京都大学 / 新制・課程博士 / 博士(理学) / 甲第23703号 / 理博第4793号 / 新制||理||1686(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 井岡 邦仁, 教授 萩野 浩一, 教授 田中 貴浩 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Flatness of wood composite panels, such as Laminated Veneer Lumber, is often difficult to control during the manufacturing process. Out-of-plane deformation, or warpage, of wood veneers caused by changes in moisture content affects the ability to press flat panels. To understand wood panel warpage, experimental methods are developed to create and measure moisture-induced deformation of wood veneers on five species of various thicknesses. Three moisture induction methods are investigated and evaluated to determine the increase in moisture content. Experiments are developed to produce moisture gradients of two concentrations in the veneers to examine the effect on warpage behavior. Additionally, the surface area of applied moisture and veneer thickness is also investigated. Three-dimensional scanning technology is used to measure warpage of veneers. A procedure using a structured-light scanner is developed to analyze the surface curvatures to observe the effect of moisture-induced warpage. After moisture-induction treatment of the veneer, surface deformation data is measured using the scanner and the data is converted into a 3D solid body model that is used for curvature comb analysis. The results show that curvature comb analysis can be used to analyze the geometry of moisture-induce warpage. The method can be used to analyze the effect of moisture gradient variables on warpage behavior including concentration, veneer thickness, and surface area. The experimental methods developed can be used by future researchers to validate theoretical warpage prediction models. / Master of Science / Flatness of wood composite panels, such as Laminated Veneer Lumber, is often difficult to control during the manufacturing process. Warpage of wood veneers is caused by changes in moisture content affecting manufacturers' ability to press flat panels. To understand wood panel warpage, experimental methods are developed to create and measure moisture-induced warpage of wood veneers on five species of various thicknesses. Three moisture induction methods are investigated and evaluated to determine the increase in moisture content. Experiments are developed to produce moisture gradients of two concentrations in the veneers to examine the effect on warpage behavior. Additionally, the surface area of applied moisture and veneer thickness is also investigated. Three-dimensional scanning technology is used to measure warpage of veneers. A procedure is developed to analyze the surface curvatures to observe the effect of moisture-induced warpage. After moisture-induction treatment of the veneer, surface deformation data is measured and converted into a 3D solid body model that is used to analyze curvature. The results show that moisture induction methods used to induce warpage can experience different geometries to analyze a veneer's curvature. The methods can be used to analyze warpage behavior of veneers by future researchers to validate warpage prediction model.

Doctor of Philosophy / Department of Physics / Kristan L. Corwin / We have made significant accomplishments in the development of portable frequency standard inside hollow optical fibers. Such standards will improve portable optical frequency references available to the telecommunications industry. Our approach relies on the development of a stabilized Cr:forsterite laser to generate the frequency comb in the near-IR region. This laser is self referenced and locked to a CW laser which in turn is stabilized to a sub-Doppler feature of a molecular transition. The molecular transition is realized using a hollow core fiber filled with acetylene gas. We finally measured the absolute frequency of these molecular transitions to characterize the references. In this thesis, the major ideas, techniques and experimental results for the development and absolute frequency measurement of the portable frequency references are presented. A prism-based Cr:forsterite frequency comb is stabilized. We have effectively used the prism modulation along with power modulation inside the cavity in order to actively stabilize the frequency comb. We have also studied the carrier-envelope-offset frequency (f0) dynamics of the laser and its effect on laser stabilization. A reduction of f0 linewidth from [similar to]2 MHz to [similar to]20 kHz has also been observed. Both our in-loop and out-of-loop measurements of the comb stability showed that the comb is stable within a part in 10^11 at 1-s gate time and is currently limited by our reference signal. In order to develop this portable frequency standard, saturated absorption spectroscopy is performed on the acetylene v1+v3 band near 1532 nm inside different kinds of hollow optical fibers. The observed linewidths are a factor 2 narrower in the 20 um fiber as compared to 10 um fiber, and vary from 20-40 MHz depending on pressure and power. The 70 um kagome fiber shows a further reduction in linewidth to less than 10 MHz. In order to seal the gas inside the hollow optical fiber, we have also developed a technique of splicing the hollow fiber to solid fiber in a standard commercial arc splicer, rather than the more expensive filament splicer, and achieved comparable splice loss. We locked a CW laser to the saturated absorption feature using a Frequency Modulation technique and then compared to an optical frequency comb. The stabilized frequency comb, providing a dense grid of reference frequencies in near-infrared region is used to characterize and measure the absolute frequency reference based on these hollow optical fibers.

