Dissertationen: „CLST“

1

Rara, Angela Dominique Sarmiento. "Rolling Shear Strength and Modulus for Various Southeastern US Wood Species using the Two-Plate Shear Test." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/104017.

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Cross-Laminated Timber (CLT) is an engineered wood product made by laminating dimensional or structural composite lumber in alternating orthogonal layers. Compared to Canada and Europe, CLT is a novel product to the US. With the additions included in the 2021 International Building Code (IBC), CLT material properties, especially rolling shear, would need to be explored. The increasing demand for softwood lumber, along with the increase of demand of CLT panel production, could place a burden and surpass the domestic softwood supply. Rolling shear is a phenomenon that occurs when the wood fibers in the cross-layers roll over each other because of the shearing forces acting upon a CLT panel when it is loaded out-of-plane. This study used the two-plate shear test from ASTM D2718 to measure the rolling shear properties of various southeastern US wood species: southern pine, yellow-poplar, and soft maple. A secondary study was conducted, using the same two-plate shear test, to measure the rolling shear properties of re-manufactured southern pine for CLT cross-layer application. The soft maple had the greatest average rolling shear strength at 5.93 N/mm2 and southern pine had the lowest average rolling shear strength at 2.51 N/mm2. Using a single factor analysis of variance (ANOVA), the rolling shear strength values from soft maple were significantly greater than yellow-poplar, which was significantly greater than the southern pine. For the rolling shear modulus, the southern pine and soft maple were of equal statistically significant difference, and both were greater statistically significant different compared to the yellow-poplar. The most common failure found from testing was rolling shear. Master of Science Cross-Laminated Timber (CLT) is an engineered wood panel product, similar to plywood, constructed with solid-sawn or structural composite lumber in alternating perpendicular layers. The additions included in the incoming 2021 International Building Code (IBC) has placed an importance in expanding the research related to the mechanical and material properties of CLT. Also, with the increasing demand for softwood lumber and CLT panel production, the demand for the domestic softwood lumber could place a burden and surpass the domestic softwood supply. Rolling shear is a failure type that occurs when the wood fibers in the cross-layers roll over each other because of the shearing forces acting upon a CLT panel. This study used the two-plate shear test to measure the rolling shear properties of various southeastern US wood species: southern pine, yellow-poplar, and soft maple. A secondary study was conducted, using the same two-plate shear test, to measure the rolling shear properties of re-manufactured southern pine for CLT cross-layer application. The soft maple had the greatest average rolling shear strength at 5.93 N/mm2 and southern pine had the lowest average rolling shear strength at 2.51 N/mm2. Using a single factor analysis of variance (ANOVA), the rolling shear strength values from soft maple were significantly greater than yellow-poplar, which was significantly greater than the southern pine. For the rolling shear modulus, the southern pine and soft maple were of equal statistically significant difference, and both were greater statistically significant different compared to the yellow-poplar. The most common failure found from testing was rolling shear.

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2

Jones, J. R. "CLAT crystals." Thesis, Swansea University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637453.

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We report here the results of investigations into three related but distinct aspects of studies on montmorillonites. The first examines the alumina pillaring of montmorillonite by the introduction of the so-called 'Keggin ion' via cation exchange. The level of pillar precursor ion introduced is controlled by inducing layer charge reduction by controlled calcination. Previously, neither the effective charge on the Keggin ion nor the pillar densities achieved were known with any certainty since the analyses of Al and Si present substantial difficulty. We have introduced a new technique to calculate the number of pillars introduced which we call 'isomorphous metal dilution'. This is based on analysis of Fe3+ and Mg2+, which is achieved with accuracy. The results are self consistent and establish that the Keggin ion charge here is 3+ , not 7+ as assumed previously. The next section explores the possibility of incorporating more Li+ into the layers of Texas montmorillonite during the process of lithiation. It involved successive calcination of Li+ exchanged clay, base regeneration of cation exchange capacities, further Li+ exchange and calcination, etc. This was successfully carried out five times, and enhanced the level of lithiation. However, it was established that this reaches a limit. Suggestions are offered to account for this. These clays also showed high solvent stability as compared to the parent material, a distinct commercial benefit. Finally, the catalytic alkylation of thiophene, has been investigated. C3 to C6 alk-1-enes and alkan-1-ols were employed as alkylating reagents. The broad range of reaction products have been characterised by GC/MS and by a comprehensive gas chromatographic study based on structural dependences of retention volume. Alkanols were shown to represent inefficient reagents. Alkenes on the other hand gave results establishing that, by suitable adjustment of temperature and relative reactant concentrations, highly competitive product yields and selectivity compared to conventional catalysts may be produced.

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3

Jaishankar, Gayatri, Thomas M. Yohannan, and Roger Smalligan. "Draining Ears, Dizzying Clot." Digital Commons @ East Tennessee State University, 2009. https://dc.etsu.edu/etsu-works/8876.

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4

Asquith, Nathan Lee. "Extended D-E knob-hole interaction sites in fibrin polymerisation, clot formation and clot mechanics." Thesis, University of Leeds, 2019. http://etheses.whiterose.ac.uk/22624/.

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Background: Abnormal thrombus formation and occlusion of a vessel is one of the main events of cardiovascular disease. A main component of the thrombus is the protein fibrin, which is formed by proteolytic cleavage of its precursor fibrinogen by the serine protease thrombin. The cleavage of fibrinogen to fibrin releases fibrinopeptides from the E-region of the molecule which leads to the exposure of peptide sequences termed knobs A and B. The knobs A and B on one fibrin molecule are able to spontaneously interact to binding pockets (termed holes a and holes b) via hydrogen bonds forming half staggered protofibrils. These protofibrils laterally aggregate and form fibrin fibers, providing the clot its strength and stability. Recent molecular dynamic simulations have predicted that there are additional interactions involving amino acids gGlu323 with BLys58, gLys356 with BAsp61, and gAsp297 with BHis67, that surround the binding pocket and provide additional strength and stability to the 'classical' knob-hole contact. In this project I have termed these residues 'extended D-E knob-hole binding sites.' Aim: The aim of this project was to probe the importance of these extended knob-hole interactions in the process of fibrin polymerisation, clot structure and clot mechanics, using recombinant fibrinogen variants with mutations that abolish these electrostatic interactions. Methods: Four recombinant human fibrinogen variants and WT proteins were produced. The following variants with single point mutations in the g-chain of extended knob-hole binding region were produced: gD297N, gE323Q and gK356Q. A triple variant, gDEK (gD297N/gE323Q/gK356Q) with mutations in all residues involved was also produced. Each variant was tested for integrity by circular dichroism and SDS-PAGE. Turbidity and atomic force microscopy were used to study polymerisation kinetics, laser scanning confocal microscopy and scanning electron microscopy were used to study clot structure. Light scattering methods were used to study intrafibrillar protein structure, and clot mechanics was studied using an in-house micro-rheometer. Results: Longitudinal protofibril growth was disrupted for all variants except gK356Q at early stages of polymerisation, but normalised at later time points. Vmax was reduced for all variants. gDEK and gE323Q produced denser clots, whereas gD297N and gK356Q were similar to WT. All variant clots had significantly thinner fibers compared to WT. All variants were slower to lyse, with the exception of gD297N. Clot visco-elastic analysis showed that γDEK was more readily deformable (loss tangent, tanδ), at low frequencies but single mutant variants were unchanged at all frequencies compared to WT. Conclusion: I produced pure and intact recombinant human fibrinogens with mutations at the extended knob-hole binding sites. These data provide clear evidence for the role of extended D-E interactions in supporting the classical knob-hole binding during fibrin formation. Furthermore, the extended D-E interactions were shown to alter clot structure and clot mechanics. Additional studies with these variants in the presence of cells and other vascular components may further elucidate the importance of extended knob-hole interactions in haemostasis and thrombosis.

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Richardson, Victoria Rebecca. "Identification and characterisation of novel plasma clot components." Thesis, University of Leeds, 2012. http://etheses.whiterose.ac.uk/4153/.

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Plasma clot structure/function is a major determinant in cardiovascular disease risk and severity. Plasma proteins are incorporated into plasma clots via binding and factor XIII-dependent cross-linking, with complement C3 and factor H previously identified as plasma clot components using proteomics. The aim of this current project was to validate the role of C3 and factor H in fibrin structure and function and to establish a proteomics method for the identification of novel factor XIII substrates. C3 did not affect fibrin structure; however C3 induced a concentration-dependent prolongation of fibrinolysis. C3 was cross-linked to fibrin within purified and plasma clots and bound to plasma clot components. C3 was a substrate for plasmin, with cleavage occurring in the presence and absence of fibrin. C3 also influenced angiostatin production and t-PA and plasminogen interactions within fibrin clots to prevent plasminogen cleavage and plasmin generation. All of these interactions were found to influence fibrinolysis. Whereas factor H was confirmed to be a plasma clot component, was associated with inflammation and fibrin structure and function but was not associated with complement activation in individuals at risk of cardiovascular disease. Further in vitro analyses found that factor H did not affect fibrin structure or fibrinolysis. Factor H was not cross-linked to fibrin in purified and plasma clots, but did form homodimers in the presence and absence of fibrin and factor H was a substrate for thrombin and plasmin, with cleavage occurring within fibrin clots. The proteomic techniques were established for the identification of factor XIII substrates however no novel proteins were identified using these methods, suggesting the sensitivity of the technique may be insufficient to detect novel proteins. This study has added to the growing body of evidence which suggests complement and coagulation pathways interact for the purposes of preventing blood loss and pathogen invasion.

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6

Pan, Xiaoxi. "Fibrin clot structure alterations after particulate matter exposure." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/14310/.

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Particulate matter (PM) as an important part of ambient air pollution has been associated with increased risks of cardiovascular diseases. Fibrin clot structure alteration is an emerging risk factor of many cardiovascular diseases, especially thrombosis. Therefore, the aim of this study was to investigate whether and how air particulate matter affects fibrin clot structure and endothelial cell behaviour. Turbidity assay, turbidity lysis assay and laser scanning confocal microscopy were used to analyse clots formed from normal pooled plasma or purified fibrinogen, in the presence of varying concentrations of PM. It was found that clots formed from plasma with higher concentrations of particles led to prolonged lysis time compared to control. No differences were seen for clots formed from fibrinogen. In a study of clots formed from plasma samples collected as part of a previous study on the effects of air pollution on deep vein thrombosis (DVT), alterations were observed in clots formed from plasma of DVT patients exposed to high levels of PM compared to those exposed to low levels, but the same differences were not observed in clots formed from plasma of control subjects. To investigate the potential role of venous endothelial cells in moderating clot structure following exposure to PM, human umbilical vein endothelial cells (HUVEC) were treated with PM for 24 hours and clots subsequently formed on the cells. Clots formed from plasma on the treated cells were altered compared to controls. RT-PCR and ELISA results showed increased gene expression of tissue factor (TF), protein expression of von Willebrand Factor (VWF) and plasminogen activation inhibitor-1 (PAI-1) and decreased thrombomodulin mRNA expression which were consistent with changes observed in clot structure. Engineered SiO2 nanoparticles caused denser clot structure in clots formed from normal pooled plasma. The gene expression of thrombomodulin was inhibited by SiO2 nanoparticles, but there were no significant difference in the TF mRNA expression between control and treated cells. Silica NPs caused increased concentrations of VWF, but not PAI-1 produced by endothelial cells. The results presented here show that PM can induce changes to clot structure and function, and that changes in gene expression induced in endothelial cells may be a mechanism by which a prothrombotic state is induced in response to PM exposure. Furthermore, some, but not all, similar changes were observed in clots and cells exposed to SiO2 nanoparticles, raising the possibility that such engineered nanoparticles may also have the potential to contribute to cardiovascular toxicity.

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7

Rousselot, Marie. "A combined field and laboratory study of clast ploughing /." Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16471.

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8

Courval, Isabelle de. "L'utilisation de l'informatique dans la pratique professionnelle en CLSC." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60710.pdf.

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9

Lindgren, Malin. "Molecular and functional characterization of the insect hemolymph clot." Doctoral thesis, Stockholm : Department of Molecular Biology and Functional Genomics, Stockholm University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7310.

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10

Livas, Charalampos. "Building extension through additional CLT storeys." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-82227.

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In the last decade, the use of cross-laminated timber (CLT) panels as load bearing elements have become a usual solution for buildings and structures with an upward trend internationally. This is because CLT has brilliant physical and mechanical properties and it is also an eco-friendly and renewable material. In addition, the prefabricated nature of the CLT panels in a controlled environment increases the overall building speed, reduces dramatically the erection time, and makes it an even more competitive structural material compared to more traditional ones like concrete and steel. Up until now, timber as a building material has mainly been used for roofs and pergolas in Greece. Concrete and steel have traditionally been the dominant building materials over the years. Timber is not such competitive mainly because there is not enough knowledge of abouttimber buildings. The fact that Greece is not a sawn timber producer affects this trend. Nowadays, the simple and cheap import of sawn timber, as well as the sensitiveness about the environment, are strong factors for introducing timber buildings to Greece. There is already a great demand for timber buildings, and an increase in the requests is expected.CLT panels are used in a wide spectrum of structural applications. They are used as structural components for houses, offices, multi-story buildings, schools, industrial halls, sports halls, and special structures [4]. Another innovative application of CLT is the renovation through vertical expansion with additional floors to existing buildings. This new and promising trend is becoming more and more frequent, especially in developing cities where there is a need for new houses in limited space. The low density of CLT and so the low overall weight of the additional structure, makes the CLT components a robust building solution for vertical renovation since there is usually no need for reinforcement of the foundations of the current building [15]. The aim of this study is to provide the author with the opportunity to deepen his knowledge regarding the special characteristics of CLT as a building material as well as to understand its mechanical properties and the theories which describe them. In addition, this study constitutes the first attempt at modeling and designing a timber structure made with CLT panels. Therefore, the knowledge gained about the special features in CLT modeling is a fundamental task. Finally, since the design of the CLT structure is based on the European design rules for buildings, the engagement with the appropriate Eurocodes, i.e. Eurocode 0, 1 & 5, is another critical task in this study. The structure under consideration is a two-story CLT structure which is a vertical expansion of a current composite (concrete-steel) building. The first additional floor will be used as an office area and the second one as a typical family house. Both additional floors are made of CLT elements and, where is necessary, glulam beams and columns are considered as reinforcement of the CLT panels and as supports, respectively. The design method includes finite element analysis (FEA) which is performed by the commercial structural softwareDLUBAL – RFEM [8]. In this study, the latter software is chosen for the design and the analysis of the structure since it is specialized software for timber structures made of CLT elements.

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11

Dreyer, Craig William. "Clast cell activity in a model of aseptic root resorption." Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phd778.pdf.

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12

Mackinnon, Charlotte M. "Molecular cloning of human complement component Cls." Thesis, University of Aberdeen, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327928.

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Cls cDNA clones, which together contained the entire coding region of the protein, were isolated from two human-liver cDNA libraries. The initial Cls clones were identified using a synthetic oligonucleotide probe which corresponded to a region of low degeneracy near the C-terminus of the Cls catalytic chain. Fragments of the Cls cDNA were used to screen a cosmid library in an attempt to isolate the Cls gene, but this proved unsuccessful and no positive clones were isolated. The complete primary sequence of Cls revealed that the homology between the Cls and Clr catalytic chains also extends throughout their non-catalytic chains. Like Clr, Cls can be divided into six structurally independent domains of which the sixth represents the catalytic B chain. Domains I and III in the A chain of Cls are internally homologous, as are domains IV and V. The latter domains are homologous to the internally repeating 60-residue sequences found in Factor B, C2 and other proteins. Domain II of Cls is similar to the 40-residue repeat sequences found in epidermal growth factor precursor and many of the vitamin K-dependent proteins. The assignment of these domains to the different regions of Cls tertiary structure has still to be achieved, but studies in this area should be facilitated now that the complete primary sequence for the Cls zymogen is available.

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Harmachova, Karolina. "Vibration performance of hybrid steel-CLT floors." Thesis, KTH, Byggnadsmaterial, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192475.

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In the light of today’s effort to achieve sustainable future of the planet, timber as building material makes a comeback on the construction market. Since the requirements on the buildings and the internal comfort increase, there is a need for finding new solutions and products; one of them is cross-laminated timber (CLT), which has the potential to be used for high-rise buildings due to its mechanical properties. The aim of this work was to study the vibration performance of CLT floors as it is often the governing factor in design of CLT structures unlike for other common building materials. The orthotropic mechanical properties of CLT were determined by the shear analogy method and verified with a finite element (FE) model of a simply supported beam compared to hand calculations of shear forces, bending moments and deflections. The properties based on Timoshenko’s approach were evaluated as less precise regarding the deflection. The non-composite structural behaviour of a steel-CLT hybrid floor structure was predicted for FE dynamic analysis based on a comparison between modelling exercise and hand calculations. Two different methods, the Concrete Society (SC) and Steel Construction Institution (SCI) methods, both seemed to be applicable for determination of the response factor first since the mechanical properties are not used as input in the calculations. These two methods differ in certain aspects, and based on FE analysis of simply supported slab even the resulting response factor for the CLT differs significantly. Moreover, the hand calculation results were similar to those of the FE analysis for the CS method, but in less agreement for the SCI method. Nevertheless, it is not recommended to reject the latter method based on this study and further studies should be performed on real structures with response factor known from on-site measurements. A part of the first floor of Canary Wharf College was modelled and analysed, and previous measurements of the frequency and response factors enabled a validation of some assumptions. The SCI approach showed to be inadequate for this type of structure and therefore only the CS method was applied further. Analysis of the floor structures supported by walls demonstrated similar results from both the measurements and the dynamic analysis. However, if the floor slab was supported by beams, the response factor was significantly overestimated although on the conservative side. This difference suggests that the modelling of such conditions are not satisfactory. The CS method appears to assess correctly the magnitude of the response factor for CLT floors supported by walls but overestimates it in case of beam supports. The first finding shall be confirmed through analysis of other structures and a more extensive research should focus on the latter one to determine more exact behaviour of the model under different conditions.

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14

Namroud, Larsana, and Ellen Hansson. "Projektering av KL-träbjälklag i bostäder med hänsyn till spännvidd och ljudkrav." Thesis, Tekniska Högskolan, Jönköping University, JTH, Byggnadsteknik och belysningsvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-50168.

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Wood construction has increased in the recent years for apartment buildings consisting of four to five floors. Compared to other building materials, wood has great environmental benefits. For a building in a larger scale constructed in wood, cross-laminated timber, also known as CLT is an option. The technology for CLT originated in Sweden during the 1990s and since then the development has increased. CLT has excellent stiffness and strength properties. The design of a floor in CLT is important for how the building and the environment are perceived indoors. The wooden floor is about five times lighter than concrete, which means that measures are required to meet the sound requirements set by Boverkets building regulations in Sweden. This will affect the span. The aim of the project is to present a knowledge overview of CLT and for floor in CLT up to 9 meters in span, to compete with concrete floor in steel and prefabricated concrete frames. The study includes a quantitative methodology using three different data collection methods. These are literature study, document analysis and calculations. The literature study and the document analysis are based on scientific-and research articles, together with manuals. The calculations are carried out in Stora Enso's calculation program Calculatis by Stora Enso. The program follows Eurocode's design principles. The result of the study shows that a CLT-board with laminated beams gives greater span than just a CLT-board does. The calculation means that the plate must meet the deflection requirement L / 300. Research shows that construction with CLT is increasing and there is great potential to obtain a cost-effective reduction of the carbon footprint and at the same time improve the utilization of natural resources by replacing non-renewable building materials such as concrete and steel with CLT. In order to achieve the sound requirements that are established, the CLT floor must be dimensioned thicker and measures such as additional insulation. By looking at the results, the conclusion is drawn that CLT-floor may grow further to compete with concrete floor in the future. Currently the material is considered useful and environmental for smaller constructions for such as smaller houses, due to the sound insulation problem. For larger constructions with the similar problem can timber-concrete composite be an alternative. CLT-floor reinforced with glulam beams may be considered as a choice for larger and bigger constructions because the span widths increase, and the construction can withstand maximum deflection. The study is limited to mainly considering CLT but also a small amount of concrete and glulam. Vibrations and environmental risks such as moisture, sunlight and fire, are not considered. The calculations the work uses are based on Eurocode 5, dimensioning of wooden structures. Other types of design principles have been excluded.

