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Communications and Network 2013年第3期5卷 498-503页

作者： Pablo Briff Leonardo Rey vega Ariel Lutenberg Fabian Vargas Embedded Systems Laboratory Faculty of Engineering University of Buenos Aires Argentina Signal Processing and Communications Laboratory Faculty of Engineering University of Buenos Aires Argentina Signals and Systems for Computing Group Faculty of Engineering Catholic University PUCRS Brazil

In this work we find a lower bound on the energy required for synchronizing moving sensor nodes in a Wireless Sensor Network (WSN) affected by large-scale fading, based on clock estimation techniques. The energy required for synchronizing a WSN within a desired estimation error level is specified by both the transmit power and the required number of messages. In this paper we extend our previous work introducing nodes’ movement and the average message delay in the total energy, including a comprehensive analysis on how the distance between nodes impacts on the energy and synchronization quality trade-off under large-scale fading effects.

关键词： Wireless Sensor Networks Clock Offset Estimation Time Synchronization Wireless Channel Fading Moving Targets

On Energy-Efficient Time Synchronization for Wireless Sensors under Large-Scale and Small-Scale Fading Effects

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Wireless Sensor Network 2013年第10期5卷 181-193页

作者： Pablo Briff Ariel Lutenberg Leonardo Rey vega Fabian Vargas CONICET National Scientific and Technical Research Council Buenos Aires Argentina LPSC Faculty of Engineering University of Buenos Aires Buenos Aires Argentina Embedded Systems Laboratory Faculty of Engineering University of Buenos Aires Buenos Aires Argentina Embedded Systems Laboratory Faculty of Engineering University of Buenos Aires Buenos Aires Argentina CONICET National Scientific and Technical Research Council Buenos Aires Argentina Signals and Systems for Computing Group Faculty of Engineering Catholic University Porto Alegre Brazil

In this work, the existing trade-off between time synchronization quality and energy is studied for both large-scale and small-scale fading wireless channels. We analyze the clock offset estimation problem using one-way, two-way and N-way message exchange mechanisms affected by Gaussian and exponentially distributed impairments. Our main contribution is a general relationship between the total energy required for synchronizing a wireless sensor network and the clock offset estimation error by means of the transmit power, number of transmitted messages and average message delay, deriving the energy optimal lower bound as a function of the time synchronization quality and the number of hops in a multi-hop network.

关键词： Wireless Sensor Networks Clock Offset Estimation Time Synchronization Wireless Channel Fading

Biocomposites Based on Thermoplastic Starch and Granite Sand Quarry Waste

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Journal of Renewable Materials 2019年第4期7卷 393-402页

作者： María G.Passaretti Mario D.Ninago Cecilia I.Paulo Horacio A.Petit Edgardo F.Irassarc Daniel A.vega Marcelo A.Villar Olivia V.López Planta Piloto de Ingeniería Química PLAPIQUI(UNS-CONICET)Camino"La Carrindanga"Km 7Bahía Blanca8000Buenos AiresArgentina Departamento de Ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca8000Buenos AiresArgentina Facultad de Ciencias Aplicadas a la Industria(FCAI) Universidad Nacional de Cuyo(UNCuyo)Bernardo de Irigoyen 375San Rafael5600MendozaArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Godoy Cruz 2290Ciudad Autónoma de Buenos AiresC1425FQBBuenos AiresArgentina Facultad de Ingeniería Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPBA).Centro de Investigaciones en Física e IngenieríaCIFICEN(UNCPBA-CICPBA-CONICET)7400OlavarríaArgentina Instituto de Física del Sur IFISUR(UNS-CONICET)Bahía Blanca8000Argentina

Granite stone is a by-product of the rock crushing *** industrial waste in powder form that causes health problems and environmental *** particles fraction can be used as a partial replacement of sand in concrete *** this work,an alternative exploitation of this waste fraction is *** sand(GS)with particles mean size of ~1μm was employed as thermoplastic starch(TPS)filler at different *** were obtained by melt-mixing and thermo-compression,achieving translucent and easy to handle films.A good GS dispersion within the matrix was evidenced by *** presence induced a shift of starch’s melting point to higher values and a better thermal *** UV absorption capacity was increased ~90% by GS *** increment in TPS Young’s modulus and maximum tensile stress of 5 and 3 times,respectively was observed by adding 5%w/w GS.

