Dissertations / Theses: 'Adhesive Interactions'

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Ren, Dakai. "Moisture-Cure Polyurethane Wood Adhesives: Wood/Adhesive Interactions and Weather Durability." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/29866.

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This project addresses two main subjects of moisture-cure polyurethane (PUR) wood adhesives: wood/PUR interactions and structure-property behavior emphasizing on weather durability. For these purposes, one simplified model PUR (MPUR) and three more commercially significant PURs (CPURs) with different hard segment contents were prepared. Separately, an early side project involved the synthesis of a 13C and 15N double-labeled polymeric methylenebis(phenylisocyanate) (pMDI) resin; this was used for the solid-state NMR characterization of isocyanate cure chemistry in wood bondline. MPUR and a CPUR were employed to investigate whether wood/adhesive interactions influence PUR properties. Wood interactions significantly altered PUR hard/soft domain size distribution (atomic force microscopy, AFM), thermal transition temperatures (dynamic mechanical analyses, DMA), and urethane/urea hydrogen bonds (Fourier transform infrared spectroscopy, FTIR). The effects of hard segment content on properties of PUR prepolymers, and cured PURs (films and wood composites) were studied. Hard segment content largely influenced the PURs’ molecular weights, viscosity, penetration, thermal transitions, and hard segment hydrogen bonds, but only slightly altered the dry (unweathered) bondline toughness. Three accelerated weathering procedures were developed to evaluate CPUR bondline weather durability through mode-I fracture testing. Both hard segment content and weathering conditions were found to significantly influence the bondline weather durability. Among these weathering procedures, only one (VPSS) was able to effectively distinguish weather durability of PUR adhesives, and therefore it was selected for detailed structure-weather durability studies. PUR weather durability was found to correlate with its moisture sensitivity and hard segment softening temperature; both were provided by water-submersion DMA. Much attention was directed to the investigation of weather-induced PUR molecular changes. FTIR studies provided evidences of post-cure, hydrolytic degradation, and variation of urethane/urea hydrogen bonds. DMA presented weathering effects on PUR thermal properties. Special efforts have been made to correlate these analytical results with PUR weather durability. A 13C and 15N double-labeled pMDI resin was synthesized and used for solid-state NMR characterization of isocyanate cure chemistry in wood bondline, particularly to detect the evidence of urethane formation. Rotational echo double resonance (REDOR) NMR clearly revealed the formation of urethane linkages, but largely overestimated their content.
Ph. D.

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Cavenagh, James Durrell. "Adhesive interactions of leukaemic cells with endothelium." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244210.

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Di, Fino Alessio. "Comparative approach to barnacle adhesive-surface interactions." Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/2838.

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Barnacles are considered to be one of the major marine fouling organisms. Their settlement behaviour has been investigated using mainly Balanus amphitrite as a model organism. To better understand the mechanisms involved during the colonisation of surfaces by cypris larvae we have investigated another species, B. improvisus, which is reported to have different surface preferences compared to B. amphitrite. This study aims to unravel the effects of surface physicochemical cues, in particular surface free energy (SFE), surface charge and elastic modulus on the settlement of cyprids of both species. The use of well-defined surfaces under controlled conditions further facilitates comparison of the results with B. amphitrite. Furthermore, since this phase of presettlement behaviour is characterised by temporary adhesive (footprint) deposition, considered to be fundamental to surface exploration and surface discrimination by cyprids, some of the chemistries used for the settlement assays were used to investigate temporary adhesive-surface interactions. Cyprids were exposed to a series of model surfaces, namely self-assembled monolayers (SAMs) of alkanethiols with varying end-groups, homogenously applied to gold-coated polystyrene Petri dishes. The settlement response was significantly higher on negatively charged SAMs and lower on positively charged surfaces, while intermediate settlement occurred on neutral SAMs. Furthermore, no effects were observed when data were plotted against surface free energy after 48 hr of exposure. Temporary adhesive on SAMs was investigated using imaging ellipsometry and atomic force microscopy. Relatively thick footprints with low wetting were found on positively charged surfaces. Settlement of both species was also low on these surfaces. Footprints were thinner and spread more on hydrophobic surfaces. The adhesion force of temporary adhesive measured with functionalised AFM tips was higher on hydrophobic and negatively charged surfaces for both species. Furthermore, PDMS-based surfaces were prepared varying the elastic modulus, keeping constant other parameters, settlement behaviour and strength of adhesion of juveniles and adults were tested. We conclude that cyprid settlement behaviour of both species is influenced more by surface charge than SFE under controlled conditions. The temporary adhesives (footprints) of the two species had a stronger affinity for hydrophobic surfaces. Contrary ii to previous reports, therefore, the settlement preferences and adhesive secretion of these two species are similar. Elastic modulus influences settlement, juveniles and adults removal of both species, although B. improvisus is more sensitive if compared with B. amphitrite. This finding will be important for understanding the mechanism of surface selection by cyprids and for the development of future antifouling technologies.

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Liu, Haijing. "Wet adhesion properties of oilseed proteins stimulated by chemical and physical interactions and bonding." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35774.