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Eriksson, Richard, and Maria Karlsson. "Effect of birch in CLT elements : An investigation of how introducing birch effects the strength properties of CLT elements." Thesis, KTH, Bro- och stålbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280361.

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In this thesis, material properties for a CLT element have been examined with regard to the structure of theelement and its content of different types of wood. The focus has been on how Birch affects the properties,since its properties in shear are much better compared to the commonly used pine and spruce.Calculations have been made in python script within the Rhino 6 software and its Grasshopper plugin.Grasshopper basically works with coding but with a visual interface that is very user friendly. This programhas been used because of its parametric structure which makes changes in the structure very simple andthe whole model changes with the changes in parameters.The basis for the survey has been the following parameters:• Number of layers within the KL element• Widths of lamellae• Thicknesses of lamellae• Material properties of Birch, Pine and Spruce• Quotas between Birch, Pine and SpruceThe results show that the shear stiffness of the CLT-element increases with the amount of birch. The value ofthe G-moduli, however, does not only depend on the amount but the positioning as well. The shear stiffnessis the greatest when the birch is placed closest to the middle of the element.The conclusion made is that further investigation of the practical and economical aspects are required to makean informed decision about whether the use of birch or increased board width is the most efficient method ofimproving the shear stiffness of CLT.

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Baril, François. "L'évolution des pratiques d'approche communautaire en CLSC de 1994 à 1996." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq26154.pdf.

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17

Doutrelepont, Frédéric. "Un psychologue en CLSC exerçant auprès des jeunes de la rue /." Thèse, Trois-Rivières : Université du Québec à Trois-Rivières, 2007. http://www.uqtr.ca/biblio/notice/resume/30000451R.pdf.

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18

Wilhelmsson, Christine. "Proteomics of the Drosophila hemolymph clot and the function of transglutaminase /." Stockholm : Department of molecular biology and functional genomics, Stockholm university, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-26382.

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19

Danna, James G. "Experimental study of clast orientation in gravels deposited by unidirectional flow." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/57919.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1985. Microfiche copy available in Archives and Science. Bibliography: leaves 83-84. by James G. Danna. M.S.

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Doutrelepont, Frédéric. "Un psychologue en CLSC exerçant auprès des jeunes de la rue." Thèse, Université du Québec à Trois-Rivières, 2007. http://depot-e.uqtr.ca/1989/1/030000451.pdf.

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21

Mancha, André Luiz Pereira. "Wage differential between statutory and CLT public employees." reponame:Repositório Institucional do FGV, 2018. http://hdl.handle.net/10438/24643.

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Submitted by Andre Mancha (andre.mancha87@gmail.com) on 2018-08-29T20:32:07Z No. of bitstreams: 1 dissertation-eesp-fgv.pdf: 569610 bytes, checksum: 160598b7f611722cee28985a77177bb5 (MD5) Rejected by Joana Martorini (joana.martorini@fgv.br), reason: Fora das normas ABNT. on 2018-08-29T20:41:05Z (GMT) Submitted by Andre Mancha (andre.mancha87@gmail.com) on 2018-08-30T14:29:26Z No. of bitstreams: 1 dissertation-eesp-fgv (final).pdf: 964294 bytes, checksum: 82aaf5cc2fc6ee9324bf6de691484d44 (MD5) Approved for entry into archive by Joana Martorini (joana.martorini@fgv.br) on 2018-08-30T14:37:20Z (GMT) No. of bitstreams: 1 dissertation-eesp-fgv (final).pdf: 964294 bytes, checksum: 82aaf5cc2fc6ee9324bf6de691484d44 (MD5) Approved for entry into archive by Suzane Guimarães (suzane.guimaraes@fgv.br) on 2018-08-30T15:37:05Z (GMT) No. of bitstreams: 1 dissertation-eesp-fgv (final).pdf: 964294 bytes, checksum: 82aaf5cc2fc6ee9324bf6de691484d44 (MD5) Made available in DSpace on 2018-08-30T15:37:05Z (GMT). No. of bitstreams: 1 dissertation-eesp-fgv (final).pdf: 964294 bytes, checksum: 82aaf5cc2fc6ee9324bf6de691484d44 (MD5) Previous issue date: 2018-08-02 Since 1998 in the Public Administration there are statutory workers ('estatutários') and others hired by the CLT labor regime ('celetistas'). Thisfact occurs due the Constitutional Amendment number 19 , formulated that year, which has changed the article 39 of Brazilian Constitution. It allowed public entities to hire employees under CLT legislation. This situation lasted until 2007 when the Supreme Court of Brazil suspended such modification and so the original understanding of the Constitution was reestablished. This work intends to evaluate the wage differential between statutory and CLT employees by means of an econometric approach. Using a fixed effectsregression we have analyzed the impact of the labor regime upon public workers wages and using the Oaxaca-Blinder decomposition we quantified how much of such differential is due the labor regime and how much is due to the individual characteristics (education, tenure and others). There are evidences that CLT workers have in average wages R$ 310.00 lower than statutory. Controlling by occupation we also see a negative prize to CLT worker to all groups except by the High Skilled Workers that have a salary R$ 95.98 higher than the Statutory. Low Skilled Workers show the smallest differential (R$ 12.20) followed by Teachers and Researchers (R$ 85.27) and Technicians (R$ 97.11). The Oaxaca-Blinder decomposition shows that the largest part is not explained by endowments differences. The spending with wages and benefits to public employees is one of the main debates in the current scenario of fiscal adjustment facing the relevant increase of Public Debt in the last years. The Brazilian society has a perception that the Government has an excessive amount of workers and furthermore these onesreceive higher wages without a reasonable explanation when compared to similar occupations in private companies. At the end of 2017 the Brazilian Government presented an action plan to reduce the spending with wages and benefits of public employees. Among the proposals there were a decrease in the initial salary of public service and an increase in the public pension plan contribution. Desde o ano de 1998 coexistem na Administração Direta, Autarquias e Fundações Públicas, funcionários públicos estatutários e 'celetistas'. Esta situação decorre da Emenda 19, a qual alterou o artigo 39 da Constituição e permitiu que estas entidades contratassem funcionários pela CLT. Essa situação perdurou até o ano de 2007, quando o Supremo Tribunal Federal (STF)suspendeu liminarmente (ADI 2135) a nova redação e dessa forma restaurou a situação original, válida atualmente. Este trabalho se propõe a medir a diferença no salário entre servidores públicos estatutários e celetistas por meio de uma abordagem econométrica. Utilizando uma regressão de efeitos fixos foi analisado o impacto do regime de trabalho sobre o salário dos servidores e por meio da decomposição de Oaxaca-Blinder estimou-se quanto desta diferença decorre do regime de trabalho e quanto se deve às características dos indivíduos de cada grupo (escolaridade, experiência e outros). Há indícios de que os celetistas recebem um salário R$ 310.00 menor do que seus pares estatutários. Controlando os efeitos de cada profissão há um diferencial negativo para todas os celetistas exceto para os profissionais de alta qualificação os quais possuem um salário R$ 95.98 maior do que os estatutários. Com relação aos outros grupos, os profissionais de baixa qualificação apresentam o menor diferencial de salários (R$ 12.20) seguido por professores e pesquisadores (R$ 85.27) e técnicos (R$ 97.11). Na decomposição do diferencial a maior parte não decorre de diferenças nas características dos indivíduos de cada grupo. O impacto dos salários e benefícios de funcionários públicos sobre as contas públicas é um dos principais pontos debatidos dentre as propostas que englobam o plano de ajuste fiscal do Governo Brasileiro. A percepção atual da sociedade é que além do governo contar com um contingente significativo de servidores públicos, estes recebem maiores salários quando comparados a trabalhadores em atividades semelhantes na iniciativa privada. Nesse contexto o governo federal apresentou no final de 2017 uma série de medidas para adequação dos gastos com folha de pagamento de servidores públicos, dentre elas a redução do salário inicial e elevação da contribuição previdenciária destes trabalhadores.

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Pai, Sai Ganesh Sarvotham. "Force transfer around openings in CLT shear walls." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/51632.

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During an earthquake, shear walls can experience damage around corners of doors and windows due to development of stress concentration. Reinforcements provided to minimize this damage are designed for forces that develop at these corners known as transfer forces. In this thesis, the focus is on understanding the forces that develop around opening corners in cross laminated timber (CLT) shear walls and reinforcement requirements for the same. In the literature, four different analytical models are commonly considered to determine the transfer force for design of wood-frame shear walls. These models have been reviewed in this thesis. The Diekmann model is found to be the most suitable analytical model to determine the transfer force around a window-type opening. Numerical models are developed in ANSYS to analyse the forces around opening corners in CLT shear walls. CLT shear walls with cut-out openings are analysed using a three-dimensional brick element model and a frame model. These models highlight the increase in shear and torsion around opening corners due to stress concentration. The coupled-panel construction practice for CLT shear walls with openings is analysed using a continuum model calibrated to experimental data. The analysis shows the increase in strength and stiffness of walls, when tie-rods are used as reinforcement. Analysis results also indicate that the tie-rods should be designed to behave linearly for optimum performance of the wall. Finally, a linear regression model is developed to determine the stiffness of a simply-supported CLT shear wall with a window-type opening. This model provides insight into the effect of various geometrical and material parameters on the stiffness of the wall. The process of model development has been explained, which can be improved further to include the behaviour of anchors. Applied Science, Faculty of Civil Engineering, Department of Graduate

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Fuchs, Franz Xaver. "Clock-feedthrough compensation in MOS sample-and-hold circuits." Thesis, University of Plymouth, 2001. http://hdl.handle.net/10026.1/2354.

