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The synthesis of medium-sized ring containing libraries using oxidative fragmentation and rearrangement strategies /Jones, Alan Morenc. January 2009 (has links)
Thesis (Ph.D.) - University of St Andrews, March 2009. / Restricted until 17th March 2011.
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Development of fragmentation techniques in mass spectrometry for biological applications /Ji, Hong. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.
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The environmental rule of law in IndiaMehta, Dhvani January 2017 (has links)
This thesis offers a new conceptual framework - the environmental rule of law - to describe weaknesses in the development of Indian environmental law, and uses this description to critique the dominant discourse on environmental institutional reform. A secondary framework-fragmentation is also used to supplement the analysis of Indian environmental law. Part I develops the conceptual framework of the environmental rule of law by considering the special challenges that the inherent polycentric and interdisciplinary nature of environmental law present for commonly understood rule of law values such as clarity, certainty and consistency. It also relies on Jeremy Waldron's conception of articulated governance to demonstrate that the rule of law is linked to the principle of separation of powers. This conception lays emphasis on the role of the three institutions of government - the legislature, the executive and the judiciary - in strengthening or weakening the rule of law. To determine institutional contribution to the rule of law, I develop three broad indicators to assess the legal quality of the instruments of each of these institutions of government. These indicators are: a) capacity of statutes to guide executive and judicial behaviour by goal-setting and balancing competing interests; b) the ability of the executive to make flexible yet reasoned decisions grounded in primary legislation; and c) the use of statutory interpretation and consistent standards of judicial review by the courts as they give effect to environmental rights and principles. Through the use of case studies in Part II that span environmental impact assessment, forest conservation, and indigenous rights, I demonstrate that the lack of adherence to these indicators produces a body of environmental law that is fragmented i.e. one characterised by multiple overlapping yet self-contained legal regimes with conflicting provisions and the absence of unifying norms. In Part III, I use this understanding of fragmentation to critically analyse environmental legal and institutional reform proposals. I show that existing proposals address only the structure, rather than the process of functioning of the institutions of government. The rule of law framework that I develop also has potential for application to other areas of the law.
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Landscape genetics of northern bobwhite and swamp rabbits in IllinoisBerkman, Leah 01 August 2012 (has links)
Northern bobwhite (Colinus virginianus) and swamp rabbits (Sylvilagus aquaticus) are species both strongly influenced by habitat loss and fragmentation in agricultural landscapes. Population declines for the bobwhite and the paucity of information regarding swamp rabbit prevalence add uncertainty to their potential for persistence in Illinois. Research has indicated that these 2 species rarely disperse long distances. In a metapopulation context, such limitations ultimately dictate species' ability to colonize habitat, thereby affecting their persistence. Since gene flow is one of the consequences of dispersal, I employed genetic investigations of the landscape features that affect gene flow, called landscape genetics, to aid the understanding of factors influencing the persistence of the northern bobwhite and swamp rabbit in an agricultural landscape. Tissue samples were collected from hunter harvested bobwhite in central and southern Illinois during 2007-2008. Tissue from trapped swamp rabbits and fecal pellets from swamp rabbit habitat were collected during 2004-2011 in the southernmost counties of Illinois. Microsatellite genetic markers were analyzed for each species. Bayesian clustering methods were used to find interbreeding groups. Levels of gene flow were assessed with F statistics. Correlations between individual genetic distances and landscape features provided an assessment of geographical attributes affecting gene flow. Northern bobwhite expressed less genetic structure among the southern and central counties of Illinois than expected from their sedentary reputation. Genetic differentiation among pre-defined subpopulations was low (FST <0.05) but significant. Genetic clusters were not tightly linked to geography. Individual-based analysis indicated that distance impacted gene flow more than the distribution of suitable habitat or highway barriers. Additionally, the distribution of suitable habitat on the landscape had a negative affect on gene flow indicating bobwhite may disperse through unsuitable habitat more readily than through suitable habitat. These results suggest that greater area of suitable habitat and improvement of existing habitat may be more beneficial to bobwhite than its arrangement or position on the landscape. Significant genetic structure was observed in swamp rabbits in the Cache River watershed of southernmost Illinois. Bayesian clustering indicated 4 distinct genetic groups inhabited the study area. Such structuring suggests swamp rabbits in the northernmost part of their range experience low connectivity among habitat patches and are consequently at risk for extinction in Illinois. Gene flow of swamp rabbits was tied to watercourses indicating their affinity for a water source impacts their dispersal tendencies. Gene flow was negatively impacted by highway barriers, which may interrupt swamp rabbit dispersal due to their avoidance of roads or land cover associated with roads. Alterations to swamp rabbit habitat that leads to loss, increased fragmentation, or increased road density may have severe negative impacts and should be avoided. Habitat improvement focused closer to watercourses may provide a greater benefit for swamp rabbits.