关键词： Thermoplastic starch granite sand melt processing final properties

Statistical Approach to Regulation of Nanotechnology:Need,Advantages and Disadvantages

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Journal of Biomaterials and Nanobiotechnology 2020年第1期11卷 14-32页

作者： Ricardo Santana Cabello Jose vega-Baudrit Robin Zuluaga Piedad Ganan Deusto Institute of Technology(Deusto Tech) University of DeustoBilbaoSpain New Materials Research Group Universidad Pontificia BolivarianaMedellinColombia National Laboratory of Nanotechnology LANOTEC-CENAT-CONARE PavasSan JoseCosta Rica POLIUNA Chemistry SchoolNational UniversityHerediaCosta Rica Faculty of Agro-Industrial Engineering Universidad Pontificia BolivarianaMedellinColombia Faculty of Chemical Engineering Universidad Pontificia BolivarianaMedellinColombia

The need to have an express regulation covering nanotechnology has been the subject of debate in the scientific literature and identified as one of the main subsets of nanotechnology field research. However, most countries still do not have regulatory framework in order to guarantee consumer safety. This is the case of Costa Rica, one of the most promising countries in Latin America in terms of biotechnology and nanotechnology. This article presents a statistical study about the position of industry, academia and government institutions on the need to expressly regulate nanotechnology in Costa Rica. A qualitative study consisting of a survey of 79 forms was done to individuals representing the community involved with nanotechnology and institutions responsible for ensuring the safety of the citizen’s health, to conclude that the nanotechnology regulation should be created to protect the consumer in Costa Rica. The research also proposes aspects that should be taken into account in its drafting as well as the variables on which decisions should be made to authorize the commercialization of nanomaterials based on the findings of the literature.

关键词： Nanotechnology Regulation Security Consumer

Effect of Ligands to Toll-Like Receptors (TLR) 3, 7 and 9 on Mice Infected with Mouse Hepatitis Virus A59

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Open Journal of Immunology 2014年第4期4卷 129-138页

作者： José L. Aparicio Maite Duhalde vega Lilia A. Retegui Institute of Biochemistry and Biophysics (IQUIFIB UBA-CONICET) School of Pharmacy and Biochemistry University of Buenos Aires Buenos Aires Argentina

Mice infected with mouse hepatitis virus A59 (MHV-A59), an enveloped, positive-strand RNA Co-ronavirus, induce hepatitis, thymus involution, IgG2a-restricted hypergammaglobulinaemia, transaminase release and autoantibodies (autoAb) to liver and kidney fumarylacetoacetate hy-drolase (FAH). Since Toll-like receptors (TLR) play a central role in innate immunity, we explored the effects of TLR3, 7 and 9 stimulation on MHV mouse infection. Thus, the animals were treated with Poly (I:C), Loxoribine and CpG, the respective TLR ligands. MHV-infected mice inoculated with Poly (I:C) had significant lower levels of plasma transaminases and Ig, anti-MHV Ab, and uric acid than MHV-infected animals, whereas autoAb to kidney tissue were observed. Loxoribine only produced a slight decrease of uric acid levels and serum Ig. CpG showed deleterious effects on MHV-infected mice, since survival of animals dramatically dropped to about 10%. AutoAb to murine tissues and uric acid release were not affected, whereas transaminases and anti-MHV Ab were slightly elevated. Besides, CpG administration produced a decrease of the high levels of serum Ig induced by the virus. Therefore, results indicated that TLR3 stimulation appeared to protect the animals against the viral infection, whereas CpG aggravated its signs. Loxoribine, the TLR7 ligand, did not show major effects.

关键词： Mouse Hepatitis Virus Toll-Like Receptors Autoantibodies Uric Acid

Human Long Telomeres and Epigenetic Marks

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CellBio 2013年第2期2卷 70-72页

作者： María I. Vaquero-Sedas Miguel A. vega-Palas Instituto de Bioquímica Vegetal y Fotosíntesis Universidad de Sevilla-CSIC Seville Spain

We have read with interest the article “Telomere length regulates TERRA levels through increased trimethylation of telomeric H3K9 and HP1α” by Arnoult and colleagues [1]. This study focuses on human telomeric chromatin structure using different techniques like Chromatin Immunoprecipitation (ChIP), cytolocalization or RT-qPCR. However, it has been performed without taking into consideration the presence of Interstitial Telomeric Sequences (ITSs) in the human genome. Some of the conclusions of the article are undoubtedly clear but there are others that might be explained in alternative ways, considering the existence of ITSs. Following, we mention some comments that arise from this interesting article.

关键词： Telomeres TERRA Epigenetics Human

The restriction endonuclease Tru9I is a useful tool to analyze telomere sequences separately from interstitial telomeric sequences in <i>Arabidopsis thaliana</i>

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American Journal of Molecular Biology 2012年第3期2卷 242-244页

作者： María I. Vaquero-Sedas Miguel A. vega-Palas Instituto de Bioquímica Vegetal y Fotosíntesis CSIC-Universidad de Sevilla Seville Spain

We have previously described a simple method to analyze the chromatin structure of Arabidopsis telomeres independently of that of Interstitial Telomeric Sequences (ITSs). By using this method, we found that, whereas ITSs are heterochromatic, Arabidopsis telomeres exhibit euchromatic features [1]. Some concerns have been recently raised about the accuracy of this procedure [2]. Here, we summarize these concerns and justify our experimental approaches and interpretation of results.

