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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Fabrication and testing of 4.2m off-axis aspheric primary mirror of Daniel K. Inouye Solar Telescope

Oh, Chang Jin, Lowman, Andrew E., Smith, Greg A., Su, Peng, Huang, Run, Su, Tianquan, Kim, Daewook, Zhao, Chunyu, Zhou, Ping, Burge, James H. 22 July 2016 (has links)
Daniel K. Inouye Solar Telescope (formerly known as Advanced Technology Solar Telescope) will be the largest optical solar telescope ever built to provide greatly improved image, spatial and spectral resolution and to collect sufficient light flux of Sun. To meet the requirements of the telescope the design adopted a 4m aperture off-axis parabolic primary mirror with challenging specifications of the surface quality including the surface figure, irregularity and BRDF. The mirror has been completed at the College of Optical Sciences in the University of Arizona and it meets every aspect of requirement with margin. In fact this mirror may be the smoothest large mirror ever made. This paper presents the detail fabrication process and metrology applied to the mirror from the grinding to finish, that include extremely stable hydraulic support, IR and Visible deflectometry, Interferometry and Computer Controlled fabrication process developed at the University of Arizona.
72

Caractérisation des souches de Salmonella Typhimurium responsables de septicémies chez le porc

Lepage, Christine 05 1900 (has links)
Depuis quelques années, il y a émergence de souches de Salmonella enterica sérovar Typhimurium multirésistantes causant une septicémie et la mort chez le porc. Ceci constitue un problème majeur pour l’industrie porcine et possiblement pour la santé publique. L’objectif de ce projet était de comparer et de caractériser une souche capable de causer une septicémie chez le porc et une souche commensale, en observant l’interaction avec des cellules épithéliales, des macrophages humains et d’identifier des gènes exprimés par les souches septicémiques et les souches commensales. Tout d’abord, l’infection de cellules épithéliales permet d’observer l’adhérence et l’invasion des bactéries, pour ainsi mettre en évidence la capacité des souches à coloniser le tractus gastro-intestinal. La souche commensale possède un pouvoir d’adhésion supérieur à la souche septicémique. Par la suite, l’infection de macrophages permet de caractériser le niveau de phagocytose et de survie. L’importance de la survie dans les macrophages pourrait permettre de faire un lien avec la septicémie. Toutefois, aucune différence n’est observable dans les conditions qui ont été testé. Ensuite, la technique SCOTS (Selective Capture of Transcribed Sequences) est utilisée pour capturer des gènes uniques à la souche septicémique et un autre SCOTS est fait pour capturer les gènes spécifiques à la souche commensale. Finalement, les gènes sont clonés, leur spécificité face aux souches est analysé par dot blot et ils sont identifiés par séquençage suivient d’une analyses bioinformatiques. Les gènes identifiés par SCOTS, lors des captures pour la souche septicémique et la souche commensale, se trouvent à être des gènes communs aux Salmonella. Toutefois, la différence de pathologie causée par les deux souches, n’est peut-être pas l’acquisition de nouveaux gènes, mais plutôt une différence d’expression entre les deux souches. / For many years, there has been an emergence of new multi-drug resistant Salmonella enterica serovar Typhimurium strains responsible for high mortality rates in regards to swine infections. This represents a major problem for the swine industry and also for public health. The objective of this project was to characterize an isolate capable of creating swine septicemic illness and another which is naturally present in this host’s intestinal tract. The study conducted here includes observations of bacteria-epithelial cell interactions, bacteria-macrophage interactions and identification of genes expressed during different epithelial cell infections. Bacterial adherence and invasion of cells were observed after epithelial cell infection. This type of assay underlines the ability of the isolates to colonize the intestinal tract. The commensal strain has a better adherence then the other. Macrophage infections allowed characterization of bacterial phagocytosis and intracellular survival. Survival within macrophages reflects the capacity of the bacterial isolates to infect and survive in the host. There’s no difference between the two strains with the condition we test. A technique termed SCOTS (Selective Capture of Transcribed Sequences) was used to capture unique transcripts from the isolate which caused illness during swine infection. SCOTS was also used to find unique genes expressed by the commensal isolate. The captured fragments were cloned, their strain specificity was analyzed by dot blot and the genes transcribed were identified by direct sequencing followed by bioinformatic analysis. SCOTS carried out with the septicemic and the commensal isolates was done. During the SCOTS conducted with the strain isolated from a sick swine or with the isolate from healthy swine, common Salmonella genes were found. Thus, even though these two isolates cause different pathologies, virulence of the strains does not rely on the acquisition of new genes, but perhaps on differential gene expression among both.
73