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Doctor of Philosophy
Department of Grain Science and Industry
X. Susan Sun
The ecological and public health liabilities related with consuming petroleum resources have inspired the development of sustainable and environmental friendly materials. Plant protein, as a byproduct of oil extraction, has been identified as an economical biomaterial source and has previously demonstrated excellent potential for commercial use. Due to the intrinsic structure, protein-based materials are vulnerable to water and present relatively low wet mechanical properties. The purpose of this study focuses on increasing protein surface hydrophobicity through chemical modifications in order to improve wet mechanical strength. However, most of the water sensitive groups (WSG), such as amine, carboxyl, and hydroxyl groups, are also attributed to adhesion. Therefore, the goal of this research is to reduce water sensitive groups to an optimum level that the modified soy protein presents good wet adhesion and wet mechanical strength. In this research, we proposed two major approaches to reduce WSG: 1). By grafting hydrophobic chemicals onto the WSGs on protein surface; 2). By interacting hydrophobic chemicals with the WSGs. For grafting, undecylenic acid (UA), a castor oil derivative with 11-carbon chain with a carboxyl group at one end and naturally hydrophobic, was used. Carboxyl groups from UA reacted with amine groups from protein and converted amines into ester with hydrophobic chains grafting on protein surface. The successful grafting of UA onto soy protein isolate (SPI) was proved by both Infrared spectroscopy (IR) and ninhydrin test. Wood adhesive made from UA modified soy protein had reached the highest wet strength of 3.30 ± 0.24 MPa with fiber pulled out, which was 65% improvement than control soy protein. Grafting fatty acid chain was verified to improve soy protein water resistance. For interaction approach, soy oil with three fatty acid chains was used to modify soy protein. Soy oil was first modified into waterborne polyurethanes (WPU) to improve its compatibility and reactivity with aqueous protein. The main forces between WPU and protein were hydrogen bonding, hydrophobic interactions, and physical entanglement. Our results showed that WPU not only increased protein surface hydrophobicity with its fatty acid chains but also enhanced the three-dimensional network structure in WPU-SPI adhesives. WPU modification had increased wet adhesion strength up to 3.81 ± 0.34 MPa with fiber pulled out compared with 2.01 ± 0.46 MPa of SPI. Based on IR and thermal behavior changes observed by DSC, it was inferred that a new crosslinking network formed between WPU and SPI. To exam if the UA and WPU technologies developed using soy protein are suitable for other plant proteins, we selected camelina protein because camelina oil has superior functional properties for jet fuels and polymers. Like soy protein, camelina protein is also highly water sensitive. However, simply applied UA and WPU to camelina protein following the same methods used for soy proteins, we did not obtain the same good adhesion results compared to what we achieved with soy protein. After protein structure analysis, we realized that camelina protein is more compact in structure compared to soy protein that made it weak in both dry and wet adhesion strength. Therefore, for camelina protein, we unfolded its compact structure with Polymericamine epichlorohydrine (PAE) first to improve flexible chains with more adhesion groups for future reaction with UA or WPU. PAE with charged groups interacted camelina protein through electrostatic interaction and promoted protein unfolding to increase reactivity within protein subunits and between protein and wood cells. Therefore, the wet adhesion strength of camelina protein was improved from zero to 1.30 ± 0.23 MPa, which met the industrial standard for plywood adhesives in terms of adhesion strength. Then the wet adhesion strength of camelina protein was further improved after applying UA and WPU into the PAE modified camelina protein. In addition, we also found PAE unfolding significantly improved the dry adhesion strength of camelina protein from 2.39 ± 0.52 to 5.39 ± 0.50 MPa with 100% wood failure on two-layer wood test. Camelina meal which is even more economical than camelina protein was studied as wood adhesive. Through a combination of PAE and laccase modification method, the wet adhesion strength of camelina meal was improved as high as 1.04 ± 0.19MPa, which also met industrial standards for plywood adhesives. The results of this study had proven successful modification of oilseed protein to increase water resistance and wet mechanical strength. We have gained in-depth understanding of the relationship between protein structure and wet adhesion strength. The successful modification of plant proteins meeting the industrial needs for bio-adhesives will promote the development of eco-friendly and sustainable materials.

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Zhao, Boxin Pelton Robert H. "The interactions of pressure sensitive adhesive with paper surfaces." *McMaster only, 2004.

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Taubenberger, Anna Verena. "Quantifying adhesive interactions between cells and extracellular matrix by single-cell force spectroscopy." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-24758.

