It can be used to estimate demand response potentials and the benefit of implementing demand response at different DR penetration levels within a distribution circuit. The planning tool can be used by a utility to design proper incentives and encourage consumers to participate in DR programs. At the same time, the simulation results will give a better understanding of the DR impact on scheduling of electric appliances.<br>Ph. D.
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Schuster, Sven Ole [Verfasser]. "Untersuchung der Bedeutung des P-Glykoproteins für die Penetration von AT1-Rezeptorantagonisten durch die Blut-Hirn-Schranke / Sven Ole Schuster." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1147380228/34.
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Bian, Yuankai. "Analysis and mitigation of the low inertia challenges due to the high renewable penetrations." Thesis, University of Bath, 2019. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.767612.
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The power system inertia refers to the stored kinetic energy in all synchronous rotating elements, which determines the stability of system frequency as it is the initial resistance to any frequency deviations caused by the generation failure, generation shortfall, a sudden load increase. The integration of the asynchronous renewable generations reduces the overall system inertia thus introduces new challenges for maintaining the stability of system frequency. For a conventional generation dominated system, frequency stability is ensured by the adequate frequency response. However, for a renewable dominated system, the same frequency response reserve is unable to guarantee the frequency stability due to the reduced inertia. When there is a sudden load/generation imbalance, the consequences of the reduced inertia on the system operation are the rapid change in frequency, the potential hazards of the higher rate of change of frequency (ROCOF) to trip the ROCOF-based protection relays for the distributed generators, and the significant frequency drop causing unintentional low-frequency demand disconnection. Due to the reduced inertia, the system operation planning is shifting from efficiency driven to the balance between efficiency and stability, which is commonly investigated in the unit commitment (UC) to determine the optimal generation scheduling. The existing research in addressing the reduced inertia issues from the perspective of UC optimisation only considers the ROCOF requirements for inertia and ignores the requirements for the maximum frequency drop allowed due to the lack of the representation for the frequency dynamics. The UC is a mixed-integer problem and the transcendental relationship between inertia and the minimum frequency raises the difficulty to not only implement the inertia-related constraint into the UC consideration but also solve the mixed-integer nonlinear-constrained problem. Further challenges from considering the inertia-related constraints into UC is to bring finical incentives for the generator with low output and high inertia contributions. For the current practice, the inertia is provided voluntarily and the significance of inertia is not reflected and rewarded. This thesis aims to address the challenges of the system operation planning and the market incentives. For the operation planning perspective firstly a frequency mathematical model is proposed that can analyse the representation of the frequency transient dynamics for the initial ROCOF, the minimum frequency and the quasi-steady-state frequency during contingencies; secondly the frequency-related constraints are incorporated into the UC generation scheduling problem for the system operation planning while ensuring the stability of system frequency. Finally, an inertia market is developed for the inertia providers to reward with an incentive for the provision of inertia based on the UC optimisation results.
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Ying, Shaoqing [Verfasser], and Harald [Akademischer Betreuer] Schwarz. "Auswirkungen auf die Niederspannungsnetze bei hoher Penetration von innerstädtischen Photovoltaikanlagen und Elektrofahrzeugen / Shaoqing Ying. Betreuer: Harald Schwarz." Cottbus : Universitätsbibliothek der BTU Cottbus, 2012. http://d-nb.info/1021685615/34.
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Ghosh, Shibani. "A Real-time Management of Distribution Voltage Fluctuations due to High Solar Photovoltaic (PV) Penetrations." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/74424.
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Due to the rapid growth of grid-tied solar photovoltaic (PV) systems in the generation mix, the distribution grid will face complex operational challenges. High PV penetration can create overvoltages and voltage fluctuations in the network, which are major concerns for the grid operator. Traditional voltage control devices like switched capacitor banks or line voltage regulators can alleviate slow-moving fluctuations, but these devices need to operate more frequently than usual when PV generation fluctuates due to fast cloud movements. Such frequent operations will impact the life expectancy of these voltage control devices.
Advanced PV inverter functionalities enable solar PV systems to provide reliable grid support through controlled real injection and/or reactive power compensation. This dissertation proposes a voltage regulation technique to mitigate probable impacts of high PV penetrations on the distribution voltage profile using smart inverter functionalities. A droop-based reactive power compensation method with active power curtailment is proposed, which uses the local voltage regulation at the inverter end. This technique is further augmented with very short-term PV generation forecasts. A hybrid forecasting algorithm is proposed here which is based on measurement-dependent dynamic modeling of PV systems using the Kalman Filter theory. Physical modeling of the PV system is utilized by this forecasting algorithm. Because of the rise in distributed PV systems, modeling of geographic dispersion is also addressed under PV system modeling.
The proposed voltage regulation method is coordinated with existing voltage regulator operations to reduce required number of tap-change operations. Control settings of the voltage regulators are adjusted to achieve minimal number of tap-change operations within a predefined time window. Finally, integration of energy storage is studied to highlight the value of the proposed voltage regulation technique vis-à-vis increased solar energy use.<br>Ph. D.
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Paris, Anja [Verfasser]. "Einfluss der Konditionierung mit verschiedenen Säuregelen auf die Penetration eines Adhäsivs in natürliche Zahnschmelzkaries in vitro / Anja Paris." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023710374/34.
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Rettkowski, Udo. "Einfluss von ausgewählten Cyclodextrinen auf die corneale Metabolisierung und auf das Penetrations- und Permeationsverhalten von Dipivefrin." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968860877.
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Rettkowski, Udo. "Einfluss von ausgewählten Cyclodextrinen auf die corneale Metabolisierung und auf das Penetrations- und Permeationsverhalten von Dipivefrin." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2003. http://dx.doi.org/10.18452/14913.
