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1
Tobe, Rachel. "The Chimera." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1495807870248537.
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Hatleback, Eric Nelson. "Chimera of the cosmos." Thesis, University of Pittsburgh, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3647982.
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Multiverse cosmology exhibits unique epistemic problems because it posits the existence of universes inaccessible from our own. Since empirical investigation is not possible, philosophical investigation takes a prominent role. The inaccessibility of the other universes causes argumentation for the multiverse hypothesis to be wholly dependent upon typicality assumptions that relate our observed universe to the unobserved universes. The necessary reliance on typicality assumptions results in the Multiverse Circularity Problem: the multiverse hypothesis is justified only through invoking typicality assumptions, but typicality assumptions are justified only through invoking the multiverse hypothesis. The unavoidability of the circularity is established through argumentation for each of the two conjuncts that comprise it.
Historical investigation proves the first conjunct of the Multiverse Circularity Problem. Detailed study of the now-neglected tradition of multiverse thought shows that philosophers and scientists have postulated the multiverse hypothesis with regularity, under different names, since antiquity. The corpus of argumentation for the existence of the multiverse breaks cleanly into three distinct argument schemas: implication from physics, induction, and explanation. Each of the three argument schemas is shown to be fully reliant upon unsupported typicality assumptions. This demonstrates that the multiverse hypothesis is justified only through invoking typicality assumptions.
Philosophical assessment of cosmological induction establishes the second conjunct of the Multiverse Circularity Problem. Independent justification for typicality assumptions is not forthcoming. The obvious candidate, enumerative induction, fails: Hume’s attack against inference through time is extended to inference through space. This move undercuts external justification for typicality assumptions, such as the Cosmological Principle, which cosmologists implement to justify induction. Removing the legitimacy of enumerative induction shows that typicality assumptions are justified only through invoking the multiverse hypothesis, thereby establishing the Multiverse Circularity Problem.
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Envall, Pelle. "Accessibility planning : a chimera?" Thesis, University of Leeds, 2007. http://etheses.whiterose.ac.uk/11279/.
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This thesis investigates whether Accessibility Planning is a chimera. Is Accessibility Planning an illusion without reality, or is it a feasible planning Concept? Are accessibility-based planning approaches not already included in Mainstream transport planning practice? The objectives of the study are explored Through literature' reviews' and primary research of planning practitioners and Pedestrians. The literature reviews identify a number of potential barriers to Accessibility Planning through assessing research literature and collecting Information on previously abandoned approaches that were similar in scope to Accessibility Planning. The potential barriers were rephrased into eight research Propositions, divided into two groups, culture and tools. A further literature review And two surveys seek to answer the propositions. A survey of transport planners in British local authorities investigates difficulties in implementing Accessibility Planning and planners' attitudes to it. A second survey uses questionnaires and an Innovative GIS-based analysis to examine pedestrian route choice. The evidence Collected by the new GIS methodology assesses the reliability of 'local' Accessibility indicators based solely on notional distance. This part of the study also Presents new evidence on pedestrian route choice behaviour. Finally, the findings From the two surveys and the literature reviews are brought together and used to Confirm or reject the propositions. The results of the study portray how British. Transport planning culture has changed to take up an accessibility-based planning Approach and where the strengths and weaknesses of Accessibility Planning lie. The Study concluded that Accessibility Planning is not a chimera and that the tools that Have dominated transport planning do not incorporate an accessibility-based Planning approach. It also found that there is a significant problem in specifying Useful accessibility indicators, that this is an obstacle for effective Accessibility Planning, and that Accessibility Planning requires new skills and ways of working.
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Galbraith, Marshall C. "A Discontinuous Galerkin Chimera Overset Solver." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1384427339.
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Ruzzene, Giulia. "Control of chimera states in oscillator networks." Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/669638.
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Partial synchronization is an important phenomenon observed in nature and model systems. Chimera states are the most studied type of partially synchronized dynamics and attract interest from many fields of science. In homogeneous networks of identical oscillators, a chimera state is a symmetry broken dynamics in which the oscillators spontaneously split into two complementary groups: one in which they are synchronized and one in which they are not. The quest for chimera states in real-world scenarios has been made challenging by their unstable nature in systems of finite size. Therefore, it became crucial to find ways to control them. In this thesis we propose a new control method based on a pacemaker oscillator. We show how it can control all of the chimeras’ instabilities in networks of phase oscillators and we generalized this concept to more complex scenarios by applying it to multiplex networks of phase and FitzHugh-Nagumo oscillators.La sincronització parcial és un fenomen que s'observa en la naturalesa i en models matemàtics. Els anomenats estats quimera són entre els exemples més estudiats de sincronització parcial i atrauen l'interès de molts àmbits científics. En xarxes homogènies d’oscil·ladors idèntics, un estat quimera és una dinàmica en què es trenca la simetria perquè els oscil·ladors es divideixen espontàniament en dos grups complementaris: en un grup estan sincronitzats i en l'altre no. La cerca d’estats de quimera en escenaris del món real s’ha vist dificultada per la seva naturalesa inestable en sistemes finits. Per tant, és crucial trobar formes de controlar-les. En aquesta tesi proposem un nou mètode de control que utilitza un pacemaker (oscil·lador marcapassos). Mostrem com el pacemaker pot controlar totes les inestabilitats de les quimeres en xarxes d’oscil·ladors de fase i generalitzem aquest concepte a escenaris més complexos aplicant-lo a xarxes formades per capes d’oscil·ladors de fases i models de neurones de FitzHugh-Nagumo.
La sincronización parcial es un fenómeno importante que se observa en la naturaleza y en modelos matemáticos. Los denominados estados quimera son el tipo m\'as estudiado de dinámica parcialmente sincronizada y atraen el interés de muchos campos de la ciencia. En redes homogéneas de osciladores idénticos, un estado quimera es una dinámica con simetría rota en la que los osciladores se dividen espontáneamente en dos grupos complementarios: en uno están sincronizados y en el otro no. La investigación de estados quimera en escenarios reales se ha convertido en un desafío por su naturaleza inestable en sistemas finitos. Por lo tanto, es crucial encontrar forma de controlarlos. En esta tesis proponemos un nuevo método de control basado en un oscilador marcapasos (pacemaker). Mostramos cómo esto puede controlar las inestabilidades de las quimeras en redes de osciladores de fase y generalizamos el concepto a escenarios más complejos al aplicarlo a redes multi-capa de osciladores de fase y de modelos de neuronas de FitzHugh-Nagumo.
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Drozdek, Justyna. "Life and Chimera framing modernism in Poland /." online version, 2008. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=case1212425287.
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Mayor, Olivier. "Lineage analysis of neurogenesis in mouse chimera." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59410.
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To investigate the lineage relationships that are postulated to underlie the origins of phenotypically different neurons, Thy-1.1 $ leftrightarrow$ Thy-1.2 and hNF-L $ leftrightarrow$ +/+ mouse chimeras were examined for the distribution of the two neuron genotypes. Throughout the nervous system, a finely variegated pattern of mosaicism was always observed and, in each chimera, similar genotype proportions were found in all analysed neuronal populations of the peripheral and central nervous system. These findings require that the chimera neuroectoderm was a homogeneous mix of the two genotypes and that different neuronal phenotypes do not arise clonally from a small number of prespecified progenitors. Rather it would seem that all progenitors contribute daughter cells to all of the neuronal subpopulations at each level of the neuroaxis.
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Goh, Leong H. "The Chimera of the Asean regional security community." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA371203.
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Thesis (M.A. in National Security Affairs) Naval Postgraduate School, December 1999."December 1999". Thesis advisor(s): Mary P. Callahan. Includes bibliographical references (p. 113-117). Also available online.
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Herrmann, Anke. "Predicting nitrogen mineralization from soil organic matter - a chimera? /." Uppsala : Dept. of Soil Sciences, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a429.pdf.
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Anderson, Graham. "Organisational culture in English further education : chimera or substance." Thesis, University of Warwick, 2007. http://wrap.warwick.ac.uk/1115/.
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Since the mid-1970s there has been a greater emphasis placed on markets and competition as a means of allocating scarce resources. As a consequence of this the provision of public services has come under close scrutiny. In the English further education sector there has been structural and strategic change. The further education (FE) colleges are positioned to be able to play a key role in· the economic and social regeneration of the UK. The development- of 'managerialism' has occasioned the use of many practices and procedures more commonly associated with the private sector provision of goods and services. This study examines whether the concept of organizational culture has meaning and validity in a further education context. Research in this area is complex, time consuming and expensive. The concept of organizational culture is examined and evidence is gathered from a case study in Templeton College. The analysis of the evidence employs some of Pierre Bourdieu's concepts of the social world: field habitus and game. The evidence suggests that there is no integrated pattern of shared beliefs or behaviours that can claim to be a distinct entity. External factors are more likely to determine the situated social practices that exist within colleges. The case study approach has limited the external validity of the research and further analysis of . colleges is needed to verify the claims in this thesis. The study demonstrates that the migration of private sector management practices and concepts to the public sector is not an unproblematic process. FE would benefit from more extensive practitioner research; the more widely and deeply the colleges understand themselves the better chance for securing lasting improvements. Organizational culture is unlikely to be a significant lever of change in FE and colleges may be better advised to build a teaching and learning ethos.