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Interactions of cells with their environment regulate important cellular functions and are required for the organization of cells into tissues and complex organisms. These interactions involve different types of adhesion receptors. Interactions with extracellular matrix (ECM) proteins are mainly mediated by the integrin family of adhesion molecules. Situations in which integrin-ECM interactions are deregulated cause diseases and play a crucial role in cancer cell invasion. Thus, the mechanisms underlying integrin-binding and regulation are of high interest, particularly at the molecular level. How can cell-ECM interactions be studied? While there are several methods to analyze cell adhesion, few provide quantitative data on adhesion forces. One group, single-cell force spectroscopy (SCFS), quantifies adhesion at the single-cell level and can therefore differentiate the adhesive properties of individual cells. One implementation of SCFS is based on atomic force microscopy (AFM); this technique has been employed in the presented work. Advantageously AFM-SCFS combines high temporal and spatial cell manipulation, the ability to measure a large range of adhesion forces and sufficiently high-force resolution to allow the study of single-molecule binding events in the context of a living cell. Since individual adhesion receptors can be analyzed within their physiological environment, AFM-SCFS is a powerful tool to study the mechanisms underlying integrin-regulation. The presented work is split into six chapters. Chapter one gives background information about cell-ECM interactions. In chapter two, different adhesion assays are compared and contrasted. The theoretical Bell-Evans model which is used to interpret integrin-mediated cell adhesion is discussed in chapter three. Thereafter, the three projects that form the core of the thesis are detailed in chapters four through six. In the first project (chapter 4), α2β1-integrin mediated cell adhesion to collagen type I, the most abundant structural protein in vertebrates, was quantified using CHO cells. Firstly, α2β1-collagen interactions were investigated at the single-molecule level. Dynamic force spectroscopy permitted calculation of bond specific parameters, such as the bond dissociation rate koff (1.3 ± 1.3 sec-1) and the barrier width xu (2.3 ± 0.3 Å). Next, α2β1-integrin mediated cell adhesion to collagen type I was monitored over contact times between 0 and 600 sec. Thereby the kinetics of α2β1-integrin mediated interactions was explored and insights into the underlying binding mechanisms were gained. In the second project (chapter five), effects of cryptic integrin binding sites within collagen type I exerted on pre-osteoblasts were investigated. Collagen type I matrices were thermally denatured which lead to exposure of cryptic RGD (Arg-Gly-Asp)-motifs. As a consequence pre-osteoblasts enhanced their adhesion to denatured collagen. Compared to native collagen type I, adhesion to denatured collagen was mediated by a different set of integrins, including αv- and α5β1-integrins. Cells grown on denatured collagen showed enhanced spreading and motility, which correlated with increased focal adhesion kinase phosphorylation levels. Moreover, osteogenic differentiation kinetics and differentiation potential were increased on denatured collagen. The findings of this project open new perspectives for optimization of tissue engineering substrates. In the third part (chapter six), the effect of the fusion protein BCR/ABL, a hallmark of chronic myeloid leukemia, on adhesion of myeloid progenitor cells was studied. Adhesion between BCR/ABL transformed progenitor cells to bone marrow derived stromal cells and to different ECM proteins was quantitatively compared to that of control cells. The tyrosine kinase activity of BCR/ABL enhanced cell adhesion, which was blocked by imatinib mesylate, a drug interfering with BCR/ABL activity. BCR/ABL-enhanced adhesion correlated with increased β1-integrin cell surface concentrations. Since adhesion of leukemic cells to the bone marrow compartment is critical for the development of drug resistance, the reported results may provide a basis for optimized target therapies. In the three described projects AFM-based SCFS was applied to investigate early steps of integrin-mediated adhesion at the molecular level. Taken together, the results demonstrate that AFM-SCFS is a versatile tool that permits monitoring of cell adhesion from single-molecule interactions to the formation of more complex adhesion sites at the force level
Interaktionen zwischen Zellen und ihrer Umgebung sind maßgeblich an der Regulierung zellulärer Funktionen beteiligt und daher notwendig für die Organisation von Zellen in Geweben und komplexen Organismen. Zellinteraktionen mit der extrazellulären Matrix (EZM) werden hauptsächlich durch Integrine vermittelt. Situationen, in denen Integrin- EZM Interaktionen verändert sind, können Krankheiten verursachen und spielen zudem eine wichtige Rolle bei der Invasion von Krebszellen. Daher besteht ein großes Interesse darin, die molekularen Mechanismen, die Integrin-EZM Interaktionen regulieren, besser zu verstehen. Wie können Zell-EZM Interaktionen untersucht werden? Obwohl es mehrere Methoden gibt, mit denen Zelladhäsion untersucht werden kann, sind die wenigsten dazu geeignet, Zelladhäsionskräfte zu quantifizieren. Einzelzellspektroskopie erfasst die Adhäsionskräfte einzelner Zellen quantitativ und ermöglicht dadurch eine differenzierte Betrachtung der Adhäsion individueller Zellen. Eine Variante der Einzelzellspektroskopie basiert auf der Rasterkraftmikroskopie (AFM); diese Technik wurde in der vorliegenden Arbeit verwendet. Ein Vorteil von AFM- Einzelzellspektroskopie besteht darin, dass Zellen mit hoher zeitlicher und räumlicher Präzision manipuliert werden können. Zelladhäsionskräfte können zudem über einen großen Kraftbereich hinweg untersucht werden. Dabei ermöglicht es die hohe Kraftauflösung, einzelne Integrin-Ligandenbindungen in lebenden Zellen zu untersuchen. Die vorliegende Arbeit gliedert sich in sechs Kapitel. Kapitel eins gibt Hintergrundinformationen über Zell-EZM Wechselwirkungen. In Kapitel zwei werden verschiedene Adhäsionsassays einander gegenüber gestellt. Das theoretische Bell-Evans Modell, mit dessen Hilfe die gewonnenen Daten interpretiert wurden, wird in Kapitel drei diskutiert. Im Anschluss werden drei Projekte, welche das Herzstück dieser Doktorarbeit bilden, in Kapiteln vier bis sechs näher ausgeführt. Im ersten Projekt (Kapitel vier) wurde die Adhäsion von α2β1-Integrin exprimierenden CHO Zellen zu Kollagen I, dem häufigsten strukturellen Protein in Wirbeltieren, quantitativ untersucht. Zunächst wurden α2β1-Kollagen-Interaktionen auf Einzelmolekülebene analysiert. Mithilfe der dynamischen Kraftspektroskopie wurden für diese Bindung Dissoziationsrate koff (1.3 ± 1.3 sec-1) und Potentialbarrierenbreite xu (2.3 ± 0.3 Å) bestimmt. Daraufhin wurde die α2β1-vermittelte Adhäsion über einen Zeitraum von zehn Minuten untersucht. Dadurch konnten Einblicke in die Kinetik von α2β1-integrin vermittelter Zelladhäsion sowie in die zugrunde liegenden Regulationsmechanismen gewonnen werden. Im zweiten Projekt (Kapitel fünf) wurde die Rolle von kryptischen Integrin-Bindungsstellen in Kollagen I untersucht. Die zuvor verwendeten Kollagenoberflächen wurden thermisch denaturiert, wodurch versteckte RGD (Arg-Gly-Asp)-Sequenzen freigelegt wurden. Die partielle Denaturierung hatte- verglichen mit nativem Kollagen I- eine erhöhte Adhäsion von Präosteoblasten (MC3T3-E1) zur Folge, was auf das Binden zusätzlicher Integrine zurückgeführt wurde. Im Unterschied zu nativem Kollagen wurde die Zelladhäsion zu denaturiertem Kollagen I u.a. durch αv- and α5β1-Integrine vermittelt. Präosteoblasten zeigten verstärktes Zellspreiten sowie höhere Motilität auf denaturiertem Kollagen I; zudem wurde ein erhöhtes Differenzierungpotential der Präosteoblasten festgestellt. Die in diesem Projekt erhaltenen Einblicke bilden eine hilfreiche Basis für die Entwicklung optimierter Oberflächen für diverse Zell- und Gewebekulturanwendungen. Im dritten Projekt (Kapitel sechs) wurde der Einfluss des Fusionproteins BCR/ABL, charakteristisch für chronische myeloische Leukämie, auf die Adhäsion von myeloischen Vorläuferzellen untersucht. Dazu wurde die Adhäsion von BCR/ABL transformierten Vorläuferzellen (32D Zellen) bzw. Kontrollzellen zu Stromazellen (M2-10B4) sowie verschiedenen EZM Proteinen untersucht. BCR/ABL erhöhte die Zelladhäsion der myeloischen Vorläuferzellen signifikant. Dieser Effekt wurde durch die Zugabe von Imatinib, welches die Tyrosinkinaseaktivität von BCR/ABL inhibiert, aufgehoben. Die BCR/ABL-verstärkte Zelladhäsion korrelierte mit erhöhten β1-Integrin-konzentrationen. Da die Adhäsion von Leukämiezellen im Knockenmark bekanntermaßen kritisch für die Entwicklung von Resistenzen gegenüber verschiedenen Wirkstoffen ist, könnten die Ergebnisse dieser Studie eine Grundlage für die Entwicklung optimierter Target-Therapien sein. In den drei beschriebenen Projekten wurde AFM Einzelzellspektroskopie verwendet, um Integrin- vermittelte Adhäsion auf molekularer Ebene zu untersuchen. Die Ergebnisse zeigen, dass AFM-Einzelzellspektroskopie ein vielseitiges Werkzeug darstellt, das überaus geeignet dazu ist, Zelladhäsion- ausgehend von Einzelmolekülinteraktionen bis hin zur Entstehung komplexerer Adhäsionsstellen- auf der Kraftebene zu verfolgen