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Ziel der vorliegenden Arbeit war die Untersuchung des Einflusses von ausgewählten Cyclodextrinen (alpha-, HP-alpha-, beta-, HP-beta, gamma- und HP-gamma-Cyclodextrin) als Hilfsstoffe in Ophthalmika auf die enzymatische Esterspaltung von Dipivefrin im Corneaepithel. Dazu waren neben der Betrachtung der enzymatischen Spaltung von Dipivefrin durch corneale Enzyme von Rinderaugen und dem Reinenzym Butyrylcholinesterase Untersuchungen zu den Wechselwirkungen von Dipivefrin mit den verwendeten Cyclodextrinen und dem cornealem Gewebe notwendig. Zur Charakterisierung der Dipivefrin/Cyclodextrin-Wechselwirkungen in wässriger Lösung wurden die Ultrafiltration, die Hochleistungs-Flüssigchromatographie und die UV- bzw. H-NMR-Spektroskopie eingesetzt. Die Ermittlung der Dipivefrin- bzw. Cyclodextrin-Wechselwirkung mit dem cornealen Gewebe erfolgte mittels Thermoanalytik und Elektronenmikroskopie. Der Einfluss ausgewählter Cyclodextrine auf die in-vitro-Permeation von Dipivefrin durch die Schweinecornea und auf die dabei im Corneaepithel stattfindende enzymatische Freisetzung von Epinephrin wurde untersucht. Mit Hilfe einer Druckpermeationszelle wurde der Einfluss von Dipivefrin bzw. in Kombination mit alpha- und beta-Cyclodextrin auf die forcierte Permeation von Wasser durch die Cornea von endothelial nach epithelial untersucht und die Modelldaten auf den physiologischen Druck des Auges umgerechnet.<br>The aim of the present work was to study the influence of different (cyclodextrins alpha-, HP-alpha-, beta-, HP-beta-, gamma- und HP-gamma-cyclodextrin) as components of eye drops on the enzymatic hydrolysis of dipivefrine in the corneal epithelium. Therefor, enzymatic degradation of dipivefrine by corneal enzymes of bovine eyes and by the purified enzyme butyryl cholinesterase was investigated. The interaction of dipivefrine with cyclodextrins was tested in aqueous solution by the use of ultrafiltration, high performance liquid chromatography, UV- and H-NMR-spectroscopy. The interaction of dipivefrine with corneal tissue was tested by the use of thermal analysis and electron microscopy. The influence of some cyclodextrins on the in-vitro permeation of dipivefrine through porcine cornea and the simultaneous enzymatic release of epinephrine in the corneal epithelium was investigated. The forced permeation of water through cornea from the endothelial to epithelial site was tested with help of a pressurized permeation device and the modell data were calculated to meet the physiological pressure in the eye.
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KUNIEDA, Minoru, Keisuke KAWAMURA, Hikaru NAKAMURA, and Khoa K. TRAN. "QUANTITATIVELY EVALUATION OF CRACK PROPAGATION DUE TO REBAR CORROSION." 日本コンクリート工学会, 2010. http://hdl.handle.net/2237/20926.
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Van, Dyk Christina Petronella. "Transdermal delivery of 5-Fluorouracil with PheroidTM technology / C.P. van Dyk." Thesis, North-West University, 2008. http://hdl.handle.net/10394/1905.
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Roshan, Arman. "Different Approaches to Model Cover-Cracking of RC Structures due to Corrosion." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37104.
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This thesis presents three different approaches to model corrosion-induced crack propagation in reinforced concrete structures. The first approach is solved numerically using finite differences to model the softening behaviour of concrete in tension. The second approach idealizes the concrete cover as either a brittle elastic or an elastoplastic material so that it may be solved using a closed-form solution. Both approaches are based on a thick-walled cylinder (TWC) analogy and consider rust compressibility and rust diffusion into cracks. The third approach uses finite element modelling to validate the application of the TWC and perform a parametric study. The results obtained using each approach are compared against each other as well as against experimental results. The TWC was found to be an appropriate analogy for the geometries and reinforcement configurations considered. Analytical models were found to provide upper and lower limits to the results based on the numerical model. The experimental data found in the literature showed reasonable agreement with predictions from the numerical and elastoplastic models.
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Nightingale, Sam. "The role of the central nervous system as a sanctuary site for HIV due to limited penetration of antiretroviral drugs." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2013319/.
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Introduction. HIV-associated neurocognitive disorders appear to remain common despite access to antiretroviral therapy (ART). Penetration of ART into the central nervous system (CNS) is highly variable between drugs and between individuals. Cerebrospinal fluid (CSF) concentrations of many antiretroviral medications fall below the minimum inhibitory concentration for wild type virus. HIV-1 RNA can be detected in the CSF at greater levels than in plasma (CSF/plasma discordance), however the clinical significance of this is unclear, and the degree of difference considered pathological varies. Whether the CNS can act as a sanctuary site leading to persistent HIV detection in plasma is not known. Methods. The PARTITION study recruited HIV positive adults from 13 UK clinical sites. Paired CSF and plasma was collected from patients undergoing LP for clinical indication (group A) and subjects with unexplained viraemia despite ART (group B). The study aimed to determine a) the prevalence of CSF/plasma discordance and factors associated with this occurrence, and b) the prevalence of HIV-1 RNA detection in CSF in those with HIV-1 RNA persistence in plasma. A sensitive assay detected HIV-1 RNA below 50 copies/ml in a subgroup and a cytometric bead array determined CSF biomarkers. A matrix of clinical features and CSF/plasma biomarkers was related to cognitive decline in subjects from the CHARTER study. Drug concentrations in CSF and plasma were measured by mass spectrometry assays and related to host genetic factors in subjects in the PARTITION study and a Vietnamese cohort with tuberculous meningitis. Results. CSF/plasma HIV discordance occurred in 13% of this cohort and was associated with nadir, but not current, CD4 cell count. CSF/plasma discordance occurred in 7 of 40 (18%) of subjects with ongoing viral detection in plasma vs. 0 of 39 of those without. Residual HIV-1 RNA detection below 50 copies/ml was also associated with CSF HIV-1 RNA detection. Resistance associated HIV mutations were detected in CSF of subjects with CSF/plasma discordance. CSF/plasma discordance above 0.5log10 was associated with raised profiles of inflammatory CSF proteomic biomarkers compared to those without discordance. In the CHARTER cohort, cognitive decline over 18 months was associated with lower concentrations of CSF TNFa and plasma IGF1/2. CSF concentrations of efavirenz were associated with the CYP2B6 c.516G>T single nucleotide polymorphism. Efavirenz metabolites were mainly glucuronidated in CSF, were present at neurotoxic levels, and were related to degree of blood brain barrier permeability. Host genetic factors were did not relate to CSF DRV concentrations. Conclusions. CSF/plasma discordance is a frequent occurrence, likely related to processes established during advanced immunosuppression not fully reversed by ART. It is associated with CSF HIV resistance and raised CSF biomarkers, even at levels 0.5-1log10 which have been considered non-significant in some studies. Potentially neurotoxic CSF concentrations of efavirenz relate to host genetic factors.
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Bingol, Cagin Gorkem. "Deformation Effects Of Straight Segment Of Flsc To Nearby Plates Due To Varying Backspace Distance." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/4/12605355/index.pdf.
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The objective of this study is to investigate the detrimental effects of a flexible linear
shaped charge (FLSC) to variable thickness back and constant thickness front plates due to
varying backspace distance. A FLSC is used to cut both metallic and non-metallic material,
quickly and efficiently. It is flexible and may be formed to produce cuts of many
configurations, thereby making it particularly useful where more conventional cutting
techniques are difficult to employ. While performing its function, the FLSC gives some
damage to the back due to the high transient pressure and fragmentation effects. In order to
decrease this damage, a steel plate is placed behind the FLSC.
