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The Role of IRAK-1 in the Regulation of Free Radicals and Oxidative Stress during EndotoxemiaSingh, Neeraj 30 July 2010 (has links)
Oxidative stress plays a vital role in the pathogenesis of many chronic and acute inflammatory diseases. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are two key mediators that are known to induce cellular and tissue oxidative stress. The generation of ROS and RNS is mediated by innate immune signaling processes. Lipopolysaccharide (LPS), a major inflammatory signal, is known to be a potent inducer of ROS/RNS. Thus, strategies that may block LPS-mediated generation of free radicals may hold promise in treating various inflammatory disease processes. However, the molecular mechanisms underlying LPS-mediated ROS/RNS production are not fully defined. Interleukin-1 Receptor associated kinase (IRAK-1), an intracellular kinase downstream of Toll-like Receptor 4 (TLR4) has been shown to contribute to the inflammatory cascade associated with LPS-TLR4 signaling pathway. However, its role in ROS production has not been defined. Therefore, we tested the hypothesis that IRAK-1 plays an important role in regulating ROS/RNS production. Both in vitro and in vivo studies were conducted to investigate the role of IRAK-1 in modulating free radicals as well as oxidative stress. In vitro studies demonstrate that IRAK-1 is a critical molecule involved in the induction of ROS/RNS. IRAK-1 deletion ablated free radical production following LPS challenge in a variety of cell types including macrophages, fibroblasts and microglia. Mechanistically, we observed that IRAK-1 is required for optimal expression and activity of NADPH oxidase subunits and iNOS. IRAK-1 deletion reduced LPS-triggered p47phox membrane translocation, suppressed NOX-1 expression and protein levels as well as hampered Rac1 activation. On the other hand, IRAK-1 deletion sustained antioxidative enzyme activity and levels in IRAK-1-/- macrophages and fibroblasts. In terms of the in vivo physiological consequences, IRAK-1-/- mice exhibited attenuated lipid peroxidation in vital organs, attenuated histopathological lesions in liver and kidney, and reduced endotoxemia-associated mortality. Taken together, IRAK-1 may, at least in part, serve as an important therapeutic target in the treatment of various inflammatory disease processes. / Ph. D.
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All-AmericanWilson, Leroy Lamar 25 May 2010 (has links)
All-American interrogates J. Hector St. John de Crevecoeur’s definition of “American" in the 1782 text, Letters from an American Farmer, which inspired the Eurocentric, sexist and heterosexist ideals girding the notion of what is now called the “American Dream." Mainstream media project narratives that suggest that the ideals in Crevecoeur’s epistles have been fully extended beyond his narrow scope in the Obama era. All-American, however, offers poetry that illuminates modern and contemporary instances in urban and rural settings of racism, colorism, gender bias, ability discrimination and homophobia thwarting this idealistic worldview. Its formal and free verse explores the journey of four generations of one family as members grapple with discrimination, disability and disease and interrogates the heteronormativity and racism that girds the faith to which they cling. Whereas many contemporary poets eschew the confessional in storytelling, All-American employs it unabashedly. Moreover, All-American is interested in language poetry, not only that which plays with various Englishes but also with the languages that color them, that percolate under the surface. It aims to make music of these dialogical languages, these inexorable narratives. It lets the dead and dying tell their stories, which are no less American, though they are unpopular in an America racing to rid itself of past shame. All-American faces the shameful things Americans can do to one another and celebrates humans’ innate will to thrive, love and die with dignity—with hopes of inspiring dialogue and healing that will make American ideals more accessible to those on the periphery. / Master of Fine Arts
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Automated Assessment of Student-written Tests Based on Defect-detection CapabilityShams, Zalia 05 May 2015 (has links)
Software testing is important, but judging whether a set of software tests is effective is difficult. This problem also appears in the classroom as educators more frequently include software testing activities in programming assignments. The most common measures used to assess student-written software tests are coverage criteria—tracking how much of the student’s code (in terms of statements, or branches) is exercised by the corresponding tests. However, coverage criteria have limitations and sometimes overestimate the true quality of the tests. This dissertation investigates alternative measures of test quality based on how many defects the tests can detect either from code written by other students—all-pairs execution—or from artificially injected changes—mutation analysis. We also investigate a new potential measure called checked code coverage that calculates coverage from the dynamic backward slices of test oracles, i.e. all statements that contribute to the checked result of any test. Adoption of these alternative approaches in automated classroom grading systems require overcoming a number of technical challenges. This research addresses these challenges and experimentally compares different methods in terms of how well they predict defect-detection capabilities of student-written tests when run against over 36,500 known, authentic, human-written errors. For data collection, we use CS2 assignments and evaluate students’ tests with 10 different measures—all-pairs execution, mutation testing with four different sets of mutation operators, checked code coverage, and four coverage criteria. Experimental results encompassing 1,971,073 test runs show that all-pairs execution is the most accurate predictor of the underlying defect-detection capability of a test suite. The second best predictor is mutation analysis with the statement deletion operator. Further, no strong correlation was found between defect-detection capability and coverage measures. / Ph. D.