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Choudhury, Devapriya. "Functional implications of macromolecular recognition : assembly of adhesive pili and enzyme substrate interactions /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-5820-X.pdf.

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Tucker, David. "Assessing the cellular and adhesive interactions in in vitro models of mantle cell lymphoma." Thesis, University of Plymouth, 2017. http://hdl.handle.net/10026.1/10235.

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Mantle cell lymphoma (MCL) is a rare lymphoproliferative disorder (LPD) that has very poor survival. Like other LPDs, the neoplastic cells of MCL have an intimate dependence upon accessory cells within haematopoietic tissues. Understanding and exploiting the tissue-relationships of the mantle cells may therefore lead to further new approaches to treatment. This study work has set out to construct an in vitro system to model relevant aspects of the tissue-dependent behaviour of the neoplastic mantle cells, seeking to establish the link between in vitro behaviour and clinical phenotype, and establishing the feasibility of this system to study the effects of different therapeutic interventions. The first experimental chapter employs relevant mouse and human stromal models to mirror the tissue environment of MCL in vivo. Testing relevant agents, the work establishes that the system can identify different behaviour between indolent and aggressive forms of MCL, and demonstrates a particular importance for CD40 ligand both in the proliferation and survival of the neoplastic mantle cells, but shows also how these effects are modulated by the soluble factors interleukin-4 (IL-4) and the toll-like receptor-9 ligand (TLR9-L). The second experimental chapter examines the adhesion molecules expressed on MCL cells. Considerable variation in the level of expression is observed between cases, but overall the cases express particularly high levels of the integrin receptors LFA-1 (detected by alpha chain CD11a) and VLA-4 (detected by alpha chain CD49d). Cases also showed a significant difference in overall adhesion and chemokine-receptor expression between cases that had either a nodal or leukaemic clinical pattern, although no single adhesion molecule was characteristic of clinical phenotype. The final experimental chapter looked at 3-D culture of MCL. Within tissues MCL grows in a 3-D rather than 2-D matrix and it is recognised that cells employ different forms of adhesion and migration within the different spatial environments. This chapter establishes the feasibility of growing cells in 3-D systems and looks at optimal conditions to preserve and examine the cellular characteristics of cells within a 3-D environment. Overall, this thesis demonstrates the feasibility and pathobiological relevance of ex vivo culture of MCL cells giving insights into the factors that drive MCL survival and proliferation and the correlation between in vitro behaviour and clinical phenotype. It is proposed that this work can be expanded to examine therapeutic interventions in the disorder.

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Masek, Lisa Christina. "The study of adhesive interactions between haemopoietic progenitor cells and bone marrow sinusoidal endothelial cells." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242854.

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Kryworuchko, Marko Andrii. "Regulation of CD44 and its adhesive interactions with the extracellular matrix component, hyaluronan, by cytokines in normal and transformed human B lymphocytes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0015/NQ46528.pdf.

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Kaur, Sukhmanjot. "EVALUATION OF MACROSCOPIC ADHESION AND INTERFACIAL INTERACTIONS OF MUSSEL-INSPIRED HYDROPHOBIC ADHESIVES." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1588611267867713.

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Koning, Paul Alan. "Investigation of acid/base interactions in adhesion." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53558.

