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Pollination niches of Gymnadenia conopsea and G. densiflora in pure and mixed populations: evidence for character displacement?Olofsson, Caroliné January 2021 (has links)
Reproductive isolation can be achieved through multiple types of barriers and is essential for speciation. In flowering plants, pre-pollination barriers (e.g. differentiation in pollination niches) are believed to be the most efficient at preventing gene flow across species boundaries. In closely related species that come into secondary contact, such barriers can evolve to prevent competition for pollinator service and/or interspecific pollen transfer, which can have fitness costs. Hence pollination niche differentiation should be stronger in sympatric populations than in allopatric populations (i.e. character displacement). To investigate the differences in pollination niches and to see if it is consistent with a hypothesis of character displacement, I used the two closely related and phenotypically similar orchid species, Gymnadenia conopsea and G. densiflora. I sampled mixed and pure populations of G. conopsea and G. densiflora on Öland during the summer of 2020. In these populations, I used video cameras and pollinator catches to record pollinator activity and characterize the composition of pollinator communities. Estimation of pollinator efficiency was also assessed by analyzing the number of pollinia carried by each pollinator. Contrary to my expectations, I found that both orchids had their visitation peak during the night and that the most frequent and efficient pollinators were Autographa gamma or Deilephila porcellus for both of them. Furthermore, no increased differentiation between the two species was found in mixed compared to pure populations. My results suggest that plant-pollinator interactions do not act as efficient pre-pollination barriers in these two orchid species, and that competition for pollinator service and through interspecific pollen transfer seem to be too weak to drive pollination niche partitioning.
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濃厚水溶液を用いる金属電析プロセスに関する研究 / Metal Electrodeposition Processes Using Highly Concentrated Aqueous Solutions安達, 謙 24 September 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22068号 / 工博第4649号 / 新制||工||1725(附属図書館) / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 邑瀬 邦明, 教授 宇田 哲也, 教授 杉村 博之 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Optické měření deformací přírubových spojů / Optical measurement of deformations of flange jointsSchmidtová, Markéta January 2021 (has links)
The diploma thesis addresses the topic of optical measurements of flange joints during tightening and thermal loading. Commercially available optical systems with decreasing invasiveness were compared in opportunity which offer to an industrial environment. Various conditions are evaluated in 3D (scanning, DIC) as well as in 2D (DIC). The data for evaluation of sensitivity and system accuracy together with the evaluation of the data range were obtained by the measurement. Data evaluation showed the same accuracy for 2D and 3D system and the possibility of quality inspection of the joint by assessing the inspection dimensions in operation.
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Benefits And Detriments of Disaster-Related Shifts in Neighborhood Poverty: The Mediating Role of Contextual Resources and StressorsSpielvogel, Bryn January 2021 (has links)
Thesis advisor: Rebekah L. Coley / Recent decades have witnessed the increasing spatial concentration of poverty and affluence in the United States (Biscoff & Reardon, 2013). Given well-documented links between neighborhood economic contexts and wellbeing (Chow et al., 2005), this has the potential to exacerbate disparities in health, particularly for people with limited neighborhood choice. However, limited research has systematically examined the neighborhood features underlying these links. A more nuanced understanding of why neighborhood poverty matters is essential for promoting equitable neighborhood development. Using rigorous analytic techniques that account for the dynamic nature of neighborhoods and help adjust for selection bias, I considered two complementary questions: 1) do observed neighborhood resources and stressors mediate associations between neighborhood poverty and wellbeing within and between individuals; and 2) how do observed versus perceived changes in neighborhood features mediate links between neighborhood poverty and wellbeing? I combined individual-level longitudinal data from the Post-Katrina Study of Resilience and Recovery with administrative neighborhood data drawn from the Census Bureau, FBI, and EPA. Analyses focused on a sample of 606 participants – primarily young Black mothers with low levels of income – who were affected by Hurricane Katrina, most of whom experienced some period of forced relocation. Participants were surveyed once before (2003/04) and twice after (2006/07; 2009) the hurricane. Results paint a complex picture. Contrasting with prior research, total effects of neighborhood poverty on wellbeing were limited. However, changes in neighborhood poverty were linked to wellbeing indirectly through intermediary neighborhood features, with results pointing to benefits and detriments of rising neighborhood poverty. Results were driven by those who changed neighborhoods over the course of the study. For participants that lived in the same New Orleans neighborhood across waves, changes in neighborhood poverty proved less consequential. Overall, results suggest that rather than treating neighborhood poverty as uniformly problematic for wellbeing, efforts to promote health equity should identify and build upon existing assets of neighborhoods, like affordability and amenity access, while also reducing stressors. / Thesis (PhD) — Boston College, 2021. / Submitted to: Boston College. Lynch School of Education. / Discipline: Counseling, Developmental and Educational Psychology.