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Activity patterns at Cape Hatteras National Seashore: an analysis of off-road vehicle and pedestrian users among visitors and residentsPafford, Bradley Vance January 1979 (has links)
The purpose of this study was to describe the use of Cape Hatteras National Seashore from visitors and local residents of the Outer Banks, and to explore the differences in use for off-road vehicle (ORV) users and pedestrians within each of these user groups. During the summer of 1978, 598 visitors were randomly sampled at Cape Hatteras and sent mail-back questionnaires. Eighty percent of the 598 eligible respondents returned the questionnaire, providing half the data for this study. Four hundred thirty-two local residents were systematically sampled from phone books of residents of the Outer Banks of North Carolina, and sent mail-back questionnaires in the winter of 1978. Sixty percent of the 342 eligible respondents returned the questionnaire, providing the other half of the data used in this study.
It was found that the ORV and pedestrian visitors used the seashore quite differently, visiting many locations in different proportions and participating in activities differently. Seasonal and experience-related differences were present. Local resident ORV owners and non-ORV owners were different in their use of Cape Hatteras for recreational purposes as well. The ORV owner was a much more active user of the seashore than the non-ORV owner.
Many implications for planning and management of Cape Hatteras are suggested. Based upon the results obtained, no substantive conclusions can be made about whether user conflict exists between ORV and non-ORV users. / Master of Science
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The All-Volunteer Force and Presidential Use of Military ForceNasca, David Stephen 16 October 2019 (has links)
The creation of the All-Volunteer Force (AVF) in 1973 allowed U.S. presidents to deploy American military power in times and places of their own choosing with fewer concerns that the electorate would turn against their leadership. A reaction to the trauma of the Vietnam War, the AVF did away with conscription and instead relied on volunteers to serve and fight in U.S. military operations. The AVF's ranks were mostly filled with those willing to deploy and fight for their country, without the U.S. having to rely on conscription. When U.S. presidents had to use the AVF to fight in conflicts, they could expect to enjoy a higher degree of public support than those presidents who led the U.S. military during the Korean and Vietnam wars.
Drawing from casualty, financial, and public opinion statistics from 1949 through 2016, this thesis argues that with the adoption of the AVF in 1973 U.S. presidents have been better able to deploy the AVF in combat with less resistance from the American people. It examines the circumstances behind the creation of the AVF, looking second, at the deployment of the AVF from the Gulf War to the Global War on Terror to determine if U.S. presidents enjoyed popular support and were encouraged to rely on military force as the primary option in foreign policy. Finally, the study compares casualties, financial costs, and public support for conflicts relying on conscripted forces to those depending on the AVF to examine if U.S. presidents were better able to involve the U.S. in military conflicts of questionable interest with fewer worries about organized anti-war movements.