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Tomlins, Steven. "In science we trust: Dissecting the chimera of New Atheism." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28795.
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New Atheism is a neologism that is explicitly linked to four public intellectuals: Richard Dawkins, Sam Harris, Christopher Hitchens, and Daniel Dennett. At the heart of this movement are the five books these four atheists have written specifically on the topic of religion. Throughout the New Atheist literature science is conceptualized as the most powerful force for secularization in the modern era. This thesis is a textual discourse analysis of the New Atheist literature, with a primary focus on how the themes 'secularization' and 'science' are framed. It will explore how notions of secularization and science often bleed into each other, with science being portrayed as necessarily opposed to religion. It will also highlight the New Atheists' similarities and diversities of opinion on these matters, as well as examine where their stances are located in the broader debates concerning the so-called secular/religious divide and the interactions between science and religion.
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Holloway, Zoe G. "Development of a fluorescent urokinase receptor chimera to study endocytosis." Thesis, Oxford Brookes University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402294.
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El, Feki Shereen Gwen. "CR1-CD59 chimera : a novel recombinant regulator of complement activation." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627074.
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Bashe, Akhona Carol. "The formalization of the informal sector economy : Panacea or Chimera?" Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/23264.
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In 2011 author Robert Neuwirth identified the global informal sector economy as having a combined Gross Domestic Product (GDP) that is equivalent to the second largest economy in the world behind the United States of America (USA).Studies have shown that the informal sector economy is prevalent in Africa and India which are both considered to be emerging market economies with potential for exponential growth. The GDP of a country is calculated using a total of a countries production of goods and services; however production in the informal sector economy is unaccounted for. The inclusion of their production could potentially boost the economic growth of these emerging market economies.This study aims to observe whether the informal sector economy should be formalized or left as it is in its current state. Despite the ‘problem statement’ in the previous paragraph, which appears to be in favour of formalization, there are advantages and disadvantages for both formalizing the informal sector economy and leaving it in its current state.The objective of this study is to come up with a sustainable strategy of how to manage and administer the informal sector economy as in its current state it is proving to be unsustainable.A two phased approach was used to produce the findings which included interviews with experts and interviews with entrepreneurs operating in the informal sector economy.These findings provided suitable recommendations to be made as to how to manage and administer the informal sector economy.Dissertation (MBA)--University of Pretoria, 2012.
Gordon Institute of Business Science (GIBS)
unrestricted
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Cleveland, S. Matthew. "HIV-1-specific antibody responses to a plant virus-HIV chimera." Thesis, University of Warwick, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340090.
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Voyevoda, Andriy. "The european energy union : an inevitable path or an everlasting chimera?" Master's thesis, Instituto Superior de Economia e Gestão, 2020. http://hdl.handle.net/10400.5/20712.
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Mestrado em Economia Internacional e Estudos EuropeusA integração gradual na Europa tem sido um lento mas constante processo, um processo que permitiu à União Europeia (UE) prosseguir iniciativas comuns nas esferas política e económica. Estas iniciativas permitiram o estabelecimento de um mercado comum de bens e serviços, uma união monetária, instituições políticas comuns, posições comuns em termos de política externa, entre outros aspetos que reforçaram a natureza sui generis da União Europeia enquanto organização supranacional . Apesar de um relativo sucesso nestas várias dimensões, o projeto europeu carece, ainda, de uma estratégia comum para a energia, o que é uma enorme desvantagem tendo em conta que a UE é altamente dependente de importações de combustíveis fósseis para satisfazer o seu crescimento económico. Com grande potencial para uma política comum no futuro, a agenda energética europeia não evoluiu ainda para o mesmo nível de integração que as políticas económicas e monetária, por exemplo. Deste modo, a presente dissertação focar-se-á na formulação da União da Energia Europeia, procurando analisar as diversas iniciativas adotadas pela UE para a concretização de uma estratégia energética comum.
The gradual integration in Europe has been a slow but steady process, a process that allowed the European Union (EU) to pursue common policies within the economic and political spheres. Such policies led to the establishment of a single market for goods and services, a monetary union, common political institutions, common standpoints in terms of foreign policy, and other shared aspects that added to the sui generis nature of the European Union as a supranational organization. Despite this relative success within a variety of policy dimensions, the European project still lacks a common strategy for energy, which is a huge liability given the fact that the Union, as a whole, is highly dependent on fossil fuels imports to satisfy its energy-hungry economic growth. With great potential for a future common stance, the European energy agenda has not yet evolved to the same integration level as the economic and monetary policies have, for instance. As such, the present dissertation focuses on the formation of the European Energy Union, seeking to analyze the several strategies partaken by the EU in order to complete a common energy strategy.
info:eu-repo/semantics/publishedVersion
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Null, Matthew Todd. "Capturing the Chimera: Ideology and Persuasion in the Rhetoric of Soulforce." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/34241.
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For more than half a century, gay rights organizations have sought cultural and political equality for lesbian, gay, bisexual, and transgender individuals in society. The organization Soulforce continues that legacy, but from a distinctive perspective. Soulforce, has positioned itself in a unique playing field by speaking directly to religious leaders and organizations in attempt to alter their ideological underpinnings and subsequently garner their support for LGBT individuals. This level of persuasion is particularly difficult due to the fact that religious ideology is so strongly held and protected in American society.
To evaluate the persuasive rhetoric of Soulforce, I conducted an ideological criticism of the documents published within the Soulforce website based on the foundation of McGee’s ideograph. The ideographs presented throughout the discourse coalesce to form the overarching ideology of Soulforce evidenced in the discourse. Lesbian, gay, bisexual, and transgender individuals experience unwarranted Master of Arts
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Eiben, Sabine. "CYP102A P450 monooxygenases: comparative analysis and construction of cytochrome P450 chimera." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-33683.
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Thoubaan, Mary Ghadbaan. "Dynamics and synchronization of weak chimera states for a coupled oscillator system." Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/34091.
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This thesis is an investigation of chimera states in a network of identical coupled phase oscillators. Chimera states are intriguing phenomena that can occur in systems of coupled identical phase oscillators when synchronized and desynchronized oscillators coexist. We use the Kuramoto model and coupling function of Hansel for a specific system of six oscillators to prove the existence of chimera states. More precisely, we prove analytically there are chimera states in a small network of six phase oscillators previously investigated numerically by Ashwin and Burylko [8]. We can reduce to a two-dimensional system within an invariant subspace, in terms of phase differences. This system is found to have an integral of motion for a specific choice of parameters. Using this we prove there is a set of periodic orbits that is a weak chimera. Moreover, we are able to confirmthat there is an infinite number of chimera states at the special case of parameters, using the weak chimera definition of [8]. We approximate the Poincaré return map for these weak chimera solutions and demonstrate several results about their stability and bifurcation for nearby parameters. These agree with numerical path following of the solutions. We also consider another invariant subspace to reduce the Kuramoto model of six coupled phase oscillators to a first order differential equation. We analyse this equation numerically and find regions of attracting chimera states exist within this invariant subspace. By computing eigenvalues at a nonhyperbolic point for the system of phase differences, we numerically find there are chimera states in the invariant subspace that are attracting within full system.
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Foschi, F. M. "DESIGN AND SYNTHESIS OF ALPHA-AMINO ACID AND MORPHOLINO `CHIMERA' BUILDING-BLOCKS." Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150054.
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SCUOLA DI DOTTORATO IN SCIENZE E TECNOLOGIE CHIMICHE
AA 2009/2010
XXIII CICLO Chimica Industriale
Dottorando: Foschi Francesca Matr.R07809
Tutor: Prof. Dario Landini Co-Tutor: Dr. Michele Penso
Design and synthesis of -amino acid and morpholino ‘chimera’ building-blocks
Non-natural quaternary α-aryl-α-amino acids are of great interest for their potential intrinsic bioactivity.1 here we reported the stereoselective conversion of a series of N-aryl-sulphonyl-α-amino acid t-butyl esters into the corresponding N-alkyl-α-aryl-α-amino esters. These α-quaternary compounds are obtained with good enantioselectivities (ee up to 98%) and high yields. This methodology has been applied to the transposition of both cyclic tertiary sulfonamide esters2 (i.e. proline derivatives) and open chain secondary compounds.3 These latter, in the first step, are N-alkylated and then rearrange to the target products.
This protocol has also been applied to the degradative rearrangement of a series of arylsulfonamido esters bearing on the aromatic ring different electron withdrawing groups.
The high enantioselectivity reached in this process, indicates that the stereochemical information is transferred from the N-alkylated sulfonamide A to the final rearranged product 2 via a chiral non-racemic enolate B. 4,5,6 This intermediate, through a Re-face attack, evolves into a chiral spiro-Meisenheimer complex that, in turn, undergoes the stereoselective S-Cα migration of the aryl group, with loss of sulphur dioxide.
As a second part of this PhD work, we improved a synthesis of 2,6-disubstituted morpholines by the double and consecutive oxirane ring-opening under SL-PTC, followed by regioselective conversion of only one hydroxy group into a leaving group.
Our background in the synthesis of 2,6-disobstituted morpholines, made us focus our attention on improving a chemical synthesis of morpholino monomer alternative to the Summerton approach, who is the sole known synthesis.
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Nilsson, Jakub. "Confusion Causing Chimeras : An evaluation of the Moral Confusion argument against the creation of human-nonhuman chimeras." Thesis, Umeå universitet, Institutionen för idé- och samhällsstudier, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-122674.
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Simon, Christine Anne. "The writing of a historical novel (entitled Chimera), together with an analytical commentary." Thesis, University of Chester, 2011. http://hdl.handle.net/10034/216810.
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Chimera is set in England and France in the present day and at the turn of the nineteenth century. Henri de Saint-Gilles was executed as a spy in London in 1813 on the evidence of his friend Richard Turnbull. Two hundred years later the novel’s twenty-first-century protagonists, Julia Dalton and Peter Marchmont, are both researching the events surrounding this incident. Marchmont, a delusional café-owner, is convinced that his ancestor Saint-Gilles was wrongly accused and that Turnbull was in fact the spy; since there is no evidence for this version of events, Marchmont has decided to produce it through an elaborate forgery. Dalton, an ambitious postgraduate student who has run out of leads in her research, agrees to pool resources with Marchmont. Her research takes her to Paris, where she meets the eccentric academic Mathias Fournier; together they visit the Château Ruffec, the Saint-Gilles family seat, in the Charente. Here and at the university of Poitiers, they discover documents written by Saint-Gilles’s sisters, Rosine and Manon, concerning a visitor to the château in the summer of 1794. This visitor, who is also the father of Rosine’s illegitimate son, is subsequently discovered to be Richard Turnbull, a fact which has dramatic implications for Marchmont’s understanding of his ancestry. Dalton’s boyfriend Miles Carter, a police detective, has meanwhile become suspicious of her relationship with Marchmont and begins his own investigations, looking into Marchmont’s past and his connection with the career criminal Drue Paulin whom he has employed to steal documents to order. In this novel, past and present are interwoven. The historical narrative proceeds through fictional fragments of varying length, such as diaries, letters and memoirs, many of them written by Turnbull. These alternate with the twenty-first-century narrative and occur in the order of their discovery; thus the historical story is not presented chronologically but jumps around in time. It is also incomplete: there are hiatuses in the narrative, some of which are not explained. Running through the novel, but separate from the main narrative, are the sections of Saint-Gilles’s trial; these provide an official version of events which is complicated, and in places contradicted, by the rest of the narrative. A significant element of the plot concerns Turnbull’s hunt for the French spy in 1812. This is narrated in a journal purloined by Dalton early in the novel, but most of which she is unable to decipher until much later. (Her possession of this journal eventually enables her to detect a factual error in Marchmont’s forgery which would otherwise have gone unnoticed.) The concept of the past is here complicated by the fact that the events of 1812 are linked in Turnbull’s eyes with two significant episodes in his past: the death of his mother in 1788 following her entry into an extreme religious community run by the eccentric preacher Ezekiel Juggins; and an episode of both personal and political significance, only partially explained, which took place in Paris in 1793-94. All the characters involved in these earlier incidents (Juggins, Saint-Gilles and the American John Newman) happen to be in London in the summer of 1812 and are investigated by Turnbull; it is not entirely clear, however, to what extent his official remit masks a personal one. The open-ended nature of research and the relative nature of time are emphasized by the novel’s coda, which takes place in 2028; Dalton receives from Mathias Fournier a copy of two letters written by Richard Turnbull from Paris detailing his meeting in 1825 with the son whom he had believed, on Saint-Gilles’s word, to have died at the age of fourteen. Ambiguity is a major theme in this novel, and to express this the wave-particle complementarity of light has been used, both thematically and as a metaphor. Much of the plot of Chimera rests on Turnbull’s identity: was he a government agent, a French spy or a mere wandering scholar? Dalton considers the idea that Richard Turnbull might best be understood, like light, in terms of a ‘both/and’ paradigm rather than an ‘either/or’ one. The purpose here has been to link forms of duality and ambiguity which have long been recognized in literature (paradox, spying and betrayal, for example) with what appears to be a fundamental ambiguity at the heart of the material universe. One of the intentions underlying this novel was to produce a work which combines plot and suspense with intellectual weight. Through its use of subjective narrative as the means by which the historical plot is advanced, Chimera foregrounds the process of research and the slipperiness of narrative, whether historical or fictional. It is meant to raise questions surrounding the nature of textual evidence: the way in which it influences our view of history; the tension between subjectivity and objectivity; the sometimes tenuous relationship between ‘truth’ and ‘fiction’. The accompanying analytical commentary consists of five essays. The first examines various aspects of the writing of the novel; it discusses the origins of Chimera, some of the influences on it and the narrative techniques and decisions which informed it, including the ways in which the quantum theory of light has been incorporated into the narrative. The remaining four chapters discuss the main areas of research which contributed to the writing of the novel. First, two key texts are analyzed: Thomas Mann’s Doctor Faustus, a polyphonic novel which examines the rise of Nazism in Germany, and John Banville’s The Untouchable, a roman à clef based on the life of Anthony Blunt. These untypical examples of the amorphous genre of historical fiction share features, both with each other and with Chimera; in addition, they demonstrate how history may be incorporated into fiction in an intelligent and imaginative way. Chapter IV, ‘Conventicles and Politics’ discusses some of the essential historical research necessary for the writing of Chimera. The themes of dissenting religion and political radicalism are central to this novel (they are brought together in the opposition of Richard Turnbull and Ezekiel Juggins); the complex relationship between them in the late eighteenth and early nineteenth centuries was a defining feature of this period and provided a focus for the historical research carried out during the writing of the novel. Chapter V of the commentary combines a discussion of both history and science. First, it examines the historical controversy surrounding the nature of light in the early nineteenth century, a controversy touched on by Richard Turnbull in his account of Thomas Young’s lecture on light at the Royal Society in 1803. Young’s double-slit experiment is then compared with that of Richard Feynman in the twentieth century, and the implications of wave-particle complementarity are discussed.
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Francalanza, Laura. "Exploring Central Collisions in the Reaction 58Ni+48Ca at 25 AMeV with CHIMERA." Doctoral thesis, Università di Catania, 2015. http://hdl.handle.net/10761/1715.
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In this PhD thesis it is presented the study concerning the competition of different reaction mechanisms in central collisions at Fermi energies, with particular interest on the onset of multifragmentation phenomena as a possible evolution of evaporative processes toward more explosive mechanisms.
This study has been carried out through the analysis of the 58Ni + 48Ca reaction at 25 AMeV, performed at the Laboratori Nazionali del Sud in Catania by the ISOSPIN and NUCL-EX collaborations in 2003 by using the CHIMERA multidetector.
As a main criterion for centrality selection we have chosen the event shape method, based on the construction of the kinetic energy tensor for the analysis of the configuration of the matter in the momentum space at the decay stage. It has been noticed how a cut on the shape variable "flow angle" (at 60 degrees) obtained by the diagonalization of the tensor resulted in a strong reduction of peripheral and semiperipheral less dissipative events, and in a very stringent selection of single compact sources, on an event by event basis.
This latter feature has been highlighted by the analysis of other event shape variables like the sphericity and the coplanarity and their correlations. Moreover, the main properties of the reaction products were explored by using different constraints on some of the relevant observables, like mass and velocity distributions and their correlations.
Much emphasis was devoted, for central collisions, to the competition between fusion-evaporation processes with subsequent identification of a heavy residue and a possible multifragmentation mechanism of a well defined (if any) transient nuclear system. A dominance of evaporative (sequential) mechanisms together with evidences of more fragmented processes has been highlighted and the two different contributions to emission have been firstly disentangled by a cut on the mass value of the heaviest fragment detected in each event (at A(1) = 40 amu) and then characterized.
