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The RNA Modification N^6-methyladenosine and Its Implications in Human Disease

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Genomics, Proteomics & Bioinformatics 2017年第3期15卷 154-163页

作者： pedro J.Batista Laboratory of Cell Biology Center for Cancer ResearchNational Cancer InstituteNational Institutes of HealthBethesda MD 20892USA

Impaired gene regulation lies at the heart of many disorders, including developmental diseases and cancer. Furthermore, the molecular pathways that control gene expression are often the target of cellular parasites, such as viruses. Gene expression is controlled through multiple mechanisms that are coordinated to ensure the proper and timely expression of each gene. Many of these mechanisms target the life cycle of the RNA molecule, from transcription to translation. Recently, another layer of regulation at the RNA level involving RNA modifications has gained renewed interest of the scientific community. The discovery that N6-methyladenosine （m6A）, a mod- ification present in mRNAs and long noncoding RNAs, can be removed by the activity of RNA demethylases, launched the field of epitranscriptomics; the study of how RNA function is regulated through the addition or removal of post-transcriptional modifications, similar to strategies used to regulate gene expression at the DNA and protein level. The abundance of RNA post-transcriptional modifications is determined by the activity of writer complexes （methylase） and eraser （RNA demethylase） proteins. Subsequently, the effects of RNA modifications materialize as changes in RNA structure and/or modulation of interactions between the modified RNA and RNA binding proteins or regulatory RNAs. Disruption of these pathways impairs gene expression and cellular function. This review focuses on the links between the RNA modification m6A and its implications in human diseases.

关键词： N6-methyladenosine Epitranscriptomics Cancer Viral replication Metabolic disease

Integrated Groups and Smooth Distribution Groups

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Acta Mathematica Sinica,English Series 2007年第1期23卷 57-64页

作者： pedro J.MIANA Departamento de Matemáticas Universidad de Zaragoza50009Spain

In this paper, we prove directly that α-times integrated groups define algebra homomorphisms. We also give a theorem of equivalence between smooth distribution groups and α-times integrated groups.

关键词： integrated groups distribution groups Weyl fractional calculus

Influence of bed elevation discordance on flow patterns and head losses in an open-channel confluence

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Water Science and Engineering 2019年第3期12卷 235-243页

作者： pedro Xavier Ramos Laurent Schindfessel Joao pedro Pego Tom De Mulder Department of Civil Engineering Ghent University Ghent 9000 Belgium Faculty of Engineering University of Porto Porto 4200-465 Portugal

Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is *** of schematized confluences with a step at the interface between the tributary and the main channel bed reveal that bed elevation discordance is an important additional control for the confluence *** study aimed to improve understanding of the influence of bed elevation discordance on the flow patterns and head losses in a right-angled confluence of an open channel with rectangular cross-sections.A large eddy simulation (LES)-based numerical model was set up and validated with experiments by *** configurations with different bed discordance ratios were *** results confirm that, with increasing bed elevation discordance, the tributary streamlines at the confluence interface deviate less from the geometrical confluence angle, the extent of the recirculation zone (RZ) gets smaller, the ratio of the water depth upstream to that downstream of the confluence decreases, and the water level depression *** bed elevation discordance also leads to the development of a large-scale structure in the lee of the *** the appearance of the large-scale structure, the reduced extent of the RZ and associated changes in flow deflection/contraction reduce total head losses experienced by the main channel with an increase of the bed discordance *** turns out that bed elevation discordance converts the lateral momentum from the tributary to streamwise momentum in the main channel more efficiently.

关键词： Open channel confluence Bed elevation discordance Three-dimensional numerical modelling Large eddy simulation Recirculation zone

Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico

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Frontiers in Energy 2019年第3期13卷 522-538页

作者： pedro PONCE Therese PEFFER Arturo MOLINA Tecnologico de Monterrey calle del puente 222 MexicoMexico CityNon-US/Non-Canadian 64849Mexico California Institute for Energy and Environment University of California BerkeleyBerkeleyCA 94720USA

It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes;thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词： thermostats perceptions beliefs signal detection theory (SDT) fuzzy signal detection theory (FSDT) chi-square (CS) test

Review of plant biogeographic studies in Brazil

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Journal of Systematics and Evolution 2009年第5期47卷 477-496页

作者： pedro FIASCHI José R.PIRANI Department of Biology Virginia Commonwealth University Departamento de Botanica Instituto de BiocienciasUniversidade de So Paulo

Molecular phylogenetic studies have become a major area of interest in plant systematics,and their impacts on historical biogeographic hypotheses are not to be *** Brazil,most historical biogeographic studies have relied on animal phylogenies,whereas plant biogeographic studies have largely lacked a phylogenetic component,having a limited utility for historical *** country,however,is of great importance for most biogeographic studies of lowland tropical South America,and it includes areas from a number of biogeographic regions of the *** biogeographic reports have been published as part of phylogenetic studies,taxonomic monographs,and regional accounts for small areas or phytogeographic domains,but the available information is subsequently scattered and sometimes hard to *** this paper we review some relevant angiosperm biogeographic studies in *** we briefly discuss the importance of other continents as source areas for the South American *** we present a subdivision of Brazil into phytogeographic domains,and we cite studies that have explored the detection of biogeographic units(areas of endemism) and how they are historically related among those *** of plant taxa that could be used to test some biogeographic hypotheses are provided throughout,as well as taxa that exemplify several patterns of endemism and disjunction in the Brazilian angiosperm flora.

