京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19184号 / 工博第4061号 / 新制||工||1626(附属図書館) / 32176 / 京都大学大学院工学研究科マイクロエンジニアリング専攻 / (主査)教授 田畑 修, 教授 琵琶 志朗, 准教授 土屋 智由, 教授 松原 厚 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

No description available.

Hereditary Equine Regional Derma Asthenia (HERDA) is a painful disfiguring autosomal recessive skin disorder of Quarter Horse lineages. Affected horses cannot be ridden and most are humanely destroyed. Five years following homozygosity mapping of a putative causal mutation responsible for HERDA, it remains unclear how this mutation causes the HERDA syndrome. HERDA horses have a missense mutation in peptidyl-prolyl cis-trans isomerase B (PPIB) which encodes cyclophilin B (CYPB) and alters folding and post-translational modifications of fibrillar collagen. Loss of function mutations in CYPB recognized in other species classically present as the debilitating bone disease, severe to lethal osteogenesis imperfect (OI). Objectives of this study were to develop a novel method for cryogenic clamping of tendons and ligaments of high tensile strength and validate its performance by ultimate tensile strength testing of normal equine deep digital flexor tendon. This validated method was then used to compare tendon and ligament of HERDA vs. control horses along with great vessels and skin. We hypothesized that all tissues of high fibrillar collagen content would have altered tensile properties due to the CYPB mutation affecting fibrous connective tissue globally within HERDA horses. Based on previous studies in our laboratory identifying reduced hydroxylysine content and altered collagen crosslink ratios in the skin of HERDA affected animals that implicate lysyl hydroxylase-1 (LH1) dysfunction, we hypothesized that the HERDA PPIB mutation modified an interaction between CYPB and LH1, interfering with hydroxylysine synthesis and its availability for collagen crosslink formation. In addition, we hypothesized that mutant CYPB may also lead to modifications of other known CYPB protein complexes, such as the CYPB, prolyl-3 hydroxylase-1 (P3H1) and cartilage associated protein (CRTAP) triplex. Goals of this study were to investigate the tensile properties of tissues with high fibrillar collagen content from HERDA homozygotes, to elucidate the mechanistic relationship of the HERDA CYPB mutation to the clinical disease, and to provide evidence to substantiate a heterozygote phenotype in HERDA which could be useful to explaining the correlation between lineages that carry the HERDA allele and performance outcomes in the discipline of western cutting competition.

The effect of xylan from different plant species on tensile properties of spruce pulp was studied. Xylans from spruce, birch, wheat straw and rice husks were mixed with the fresh white liquor and added at the later stages of separate kraft cooks, in exchange of the black liquor removed from the system at that time. Results show that xylans, from rice husk, wheat straw and birch, gave stronger pulps. However it was only possible to attach small quantities of xylans onto the fibers. Moreover, pulps containing birch and rice xylan were easier to beat than the other pulps in the study.

Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this study was to investigate the effect of nano ceramic fiber fillers on the physical properties of VST-50HD silicone maxillofacial prosthesis. Nano alumina fibers at 2 percent, 4-percent, and 6-percent wt were mixed into the VST-50HD silicone elastomer (Factor II Inc., Lakeside, AZ), a commercially-available poly(dimethylsiloxanes). Ten dumb-bell-shaped specimens were used to determine the tensile strength according to ISO 37:2005 and elongation at fracture. Ten trouser-shaped test pieces were used to determine the tear resistance according to ISO 34-1:2004. Shore A test method was used to measure the hardness of the material. The data collected from all quantitative studies of the modified silicones were analyzed using one-way ANOVA with concentration of nano ceramic fiber as the main variable. Specimens from VST- 50HD were also made and tested as control. Results: The mean values for tensile strength (MPa) of control group, 2-percent, 4-percent, and 6-percent reinforced nano ceramic fiber fillers were from 3.43 ± 0.12 to 5.48 ± 0.71. Tear strength (MPa) were from 2.34 ± 0.37 to 5.01 ± 0.39. Elongations at fracture were from 699.66 ± 43.69 to 793.51 ± 57.27. Shore A hardness were from 25.76 ± 2.18 to 38.76 ± 1.83. Conclusion: There was a significant difference (p < 0.001) in the mean tensile, tear and Shore A hardness strengths between the control group and 2-percent, 4-percent, and 6-percent percent reinforced nano ceramic fiber fillers; however, there was not a significant difference (p > 0.05) between 2-percent, 4-percent, and 6-percent reinforced nano ceramic fiber fillers. There was a significant difference (p < 0.001) in the mean elongation at fracture between the 2-percent and control group, 4-percent, and 6-percent reinforced nano ceramic fiber fillers; however, there was not a significant difference (p > 0.05) between control group, 4-percent, and 6-percent reinforced nano ceramic fiber fillers. The properties of the experiment were all lower than the control. Further research is needed to determine the appropriate material and amount of dispersing agent, coupling agent, and determination of the hydprophilicity of the nano ceramic fiber fillers with great emphasis on the dispersing agent.