Dynamical evolution of the system and pre-equilibrium emission were taken into account by simulating (with BNV calculations) the reactions in the framework of transport theories. Afterwards, the de-excitation of such sources was carried out by means of the SIMON code, that followed decay of the formed nuclei via binary sequential emissions of fragments and light particles.
Preliminary results show reasonable agreement with the assumption of sequential multifragmentation emission in the mass region of IMFs close to the heavy residues. Deviations from sequential processes were found for those IMFs in the region of masses intermediate between the mass of heavy residues and the mass of light IMFs. Such a region has been finally the object of a termodinamical analysis in terms of excitation energy estimation (both from calorimetric method and theoretical computations ) and apparent temperature evaluations through the isotopic ratio thermometer applied on light emitted nuclei (Li, Be and C): results are in quite in agreement with the existent systematic of excitation the energy and temperature correlation.
It could be very interesting to enlarge such analysis by studying the evolution of the reaction mechanisms with increasing of the incident energies and by investigating its isospin dependence. This will be possible by exploring those variables sensitive to the symmetry energy in the comparison with other systems as 58,62Ni+40,48Ca in the reactions at 25 AMeV and 35 AMeV carried out by the collaboration.
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Kancharla, Jahnavi Reddy. "Generation of Transgenic Medicago Sativa Overexpressing "Osmotin-Chitinase" Gene Chimera." TopSCHOLAR®, 2011. http://digitalcommons.wku.edu/theses/246.
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Medicago is widely used as a forage crop. It is often susceptible to various pathogenic infections and exhibits low growth in drought and extreme climatic conditions. In the current study, a strategy was developed for over-expressing an “Osmotin-Chitinase” gene chimera in transgenic Medicago that could potentially confer resistance to different biotic and abiotic stresses. Seed germination of several cultivars of Medicago (M. sativa ssp. sativa, M. sativa ssp. falcata, M. sativa ssp. caerulea, M. truncatula, and M. Rugosa) was tested to determine the cultivars with good germination rates. Among these, M. sativa ssp. sativa showed an average of 80% germination over a period of one week and was subsequently selected for regeneration and transformation experiments. Different explants (cotyledons, hypocotyls, petioles) were tested for regeneration. Among these, hypocotyl explants showed highest (46.17 %) percent regeneration. Escherichia coli harboring Osmotin-Chitinase (OSM-CHI) gene chimera cloned into binary vector pBTEX with nptII as a selection marker was mobilized in Agrobacterium tumefaciens strain EHA105 which was employed in the transformation of hypocotyl explants of Medicago. Transformed calli were grown on callus inducing medium containing kanamycin for screening. Further screening of the positive transgenics was performed using PCR. Southern hybridization was carried out for further confirmation of successful transformation. Transformed shoots will be grown on the root inducing medium for developing into plantlets which would then be transferred to the green house and later tested for their degree of resistance to various biotic and abiotic stresses.
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Mazaki, Fatima Zahra. "Étude narrative de The Floating opera, Lost in the funhouse et Chimera de John Barth." Paris 4, 1995. http://www.theses.fr/1995PA040077.
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Cette recherche étudie la forme narrative dans The Floating opera, Lost in the funhouse et Chimera de John Barth. La première partie de cette étude traite du problème de la communication et du rôle du narrataire, adressé comme you, dans l'organisation du passe de Todd Andrews: narrateur à la première personne de The Floating opera. La deuxième partie est consacrée à l'analyse des labyrinthes dans Lost in the funhouse. Parmi les principaux éléments qui constituent les labyrinthes verbaux, nous avons discuté les "blancs" et les lacunes. Quant aux labyrinthes structuraux, ils sont créés par le point de vue, l'allusion et la ponctuation. La troisième partie traite des trois novellas de Chimera. Dans chaque novella, Barth, narrateur des histoires à la première personne, parodie les éléments traditionnels de la fiction et essaie de trouver de nouvelles formes du récitThis thesis studies the narrative form in John Barth's The Floating opera, Lost in the funhouse and Chimera. The first chapter examines the problem of communication and the role played by the narratee, addressed as "you", in the organization of the past of Todd Andrews: first person narrator of The Floating opera. The second chapter discusses Barth's use of labyrinths in Lost in the funhouse. Blanks and lacunae are the most two important verbal labyrinths. The other narrative devices to create structural labyrinths are point of view, punctuation and allusion. The third chapter studies the three novellas of Chimera. In each novella, Barth, speaking as first person narrator, parodies point of view, characterization, plot and setting, and tries to discover new forms of narrative
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Woodrow, Kristina L. "Dialogue of the sphinx and the chimera : the dialectic of Gautier's poetics in "Emaux et camees" /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487864986611507.
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Grassi, Laura. "Nuclear reactions induced by light exotic nuclei produced at INFN-LNS and studied by CHIMERA multidetector." Thesis, Universita' degli Studi di Catania, 2011. http://hdl.handle.net/10761/126.
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Progress in nuclear science is often driven by new accelerator and other advanced facilities, which allow probing ever more deeply into the structure of the nucleus, or even to discover new states of the nuclear matter. At Laboratori Nazionali del Sud in Catania, using as primary beams 18O and 13C at 55 MeV/u impinging on 9Be production target, light radioactive ion beams have been produced through In Flight Fragmentation method. Elastic scattering angular distributions of 16C+p and 16C+d at 50 MeV/u, 10Be+p at 56 MeV/u and 13B+d at 52 MeV/u systems are measured by using kinematical coincidence technique.
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Joe, Patrick Allen. "A structure-function study of the cysteines and carboxy-terminal tail domain of the beta-III tubulin isotype a dissertation /." San Antonio : UTHSC, 2008. http://learningobjects.library.uthscsa.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=43&CISOBOX=1&REC=18.
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Stern, Louis G. "An explicitly conservative method for time-accurate solution of hyperbolic partial differential equations on embedded Chimera grids /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/6758.
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Kozłowska, Izabela. "Behavior of chicken primordial germ cells injected into the bloodstream of recipient embryo." PhD diss., University of Science and Technology, 2015. http://dlibra.utp.edu.pl/Content/834.
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Aim of study was to investigate behavior of donor and recipient PGCs by 1. isolation method of gonadal PGCs from 28-29 (H&H) stage donor embryos to obtain possible highest number of non-aggregating cells; 2. examination of migratory capabilities of PGCs derived from Ross 308 and green-legged partridgelike in the role of donor or recipient of cells; 3. elaboration a new method of partial sterilization of recipients using cytostatic- terosulfan (TERO)
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Bozick, Mona. "Textuality of Flesh." Connect to resource online, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1244561867.
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Boykin, Jasmine. "Validation of Chimeric Viruses in Plaque Reduction Neutralization Test in Arboviral Disease Diagnostics." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7001.
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The plaque reduction neutralization test (PRNT) is a confirmatory diagnostic assay that is used to confirm a variety of diseases. The performance of PRNT requires the use of infectious wild type viruses, which increases the risk of laboratory acquired infections. For instance, eastern equine encephalitis (EEEV) is a highly virulent pathogen used in PRNT that can result in potentially fatal neurological diseases among humans and equines. Therefore, arboviral PRNT must be performed in Biosafety Level 3 (BSL-3) containment facilities and may require select agent approved scientists, like in the case of EEEV. These stringent requirements restrict the ability of public health laboratories to conduct PRNTs. Chimera viruses, recombinant constructs that have been bio-engineered to express the immunogenic structural proteins from the wild type virus in an attenuated form, can serve as a substitution for infectious viruses when performing PRNT. Since chimera viruses do not require the use of a BSL-3 facility and are not classified as select agents, their use offers advantages over wild type viruses. This study aimed at validating the use of EEE and West Nile chimera viruses as an alternative to the corresponding wild type viruses for diagnostic purposes at the Florida Department of Health (FDOH) Bureau of Public Health Laboratories (BPHL). These evaluations were conducted using human and avian sera. The results illustrate that chimera virus-based PRNT portrays specificity comparable to that of the wild type virus, while a slight reduction in sensitivity was observed when human sera was used. Considering their benefits in increasing safety and reducing regulatory requirements, these chimera viruses are an important alternative to the virulent wild type viruses and could be highly beneficial for diagnostic laboratories.
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Pluchino, Kristen Marie. "Generation of chimeric P-glycoprotein for functional and structural investigations." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:4f5c9dcc-401c-4123-9b2f-c5d17e0d7bc2.