The conclusions of my research revealed that my hypothesis was wrong in that the creation of the AVF did not mean the U.S. presidency enjoyed a higher degree of support during conflicts. With the exception of the Gulf War, presidential approval when using the AVF was less than 50% in every conflict by the time military operations ended. The majority of conflicts disclosed that public approval and disapproval was based on casualties, regardless if service members were draftees or volunteers, as well as financial costs. For Korea and Vietnam, high casualties and financial costs resulted in approval levels dropping quickly while Afghanistan and Iraq took longer because casualties and spending did not escalate as quickly. As a result, I discovered that public approval and disapproval levels influenced political change. In the case of Korea, Vietnam, Afghanistan, and Iraq, it forewarned changes in political leadership while conflicts such as Somalia, Bosnia, and Kosovo were kept short and inexpensive to prevent political opposition from organizing against the presidency. / Master of Arts / This thesis explores presidential use of military power from 1949 through 2016, examining the impact of the All-Volunteer Force (AVF). The research looks at whether the AVF is associated with U.S. presidents having more public support when using military power in various parts of the world. Prior to the AVF, conscription helped meet the personnel needs of the U.S. military; however, this system became problematic when it was used to fight conflicts that became unpopular with the American public. Not only were the loyalty and performance of the conscripts often questionable, the public also frequently placed pressure on presidents to curb U.S. military operations overseas. This thesis examines the emergence of the AVF, how presidents have deployed it, and the differences in American public support, casualties, and financial costs between the use of the conscript force and the AVF under U.S. presidents in major military conflicts from 1949 through 2016. The findings revealed very little difference in presidential use of military power whether employing the conscript force or the AVF. An examination of the nation’s major conflicts since 1949 suggests that public support was based on U.S. lives lost and monies spent, with higher levels of these categories associated with lower presidential approval and higher disapproval ratings. In conclusion, although the AVF was created to end the need for the draft to support national defense, the American public remained concerned about how U.S. presidents used the military overseas especially when engaged in distant open-ended conflicts.
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Selective Deposition of Copper Traces onto Additively Manufactured All-Aromatic Polyimides via Laser Induced Graphene to Enable Conformal Printed ElectronicsWotton, Heather Dawn 03 April 2024 (has links)
The hybridization of direct write (DW) and additive manufacturing (AM) technologies to create additively manufactured electronics (AME) has enabled the integration of electrical functionality to form multifunctional AM components. Current work in AME has demonstrated the integration of conductive traces into and onto geometries and form factors that are not possible through traditional electronics packaging processes. This has largely been accomplished by using AM and DW technology to deposit conductive inks to form interconnects on the surface of AM substrates or within multimaterial AM geometries. However, the requisite thermal post-processing and high resistivity of the conductive inks and the limitations in thermal and dielectric performance of printable substrates commonly used in AME restrict the capabilities of these parts.
This thesis proposes an alternative process for the conformal deposition of low resistivity traces on additively manufactured all-aromatic polyimides (AM-PI) without the use of conductive inks. This is accomplished through the selective patterning of laser induced graphene (LIG), a porous 3D graphene fabricated via laser irradiation, onto the AM-PI. While the resultant LIG is conductive, its resistivity is further reduced by the electrodeposition of copper (Cu-LIG).
In this thesis, the synthesis of LIG on AM-PI, thermally post processed to 240℃, 300℃, and 450℃, is demonstrated and characterized through sheet resistance measurements and Raman spectroscopy. AM-PI post-processed to 300℃ demonstrated the lowest resistivity LIG formation (13.8 Ω/square). The resistivity of Cu-LIG is compared to an industry standard silver ink (Micromax CB028) used in direct write hybrid manufacturing applications. Cu-LIG was found to have a measured resistivity (1.39e-7 Ω·m), two orders of magnitude lower than the measured resistivity of the CB028 silver ink (1.62e-5 Ω·m). Additionally, the current capacity of the Cu-LIG was demonstrated and Joule heating of the material was observed via IR thermography. Cu-LIG demonstrated no failure of conductive trace or substrate under 5A of current for 2 minutes, heating to a maximum recorded temperature of 76.3℃.
Several multifunctional components were fabricated as case studies to further validate the process. Several small passive electronic devices (e.g., a heater and an interdigitated capacitor) are fabricated to demonstrate selective deposition of complex copper traces. The fabrication of an Archimedes spiral on a hemispherical substrate via Cu-LIG is completed to demonstrate the ability to use the process to fabricate conformal conductive traces. An LED circuit is fabricated on a face-center cubic AM-PI lattice which demonstrates multi-planar fabrication on geometrically complex 3D printed substrates. / Master of Science / The hybridization of direct write (DW) and additive manufacturing (AM) technologies to create additively manufactured electronics (AME) has enabled the fabrication of AM components which have electronic functionality. Current work in AME has demonstrated the integration of conductive traces into and onto geometries and form factors that are not possible through traditional electronics packaging processes. This has largely been accomplished through the deposition of conductive inks to form interconnects on the surface of AM substrates or within multimaterial AM geometries. However, these conductive inks require thermal post-processing temperatures which exceed the thermal performance of common AM substrates. The dielectric performance of AM substrates is also restrictive to the capabilities of these parts.