Indiana University-Purdue University Indianapolis (IUPUI) / MICROTENSILE BOND STRENGTH OF NEW PASTE/PASTE RESIN-MODIFIED GLASS IONOMER CEMENT SYSTEMS: THE EFFECT OF DENTIN PRETREATMENT by Yasser Fawaz Al-fawaz Indiana University School of Dentistry Indianapolis, Indiana Background: In order to improve the clinical performance of RMGIC 3M ESPE and GC America introduced paste/paste resin-modified glass ionomer cements, Ketac™ Nano and Fuji Filling™ LC, respectively. Both companies developed non-rinse substrate conditioners (i.e., Ketac Nano Primer-3M ESPE and GC Self-Conditioner-GC America) that should be used with these new materials instead of the conventional polyacrylic acid. It has been also advised by both manufacturer’s to use this novel substrate conditioner with the previously marketed RMGICs. Objective: to investigate whether the use of novel non-rinse conditioners (i.e., Ketac Nano Primer 3M ESPE and GC Self Conditioner GC America) as substrate pre-treatment and the new paste/paste resin-modified glass-ionomer cement, RMGIC (Ketac™ Nano 3M ESPE and Fuji Filling™ LC GC America) would affect the microtensile dentin bond strength (µTBS) of the material when compared to the traditional RMGIC with polyacrylic acid as a surface substrate pre-treatment. Materials and Methods: 96 extracted non-restored human molar were sectioned to expose occlusal dentin. Dentin surface was finished with SiC paper to standardize the smear layer. Bonding protocols of the different materials to dentin were performed following the use of two dentin conditioners. Eight groups (n=12) were tested: G1: Ketac Nano Primer + Ketac Nano, G2: Ketac Conditioner + Ketac Nano, G3: Ketac Nano Primer + Photac Fil, G4: Ketac Conditioner + Photac Fil, G5: GC Self Conditioner + Fuji Filling LC, G6: GC Cavity Conditioner + Fuji Filling LC, G7: GC Self Conditioner + Fuji II LC and G8: GC Cavity Conditioner + Fuji II LC. The specimens were stored in 37°C for 24h in 100% humidity before cutting non-trimmed beams for the µTBS with cross-sectional areas of approximately 0.8 × 0.8 mm2. Nine beams were used from each specimen. Test was done using universal testing machine at a cross-head speed of 1mm/min. Debonded specimens were examined under a stereomicroscope at 45× magnification to evaluate the failure mode. Eight randomly chosen representative debonded beams were imaged under a scanning electron microscope (SEM). Results: µTBS in MPa (mean ± SE) were: G1: 9.5±1.0, G2: 11.0±1.0, G3:20.0±1.0, G4:16.8±0.9, G5: 15.1±1.0, G6: pre-test failure, G7: 20.0±1.0, G8:14.1±0.9. Weibull-distribution survival analysis was used to compare the differences in microtensile peak stress among the groups. Group5 has cohesive predominant faultier mod while the other groups have adhesive predominant failure. Conclusion: Within the limitations of this study, the use of the novel non-rinse conditioners did not improve the microtensile bond strength of new paste/paste RMGIC to dentin. In fact, the use of the novel non-rinse conditioners enhanced the bond strength of the traditional RMGIC to dentin.

No description available.

No description available.

Fibrinogen concentrates are used widely as a sealant during and after surgery to reduce blood loss. Commercially available fibrin sealants are made from pooled human blood, which carries the risk of blood-borne diseases, and are expensive. These concerns have brought to focus the need for autologous fibrinogen concentrates. This need has been addressed by utilizing a unique approach in which fibrinogen is precipitated from plasma with protamine. The physical properties of fibrin sealant prepared from fibrinogen precipitated with protamine were evaluated. The optimal precipitation conditions included a plasma protamine concentration of 10 mg/mL at room temperature. Under these conditions 96% ± 4% of the fibrinogen present in the plasma was precipitated and 98% ± 0.9% of the precipitated fibrinogen was clottable. In addition, it was shown that almost 50% of the factor XIII in the plasma was also precipitated along with the fibrinogen. The tensile and adhesion strengths and kinetics of fibrin sealant prepared from protamine-fibrinogen concentrate were evaluated. Tensile strength and adhesion strength both increased with increasing fibrinogen concentration. Addition of calcium chloride significantly increased the tensile and adhesion strengths. The addition of aprotinin and ε-aminocaproic acid (used to inhibit natural fibrinolysis) to the fibrinogen concentrate was shown to have no effect on the mechanical properties of the sealant. Kinetic experiments showed that the clotting time decreased as the thrombin and fibrinogen concentrations were increased. A rat model with controlled renal incisions was employed to evaluate the hemostatic efficacy of the fibrin sealant made from the protamine-fibrinogen concentrate. The fibrin sealant significantly reduced the blood loss and bleeding time when compared with controls (no sealant, plasma, and a commercial product). The sealant also significantly reduced blood loss and bleeding time in rats that were anticoagulated with heparin. A mathematical model based on tensile strength and adhesion strength was developed to predict the bleeding time in the animal wound. Model predictions showed that the ability of the fibrin sealant to reduce bleeding time, and therefore blood loss, was limited by the adhesion strength.