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A major challenge in cancer treatment is acquired or intrinsic multidrug resistance (MDR) to chemotherapeutics. A notorious mediator of MDR is P-glycoprotein (P-gp, ABCB1), product of the human MDR1 gene, which actively effluxes cytotoxic drugs from cancer cells, resulting in sub-therapeutic intracellular concentrations. Understanding how P-gp interacts with drugs has been severely limited by the lack of high-resolution structures of P-gp. Although numerous efforts to obtain an X-ray crystal structure of P-gp have been attempted, human P-gp has never been crystallized. However, mouse P-gp (87% homologous to human P-gp) has been crystallized, and several structures of mouse P-gp have been recently reported. Despite a high degree of homology, it is currently unknown why mouse P-gp can be crystallized while human P-gp cannot. The studies presented in this thesis describe the creation of novel chimeras of mouse and human P-gp as an approach to investigate whether specific protein domains are responsible for differences in the ability to form crystals between mouse and human P-gp. A range of chimeras, created by protein domain swapping, were expressed in mammalian cells and all were found to retain MDR transport function demonstrating that P-gp can tolerate major structural changes. High-level expression of all chimeras was achieved by baculovirus-mediated heterologous protein expression. Chimeric proteins were purified by a multi-step process including immobilized metal affinity chromatography and size exclusion chromatography. Crystallization screening obtained protein crystals for two of the chimeras, indicating the approach adopted is a successful strategy, and an advance along the path towards a high-resolution structure of human P-gp.
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Wheeler, Lee Adam. "CD4 Aptamer-SiRNA Chimeras (CD4-AsiCs) Knockdown Gene Expression in CD4+ Cells and Inhibit HIV Transmission." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10272.
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The continued spread of HIV underscores the need to interrupt transmission. One attractive strategy is a topical microbicide. Sexual transmission of herpes simplex virus type 2 (HSV-2) in mice can be inhibited by intravaginal small inhibitory RNA (siRNA) application. To overcome the challenges of using siRNAs to knock down gene expression in immune cells susceptible to HIV infection, we used chimeric RNAs composed of an aptamer fused to an siRNA for targeted gene knockdown in cells bearing an aptamer-binding receptor. Here, we showed that CD4 aptamer-siRNA chimeras (CD4-AsiCs) specifically suppress gene expression in CD4+ T cells and macrophages in vitro, in polarized cervicovaginal tissue explants, and in both the genital and rectal tracts of humanized mice. CD4-AsiCs do not activate lymphocytes or stimulate innate immunity, provide durable target gene silencing for up to three weeks in vitro, and maintain effectiveness in a hydroxyethyl cellulose (HEC) gel formulation. CD4-AsiCs that knock down HIV genes and/or CCR5 inhibited HIV infection in vitro and in cervicovaginal explants. When applied intravaginally to humanized mice, CD4-AsiCs provided durable protection against transmission of the virus. Thus, CD4-AsiCs could be used as the active ingredient of a microbicide to prevent the sexual transmission of HIV.
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Blignaut, Belinda. "Improved vaccines for foot-and-mouth disease control : evaluation of a chimera-derived FMD vaccine in relation to a current SAT type vaccine." Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/30806.
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Foot-and-mouth disease virus (FMDV), a member of the Picornaviridae, causes a highly
contagious disease that affects cloven-hoofed animals and leads to production losses,
especially in intensive farming systems. In sub-Saharan Africa, control of the disease is
complicated by the extensive variability of the South African Territories (SAT) type viruses,
which exist as distinct genetic and antigenic variants in different geographical regions.
Improved control of FMD, therefore, requires vaccines to be custom-made to specific
geographical areas. In this regard, a potentially powerful approach involves the engineering
of chimeric FMDV of which the antigenic properties can be readily manipulated.
Consequently, the aim of this study was essentially to evaluate a custom-engineered chimeric
FMD vaccine in relation to a current SAT type vaccine.
To enable the selection of vaccine strains that would provide the best vaccine match against
emerging viruses, phylogenetic, genetic and antigenic analyses of SAT serotypes prevalent in
sub-Saharan Africa was performed. The results indicated that although SAT1 and SAT2
viruses displayed similar genetic variation within each serotype, antigenic disparity, as
measured by r1-values, was less pronounced for SAT1 viruses compared with SAT2 viruses. Consequently, the SAT1 virus KNP/196/91 was selected and a cross-serotype chimeric virus,
vKNP/SAT2, was engineered by replacing the external capsid-encoding region (1B-1D/2A)
of an infectious cDNA clone of the SAT2 vaccine strain, ZIM/7/83, with that of KNP/196/91.
The population diversity of the cell-adapted chimeric virus and pig-adapted KNP/196/91 virus
was investigated by means of pyrosequencing; the results of which indicated that the
population diversity of the respective viruses was indeed comparable to each other.
Subsequently, chemically inactivated vaccines were produced from intact 146S virion
particles of both the chimeric and parental viruses and evaluated in a full potency test. Pigs
vaccinated with the chimeric vaccine produced neutralising antibodies and showed protection
against homologous FMDV challenge.
Cumulatively, the data provide support that chimeric vaccines containing the external capsid
of field isolates can be successfully produced and that they induce protective immune
responses in FMD host species. The potential therefore exists to generate more effective newgeneration
chemically inactivated-FMD vaccines that are custom-engineered and specifically
produced for geographical areas.Thesis (PhD)--University of Pretoria, 2012.
Microbiology and Plant Pathology
Unrestricted
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Pagano, Emanuele Vincenzo. "Space-time correlations of intermediate mass fragments emitted in Heavy ion reactions at Fermi energy by intensity interferometry studied with CHIMERA and perspectives." Doctoral thesis, Università di Catania, 2017. http://hdl.handle.net/10761/3984.
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In Heavy Ion Collisions (HIC) at Fermi energies (E/A between 10 MeV/nucleon and 100 MeV/nucleon) hot nuclear systems are produced and they may disassemble by a variety of dynamical and statistical mechanisms with vastly different time scales (neck emission, fission, multifragmentation, fusion-evaporation, ecc.). The study of the Space-Time properties of the emission pattern of the particles produced in the reactions represents one the most challenge topics of the modern investigation in nuclear physics. For this reason special geometrically flexible particle-particle correlation arrays are powerful tools to be used in coincidence mode with a 4pi detectors. Sensitivity to both space-time and spectroscopic properties of nuclear systems produced in HIC needs accurate measurements of both high angular and energy resolution over a large solid angle coverage. One of these arrays is FARCOS, presently under construction at the INFN Sezione di Catania and LNS. The FARCOS (Femtoscope ARray for COrrelations and Spectroscopy) consists of a number of twenty telescopes, each composed by two Double Sided Silicon Strip Detectors (DSSSD), of thickness 300 micron and 1500 micron, respectively, followed by four CsI(Tl) crystals of 6 cm of thickness read-out by silicon photodiodes. In this PhD thesis a report of the experimental characteristics of the FARCOS array is presented. In particular, tests with alpha sources and on-beams measurements coming from the recent experiment INKIISSY are discussed. A basic study of the particle-particle correlation function is also an important step of this large experimental effort in order to characterize the time scale of the reaction in different experimental configurations. In this work, the space-time sensitivity of the fragment-fragment Correlation Function to the emission of Intermediate Mass Fragments (the IMFs have atomic number between 3 and 25) has been investigated. In particular, IMF-IMF correlation function methods have been applied to 124Sn+64Ni at E/A= 35 MeV reverse kinematics reactions for the physics case of dynamical and statistical fission processes. The IMF-IMF correlation function shows good sensitivity in order to disentangle between dynamical and statistical processes. Some comparisons between data and theoretical simulations, are also discussed.
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Cherier, Dimitri. "CARACTERISATION BIOCHIMIQUE ET STRUCTURALE DE BACTERIOCINES CIBLANT LE METABOLISME DU PEPTIDOGLYCANE BACTERIEN, ALTERNATIVE POTENTIELLE AUX ANTIBIOTIQUES." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS529/document.