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All MOS sample-and-hold circuits suffer to a greater or lesser extent from clock-feedthrough (CLFT), also called charge-injection. During the transition from sample to hold mode, charge is transferred from an MOS transistor switch onto the hold capacitor, thus the name charge-injection. This error can lead to considerable voltage change across the capacitor, and predicting the extent of the induced error potentials is important to circuit designers. Previous studies have shown a considerable dependency of CLFT on signal voltage, circuit impedances, clock amplitude and clock fall-time. The focus of this work was on the signal dependency of the CLFT error and on the CLFT induced signal distortion in open-loop sample-and-hold circuits. CLFT was found to have a strongly non-linear, signal dependent, component, which may cause considerable distortion of the sampled signal. The parameters influencing this distortion were established. It was discovered that distortion could be reduced by more than 20dB through careful adjustment of the clock fall-rate. Several circuit solutions that can help reduce the level of distortion arising from CLFT are presented. These circuits can also reduce the absolute level of CLFT. Simulations showed their effectiveness, which was also proven in silicon. The CLFT reduction methods used in these circuits are easily transferable to other switched-capacitor circuits and are suitable for applications where space is at a premium (as, for example, in analogue neural networks). A new saturation mode contribution to CLFT was found. It is shown to give rise to increased CLFT under high injection conditions.

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Vanden, Hoek Amanda Lynne. "Novel function of coagulation factor Xa : conversion into a clot-dissolving cofactor." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36854.

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PLASMIN-MEDIATED CONVERSION OF FXa INTO A CLOT-DISSOLVING COFACTOR. Factor Xa (FXa) is an essential blood clotting enzyme. A previously identified FXa derivative, Xa33/13, is generated by two distinct cleavages by the clot-dissolving (fibrinolytic) enzyme, plasmin. FXa is first converted to FXaβ by excision of a small C-terminal peptide and then proteolyzed at Lys330 in the autolysis loop to yield Xa33/13, which cannot participate in clotting. Instead, these cleavages confer novel fibrinolytic function to Xa33/13 as a tissue plasminogen activator (tPA) cofactor, thereby accelerating plasmin generation. To understand the importance of each cleavage and the role of individual residues in this functional conversion of FXa, five mutants were generated by mutation of basic residues to glutamine: Lys330 and four residues in the β-peptide region. Mutation at Lys330 prevented autolysis loop cleavage, and this mutant dissolved purified fibrin clots faster than plasma-derived FXa derivatives. Additionally, no basic residue within the β-peptide was uniquely targeted by plasmin and no single-point mutation in this region prevented subsequent autolysis loop cleavage. FX-DEFICIENT PATIENT. Factor X (FX) can be activated by two separate protein complexes, known as the initiating (extrinsic) and amplifying (intrinsic) tenases, which are assembled during coagulation. I describe a FX-deficient patient with a novel compound heterozygous mutation associated with differential clotting pathway function. Quantification of plasma FX antigen revealed 15 % of normal, which was consistent with extrinsic pathway activity. Intrinsic pathway activity was reduced to 5 % of normal, suggesting an activatable specific activity 3-fold lower than expected for this branch of the clotting pathway. DNA sequence analysis identified two heterozygous mutations: (1) a previously reported mutation that disrupts the splice site between exons I and II; (2) a novel mutation resulting in an Arg386Cys substitution in the protease domain. I propose that alternate disulfide bond formation and protein folding may reduce circulating FX antigen levels. Additionally, Arg386 may be involved in substrate recognition by the intrinsic tenase complex, providing a possible explanation for the differential effect on the two branches of the coagulation cascade. Recombinant FX mutant studies confirmed our findings in patient plasma and provided further support for these hypotheses.

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Alnsour, Hamza Mohammad Khaleel. "Role of the blood clot stabilization in early bone regeneration and osseointegration." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46960399.

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Background: Blood clot formation is one of the first events in bone regeneration and osseointegration. The blood clot adheres to dental implants with hydrophilic surfaces more favorably than to those with hydrophobic surfaces. This appears to result in better bone healing and bone fill of defects around dental implants. Objective: To assess the impact of blood clot stabilization at modSLA titanium implants on bone formation in chronic-type defects in a dog model. Material & methods: Ten modSLA implants were installed in 5 dogs after creation of saddle-type buccal-lingual bony defects. In 5 implants (test sites), the blood clot was removed by sterile saline irrigation, while the clot was left undisturbed on the other 5 implants (control sites). After 8 weeks of healing, the animals were sacrificed and sections were prepared for histomorphometric analysis. The following measurements were performed: The residual defect length (DL), the buccal and lingual most coronal level of bone in contact with the implant (CBI-b and CPI-l), the new bone height (NBH), the percentage of bone to implant contact (BIC), the area of new bone fill (BF), the difference in buccal and lingual dimensions of CBI (D-CBI), and percentage of linear bone fill (PLF). Results: the mean values of DL were similar in both groups (3.4 mm). All parameters assessed were consistently more favorable in control sites: CBI-b: 1.3 vs. 1.5, CBI-l: 1.3 vs. 0.8, D-CBI: -0.2 vs -0.5, NBH: 1.9 mm vs. 2.1 mm, PLF: 57.1% vs. 64.5% and BF: 4.4 mm? vs. 6.0 mm?. However, these differences were not statistically significant. Conclusion: In the light of consistently more favorable parameters assessed for the healing of saddle-shaped bony defects around implants, it is assumed that a stabilized blood clot contributed to early bone regeneration and osseointegration. Undisturbed blood clot formation may, indeed, be a prerequisite for optimal treatment outcomes. However, owing to the small sample size in the present study, these tendencies ought to be explored in further studies. published_or_final_version Dental Surgery Master Master of Dental Surgery

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Bernewitz, Richard [Verfasser]. "Charakterisierung von Doppelemulsionen mittels NMR und CLSM - Struktur und Diffusion / Richard Bernewitz." München : Verlag Dr. Hut, 2013. http://d-nb.info/1045125628/34.

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Larsson, Joel, and BEICHEN CHEN. "Sales and Operations planning : Complexities in the S&OP/CLSC interface." Thesis, KTH, Industriell Management, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-165544.

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Environmental concerns are increasing in today's marketplace as well as the pressure for companies tobe as efficient as possible in order to retain and gain market share. This has led to a need forstandardized processes. A process that has become increasingly more common in companies is thesales and operations planning (S&OP) process which aims to match demand with supply. With theenvironmental concern growing in interest it is becoming more important for companies to reuse aproduct in order to utilize the remaining value of the product. This if often only done if there isfinancial gains from the commitment. This is done in a closed loop supply chain where OriginalEquipment Manufacturers (OEM) takes back and remanufacture, refurbish and repair used products.With a growing interest in closed loop supply chains it is becoming increasingly more important forcompanies to be efficient in this area as well. The focal company of this study is working with theirsales and operations planning process as well as with remanufactured products in order to becomemore efficient with their processes they want to integrate the remanufactured products, in this studycalled R2 products into the already existing S&OP process. The aim of this study was hence toinvestigate what complexities that may arise when remanufactured products are integrated into anS&OP process, i.e. what challenges that would occur when remanufactured products were brought into the S&OP process. The case design included semi-structured interviews as the main data source. The results of the studyshowed that complexities may arise in all five steps of the S&OP process. The main findings showedthat the biggest impact of integration would be in the first two stages of the five step process, havingthe most complexities. This study has both academic and managerial implications. In academia thestudy contributes with knowledge in an interface which at the time of this study has been paid verylittle attention in research. This study also provides researchers with a conceptual framework whichcan be tested in other settings and used as a basis for further evaluation of this interface. Themanagerial implications comes from having the possibility by this study to know potential areas thatwill need extra attention before an integration of remanufactured products is conducted. Theframework presented in this study can provide managers with a checklist to follow in the integrationprocess. Den miljömässiga medvetenheten på dagens marknader ökar och likaså trycket på företag att vara så effektiva som möjligt för att behålla och vinna markandsandelar. Detta har lett till att behov av att standardisera processer där en mer vanligt förekommande process är sälj- och verksamhetsledningsprocessen (Sales and Operations Planning) som har till uppgift att balansera utbud och efterfrågan. Med den ökande miljömässiga medvetenheten blir det mer och mer viktigt för företag att öka längden på produktens livscykel genom att ta tillvara på det resterande värdet när den initiala kunden nått sitt slut på användandet. Detta görs dock ofta endast om det även är lönsamt för företaget. Detta görs i en så kallad sluten försörjningskedja (closed loop supply chain) där originaltillverkare tar tillbaka produkter och omarbetar dem för att ge dem nytt liv. Med ökande intresse och globalt tryck om hållbarhet är även detta ett område där företag börjar sträva mot att bli mer effektiva. Fallföretaget i denna studie arbetar med sälj och verksamhetsledning, tillika med omarbetade produkter. För att blir att öka effektiviteten i deras processer vill de därför integrera deras omarbetade produkter i den befintliga sälj och verksamhetsledningsprocessen. I denna studie kallas dessa produkter för R2. Syftet med denna studie var således att undersöka vilka komplexiteter som kan uppkomma vid denna integrering. Det vill säga, vilka oväntade utmaningar som kan framkomma när R2 produkterna integreras i sälj och verksamhetsledningsprocessen. Fallstudiens utformning inkluderade semistrukturerade intervjuer som huvudsaklig datakälla. Resultaten av studien visade att komplexiteter kan uppkomma i alla fem delar av sälj- och verksamhetsledningsprocessen. De huvudsakliga resultaten visade dock att den största påverkan skulle hamna i de första två stegen av den fördefinierade femstegsprocessen. Denna studie har både akademiska och praktiska implikationer. För akademin bidrar studien med kunskap i gränssnittet mellan sälj- och verksamhetsledning och omarbetade produkter. Den bidrar också med ett konceptuellt ramverk som kan användas av forskare för att vidareutveckla och utvärdera gränssnittet. De praktiska implikationerna kommer från att denna studie ger möjlighet för beslutsfattare i företage att förstå potentiella områden som behöver extra uppmärksamhet före en integration av omarbetade produkter genomförs.