Scots Under the Influence

Bills, Rebecca A. January 2009 (has links)
Thesis advisor: Michael J. Connolly / Old English, Old Norse (both Danish and Norwegian variants), Latin, Old French and various Celtic languages have influenced the development of the Scots language in different ways than they have British Standard English due to Scotland’s unique political relationships with each of these cultures. This paper explores the linguistic developments of these interactions, drawing examples from the Scottish poem Sir Patrick Spence, place names in Scotland, and other sources, with especial focus on the Germanic languages. / Thesis (BA) — Boston College, 2009. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program. / Discipline: Slavic and Eastern Languages.
74

Positive prescription of servitudes in Scots law

Peterson, Alasdair Stewart Sholto January 2017 (has links)
This thesis examines the establishment of servitudes by positive prescription in Scots law, with particular reference to the doctrine’s conceptual development and the nature of possession required under section 3 of the Prescription and Limitation (Scotland) Act 1973. The thesis is divided into three main parts. The first provides a historical account of the law of positive prescription as applied to servitudes from the 17th century to the 20th century, culminating in its statutory expression in section 3(1) and (2) of the 1973 Act. The second considers what the 1973 Act means when it says that a servitude must be “possessed” for the prescriptive period. While jurists in Scotland have traditionally thought that a right cannot be possessed as such, since it lacks a physical corpus, they have tended to view the apparent exercise of a right as equivalent to the detention of a corporeal object and concluded that servitudes can be “possessed” (or “quasi-possessed”) by analogy. An alternative approach is to say that, while possession denotes a comprehensive factual control of an object for one’s own benefit, certain lesser degrees of factual control are also protected by the law. On this view, the (apparent) exercise of a servitude constitutes a limited “possession” of the land itself and is protected accordingly. Part two argues that this alternative approach is the more coherent and provides helpful analytical tools for understanding what is really going on when a servitude is “possessed” for the purposes of prescription. The third part of the thesis consists of a detailed analysis of the nature of the possession required to establish a servitude by positive prescription. In particular, possession “as if of right” is shown to consist of two “steps”: firstly, the prescriptive claimant must show sufficient possession to indicate that a servitude is being asserted; and, secondly, the possession must not be “by right”, i.e. referable to another right already held by the claimant. After this, the statutory requirements of openness and peaceableness are considered in detail.
75

High Resolution Optical Surface Metrology with the Slope Measuring Portable Optical Test System

Maldonado, Alejandro V. January 2014 (has links)
New optical designs strive to achieve extreme performance, and continually increase the complexity of prescribed optical shapes, which often require wide dynamic range and high resolution. SCOTS, or the Software Configurable Optical Test System, can measure a wide range of optical surfaces with high sensitivity using surface slope. This dissertation introduces a high resolution version of SCOTS called SPOTS, or the Slope measuring Portable Optical Test System. SPOTS improves the metrology of surface features on the order of sub-millimeter to decimeter spatial scales and nanometer to micrometer level height scales. Currently there is no optical surface metrology instrument with the same utility. SCOTS uses a computer controlled display (such as an LCD monitor) and camera to measure surface slopes over the entire surface of a mirror. SPOTS differs in that an additional lens is placed near the surface under test. A small prototype system is discussed in general, providing the support for the design of future SPOTS devices. Then the SCOTS instrument transfer function is addressed, which defines the way the system filters surface heights. Lastly, the calibration and performance of larger SPOTS device is analyzed with example measurements of the 8.4-m diameter aspheric Large Synoptic Survey Telescope's (LSST) primary mirror. In general optical systems have a transfer function, which filters data. In the case of optical imaging systems the instrument transfer function (ITF) follows the modulation transfer function (MTF), which causes a reduction of contrast as a function of increasing spatial frequency due to diffraction. In SCOTS, ITF is shown to decrease the measured height of surface features as their spatial frequency increases, and thus the SCOTS and SPOTS ITF is proportional to their camera system's MTF. Theory and simulations are supported by a SCOTS measurement of a test piece with a set of lithographically written sinusoidal surface topographies. In addition, an example of a simple inverse filtering technique is provided. The success of a small SPOTS proof of concept instrument paved the way for a new larger prototype system, which is intended to measure subaperture regions on large optical mirrors. On large optics, the prototype SPOTS is light weight and it rests on the surface being tested. One advantage of this SPOTS is stability over time in maintaining its calibration. Thus the optician can simply place SPOTS on the mirror, perform a simple alignment, collect measurement data, then pick the system up and repeat at a new location. The entire process takes approximately 5 to 10 minutes, of which 3 minutes is spent collecting data. SPOTS' simplicity of design, light weight, robustness, wide dynamic range, and high sensitivity make it a useful tool for optical shop use during the fabrication and testing process of large and small optics.
76