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L’émergence de bactéries multirésistantes aux antibiotiques est la conséquence de leur utilisation à mauvais escient au cours de ces dernières décennies. Ce phénomène constitue un problème de santé publique majeur, et face à cette urgence sanitaire, il est nécessaire de trouver rapidement de nouveaux agents antibactériens.Les colicines, au regard de leurs propriétés antimicrobiennes intrinsèques, constituent des candidats intéressants. Naturellement produites par E. coli dans le but de tuer des souches compétitrices de la même espèce ou d’espèces apparentées, elles exercent en général leur activité cytotoxique par le biais d’une activité ionophorique ou nucléasique. Parmi les nombreuses colicines connues à ce jour, la colicine M (ColM) est la seule à interférer avec la voie de biosynthèse du peptidoglycane, macromolécule essentielle et spécifique au monde bactérien. En effet, une fois dans le périplasme de E. coli, la ColM clive le lipide II, dernier précurseur de la voie de biosynthèse du peptidoglycane, conduisant de ce fait à la lyse bactérienne. Plusieurs homologues de la ColM ont été identifiés chez d’autres genres bactériens (Pseudomonas, Pectobacterium et Burkholderia) mais aucune cytotoxicité croisée n’a été mise en évidence à ce jour, d’où un spectre d’action restreint pour les membres de cette nouvelle famille d’enzymes antibactériennes.Ce travail traite de l’étude structurale et biochimique de la ColM et de certains de ses homologues. L’étude structurale de différents variants de la PaeM, homologue issu de P. aeruginosa, a permis d’identifier une molécule d’eau conservée au sein du site actif qui joue probablement un rôle central dans le mécanisme catalytique de cette famille d’enzyme. L’expression des homologues de la ColM issus de Pseudomonas et de Pectobacterium, directement dans le périplasme de E. coli, a permis de démontrer leur activité lytique, prouvant ainsi le grand potentiel de ces bactériocines en tant qu’alternatives aux antibiotiques. Enfin, la construction de plusieurs colicines chimères entre la ColM et ses homologues, capables de dégrader le lipide II in vitro et d’induire la lyse d’E. coli suite à leur expression périplasmique, ouvre la voie à de futurs espoirs thérapeutiquesThe misuse of antibiotics during the last decades led to the emergence of multidrug resistant pathogenic bacteria. This phenomenon constitutes a major public health issue. Given that urgency, the finding of new antibacterials in the short term is crucial.Colicins, due to their antimicrobials properties, constitute good candidates. They are protein toxins produced by E. coli to kill competitors belonging to the same or related species. In most cases, they exhibit their cytotoxic activity through an ionophoric or nucleasic activity. Among the twenty colicins known to date, colicin M (ColM) is the only one known to interfere with peptidoglycan biosynthesis. It develops its lethal activity in the E. coli periplasm, in three steps deeply linked to its structural organization in three domains. Once in the periplasm, ColM degrades the lipid II, i.e. the last precursor in the peptidoglycan biosynthesis pathway, in two products that cannot be reused, thereby leading to cell lysis. Several ColM homologues have been identified in other bacterial genera, such as Pseudomonas, Pectobacterium and Burkholderia, but no cross activity has been shown to date, explaining the narrow antibacterial spectrum displayed by the members of this new family of antibacterial enzymes.This work deals with the structural and biochemical study of ColM and some of its homologues. Structural studies on several variants of PaeM, the ColM homologue from P. aeruginosa, led to identify a conserved water molecule in the active site, probably playing a central role in the catalytic mechanism of this enzyme family. Moreover, expression of ColM homologues from Pseudomonas or Pectobacterium species directly in the E. coli periplasm showed that all these homologues were able to induce E. coli cell lysis, thus demonstrating the great potential of these bacteriocins as an alternative to antibiotics. Following these results, several chimera colicins were created between ColM and its homologues, which were shown to degrade lipid II in vitro and to induce E. coli cell lysis after their periplasmic expression, opening the way to future new therapeutic options
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Kemeth, Felix Peter [Verfasser], Katharina [Akademischer Betreuer] Krischer, Oliver [Gutachter] Junge, and Katharina [Gutachter] Krischer. "Symmetry Breaking in Networks of Globally Coupled Oscillators : From Clustering to Chimera States / Felix Peter Kemeth ; Gutachter: Oliver Junge, Katharina Krischer ; Betreuer: Katharina Krischer." München : Universitätsbibliothek der TU München, 2019. http://d-nb.info/1185069836/34.
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Harrison, Brown Meredith. "Whole body characterisation of bone marrow-derived cell kinetics: development of a syngeneic bone marrow chimera model for positron emission tomography with 18F-PBR111." Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/23639.
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Monitoring of cell transplantation in vivo is crucial to understanding how the progeny of stem cells contribute to or ameliorate disease. Although animal models enable researchers to understand the behaviour of specific cell types in great detail, they typically require invasive procedures or large numbers of animals in order to track sdisease progression or treatment efficacy over time. Positron emission tomography (PET) has emerged as a promising non-invasive method of tracking transplanted cells in preclinical research, as it enables researchers to track cells longitudinally over the lifespan of the host animal. Although existing reporter gene PET methodologies are under development, they are subject to a number of restrictions which limit their usefulness in preclinical research. These limitations include the need to transduce cells with reporter genes, which is inefficient and may lead to unwanted phenotypic changes in the cells of interest. Another major limitation for many applications is the inability of many reporter ligands to cross an intact blood-brain barrier. Described in this thesis is a novel methodology utilising the transplantation of wild-type bone marrow cells into mice lacking the Translocator Protein (18kDa; TSPO). The TSPO knockout mouse serves as a null-background model for transplantation of unmodified bone marrow cells which express endogenous TSPO. These TSPO-expressing cells are then targeted for PET imaging by a TSPO-specific radio-ligand, 18F-PBR111. PBR111 binds selectively to TSPO and can penetrate the intact blood-brain barrier, making it a promising approach for overcoming some of the limitations of reporter gene imaging. In brief, TSPO-knockout mice (and wild-type controls) were conditioned with a sub-lethal dose of gamma radiation and transplanted with nucleated bone marrow cells from C57BL/6 mice engineered to express green fluorescent protein (GFP). At various stages of engraftment ranging from 1 to 12 months post-transplant, mice were anaesthetised with 1-4% isoflurane, cannulated via the tail vein, and injected with 0.2nM of 18F-PBR111. Data was collected with an Inveon pre-clinical PET/CT camera for 50 minutes post-injection. Images were re-constructed into 20 time frames and were again re-constructed using a 3-dimensional ordered subset expectation maximization algorithm (3D-OSEM). From this, time activity curves (TACs) were extracted from regions of interest drawn on co-registered PET/CT images, corresponding to whole organs. TACs were then used to calculate standardised uptake values for each region of interest. Sections taken from collected tissues were later incubated with 125I-CLINDE in order to visualise receptor density in tissues independently of pharmacokinetic parameters associated with IV tracer injection. Sections were also stained with a monoclonal TSPO antibody in order to identify the TSPO-expressing cells at high spatial resolution. Engraftment rates in blood were assessed at 1, 3 and 6 months post transplantation using quantitative real-time PCR in order to determine whether haematopoietic reconstitution in TSPO knockout mice resembles its wild-type counterparts, which is important for establishing whether the results observed in vivo are physiologically ‘normal’ and therefore applicable to models of disease. Although engraftment rates were equivalent in wild-type and TSPO-/- background recipient mice 1 and 3 months post-transplantation, at 6 months engraftment rates in the TSPO-/- mice were significantly higher. Nonetheless, both genotypes displayed persistent engraftment of donor cells at a minimum of 6 months post-transplant, and observed up to 12 months post-transplant in the TSPO-/- recipients. This engraftment was detectable using both in vitro and in vivo methods (PET) in spleen tissue throughout the duration of the study, and in some tissues susceptible to inflammation such as lung and salivary gland at 6 months post-transplant. A pilot of longitudinal imaging also suggested this persistent migration of donor-derived cells could be detected up to at least half of the animal’s lifespan. Although some major successes in longitudinal monitoring of TSPO-expressing donor-derived cells was observed in this study, there were some notable exceptions, such as the bone marrow itself, susceptible to major spillover associated with free fluorine accumulating within bone, and regions marked by low level engraftment of cells, including brain, and lung parenchyma. For each tissue of interest, an in-depth discussion of the implications of the findings are presented, followed by an outline of the methodological challenges associated with whole-body imaging of rodents in this context. Overall, the model presented in this study has the potential for adaptation to a variety of models incorporating cell-based diseases or treatments, with the ability to track the accumulation of inflammatory cells in a variety of organs.
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Rao, Harita. "Metal containing peptides as specific DNA binders." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://hdl.handle.net/11858/00-1735-0000-0028-86AC-9.
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Namjoshi, Dhananjay Rajaram. "The role of apolipoprotein E in recovery from traumatic brain injury and development of CHIMERA : a novel closed-head impact model of engineered rotational acceleration." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52254.
