Design and implementation of control system for magnetic suspension device

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 57).The purpose of this thesis was to gain more knowledge and experience in the areas of modeling, dynamics, and applied control theory. A single-axis magnetic suspension device originally designed by Professor David Trumper for classroom demonstrations was chosen to improve the understanding of the previously mentioned topics. The dynamics of these types of systems provide interesting control challenges due to the nonlinear nature of its dynamics. As a result, designing of a control system for this device required the understanding and experimentation of two nonlinear controls techniques: linearization of the plant around an operating point, and feedback linearization. A combination of electromagnetic theory and experimentation was used to model the suspension actuator, and two different controllers were designed and implemented using the different controls methods.by Omar Carrasquillo.S.B

Cervantes y el Quijote [Texto impreso]El hombre, el libro y la época

Justo de Lara es seudónimo de José Armas y Cárdenas

El Quijote y su época

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2012-201

Design of inflatable solar concentrator

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (pages 115-116).Solar concentrators improve the performance of solar collection systems by increasing the amount of usable energy available for a given collector size. Unfortunately, they are not known for their light weight and portability, which is ideal for basic applications like solar cooking. The goal of the project was to a design a light-weight and portable solar concentrator with minimal tracking requirements. The concept of an inflatable compound parabolic concentrator was developed, which required modifying the theoretical profile geometry. An analytical model was created to predict the efficiency of the system for different design parameter configurations. The model was used to develop a design and manufacturing process which was used to design and manufacture small-scale and full-scale prototypes. Experiments were designed to test the performance of the concentrators and the test results were used to determine a model accuracy of 11.4 1.3 % and 1.9±1.6% using the small-scale prototype and full-scale prototype, respectively.by Omar Carrasquillo.S.M

Update on Dihydropteroate Synthase (DHPS) Mutations in Pneumocystis jirovecii

A Pneumocystis jirovecii is one of the most important microorganisms that cause pneumonia in immunosupressed individuals. The guideline for treatment and prophylaxis of Pneumocystis pneumonia (PcP) is the use of a combination of sulfa drug-containing trimethroprim and sulfamethoxazole. In the absence of a reliable method to culture Pneumocystis, molecular techniques have been developed to detect mutations in the dihydropteroate synthase gene, the target of sulfa drugs, where mutations are related to sulfa resistance in other microorganisms. The presence of dihydropteroate synthase (DHPS) mutations has been described at codon 55 and 57 and found almost around the world. In the current work, we analyzed the most common methods to identify these mutations, their geographical distribution around the world, and their clinical implications. In addition, we describe new emerging DHPS mutations. Other aspects, such as the possibility of transmitting Pneumocystis mutated organisms between susceptible patients is also described, as well as a brief summary of approaches to study these mutations in a heterologous expression system

Importance of tissue sampling, laboratory methods, and patient characteristics for detection of Pneumocystis in autopsied lungs of non-immunosuppressed individuals

To understand the epidemiological significance of Pneumocystis detection in a lung tissue sample of non-immunosuppressed individuals, we examined sampling procedures, laboratory methodology, and patient characteristics of autopsy series reported in the literature. Number of tissue specimens, DNA-extraction procedures, age and underlying diagnosis highly influence yield and are critical to understand yield differences of Pneumocystis among reports of pulmonary colonization in immunocompetent individuals.publishersversionpublishe

Efficient transovarial transmission of Babesia Spp. in Rhipicephalus microplus ticks fed on water buffalo (Bubalus bubalis).

Water buffaloes can be infected by tick-borne pathogens (TBPs) in endemic areas where cattle and buffalo coexist. Among TBPs affecting buffaloes is the Apicomplexan hemoparasites Babesia bovis and B. bigemina, transmitted by Rhipicephalus microplus ticks. However, little empirical evidence exists on whether buffalo can support TBPs? infection and transmission. A cohort study was designed to measure the infestation levels of R. microplus in buffaloes as well as the ability of buffalo-fed ticks to transmit B. bovis and B. bigemina to their offspring. Tick infestation of different life stages was quantified in cattle and buffalo kept in field conditions in western Cuba. Engorged adult female ticks were allowed to lay eggs in controlled conditions of humidity and temperature, and reproductive parameters were measured and analyzed. Hosts and tick larvae were tested for the presence of Babesia spp. using species-specific qPCR assays. Tick infestation was not observed in adult buffaloes. However, buffalo and cattle calves were equally infested, although the larval survival rate was higher in cattle calves than in buffalo calves. All larval pools (31) obtained from the adult female ticks were positive for B. bovis, whereas only 68% (21/31) was positive for B. bigemina. Among the 10 larval pools negative for B. bigemina, three proceeded from adult females fed on Babesia-negative buffaloes. The other seven pools were from Babesia-positive animals, three from cattle and four from buffalo calves. Babesia infection levels in tick larvae, quantified by qPCR, were similar in female ticks fed on buffalo and bovine calves. We conclude that water buffalo can sustain tick vector populations and support Babesia infection in levels high enough as to be infective for ticks. Our results also validated the hypothesis that adult female ticks fed on buffalo can transmit the pathogens B. bovis and B. bigemina to their offspring. Nevertheless, further laboratory studies are needed to address the question of whether the transovarial transmission of Babesia occurs in the following settings: (1) When adult females are infected previous to the feeding on the buffalo or/and (2) when the adult females acquire the infection while feeding on the buffalo

El Alcázar de Madrid. Del Castillo Trastámara al Palacio de los Austrias (Ss. XV-1543)

Resumen: El alcázar medieval de Madrid se convirtió en la gran residencia de los Austrias desde la llegada de Carlos I al reinado de Carlos II. En la Nochebuena de 1734, reinando ya Felipe V de Borbón, el palacio sufrió un devastador incendio, resultado del cual se inicia la construcción del nuevo Palacio Real, ya barroco, sobre su solar. En esta investigación nos ocupamos de reconstruir la historia –hasta ahora fragmentada– de ese castillo medieval, aportando nuevos datos documentales acerca de las sucesivas intervenciones sufridas en el edificio. Nos centramos de forma especial en las obras realizadas en el período de los Reyes Católicos y en las primeras encargadas por Carlos V, antes de la definitiva real cédula de 1536 que marca el comienzo de un nuevo capítulo en la historia constructiva del edificio al transformarse de manera definitiva el viejo castillo en un palacio residencial, pero subrayando al tiempo el valor simbólico de la “Cuadra Rica” y las salas de aparato de la época TrastámaraAbstract: The medieval Alcázar (fortress) of Madrid was transformed into the residential palace of the Austriandynasty in Spain from the reign of Charles I through that of Charles II. On Christmas Eve 1734, duringthe reign of the Bourbon king Philip V, the palace suffered a devastating fire, resulting in the constructionof a new Royal palace, already baroque, on the same site. This research reconstructs the history – untilnow fragmented – of this lost medieval castle, contributing new source materials concerning the successiveinterventions carried out on the building. Specifically, this investigation focuses on the improvementsrealized during the period of the Catholic Monarchs and the first works commissioned by Charles V, priorto the definitive royal bond of 1536. This document marks the beginning of a new chapter in the constructivehistory of the building, when the old castle was transformed definitively into a residential palace,while highlighting the symbolic value of the Sala Rica and the rooms of protocol constructed during theTrastámara period