In this work, a numerical analysis is carried out by using Autodyn Hydrocode for the
investigation of the extent of the plastic deformation of the back as well as front plates for
varying backspace distance of the steel plate having different thicknesses. The numerical results are then compared with the experimental findings. The flexibility property of the
FLSC is not used in this study. Only the straight segment of FLSC is used.
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Engeln, Jutta [Verfasser]. "Einfluss unterschiedlicher Adhäsiv-Komposit-Kombinationen auf die Zugfestigkeit des Schmelzverbundes selbstätzender Adhäsive und ihre Korrelation mit dem Penetrations- und Frakturverhalten in vitro / Jutta Engeln." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2010. http://d-nb.info/1023965232/34.
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Richter, Susan. "Neue zellpenetrierende Phosphopeptide für die molekulare Bildgebung." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-68594.
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Im Kontext komplexer zellulärer Prozesse stellen Phosphopeptide essentielle bioaktive Verbindungen dar, die mit Phosphorylierungs- und Dephosphorylierungsreaktionen eng verbunden sind. Diese Prozesse sind in die Regulation nahezu jeder zellulären Funktion involviert und spielen damit ebenso im Falle von Erkrankungen eine tragende Rolle. Synthetische Phosphopeptide könnten in Form molekularer Sonden zur Charakterisierung dieser physiologisch fundamentalen Prozesse beitragen. Die radiopharmazeutische Forschung brachte in den letzten zwei Jahrzehnten zahlreiche radiomarkierte Peptide für das Peptidrezeportargeting im Rahmen der Tumordiagnose und -therapie hervor. Unter diesen regulatorischen Peptiden mit vorwiegend neuroendokrinem Ursprung sind bisher keine radiomarkierten Phosphopeptide für die Anwendung in der molekularen Bildgebung bekannt.
Das Anliegen dieser Arbeit ist es, grundlegende Erkenntnisse zur Synthese und Markierung von Phosphopeptiden zu erlangen. Neben der Etablierung der Radiomarkierung von Phosphopeptiden mit dem kurzlebigen Positronenstrahler Fluor-18 und deren radiopharmakologischen Charakterisierung steht auch die Fluoreszenzmarkierung mit dem Fluorophor 5(6)-Carboxyfluorescein (CF) im Fokus. Phosphopeptidliganden der kürzlich identifizierten Polo-Box-Domäne (PBD) als Phosphopeptid-bindende Proteindomäne der Zellzykluskinase Plk1, die ebenso ein interessantes onkologisches Target darstellt, wurden für diese Arbeit als Model ausgewählt. Es stand ein Repertoire verschiedenster Methoden zur Verfügung, welche molekulare Bildgebung mittels Kleintier-PET, wie auch optische Bildgebung und die Radiomarkierung mittels klassischer und Mikrofluidik-Technik beinhalten.
Im ersten Abschnitt der Promotion wurden kürzlich vorgestellte Plk1-PBD-gerichtete Phosphopeptide mit einer Ser-pThr-Kernsequenz ausgewählt und deren Darstellung mit der Fmoc-gestützten orthogonalen Festphasenpeptidsynthese (SPPS) vollzogen. Dabei erfolgt die Umsetzung nach dem Prinzip des Synthon-basierten Ansatzes, der den Einsatz des monobenzylierten Phosphothreonin-Bausteines involviert. Das Uronium-basierte Kupplungs- und Aktivierungsreagenz HBTU/HOBt/DIPEA, sowie das Abspaltreagenz TFA/Wasser/Thioanisol/EDT als eine modifizierte Variante des Reagenz K garantiert die zuverlässige Synthese von Phosphopeptiden unter Erhalt der Phosphatfunktion. Zur Charakterisierung der Peptide wurden HPLC und Massenspektrometrie als geeignete Methoden herangezogen.
An die erfolgreiche Darstellung von Phosphopeptiden schloss sich im Weiteren die Ausarbeitung einer zuverlässigen Radiomarkierungsstrategie mit dem kurzlebigen Positronenstrahler Fluor-18 an. Das bifunktionelle, aminogruppenselektive Agenz
N-Succinimidyl-4-[18F]fluorbenzoat ([18F]SFB) ist für eine indirekte und milde Markierung von Peptiden geeignet. Durch Optimierung der N-terminalen 18F-Fluorbenzoylierung des Phosphopeptides MQSpTPL 2 hinsichtlich der Verwendung eines 0,05 M Na2HPO4-Puffers (pH 9) als Reaktionsmedium bei geringer Peptidmenge (0,5 mg), sowie 40°C Reaktionstemperatur und 30 min Reaktionszeit kann das 18F-markierte Phosphopeptid [18F]FBz-MQSpTPL [18F]4 in guten radiochemischen Ausbeuten von 25-28%, mit entsprechender radiochemischer Reinheit >95% mittels HPLC-Reinigung und guter spezifischer Aktivität (20-40 GBq/µmol) hergestellt werden.
Der Einsatz von Peptiden ist für die molekulare Bildgebung besonders attraktiv, jedoch oftmals durch ihre Instabilität in vivo, ausgelöst durch ubiquitär vorhandene endogene Peptidasen, limitiert. Beispielsweise besitzt ein N-terminal 18F-fluorbenzoyliertes Neurotensin(8-13) eine biologische Halbwertszeit von weniger als 5 min in vivo. Mit dem neuartigen 18F-markierten Phosphopeptid [18F]FBz-MQSpTPL [18F]4 wurde ein Peptid geschaffen, das in vitro und besonders in vivo außerordentlich hohe Stabilität von > 50% nach 60 min aufweist und damit wegweisende Eigenschaften für die Entwicklung neuer stabiler Radiopeptide für die molekulare Bildgebung aufzeigt.
Da Phosphopeptiden aufgrund ihrer negativgeladenen Phosphatfunktionalität ein intrazellulärer Zugang verwehrt bleibt, wie auch in dieser Arbeit an den Tumorzelllinien HT-29 und FaDu nachgewiesen wurde, steht die Realisierung einer verbesserten intrazellulären Internalisierung von Phosphopeptiden im Blickfeld des zweiten Teils der Promotion. Der Versuch einer gezielten Zellaufnahme über rezeptorinternalisierende Peptide wurde mit dem Neuropeptidhormon Neurotensin(8-13) (NT(8-13)), welches über einen G-Protein-gekoppelten Mechanismus in die Zelle gelangt, beschritten. Jedoch zeigte ein Triazol-verbrücktes Konjugat 8 aus NT(8-13) als molekularer Transporter und dem Phosphopeptid MQSpTPL 2, welches auf Basis der Azid-Alkin-Click-Chemie synthetisiert wurde, anhand seiner niedrigen Bindungsaffinität (IC50 = 8,33 µM) kein Potential zu einer erfolgreichen Zellinternalisierung des Phosphopeptides.