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The fundamental study of Lewis acid/base interactions presented in this dissertation demonstrates the role of these interactions in adhesive phenomena. The model systems investigated were representative of real substrates and soft, viscoelastic adhesives where, in one case, favorable acid/base interactions were possible which were not possible in the other. Inverse gas chromatography (IGC) and Infrared spectroscopy (IR) techniques were used to analyze the model adhesive in terms of its acid/base nature. The results of both experiments indicated, through negative enthalpies of acid/base interaction with acidic solvents, that the model adhesive poly(2-ethyl hexyl methacrylate) (PEHMA) exhibits the properties of a Lewis base. The near quantitative agreement of the results from both experiments validate these methods of determining acid/base interactions in polymeric systems. Fitting the enthalpies for acid/base interaction to Drago’s and Gutmann’s models brought out the importance of the electrostatic component of the interactions investigated. Furthermore, they illustrated the need to expand the existing datasets beyond organo-meta1lic compounds, and include more common organic solvents. Results from X-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM) analysis of the model substrate, grade 2 titanium, pretreated via chromic acid (CAA) or sodium hydroxide anodization (PSHA), confirmed that oxides of very similar topology can be produced. Indicator dye studies revealed the CAA-Ti had a surface pH of below 3.0 and the PSHA-Ti had a surface pH of above 8.0. Bonds constructed from these analyzed materials were tested in peel and both systems exhibited good adhesion. However, the bonds in which favorable interactions were possible demonstrated superior interfacial performance. This improvement was seen in the bond’s ability to resist adhesive (interfacial) failure at debond rates at which other bonds failed. When the test geometry was changed such that the stress intensity at the interface was increased, the bonds in which acid/base interactions were favorable supported a higher peel load.
Ph. D.

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Hefer, Arno Wilhelm. "Adhesion in bitumen-aggregate systems and quantification of the effect of water on the adhesive bond." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1457.

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This research is intended to contribute toward the understanding, development, and implementation of a more fundamental design process for bituminous pavement materials, utilizing thermodynamic properties of the materials involved. The theory developed by van Oss, Chaudhury and Good forms the basis of this research. Optimization of techniques to characterize surface energy, as well as consideration and evaluation of additional factors that influence adhesion in the presence of water, are pursued. A synthesis of theories and mechanisms of bitumen-aggregate adhesion is presented, and existing and potential techniques for surface energy characterization are reviewed to establish firm background knowledge on this subject. The Wilhelmy plate technique was scrutinized and improved methodologies and analysis procedures are proposed. Inverse gas chromatography (IGC) is introduced as an alternative technique. A reasonable comparison of total surface energy values form these techniques with mechanical surface tension values were found. Results suggest that bitumen surface energies do not vary substantially. Inability of these techniques to detect the effect of a liquid additive is rationalized by the potential surface energy concept. Suggestions for a more realistic characterization of bitumen polar surface energy components are presented. A static gravimetric sorption technique was employed to characterize aggregate surface energies. Dynamic vapor sorption was identified as a candidate alternative technique for aggregate surface energy characterization. A study on the effect of pH on surface energy components of water revealed that this effect is practically negligible. Calculation of the free energy of electrostatic interaction (DGEL) indicated that this term contributes less than 1% to the total free energy of adhesion. Despite this finding, it is shown that DGEL alone is able to distinguish moisture sensitive mixtures. The significance of electrical phenomena at the interface is elucidated through another mechanism following the work of M.E. Labib. The relationship between pH and electron donor-acceptor properties of aggregate surfaces is presented. The Labib approach potentially offers the solution to quantify the effect of pH on adhesion. In addition, it should be possible to resolve issues with the acid-base scale proposed by the founders of the current theory, by replacing it with a more absolute donor-acceptor scale.

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Marcus, Hilda. "Adherence of Pseudomonas aeruginosa to perfused tracheal epithelium : adhesin [i.e. adhesion] - receptor interactions /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487259580261697.

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Ellison, Matthew M. "Metal/polymer interactions in polyimide adhesives." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-08282003-155323/.

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Nussbaum, Ralph. "Surface interactions of wood with adhesives and coatings /." Stockholm, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3229.

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Nobbs, Angela Helen. "Interactions of streptococci with epithelial cells." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268782.

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Haggar, Axana. "Interaction between Extracellular adherence protein (Eap) from Staphylococcus aureus and the human host." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-496-1/.

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Boks, Niels P. "Bacterial interaction forces in adhesion dynamics." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 2009. http://irs.ub.rug.nl/ppn/.

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Werrett, C. R. "Inelastic Electron Tunnelling Spectroscopy (IETS) of saline coupling agents." Thesis, De Montfort University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377709.

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Judge, Heather. "Studies on platelet-leucocyte interactions." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324698.

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Strand, Sabina P. "Interactions between Chitosans and Bacteria : Flocculation and Adhesion." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-108.

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Singla, Saranshu. "Consequences of Interfacial Interactions on Adsorption and Adhesion." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1541714540493631.

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Bjerketorp, Joakim. "Novel adhesive proteins of pathogenic Staphylococci and their interaction with host proteins /." Uppsala : Dept. of Microbiology, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a451.pdf.

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Johnson, Casey P. "A Mathematical Model of Adhesion Interactions between Living Cells." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd914.pdf.

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Drobni, Mirva. "Adhesion-related interactions of Actinomyces and Streptococcus biofilm bacteria." Doctoral thesis, Umeå : Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-860.

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Hoellerer, Maria Kerstin. "Structural studies of the interactions of focal adhesion kinase." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418531.

