DC-DC Converter Control System for the Energy Harvesting from Exercise Machines System

Current exercise machines create resistance to motion and dissipate energy as heat. Some companies create ways to harness this energy, but not cost-effectively. The Energy Harvesting from Exercise Machines (EHFEM) project reduces the cost of harnessing the renewable energy. The system architecture includes the elliptical exercise machines outputting power to DC-DC converters, which then connects to the microinverters. All microinverter outputs tie together and then connect to the grid. The control system, placed around the DC-DC converters, quickly detects changes in current, and limits the current to prevent the DC-DC converters and microinverters from entering failure states. An artificial neural network learns to mitigate incohesive microinverter and DC-DC converter actions. The DC-DC converter outputs 36 V DC operating within its specifications, but the microinverter drops input resistance looking for the sharp decrease in power that a solar panel exhibits. Since the DC-DC converter behaves according to Ohm’s Law, the inverter sees no decrease in power until the voltage drops below the microinverter’s minimum input voltage. Once the microinverter turns off, the converter regulates as intended and turns the microinverter back on only to repeat this detrimental cycle. Training the neural network with the back propagation algorithm outputs a value corresponding to the feedback voltage, which increases or decreases the voltage applied from the resistive feedback in the DC-DC converter. In order for the system to react well to changes on the order of tens of microseconds, it must read ADC values and compute the output neuron value quicker than previous control attempts. Measured voltages and currents entering and leaving the DC-DC converter constitute the neural network’s input neurons. Current and voltage sensing circuit designs include low-pass filtering to reduce software noise filtering in the interest of speed. The complete solution slightly reduces the efficiency of the system under a constant load due to additional component power dissipation, while actually increasing it under the expected varying loads

Literary criticism as feminist argument in Mary Wollstonecraft's A Vindication of the Rights of Woman

Mary Wollstonecraft's A Vindication ofthe Rights of Woman makes its feminist argument primarily through literary criticism. Recent scholarship has generally considered the literary critical dimension of Rights of Woman as a minor component of Wollstonecraft's explicit political argument and cultural critique. This thesis locates and analyzes three literary critiques in Rights of Woman in order to illustrate the specificity of Wollstonecraft's methods. Wollstonecraft's critique of Milton utilises a practice of quotation and commentary, and interrogates his prominent role in literary and political canons. Her critique of Rousseau's Emile is highly instructive because she both attacks its content and attempts to undercut the modes by which this paradigmatic statement of the submissive domestic female had become 'a prevailing opinion of a sexual character'. Wollstonecraft's critique of John Gregory, the author of the influential conduct book A Legacy to His Daughters, claims that this work perpetuates Rousseau's repressive norms, even without the conscious knowledge of its apparently capable author. In doing so, Wollstonecraft theorizes the existence of a self-reproducing 'male' literary tradition, one which comprises a broad range of texts, whether by 'great' writers or less gifted men, a notion which challenges benevolent images of a purist canon of aesthetic value. In the development of her criticism, Wollstonecraft draws from two contemporary critical traditions. The first is that of the bluestocking women, whose public mastery of literary knowledge gives them the status to promulgate social agendas. The second is the literary periodical, which stands at the very centre of print culture in the eighteenth century. A specific analysis of the literary critical dimension of Rights of Woman illuminates new aspects of the organization and rhetoric of this key work