This study is primarily concerned with assessing the influence of the sex determination genes, transformer (tra), doublesex (dsx) and fruitless (fru) on three sexually dimorphic traits within Drosophila; pheromone blend, courtship song and sex comb tooth number. The sex determination loci have all been implicated as possible candidate genes affecting these important traits that contribute to sexual isolation, which is a major cause of speciation. Quantitative Trait Loci (QTL) analysis is used to assess the effects of these known candidate genes on the naturally occurring variation of mean interpulse interval (IPI) of courtship song and the differing pheromone blend profiles between Drosophila simulans and D. sechellia. The QTL analysis for both song and pheromone blend variation incorporated Multiple Interval Mapping (MIM), which enables the detection for epistasis. The desaturase loci desat1, desat2 and desatF were also included in the assessment on pheromone blends (cuticular hydrocarbon compounds), since they facilitate ecological adaptation and are also candidate genes, which are likely to exert a large affect on this particular trait. The sex determination genes were not significantly influential on the interspecific variation of the cuticular hydrocarbon compounds between these two sibling species. However significant effects were detected from two of the desaturase loci. desat1 was associated with a strong effect on the interspecific variation of a saturated hydrocarbon chain compound (unbranched-23). Additionally the candidate gene desatF potentially exerts an influence on the variation of 7,11-heptacosadiene, through a large epistatic effect with unidentified loci, situated between the markers pros and Mtn. The candidate gene eloF is situated in this region, and is known to affect the elongation of unsaturated hydrocarbon chains. The QTL associated with the marker desatF influenced the variation of both diene compounds (7,11-heptacosadiene and 7,11-pentacosadiene). Intriguingly epistasis was only detected for the variation of these two diene compounds. The MIM analysis assessing the affects of the sex determination genes on interspecific variation of mean IPI detected the candidate gene fru as the closest marker associated with a significant QTL on the third chromosome. The MIM also found a significant QTL associated with the marker Dgα situated on the second chromosome. Moreover significant epistatic interactions were detected between a further QTL situated nearest the marker forked on the X-chromosome with both of the other significant QTL situated on the third and second chromosomes. The analysis of a number of Recombinant Inbred (RI) lines was also carried out to test for the affects of the sex determination genes on both mean IPI and sex comb tooth number. The fru locus was associated with a significant increase in mean IPI, whereas the opposite was true for the dsx locus. In the analysis of sex comb tooth variation, it appears that all RI lines homozygous for D. sechellia alleles at the sex determination loci had significantly higher numbers of sex comb teeth. The final data chapter involves the sequence analysis of the fruitless locus, including all 13 fru proteins between ten recently sequenced Drosophilid genomes. The PAML program was used to detect the possible influence of natural selection on sequence divergence. There was no significant positive selection detected at the BTB functional domain and the sequences encoding for this domain were extremely conserved. Positive selection was found to be acting on the exon encoding for the Zinc-finger C domain. This domain is present in two protein isoforms including the male sex-specific isoform FRUMC, and the common non-sex-specific isoform FRUComC. Interestingly positive selection was also found at the non sex-specific Zinc-finger D domain.