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The ecology of nest predation by red foxes Vulpes vulpesSeymour, Adrian S. January 2000 (has links)
No description available.
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Measurements of the φ∗η distribution of Z → µ+µ− events in pp¯ collisions at √s = 1.96 TeV and measurements of the isolated diphoton cross section in pp collisions at √s = 8 TeVLi, Xingguo January 2016 (has links)
Two precision measurements have been performed using the large number of dileptonand diphoton events produced in pp¯ and pp collisions. A measurement of thedistribution of the kinematic variable φ∗ηin the Drell-Yan process is performed inbins of boson rapidity and invariant mass using 10.4 fb−1 data collected by the D0experiment with a centre-of-mass energy of 1.96 TeV in pp¯ collisions. φ∗η, definedin terms of lepton track directions, is well-measured and is sensitive to higher ordereffects in Quantum chromodynamics (QCD). Data are compared to predictions fromstate-of-the-art QCD Monte Carlo programs and are in good agreement. Measurementsof the production of prompt photon pairs are performed using 20.24 fb−1 datacollected by the ATLAS experiment at 8 TeV in pp collisions. QCD Monte Carloprograms including higher order effects are found to describe the data. In addition,a luminosity algorithm that renders its susceptibility to noise and inefficiency of certainmodules in the diamond beam monitor has been proposed and validated usingATLAS simulations.
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Evaluate the Fragmentation Effect of Different Heap Allocation Algorithms in LinuxRentas, Dimitris January 2015 (has links)
Modern application are becoming more complex and demanding in terms of resource utilization. LTE network is part of those applications. Efficient memory utilization poses a great challenge to developers. The dynamic memory allocations and de allocations over the program execution time leads to a problem called memory fragmentation, which can eventually lead the system out of memory. Currently there are many allocators that are specifically designed for dynamic memory management. This thesis contains the study and analysis of three different allocators, ptmalloc2, tcmalloc and tlsf. The goal of the thesis is the evaluation of their performance in terms of memory fragmentation and cpu execution time. The allocators are tested against a real program tracing file, which contains a sequence of allocations and deallocations captured from an executing process.
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Aneuploidy and DNA fragmentation in morphologically abnormal spermTang, Steven Siu Yan 11 1900 (has links)
Introduction: Intracytoplasmic sperm injection (ICSI) has been a successful assisted reproductive technique for men with severe male-factor infertility. However, ICSI requires the subjective selection of normal looking sperm, which does not preclude the transmission of genetically abnormal sperm. Correlation between abnormal sperm morphology and chromosomal abnormalities has been suggested but not been conclusive and less is known about the connection between sperm morphology and DNA integrity. Sperm morphology will be evaluated on its ability to identify the level of chromosomal abnormalities or fragmented DNA in sperm. To further focus this investigation on sperm morphology, men with infertility isolated to abnormal sperm morphology (isolated teratozoopsermia) are examined.
Materials and Methods: Sperm from isolated teratozoopsermic men (n=10) were analysed by fluorescent in situ hybridization (FISH) and terminal dUTP nick-end labelling (TUNEL) assays to determine the level of aneuploidy and DNA fragmentation, respectively. These results were also compared to that of sperm from control men (n=9) of proven fertility and normal seminal parameters.
Results: Sperm from teratozoospermic men, compared to control men, had higher rates of total chromosomal abnormality (5.90±3.74% vs. 2.35±0.87%, P=0.0128), total aneuploidy (4.90±2.82% vs. 1.99±0.65%, P=0.0087), and chromosome 13 disomy (0.77±0.50% vs. 0.20±0.14%, P=0.0046). In control samples, incidence of tapered heads associated with supernumerary chromosomal abnormalities (rs=0.9747, P=0.0167). In teratozoospermic samples, incidence of amorphous heads associated to chromosome 13 disomy and sex chromosome aneuploidy (rs=0.6391, P= 0.0466; rs=0.8049, P=0.0050, respectively). Tail abnormalities were associated with chromosomal abnormalities (bent tail-disomy 13: rs=0.7939, P=0.0061; 2-tailed-disomy 13: rs=0.8193, P=0.0037; 2-tailed-supernumerary chromosomal abnormalities: rs=0.7534, P=0.0119). Levels of DNA fragmented sperm were higher in teratozoospermic men than control men (60.28±21.40% vs. 32.40±17.20%, P=0.0121). DNA fragmentation in sperm positively correlated with the incidence of sperm with bent necks in control samples (rs=0.8571, P=0.0238) and round headed sperm in teratozoospermic samples (rs=0.6727, P=0.0390).