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Girard, Henri-Louis Jean-Paul. "Interactions at interfaces across scales : from adsorption to adhesion." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/128341.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, February, 2020
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 109-119).
The interface between two phases is a prime site for exchanges to occur: from heat or mass transfer to the adsorption of contaminants. This work explores a range of interactions at interfaces across scales, from the adsorption of molecules on substrates to the adhesion of ice on solids. Surface engineering is used to tailor the physicochemical properties of surfaces (microstructure, roughness, chemical functionalization, and charge) to achieve the desired behavior. First, macroscopic features are introduced on superhydrophobic substrates to restrict transport phenomena between an impacting droplet and a solid surface. Then, the adsorption of organic contaminants from oil is investigated as a function of surface functionalization and a hybrid liquid-solid substrate is developed to mitigate deposition. At the macroscale, the ice-solid interface is examined and two separate approaches that combine adhesion reduction with a robust surface design to make them practical for use in harsh environments are demonstrated. Finally, the directed adsorption of proteins is used to build in situ templates that enhance the nucleation rate of crystals for applications in protein-based drug manufacturing.
by Henri-Louis Jean-Paul Girard.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Mechanical Engineering

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29

Eberhard, Thomas Herrman. "Bacterial interactions with the fibrinolytic system and with the extracellular matrix /." Stockholm, 1999. http://diss.kib.ki.se/1999/91-628-3422-3/.

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Su, Bin. "Interaction between gastric pathogen Helicobacter pylori and host cells /." Stockholm, 1999. http://diss.kib.ki.se/1999/91-628-3423-1/.

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31

Merien, Fabrice. "Interactions entre les leptospira pathogenes et les cellules eucaryotes (doctorat : microbiologie)." Paris 11, 2000. http://www.theses.fr/2000PA114804.

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32

Brown, Marena Dessette. "Sickle cell-endothelial interactions : modulation of cell adhesion molecule expression." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/11306.

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Silkowski, Helena. "Solution structure and interactions of T-lymphocyte cell adhesion molecules." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362055.

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Wilson, Michael Charles. "Connections Between Acid-Base Interactions and the Work of Adhesion." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1586439939982267.

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35

Devaka, K. Weerakoon Cheung H. Tak. "Interaction of macrophages with the basement membrane." Normal, Ill. Illinois State University, 1995. http://wwwlib.umi.com/cr/ilstu/fullcit?p9603526.

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Thesis (Ph. D.)--Illinois State University, 1995.
Title from title page screen, viewed May 8, 2006. Dissertation Committee: Hou Tak Cheung (chair), David W. Borst, Herman E. Brockman, Alan J. Katz, Anthony J. Otsuka. Includes bibliographical references (leaves 98-110) and abstract. Also available in print.

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Messent, Anthea Jane. "Novel roles for matix metalloproteinases in cell-matrix interactions." Thesis, Open University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242514.

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Klittich, Mena R. "Surface Interactions with Hierarchical Nanostructures: From Gecko Adhesion to Thermal Behavior." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1499440265902425.

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DIAB, ASSEF MOUNA. "Role pro-inflammatoire des adhesines dans les interactions bacteries/cellules epitheliales." Strasbourg 1, 1997. http://www.theses.fr/1997STR15111.

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39

Plunkett, Mark. "Dynamic interactions of interfacial polymers." Doctoral thesis, KTH, Chemistry, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3395.

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The relationship between the amount and conformation of apolymer at the solid-liquid interface, and the resultinginteraction forces between two such surfaces has beeninvestigated. With a degree of control of the polymerconformation, by varying the temperature, solvent quality,polymer charge density etc, it has been possible to measure andinterpret the resulting changes in the surface interactions.The recurring themes of dynamics and hydrodynamics have beencontinually considered due to the large range and viscoelasticnature of the polymeric systems.

The polymeric systems investigated in this thesis are, poly(N-isopropylacrylamide), poly (12-hydroxystearate) and a seriesof AM-MAPTAC polyelectrolytes with variable chargedensities.

Adsorption and conformation of polymers have beeninvestigated by the novel QCM instrument. By comparison tosimultaneously measured energy loss information, a greaterunderstanding of the conformation of the polymer has beengained, both as a function of layer build-up during initialadsorption, and as a result of induced conformational changes.Comparing the results toin situsurface plasmon resonance and subsequent x-rayphotoelectron spectroscopy measurements, the relativeconcentration of polymer within the layer is determined. Inaddition, efforts have been made to extend the scope of thetechnique, in such ways as measuring with QCM as a function oftemperature and deriving viscoelastic properties. The later isstill to be achieved in absolute terms for polymer layers inliquid environments, yet both the principle and experimentalcapabilities have been shown.

Normal interaction forces have been measured as a functionof solvation of the polymer layer, for both adsorbed andgrafted polymer layers. For fully solvated (steric) polymerlayers, which can act as colloidal stabilisers, the dynamics ofthe repulsive force, including hydrodynamics have beeninvestigated. The same has been achieved for collapsed polymerlayers, in which the dynamic adhesion has also beeninvestigated. The effect on the adhesion of three differentdynamic mechanisms has been determined (which, like the surfaceforces, depend on the polymer conformation andviscoelasticity). These dynamic mechanisms are based onbridging forces, polymer entanglement and a viscoelasticbulkresponse from the surface layers.

Lateral or friction measurements have also been completed.The effect of load and rate have been investigated as afunction of both the polymer charge density and the underlyingsubstrate, which result in a variable conformation and bindingstrength to the substrate. This has resulted in a complexaddition of numerous mechanisms, the dominant mechanism beingdetermined by the binding strength to the surface, polymerconformation and viscoelasticity. The results have shown thatadsorbed polymer layers can be used to both increase anddecrease friction, and to change the direction of the ratedependence.

