<p>Mast cells (MCs) are forceful multifunctional effector cells of the immune system. MCs are normally distributed throughout connective and mucosal tissues, but in several pathological conditions accumulation of MCs occur. This accumulation is probable due to directed migration of MCs and they are subjects for migration at least two different occations: 1) when they are recruited as progenitor cells from the blood into the tissue; and 2) when they as mature MCs are recruited to sites of inflammation. The aim of this study was to investigate MC migration to chemoattractants released <i>in vivo</i> or <i>in vitro</i> (body fluids collected from patients with asthma or rheumatoid arthritis and T_H1- and T_H2-cytokines) and to recombinant cytokines (transforming growth factor -β (TGF-β) and CCL5/RANTES).</p><p>This thesis shows that bronchoalveolar lavage (BAL) fluid from asthmatic patients and synovial fluid from patients with rheumatiod arthritis contain MC chemoattractants, and that part of the chemotactic activity can be related to the presence of stem cell factor (SCF) and TGF-β. We also show that MC chemotactic activity during pollen season is significantly increased compared to before pollen season. Furthermore, we demonstrate that TGF-β isoforms, CCL5, TNF-α and IL-4 act as MC chemoattractants in a bellshaped dose- dependent manner. TGF-β proved to be an extremely potent attractant giving an optimal migratory response at 40fM and TGF-β3 being the most effective isoform. The chemokine CCL5 induced migration through interaction with the receptors CCR1 and CCR4 expressed on MC. Furthermore, we also found that TNF-α produced by T_H1-lymphocytes and IL-4 produced by T_H2-lymphocytes are MC chemoattractants.</p><p>In conclusion, with this thesis we have identified six new human mast cell chemoattractants and provide evidence that BAL fluid and synovial fluid from patients with asthma and rheumatoid arthritis, respectivly, contain MC chemoattractants. This information provides important clues in understanding the mechanisms behind MC recruitment to sites of inflammation.</p>

Mast cells (MCs) are forceful multifunctional effector cells of the immune system. MCs are normally distributed throughout connective and mucosal tissues, but in several pathological conditions accumulation of MCs occur. This accumulation is probable due to directed migration of MCs and they are subjects for migration at least two different occations: 1) when they are recruited as progenitor cells from the blood into the tissue; and 2) when they as mature MCs are recruited to sites of inflammation. The aim of this study was to investigate MC migration to chemoattractants released in vivo or in vitro (body fluids collected from patients with asthma or rheumatoid arthritis and TH1- and TH2-cytokines) and to recombinant cytokines (transforming growth factor -β (TGF-β) and CCL5/RANTES). This thesis shows that bronchoalveolar lavage (BAL) fluid from asthmatic patients and synovial fluid from patients with rheumatiod arthritis contain MC chemoattractants, and that part of the chemotactic activity can be related to the presence of stem cell factor (SCF) and TGF-β. We also show that MC chemotactic activity during pollen season is significantly increased compared to before pollen season. Furthermore, we demonstrate that TGF-β isoforms, CCL5, TNF-α and IL-4 act as MC chemoattractants in a bellshaped dose- dependent manner. TGF-β proved to be an extremely potent attractant giving an optimal migratory response at 40fM and TGF-β3 being the most effective isoform. The chemokine CCL5 induced migration through interaction with the receptors CCR1 and CCR4 expressed on MC. Furthermore, we also found that TNF-α produced by TH1-lymphocytes and IL-4 produced by TH2-lymphocytes are MC chemoattractants. In conclusion, with this thesis we have identified six new human mast cell chemoattractants and provide evidence that BAL fluid and synovial fluid from patients with asthma and rheumatoid arthritis, respectivly, contain MC chemoattractants. This information provides important clues in understanding the mechanisms behind MC recruitment to sites of inflammation.