The global traffic is experiencing an exponential growth posing severe challenges to the communication networks in terms of capacity. As a future-proof technology fiber communication is widely implemented in different network segments, which can be categorized by transmission distance as long-haul and short-reach. This thesis focuses on the short-reach communication networks including fiber access network connecting the end users to the metro/core networks that covering tens of kilometers and optical datacenter network handling the traffic within the datacenter with distance up to a few kilometers. For fiber access networks, wavelength division multiplexing passive optical networks (WDM-PONs) assign a dedicated wavelength channel to each user guaranteeing high data rate. Dense channels enlarges the user count but makes the signals vulnerable to the wavelength drift. In this regard we propose two schemes based on optical frequency comb technique to generate stable carriers for WDM-PONs. Meanwhile, radio-over-fiber techniques allows the transmission of radio signals between central offices and the cells. Millimeter wave (MMW) over fiber, on the other hand, offer high bandwidth for future high capacity mobile access. We propose and experimentally demonstrate a palm-shaped spectrum generation where the high-power central carrier can be used for upstream transmission while multiple MMW bands are capable of transmitting different downstream data simultaneously. Regarding optical datacenter networks, passive optical interconnects (POIs) have been proposed as an energy-efficient solution since only passive optical components are used for server interconnection. However, the high insertion loss may result in a scalability problem. We develop a methodology that considers various physical-layer aspects, e.g., receiver types, modulation formats, to quantify the scalability of POIs. Both theoretical analyses and experimental measurements have been performed to assess the scalability of various coupler-based POIs. / Den globala datatrafiken växer exponentiellt, både på grund av nya bandbreddskrävande applikationer och ökningen av antalet användare. Detta innebär en utmaning för kommunikationsnätens kapacitet. Fiberoptisk kommunikation är en framtidssäker teknik för att möta detta kapacitetsbehov och används redan i stor utsträckning i olika delar av näten. Beroende på överföringsavstånd, kan fibernät kategoriseras som långdistansnät eller nät med kort räckvidd. Denna avhandling behandlar nät med kort räckvidd, innefattande dels 1) accessnät som förbinder slutanvändarna till stadsnätet/ huvudnätet och typiskt omfattar tiotals kilometer, dels 2) optiska datanätverk som hanterar den interna trafiken inom datacenter med överföringsavstånd upp till ett par kilometer.För fiberaccessnät är en av de lovande teknikerna våglängdsmultiplexade passiva optiska nät (WDM-PON), där en dedicerad våglängdskanal tilldelas varje användare vilket garanterar hög datahastighet. Genom ett litet kanalavstånd så kan antalet användare i WDM-PON utökas men det gör samtidigt systemet känsligt för våglängdsdrift hos lasrarna. För att råda bot på detta, föreslår vi två system baserade på optisk frekvenskams-teknik. Vi validerar experimentellt att de kan generera stabila optiska bärvågor för WDM-PON. Radio-över –fiber-tekniken gör samtidigt det möjligt att sända radiosignaler över en lång sträcka och används därför i mobilsystem för överföring mellan centralstationen och radiocellerna. Millimetervågor (MMW) över fiber erbjuder ännu större modulationsbandbredd och är lovande för framtidens mobilradiosystem med hög kapacitet. I denna avhandling föreslår vi, och demonstrerar experimentellt, generation av ett frekvenskams-spektrum som är format som en handflata, där en central bärare med hög effekt (långfingret på handflatan) kan användas i radiocellerna för uppströms överföring, medan multipla MMW band (övriga fingrar) samtidigt kan överföra olika data nedströms. När det gäller nätverk för optiska datacenter, har passiva optiska interconnects (POI) föreslagits som en energieffektiv lösning, där endast passiva optiska komponenter används för ihopkoppling av servrarna. Höga inkopplingsförluster hos passiva optiska komponenter kan emellertid leda till allvarliga skalbarhetsproblem. I denna avhandling presenterar vi en nyutvecklad metod för att kvantifiera skalbarheten, vilken tar hänsyn till olika faktorer i det fysiska lagret som t.ex. mottagartyp och modulationsformat. Både teoretiska analyser och experimentella mätningar har utförts för att utvärdera skalbarheten hos olika kopplarbaserade POI. / <p>QC 20161117</p>

One of the best-known structures in Drosophila is the sex comb, an arrangement of modified bristles on the tarsal forelegs of males. This complex, sexually-dimorphic trait shows striking variation among closely related species, although most other aspects of the tarsal bristle pattern have been conserved. I studied the development of the sex comb in the model organism Drosophila melanogaster and six related species. I confirmed that the D. melanogaster sex comb, although longitudinal in the adult, originates in a transverse orientation and rotates during development, and showed that this process occurs through male-specific convergent extension. However, in the species that I examined that have longitudinally-oriented sex combs that extend the full length of the tarsus, including D. ficusphila and two species of the montium subgroup, the sex comb does not rotate, and instead forms from two longitudinal rows that converge during development. Another species of the montium subgroup, D. nikananu, has a sex comb that is convergently similar to D. melanogaster, but forms in a manner typical of its subgroup, showing that very similar combs can be formed through different processes. In all species, there is a strong correlation between the position of the sex comb and the transverse bristle row on the foreleg tarsus just proximal to it. To test whether it is possible to violate this apparent constraint on development, I perturbed the expression of the leg patterning gene dachshund to generate ectopic sex combs in D. melanogaster. I found that while most patterns showed the same correlation, a few circumvent the constraint. I also demonstrated that the ectopic combs were formed non-autonomously and that overexpression of dachshund can transform certain aspects of the sex comb phenotype to resemble the transverse bristles to which they are homologous.

