5,834 research outputs found

    Estudio del efecto del tamaĂąo en la estructura cristalina de nanopartĂ­culas de CoFe2O4

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    Se estudiĂł como afecta el tamaĂąo de nanopartĂ­culas de ferrita de cobalto en el desorden cristalino por efecto de superficie. Las nanopartĂ­culas se obtuvieron por el mĂŠtodo de coprecipitaciĂłn de sales. Para controlar el tamaĂąo realizaron diferentes tratamientos tĂŠrmicos posteriores a la sĂ­ntesis. La estructura cristalina y la morfologĂ­a se evaluaron por medio de DifracciĂłn de rayos-X y MicroscopĂ­a ElectrĂłnica de TransmisiĂłn de Alta ResoluciĂłn. Los resultados obtenidos demuestran en forma cuantitativa, cĂłmo la variaciĂłn en la relaciĂłn superficie/volumen es responsable de las deformaciones presentes en las nanoestructuras.Fil: Menchaca Nal, Sandra. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologia En Polimeros y Nanotecnologia; ArgentinaFil: LondoĂąo Calderon, Cesar Leandro. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologia En Polimeros y Nanotecnologia; ArgentinaFil: Pardo Saavedra, D. C.. Consejo Nacional de Investigaciones CientĂ­ficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de TecnologĂ­as y Ciencias de la IngenierĂ­a; ArgentinaFil: Pampillo, L. G.. Consejo Nacional de Investigaciones CientĂ­ficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de TecnologĂ­as y Ciencias de la IngenierĂ­a; ArgentinaFil: Socolovsky, Leandro Martin. Consejo Nacional de Investigaciones CientĂ­ficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de TecnologĂ­as y Ciencias de la IngenierĂ­a; ArgentinaFil: Martinez Garcia, