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SCHEDULING AND RESOURCE ALLOCATION IN WIRELESS SENSOR NETWORKS
Year of Dissertation:
In computer science and telecommunications, wireless sensor networks are an active research area. Each sensor in a wireless sensor network has some pre-defined or on demand tasks such as collecting or disseminating data. Network resources, such as broadcast channels, number of sensors, power, battery life, etc., are limited. Hence, a schedule is required to optimally allocate network resources so as to maximize some profit or minimize some cost. This thesis focuses on scheduling problems in the wireless sensor networks environment. In particular, we study three scheduling problems in the wireless sensor networks: broadcast scheduling, sensor scheduling for area monitoring, and content distribution scheduling. For each problem the goal is to find efficient scheduling algorithms that have good approximation guarantees and perform well in practice.
De la península ibérica a Italia: concepción y práctica teatral de las primeras comedias castellanas
Marta Albala Pelegrin
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Hispanic & Luso Brazilian Literatures & Languages
Ottavio Di Camillo
In my dissertation, De la península Ibérica a Italia: concepción y práctica teatral de las primeras comedias castellanas, I analyze the formation of early modern Spanish comedia, in the context of Italo-Iberian cultural exchanges. My aim is to incorporate the most popular Spanish plays of the first half of the sixteenth century into the larger scenario in which they belong: one that we could name the "formation of the genre of comedy". Works such as Juan del Encina's Eclogues, La Celestina (The Spanish Bawd), and Torres Naharro's Tinellaria and Soldadesca are seen in this light as milestones in a complex thread of contributions leading to the development in the seventeenth century of a Spanish Golden Age "national theater", and specifically in Lope de Vega comedia nueva, as well as to the Italian commedia erudita. Such a reconstruction has long been neglected due to the constitution of the Hispanic and the Italian literary studies, and the asymmetry between the Spanish and the Italian literary traditions, especially regarding the primacy of Italian "comedies" and "authors" in the constitution of a history of "western comedy". The formation of the genre of comedy it is seen in a new light within a textual and bibliographical history, grounded in the relationships among authors, printers, and readers. Cultural and merchant networks established between the Iberian and Italian Peninsulas helped to widespread not only books as commodities, but ideas and forms (genres) contained within them that would appeal to new audiences and readers. In my second chapter, I have reconstructed the possible ways in which these plays could have been represented, in contexts such as Alba de Tormes and Rome, by means of the analysis of internal text evidence (prompts, or configuration of the different scenes) and the extant records, both about its actual performances, and other contemporary spectacles. In order to make sense of the scarce available data, I have delved into architectural treatises (Vitruvio, Alberti, Peruzzi, Serlio), woodcuts, and extant Roman documents on contemporary theatrical performances. As a result of this reconstruction, Encina's latest plays, as well as Naharro's Soldadesca and Tinellaria, appear as deeply rooted in the avant-garde conception of the urban Roman scene, they share both techniques, and scene conceptions with avant-garde Italian authors. In my third chapter, I studied the function that comedies, such as Naharro's Tinellaria and Soldadesca, had at the time, insisting on the religious and political denunciations contained in them, as well as in their relationship with some discourses originating in the Lateran council. As a result of that, I have been able to delimit the circles, critical with the papacy of Julius II, in which these ideas originated, together with the political interests of those that voiced them.
A Critical and Cultural Poetics of the End: Self, Space, and Volatility in Los Angeles
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A Critical and Cultural Poetics of the End: Self, Space, and Volatility in Los Angeles delineates the correspondences between Los Angeles spaces--exterior, topographical, architectural, and imaginary--and aspects of the self--interiority, identity, experience, and desire--in fictional and non-fictional depictions of Los Angeles. Through close readings of key Los Angeles novels, essays, and films, this project emphasizes how the narrative "I" traverses urban space, focusing on the dissolution of boundaries between self and place. Los Angeles' sprawling, decentralized layout and rapidly-shifting landscape have a profound influence on narrative identity, generating a volatile and disquieting sense of self; this project also explores how the city's unique spatial orientation contributes to a literature and cinema of disillusionment exclusive to Los Angeles.
MAG does not Require NgR1, PirB or Sialic Acid Binding to Inhibit Neurite Outgrowth
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The Role of Gangliosides, NgR1, NgR2 and PirB Receptors in MAG Inhibition of Neurite Outgrowth by Najat Al-bashir Thesis Advisor: Dr. Marie T. Filbin Following injury, axons in the central nervous system (CNS) do not spontaneously regenerate, and this is due to several factors, one of which is the presence of myelin- associated inhibitors. There are three major myelin-associated inhibitors that have been identified, Nogo-66, myelin associated glycoprotein (MAG), and Oligodendrocyte myelin glycoprotein (OMgp). MAG is a member of immunoglobulin (IgG) super-family and contains 5 Ig-like domains in its extracellular domain. Like Nogo-66 and OMgp, MAG binds to a receptor complex consisting of NgR1- p75NTR-Lingo-1 to inhibit neurite outgrowth. MAG is also a sialic acid binding protein and specifically binds to gangliosides GT1b and GD1a. Recently, NgR2 was also shown to be a sialic acid- dependent binding receptor for MAG. Recently, paired immunoglobulin B (PirB) was also identified as a novel receptor for MAG, Nogo-66 and OMgp. Previously, we showed that the sialic acid binding activity of MAG is not necessary for its inhibitory effects. We mapped the sialic acid binding site on MAG to Arg 118 in the first Ig-domain. When this site is mutated, sialic acid binding is lost but MAG, when expressed by CHO cells, still retains its ability to inhibit neurite outgrowth. Also, we showed that a soluble form of MAG consisting of the MAG extracellular domain fused to the Fc portion of human IgG (MAG-Fc), and a truncated soluble form of MAG consisting iii only of the first three Ig-like domains (MAG (d1-3)-Fc), both bind to neurons in a sialic acid-dependent manner; however, only MAG-Fc inhibits neurite outgrowth. In addition, MAG mutated at Arg118 (MAG (R118A)-Fc), does not bind to neurons and could not inhibit neurite outgrowth. Recently, we mapped the inhibition site on MAG to Ig-domain 5, which is distinct from the sialic acid binding site. Others have reported that gangliosides are functional binding partners for MAG and are necessary for inhibition by MAG when expressed in immobilized membranes. They reported that neurons from mice deficient in the B1, 4-N-actylgalactosaminyltransferase (GalNAcT) gene, which lack all complex gangliosides including GT1b and GD1a, are not inhibited by MAG in immobilized membrane. Others have also shown that clustering gangliosides with antibodies in the absence of MAG is sufficient to inhibit neurite outgrowth via a mechanism engaging p75 NTR receptor. Here we show that clustering MAG (d1-3)-Fc can inhibit neurite outgrowth in neurons from wild type mice but not from GalNAcT deficient mice. We also show that MAG can inhibit neurite outgrowth independent of NgR1, PirB, and sialic acid binding. We show that neurons from GalNAcT deficient mice are inhibited by MAG as effectively as neurons from wild type mice. Also, we show that neurons from NgR1 deficient mice are inhibited by full length MAG and mutated MAG (MAG R118A) that cannot bind sialic acid residues. In addition, in the presence of PirB antibodies, both MAG- and mutated MAG (R118A)-expressing CHO were able to inhibit neurite outgrowth of neurons from NgR1 deficient mice and wild type mice. Taking all these results together, MAG interacts with another as yet unknown receptor(s), in addition to NgR's, PirB and sialic acid to inhibit neurite outgrowth.