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VERNIER, GEORGENTHUM ALINE. "Etude des interactions moduline des streptocoques viridans oraux : cellules endotheliales ; role dans l'inflammation." Strasbourg 1, 1997. http://www.theses.fr/1997STR15112.

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41

Hebert, Kathryn S. "Investigation of Anaplasma phagocytophilum and Anaplasma marginale adhesin-host cell interactions." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4130.

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Anaplasma phagocytophilum and A. marginale are the etiologic agents of bovine anaplasmosis and human granulocytic anaplasmosis, respectively. As obligate intracellular pathogens, binding and entry of host cells is a prerequisite for survival. The molecular events associated with these processes are poorly understood. Identifying the adhesins mediating binding, delineating their key functional domains, and determining the molecular determinants to which they bind not only benefits better understanding of Anaplasma spp. pathobiology, but could also benefit the development of novel approaches for protecting against infection. We previously demonstrated that A. phagocytophilum outer membrane protein A (ApOmpA) is critical for bacterial binding and entry host through recognition of α2,3-sialic acid and α1,3-fucose of its receptors, including 6-sulfo-sLex. In this study, we determined that two amino acids, G61 and K64, within its binding domain (ApOmpA59-74), are essential for ApOmpA function. We also confirmed the ability of ApOmpA to act as an adhesin and invasin as it conferred adhesiveness and invasiveness to inert beads. We next extended our studies to A. marginale as it also expresses OmpA (AmOmpA) and its role in infection has not been studied. Molecular models of ApOmpA and AmOmpA were nearly identical, especially in the ApOmpA binding domain and its counterpart in AmOmpA. Antisera raised against AmOmpA or its putative binding domain inhibit A. marginale infection. AmOmpA G55 and K58 are contributory and K59 is essential for AmOmpA to bind to host cells. AmOmpA binding is dependent on α2,3-sialic acid and α1,3-fucose. Coating inert beads with AmOmpA conferred the ability to bind to and be taken up by host cells, confirming that it acts as an adhesin and invasin. 6-sulfo-sLex is dispensable for AmOmpA binding and A. marginale infection. ApOmpA works cooperatively with Asp14 (14-kDa A. phagocytophilum surface protein) to promote optimal infection of host cells. We found that Asp14 is conserved across A. phagocytophilum strains and in A. marginale and confirmed the ability of Asp14 to act as an adhesin and invasin as it conferred adhesiveness and invasiveness to inert beads. Collectively, this work advances our understanding of A. phagocytophilum and A. marginale adhesion and invasion of host cells.

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42

Nicholson, Martin William Michael. "Molecular analysis of the leukocyte cell-surface adhesion protein L-selectin." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260752.

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43

Palm, Daniel. "Adaptive responses during Giardia-host interactions /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-207-1/.

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44

Bornais, Judy Ann Karpecki. "Lymphocyte/endothelial cell adhesion, metal ions and VLA-4/VCAM-1 interactions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ42052.pdf.

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45

Buckley, Christopher Dominic. "Molecular analysis of IgSF-integrin interactions : their role in leukocyte endothelial adhesion." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320117.

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46

Gardner, M. J. "Adhesion molecules in the interactions of ovarian tumour cells and mesothelial cells." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336754.

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47

Pfaff, Dennis. "EphB-ephrinB interactions controlling monocyte and tumor cell adhesion to endothelial cells." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:25-opus-50510.

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48

Ye, Zhou. "Effect of Nanoscale Surface Structures on Microbe-Surface Interactions." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/85387.

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Bacteria in nature predominantly grow as biofilms on living and non-living surfaces. The development of biofilms on non-living surfaces is significantly affected by the surface micro/nano topography. The main goal of this dissertation is to study the interaction between microorganisms and nanopatterned surfaces. In order to engineer the surface with well-defined and repeatable nanoscale structures, a new, versatile and scalable nanofabrication method, termed Spun-Wrapped Aligned Nanofiber lithography (SWAN lithography) was developed. This technique enables high throughput fabrication of micro/nano-scale structures on planar and highly non-planar 3D objects with lateral feature size ranging from sub-50 nm to a few microns, which is difficult to achieve by any other method at present. This nanolithography technique was then utilized to fabricate nanostructured electrode surfaces to investigate the role of surface nanostructure size (i.e. 115 nm and 300 nm high) in current production of microbial fuel cells (MFCs). Through comparing the S. oneidensis attachment density and current density (normalized by surface area), we demonstrated the effect of the surface feature size which is independent of the effect on the surface area. In order to better understand the mechanism of microorganism adhesion on nanostructured surfaces, we developed a biophysical model that calculates the total energy of adhered cells as a function of nanostructure size and spacing. Using this model, we predict the attachment density trend for Candida albicans on nanofiber-textured surfaces. The model can be applied at the population level to design surface nanostructures that reduce cell attachment on medical catheters. The biophysical model was also utilized to study the motion of a single Candida albicans yeast cell and to identify the optimal attachment location on nanofiber coated surfaces, thus leading to a better understanding of the cell-substrate interaction upon attachment.
Ph. D.

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49

David, Manu Susan. "Complex Interactions Between Osteosarcoma Cells and Fibroblasts." Thesis, The University of Sydney, 2011. http://hdl.handle.net/2123/8242.