Vermittler eines rezeptorunabhängigen molekularen Zelltransportes stellen zellpenetrierende Peptide (CPP) dar. Versuche mit den derzeit kürzesten CPPs, den zellpenetrierenden Pentapeptiden (CPP5) oder auch Bax-Inhibitoren genannt, waren nicht erfolgreich. Zwei weitere, in dieser Arbeit verwendete, potente CPPs sind sC18, abgeleitet aus dem antimikrobiellen Peptid Cathelicidin, sowie hCT(18-32)-k7, einem verzweigten Calcitonin-Derivat. Mit den Phosphopeptid-CPP-konjugierten Verbindungen MQSpTPL-sC18 2-CPP1 und MQSpTPL-hCT(18-32)-k7 2-CPP2 wurden nicht-toxische Konstrukte geschaffen, die eine definierte Aufnahme in HeLa, MCF-7 und HT-29 Zellen aufweisen, wie nach Markierung mit dem Fluoreszenzfarbstoff 5(6)-Carboxfluorescein (CF) mittels optischer Bildgebung nachgewiesen werden konnte.
Die Integration und Anwendung der Mikrofluidik-Technik im Rahmen der Darstellung der N-terminal 18F-fluorbenzoylierten Phosphopeptid-CPP-Konjugate [18F]FBz-MQSpTPL-sC18 [18F]2-CPP3 und [18F]FBz-MQSpTPL-hCT(18-32)-k7 [18F]2-CPP4 weist im Vergleich zur konventionellen Radiomarkierung entscheidende Vorteile auf. In Anwesenheit der für die [18F]SFB-Markierung reaktiven ε-NH2-Gruppen in den CPP-Fragmenten zeichnet sich im Rahmen der mikrofluiden Markierung entscheidende Selektivität für den N-Terminus der Peptide ab. Die radiochemischen Markierungsausbeuten betragen 21% für [18F]2-CPP3 und 26% für [18F]2-CPP4, im Vergleich zu 2-4% für [18F]2-CPP3 und [18F]2-CPP4 bei klassischer Markierung. In Zellaufnahmestudien wurde ebenfalls eine Internalisierung der 18F-markierten Konjugate in FaDu, HT-29 und MCF-7 Zellen bestätigt, die in allen drei Zelllinien vergleichbar ist und um 40% ID/mg Protein liegt. Wie auch das 18F-markierte Hexaphosphopeptid selbst in Wistar-Unilever-Ratten, zeigten die 18F-markierten Phosphopeptid-CPP-Konjugate in Kleintier-PET-Untersuchungen in Balb/C-Mäusen (Normaltiere) die für ein radiomarkiertes Peptid typische Bioverteilung. Hierbei ist eine renale Exkretion eingeschlossen.
Im Rahmen dieser Arbeit ist es gelungen, erstmals 18F-markierte Phosphopeptide mit zellpenetrierenden Eigenschaften für die molekulare Bildgebung zu entwickeln. Diese neuen zellpenetrierenden Phosphopeptide stehen für die Untersuchung intrazellulärer Prozesse, die auf Phosphorylierungs-/Dephosphorylierungsprozessen basieren, zur Verfügung.
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Gonzalez-Pena, Omar Israel. "Mass Transport Enhancement in Copper Electrodeposition due to Gas Co-Evolution." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1439826379.
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Chudoba, Rostislav, Inga Focke, Bong-Gu Kang, Vaclav Sadilek, Wilhelm Benning, and Wolfgang Brameshuber. "Abbildung der Verbundstruktur aus REM-Aufnahmen im geometrischen 3D Modell als Basis für die Modellierung des TRC-Verbundverhaltens auf der Mikroebene." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-77807.
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Zur Charakterisierung der Mikrostruktur wurde die Geometrie des Verbundes aus REM-Aufnahmen ausgewertet, sowie die Verbundwirkung einzelner Filamente aus Filament-Pull-Out-Versuchen abgeleitet. Die gewonnenen Parameter bilden die Grundlage für die Modellierung von Garnauszugs- und Rissüberbrückungsmodellen. Unabhängig davon wurde ein Filament-Matrix-Verbund-Gesetz simuliert. Die Übereinstimmungen zwischen der Simulation und der experimentellen Untersuchung des Ausziehverhaltens werden in dem Artikel diskutiert<br>The microstructure is characterized by analysing the bond geometrically and experimentally. The data to evaluate these two ways are from SEMimages and filament-pull-out-tests. Based on these data yarn-pull-out-models and crack-bridging-models are calculated. In addition a filament-matrix-bond-law is simulated independently. The correlation between the simulation and the experimental analysis of the pull-out behaviour is discussed in this paper
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Barreau, Kristell. "Le peptide NFL-TBS, 40-63 dérivés des neurofilaments : Agents thérapeutique prometteur pour cibler et manipuler les cellules souches neurales et les cellules de glioblastomes Review of Clinical Trials Using Neural Stem Cells The Neurofilament‐Derived Peptide NFL‐TBS.40‐63 Targets Neural Stem Cells and Affects Their Properties The carbocyanine dye DiD labels in vitro and in vivo neural stem cells of the subventricular zone as well as myelinated structures following in vivo injection in the lateral ventricle." Thesis, Angers, 2017. http://www.theses.fr/2017ANGE0087.
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Les travaux menés au laboratoire ont mis en évidence des sites de liaison de la tubuline (TBS pour Tubulin Binding Site) sur les filaments intermédiaires, tels que les neurofilaments (NFs), qui sont spécifiquement exprimés par les neurones. Le peptide NFL-TBS.40-63 qui correspond à la séquence en acide aminés du TBS situé sur la sous unité légère des NFs, a montré des propriétés anti-glioblastomes in vitro et in vivo, sans effet sur les cellules saines environnantes (neurones et astrocytes). De plus, Il est aussi capable d’induire la différenciation et la maturation des précurseurs d’oligodendrocytes sans affecter la viabilité de ces cellules.Les travaux menés au cours de cette thèse ont permis de valoriser le peptide NFL-TBS.40-63 comme agent thérapeutique possible pour la médecine régénérative. En effet, nous avons montré que le peptide est capable de pénétrer dans les cellules souches neurales (CSNs) in vitro de manière passive et in vivo, et n’est pas toxique pour les cellules. Après plusieurs jours en présence du peptide, les propriétés dites « souches » des cellules, telle que la capacité à proliférer et à s’auto-renouveler diminuent, et les cellules se différencient en cellules plus matures. Ces résultats indiquent que le peptide pourrait être un agent thérapeutique intéressant pour cibler les CSNs endogènes du cerveau dans le cas de maladies neurodégénératives afin de stimuler la différenciation de ces cellules<br>The Iaboratory discovered the presence of tubulin binding sites (TBS) on intermediate filaments, like on the neurofilaments (NF) that are specifically expressed by neurons. The NFL-TBS.40-63 peptide, which corresponds to the sequence of TBS on the light subunit of NF, has showed an anti-glioblastoma property in vitro and in vivo, without effect on surrounding healthy cells (neurons and astrocytes). Moreover, it induces the differentiation and maturation of oligodendrocyte precursors without impacting the viability of these cells. Our studies during the PhD, allowed us to exploit the NFL-TBS.40-63 peptide as a possible therapeutic agent for regenerative medicine. Indeed, we showed that the peptide penetrates passively in neural stem cells (NSCs) in vitro and in vivo, and it is not toxic for cells. After several days with the peptide, the "stem" cell properties of cells, including the capacity to proliferate and self-renew, diminish and the cells differentiate into more mature cells.These data indicate that the NFL-TBS.40-63 peptide could be a promising therapeutic agent to target endogenous brain NSCs in neurodegenerative disorders to stimulate the differentiation of these cells
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Hsu, Hui-Ling, and 徐慧玲. "The study of polymeric micelles'' stability and transdermal penetration by fluorescence dye." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/77ras8.