One of the best-known structures in Drosophila is the sex comb, an arrangement of modified bristles on the tarsal forelegs of males. This complex, sexually-dimorphic trait shows striking variation among closely related species, although most other aspects of the tarsal bristle pattern have been conserved. I studied the development of the sex comb in the model organism Drosophila melanogaster and six related species. I confirmed that the D. melanogaster sex comb, although longitudinal in the adult, originates in a transverse orientation and rotates during development, and showed that this process occurs through male-specific convergent extension. However, in the species that I examined that have longitudinally-oriented sex combs that extend the full length of the tarsus, including D. ficusphila and two species of the montium subgroup, the sex comb does not rotate, and instead forms from two longitudinal rows that converge during development. Another species of the montium subgroup, D. nikananu, has a sex comb that is convergently similar to D. melanogaster, but forms in a manner typical of its subgroup, showing that very similar combs can be formed through different processes. In all species, there is a strong correlation between the position of the sex comb and the transverse bristle row on the foreleg tarsus just proximal to it. To test whether it is possible to violate this apparent constraint on development, I perturbed the expression of the leg patterning gene dachshund to generate ectopic sex combs in D. melanogaster. I found that while most patterns showed the same correlation, a few circumvent the constraint. I also demonstrated that the ectopic combs were formed non-autonomously and that overexpression of dachshund can transform certain aspects of the sex comb phenotype to resemble the transverse bristles to which they are homologous.

Domestic animals have rich phenotypic diversity that can be explored to advance our understanding of the relationship between molecular genetics and phenotypic variation. Since the advent of second generation sequencing, it has become easier to identify structural variants and associate them with phenotypic outcomes. This thesis details studies on three such variants associated with monogenic traits. The first studies on Rose-comb in the chicken were published over a century ago, seminally describing Mendelian inheritance and epistatic interaction in animals. Homozygosity for the otherwise dominant Rose-comb allele was later associated with reduced rooster fertility. We show that a 7.38 Mb inversion is causal for Rose-comb, and that two alleles exist for Rose-comb, R1 and R2. A novel genomic context for the gene MNR2 is causative for the comb phenotype, and the bisection of the gene CCDC108 is associated with fertility issues. The recombined R2 allele has intact CCDC108, and normal fertility. The dominant phenotype Greying with Age in horses was previously associated with an intronic duplication in STX17. By utilising second generation sequencing we have examined the genomic region surrounding the duplication in detail, and excluded all other discovered variants as causative for Grey. Dun is the ancestral coat colour of equids, where the individual is mostly pale in colour, but carries intensely pigmented primitive markings, most notably a dorsal stripe. Dun is a dominant trait, and yet most domestic horses are non-dun in colour and intensely pigmented. We show that Dun colour is established by radially asymmetric expression of the transcription factor TBX3 in hair follicles. This results in a microscopic spotting phenotype on the level of the individual hair, giving the impression of pigment dilution. Non-dun colour is caused by two different alleles, non-dun1 and non-dun2, both of which disrupt the TBX3-mediated regulation of pigmentation. Non-dun1 is associated with a SNP variant 5 kb downstream of TBX3, and non-dun2 with a 1.6 kb deletion that overlaps the non-dun1 SNP. Homozygotes for non-dun2 show a more intensely pigmented appearance than horses with one or two non-dun1 alleles. We have also shown by genotyping of ancient DNA that non-dun1 predates domestication.

During the years 2006-2010 Gotland University conducted seminars excavations in Västergarn parish on Gotland. Inside the wall a total of six house foundations have been found and a total of 127 combs have been registered. This thesis is based on a material study of the 127 registered medieval combs. The purpose of this thesis is to analyze the combs and with their chronology illuminate in which period the society of Västergarn was active. And also to find out what the material remains can tell us about the place and its people. The questions concern the dating and chronology of the combs, and also how analyzing the combs can provide additional information to Västergarn. The method used is a comparative material - and literature study. The result of the analyze is that the combs are from the transitional period of the Viking - Medieval age, 900- 1100th century. A variety of nine different types could be distinguished. I believe that through an osteological –, and contextual spatial analysis and a comparative material study of the combs more information on the site can be presented.