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Smith, Stephen Matthew. "Development of a technique for the prediction of clot localisation in vitro." Thesis, University of Sheffield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425215.

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Ho, Laura. "Altered clot formation and anticoagulation in a familial Alzheimer's disease mouse model." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45350.

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Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and the leading form of dementia. Its complex etiology is traditionally attributed to an increase in the production and aggregation of amyloid-beta (Aβ). However, vascular risk factors and related disorders are also associated with the development of AD. The mechanism by which these deficiencies lead to neurodegeneration remains unclear. An altered hemostatic state has increasingly been implicated in AD pathogenesis, with the majority of research focusing on the interaction between Aβ and fibrin. It was therefore of interest to assess previously uncharacterized components of coagulation and anticoagulation in a familial AD (FAD) mouse model. Clot formation was initially analyzed using platelet rich plasma, with aged AD mice exhibiting 40% shorter clotting times compared to age-matched controls. Thrombin generation revealed differences attributable to an altered clot integrity. AD mice may form clots composed of a dense network of thin fibrin strands, resistant to fibrinolysis. Correspondingly, antithrombin (AT) activity was also reduced. These changes were subject to age, occurring specifically in aged mice only. These data suggest a change in clot formation and integrity concomitant with the development of AD. The interaction between Aβ and AT was examined in vitro, with Aβ42 and Aβ40 decreasing AT activity in a concentration dependent manner. A clinical study evaluating prothrombotic markers revealed a trend towards lower AT activity in AD patients, though not statistically significant. The changes in clot formation and anticoagulation potentiating a prothrombotic state may be specific to the FAD mouse model, but may still contribute to the elucidation of AD pathogenesis.

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Cooke, Esther J. "Characterisation of cellular fibrinogen phosphorylation and its functional implications in clot formation." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/9035/.

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Fibrinogen is a vital component of coagulation; cleavage of fibrinogen yields fibrin monomers that polymerise to form a network of fibres, constituting the blood clot. Human fibrinogen is secreted from hepatocytes in its phosphorylated form, with 20-25 % of circulating fibrinogen phosphorylated exclusively at Aα chain Ser3 and Ser345. Phosphorylation of fibrinogen is elevated in acute phase conditions, venous thrombosis and ovarian cancer, but little is known about the regulation and effects of this modification. The aims of this PhD project were to characterise the cellular mechanism and functional role of fibrinogen phosphorylation in vivo. Human hepatoma cells were incubated in the presence and absence of IL-6 and the phosphate content of secreted fibrinogen was analysed by western blotting. Interleukin-6 caused a 3.1-fold increase in fibrinogen phosphorylation, demonstrating for the first time that the up-regulation of this modification in acute phase conditions is regulated at the cellular level. Using real-time PCR, IL-6 was found to significantly enhance (6.0-fold) the expression of Golgi casein kinase Fam20A, whose recognition sequence matches the Ser3 and Ser345 phosphorylation sites. Expression of other potential fibrinogen kinases, including CK2, Fam20B and Fam20C, were unchanged. This finding suggests that Fam20A plays an important role in the hepatocellular response to acute phase conditions and may phosphorylate fibrinogen in vivo. Chromatographic enrichment of phosphorylated human plasma fibrinogen was conducted for functional analyses. Binding and activity assays found no effect of fibrinogen phosphorylation on FXIII cross-linking of fibrin α and γ chains, plasmin(ogen) binding to fibrinogen, or α2-antiplasmin incorporation. Analysis by SDS-PAGE revealed a small decrease in the rate of fibrinogen degradation by plasmin with increasing phosphorylation, indicating a possible role in protection from fibrinolysis. Scanning electron microscopy and turbidimetric assays revealed thinner fibres and more extensive branching in clots with a higher phosphate content, which typically represents a pro-thrombotic structure. This work highlights the importance of fibrinogen phosphorylation in maintaining the balance between clot formation and lysis. Investigations have shown that increased intracellular kinase activity leads to elevated fibrinogen phosphorylation in acute phase conditions. The observed alterations to clot phenotype with elevated fibrinogen phosphorylation suggest this modification may help to stem bleeding following trauma. Furthermore, it may have important implications in the development of thrombosis, which would make it a valuable target for therapeutic intervention in associated pathologies.

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Rasheed, Mollah Mohammed Haroon Ar. "Communicative Language Teaching (CLT) in Bangladesh: Effectiveness and Enhancements." Thesis, University of Canterbury. School of Teacher Education, 2011. http://hdl.handle.net/10092/9450.

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This investigation reports on a study that explores the views of students, teachers and parents about the Communicative Language Teaching (CLT) approach in learning English as a second language in Bangladesh. This study focuses on the improvement of English language outcomes in Bangladesh. Though compulsory for fifteen years of schooling, public examination results indicate that students perform poorly in English. This research is conducted at the secondary schools in Bangladesh where English is compulsory because of its global nature as the second or foreign language. Mainstream students learning English using the Communicative Language Teaching (CLT) approach are facing many challenges. The study employs a mixed methods approach which includes qualitative interviews, semi-structured focus group interviews and observations; and quantitative data involved achievement tests to find gaps between oral and written attainment, in order to determine the effectiveness of CLT developing language skills to communicate in and outside the classrooms. ESL learners in Bangladesh have been using CLT for nearly two decades, but the attainments are not satisfactory particularly in oral language (listening and speaking) compared to written language (reading and writing). Four schools (two high and two low achievement) were selected from two divisional cities according to the public examination results. Five students, all English subject teachers and five parents from each school were invited randomly to participate. Findings indicated a confirmation of the gap between oral and written language achievements and highlighted that CLT is not working effectively to develop communicative competence to the learners. The participants identified several factors causing this. Among these were large class sizes (number of students), an extensive curriculum, insufficient class time (duration), an inappropriate examination system, excessive teacher workload, lack of parent awareness of CLT, and negative relationships between home and school. All of these factors impact on the effectiveness of CLT in Bangladesh. All participants agreed that CLT as an approach is better than other approaches used in Bangladesh to develop English language learning, but the varied interpretation and implementation (practice) makes it less effective. Therefore, they suggested some issues for local and national level policy makers that could enhance the CLT practice in Bangladesh.

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McAlister, Mark S. B. "Expression, characterisation and purification of complement Cls domain-1." Thesis, University of Aberdeen, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358182.

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The aim of this project was to develop an expression system and protein purification system to allow production of the N-terminal domain of complement Cls (Cls-I) for structural studies by NMR spectroscopy or X-ray crystallography, and possibly for functional studies. A yeast expression/secretion vector has been constructed by ligating PCR-isolated Cls-I to the yeast α-factor leader sequence and the yeast phosphoglycerate kinase expression cassette. Yeast cells transformed with the expression vector produced two bands on SDS-PAGE that differed by 1-2kDa in apparent molecular weight (14kDa and 12kDa). The 14kDa (a.Mr.) form of Cls-I was N-terminally intact and mass spectrometry indicated that it had the expected mass of C-terminally intact unmodified Cls-I. The 12kDa (a.Mr.) form of Cls-I was N-terminally recessed by two amino-acids, and mass spectrometry suggested that it was also C-terminally intact and not further post-translationally modified. Glycoprotein detection blotting suggested that Cls-I was not glycosylated and a dephosphorylation experiment suggested that Cls-I was not phosphorylated in agreement with the mass spectrometry results. The N-terminal cleavage of Cls-I appeared to be mediated by the STE13 encoded diaminopeptidase A, since 60% of Cls-I secreted from a ste13 partially deficient mutant strain (ER109-5C) was N-terminally intact, but only 25-40% of Cls-I secreted from the `wild-type' BJ1991 transformants was intact. SDS-PAGE of intracellular protein suggested that there was not a significant intracellular accumulation of Cls-I. As yeast transformant cultures entered late transition/stationary phase (O.D.600nm = 3.5-4.5) a C-terminal proteolytic cleavage of both 14kDa and 12kDa (a.Mr.) forms of Cls-I appeared to occur, resulting in the formation of doublets of both bands. This was avoided by harvesting the cultures at O.D.600nm = 3-3.5.

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Kjellgren, Linda, and Susanna Thurin. "Korslimmat Trä : En guide för byggande med CLT-stomme." Thesis, KTH, Byggteknik och design, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191452.

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Landskroner, Kyle Alan. "Thrombosis and Thrombolysis: Emphasis on Hemophilia and Effect of Clot Dissolution with Plasmin." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-08142005-145317/.

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The purpose of this research was to understand the mechanisms in which blood clots form and are degraded. The research studies examined the role of an endogenous protease, plasmin, which is found in all vertebrates, and the optimal doses of plasmin required to dissolve blood clots. When we investigated clot lysis with plasmin we examined blood clots from several species to which varying concentrations of plasmin were added, as well as varying methods of plasmin administration. The results of these studies not only highlighted important dose-response relationships of plasmin, but also demonstrated differences in the effect of human plasmin to dissolve blood clots compared to blood clot from the species tested. Porcine clots, in particular, were more resistant to lysis compared with human clots, while ovine clots had similar lysis compared with human clots. In addition, this research demonstrated that plasmin?s effectiveness to lyse thrombi increases with an increase in clot surface area, e.g, by fragmentation, or when plasmin is administered as an intrathrombic administration. In separate studies, to investigate clot formation, we uesd mice that lack the FVIII protein. For these experiments we investigated the formation of blood clot formation using rotational thromboelastography (ROTEG) that measures the formation of fibrin in whole blood. This method was shown to be extremely sensitive to low levels of factor VIII protein and may have applications to classify particular phenotypes of hemophilia patients, or as a research tool to evaluate novel FVIII molecules.