In today’s paper and board production, quality control is made on a single cross direction (CD)sample from each tambour. As several different properties are analysed, only a limited number of measurement results are obtained for one property. Therefore, the measurement results might not be representative for the properties of the entire width of the tambour. The first objective of the project was to investigate variations of thickness, surface roughness and mechanical properties with a much higher resolution and number of measurements. The results of the measurement were compared with the routine quality control of the mill. The second objective of the project was to evaluate the influence of the wire shake unit in the centreply on the properties of the produced board. The measurements were performed on Iggesundpaperboard samples.The high-resolution measurements were performed using the STFI structural thicknessmeasurement device, an OptiTopo topography measurement device and a modified Autolinedevice at RISE Bioeconomy. The statistical evaluation of the results was performed in Matlab.Standard deviation, local variance and a frequency analysis were calculated for the thicknessmeasurements. Only standard deviation was considered for the topography data. For the mechanical properties, the distribution was evaluated using the Weibull distribution, since theresults had a single-sided distribution. In addition, the properties were analysed as a function of their location, for example to identify deterministic deviations in cross direction.The results of the first part of the project showed that the everyday control conducted in Iggesund is sufficient for most of the properties. Greatest difference was found at the edges ofthe samples, where Iggesund standard quality control does not detect a major variation inproperties, as no measurements are performed that close to the edge of the web. For example,at one edge, the high frequent measurements showed a significant drop in thickness which were not detected with the everyday quality control.In the second part of the project, the effect of a shake unit on the paper properties was evaluated. Here it was seen that the thickness variation were reduced, which also can be interpreted as an improvement of formation in the centre ply of the paperboard. As for thesurface roughness a slight improvement was found. Also for the mechanical properties, the shake unit appeared to improve the uniformity of the product / I dagens pappers-och kartongproduktion görs kvalitetskontroll på en enda tvärremsa (CD) från varje tambour. Eftersom flera olika egenskaper analyseras, erhålls endast ett begränsat antal mätresultat för en egenskap. Därför är informationen begränsad och kanske inte representativ för hela bredden av tambours egenskaper. Projektets första mål var att undersöka variationer i tjocklek, ytjämnhet och mekaniska egenskaper med mycket högre upplösning och antal mätningar. Resultaten av mätningen jämfördes med brukets rutinmässiga kvalitetskontroll.Det andra syftet med projektet var att utvärdera effekten av viraskaken på egenskaperna hos den producerade kartongen. Samtliga mätningar utfördes på kartongprover från IggesundsBruk.Mätningarna med hög upplösning utfördes med hjälp av en STFI-mätare för strukturtjocklek,en OptiTopo-enhet och en modifierad L&amp;W Autoline-enhet. Den statistiska utvärderingen avresultaten utfördes i Matlab. Standardavvikelse, lokal variation och en frekvensanalys beräknades för tjockleksmätningarna. Endast standardavvikelse utvärderades för ytråhetsdata.För de mekaniska egenskaperna utvärderades fördelningen med hjälp av Weibullfördelningen,eftersom resultaten visade ett ensidigt beteende. Dessutom analyserades egenskaperna som en funktion av deras placering, till exempel för att identifiera deterministiska avvikelser i tvärriktningen.Resultaten av projektets första del visade att den dagliga kontrollen i Iggesund är tillräcklig för de flesta egenskaperna. Den största skillnaden hittades vid provets kanter, där Iggesundsstandardkvalitetskontroll Missar stora variationer för vissa egenskaper, eftersom inga mätningar utförs i det området på produkten. Vid ena sidan av nätverket visade de högfrekventa mätningarna en betydande minskning av tjockleken.I den andra delen av projektet utvärderades effekten av en skakningsenhet på pappersegenskaperna. Här såg man att variansen i tjockleksmätningarna indikerar en förbättring av formationen i kartongens mittskikt. När det gäller ytråheten konstaterades en liten förbättring. För de mekaniska egenskaperna föreföll viraskaken förbättra produktenslikformighet.