1,585 research outputs found

    Bipolar current driver for memory circuits

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    Circuit which logically determines the state of a flip-flop and amplifies the current from a clock pulse provides a bipolar driving current to a memory circuit, the polarity of which is determined by the state of a flip-flop. This principle may be applied to various memory driving circuits where power dissipation must be minimized

    Flipflop interrogator and bi-polar current driver Patent

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    Interrogator and current driver circuit for combination with transistor flip-flop circui

    Optimized Compilation of Aggregated Instructions for Realistic Quantum Computers

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    Recent developments in engineering and algorithms have made real-world applications in quantum computing possible in the near future. Existing quantum programming languages and compilers use a quantum assembly language composed of 1- and 2-qubit (quantum bit) gates. Quantum compiler frameworks translate this quantum assembly to electric signals (called control pulses) that implement the specified computation on specific physical devices. However, there is a mismatch between the operations defined by the 1- and 2-qubit logical ISA and their underlying physical implementation, so the current practice of directly translating logical instructions into control pulses results in inefficient, high-latency programs. To address this inefficiency, we propose a universal quantum compilation methodology that aggregates multiple logical operations into larger units that manipulate up to 10 qubits at a time. Our methodology then optimizes these aggregates by (1) finding commutative intermediate operations that result in more efficient schedules and (2) creating custom control pulses optimized for the aggregate (instead of individual 1- and 2-qubit operations). Compared to the standard gate-based compilation, the proposed approach realizes a deeper vertical integration of high-level quantum software and low-level, physical quantum hardware. We evaluate our approach on important near-term quantum applications on simulations of superconducting quantum architectures. Our proposed approach provides a mean speedup of 5×5\times, with a maximum of 10×10\times. Because latency directly affects the feasibility of quantum computation, our results not only improve performance but also have the potential to enable quantum computation sooner than otherwise possible.Comment: 13 pages, to apper in ASPLO

    Comparative in silico analysis identifies bona fide MyoD binding sites within the Myocyte Stress 1 gene promoter

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    <p>Abstract</p> <p>Background</p> <p>Myocyte stress 1 (MS1) is a striated muscle actin binding protein required for the muscle specific activity of the evolutionary ancient myocardin related transcription factor (MRTF)/serum response factor (SRF) transcriptional pathway. To date, little is known about the molecular mechanisms that govern skeletal muscle specific expression of MS1. Such mechanisms are likely to play a major role in modulating SRF activity and therefore muscle determination, differentiation and regeneration. In this study we employed a comparative <it>in silico </it>analysis coupled with an experimental promoter characterisation to delineate these mechanisms.</p> <p>Results</p> <p>Analysis of MS1 expression in differentiating C2C12 muscle cells demonstrated a temporal differentiation dependent up-regulation in <it>ms1 </it>mRNA. An <it>in silico </it>comparative sequence analysis identified two conserved putative myogenic regulatory domains within the proximal 1.5 kbp of 5' upstream sequence. Co-transfecting C2C12 myoblasts with <it>ms1 </it>promoter/luciferase reporters and myogenic regulatory factor (MRF) over-expression plasmids revealed specific sensitivity of the <it>ms1 </it>promoter to MyoD. Subsequent mutagenesis and EMSA analysis demonstrated specific targeting of MyoD at two distinct E-Boxes (E1 and E2) within identified evolutionary conserved regions (ECRs, α and β). Chromatin immunoprecipitation (ChIP) analysis indicates that co-ordinated binding of MyoD at E-Boxes located within ECRs α and β correlates with the temporal induction in <it>ms1 </it>mRNA.</p> <p>Conclusion</p> <p>These findings suggest that the tissue specific and differentiation dependent up-regulation in <it>ms1 </it>mRNA is mediated by temporal binding of MyoD at distinct evolutionary conserved E-Boxes within the <it>ms1 </it>5' upstream sequence. We believe, through its activation of <it>ms1</it>, this is the first study to demonstrate a direct link between MyoD activity and SRF transcriptional signalling, with clear implications for the understanding of muscle determination, differentiation and regeneration.</p

    Random Forest-Integrated Analysis in AD and LATE Brain Transcriptome-Wide Data to Identify Disease-Specific Gene Expression