Nanoacoustic Effects in Type-II Superconductors and Decoherence of Two-state Systems
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In this thesis we focus on two areas of research: nanoacoustic effects in superconductors, and decoherence of two-state systems due to radiation of acoustic phonons. In the first part of this thesis we propose two new nanoacoustic effects: induction of voltage by mechanical stress, and nucleation of a superconducting vortex by an acoustic standing wave. Both of these effects take place in type-II superconductors. In the second part we study relaxation processes via acoustic phonons of a particle in a double-well potential and of a flux qubit. Part 1: Mechanical stress causes motion of dislocations in solids. In a type-II superconductor a moving dislocation generates a pattern of current that exerts a force on the surrounding vortex lattice capable of depinning it. We show that the concentration and the speed of dislocations needed to produce depinning currents are within practical range. When external magnetic field and transport current are present, this effect generates voltage across the superconductor. In this manner, a type-II superconductor can serve as an electrical sensor of the mechanical stress. Nucleation of vortices in a superconductor below the first critical field can be assisted by transverse sound in the GHz frequency range. We work out from energy considerations that, in the presence of a sound wave, vortices enter and exit the superconductor at the frequency of the sound. The computed threshold parameters of the sound are shown to be within experimental reach. Part 2: We propose a method of computing phonon-induced relaxation of two-state systems that is based on symmetry arguments. This allows one to express the rates in terms of independently measurable parameters. For translationally and rotationally invariant systems the conservation of linear and angular momenta must be taken into account when formulating the interaction Hamiltonian. For a particle (e.g., electron or proton) in a rigid double-well potential embedded in a solid the rate is proportional to the seventh power of temperature. For a flux qubit the two-phonon relaxation is important only if the size of the qubit is much smaller than the phonon wavelength. Due to symmetry the two-phonon rate of both systems is proportional to the square of the bias. This allows for additional control of the relaxation rate.
Images of Chopin in the New World: Performances of Chopin's Music in New York City, 1839-1876
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This dissertation examines the reception history of the music of Fryderyk Chopin (1810-1849) in the city of New York from the first documented performance of his works, in 1839, until 1876, the year of the historic American tour of Hans von Bülow (1830-1894). The dynamics of those responses correspond with the growth of New York, which, during that time, experienced a dramatic transformation from a provincial city into a vibrant cultural metropolis. In addition, I aim to explore the evolution of musical aesthetics and taste within a larger scope that includes social, political, and cultural issues. That evolution is illustrated by the ways the music of Chopin was performed, disseminated, and criticized demonstrating the presence of points of intersection with other important artistic centers in Europe. My broader goal is to contribute to a better understanding of the dynamics of the musical life of the city in the thirty-seven years covered in this study. A meticulous work of documentation of hundreds of performances provides a valuable tool for scholars who wish to keep exploring that fascinating period in New York history, and the circumstances that paved the way for the future conditions of the musical life in the city and in the nation.
Jealousy Comprehension during Middle Childhood: The Roles of Perspective Taking, Gender, and Maternal Reminiscing within Narrative Construction
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The aim of the current study was to provide an extensive assessment of the socio-cognitive development of children's jealousy understanding during middle childhood within the context of narrative construction. In doing so, influences of perspective-taking ability, gender, and maternal reminiscing on children's ability to understand -and talk about- jealousy (a complex emotion) between the ages of 5 and 11 were examined. In total, 40 girls (M age = 8y;2m, SD = 2y;1m), 40 boys (M age = 8y;7m, SD = 2y;0m), and their mothers participated. Children completed a series of narrative tasks that were coded for emotion understanding: a fictional narrative about a frog experiencing jealousy, post-story probe questions, an individual autobiographical narrative about their own experience of jealousy, and a co-constructed personal narrative in which children and their mothers were asked to talk about a time their child experienced jealousy. Additionally, mothers completed the fictional narrative task for an adult comparison to children's abilities. Children were also administered measures of socio-cognitive development (Test of Emotion Comprehension, Test of Perspective-Taking Ability) and intellectual development (Verbal Intelligence - PPVT, Nonverbal Intelligence - TONI), and mothers were administered a measure of Verbal Intelligence (PPVT). Overall, findings from the current study provide evidence that (1) children exhibit an increased understanding of jealousy across multiple measures of emotion understanding between the ages of 5 and 11, (2) there is considerable overlap in the feelings of jealousy and envy during middle childhood, (3) perspective taking is linked to children's abilities to talk about another's feelings during middle childhood, and (4) girls' emotion understanding is displayed and acquired in a more interpersonal context than boys'. Furthermore, the present study extends the literature on maternal-guided reminiscing to include assessment during middle childhood, examining the roles of both style and content, and through evaluating both parties' discourse. In doing so, maternal elaboration was found to be beneficial for children's autobiographical narrative abilities during middle childhood. Results are discussed in relation to socialization practices behind children's expression of jealousy -a negative emotion associated with interpersonal rivalry- that is frequently experienced, but that American culture says should not be expressed.