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Traumatic brain injury (TBI) is a “silent epidemic” that currently lacks any effective treatment. While a major health care problem in itself, TBI also increases Alzheimer’s disease (AD) risk and leads to the deposition of neurofibrillary tangles and amyloid deposits similar to those found in AD. Agonists of Liver X receptors (LXRs), which regulate the expression of many genes involved in lipid homeostasis and inflammation, improve cognition and reduce neuropathology in AD mice. One pathway by which LXR agonists exert their beneficial effects is through ATP-binding cassette transporter A1-mediated lipid transport onto apolipoprotein E (apoE). In the first part of this thesis, I show that a short-term treatment with synthetic LXR agonist GW3965 improves post-injury outcomes in mice subjected to closed-head, mild, repetitive weight drop TBI (mrTBI). My results suggest that both apoE-dependent and apoE-independent pathways contribute to the ability of GW3965 to promote recovery from mrTBI. While many drugs have shown promising outcomes in preclinical TBI models, clinical drug trials for TBI so far have failed, suggesting that the translational potential of TBI models may require further improvement. As most human TBIs result from impact to an intact skull, closed head injury (CHI) rodent models are highly relevant. Traditional CHI models like weight drop however suffer from large experimental variability that may be due to poor control over biomechanical inputs. To address this caveat we developed a novel CHI model called CHIMERA (Closed-Head Impact Model of Engineered Rotational Acceleration) that fully integrates biomechanical, behavioral, and neuropathological analyses. CHIMERA is distinct from existing neurotrauma model systems in that it uses a completely non-surgical procedure to precisely deliver impacts of prescribed dynamic characteristics to a closed skull while enabling kinematic analysis of unconstrained head movement. Here I show that repeated TBI in mice using CHIMERA mimics many features of the human TBI including neurological, motor, and cognitive deficits along with persistent neuroinflammation and diffuse axonal injury, and increased endogenous tau phosphorylation up to 14 days with a reliable biomechanical response of the head. This makes CHIMERA well suited to investigate the pathophysiology of TBI and for drug development programs.Medicine, Faculty of
Graduate
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García, Soriano Daniela Azucena [Verfasser], and Petra [Akademischer Betreuer] Schwille. "Towards bottom-up reconstitution of a minimal division machinery : characterization of FtsZ chimera protein in different membrane systems / Daniela Azucena García Soriano ; Betreuer: Petra Schwille." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1179075803/34.
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Rouinsard, Alexandre. "Étude du caractère de panachure et de sa stabilité lors de la micropropagation de plantes monocotylédones." Thesis, Rennes, Agrocampus Ouest, 2021. http://www.theses.fr/2021NSARC156.
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La micropropagation des variétés à feuillage panaché (plusieurs couleurs sur une même feuille) peut générer des plantes non conformes au phénotype d’origine, particulièrement dans le cadre de plantes monocotylédones acaules. Or, par leur caractère fortement ornemental, ces variétés présentent un fort potentiel commercial. L’objectif était de déterminer les potentialités de micropropagation des monocotylédones panachées dans un contexte industriel et commercial, de définir la stabilité de leurs phénotypes, et de comprendre l’apparition des plantes hors-type. Les observations de coupes foliaires au microscope confocal à balayage laser sur les quatre cultivars étudiés Yucca gloriosa ‘Variegata’ (YgVAR), Yucca flaccida ‘Golden Sword’ (YflGS), Phormium tenax ‘Jessie’ (PtJE) et Cordyline australis ‘Pink Passion’ (CaPP) ont révélé que tous les cultivars étaient des chimères périclines, soit une panachure liée à un méristème stratifié avec plusieurs génotypes différents. En micropropagation,YgVAR a présenté des taux de conformité élevés, PtJE des taux modérés et CaPP de faibles taux. Des analyses histologiques sur les vitroplants ont mis en évidence des différences majeures dans le développement et le comportement de multiplication in vitro de ces trois espèces de l’ordre des Asparagales : YgVAR n'a développé que des méristèmes axillaires (AxM), PtJE principalement des AxM et quelques méristèmes adventifs (AdM), et CaPP à la fois des AxM et des AdM. Alors que les méristèmes axillaires préformés maintiennent la structure chimérique, les méristèmes adventifs la maintiennent peu. Donc la stabilité de la panachure de ces variétés dépend de leur propension à se propager par méristèmes adventifs. Des essais pour abaisser la dominance apicale et stimuler les méristèmes axillaires ont été menés, ainsi qu’une analyse du transcriptome des différents tissus panachés chez YflGS. Des protocoles de production industrielle adaptés à chaque cultivar sont finalement proposésThe micropropagation of variegated cultivars (several colors on the same leaf) can generate off-type plants to the original phenotype, particularly in the case of monocotyledonous plants. However, because of their highly ornamental character, these cultivars have a strong commercial potential. The objective were to determine the micropropagation potential of variegated monocots in an industrial and commercial context, to define the stability of their phenotypes, and to understand the origin of off-types. Observations of leaf sections under a confocal laser scanning microscope on the four studied cultivars: Yucca gloriosa 'Variegata' (YgVAR), Yucca flaccida 'Golden Sword' (YflGS), Phormium tenax 'Jessie' (PtJE), and Cordyline australis 'Pink Passion' (CaPP) revealed that all cultivars were periclinal chimeras, i.e., a variegation bound to stratified meristem with several different genotypes.In micropropagation, YgVAR showed high compliance rates, PtJE moderate rates and CaPP low rates. Histological analyses on vitroplants revealed major differences in the development and in vitro propagation behavior of these three species of the order Asparagales: YgVAR developed only axillary meristems (AxM), PtJE mainly AxM and some adventitious meristems (AdM), and CaPP both AxM and AdM. While preformed axillary meristems maintain the chimeric structure, adventitious meristems maintain little. Thus, the variegation stability of these chimeras depends on their propensity to propagate by adventitious meristems. Trials to lower apical dominance and stimulate axillary meristems were conducted, as well as transcriptome analysis of different variegated tissues in YflGS. Industrial production protocols adapted to each cultivar are finally proposed
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Ellena, Rachel A. "Antimicrobial and lipid binding properties of the C-terminal domain of apolipoprotein A-I determined using a novel apolipophorin III/apolipoprotein A-I (179-243) chimera." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10144827.
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Apolipoprotein A-I (apoA-I) is an exchangeable apolipoprotein that constitutes the major protein component of high density cholesterol. ApoA-I is a two-domain protein comprising an N-terminal helix bundle and a less-structured C-terminal domain in the lipid-free state. In the present study, the contribution of the C-terminal domain to the lipid binding and antimicrobial activity of apoA-I was investigated using a chimeric construct in which the C-terminal domain of apoA-I (179-243) was attached to an insect apolipoprotein, Locusta migratoria apolipophorin III (apoLp-III), bearing cysteine substitutions for residues 20 and 149. Circular dichroism results were consistent with the addition of a poorly structured domain to apoLp-III and revealed the apoLp-III helix bundle was successfully closed under oxidizing conditions. Electrophoresis, fluorescence spectroscopy and an in vitro study using macrophage cells revealed that the C-terminal domain in itself was insufficient for efficient binding to lipid, lipopolysaccharide and phosphatidylglycerol vesicles. These results suggest the underlying mechanisms governing these interactions are potentiated by cooperativity between the N- and C-terminal domains of apoA-I.
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Grieger, Patrick. "Untersuchungen zur Züchtung variegater Pelargonium x zonale-Hybriden auf tetraploider Stufe." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2007. http://dx.doi.org/10.18452/15673.
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Die vorliegende Arbeit befasst sich mit züchtungsmethodischen Untersuchungen zur Schaffung blattvariegater Pelargonium x zonale-Hybriden auf tetraploidem Leistungsstand. Basierend auf dem Wirkstoff Trifluralin konnte eine effektive Behandlungsvariante zur somatischen Polyploidisierung periklinalchimärischer Pelargonium x zonale-Klone etabliert werden. Unter Ausnutzung biparentaler Erbgänge wurden fünf ausgewählte Plasmotypen an das Leistungsniveau moderner Sortimente herangeführt. Daneben erbrachten Kreuzungen innerhalb der Sektion Ciconium hybridvariegate F1-Pflanzen. Die Möglichkeit der Ausnutzung von Kern-Plasma-Wechselwirkungen in der Pelargonienzüchtung wird diskutiert. Im Hinblick auf den Aufbau eines Protoplastenregenerationssystems konnten Zellsuspensionskulturen etabliert werden. Im Anschluss an enzymatische Verdauungen wurde die Regeneration von Kallus beobachtet. Variegate Pflanzen aus Mutationsversuchen mit NMH (Nitroso-Methyl-Harnstoff), einer weiteren experimentellen Variante, erwiesen sich als steril, so dass eine weiterführende Züchtungsarbeit auf diesem Weg bisher noch nicht möglich warThe study analyzes breeding schemes concerning the development of variegated tetraploid Pelargonium x zonale-hybrids (Pelargonium x hortorum). With a focus on practical relevance breeding methods for periclinal chimeric leaf patterns are discussed. Trifluralin-induced tetraploid Pelargonium x zonale-hybrids were successfully crossed with modern cultivars. Via biparental mode of inheritance five defined plasmotypes were transfered to the karyological background of current high-performance Pelargonium series. In a crossing-program within the section Ciconium hybrid-variegation was detected. The possibility of using nucleo-plasmatic interactions in developing new Pelargonium cultivars is discussed. First steps concerning a biotechnological approach to create variegated plants included the establishment of cell-suspension-cultures as the base for a protoplast regeneration system. Following the enzymatic digestion of Pelargonium-liquid cultures up to now, callus regeneration was achieved. Variegated plants resulting from mutagenic treatments with NMU (Nitroso-methylurea) proved to be sterile.