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碩士<br>臺北醫學大學<br>藥學系(碩博士班)<br>102<br>The study used two fluorescence dyes’ Fluorescence resonance energy transfer (FRET) to evaluate the stability of polymeric micelles by timing, environment, and mechanical shake.Moreover, we also use FRET to evaluate pros and cons of different polymers’ energy transfer. In vitro, we formulated polymeric micelles and two fluorescence dyes and observed the transdermal permeation by Franz Diffusion Cell System.
The results found that polymeric micelles and two fluorescence dyes’ ratio can sustain stable during 0～8 hours. Polymeric micelles and two fluorescence dyes’ ratio we affected under concentration of different dilutions, and the ratio could maintain stable mechanical under shaking. However, the different polymeric micelles’ FRET was different under different concentration fluorescence dyes.During 0～24 hours of Franz Diffusion Cell System’s experiment, it were found that two fluorescence dyes’ could transdermal penetration.
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Wilken-Engel, Kathrin. "Penetration von Pollenallergenen in die Haut /." 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=013149213&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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"Effect of Reduced System Inertia Due to Increased Renewable Resource Penetration on Power System Stability." Master's thesis, 2012. http://hdl.handle.net/2286/R.I.15090.
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abstract: This thesis concerns with the impact of renewable generation resources on the power system stability. The rapidly increasing integration of renewable energy sources into the grid can change the way power systems operate and respond to system disturbances. This is because the available inertia from synchronous machines, which helps in damping system oscillations, gets reduced as an increase in renewables like wind and solar photovoltaics is accompanied by a decrease in conventional generators. This aspect of high penetration of renewables has the potential to affect the rotor angle stability and small signal stability of power systems. The system with increased renewables is mathematically modeled to rep-resent wind and solar resources. Transient and small signal stability studies are performed for various operating cases. The main conclusion drawn from the different studies is that increased renewable penetration causes a few instability problems, most of which are either localized and do not adversely affect the over-all system stability. It is also found that the critical inter-area modes of oscillations are sufficiently damped.<br>Dissertation/Thesis<br>M.S. Electrical Engineering 2012
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Hölsken, Olaf [Verfasser]. "Zur Vehikelabhängigkeit der Penetration von α-Tocopherolacetat [Alpha-Tocopherolacetat] in die menschliche Haut / von Olaf Hölsken". 2005. http://d-nb.info/979551099/34.
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Mangelsdorf, Susanne [Verfasser]. "Vergleichende Untersuchung hautphysiologischer Parameter mit Einfluss auf die perkutane Penetration bei verschiedenen Spezies / vorgelegt von Susanne Mangelsdorf." 2007. http://d-nb.info/984936459/34.
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Flor, Eduardo Rafael de Lima. "Desinfeção aplicada aos cones de guta-percha." Master's thesis, 2015. http://hdl.handle.net/10284/5448.
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Introdução: Ao longo do tempo o Tratamento Endodôntico Não Cirúrgico tem sido
das áreas da Medicina Dentária que mais tem evoluído. Todos os passos do
tratamento têm sido revistos de forma a aumentar a taxa de sucesso. O controlo
microbiológico é crucial para que o tratamento seja um sucesso a curto, médio e longo
prazo. A assepsia deve ser mantida em todas as fases deste tratamento para que este
seja um sucesso.
Objetivo: Ao longo do meu percurso académico pude concluir que a fase da
descontaminação dos cones, aquando a obturação (fase final do Tratamento
Endodôntico Não Cirúrgico) era desvalorizada, o que me levou a efetuar uma revisão
bibliográfica de modo a poder melhorar os meus conhecimentos e técnica.
Material e Métodos: Para a elaboração deste trabalho foi realizada uma pesquisa
bibliográfica recorrendo aos seguintes motores de busca: B-on, PubMed, Scielo e
ScienceDirect, com as seguintes palavras-chave: “decontamination in endodontics”;”
disinfection in endodontics”; “root canal irrigants”; “endodontics microbiology”;
“Candida albicans“; “Enterococcus faecalis”; “sodium hypochlorite ”; “alcohol”;
“contamination during Obturation”; “clorohexidine”; “filling materials endodontics”;
“termoplastic gutta-percha”; “obturation material”; “Mineral Trioxide Aggregate”;
“resilon”; “resin cement”; “resin material for root canal obturation”; “resin sealer”;
“root canal”; “root canal sealing”; “root canal filling materials”; “condensation in
endodontics”; “lateral condensation”; “gutta-percha”; “microlekeage”; “system B”;
“fluid filtration model”;“dye penetration”. Como critério de inclusão estabeleceu-se
que os artigos deveriam ser em Português, Inglês ou Espanhol e publicados entre
1995 e 2015.
Dos resultados apresentados foram utilizados 110 artigos, pesquisados entre Maio de
2015 e 20 de Outubro de 2015. Foram ainda consultados livros de referência nestes
mesmos locais. Conclusão: a presença de bactérias e os seus subprodutos no sistema tridimensional
de canais está diretamente implicado com o insucesso do Tratamento Endodôntico. A
descontaminação dos cones de guta-percha, é, portanto, um processo importante no
Tratamento Endodôntico pois impede que os cones sejam colocados nos canais
radiculares, estando contaminados por microorganismos que inviabilizam o
tratamento efetuado. A submersão dos cones durante um minuto em clorohexidina a
2% ou hipoclorito a 5,25% está indicado e comprovado como um processo eficiente
de desinfeção dos cones.<br>Introduction: Throughout time non surgical endodontic treatment has been one of the
most developed areas in dentistry. All the procedures have been reviewed to increase
the success rate. Microbiological control is crucial so that treatment can be successul
in a short, medium and long-term period, It is important to have a good
microbiological control. Sepsis must be kept at all stages of the treatment in order to
achieve success.