An experimental wind tunnel study on the dynamic response of a 300 m tall guyed telecommunication mast under various wind loads was undertaken at the Boundary Layer Wind Tunnel Laboratory (BLWTL) in the University of Western Ontario, London, Canada. Although the dynamic response of guyed masts subjected to turbulent wind loads has been routinely analyzed using a number of numerical models, typically in the frequency domain, limited experimental verification of the dynamic analysis results has been performed. Full-scale measurements, where available, have proven to be difficult to correlate with analytical models due to the tremendous uncertainty inherent in field measurements. As a result, the need for systematic validation of existing analytical models remains.<p>In this investigation, a representative 300 m tall guyed telecommunication mast has been designed and modeled to an appropriate scale. Based on Canadian Standard CSA S37-01, and an empirical study on 41 existing guyed masts, the 300 m tall guyed mast was designed using wind load conforming to representative Canadian climate data obtained from National Building Code of Canada (NBCC 1995). Appropriate properties for the dynamically scaled full aeroelastic model were derived from the 300 m tall prototype guyed mast, which was intended to represent a realistic guyed mast for broadcasting applications in Canada.<p>The wind tunnel test of the guyed mast model was carried out in both open country and over water exposures, simulating medium and low turbulence flow conditions, respectively. Dynamic response characteristics measured during the wind tunnel tests have been analysed and summarized, including dynamic displacements, bending moments, response spectra and peak factors, as well as natural frequencies, mode shapes and structural damping. Comparisons have been made with predictions obtained from an existing frequency domain analysis model. <p>The wind tunnel test results show that good agreement was generally achieved between the frequency domain analytical model and the wind tunnel model with respect to both the magnitude and distribution of the monitored responses. It was found that measured dynamic bending moments were distributed in a fairly uniform manner over the mast height, and that mean (static) bending moments exhibit large variations, along with near-zero response zones at points of contraflexure. It was also found that nonlinear damping effects, associated with vibrations of the highly slackened leeward guys on the upper levels of the mast, may be beneficial in reducing dynamic mast displacements. <p>The spectrum studies indicated that lowest modes were dominated by large guy movements at top guy level and small mast movements, the middle modes were characterized by coupled effects between the guyed cables and mast, meanwhile the highest modes involved significant mast movements with little guy vibration. It is evident that the top of the mast displacement are dominated by the first and second modes.

This is a Bachelor degree project report describing the development process of a trapeze system for dinghy sailing. The project was performed in cooperation with Seldén Mast AB, manufacturer of spars and rigging systems for yachts and dinghies. The trapeze system is used in some dinghy sailing classes. It is used to move the weight of the crew outside of the boat to compensate the force created by the wind in the sails. The system consists of a number of components. Focus of the project was set on the position adjustment device and the attachment to the harness. The product development process included a pre study, a Product Design Specification, a function analysis, concept development, embodiment, and detail design. The project resulted in three products: two variants of trapeze cleats (adjustment devices) and a trapeze ring (to enable attachment to the harness).

An experimental wind tunnel study on the dynamic response of a 300 m tall guyed telecommunication mast under various wind loads was undertaken at the Boundary Layer Wind Tunnel Laboratory (BLWTL) in the University of Western Ontario, London, Canada. Although the dynamic response of guyed masts subjected to turbulent wind loads has been routinely analyzed using a number of numerical models, typically in the frequency domain, limited experimental verification of the dynamic analysis results has been performed. Full-scale measurements, where available, have proven to be difficult to correlate with analytical models due to the tremendous uncertainty inherent in field measurements. As a result, the need for systematic validation of existing analytical models remains.<p>In this investigation, a representative 300 m tall guyed telecommunication mast has been designed and modeled to an appropriate scale. Based on Canadian Standard CSA S37-01, and an empirical study on 41 existing guyed masts, the 300 m tall guyed mast was designed using wind load conforming to representative Canadian climate data obtained from National Building Code of Canada (NBCC 1995). Appropriate properties for the dynamically scaled full aeroelastic model were derived from the 300 m tall prototype guyed mast, which was intended to represent a realistic guyed mast for broadcasting applications in Canada.<p>The wind tunnel test of the guyed mast model was carried out in both open country and over water exposures, simulating medium and low turbulence flow conditions, respectively. Dynamic response characteristics measured during the wind tunnel tests have been analysed and summarized, including dynamic displacements, bending moments, response spectra and peak factors, as well as natural frequencies, mode shapes and structural damping. Comparisons have been made with predictions obtained from an existing frequency domain analysis model. <p>The wind tunnel test results show that good agreement was generally achieved between the frequency domain analytical model and the wind tunnel model with respect to both the magnitude and distribution of the monitored responses. It was found that measured dynamic bending moments were distributed in a fairly uniform manner over the mast height, and that mean (static) bending moments exhibit large variations, along with near-zero response zones at points of contraflexure. It was also found that nonlinear damping effects, associated with vibrations of the highly slackened leeward guys on the upper levels of the mast, may be beneficial in reducing dynamic mast displacements. <p>The spectrum studies indicated that lowest modes were dominated by large guy movements at top guy level and small mast movements, the middle modes were characterized by coupled effects between the guyed cables and mast, meanwhile the highest modes involved significant mast movements with little guy vibration. It is evident that the top of the mast displacement are dominated by the first and second modes.