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    Alzheimer\u27s disease (AD) is a complex neurodegenerative disorder that affects thinking, memory, and behavior. Limbic-predominant age-related TDP-43 encephalopathy (LATE) is a recently identified common neurodegenerative disease that mimics the clinical symptoms of AD. The development of drugs to prevent or treat these neurodegenerative diseases has been slow, partly because the genes associated with these diseases are incompletely understood. A notable hindrance from data analysis perspective is that, usually, the clinical samples for patients and controls are highly imbalanced, thus rendering it challenging to apply most existing machine learning algorithms to directly analyze such datasets. Meeting this data analysis challenge is critical, as more specific disease-associated gene identification may enable new insights into underlying disease-driving mechanisms and help find biomarkers and, in turn, improve prospects for effective treatment strategies. In order to detect disease-associated genes based on imbalanced transcriptome-wide data, we proposed an integrated multiple random forests (IMRF) algorithm. IMRF is effective in differentiating putative genes associated with subjects having LATE and/or AD from controls based on transcriptome-wide data, thereby enabling effective discrimination between these samples. Various forms of validations, such as cross-domain verification of our method over other datasets, improved and competitive classification performance by using identified genes, effectiveness of testing data with a classifier that is completely independent from decision trees and random forests, and relationships with prior AD and LATE studies on the genes linked to neurodegeneration, all testify to the effectiveness of IMRF in identifying genes with altered expression in LATE and/or AD. We conclude that IMRF, as an effective feature selection algorithm for imbalanced data, is promising to facilitate the development of new gene biomarkers as well as targets for effective strategies of disease prevention and treatment

    Prevalence of recurrent wheezing in infants

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    OBJECTIVE: To identify the prevalence of recurrent wheezing in infants in the city of Curitiba, PR, Brazil. METHODS: A cross-sectional study carried out by means of administering questionnaires to the parents of infants aged 12 to 15 months attending health centers for immunization during the period between August 2005 and December 2006. This is a standardized and validated instrument consisting of questions on demographic characteristics, wheezing, respiratory infections and risk factors. At the time of the study the City Health Department had 107 health centers, 35 of which were selected by lots and distributed homogeneously across the municipal territory. RESULTS: A total of 1,364 infants (45.4%) had episodes of wheezing during their first 12 months of life, with onset at 5.5±3.1 months (mean ± standard deviation), and 678 (22.6%) had had three or more episodes. In 84.6% of the wheezing children treatment was with β2-agonists, with inhaled corticosteroids in 18.5%, oral corticosteroids in 24.3% and leukotriene receptor antagonists were used with 5.4%. The wheezing children exhibited nocturnal symptoms, intense difficulty breathing and visits to emergency services in the proportions of 58.9, 46.2 and 57.6%, respectively; 12.7% were admitted to hospital for asthma and 10.9% had had a medical diagnosis of asthma. Nocturnal symptoms, visits to emergency, severity of symptoms, hospital admissions for asthma and medical diagnoses of asthma were all more common among those who had suffered three or more crises (p < 0.001). CONCLUSIONS: There is an elevated prevalence of wheezing among the infants of Curitiba, with early onset and elevated morbidity. It is possible that these infants represent a large contingent of asthmatics.OBJETIVO: Verificar a prevalência da sibilância recorrente em lactentes na cidade de Curitiba (PR). MÉTODOS: Estudo transversal pela aplicação de questionários aos pais de lactentes, idade entre 12 e 15 meses, que procuraram unidades de saúde para imunização no período entre agosto de 2005 e dezembro de 2006. Este instrumento padronizado e validado consiste de perguntas sobre características demográficas, sibilância, infecções respiratórias e fatores de risco. Durante o período de estudo, a Secretaria Municipal de Saúde possuía 107 unidades de saúde, das quais 35 foram selecionadas por sorteio e distribuídas homogeneamente no território municipal. RESULTADOS: Um total de 1.364 lactentes (45,4%) apresentou um ou mais episódios de sibilância nos primeiros 12 meses de vida, com início aos 5,5±3,1 meses (média ± desvio padrão), e 678 (22,6%) tiveram três ou mais episódios. Utilizaram β2-agonistas, corticóides inalatórios, corticóides orais e antagonistas do receptor de leucotrienos 84,6, 18,5, 24,3 e 5,4% dos sibilantes, respectivamente. Sintomas noturnos, dificuldade intensa para respirar e visitas a emergência estiveram presente em 58,9, 46,2 e 57,6% dos lactentes que sibilaram; destes, 12,7% foram hospitalizados por asma e 10,9% tiveram diagnóstico médico de asma. Sintomas noturnos, visitas à emergência, gravidade dos sintomas, hospitalização por asma e diagnóstico médico de asma foram mais freqüentes entre os que apresentaram três ou mais crises (p < 0,001). CONCLUSÃO: A prevalência de lactentes sibilantes em Curitiba é elevada, com início precoce e alta morbidade. Possivelmente, esses lactentes representam um contingente expressivo de asmáticos.Universidade Federal do Paraná Hospital de ClínicasUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade de Santiago do ChileUNIFESP, EPMSciEL
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