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Forman, Daron. "Viral Abrogation of Stem Cell Transplantation Tolerance Causes Graft Rejection and Host Death by Different Mechanisms: A Dissertation." eScholarship@UMMS, 2002. https://escholarship.umassmed.edu/gsbs_diss/72.
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Tolerance-based stem cell transplantation using sub-lethal conditioning is being considered for the treatment of human disease, but safety and efficacy remain to be established. In order to study these two issues, we first established that mouse bone marrow recipients treated with sub-lethal irradiation plus transient blockade of the CD40-CD154 costimulatory pathway develop permanent hematopoietic chimerism across allogeneic barriers. Our conditioning regimen of 6 Gy irradiation, a short course of anti-CD154 mAb and 25 million fully allogeneic BALB/c bone marrow cells consistently produced long-term, stable, and multilineage chimerism in C57BL/6 recipients. Furthermore, chimeric mice displayed donor-specific transplantation tolerance, as BALB/c skin allografts were permanently accepted while third-party CBA/JCr skin allografts were promptly rejected. We next determined both the safety and efficacy of this protocol by infecting chimeric mice with lymphocytic choriomeningitis virus (LCMV) either at the time of transplantation or at several time points afterwards. Infection with LCMV at the time of transplantation prevented engraftment of allogeneic, but not syngeneic, bone marrow in similarly treated mice. Surprisingly, infected allograft recipients also failed to clear the virus and died. Post-mortem study revealed hypoplastic bone marrow and spleens. Hypoplasia and death in these mice required the combination of 6 Gy irradiation, LCMV infection on the day of transplantation, and an allogeneic bone marrow transplant but did not require the presence of anti-CDl54 mAb. Allochimeric mice infected with LCMV 15 days after transplantation were able to survive and maintain their bone marrow graft, indicating that the deleterious effects of LCMV infection on host and graft survival are confined to a narrow window of time during the tolerization and transplantation process. The final section of this thesis studied the mechanisms of graft rejection and death in sublethally irradiated recipients of allogeneic bone marrow and infection with LCMV at the time of bone marrow transplantation. Infection of interferon-α/β receptor knockout mice at the time of transplantation prevented the engraftment of allogeneic bone marrow, but the mice survived. Therefore, IFN-αβ is involved in the development of marrow hypoplasia and death, whereas a second mechanism is involved in blocking the development of chimerism in these mice. Through the use of depleting mAb's and knockout mice we demonstrate that three types of recipients survived and became chimeric after being given sublethal irradiation, anti-CD154 mAb, an allogeneic bone marrow transplant and a day 0 LCMV infection: mice depleted of CD8+ T cells, CD8 knockout mice, and TCR-αβ knockout mice. Our data indicate that the mediator of bone marrow allograft destruction in LCMV-infected mice treated with costimulatory blockade is a radioresistant CD8+ NK1.1- TCRαβ+ T cell. We conclude that a non-cytopathic viral infection at the time of transplantation can prevent engraftment of allogeneic bone marrow and result in the death of sub-lethally irradiated mice treated with costimulation blockade. The abrogation of allogeneic bone marrow engraftment is mediated by a population of CD8+ NK1.1- TCRαβ+ T cells and the mediator of hypoplasia and death is viral induction of IFN-αβ.
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Plaschil, Sylvia. "Vergleichende Untersuchungen zur histogenetisch bedingten Sternmusterbildung in der Petalenfärbung bei Camellia L., Myosotis L., Pelargonium L. Herit. ex Ait., Phlox L., Rhododendron L., Saintpaulia H. Wendl., Verbena L." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 1997. http://dx.doi.org/10.18452/14306.
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Histogenetisch bedingte Sternmusterungen an Petalen treten in verschiedenen Pflanzengattungen auf und konnten bei Camellia, Pelargonium, Phlox, Rhododendron, Saintpaulia und Verbena nachgewiesen werden, sie sind aber auch bei Myosotis und Petunia bekannt. Die Sternmusterungen entstehen bei den untersuchten Sorten durch Anthocyandefektmutation in einer bestimmten Sproßscheitelschicht und den abstammenden Geweben, in Abhängigkeit von der gewebespezifischen Farbstoffbildung im Blütenblatt, dem Wirken der Partnerinduktion von anthocyanintaktem auf anthocyandefektes Gewebe (Induktion der Anthocyansynthese) und der L1-Beteiligung an der Mesophyllbildung des Blütenblattrandes. Fünf unterschiedliche Typen der histogenetisch bedingten Sternmusterbildung in der Petalenfärbung unter Berücksichtigung dieser Charakteristika konnten gefunden werden.Histogenetically determined pinwheel patterns in petals exist in various genera of plants. Such patterns have been proved in Camellia, Pelargonium, Phlox, Rhododendron, Saintpaulia and Verbena, and are also known in Myosotis and Petunia. Pinwheel patterns occur by mutation in a defined layer of the apex and ist originated tissues. Its intensity is affected by presence of pigmentation in specific tissues of the petal and the existance and level of partner- induction (induction of anthocyanin synthesis from anthocyan-intact to anthocyan-defect tissue), and the participation of L1 (layer one of the apex) on the formation of mesophyll in the margin of the petal. Five different types of the histogenetically determined formation of pinwheel patterns were found according to the above mentioned conditions. In addtion, some other types can exist when more than two layers of the apex and their derived tissues form the petals (perhaps in Camellia) and layer 2 and 3 are different in their genotypes.
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Wong-Deyrup, Siu Wah. "DNA sequence selectivity and kinetic properties of de novo designed metalloprotein dimers." Diss., University of Iowa, 2007. http://ir.uiowa.edu/etd/185.
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Uzunel, Mehmet. "The methodology and significance of minimal residual disease detection after allogeneic stem cell transplantation /." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-619-7.
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INTROINI, BIANCA. "DESIGN OF CHIMERIC ION CHANNELS TO MONITOR CAMP-INDUCED CONFORMATIONAL CHANGES AND DYNAMICS." Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/719688.
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Hyperpolarization-activated cyclic nucleotide-gated (HCN1-4) channels are the molecular correlate of Ih (or If) current, which plays a key role in the control of neuronal and cardiac rhythmicity. HCNs are activated by the hyperpolarization of the membrane potential and further regulated by the direct binding of cyclic AMP (cAMP) to the cytoplasmic Cyclic Nucleotide Binding Domain (CNBD). cAMP binding determines the removal of the autoinhibitory action exerted by the CNBD on the pore opening and causes conformational changes that propagate from the CNBD to the pore through the C-linker, increasing channel open probability and speeding activation kinetics.
cAMP modulation of HCN controls rhythmicity and excitability at cardiac and neuronal level and pain perception. Thus, in order to understand several physiological functions, as well as diseases affecting both the cardiac and neuronal system, a detailed description of the cAMP-induced conformational changes is required. Moreover, functional studies indicate that cAMP binding to the CNBD induces the transition of the C-terminal domains, from dimer of dimer to tetramer and that this transition is driven by the movements of the C-linker.
The goal of this work is to describe the propagation of the movements through the C-linker to the pore. To this end, I have applied spectroscopic techniques, such as Electron Paramagnetic Resonance (EPR) and Double Electron-Electron Resonance (DEER) to study dynamic changes in the structure of the purified and labelled protein. First, I constructed a chimeric channel by fusing the C-linker/CNBD of human HCN4 to the prokaryotic pore domain of KcsA. This protein has the advantage that can be produced and easily purified in E. coli. Isothermal Titration Calorimetry (ITC) and Differential Scanning Calorimetry (DSC) measurements demonstrated that the purified chimera is able to bind cAMP. Particularly, ITC gave a Kd value of 1.7 μM, which agrees with the one previously published for the isolated C-linker/CNBD fragment of HCN4. Moreover, the rescue of a K+-uptake deficient E. coli strain demonstrated that the chimeric channel is able to conduct a K+ ions flow.
EPR-DEER experiments performed on the chimera revealed that the binding of cAMP to the CNBD domain causes clear conformational changes in the C-terminal region, which transits from a dimer of dimers conformation to a 4-fold symmetrical gating ring. These data confirm previous biochemical and functional indication obtained on the full-length channel and give further details on the direction and the extent of subunit displacement occurring during the conformational transition. The transition of the channel from a dimer of dimer to a tetrameric configuration of the cytosolic domain might reflect a pre-conditioning state for cAMP action on channel gating and partly explains the agonist activity exerted by cAMP on channel kinetics and open probability.