Caractérisation des souches de Salmonella Typhimurium responsables de septicémies chez le porc

Lepage, Christine 05 1900 (has links)
Depuis quelques années, il y a émergence de souches de Salmonella enterica sérovar Typhimurium multirésistantes causant une septicémie et la mort chez le porc. Ceci constitue un problème majeur pour l’industrie porcine et possiblement pour la santé publique. L’objectif de ce projet était de comparer et de caractériser une souche capable de causer une septicémie chez le porc et une souche commensale, en observant l’interaction avec des cellules épithéliales, des macrophages humains et d’identifier des gènes exprimés par les souches septicémiques et les souches commensales. Tout d’abord, l’infection de cellules épithéliales permet d’observer l’adhérence et l’invasion des bactéries, pour ainsi mettre en évidence la capacité des souches à coloniser le tractus gastro-intestinal. La souche commensale possède un pouvoir d’adhésion supérieur à la souche septicémique. Par la suite, l’infection de macrophages permet de caractériser le niveau de phagocytose et de survie. L’importance de la survie dans les macrophages pourrait permettre de faire un lien avec la septicémie. Toutefois, aucune différence n’est observable dans les conditions qui ont été testé. Ensuite, la technique SCOTS (Selective Capture of Transcribed Sequences) est utilisée pour capturer des gènes uniques à la souche septicémique et un autre SCOTS est fait pour capturer les gènes spécifiques à la souche commensale. Finalement, les gènes sont clonés, leur spécificité face aux souches est analysé par dot blot et ils sont identifiés par séquençage suivient d’une analyses bioinformatiques. Les gènes identifiés par SCOTS, lors des captures pour la souche septicémique et la souche commensale, se trouvent à être des gènes communs aux Salmonella. Toutefois, la différence de pathologie causée par les deux souches, n’est peut-être pas l’acquisition de nouveaux gènes, mais plutôt une différence d’expression entre les deux souches. / For many years, there has been an emergence of new multi-drug resistant Salmonella enterica serovar Typhimurium strains responsible for high mortality rates in regards to swine infections. This represents a major problem for the swine industry and also for public health. The objective of this project was to characterize an isolate capable of creating swine septicemic illness and another which is naturally present in this host’s intestinal tract. The study conducted here includes observations of bacteria-epithelial cell interactions, bacteria-macrophage interactions and identification of genes expressed during different epithelial cell infections. Bacterial adherence and invasion of cells were observed after epithelial cell infection. This type of assay underlines the ability of the isolates to colonize the intestinal tract. The commensal strain has a better adherence then the other. Macrophage infections allowed characterization of bacterial phagocytosis and intracellular survival. Survival within macrophages reflects the capacity of the bacterial isolates to infect and survive in the host. There’s no difference between the two strains with the condition we test. A technique termed SCOTS (Selective Capture of Transcribed Sequences) was used to capture unique transcripts from the isolate which caused illness during swine infection. SCOTS was also used to find unique genes expressed by the commensal isolate. The captured fragments were cloned, their strain specificity was analyzed by dot blot and the genes transcribed were identified by direct sequencing followed by bioinformatic analysis. SCOTS carried out with the septicemic and the commensal isolates was done. During the SCOTS conducted with the strain isolated from a sick swine or with the isolate from healthy swine, common Salmonella genes were found. Thus, even though these two isolates cause different pathologies, virulence of the strains does not rely on the acquisition of new genes, but perhaps on differential gene expression among both.
77