This thesis proposes an alternative process for the conformal deposition of low resistivity traces on high performance additively manufactured all-aromatic polyimides (AM-PI) without the use of conductive inks. This is accomplished through the selective patterning of laser induced graphene (LIG), a porous 3D graphene fabricated via laser irradiation, onto the AM-PI. While the resultant LIG is conductive, its resistivity is further reduced by the electrodeposition of copper (Cu-LIG).
In this thesis, the synthesis of LIG on AM-PI, thermally post processed to 240℃, 300℃, and 450℃, is demonstrated and characterized through sheet resistance measurements and Raman spectroscopy. AM-PI post-processed to 300℃ demonstrated the lowest sheet resistance LIG formation (13.8 Ω/square). The resistivity of Cu-LIG is compared to an industry standard silver ink (Micromax CB028) used in direct write hybrid manufacturing applications. Cu-LIG was found to have a measured resistivity (1.39e-7 Ω·m), two orders of magnitude lower than the measured resistivity of the CB028 silver ink (1.62e-5 Ω·m). Additionally, the thermal performance and current capacity of the Cu-LIG was demonstrated by observing resistive heating of the material under current load via IR thermography. Cu-LIG demonstrated no failure of conductive trace or substrate under 5A of current for 2 minutes, heating to a maximum recorded temperature of 76.3℃.
Several multifunctional components were fabricated as case studies to further validate the process. A heater and an interdigitated capacitor are fabricated to demonstrate selective deposition of complex copper traces. The fabrication of an Archimedes spiral on a dome via Cu-LIG is completed to demonstrate the ability to use the process to fabricate conformal conductive traces. An LED circuit is fabricated on an AM-PI lattice which demonstrates multi-planar fabrication on geometrically complex 3D printed substrates.
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Treatment of Systemic Lupus Erythematosus by Nutrition and Dendritic Cell TargetingLiao, Xiaofeng 10 August 2017 (has links)
Systemic lupus erythematosus (SLE) is an autoimmune disease involving the inflammatory damages of multiple organs. Lupus nephritis (LN) as the manifestation in the kidney occurs in more than 50% of SLE patients and is a major cause of morbidity and mortality. Current treatments consist of immunosuppressants that always lead to compromised immune responses with increased risks of infections as the major side effect. To minimize this side effect, it is crucial to develop new treatments that are more natural and specific.
Vitamin A, particularly in the form of its functional metabolite, retinoic acid, has shown some beneficial effects against LN in both lupus-prone mouse models and clinical cases. However, a more systemic evaluation of vitamin A treatment in lupus had not been investigated. In our study, we found paradoxical effects of all-trans-retinoic acid (tRA) on lupus-like disease in MRL/lpr lupus-prone mice. Starting at 6 weeks old when the inflammatory environment had been established in MRL/lpr mice, tRA administration reduced immune cell numbers in the secondary lymphoid organs and improved glomerulonephritis. However, circulating autoantibodies and inflammation in renal tubulointerstitium and other organs were increased. The detrimental effects of tRA were not present in MRL control mice, which didn't have an established inflammatory environment at 6 weeks old as shown in MRL/lpr mice, suggesting that the pro-inflammatory effects of tRA are dependent on the pre-existing inflammatory environment. Therefore, to successfully apply vitamin A-based treatment, it is important to avoid the detrimental effects of tRA on lupus by identifying and then specifically eliminating the critical pro-inflammatory immune cell types in lupus. As treatments usually start after the onset of apparent symptoms in patients at the effector stage of autoimmune responses, targeting the inflammatory contributors at this stage appears to be more practical and critical.
Among different types of leukocytes, we chose to focus on dendritic cells (DCs), because they are highly diverse and critical in the immune responses as a bridge between the innate and adaptive immune systems. Plasmacytoid DCs (pDCs) as a candidate target have been demonstrated to be crucial for the initiation of lupus development by producing IFNα. However, we demonstrated that although pDCs produced a large amount of IFNα during disease initiation, those from late-stage lupus mice were found to be defective in producing IFNα, suggesting that pDC-targeted treatments should be performed at the initiation stage. This will depend on the progress in early diagnosis in the future. Besides pDCs, we identified a CD11c+ cell population absent at the early-stage but gradually accumulating at the late-stage in the kidneys of lupus mice. These cells have a phenotype of mature monocyte-derived DCs, with particularly high CX3CR1 expression on the surface. Consistent with their pathogenic cytokine profile, in vivo administration of anti-CX3CR1-saporin conjugates to dysfunction these cells in MRL/lpr mice significantly reduced proteinuria scores. Ex vivo activation of renal-infiltrating CD4+ T cells showed increased survival rate, proliferation and IFN-γ production of activated CD4+ T cells when they were cultured with these renal-infiltrating CD11c+ cells. These results suggest that the renal-infiltrating CD11c+ cells are pathogenic and promote inflammation in the kidney at the later effector stage of lupus by interacting with renal-infiltrating CD4+ T cells.