[First published online] 2010-11-22 / 名古屋大学博士学位論文 学位の種類 : 博士(医学)(課程) 学位授与年月日:平成23年3月25日 澤井晶穂氏の博士論文として提出された

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 287-292). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 287-292). Also available on the Internet.

High mast illumination poles (HMIPs) are tall cantilevered structures used to efficiently illuminate large portions of highways and interchanges. Great interest in the performance of HMIPS has arisen from the discovery of extensive premature cracking at the toes of base plate to pole shaft welds of poles currently in service. These cracks, in some cases, have become so severe that HMIPs have actually collapsed, and therefore present a great threat to public safety. Previous research at the University of Texas at Austin sought to solve the design problems posed by these pole failures by conducting both full-scale and analytical tests on optimized designs of HMIPs for fatigue loads. These studies indicated that using full penetration welds to connect 3" thick base plates to relatively thin shaft walls minimized warping of the base plate during fatigue loading, and maximized fatigue performance. Toward the end of these studies when researchers sought to test an uncoated optimized HMIP back-to-back against a galvanized HMIP of the same design and material, researchers discovered the galvanized specimen had cracked during the galvanizing process. This finding prompted an in-depth study to determine the cause of these cracks, and to determine if practices could be implemented to prevent crack formation. Initially, bend radius, chemistry, and shaft to base plate thickness studies were conducted to find how these parameters affect HMIPs during galvanizing. These parameters were found to play a minor role in the cracking of HMIPs relative to the thermal effects induced during the galvanizing process. Full-scale and analytical tests verified the impact of thermal straining within HMIPs during galvanizing. Instrumenting HMIPs and smaller HMIP stub sections with thermocouples and strain gages provided temperature and initial strain gradients resulting from exposure to the molten zinc bath. This data, as well as observations of cracks in the tested HMIP sections, aided the development of a finite element parametric study comparing HMIPs of the same 150' length and 80 mph design but varying shaft thicknesses. This research concludes that reducing the pole shaft diameter to thickness ratio reduces the likelihood of galvanizing crack formation. / text

This thesis is focused on neural stem cell (NSC) and glioma biology. I discuss how NSCs interact with extracellular matrix (ECM) proteins in the stem cell niche, and investigate the consequences of deregulated Platelet-derived growth factor (PDGF) signaling for embryonic NSCs in transgenic mice. Furthermore I present cell cultures of human glioblastoma multiforme (GBM) that models human disease, taking into account the heterogeneity of GBM. Finally, interactions between brain tumors and mast cells are studied using the glioma cultures. In paper I, the importance of NSC interactions with the ECM in the stem cell niche during development is discussed. Contacts between NSCs and the ECM in the subventricular zone (SVZ) are emerging as important regulatory mechanisms. We show that early postnatal neural stem and progenitor cells (NSPC) attach to collagen I, and that the adhesion is explained by higher expression of collagen receptor integrins compared to adult NSPC. Further, blood vessels in the SVZ express collagen I, indicating a possible functional relationship. Growth factors, e.g. PDGF, regulate NSC proliferation and differentiation. Aberrant activation of growth factor signaling pathways also plays a role in brain tumor formation. Paper II demonstrates that transgenic mice expressing PDGF-B at high levels in embryonic NSCs displayed mild neurological defects but no hyperplasia or brain tumors. This suggests that a high level of PDGF is not sufficient to induce brain tumors from NSCs without further mutations. Paper III presents a novel panel of human glioma stem cell (GSC) lines from GBM that display NSC markers in vitro and form secondary orthotopic tumors in vivo. GBM has recently been categorized in molecular subclasses and we demonstrate, for the first time, that these subclasses can be retained in vitro by stem cell culture conditions. We have thus generated models for research and drug development aiming at a focused treatment depending on GBM subtype. Interactions with the immune system are integral parts of tumorigenesis. Mast cells are found in glioma and in paper IV we demonstrate that the grade-dependent infiltration of mast cells is in part mediated by macrophage migration inhibitory factor and phosphorylation of STAT5.