Geographical distribution patterns of DNA polymorphism of scots pine (Pinus Sylvestris L.) at the eastern part of the species range / Paprastosios pušies (Pinus sylvestris L.) DNR polimorfizmo geografinio pasiskirstymo dėsningumai rūšies išplitimo areale

Buchovska, Jurata 18 December 2013 (has links)
In Lithuania, it is a first genetic study that analyses the DNA polymorphism of Scots pine at the level of cell’s nucleus and organelle’s genomes. In Europe, it is one of the first studies of DNR-based population structure covering in detail the eastern range of Scots pine, where the populations originate from Scotland in the west up to the Amur river estuary in the east. Our material represents a great magnitude of adaptive environments including the core populations at the central part of the species range as well as the marginal populations. The analysis was performed using high resolution and repeatability microsatellite DNA markers. / Tai yra pirmas genetinis mokslinis darbas Lietuvoje, nagrinėjantis paprastosios pušies DNR polimorfizmą ląstelės branduolio ir organoidų genomų lygmenyse. Europoje tai vienas iš pirmųjų mokslinių darbų, detaliai analizuojantis DNR polimorfizmą rytinėje paprastosios pušies rūšies arealo dalyje. Darbe lyginamos populiacijos, pradedant Škotija vakaruose, baigiant Amūro upės žiotimis tolimuose rytuose. Taip reprezentuojamas visas adaptacinių aplinkų gradientas: Europa–Uralas–Tolimieji Rytai. Tyrimui naudoti aukštos genetinės rezoliucijos ir patikimo pakartojamumo mikrosatelitinės DNR žymenys.
78

Defence responses of non-mycorrhizal and mycorrhizal seedlings of Pinus sylvestris L. to fungal pathogens

Bonello, Pierluigi January 1991 (has links)
The defence mechanisms expressed in roots of Pinus sylvestris seedlings challenged with fungal pathogens were investigated, and a comparison was made between the expression of defences in non-mycorrhizal and mycorrhizal seedlings. Papillae were formed by cortical cells of non-mycorrhizal seedlings infected with Cylindrocarpon destructans. Histochemical evidence was obtained for pectic materials comprising an important polysaccharide component of these structures, and for the deposition of polyphenolic compounds also. Proton induced X-ray emission (PIXE) microanalysis indicated that insoluble calcium levels were elevated in papillae relative to normal cell walls. Although papillae appeared important in protecting cortical cells against penetration by fungal hyphae, a primary role for the wall appositions in the resistance of seedlings of Scots pine against root pathogens could not be proven. Although phytoalexins were not detected in the roots of Scots pine seedlings following infection with C. destructans, the mean content of an abietic acid fraction (comprising six compounds, of which only dehydroabietic acid could be positively identified), increased from 5.2 to 9.7mg g<sup>-1</sup> dry weight. This fraction exhibited some antifungal activity. -related proteins induced de novo by infection could not be detected, but several constitutive apoplastic proteins, including some with chitinase activity, appeared to increase in the needles of root-infected seedlings. The formation of ectomycorrhizae with Pisolithus tinctorius, Suillus bovinus and Hebeloma crustuliniforme did not itself induce papilla formation in the roots of P. sylvestris. Evidence was obtained to suggest that the response was suppressed when mycorrhizal seedlings were challenged with C. destructans. Results highly suggestive of the induction of systemic resistance in P. sylvestris seedlings, consequent upon mycorrhizal infection, were obtained. In seedlings grown in vitro the survival rate of mycorrhizal seedlings challenged aerially with Botrytis cinerea was 37.5% compared with 7.1 in seedlings grown gnotobiotically. However, the physiological mechanisms by which this protection was imparted remain to be determined.
79