Objective: During my academic years, I realised that the decontamination of the cone
during the root filling (final phase of Endodontic Treatment Non Surgical) was
underrated. So, I felt compelled to read more about this matter in order to improve my
knowledge and technique on this issue.
Materials and Methods: Literature search was made through B-on, PubMed, Scielo e
ScienceDirect, Key-words: “decontamination in endodontics”;” disinfection in
endodontics”; “root canal irrigants”; “endodontics microbiology”; “Candida
albicans“; “Enterococcus faecalis”; “sodium hypochlorite ”; “alcohol”;
“contamination during Obturation”; “clorohexidine”; “filling materials endodontics”;
“termoplastic gutta-percha”; “obturation material”; “Mineral Trioxide Aggregate”;
“resilon”; “resin cement”; “resin material for root canal obturation”; “resin sealer”;
“root canal”; “root canal sealing”; “root canal filling materials”; “condensation in
endodontics”; “lateral condensation”; “gutta-percha”; “microlekeage”; “system B”;
“fluid filtration model”;“dye penetration”. The inclusion criteria established the use of
articles in Portuguese, English and Spanish and those that were published
between1995 And 2015.
In this paper, I used 110 articles researched between May 2015 and 20 October 2015,
as well as books between the same period of time.
Conclusion: The presence of bacteria and their byproducts in a three-dimensional
system of channels is directly involved with the failure of Endodontic treatment. The
decontamination of gutta-percha is of the greatest importance to the endodontic
treatment beacuse it prevents that the cones placed into the root canal are contaminated by microorganisms and so cause the treatment not to be effective..
Therefore submerging the cones for one minute at 2% chlorhexidine or hypochlorite
5.25% is an effective process of disinfection of the cones.
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Rettkowski, Udo [Verfasser]. "Einfluss von ausgewählten Cyclodextrinen auf die corneale Metabolisierung und auf das Penetrations- und Permeationsverhalten von Dipivefrin / von Udo Rettkowski." 2003. http://d-nb.info/968860877/34.
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Siefert, Burkhard. "Einfluß von Cyclodextrin auf die Löslichkeit und okulare Verfügbarkeit von Pilocarpin-HC1 bzw. Thalidomid : Penetrations- und Permeationsstudien an isolierter Cornea /." 1998. http://www.gbv.de/dms/bs/toc/254829090.pdf.
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Tsai, Yu-Hao, and 蔡宇浩. "A Simulation Study on Application of Ground-penetrating Radar to the Identification of Shallow Cavity in Coastal Dyke." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/50726702555726794414.
Full textAbstract:
碩士<br>逢甲大學<br>土木工程學系<br>101<br>The coastal dikes are the first protective barrier for inland safety. Because of the climate change and the increasing of flood. The cavities of coast dikes are often found be located beneath the bottom of the concrete plate. Due to the existence of the surface cracks or construction joints, sea waters can flow into the body of the dike. This will result in soil consolidation, settlement, and the formation of some cavities in the soil.
The thesis used the finite difference program GprMax2D to study the effects of cavity beneath a concrete plate. An average area difference for dyke with and without cavities was proposed in this study as a quantitative index for cavity existence. In addition, the geometric shape of cavity, the depth of the cavity under the concrete plate, the thickness of the concrete plate and the dielectric constants of concrete plate and soil.
The research results showed that the area difference will generally increase its value as the increase of the cavity size, but it will decrease when cavity size increases to some certain value. Too flat or too narrow and long cavities’ signals was hard to identify because of the repeatedly reflected. Also, the area difference of the cavity width changes is larger than the cavity height changes.
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Chung, Yu, and 鍾渝. "Analytical model for non-Darcian flow toward a partially penetrating well due to constant-rate pumping in a fractured confined aquifer." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/pk3h2q.
Full textAbstract:
碩士<br>國立交通大學<br>環境工程系所<br>106<br>This study presents a mathematical model for describing the drawdown distribution to analyze non-Darcian flow for constant-rate pumping at a partially penetrating well in a fractured confined aquifer of infinite extent. The model is developed based on the double-porosity concept combined with a linearized non-Darcian flow approach using Izbash’s law. The solution of the model in Laplace domain is derived via the methods of finite Fourier cosine transform and Laplace transform. The time-domain results are numerically evaluated by the Crump scheme. Both large-time and small-time solutions for transient flow are derived based on the convolution theorem and the Bromwich integral and the steady-state solution is also developed. The existing solutions for non-Darcian flow are shown to be special cases of the present solution. The solution is then compared with the finite difference solution to verify its correctness. Also, the comparison between the present solution and exiting solution for Darcian flow reveals that the fluid exchange from the matrix blocks to the fractures occurring in the intermediate time. The effects of exchange coefficient and non-Darcian factor on the temporal drawdown are examined. Moreover, the sensitivity analysis is performed to investigate the drawdown behavior in response to the change in each of the hydraulic parameters. Finally, the present solution is coupled with the Levenberg-Marquardt algorithm to analyze two sets of field measured data for estimating the hydraulic parameters. This present solution is a useful tool in predicting the non-Darcian flow in fractured confined aquifers and determining the aquifer hydraulic parameters for double-porosity media.
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Ningtyas, Alviani Hesthi Permata, and Alviani Hesthi Permata Ningtyas. "A new experimental design to measure the penetrative entrainment flow rate due to a transition or turbulent fountain at a density interface." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/fxahzy.
Full textAbstract:
碩士<br>國立臺灣科技大學<br>機械工程系<br>104<br>Penetrative entrainment by a turbulent fountain has many practical applications
in nature. The examples include the cooling system in the commercial building,
recirculating a water reservoir and the process of improving the water quality.
This research studied the penetrative entrainment flow rate quantitatively. A
new experimental design was developed to estimate the penetrative entrainment
volume flow rate by a turbulent fountain.
Simulation experiments used the salt bath technique. Two sources, a salt solution source and a fresh water source, were placed in a plexiglass tank. Two
sources were located at different heights, the fresh water source at the top and the salt solution source at 2 cm above the floor of the tank. There were 9 experimental runs conducted in this research, and the flow from the fresh water source hit the floor boundary in 3 runs of them. Two data acquisition methods included the measurements of solution density and the recording of flow images.
Experiments started from the 2 layers initially with the fresh water as the
upper layer and the salt solution as the lower layer. After the experiment began,
the density in the upper dilute layer increased with the time until the steady state
and the density in the lower dense layer remained the same in the transient state
except for the cases in which the fountain flow hit the floor boundary. When the
fresh water flow hit the floor boundary, the density of the lower dense layer was less than that of the salt solution and the interface was unclear. For the experimental cases in which the fountain flow does not reach the floor, this new experimental set-up gives three independent equations to estimate the penetrative entrainment flow rate by a fountain flow. Using the numerical turbulent fountain flow model gives the Richardson number at the density interface between 0.029 and 1.816 and the entrainment rate in the range between 0.13 and 2.21, when the initial fountain momentum is 4/3 Q2f/A , and the Richardson number at the density interface between 0.044 and 14.389 and the entrainment rate in the range between 0.12 and 2.08, when the initial fountain momentum is Q2 /A .