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Geodetické měření posunů a deformací dřevěné střešní konstrukce velkého rozpětí / Geodetic Deformation Measurement of Wide-Span Timber Roof StructuresKaras, Jindřich January 2013 (has links)
The aim of this thesis is deformation measurement of wide-span timber roof structures of swimming pool in Brno - Kohoutovice. The thesis deals with measuring of other stage, processing of surveying data, evaluation of deformation and graphic interpretation. Results of measurements follows up two stages in years 2009 and 2010. The part of the thesis is calibration measurement of surveying instruments and used measuring accessories.
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GNSS měření posunů v síti Sněžník / GNSS deformation measurement in the Sněžník NetworkSobek, Josef January 2013 (has links)
This thesis deals with a processing and evaluation of GNSS data measured during the years 2001 - 2012 in geodynamical network Sněžník. The aim of the thesis is a detection of possible horizontal and vertical displacements of points in this network. The thesis also deals with comparison of results determined by only GPS and both GPS and GLONASS measurements. Graphic interpretation of displacements’ evolution during the whole monitored period is one of the results of this thesis.
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Analýza doby příčného přemístění motocyklů / Analysis of the Lateral Displacement Time of MotocyclesFriedel, Daniel January 2013 (has links)
Diploma thesis named Analysis of the lateral displacement time of motorcycles captures formation and development of motorcycles, description of construction and proper techniques for riding a motorcycle. The main aim of this work is to organise and perform the measurement of the lateral displacement and deceleration of the motorcycles. These values will serve for forensic experts. Before the measurement was proposed methodology for the measurement of the lateral displacement by used two cameras and long chalk line. Follow measurement and evalution measurement of the lateral displacement and deceleration. Outputs from this thesis are values of the lateral acceleration necessary for calculation of the shortest lateral displacement time of the motorcycle and 96 videos with course and result of measurements.
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Trauma in Toni Morrison's Beloved : Literary Methods and Psychological Processes / Trauma i Toni Morrisons Beloved : litterära metoder och psykologiska processerNyberg, Rebecca January 2020 (has links)
In this essay, the novel Beloved, by Toni Morrison is observed using a working psychoanalytical approach. Story is observed as an important factor in engaging the reader on a personal level with the experience of trauma. By surveying Morrison’s use of imagery and language, this essay will examine how Morrison employs literary methods that imitate the psychological processes regarding how trauma is communicated to the waking state from the unconscious. The resulting testimony of the novel that arises as the result of these processes is also observed. This essay concludes that Morrison’s use of these literary methods functions to obligate the reader to involve themselves in the process of trauma and its resolution.
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Vliv různých druhů a poměrů mikrokrystalické celulosy a laktosy na fyzikální vlastnosti tabletovin a tablet. / Influence of different types and ratios of microcrystalline cellulose and lactose on physical properties of tablet blends and tablets.Machutková, Hana January 2016 (has links)
1 Abstract Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Departmanet of Pharmaceutical technology Consultant: doc. PharmDr. Zdeňka Šklubalová Ph.D. Student: Hana Machutková Title of Thesis: Influence of different types and ratios of microcrystalline cellulose and lactose on physical properties of tablet blends and tablets. In this study, the properties of tablet blends prepared from five different kinds of microcrystalline cellulose (Avicel ® A-101, 102, 105, 112, 200) and three types of lactose in different proportions were evaluated. Moisture content, the bulk and tapped density and the angle of repose were compared for tablet blends. The addition of lactose to the mixtures caused the decrease in the moisture content in the tablet blends. After evaluating the flow properties, the mixtures with suitable characteristics were compacted at compression forces of 8 and 12 kN. The force required to eject the tablet, the table strength, the disintegration time and the friability of the resulting tablets were estimated. The worst compressibility was identified for mixtures with higher concentration of Avicel 105. Due to its very small and fine particles (approximately 20μm) the filling of matrix was not uniform making tablet compression unsuccessful and thus the of uniform...
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Effects of air dissolution dynamics on the behaviour of positive-displacement vane pumps: a simulation approachFurno, Francesca, Blind, Vincent January 2016 (has links)
The aim of this paper is to evaluate the effects of the dissolution time – time for the liquid to absorb the gas till the saturation state - on the behaviour of positivedisplacement vane pumps, in terms of pressure peaks within internal chambers and forces applied to the stator ring. The chamber pressurization depends on the volume variation and fluid Bulk modulus in the pre-compression phase during which the volume is trapped between the suction and the delivery port rims. If the dissolution time is short, then the entrained air is quickly absorbed and the fluid Bulk modulus sharply increases just before opening the connection to the outlet; as a consequence, pressure peaks may appear thus degrading the NVH characteristics of the pump. Moreover the pressure within internal chambers generate i) a torque demand to the driver (the combustion engine or an electrical motor) and ii) a total force applied to the stator ring. In case of fixed displacement designs, the resultant pressure force simply represents a load for support bearings; while in case of variable designs, it contributes to the displacement regulation. Simulation results show that the pump behaviour is very sensitive to the dissolution time when it is quite close to the duration of the trapped period.
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