关键词： Arabidopsis thaliana telomeres ITSs euchromatin heterochromatin

The Genome of Cucurbita argyrosperma (Silver- Seed Gourd) Reveals Faster Rates of Protein- Coding Gene and Long Noncoding RNA Turnover and Neofunctionalization within Cucurbita

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Molecular Plant 2019年第4期12卷 506-520页

作者： Josue Barrera-Red on do Enrique Ibarra-Laclette Alejandra Vazquez-Lobo Yocelyn T. Gutierrez-Guerrero Guillermo Sanchez de la vega Daniel Pinero Salvador Montes-Hernandez Rafael Lira-Saade Luis E. Eguiarte Departamento de Ecologia Evolutiva Instituto de Ecologia Universidad Nacional Aut6noma de Mexico Circuito Exterior s/n Anexo al Jardin Bot合nico 04510 Ciudad de Mexico Mexico Departamento de Estudios Moleculares Avanzados Instituto de Ecologia A.C. Carretera Antigua a Coatepec No. 351 Col. El Haya. C.P. Xalapa Veracruz 91070 Mexico Centro de Investigaciones en Biodiversidad y Conservacion Universidad Autdnoma del Estado de Morelos Av. Universidad 1001 Col. Chamilpa Cuernavaca Morelos 62209 Mexico Campo Experimental Bajio Instituto Nacional de In vestigaciones Forestales Agricolas y Pecuarias (INIFAP) Km 6.5 Carretera Celaya-San Miguel de Allen de Celaya Guanajuato 38110 Mexico UBIPRO Facultad de Estudios Superiores Iztacala Universidad Nacional Autdnoma de Mexico Av. de los Barrios #1 Col. Los Reyes Iztacala Tlanepantla Edo. de Mex 54090 Mexico

Whole-genome duplications are an important source of evolutionary novelties that change the mode and tempo at which genetic elements evolve within a genome. The Cucurbita genus experienced a wholegenome duplication around 30 million years ago, although the evolutionary dynamics of the coding and noncoding genes in this genus have not yet been scrutinized. Here, we analyzed the genomes of four Cucurbita species, in eluding a newly assembled genome of Cucurbita argyrosperma, and compared the gene con tents of these species with those of five other members of the Cucurbitaceae family to assess the evolutionary dynamics of protein-coding and long intergenic noncoding RNA (lincRNA) genes after the genome duplication. We report that Cucurbita genomes have a higher protein-coding gene birth-death rate compared with the genomes of the other members of the Cucurbitaceae family. C. argyrosperma gene families associated with pollination and transmembrane transport had significantly faster evolutionary rates. lincRNA families showed high levels of gene turnover throughout the phylogeny, and 67.7% of the lincRNA families in Cucurbita showed evidence of birth from the neofunctionalization of previously existing protein-coding genes. Collectively, our results suggest that the whole-genome duplication in Cucurbita resulted in faster rates of gene family evolution through the neofunctionalization of duplicated genes.

关键词： Cucurbita argyrosperma, comparative genomics molecular evolution neofunctionalization long noncoding RNA whole-genome duplication

Comparisons of the Properties of Whitemouth Croaker (<i>Micropogonias furnieri</i>) Surimi and Mechanically Deboned Chicken Meat Surimi-Like Material

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Food and Nutrition Sciences 2012年第11期3卷 1480-1483页

作者： William Renzo Cortez-vega Gustavo Graciano Fonseca Carlos Prentice Laboratory of Bioengineering Faculty of Engineering Federal University of Grande Dourados Dourados Brazil. Laboratory of Food Technology School of Chemistry and Foods Federal University of Rio Grande Rio Grande Brazil

The aim of this work was to evaluate and compare the color, texture and sensory characteristics of whitemouth croaker (Micropogonias furnieri) surimi and mechanically separated chicken meat (MDCM) surimi-like material (SLM). The whiteness of the MDCM-SLM was higher (P > 0.05) than that from the surimi. Higher breaking force (P 0.05). The MDCM-SLM was more accepted by the panelists (P < 0.05). The mean scores of overall desirability for MDCM-SLM was similar to that observed for walleye Pollack surimi that is the parameter of quality. The differences in the acceptability of poultry and fish food products are probably due to peoples’ eating habits.

关键词： Fish Chicken Surimi-Like Material Whiteness Texture Sensory

Frequently cutting restriction enzymes: Clearing the fog to see the ends

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American Journal of Molecular Biology 2013年第1期3卷 59-61页

作者： María I. Vaquero-Sedas Miguel A. vega-Palas Institute of Vegetal Biochemistry and Photosynthesis CSIC-University of Seville Seville Spain

Telomeres, which are found at the ends of eukaryotic chromosomes, are composed of tandem arrays of repetitive sequences and safeguard genomic stability. Previous studies have revealed that telomeric repeats are also present at internal chromosomal loci in many eukaryotes. However, the biological role of these interstitial telomeric sequences (ITSs) remains unknown. The integrity of telomeric length and chromatin structure is required for telomere stability. However, the study of these telomeric features can be impeded by the presence of ITSs. Frequently cutting restriction enzymes have been revealed to be very useful tools for the study of the length and chromatin structure of telomeres independent of the presence of ITSs.

关键词： Telomeric Length Telomeric Chromatin Structure Frequently Cutting Restriction Enzymes Arabidopsis thaliana