Flow Model of Offshore Input of Nitrogen into the Narragansett Bay

Nitrogen is an important nutrient in ecosystems, as it is used in many biological processes, including the creation of DNA and RNA. However, excess nitrogen in an ecosystem can have adverse effects, such as triggering algal blooms, which limit sunlight penetration to bottom growth, and create anoxic zones. Large scale strategies to remove excess nitrogen from wastewater treatment plants have been utilized, but they are expensive and can potentially remove too much, while increasing greenhouse gas emissions. Thus, it is essential that we understand the accurate full nitrogen budget for an estuary. Narragansett Bay, an important coastal marine ecosystem that supports both natural life and human industry, has been the subject of many studies of nutrient conditions. Sources of nitrogen input from the atmosphere and the land have been studied rather intently. However, input of nitrogen from offshore – specifically, what happens to the nitrogen from the mouth of the Bay on its way to the productive mid-portion – is not well understood. While some past studies have mentioned this source, they do not go into depth, and none use direct measurements to inform their estimation of offshore nitrogen influx as being about 15% of total nitrogen input. Recent data on flow and nutrient concentrations suggest that the nitrogen flux through the mouth of the Bay is now in excess of what comes in from treatment plants; this may also be supported by research in other estuaries, such as Chesapeake Bay. This project aims to take a deeper look at the flow of nitrogen into Narragansett Bay from offshore sources. To obtain direct nitrogen measurements, 3 samples were taken at different depths, from each of 3 Acoustic Doppler Current Profiler (ADCP) locations, for a total of 9 samples, at the mouth of the East Passage. These samples were then sent to a lab for analysis of concentrations of the main constituents of marine nitrogen content, NO2, NO3, and NH4+. After the nitrogen data were received, they and ADCP current velocities were fitted into a circulation and transport model for the East Passage, using the MATLAB computational platform. The numerical simulations will predict how nitrogen concentrations entering in the bottom water at the mouth of the Bay evolve during transit north to the mid- Bay

Invariant NKT cells and rheumatic disease: Focus on primary sjogren syndrome

Primary Sjogren syndrome (pSS) is a complex autoimmune disease mainly affecting salivary and lacrimal glands. Several factors contribute to pSS pathogenesis; in particular, innate immunity seems to play a key role in disease etiology. Invariant natural killer (NK) T cells (iNKT) are a T-cell subset able to recognize glycolipid antigens. Their function remains unclear, but studies have pointed out their ability to modulate the immune system through the promotion of specific cytokine milieu. In this review, we discussed the possible role of iNKT in pSS development, as well as their implications as future markers of disease activity

Vinculando avaliações TIMSS e NAEP para avaliar tendências internacionais em realizações

The Trends in International Mathematics and Science Study (TIMSS) makes it possible to compare the performance of students in the US in Mathematics and Science to the performance of students in other countries. TIMSS uses four international benchmarks for describing student achievement: Low, Intermediate, High, and Advanced. In this study, we linked the eighth-grade Math TIMSS and NAEP scales using equipercentile equating to (a) help better interpret U.S. eighth-grade students’ performance on TIMSS, and (b) investigate the progress of eighth-grade U.S. students over time relative to the progress of students in other countries. Results indicated that relative to other countries, U.S. eighth-grade students increased with respect to the “At or Above Basic” NAEP Achievement level, but that other countries saw larger improvements in the higher achievement level categories, relative to the US. This finding may reflect the emphasis of No Child Left Behind on raising lower achievement to “proficient.” However, with respect to “Advanced” mathematics achievement, eighth-grade U.S. students showed less improvement than students in other countries. Las Tendencias en Matemáticas Internacionales y Estudios Ciencias (TIMSS) le permite comparar el rendimiento de los estudiantes en los EE.UU. en Matemáticas y Ciencia con el rendimiento de otros estudiantes de los países. El TIMSS utiliza cuatro puntos de referencia internacionales para describir el rendimiento del estudiante: bajo, intermedio y avanzado de alta. En este estudio, asociamos las escalas de TIMSS matemáticas y NAEP dadas en octavo grado utilizando equipercentile equivalente a (a) ayuda a interpretar mejor el rendimiento de octavo grado en el TIMSS, y (b) para investigar el progreso de los estudiantes de 8º grado en los Estados Unidos en el tiempo sobre el progreso de los estudiantes de otros países. Los resultados indicaron que, en comparación con otros países, los estudiantes de 8º grado de Estados Unidos aumentaron desde el nivel “igual o superior al básico” NAEP logro, pero otros países marcaron la mayor mejora en la mayoría de las categorías de nivel de rendimiento en los EE.UU.. Este hallazgo puede reflejar el énfasis de No Child Left Behind (NCLB) para elevar el rendimiento más bajo de "competente". Sin embargo, en cuanto a rendimiento en matemáticas “avanzada”, los estudiantes estadounidenses de octavo grado mostraron menor mejoría de los estudiantes de otros países.As Tendências em Matemática Internacional e Estudos em Ciências (TIMSS) permite comparar o desempenho dos estudantes nos EUA em Matemática e Ciência com o desempenho de alunos de outros países. O TIMSS usa quatro referências internacionais para descrever o desempenho dos alunos: Baixo, Intermediário, Alto e Avançado. Neste estudo, associamos as escalas de TIMSS e NAEP de matemática dada na 8ª série usando equivalentes equipercentile para (a) ajudar a interpretar melhor o desempenho dos estudantes da oitava série no TIMSS, e (b) investigar o progresso de estudantes de 8ª série nos EUA ao longo do tempo relativo ao progresso dos alunos em outros países. Os resultados indicaram que, em relação a outros países, os estudantes de 8º ano dos Estados Unidos aumentaram em relação ao nível “no ou acima do básico” de realização NAEP, mas que outros países marcaram melhorias maiores nas categorias de maior nível de desempenho em relação aos EUA. Essa descoberta pode refletir na ênfase de Nenhuma Criança Deixada Para Trás (No Child Left Behind) em elevar a realização inferior para "proficiente". No entanto, no que diz respeito à conquista de matemática “Avançada,” os estudantes americanos de 8ª série apresentaram menor melhora do que os estudantes de outros países