A contextual study of singing in the Fisher family

Smith, Stephanie Deborah Ladd January 1988 (has links)
This ethnographic study of a Scottish singing family, the Fishers of Glasgow, is based largely on fieldwork conducted over a period of three years. The Fishers were chosen because of their early involvement in, and their enormous influence on, the Scottish folk revival, which dates from the 1950s. Three members of the Fisher Family, Archie, Ray, and Cilia, sing professionally, and perform both traditional folksongs and contemporary material. This study focuses on them, although commentary about and from other family members is also included. In Chapter 2, I present a biography of the family, which is a patchwork of oral accounts by family members. Their biography leads us back to the islands of Vatersay and Barra, and the island traditions have obviously shaped the family ethos, even though they are an urban family. Chapter 3 is in part an oral history of the folk revival in Scotland, and the emergence of Archie and Ray Fisher as performers in the revival, as well as an analysis of important musical personalities and currents which had an impact on the revival, and particularly on Archie and Ray Fisher. Chapter 4 examines the professional careers of Archie, Ray, and Cilia, as well as the involvement of sisters Joyce, Cindy, and Audrey in the revival. The repertoire of the Fishers is examined in Chapter 5, with reference to the patterns of repertoire in the Scottish folk revival, and traditional sources. The way in which Archie, Ray, and Cilia categorize their songs is considered. Their categories, such as "heavy songs" and "light songs" tend to reflect the emotive impact of a song in performance, rather than structure. The problem of song "ownership" and repertoire within a family is also dealt with here. Chapter 6 focuses on the "aesthetic systems" of Archie, Ray, and Cilia, considering the following components: attraction to and selection of songs for learning; relative importance of tune and text; preferred song content; degree of emotional identification with songs; suitability of voice for a particular song; singing style; vocal range; the choice to accompany or not; the desired impact of the singer on the audience; the performing venue; and self-imposed expectations. The Fishers' aesthetic systems are also compared with those of other singers, both traditional and revival. In Chapter 7, I discuss the functions of songs in the Fishers' public performances, and analyse transcribed performance extracts of Archie, Ray, and Cilia (performing with her husband Artie). The spoken portion of the performances is seen as a significant and integral part of the performance as a communicative event. Analysis focuses on the structure of the performance, how the performance reflects the individual aesthetic system, and what levels of meaning may be derived from the performance. In Chapter 8, I conclude with a brief summary, and assess the place of the Fishers in the Scottish folk revival. Other data on the Fisher family, such as repertoire lists, a discography, and transcribed performance extracts may be found in the Appendices.
80

Effect of sewage sludge and clearfelling on the nutrient cycling of a mature Scots pine (Pinus sylvestris L.) stand

Mitchell, Diane January 1996 (has links)
The effects of sewage sludge application and the additional effects of clearfelling on nutrient cycling have been assessed in a mature Scots pine stand, north-east Scotland. The forest site was situated in a low rainfall area with high evapotranspiration and low leaching losses. The ground vegetation formed an important sink for N and P following sludge addition and clearfelling. Sludge application caused a foliar N response, increased foliar needle weight, and litterfall showed a significant and rapid potential to immobilize NH<sub>4</sub>-N and PO<sub>4</sub>-P added in sludge. The soil availability of NH<sub>4</sub>-N and PO<sub>4</sub>-P together with rates of mineralization of N and P and nitrification in sludge-treated areas were significantly increased compared with that of the control. Concentrations of NH<sub>4</sub>-N, NO<sub>3</sub>-N, PO<sub>4</sub>-P and organic P were increased significantly following sludge addition and fluxes were an order of magnitude greater than that of the control. Peaks in concentrations of NH<sub>3</sub>-N in sludge-treated areas exceeded the EC limit of 11.3 mg 1<sup>-1</sup> on several occasions. Of the total N and P applied to the sludge, throughfall and litterfall over a 17 month period, 2.4 % and 0.72 % were measured in the B<sub>s</sub> soil horizon flux. After clearfelling, initial increases in soil availability of NH<sub>4</sub>-N, NO<sub>3</sub>-N andPO<sub>4</sub>-P were measured. Felling increased nitrification rates, although increases were significant only in areas previously treated with sludge. Fluxes of NO<sub>3</sub>-N, NH<sub>4</sub>-N and PO<sub>4</sub>-P and organic P were increased at least an order of magnitude greater in felled areas than those of the control. Immobilization of N and P was greater in green and abscised litters placed in previously sludge-treated areas than compared with those placed in control areas.

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