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Lo, Chi-Hao, and 羅濟灝. "An experimental arrangement on measuring the penetrative entrainment flow rate due to a turbulent fountain at a density interface in the steady state." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9xdyj6.
Full textAbstract:
碩士<br>國立臺灣科技大學<br>機械工程系<br>105<br>This research uses an experimental arrangement to measure the penetrative entrainment flow rate due to a turbulent fountain at a density interface in the steady state. The salt-bath technique is employed to conduct the experiments in an acrylic model. Experiments start with two layers of fluids initially, i.e. fresh water as the top and salt water as the bottom. Two sources, a fresh water source and a salt water source, are located at different heights in the acrylic model. A fresh water source is placed at the top of the acrylic model, and there is a stainless steel mesh placed at the outlet of the fresh water nozzle to make the outflow become turbulent. A salt water source is placed at 2 cm above the bottom of the acrylic model by using an acrylic pipe to supply salt water to the bottom layer. Dye attenuation technique is used to analyze the light intensity data derived from the recorded images of experiments. According to the density of salt water and the volume flow rate of fresh water, there are eight experiments in this research. The experimental results show that the interface height is highly related to the density of salt water and the volume flow rate of fresh water in the steady state. For the experiments having the same density of salt water, the distance between the density interface and the fresh water source increases with the increasing volume flow rate of fresh water. For the experiments having the same flow rate of fresh water, when the density of salt water increases, the distance between the density interface and the fresh water sources decreases. The theoretical model gives three equations to estimate the penetrative entrainment flow rate in the steady state. The theoretical turbulent fountain model gives the turbulent fountain radius, the vertical velocity and the volume flow rate at the density interface to estimate the penetrative entrainment rate, the Richardson number, and the densimetric Froude number. The research results show the Richardson number at the density interface between 0.030 and 4.261, and the penetrative entrainment rate in the range of 0.13 to 2.32.
Keywords: Density interface, turbulent fountain, penetrative entrainment, steady-state experimental arrangement.
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Richter, Susan. "Neue zellpenetrierende Phosphopeptide für die molekulare Bildgebung." Doctoral thesis, 2010. https://tud.qucosa.de/id/qucosa%3A25574.
Full textAbstract:
Im Kontext komplexer zellulärer Prozesse stellen Phosphopeptide essentielle bioaktive Verbindungen dar, die mit Phosphorylierungs- und Dephosphorylierungsreaktionen eng verbunden sind. Diese Prozesse sind in die Regulation nahezu jeder zellulären Funktion involviert und spielen damit ebenso im Falle von Erkrankungen eine tragende Rolle. Synthetische Phosphopeptide könnten in Form molekularer Sonden zur Charakterisierung dieser physiologisch fundamentalen Prozesse beitragen. Die radiopharmazeutische Forschung brachte in den letzten zwei Jahrzehnten zahlreiche radiomarkierte Peptide für das Peptidrezeportargeting im Rahmen der Tumordiagnose und -therapie hervor. Unter diesen regulatorischen Peptiden mit vorwiegend neuroendokrinem Ursprung sind bisher keine radiomarkierten Phosphopeptide für die Anwendung in der molekularen Bildgebung bekannt.
Das Anliegen dieser Arbeit ist es, grundlegende Erkenntnisse zur Synthese und Markierung von Phosphopeptiden zu erlangen. Neben der Etablierung der Radiomarkierung von Phosphopeptiden mit dem kurzlebigen Positronenstrahler Fluor-18 und deren radiopharmakologischen Charakterisierung steht auch die Fluoreszenzmarkierung mit dem Fluorophor 5(6)-Carboxyfluorescein (CF) im Fokus. Phosphopeptidliganden der kürzlich identifizierten Polo-Box-Domäne (PBD) als Phosphopeptid-bindende Proteindomäne der Zellzykluskinase Plk1, die ebenso ein interessantes onkologisches Target darstellt, wurden für diese Arbeit als Model ausgewählt. Es stand ein Repertoire verschiedenster Methoden zur Verfügung, welche molekulare Bildgebung mittels Kleintier-PET, wie auch optische Bildgebung und die Radiomarkierung mittels klassischer und Mikrofluidik-Technik beinhalten.
Im ersten Abschnitt der Promotion wurden kürzlich vorgestellte Plk1-PBD-gerichtete Phosphopeptide mit einer Ser-pThr-Kernsequenz ausgewählt und deren Darstellung mit der Fmoc-gestützten orthogonalen Festphasenpeptidsynthese (SPPS) vollzogen. Dabei erfolgt die Umsetzung nach dem Prinzip des Synthon-basierten Ansatzes, der den Einsatz des monobenzylierten Phosphothreonin-Bausteines involviert. Das Uronium-basierte Kupplungs- und Aktivierungsreagenz HBTU/HOBt/DIPEA, sowie das Abspaltreagenz TFA/Wasser/Thioanisol/EDT als eine modifizierte Variante des Reagenz K garantiert die zuverlässige Synthese von Phosphopeptiden unter Erhalt der Phosphatfunktion. Zur Charakterisierung der Peptide wurden HPLC und Massenspektrometrie als geeignete Methoden herangezogen.
An die erfolgreiche Darstellung von Phosphopeptiden schloss sich im Weiteren die Ausarbeitung einer zuverlässigen Radiomarkierungsstrategie mit dem kurzlebigen Positronenstrahler Fluor-18 an. Das bifunktionelle, aminogruppenselektive Agenz
N-Succinimidyl-4-[18F]fluorbenzoat ([18F]SFB) ist für eine indirekte und milde Markierung von Peptiden geeignet. Durch Optimierung der N-terminalen 18F-Fluorbenzoylierung des Phosphopeptides MQSpTPL 2 hinsichtlich der Verwendung eines 0,05 M Na2HPO4-Puffers (pH 9) als Reaktionsmedium bei geringer Peptidmenge (0,5 mg), sowie 40°C Reaktionstemperatur und 30 min Reaktionszeit kann das 18F-markierte Phosphopeptid [18F]FBz-MQSpTPL [18F]4 in guten radiochemischen Ausbeuten von 25-28%, mit entsprechender radiochemischer Reinheit >95% mittels HPLC-Reinigung und guter spezifischer Aktivität (20-40 GBq/µmol) hergestellt werden.