关键词： angiosperms biogeography Brazil disjunction distribution patterns endemism.

A Study on Modeling and Optimization of Memory Systems

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Journal of Computer Science & Technology 2021年第1期36卷 71-89页

作者： Jason Liu pedro Espina Xian-He Sun School of Computing and Information Sciences Florida International UniversityMiamiFL 33199U.S.A Department of Computer Science Illinois Institute of TechnologyChicagoIL 60616U.S.A

Accesses Per Cycle(APC),Concurrent Average Memory Access Time(C-AMAT),and Layered Performance Matching(LPM)are three memory performance models that consider both data locality and memory assess *** APC model measures the throughput of a memory architecture and therefore reflects the quality of service(QoS)of a memory *** C-AMAT model provides a recursive expression for the memory access delay and therefore can be used for identifying the potential bottlenecks in a memory *** LPM method transforms a global memory system optimization into localized optimizations at each memory layer by matching the data access demands of the applications with the underlying memory system *** three models have been proposed separately through prior *** paper reexamines the three models under one coherent mathematical *** specifically,we present a new memorycentric view of data *** divide the memory cycles at each memory layer into four distinct categories and use them to recursively define the memory access latency and concurrency along the memory *** new perspective offers new insights with a clear formulation of the memory performance considering both locality and ***,the performance model can be easily understood and applied in engineering *** such,the memory-centric approach helps establish a unified mathematical foundation for model-driven performance analysis and optimization of contemporary and future memory systems.

关键词： performance modeling performance optimization memory architecture memory hierarchy concurrent average memory access time

One DOF mechanism for the mechanical harvest of vines in an arbor structure and the validation of the acceleration of grape berry harvesting

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Frontiers of Mechanical Engineering 2015年第3期10卷 221-232页

作者： pedro BOCCA Facultad de Ingenieria Universidad Nacional de San Juan San Juan5400 Argentina

In the mechanized harvest of vines, grape berries are detached through the vibration to the structure supporting the clusters. According to the kind of guide selected, the clusters require one or two vibration directions in the structure. For guiding in parral structures, vibration is necessary in two directions or planes： One perpendicular to the other. The guide branches producing the clusters develop in these planes, and the guiding is called H-guiding. Mechanism theory indicates that a mechanism has as many degrees of freedom as its actuators, and an actuator is needed to achieve a certain vibration. Having the smallest number of possible actuators is beneficial in reducing moving parts and achieving more compact and easily controllable mecha- nisms. In this case, a single degree-of-freedom mechanism is proposed. It is capable of generating vibrations on two planes： One perpendicular to the other. This mechanism is the sum of two link mechanisms on perpendicular planes with a common outlet located at the output rod of the mechanism where the actuator is found. As the distance between the soil and the elements containing the clusters is not constant, a system has been designed to measure the accelerations at the bars and the rocker to validate the acceleration values that detach the grape berries in a prototype in a lab experiment, to ensure that the acceleration needed for pulling the grape berries are produced at any contact point of the bar.

关键词： harvest mechanisms one DOF vibration

Necrotizing Pneumonia and Conservative Treatment: A Case Report and Review of the Literature

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Open Journal of Respiratory Diseases 2024年第3期14卷 69-76页

作者： pedro Rogerio Magalhães Braga Eduarda Kipper Beck Carolina de Mello Viera Cecília Gatti Wolff Laura Gazal Passos Guilherme Bastos de Mello Luis Felipe Pilar Gomes Giacomo Farias Tramontin Taíse Rosa de Carvalho Department of Internal Medicine Hospital So Lucas da PUCRS Porto Alegre Brazil School of Medicine Pontifcia Universidade Catlica do Rio Grande do Sul Porto Alegre Brazil Department of Radiology Hospital So Lucas da PUCRS Porto Alegre Brazil

We present a case of necrotizing pneumonia in an 87-year-old man without severe respiratory instability. Clinical suspicion arose due to the need for supplementary oxygen and persistent fever during treatment for community-acquired pneumonia. The diagnosis was confirmed by chest computed tomography. Although necrotizing pneumonia typically requires major surgical intervention upon diagnosis, we chose conservative management with antimicrobials and chest drainage alone. The patient experienced significant improvement and resolution of pneumonia with conservative management.

关键词： Respiratory Tract Infections Lung Disease Bacterial Pneumonia

High-Efficiency DC-DC Converter for Large Input-Voltage Fluctuations in Solar Applications

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Chinese Journal of Electronics 2015年第3期24卷 502-507页

作者： AGUILLON-GARCIA Jacobo BANUELOS-SANCHEZ pedro SIST Sun Yat-sen University

In the solar energy systems the solar irradiance variation is partially engaged, limiting the converter’s transformation rate for a certain input amount and leaving the rest of energy unconverted. In order to utilize at its maximum the energy provided from a Photovoltaic(PVP) system, this manuscript proposed a topology that can cope with marginal input voltage variations from 60V(DC) up to 1050V(DC) for a steady output voltage of 700V(DC). This output voltage value is suitable for any interlink post-regulation architecture. Based on previous observations, this paper presents a wide-input voltage high-efficiency non-isolated single-control topology. Analysis, operating stages, simulations and experimental results for a 3k W prototype are presented.

关键词： DC-DC power converters Energy conversion Photovoltaic system Power conditioning Solar generation