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Dean, A. A. "Analysis and correlation of igneous clast geochemistry and petrography from four Mesozoic conglomerates." Thesis, University of Canterbury. Geology, 1993. http://hdl.handle.net/10092/9341.

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The Torlesse terrane encompasses three-quarters of the emergent New Zealand micro-continent and much speculation has been made as to the likely source for the detritus of which it is composed. This research concentrates on an examination of the igneous (plutonic and volcanic) clasts from three Torlesse conglomerates, one from the Rakaia terrane of Triassic age, and two from the Pahau terrane, of Early Cretaceous age, to obtain a better understanding of the characteristics of this source terrane. The Early Cretaceous Ethelton conglomerate comprises predominantly metaluminous I-type and weakly peraluminous evolved I-type granitoids that relate mineralogically and geochemically to the rhyolitic and dacitic volcanic clasts present and are thought to represent one cogenetic suite derived by partial melting of a common igneous source. The Mount Saul conglomerate contains a predominance of volcanic clasts and a variety of granitoid types. Some volcanic clasts relate to the I-type, and evolved I-type granitoids present. A-type peralkaline to weakly peraluminous volcanic clasts geochemically display a subduction related signature, that reflects source characteristics. A-type magmatism indicates an event unassociated with represented intrusives, either related to anorogenic magmatism or to a change to extensional tectonism. The predominant granodiorite character and low K content of Lake Hill conglomerate S type granitoid clasts contrasts with that of the other conglomerates. The dacitic and rhyolitic volcanic clasts examined from Lake Hill exhibit distinctive minerals indicative of I-types and relate to the evolved I-type granitoid clasts also present. The middle Cretaceous conglomerate located on Pitt Island, Chatham Islands is also examined to provide a comparison to the Torlesse conglomerates and an insight into source characteristics prior to continental separation between New Zealand and West Antarctica. The Chatham Islands conglomerate contains a variety of granitoid and volcanic types that are petrographically and geochemically comparable with the Torlesse conglomerates. The granitoid clasts are predominantly leucosyenogranites and leucomonzogranites. The volcanic clasts are rhyolites and dacites. Geochemically I-type, S-type and highly evolved/A-types are identified. The clasts from all four conglomerates examined exhibit trace element characteristics indicative of subduction-related magmatism. The granite type and highly felsic nature of most clasts indicates intrusion and extrusion occurred along an active continental margin that had attained full crustal thickness. The mineralogy and geochemistry of conglomerate clasts compares favourably with numerous volcano-plutonic continental provinces around the Pacific margin that are believed to represent the former Gondwana margin.

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Greenhalgh, Katriona Amy. "Mechanistic studies on human fibrinogen polymorphisms that influence blood clot formation and lysis." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/6324/.

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The blood clot is composed of a mesh of fibrin fibres with cellular elements embedded in this network. The structure of the fibrin clot can determine predisposition to atherothrombotic conditions, as compact clots composed of thin fibres and small pores are associated with premature and more severe cardiovascular disease. Both genetic and environmental effects can cause qualitative and quantitative changes in procoagulant and anti-fibrinolytic proteins, altering fibrin clot formation, structure and lysis. Three hypothesese were tested in this work: Firstly, the BβArg448Lys fibrinogen variant affects clot structural and functional properties in T2DM patients. Secondly, α2-AP is the protein responsible for the differences in lysis of recombinant BβArg448Lys fibrinogen variants in the plasma environment. And lastly, I proposed the AαTrp334Cys/Asn335Tyr changes in the Birmingham II patient are responsible for her clinical presentation. Accordingly, the aims of this work were to identify any additional effect of BβArg448Lys on fibrin network in type 2 diabetes, study the mechanisms behind the effects of the BβArg448Lys mutation on fibrin clot structural and functional properties, and finally, investigate the effect of fibrinogen AαTrp334Cys/Asn335Tyr on clot structure and lysis and abnormal patient phenotype. Compact clots with resistance to fibrinolysis were detected in carriers of Bβ448Lys variant of fibrinogen with diabetes. A direct role of the polymorphism in the changes observed with plasma clots was identified, and this may add to an already increased level of vascular risk in women with diabetes. In a recombinant system, differences in lysis between BβArg448Lys variants were attributable to the interplay between porosity of the clot, the fibrin-α2-AP interaction and plasmin generation. Finally, we confirm the AαTrp334Cys/Asn335Tryr substitutions in the fibrinogen BII patient are responsible for a clinical presentation of bleeding and thrombosis, providing mechanistic explanations for this patient phenotype. In summary, I extensively investigated the interplay between the fibrinogen molecule, fibrin clot structure, fibrinolysis and the environment and made a number of novel observations. Data generated has shed light on the mechanisms of increased thrombosis risk in patients with compact clots made of thin fibres, through genetic or environmental influence, which in turn will help to develop effective treatment strategies to reduce ischemic events in high risk patients.

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Ghassab, Sasan. "Thromboelastographic Clot Parameters of Autologous Equine Blood Products Activated by Various Clotting Agents." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397432210.

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Curtis, Corinna Briony Anne. "Flow-related clot deposition around artificial heart valves and its analysis by ultrasound." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/13535.

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The principle objectives of this study were to investigate deposition around test objects of a more complex geometry than bodies of revolution, using ultrasound, whilst over coming some of the problems previously encountered with ultrasonic imaging. Development of a new deaeration system reduced the number of bubbles (which attenuate ultrasound) in the milk flow to a satisfactory level, subsequently improving the quality of the ultrasound images. Further changes included the selection of a new rennet due to the unavailability of the original rennet used in the milk studies. Several rennets were investigated basing the final selection upon the similarity in behaviour, of the new and the original rennets, in response to agitation. A new test chamber was designed which allowed ultrasonic observation of the progressive development of clot structures and rate of deposition around various test objects, namely monoleaflet mechanical heart valves and monoleaflet valve models, during steady flow. Deposition resulting from pulsatile flow was too thin to be detected by ultrasound. It was seen from ultrasonic and visual observation that deposition thickness in regions of highest shear was thinner than in lower shear regions. Several mechanisms of deposition structure development were observed ultrasonically during steady flow, including a previously unreported mechanism.

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Adhikari, Sailesh. "Assessment of Cross Laminated Timber Markets for Hardware Lumber." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/103013.

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The goal of this study was to assess the potential of using hardwood lumber in CLT manufacturing. The goal was achieved by addressing four specific objectives. The first objective was to collect CLT manufacturers' perspectives for using hardwood lumber in the current manufacturing setup. The second objective was to determine hardwood sawmills' current ability to produce structural grade lumber (SGHL) from low value logs as a product mix through a survey of hardwood lumber producers in the US. The third objective was to conduct a log yield study of SGHL production from yellow poplar (YP) logs to produce 6'' and 8'' width SGHL to match the PRG 320 requirements. The fourth objective was to determine CLTs' production cost using SGHL and compared it with the CLTs manufactured from southern yellow pine (SYP). The results suggest that all three CLT industries visited and interviewed had sufficient technology to produce hardwood CLTs. The production of hardwood CLTs was mainly limited by the quality and quantity of lumber available. The hardwood sawmill survey results indicated that, currently, less than 10% of the sawmills had all the resources required to produce SGHL. The current ability of the sawmills was measured based on the resources necessary to begin SGHL production. Forty percent of the sawmills would require an investment in sawing technology to saw SGHL, 70% would require employing a certified lumber grader, and 80% would require a planer to surface lumber. Another significant finding was the sawmills' willingness to collaborate with other sawmills and lumber manufacturers. More than 50% of sawmills were open to potential collaboration with other stakeholders if necessary, which is crucial to commercializing SGHL for a new market. The log yield study of yellow poplar helped demonstrate that the mixed grade lumber production method to convert lumber from lower quality zones as SGHL yields higher lumber volume for sawmills and at the same time reduces lower-grade lumber volume. On average, SGHL production increased lumber volume by more than 6% compared to only NHLA grade lumber production when 65% of the lumber was converted to SGHL. The volume of lower lumber grades from 2 common and below decreased from an average of 85% to less than 30% when producing SGHL as a product mix with NHLA grade lumber. This study observed more than 95% of SGHL as Number 3 and better lumber grades. At estimated lumber value, 2x6 and 2x8 SGHL and NHLA grade lumber production as product mix from a log generate higher revenue for all log groups except for the diameter 13" logs. A lower percentage of higher-grade lumber was observed for diameter 13’’ logs than other log groups from this experiment, which resulted in lower revenue. Production cost of CLTs was determined based on the lumber value to manufacture 40' x 10' plain panels with different combinations by lumber grade of yellow poplar and southern yellow pine lumber alone. Production cost was determined by assuming that lumber value contributes 40% of CLTs' total production cost. The 3- ply CLT panels were manufactured using S. Selects lumber in a major direction, and No 1-grade lumber in the minor direction from YP had a production cost of $662.56 per cubic meter, which cost only $643.10 when SYP lumber was used at referenced lumber value. This study concludes that CLT panels from YP cost 3-7 % more than SYP-CLTs at the referenced lumber values. Ph.D. This research aims to expand the hardwood lumber consumption in the US by evaluating the opportunity to manufacture cross-laminated timber (CLTs). First, CLT manufacturing industries were visited to know their current capacity to process hardwood lumber. The results suggest that all three CLT industries had sufficient technology to produce hardwood CLTs, and the production was mainly limited by the quality and quantity of lumber available. Commercially hardwood can be used in CLT manufacturing if it can be used for structural application. Hardwood lumber must meet the structural application's minimum requirements to manufacture the structural grade CLTs, so we surveyed the hardwood sawmills to know if they have the required resources to manufacture the structural grade hardwood lumber (SGHL). Only ten percent of the sawmills had required technology to produce SGHL without additional investments. Production of the SGHL also required to generate more revenue for the hardwood sawmills, so we conducted the log yield study to know how the revenue structure of sawmill operation will change from the mixed grade lumber production. At estimated lumber value, 2x6 and 2x8 SGHL and 1-inch National Hardwood Lumber Association (NHLA) grade lumber production as product mix from logs generate higher revenue for all log groups except for the diameter 13" logs. Finally, the production cost of SGHL from the log yield study was evaluated and used to produce CLTs at 40% production cost from lumber at 15% profit margins for sawmills and compare with southern yellow pines CLTs. The results indicate that yellow poplar CLTs cost 3-7 % more than southern yellow pines CLTs at the referenced lumber values. This study concludes that hardwood lumber can be used in CLT manufacturing, so there is an opportunity for hardwood sawmills to expand the market. The first step for commercial production of hardwood CLTs is to produce SGHL on a commercial scale, given that sawmills can benefit from these new products in the current lumber market and meet the minimum requirements of the CLT raw materials.