Conclusions: Sperm of isolated teratozoospermic men have elevated rates of chromosomal abnormalities and DNA fragmentation compared to that of fertile controls. Specific abnormal sperm morphology can be correlated wiht chromosomal abnormalities and level of DNA fragmentation in sperm and this may prove useful in sperm selection for ICSI when applied to isolated teratozoospermic patients. / Medicine, Faculty of / Obstetrics and Gynaecology, Department of / Graduate
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Shock compression and dynamic fragmentation of geological materialsKirk, Simon January 2014 (has links)
This thesis investigated the shock compression and fragmentation of ge- ological materials with application to blast mining. Two geological materi- als were investigated; Lake Quarry Granite and Gosford Sandstone. Lake Quarry Granite was fully dense, while Gosford Sandstone was porous. The composition and microstructure of the materials were quanti ed and this information was later used in the analysis of their mechanical properties. The elastic sound speeds were measured for each material, from which their elastic moduli were derived. Gosford Sandstone had a reduced sound speed compared to its component minerals, which was analysed using geometric grain models and Hertzian contact theory. The shock Hugoniot of each ma- terial was measured though a series of plate impact experiments using a light gas gun. The experiments focused on the stress region of interest for blast mining, 0 to 12 GPa. The, fully dense, Lake Quarry Granite was found to have a constant shock speed, which agreed with the elastic longitudinal sound speed measured previously. As the material remained elastic, its Hugoniot was shown to be predictable using composite theory and the chemical com- position. The, porous, Gosford Sandstone underwent shock compaction and resulted in large variations in shock speed. The Hugoniot of Gosford Sand- stone was found to remain partially porous, even to high stresses, and was analysed using a P-a shock compaction model. Explosively-driven expanding ring fragmentation experiments were performed on Lake Quarry Granite to observed its fracture response under loading similar to those in blast mining. The experiments established that the fragment size reduced with loading strain rate until it reached the grain size. After this point the fragment size remained constant with increasing strain rate, a phenomenon not previously observed. The rock was found to be dominated by intergranular fracture, so the minimum achievable fragment size was the size of the grains with this failure mechanism.
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Modélisation discrète de la microstructure des agglomérats de particules fines en suspension / Discrete modeling of microstructure of fine particules agglomerates in suspensionKimbonguila Manounou, Adolphe 29 November 2013 (has links)
L'agglomération des fines entraîne une augmentation importante de la demande en eau des mélanges cimentaires et constitue un frein à la valorisation des sous-produits contenant des proportions élevées de fines. Une modélisation discrète de la microstructure des agglomérats de fines particules est développée. Le modèle intègre les forces de contact avec prise en compte du frottement et du roulement, les forces physico-chimiques et les forces hydrodynamiques calculées avec l'approximation de drainage libre. Le processus d'agglomération, de fragmentation et de restructuration sous cisaillement d'agglomérats fractals de fines particules minérales est étudié en vue de quantifier l'eau immobilisée dans les flocs. Un agglomérat initial isolé et lâche est soumis à un taux de cisaillement constant. Lorsque les forces hydrodynamiques sont prépondérantes par rapport aux forces de cohésion, l'agglomérat mère se fragmente en agglomérats secondaires jusqu'à atteindre un état stationnaire, où le nombre, la taille et la structure des flocs peuvent être considérés comme constants. L'influence du gradient de vitesse, du contexte physico-chimique, de la taille et de la polydispersité des particules sur les caractéristiques microstructurales des flocs à l'équilibre est étudiée. Il est montré que le comportement d'une suspension diluée monodisperse peut être décrit par un unique nombre adimensionnel faisant intervenir la force de cohésion maximale, la taille des particules et le gradient de vitesse. / The agglomeration of fines leads to a significant increase in water demand of cement mixtures and hinders the valorization of by-products containing high fines proportions. A discrete modeling of the microstructure of fine particles agglomerates is developed. The model takes into account contact forces, physico-chemical, and hydrodynamic forces computed with the free draining approximation. The agglomeration, fragmentation and restructuring process of fractal agglomerates of fine mineral particles under shear is studied to quantify the entrapped water in the flocs. A loose initial agglomerate isolated is submitted to a constant shear rate. When the hydrodynamic forces predominate over the adhesive forces, the parent agglomerate is broken up into secondary agglomerates until reaching a steady state, where the number, size and structure of flocs can be considered constant. The influence of the velocity gradient, the physico-chemical context, particles size and their polydispersity on the microstructural characteristics of flocs at steady state is studied. It is shown that the behavior of a monodisperse dilute suspensions can be described by a dimensionless single number involving maximum cohesion force, particle size and velocity gradient.
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