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This thesis investigates interactions between neoplastic cells in tumours, and the stromal-host cells with which the neoplastic cells must cooperate in order to survive. Earlier work upon which this thesis is based, established contact dependent induction of apoptosis in endothelium by SAOS-2 osteosarcoma cells (McEwen et al., 2003). This was quantitated by detecting a reduction in endothelial cell culture density (McEwen et al., 2003), but when similar experiments were performed with human gingival fibroblasts (HGF), no apoptosis was detectable despite there being an apparent reduction in HGF cell culture density (Huynh, 2007). This thesis confirms that the seeming disappearance of HGF co-cultured with SAOS-2 can be accounted for by transfer of SAOS-2 membrane marker to HGF, and explores some aspects of how the microenvironment determines specific cellular interactions between neoplastic and stromal cells. Chapter 1 summarizes background literature relevant to the work described in the remaining thesis. Chapter 2 investigates the necessary first step of cell adhesion in interaction between SAOS-2 and HGF. An adhesion assay was established in which SAOS-2 are applied to monolayers of HGF, and gently washed prior to cell counts. SAOS-2 binding to HGF was markedly increased by pre-treatment of HGF with TNF-α in a dose dependent manner, and as was seen in Chapter 3, this was found to be mediated by ICAM-1 expressed by HGF. Surprisingly, SAOS-2 pre-treated with TNF-α had reduced binding to TNF-α treated HGF, indicating that for this interaction, SAOS-2 must have a ‘permissive cellular history’ in which they have not been stimulated by TNF-α, and this was recognized as having implications regarding similar binding events in-vivo, where neoplastic cells at the invading front of tumours migrate from one micro-environment to another. Chapter 3 examines the effect of TNF- pre-treatment upon the ability of SAOS-2 to reduce the apparent culture density of HGF. Reduction in the apparent culture density of HGF was seen in broad proportion to the increased binding of SAOS-2 to HGF mediated by TNF-α. Also, work in this chapter excluded the possible contribution of autophagy to loss of HGF in co-culture with SAOS-2. Chapter 4 describes studies in which HGF and SAOS-2 were pre-labelled with a range of fluorescent markers for plasma membranes, cytoplasm and nuclear material. Co-culture of these cells was accompanied by the appearance of dual labelled cells, while quantitative analysis was performed to assess patterns of label exchange across cell types. Exchange of both plasma membrane and cytoplasmic markers was observed in these cultures, although plasma membrane marker exchange was more prevalent as judged by the proportion of dual labelled cells seen. No cells with both nuclear labels were found. The direction of label exchange was strongly influenced by the specific labels used in given experiments, so that it was not possible be certain whether bulk transfer of membrane or cytoplasm had occurred. Nonetheless, it was possible to conclude with reasonable confidence that continuity in plasma membranes and cytoplasm was established between HGF and SAOS-2, sufficient for the exchange of significant quantities of labelled proteins in the case of cytoplasm, as well as for membrane embedded alkaline phosphatase from SAOS-2 to HGF and lipophilic membrane dyes across both cell types. This ‘cellular sipping’ by SAOS-2, was suggested as a potential mechanism overcoming the effects of a progressively deranged neoplastic genome. It was also recognized that the generation of populations of cells expressing proteins of mixed origin would increase tumour diversity, with potential to affect tumour progression. In addition, quantitative morphological assessment was performed of cell circularity and cell surface area profile, as an indirect measure for phenotypic state, and the finding that dual labelled cells expressed morphological properties intermediate to HGF and SAOS-2 suggested phenotypic impact of cellular sipping. The influence of TNF-α was also studied in this chapter, which was found to increase the extent of cellular sipping. In Chapter 5, the effect of co-culture of SAOS-2 upon HGF pre-treated with TNF-α with regard to cytokine synthesis was examined in both: direct co-culture; and also in co-cultures where SAOS-2 and HGF were separated by transwell membranes. SAOS-2 made negligible contribution to levels of any of the cytokines studied (IL-6, GM-CSF, G-CSF, FGF). However, SAOS-2 did increase production by TNF-αpre-treated HGF of IL-6, GM-CSF, and G-CSF in transwell co-cultures, despite having the opposite effect in direct co-cultures where SAOS-2 were in intimate contact with HGF. In summary, results in this thesis demonstrate that SAOS-2 and HGF interact intimately, through the establishment of continuity between plasma membranes and cytoplasm, and that the resulting transfer of membrane and cytoplasmic material produces four ultimate populations of cells in co-culture being: HGF; SAOS-2; HGF with SAOS-2 membrane and cytoplasmic elements; and SAOS-2 with HGF cytoplasmic and membrane elements. Furthermore, a role for TNF-α in facilitating HGF and SAOS-2 binding via ICAM-1, as well as in mediating exchange of material between cells is demonstrated. The complexity of these interactions is underscored by the opposing effect upon SAOS-2 binding to HGF of pre-treatment of either cell type with TNF-α, as well as by the opposite cytokine synthetic profile of HGF co-cultured in direct contact with SAOS-2, as opposed to separated by a transwell membrane. These observations support the idea of there being ‘permissive microenvironments’ for a range of interactions between stromal and neoplastic cells, as well as the idea of a ‘permissive cellular history’ for some responses. The paracrine and contact dependent interactions identified support subversion of stromal cell function in support of neoplastic cells. Also, cellular sipping by neoplastic cells seems to provide a novel mechanism through which malignant neoplastic cells with irreparably damaged genomes may be able to gain survival advantage by capturing normal cytoplasmic and membrane elements from surrounding stromal cells. In addition, findings relating to permissive microenvironments, permissive cellular histories, and the generation of complex cell populations through cellular sipping, provide further explanation of architectural and cytological pleomorphism in malignant neoplasms, till now attributed primarily to the emergence of divergent sub-clones of neoplastic cells through the accumulation of genetic lesions.

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Smith, Diane Elizabeth. "Adhesion of Mycobacteria: Capture, Fouling, Aggregation." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1542537888485749.

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Dissertations / Theses on the topic 'Adhesive Interactions'

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