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Hasuni, Hesen Kathum, Khamis Adib Sekran Al-douri, and Mohammed Hussein Hamodi. "Compression Strength Perpendicular to Grain in Cross-laminated Timber (CLT)." Thesis, Växjö University, Växjö University, Växjö University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-5349.

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The compressive strength perpendicular to grain of cross laminated timber (CLT) was studied experimentally. The problem was also theoretically analyzed and a finite element model was created and solved using a commercial finite element software package. The experiments were carried out with three layer CLT specimens of dimensions 200x200x120 mm and 300x300x120 mm. In some of the experiments a contact free deformation measurement system was used to analyze the strain field during loading. Different ways to apply the load were used: over the whole surface of the specimens and by a 50 mm wide steel bar. The position of the steel bar in relation to the specimen edge and its orientation relative the surface grain direction was varied. It was found that the compression strength of the cross laminated timber depended on the way in which the load was applied. The compression strength perpendicular to grain was found vary from 2.9 N/mm2 for specimens loaded by a line load at the edge of the specimen and parallel to the surface grain direction to 5.8 N/mm2 for specimens loaded by a line load at the specimen centre and perpendicular to the surface fiber direction. Tryckhållfastheten vinkelrät fiberriktningen i korslimmade massivträskivor (CLT) bestämdes experimentellt. Även teoretiska studier genomfördes med hjälp av ett kommersiellt finita elementprogram. Provningarna genomfördes på treskiktsskivor med måtten 200x200x120 mm samt 300x300x120 mm. I vissa av försöken användes dessutom ett mätsystem för beröringsfri deformationsmätning för att bestämma töjningsfälten. Olika sätt att belasta provbitarna undersöktes: genom att belasta hela provytan eller genom att belasta provet med en 50 mm bred stålstav. Stålstavens läge i förhållande till provbitens kant och dess orientering i förhållande till ytskiktets fiberriktning varierades. De experimentella resultaten visade att hållfastheten beror på hur provbitarna belastas. Tryckhållfastheten varierade mellan 2.9 N/mm2 för fallet med en linjelast vid provbitens kant och orienterad parallellt med ytskiktets fiberriktning och 5.8 N/mm2 för fallet med en linjelast mitt på provbiten och orienterad vinkelrät mot ytskiktets fiberriktning.

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Leroux, Madeline. "Performance et optimisation énergétique d'un édifice à bureaux en CLT." Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/29012/29012.pdf.

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Svensson, Meulmann Sebastian, and Egzon Latifi. "Modelling and testing of CLT panels for evaluation of stiffness." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-104766.

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The use of timber in building structures is steadily increasing. cross laminated timber (CLT) is an engineered wood product made of an uneven number of layers of lamellas glued at an angle of 90 degrees to each other. This gives CLT high stiffness and strength to bending in all directions, and capability of taking load both in-plane and out-of-plane. Due to the large size of CLT elements, they allow for quick assembly of strong structures. Due to both economic and environmental reasons it is important for producers of CLT to optimize the use of the wood material by using the timber with higher stiffness and strength where it is most needed. This thesis is about evaluating the bending and shear stiffness of CLT elements, when used as plates, depending on the quality of wood used in the different layers. Four-point bending tests are carried out on elements of different compositions and a parametrized finite element model is created. Thus, the model is validated on the basis of experimental tests to evaluate the influence of different quality of different layers. The measured dynamic MoE proved to have good potential to be used as the longitudinal bending stiffness in an FE-model, with a deviation from the experimental tests of less than 1%. There is a strong correlation between the bending stiffness and bending strength of the plates. The effective rolling shear modulus in pine was calculated to be around 170 MPa for pine of dimension 40 x 195 mm2 . Grading the boards into two different classes used for different layers proved to increase the MoE of the plates by 11-17% for 3- and 5-layer CLT.

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Mestar, Mohammed. "Kinematic Behaviour of Cross Laminated Timber (CLT) Shearwalls with Openings." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40929.

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An integrated experimental and numerical research program investigating the elastic and inelastic performance as well as the kinematic behaviour of shearwalls with openings is presented in this study. The influence of the geometrical dimensions of the wall configurations and the mechanical properties and configurations of hold-downs on both elastic and inelastic behaviours including the possible kinematic modes of the shearwalls are investigated. The research also proposes the concept of equivalent-frame-model applicable for shearwalls where openings are cut-out from CLT panels. Are also presented, five racking tests performed on full scale CLT walls in order to validate the numerical models as well as the equivalent frame model. From review of the available literature emerges that for CLT shearwalls with openings, studies are not at the same level of abundance in research compared to walls without openings, due to the simple reason that SSW is generally a widespread technique. Thus, the kinematic behaviour and the coupling effect are inexistent and presented here. The investigations of the wall’s behaviour in the elastic and inelastic ranges demonstrate the important effect of the lintel and wall segment slenderness as well as the hold-down stiffness effect on the mechanical behaviour and the global kinematic behaviour as well. It is found that the kinematic modes can change when the walls are stressed beyond their elasticity limit. The failure mode and the global ductility are highly dependent on the hold-down configurations particularly for walls with door openings. The degree of coupling decrease with increased hold-down stiffness and the wall segment width. With regards to the equivalent frame model, a reasonable fit is found between the proposed EFM and a detailed 2D area element model when the global elastic stiffness and tensile load in the hold-down were compared. The model is successfully validated through five full-scale tests on CLT shearwalls with door or window opening as well as two published studies on walls with door openings. The EFM is capable of predicting the behaviour in the wall with reasonable accuracy, especially for walls whose behaviour was dominated by the hold-down behaviour.

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Alzahrani, Saad Hassan S. "Cardiometabolic risk factors, clot structure and the effects of therapies in individuals with diabetes." Thesis, University of Leeds, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540551.

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Huang, Yunjie. "ADP-RIBOSYLATION FACTOR 6 (ARF6) REGULATES INTEGRIN αIIbβ3 TRAFFICKING, PLATELET SPREADING, AND CLOT RETRACTION". UKnowledge, 2015. http://uknowledge.uky.edu/biochem_etds/20.

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Endocytic trafficking of platelet surface receptors plays a role in the accumulation of granule cargo (i.e. fibrinogen and VEGF) and thus could contribute to hemostasis, angiogenesis, or inflammation. However, the mechanisms of platelet endocytosis are poorly understood. The small GTP-binding protein, ADP-ribosylation factor 6 (Arf6), regulates integrin trafficking in nucleated cells; therefore, we posited that Arf6 functions similarly in platelets. To address this, we generated platelet-specific, Arf6 knockout mice. Arf6-/- platelets had a storage defect for fibrinogen but not other cargo, implying Arf6’s role in integrin αIIbβ3 trafficking. Additionally, platelets from Arf6-/- mice injected with biotinylated-fibrinogen, showed lower accumulation of the modified protein than did WT mice. Resting and activated αIIbβ3 levels, measured by FACS, were unchanged in Arf6-/- platelets. Arf6-/- platelets had normal agonist-induced aggregation and ATP release; however, they showed faster clot retraction and enhanced spreading, which appears due to altered αIIbβ3 trafficking since myosin light chain phosphorylation and Rac1 activation, in response to thrombin, were unaffected. Arf6-/- mice showed no hemostasis defect in tail-bleeding or FeCl3–induced carotid injury assays. These data suggest a role for Arf6 in integrin αIIbβ3 trafficking in platelets. Additionally, the regulation of Arf6 in platelets was also investigated, focusing on integrin αIIbβ3 outside-in signaling which was suggested to be responsible for the second wave of Arf6-GTP loss. G protein-coupled receptor kinase-interacting protein 1 (GIT1), a GTPase-activating protein (GAP) toward Arf6, is suggested to be involved in αIIbβ3 downstream signaling. I found that GIT1, complex with β-PIX, was translocated to the detergent-insoluble pellet upon human platelet activation, a process that is blocked by RGDS and myrArf6 peptide treatment. Moreover, tyrosine-phosphorylation of GIT1 was impaired by treatment with both peptides or with actin polymerization inhibitors. GIT1’s role in platelets was further studied using platelet-specific, GIT1 knockout mice. GIT1-/- platelets failed to show any defect, including clot retraction or fibrinogen storage. Unlike human platelets, GIT1 expression levels were much lower in mouse platelets, suggesting that GIT2 may be the functionally relevant Arf6-GAP in mouse platelets. The data in this dissertation identify that Arf6 mediates fibrinogen storage, implying its role in integrin αIIbβ3 trafficking in platelets.

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Tao, Yegang. "Distortion-constraint compression of three-dimensional CLSM images using image pyramid and vector quantization." Thesis, University of Glasgow, 2005. http://theses.gla.ac.uk/4926/.