A promising new ELISA diagnostic test for cattle babesiosis based on Babesia bigemina Apical Membrane Antigen-1.

Babesiosis due to Babesia bigemina is a relevant tick‑borne disease, affecting cattle worldwide. Many surface proteins of the pathogen including the Apical Membrane Antigen 1 (AMA‑1) ‑ have been analysed for vaccine and diagnostic purposes. This study focused on B. bigemina AMA‑1 and on its use for the assessment of diagnostic tests. After bioinformatic analyses, AMA‑1 codifying region was amplified and cloned into an expression vector used to induce protein synthesis in Escherichia coli cells. AMA‑1 was purified by affinity chromatography and used to set up the best condition for an ELISA protocol. Bovine field sera positive to B. bigemina were used to evaluate the presence of anti‑AMA‑1 antibodies. In order to verify the assay specificity, sera positive to Babesia bovis or to the piroplasm Theileria annulata were also included. Significant differences were obtained between sera negative to both B. bigemina and B. bovis and samples positive to B. bigemina, to B. bovis or to both pathogens. No significant reaction was observed with T. annulata positive sera. The results showed that AMA‑1 protein is suitable to be used as antigen in diagnostic assays for babesiosis diagnosis in cattle, as it does not show any cross reaction with anti-T. annulata antibodies

Evaluaciones de validez: introducción a la sección especial

Background: Validation is the process of providing evidence that tests and questionnaires are adequately and appropriately fulfi lling the purposes for which they are developed. In this special issue, experts from several countries describe specifi c approaches to test validation and provide examples of their approach. These approaches and examples illustrate the validation framework implied by the Standards for Educational and Psychological Testing. Method: We describe the Standards’ approach for building a validity argument based on validity evidence based on test content, response processes, internal structure, relations to other variables, and testing consequences. Results: The fi ve articles provide comprehensive examples of gathering data regarding these fi ve sources of evidence and how they contribute to the validation of the use of test scores for particular purposes. Conclusions: These fi ve articles provide concrete examples of how the fi ve sources of validity evidence suggested by the Standards can be used to develop a sound validity argument to support the use of a test for its intended purposes.Antecedentes: la validación es el proceso de aportar evidencias de que las evaluaciones mediante tests y cuestionarios cumplen adecuada y apropiadamente los objetivos para los que se elaboran. En este número especial expertos de varios países describen enfoques específi cos para la validación y aportan ejemplos. Estos enfoques y ejemplos ilustran el marco de validación implicado por los Standards for Educational and Psychological Testing. Método: describimos la aproximación de los Standards para elaborar un argumento de validez a partir de evidencias de validez basadas en el contenido del test, los procesos de respuesta, la estructura interna, las relaciones con otras variables y las consecuencias del uso del test. Resultados: los cinco artículos aportan ejemplos comprehensivos de obtención de datos en relación con las cinco fuentes de evidencia, y de cómo contribuyen a la validación del uso de las puntuaciones en el test para objetivos específi cos. Conclusiones: los cinco artículos aportan ejemplos concretos de cómo las cinco fuentes de evidencias de validez sugeridas por los Standards pueden utilizarse para elaborar un sólido argumento de validez que apoye el uso de test para sus objetivos previstos