Les superplastifiants sont des adjuvants permettant de considérablement fluidifier les pâtes cimentaires sans en changer le rapport eau/ciment. Parmi eux, les polycarboxylates sont les plus utilisés et les plus étudiés. Ces copolymères en peigne sont porteurs de fonctions acide carboxylique et de chaînes latérales de poly(ethylène glycol). Leurs fonctions anioniques leur permettent de s’adsorber sur les grains de ciment, tandis que les chaînes latérales génèrent de la répulsion stérique entre ces derniers. Cela conduit à la désagglomération des agglomérats, et donc la dispersion des particules. Macroscopiquement, la pâte cimentaire devient plus fluide, plus facile à mettre en oeuvre. Mais dans certaines circonstances, la présence d’anions compétiteurs peut réduire la capacité d’adsorption et donc l’efficacité des polycarboxylates. De nombreux auteurs ont tenté d’améliorer les performances de ces structures en modifiant l’architecture macromoléculaire. Parmi ces travaux, des chercheurs ont remplacé les acides carboxyliques par des fonctions acide phosphonique, et cela a considérablement amélioré la résistance des superplastifiants au phénomène de compétition ionique.Ce travail de thèse rapporte la synthèse d’une dizaine de nouveaux copolymères en peigne, de structure proche de polycarboxylates classiques mais possédant des fonctions phosphonées. Ces copolymères ont été obtenus par télomèrisation ou bien par polymérisation radicalaire RAFT. Leurs performances ont ensuite été évaluées sur des suspensions minérales de carbonate de calcium, un matériau modèle souvent utilisé pour modéliser le comportement du ciment aux premiers âges de son hydratation. Les efficacités d’adsorption, de dispersion des particules minérales et de fluidification des suspensions ont ainsi été investiguées et mises en relation avec la structure macromoléculaire. De plus, leur résistance à la compétition ionique a également été examinée à travers l’augmentation de la force ionique par ajouts de sulfate de sodium et de nitrate de sodium.Enfin, ce manuscrit rapporte la tentative de conception d’un superplastifiant biosourcé à travers la fonctionnalisation d’oligomères de chitosan par des fonctions phosphonées et des chaînes latérales de poly(éthylène glycol). Les efficacités d’adsorption, de dispersion et de fluidification des suspensions de calcite de ce composé biosourcé ont finalement été évaluées et comparées à celles des copolymères en peigne de synthèse. / Superplasticizers are admixtures allowing the fluidification of cement pastes without any changes of the water/cement ratio. Among them, polycarboxylates are the most used and the most studied. These comb-like copolymers have carboxylic acid moieties and poly(ethylene oxide) side chains. Their anionic functions make possible their adsorption onto cement grains while side chains create steric repulsion between these latter. This leads to deagglomeration and dispersion of particles. From a macroscopic point of view, cement paste becomes more fluid, easier to place. But in some cases, competitive anions can reduce their adsorption ability and thus polycarboxylates dispersion efficiency. Lots of authors tried to improve structures performances by modifying macromolecular architecture. Among these works, some searchers have replaced carboxylic acids by phosphonic acid moieties, and this greatly improved superplasticizers resistance to ionic competition phenomenon.This work focuses on the synthesis of several new comb-like copolymers, whose structures are similar to conventional polycarboxylates but with phosphonic acid functions instead of carboxylic acids. These copolymers were obtained from telomerization or RAFT copolymerization. Their performances were evaluated on calcium carbonate suspensions, a model material widely used to simulate early-age cement behavior. Adsorption, dispersion and fluidification efficiencies of synthetized copolymers were examined and linked to their macromolecular structures. Moreover, their resistance to ionic competition was investigated through the increase of ionic strength by addition of sodium sulfate and sodium nitrate.Finally, this manuscript relates the conception of a biobased superplasticizer through the functionalization of oligomers of chitosan by phosphonated functions and poly(ethylene oxide) side chains. Adsorption, dispersion and fluidification efficiencies of this biobased compound were evaluated on calcite suspensions and compared to those of previously synthetized comb-like copolymers.