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The confocal microscopy imaging techniques, which allow optical sectioning, have been successfully exploited in biomedical studies. Biomedical scientists can benefit from more realistic visualization and much more accurate diagnosis by processing and analysing on a three-dimensional image data. The lack of efficient image compression standards makes such large volumetric image data slow to transfer over limited bandwidth networks. It also imposes large storage space requirements and high cost in archiving and maintenance. Conventional two-dimensional image coders do not take into account inter-frame correlations in three-dimensional image data. The standard multi-frame coders, like video coders, although they have good performance in capturing motion information, are not efficiently designed for coding multiple frames representing a stack of optical planes of a real object. Therefore a real three-dimensional image compression approach should be investigated. Moreover the reconstructed image quality is a very important concern in compressing medical images, because it could be directly related to the diagnosis accuracy. Most of the state-of-the-arts methods are based on transform coding, for instance JPEG is based on discrete-cosine-transform CDCT) and JPEG2000 is based on discrete- wavelet-transform (DWT). However in DCT and DWT methods, the control of the reconstructed image quality is inconvenient, involving considerable costs in computation, since they are fundamentally rate-parameterized methods rather than distortion-parameterized methods. Therefore it is very desirable to develop a transform-based distortion-parameterized compression method, which is expected to have high coding performance and also able to conveniently and accurately control the final distortion according to the user specified quality requirement. This thesis describes our work in developing a distortion-constraint three-dimensional image compression approach, using vector quantization techniques combined with image pyramid structures. We are expecting our method to have: 1. High coding performance in compressing three-dimensional microscopic image data, compared to the state-of-the-art three-dimensional image coders and other standardized two-dimensional image coders and video coders. 2. Distortion-control capability, which is a very desirable feature in medical 2. Distortion-control capability, which is a very desirable feature in medical image compression applications, is superior to the rate-parameterized methods in achieving a user specified quality requirement. The result is a three-dimensional image compression method, which has outstanding compression performance, measured objectively, for volumetric microscopic images. The distortion-constraint feature, by which users can expect to achieve a target image quality rather than the compressed file size, offers more flexible control of the reconstructed image quality than its rate-constraint counterparts in medical image applications. Additionally, it effectively reduces the artifacts presented in other approaches at low bit rates and also attenuates noise in the pre-compressed images. Furthermore, its advantages in progressive transmission and fast decoding make it suitable for bandwidth limited tele-communications and web-based image browsing applications.

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Jalal, Mohammed Mansour. "Statins exert antithrombotic action on platelet function and modulate clot formation structure and stability." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=235575.

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Statins are 3-hydroxy, 3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, which block the cholesterol biosynthetic pathway to lower total serum levels and LDL-cholesterol. The cholesterol pathway also provides a supply of isoprenoids (farnesyl and geranylgeranyl) for the prenylation of signaling molecules, which include the families of Ras and Rho small GTPases. Prenyl groups provide a membrane anchor that is essential for the correct membrane localisation and function of these proteins. Statins deplete cells of lipid geranylgeranyl diphosphate (GGPP) thereby inhibiting progression of the mevalonate pathway and prenylation of proteins. Two such proteins are Rab27b and Rap1, small GTPase proteins that are involved in the secretion of platelet granule and integrin activation. We hypothesise that statins can impair prenylation of Rab27b and Rap1a in platelets and thereby attenuate platelet function. The specific aims of the project were to analyse the impact of statins on the prenylation status of Rab27b and Rap1a in platelets. As Rab27b and Rap1a are known to be involved in secretion of platelet granules a secondary aim was to analyse the downstream effects of statins on this process following activation. Finally, we assessed the impact of treatment of platelets with statins on thrombus formation, stability and resistance to fibrinolysis. Platelets incubated with statins overnight were separated into cytosolic (aqueous) and membrane (detergent) components and visualised by Western blot. An accumulation of Rab27b and Rap1a was observed in the cytosolic compartments of statins treated platelets compared to untreated platelets, thus indicating indirect evidence that statins attenuate prenylation of Rab27b and Rap1a in platelets. The most effective statin in attenuating prenylation of Rab27b and Rap1a was atorvastatin (ATV). The inhibitory effect of statins on prenylation was recovered by GGPP, indicating that the mechanism of inhibition involved the mevalonate pathway. Release of ADP from platelet dense granules was significantly impeded following overnight treatment with ATV. In line with the inhibition of prenylation of Rab27b and Rap1a by ATV, addition of GGPP rescued the release of ADP from platelet dense granules. This suggests that attenuation of dense granules release by ATV occurs via interference in the mevalonate pathway and the inhibition of Rab27b prenylation. Furthermore, ATV significantly attenuates α-granules release in thrombin stimulated platelets, which was visualised as impaired accumulation of endogenous P-selectin, PAI-1 and fibrinogen on the activated membrane. Changes in the activation of α₁₁bβ₃ integrin on the stimulated platelet surface, observed as defective binding of exogenous fibrinogen and PAC-1, were also evident following treatment of platelets with ATV. In addition, ATV treatment of platelets reduced binding of CD41a, indicating that the copy number and activation of α₁₁bβ₃ integrin on stimulated platelets was significantly reduced. Statins were also found to significantly inhibit thrombin-induced platelet aggregation following incubation of platelets overnight with therapeutic concentrations of statins. Surprisingly GGPP did not rescue platelet aggregation indicating that different mechanisms are involved in inhibition of platelet responses by statins. Incubation of whole blood with ATV overnight significantly altered several haemostatic parameters. Using thromboelastography we demonstrated a delay in the coagulation time and clot formation time. Maximum clot firmness was also significantly reduced in the presence of statins compared to the control. The effect on clot firmness generally arises from platelet dysfunction and/or a change in fibrinogen concentration and function; the latter was ruled out using a Fibtem test, which shows no difference between treated and untreated whole blood. Similarly, formation of platelet-rich plasma clots was significantly delayed following pre-treatment with ATV overnight. These clots also exhibited lower maximal absorbances, which could represent differences in the fibrin network structure. In line with the reduction in fibrinogen binding defective clot retraction was also observed in platelet-rich plasma pre-treated with ATV overnight. Similar clot retraction results were observed with tirofiban and CytoD, suggesting that the inhibitory effect of ATV may involve modulation of α₁₁bβ₃ integrin activation. Platelet-rich plasma clots formed post-treatment with statins were visualised by confocal microscopy and revealed significant alterations in clot structure; observed as thinner fibrin fibres and fewer platelet aggregates. Additionally, we demonstrated that statins modulate clot stability and shorten time to lysis. Clots formed from platelet rich plasma that was subjected to incubation with ATV overnight revealed faster lysis by tPA compared to the absence of statin. These findings are also in agreement with the lysis of Chandler model thrombi formed from overnight incubated whole blood with ATV, which demonstrated faster lysis rate mediated by tPA. Furthermore, statins were shown to change the clot thrombodynamics as assessed by HemaCore analyser, which shows that stains implicate both clot growth in response to TF-coated comb and spontaneous clot lysis by tPA. In conclusion, statins directly inhibit Rab27b and Rap1a prenylation in platelets and down-regulated dense granules release. Inhibition of Rab27b and Rap1a prenylation, and dense granules release was recovered by GGPP, indicating that these effects are mediated through the mevalonate pathway. Impairment of platelet aggregation by statins resulted via multiple mechanisms as GGPP did not recovered the inhibition of aggregation by ATV. Statins also modulate fibrinogen binding, α-granules release, clot retraction and clot formation and stability in vitro. Together these results suggest that statins may directly attenuate the platelet response in vivo. The pleotropic effect of statins on platelets may contribute to the protective function of these class of drugs in cardiovascular diseases.

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Cham, Patricia. "Évalutation du programme d'habiletés parentales "Ensemble pour le mieux" offert au CLSC de Hull." Thèse, Université du Québec à Trois-Rivières, 2010. http://depot-e.uqtr.ca/1460/1/030145982.pdf.

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Vagnini, Francesco. "Vibro-acoustic characterization of CLT plates: analytical model and experimental measurement." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/15095/.

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Negli ultimi anni, la tecnica costruttiva a pannelli CLT ha riscosso un notevole successo, grazie a costi contenuti, velocità di messa in opera ed alta efficienza energetica con spessori moderati. Proprio per la grande resistenza meccanica i pannelli CLT vengono usati con spessori non eccessivi e quindi relativamente poca massa, per cui risulta critico l’isolamento acustico. Il lavoro di tesi pertanto riguarda lo studio e l’applicazione di metodi numerici e sperimentali per la valutazione del comportamento acustico di pannelli da costruzione in CLT. Si introduce un parametro fondamentale per la descrizione del campo acustico: l'efficienza di radiazione. Questo parametro descrive il rapporto che sussiste fra il suono irradiato e la velocità di vibrazione della lastra, coniugando cioè l’aspetto acustico e quello meccanico. Per la valutazione del parametro non esiste ancora una procedura standardizzata. Si è fatto quindi riferimento a diverse procedure tratte dalla letteratura scientifica in modo da poter comparare i risultati ottenuti. Sono stati applicati il Discrete Calculation Method (DCM) e la proposta di protocollo sperimentale del CSTB. È stata inoltre studiata la curva di dispersione della lastra. La determinazione sperimentale di tale curva risulta importante per poter dare un’ulteriore validazione ai risultati ottenuti con le misure di efficienza di radiazione ed in tal modo completare lo studio del comportamento vibro-acustico di lastre in CLT. I risultati ottenuti con i diversi metodi mostrano una buona compatibilità sia per il calcolo dell'efficienza di radiazione che per la valutazione della curva di dispersione.

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Beaudry, Jean-Pierre. "Le partage des tâches entre les aidantes naturelles et les services à domicile des CLSC." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0021/MQ46696.pdf.

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Dissertationen zum Thema „CLST“

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