In conclusion, although vitamin A showed anti-inflammatory effects on reducing glomerulonephritis, its use in lupus treatment should be guarded due to the other potential pro-inflammatory effects induced by the pre-existing inflammatory environment. IFNα-producing pDCs and CX3CR1highCD11c+ monocyte-derived DCs could be specific therapeutic targets to reduce the established inflammation at the early stage and late stage of LN, respectively. Therefore, it is worthwhile to further investigate the comprehensive effects of combination therapy on lupus, with vitamin A administration and pDCs-specific depletion at the early stage, and CX3CR1highCD11c+ monocyte-derived DCs-specific depletion at the late stage. / Ph. D. / Systemic lupus erythematosus (SLE) is an autoimmune disease involving the inflammatory damages of multiple organs. Lupus nephritis (LN) as the manifestation in the kidney occurs in more than 50% of SLE patients and is a major cause of morbidity and mortality in this disease. Current treatments consist of immunosuppressants that always lead to compromised immune responses with increased risks of infections as the major side effect. To minimize this side effect, it is crucial to develop new treatments that are more natural and specific. My first project was to determine whether vitamin A as a supplement could ameliorate SLE. It turned out to be effective at attenuating LN, but at the same time the nutrient caused massive inflammation in other peripheral organs such as the brain and lungs. This suggests that we need to be cautious when recommending vitamin A supplementation to lupus patients. In order to identify more specific targets in the treatment of SLE, my second and third projects focused on dendritic cells (DCs) that are essential for lupus pathogenesis. I found that plasmacytoid DCs (pDCs), known to be pathogenic in SLE, were in fact defective at promoting inflammation at the late stage of disease, suggesting that pDCs might not be a good target of intervention. In contrast, monocyte-derived conventional DCs turned out to be highly pathogenic especially for the development of LN and could be a potential therapeutic target. Altogether, my investigations have increased our understanding of the pathogenesis of SLE.
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Trombone Shout: Instrumental Voices in the United House of Prayer for All PeopleChevan, Jesse Abel January 2024 (has links)
This dissertation is an ethnography of an African American sacred music tradition – the trombone worship bands of the United House of Prayer for All People (UHOP) – that examines the ways in which musical aesthetics mediate racial and economic marginality and religious authority. Musical worship featuring these “shout bands,” involves UHOP members in an embodied performance of religious discourse, including actualizing the boundaries of sanctified interiority, confirming the charismatic authority of the organization’s sacralized leader, and constituting the independence and sovereignty of the UHOP Kingdom. The project is animated by a central question: given continuities in repertoire, performance practice, and theology between UHOP shout bands and other Black gospel practices, why is musical worship at the UHOP organized around the trombone rather than the human voice? The dissertation answers this question dialectically by showing how shout band music-making offers solutions to the ethical and theological issues members face, while UHOP theological discourse capitalizes on the sensory affordances of musical practice.
The opening chapter introduces the role of the shout band in the context of UHOP worship services, framing musical practice as the enactment of sacred divisions of space and subjectivity. This chapter also depicts the feedback loop between worship practice and scriptural interpretation by introducing UHOP-specific idioms of Biblical literalism and re-enactment.
Chapter two dilates on the connections between musical microsocialities and forms of authority through an analysis of the “figure of call-and-response” as a medium for the bishop’s charismatic authority. In the final chapter, I survey a variety of UHOP state-mimetic forms – that is, forms appropriated from the symbolic repertoire of the United States government – as points of entry into the ways that members actualize a shared notion of “freedom.”