"I'm not trying to go back": Young women's strengths navigating their return from incarceration
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This is a qualitative, grounded-theory study of thirteen young women between the ages of 18 and 26 who were returning back to their lives in New York City after prison or an extended jail incarceration. The women spent anywhere from 8 months to 8 years incarcerated and were home between three months and three years from the time of their release. The study includes findings based on analysis and interpretations of the interviews, implications for future research and practice that center around the women's use of time while incarcerated, their connectedness to family, friends and staff, both while in prison and upon release, and the impact of both of those on their ability to stay free. The study includes implications for social work and correctional research and practice, and is grounded in women's relational theory and developmental frameworks.
Quantum dislocations in solid Helium-4
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In this thesis the following problems on properties of solid 4He are considered: i) the role of long-range interactions in suppression of dislocation roughening at T = 0; ii) the combined effect of 3He impurities and Peierls potential on shear modulus softening; iii) the dislocation superclimb and its connection to the phenomenon of “giant isochoric compressibility” ; iv) non-linear dislocation response to the applied stress and stress-induces dislocation roughening as a I-order phase transition in 1D at finite temperature. First we investigate the effect of long-range interactions on the state of edge dislocation at T = 0. Such interactions are induced by elastic forces of the solid. We found that quantum roughening transition of a dislocation at T = 0 is completely suppressed by arbitrarily small long-range interactions between kinks. A heuristic argument is presented and the result has been verified by numerical Monte-Carlo simulations using Worm Algorithm in J-current model. It was shown that the Peierls potential plays a crucial role in explaining the elastic properties of dislocations, namely shear modulus softening phenomenon. The crossover from T = 0 to finite temperatures leads to intrinsic softening of the shear modulus and is solely controlled by kink typical energy. It was demonstrated that the mechanism, involving only the binding of 3He impurities to the dislocations, requires an unrealistically high concentrations of defects (or impurities) in order to explain the shear modulus phenomenon and therefore an inclusion of Peierls potential in consideration is required. Superclimbing dislocations, that is the edge dislocations with the superfluidity along the core, were investigated. The theoretical prediction that superclimb is responsible for the phenomenon of “giant isochoric compressibility ” was confirmed by Monte-Carlo simulations. It was demonstrated that the isochoric compressibility is suppressed at low temperatures. The dependence of compressibility on the dislocation length was shown to be strongly dependent on long-range interaction. Non-linear behavior at high stresses was considered. The dislocation was observed to exhibit two types of behavior depending on the dislocation size: reversible and hysteretic. In the reversible regime responses of superclimbing dislocations exhibit sharp resonant peaks. We attribute this feature to the resonant creation of jog-antijog pairs. The peak in the compressibility results in the dip in the speed of sound which we believe was observed in “ UMASS-sandwich” mass-transport experiments. The hysteresis revealed an unusually strong sensitivity to the dislocation size signifying that the stress-induced roughening is a I-order phase transition in 1D at finite T.
Neural Effects of Exposure to the Environmental Chemical, Bisphenol A, During Development
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Exposure to Bisphenol A (BPA), an environmental chemical, has been linked to changes in physiology, neural development, and behavior. The focus of this study was to determine the effects of BPA exposure, during a short developmental window, on physiology, activity, anxiety, cognition, and neurochemistry. In prenatal study, dams were administered 100 mcg/kg/day orally, from gestational day 16 to parturition. Postnatal study pups received subcutaneous injection of 60 or 100 mcg/kg BPA from postnatal day 0 to 6. All pups were weighed, examined for evidence of vaginal opening, and, at adulthood, performed behavioral tasks measuring locomotor activity, anxiety, and visual and spatial memory. Brain monoamines were measured using high performance liquid chromatography in the postnatal group. Prenatal BPA contributed to low juvenile body weight in both sexes and adult overweight in male subjects. Hyperactivity and memory deficits were observed in both sexes of BPA treated subjects. Postnatal 100 mcg/kg BPA females experienced delayed vaginal opening, less anxiety behavior in elevated plus maze, and spatial memory impairments. BPA treated subjects of both sexes had increased norepinephrine and dopamine turnover in basolateral amygdala and hippocampus, areas which are implicated in anxiety and cognition, respectively. The data suggests that BPA exposure during perinatal life causes disruptions in physiology, behavior, memory and neurochemistry that persist to adulthood. In addition, postnatal effects of BPA may be mediated by alterations in central monoaminergic function.