Der Einsatz von Peptiden ist für die molekulare Bildgebung besonders attraktiv, jedoch oftmals durch ihre Instabilität in vivo, ausgelöst durch ubiquitär vorhandene endogene Peptidasen, limitiert. Beispielsweise besitzt ein N-terminal 18F-fluorbenzoyliertes Neurotensin(8-13) eine biologische Halbwertszeit von weniger als 5 min in vivo. Mit dem neuartigen 18F-markierten Phosphopeptid [18F]FBz-MQSpTPL [18F]4 wurde ein Peptid geschaffen, das in vitro und besonders in vivo außerordentlich hohe Stabilität von > 50% nach 60 min aufweist und damit wegweisende Eigenschaften für die Entwicklung neuer stabiler Radiopeptide für die molekulare Bildgebung aufzeigt.
Da Phosphopeptiden aufgrund ihrer negativgeladenen Phosphatfunktionalität ein intrazellulärer Zugang verwehrt bleibt, wie auch in dieser Arbeit an den Tumorzelllinien HT-29 und FaDu nachgewiesen wurde, steht die Realisierung einer verbesserten intrazellulären Internalisierung von Phosphopeptiden im Blickfeld des zweiten Teils der Promotion. Der Versuch einer gezielten Zellaufnahme über rezeptorinternalisierende Peptide wurde mit dem Neuropeptidhormon Neurotensin(8-13) (NT(8-13)), welches über einen G-Protein-gekoppelten Mechanismus in die Zelle gelangt, beschritten. Jedoch zeigte ein Triazol-verbrücktes Konjugat 8 aus NT(8-13) als molekularer Transporter und dem Phosphopeptid MQSpTPL 2, welches auf Basis der Azid-Alkin-Click-Chemie synthetisiert wurde, anhand seiner niedrigen Bindungsaffinität (IC50 = 8,33 µM) kein Potential zu einer erfolgreichen Zellinternalisierung des Phosphopeptides.
Vermittler eines rezeptorunabhängigen molekularen Zelltransportes stellen zellpenetrierende Peptide (CPP) dar. Versuche mit den derzeit kürzesten CPPs, den zellpenetrierenden Pentapeptiden (CPP5) oder auch Bax-Inhibitoren genannt, waren nicht erfolgreich. Zwei weitere, in dieser Arbeit verwendete, potente CPPs sind sC18, abgeleitet aus dem antimikrobiellen Peptid Cathelicidin, sowie hCT(18-32)-k7, einem verzweigten Calcitonin-Derivat. Mit den Phosphopeptid-CPP-konjugierten Verbindungen MQSpTPL-sC18 2-CPP1 und MQSpTPL-hCT(18-32)-k7 2-CPP2 wurden nicht-toxische Konstrukte geschaffen, die eine definierte Aufnahme in HeLa, MCF-7 und HT-29 Zellen aufweisen, wie nach Markierung mit dem Fluoreszenzfarbstoff 5(6)-Carboxfluorescein (CF) mittels optischer Bildgebung nachgewiesen werden konnte.
Die Integration und Anwendung der Mikrofluidik-Technik im Rahmen der Darstellung der N-terminal 18F-fluorbenzoylierten Phosphopeptid-CPP-Konjugate [18F]FBz-MQSpTPL-sC18 [18F]2-CPP3 und [18F]FBz-MQSpTPL-hCT(18-32)-k7 [18F]2-CPP4 weist im Vergleich zur konventionellen Radiomarkierung entscheidende Vorteile auf. In Anwesenheit der für die [18F]SFB-Markierung reaktiven ε-NH2-Gruppen in den CPP-Fragmenten zeichnet sich im Rahmen der mikrofluiden Markierung entscheidende Selektivität für den N-Terminus der Peptide ab. Die radiochemischen Markierungsausbeuten betragen 21% für [18F]2-CPP3 und 26% für [18F]2-CPP4, im Vergleich zu 2-4% für [18F]2-CPP3 und [18F]2-CPP4 bei klassischer Markierung. In Zellaufnahmestudien wurde ebenfalls eine Internalisierung der 18F-markierten Konjugate in FaDu, HT-29 und MCF-7 Zellen bestätigt, die in allen drei Zelllinien vergleichbar ist und um 40% ID/mg Protein liegt. Wie auch das 18F-markierte Hexaphosphopeptid selbst in Wistar-Unilever-Ratten, zeigten die 18F-markierten Phosphopeptid-CPP-Konjugate in Kleintier-PET-Untersuchungen in Balb/C-Mäusen (Normaltiere) die für ein radiomarkiertes Peptid typische Bioverteilung. Hierbei ist eine renale Exkretion eingeschlossen.
Im Rahmen dieser Arbeit ist es gelungen, erstmals 18F-markierte Phosphopeptide mit zellpenetrierenden Eigenschaften für die molekulare Bildgebung zu entwickeln. Diese neuen zellpenetrierenden Phosphopeptide stehen für die Untersuchung intrazellulärer Prozesse, die auf Phosphorylierungs-/Dephosphorylierungsprozessen basieren, zur Verfügung.
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McCanna, David. "Development of Sensitive In Vitro Assays to Assess the Ocular Toxicity Potential of Chemicals and Ophthalmic Products." Thesis, 2009. http://hdl.handle.net/10012/4338.
Full textAbstract:
The utilization of in vitro tests with a tiered testing strategy for detection of mild ocular irritants can reduce the use of animals for testing, provide mechanistic data on toxic effects, and reduce the uncertainty associated with dose selection for clinical trials. The first section of this thesis describes how in vitro methods can be used to improve the prediction of the toxicity of chemicals and ophthalmic products. The proper utilization of in vitro methods can accurately predict toxic threshold levels and reduce animal use in product development. Sections two, three and four describe the development of new sensitive in vitro methods for predicting ocular toxicity. Maintaining the barrier function of the cornea is critical for the prevention of the penetration of infections microorganisms and irritating chemicals into the eye. Chapter 2 describes the development of a method for assessing the effects of chemicals on tight junctions using a human corneal epithelial and canine kidney epithelial cell line. In Chapter 3 a method that uses a primary organ culture for assessing single instillation and multiple instillation toxic effects is described. The ScanTox system was shown to be an ideal system to monitor the toxic effects over time as multiple readings can be taken of treated bovine lenses using the nondestructive method of assessing for the lens optical quality. Confirmations of toxic effects were made with the utilization of the viability dye alamarBlue. Chapter 4 describes the development of sensitive in vitro assays for detecting ocular toxicity by measuring the effects of chemicals on the mitochondrial integrity of bovine cornea, bovine lens epithelium and corneal epithelial cells, using fluorescent dyes.
The goal of this research was to develop an in vitro test battery that can be used to accurately predict the ocular toxicity of new chemicals and ophthalmic formulations. By comparing the toxicity seen in vivo animals and humans with the toxicity response in these new in vitro methods, it was demonstrated that these in vitro methods can be utilized in a tiered testing strategy in the development of new chemicals and ophthalmic formulations.