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Multi-Core Fiber and Optical Supersymmetry: Theory and ApplicationsMacho Ortiz, Andrés 02 September 2019 (has links)
[ES] A día de hoy, las redes de comunicaciones de fibra óptica están alcanzando su capacidad límite debido al rápido crecimiento de la demanda de datos en la última década, generado por el auge de los teléfonos inteligentes, las tabletas, las redes sociales, la provisión de servicios en la nube, las transmisiones en streaming y las comunicaciones máquina-a-máquina. Con el fin de solventar dicho problema, se ha propuesto incrementar la capacidad límite de las redes ópticas mediante el reemplazo de la fibra óptica clásica por la fibra óptica multinúcleo (MCF, acrónimo en inglés de multi-core fiber), la cual es capaz de integrar la capacidad de varias fibras ópticas clásicas en su estructura ocupando prácticamente la misma sección transversal que éstas.
Sin embargo, explotar todo el potencial de una fibra MCF requiere entender en profundidad los fenómenos electromagnéticos que aparecen en este tipo de fibras cuando guiamos luz a travésde ellas. Así pues, en la primera parte de la tesis se analizan teóricamente estos fenómenos electromagnéticos y, posteriormente, se estudia la viabilidad de la tecnología MCF en distintos tipos de redes ópticas de transporte, específicamente, en aquellas que hacen uso de transmisiones radio-sobre-fibra. Estos resultados pueden ser de gran utilidad para las futuras generaciones móviles 5G y Beyond-5G en las próximas décadas.
Adicionalmente, con el fin de expandir las funcionalidades básicas de las fibras MCF, esta tesis explora nuevas estrategias de diseño de las mismas utilizando la analogía existente entre las ecuaciones que rigen la mecánica cuántica y el electromagnetismo. Con esta idea en mente, en la segunda parte de la tesis se propone diseñar una nueva clase de fibras MCF usando las matemáticas de la supersimetría, surgida en el seno de la teoría de cuerdas y de la teoría cuántica de campos como un marco teórico de trabajo que permite unificar las interacciones fundamentales de la naturaleza (la nuclear fuerte, la nuclear débil, el electromagnetismo y la gravedad). Girando en torno a esta idea surgen las fibras MCF supersimétricas, las cuales nos permiten procesar la información de los usuarios durante la propia propagación de la luz a través de ellas, reduciendo así la complejidad del procesado de datos del usuario en recepción.
Finalmente, esta tesis se completa introduciendo un cambio de paradigma que permite diseñar dispositivos fotónicos disruptivos. Demostramos que la supersimetría de mecánica cuántica no relativista, propuesta como una serie de transformaciones matemáticas restringidas al dominio espacial, se puede extender también al dominio del tiempo, al menos dentro del marco de trabajo de la fotónica. Como resultado de nuestras investigaciones, demostramos que la supersimetría temporal puede convertirse en una plataforma prometedora para la fotónica integrada ya que nos permite diseñar nuevos dispositivos ópticos versátiles y ultra-compactos que pueden jugar un papel clave en los procesadores del futuro.
Asimismo, con el fin de hacer los resultados principales de esta tesis doctoral lo más generales posibles, se detalla cómo poder extrapolarlos a otros campos de la física como acústica y mecánica cuántica. / [CA] Avui en dia, les xarxes de comunicacions de fibra òptica estan aconseguint la seua capacitat límit a causa del ràpid creixement de la demanda de dades duante l'última dècada, generat per l'auge dels telèfons intel·ligents, les tablets, les xarxes socials, la provisió de servicis en la núvol, les transmissions en streaming i les comunicacions màquina-a-màquina. Per a resoldre el dit problema, s'ha proposat incrementar la capacitat límit de les xarxes òptiques per mitjà del reemplaçament de la fibra òptica clàssica per la fibra òptica multinúcleo (MCF, acrònim en anglés de multi-core fiber), la qual és capaç d'integrar la capacitat de diverses fibres òptiques clàssiques en la seua estructura ocupant pràcticament la mateixa secció transversal que estes.
Tanmateix, explotar tot el potencial d'una fibra MCF requereix entendre en profunditat els fenòmens electromagnètics que apareixen en aquestes fibres quan guiem llum a través d'elles. Així, doncs, en la primera part de la tesi analitzem teòricament aquests fenòmens electromagnètics i, posteriorment, estudiem la viabilitat de la tecnologia MCF en distints tipus de xarxes òptiques de transport, específicament, en aquelles que fan ús de transmissions ràdio-sobre-fibra. Estos resultats poden ser de gran utilitat per a les futures generacions mòbils 5G i Beyond-5G en les pròximes dècades.
Addicionalment, a fi d'expandir les funcionalitats bàsiques de les fibres MCF, esta tesi explora noves estratègies de disseny de les mateixes utilitzant l'analogia existent entre les equacions que regixen la mecànica quàntica i l'electromagnetisme. Amb aquesta idea en ment, en la segona part de la tesi proposem dissenyar una nova classe de fibres MCF usant les matemàtiques de la supersimetria, sorgida en el si de la teoria de cordes i de la teoria quàntica de camps com un marc teòric de treball que permet unificar les interaccions fonamentals de la natura (la nuclear forta, la nuclear feble, l'electromagnetisme i la gravetat). Al voltant d'aquesta idea sorgeixen les fibres MCF supersimètriques, les quals ens permeten processar la informació dels usuaris durant la pròpia propagació de la llum a través d'elles, reduint així la complexitat del processament de dades de l'usuari a recepció.
Finalment, esta tesi es completa introduint un canvi de paradigma que permet dissenyar dispositius fotónicos disruptius. Demostrem que la supersimetria de mecànica quàntica no relativista, proposta com una sèrie de transformacions matemàtiques restringides al domini espacial, es pot estendre també al domini del temps, almenys dins del marc de treball de la fotónica. Com resultat de les nostres investigacions, demostrem que la supersimetria temporal pot convertir-se en una plataforma prometedora per a la fotònica integrada ja que ens permet dissenyar nous dispositius òptics versàtils i ultracompactes que poden jugar un paper clau en els processadors del futur.
Per tal de fer els resultats principals d'aquesta tesi doctoral el més generals possibles, es detalla com poder extrapolar-los a altres camps de la física com ara la acústica i la mecànica quàntica. / [EN] To date, communication networks based on optical fibers are rapidly approaching their capacity limit as a direct consequence of the increment of the data traffic demand in the last decade due to the ubiquity of smartphones, tablets, social networks, cloud computing applications, streaming services including video and gaming, and machine-to-machine communications. In such a scenario, a new class of optical fiber which is able to integrate the capacity of several classical optical fibers approximately in the same transverse section as that of the original one, the multi-core fiber (MCF), has been recently proposed to overcome the capacity limits of current optical networks.
However, the possibility of exploiting the full potential of an MCF requires to deeply understand the electromagnetic phenomena that can be observed when guiding light in this optical medium. In this vein, in the first part of this thesis, we analyze theoretically these phenomena and, next, we study the suitability of the MCF technology in optical transport networks using radio-over-fiber transmissions. These findings could be of great utility for 5G and Beyond-5G cellular technology in the next decades.
In addition, the close connection between the mathematical framework of quantum mechanics and electromagnetism becomes a great opportunity to explore ground-breaking design strategies of these new fibers that allow us to expand their basic functionalities. Revolving around this idea, in the second part of this thesis we propose to design a new class of MCFs using the mathematics of supersymmetry (SUSY), emerged within the context of string and quantum field theory as a means to unify the basic interactions of nature (strong, electroweak, and gravitational interactions). Interestingly, a supersymmetric MCF will allow us, not only to propagate the light, but also to process the information of users during propagation.
Finally, we conclude this thesis by introducing a paradigm shift that allows us to design disruptive optical devices. We demonstrate that the basic ideas of SUSY in non-relativistic quantum mechanics, restricted to the space domain to clarify unsolved questions about SUSY in string and quantum field theory, can also be extended to the time domain, at least within the framework of photonics. In this way, it is shown that temporal supersymmetry may serve as a key tool to judiciously design versatile and ultra-compact optical devices enabling a promising new platform for integrated photonics.
For the sake of completeness, we indicate how to extrapolate the main results of this thesis to other fields of physics, such as acoustics and quantum mechanics. / Macho Ortiz, A. (2019). Multi-Core Fiber and Optical Supersymmetry: Theory and Applications [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/124964
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Development of Ruddlesden-Popper type intercalation cathode material for all solid-state fluoride ion batteries / フッ化物イオン全固体電池に向けたRuddlesden-Popper型インターカレーション正極材料の開発Miki, Hidenori 25 March 2024 (has links)
京都大学 / 新制・課程博士 / 博士(人間・環境学) / 甲第25387号 / 人博第1129号 / 新制||人||262(附属図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 内本 喜晴, 教授 田部 勢津久, 教授 吉田 鉄平, 教授 雨澤 浩史 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM
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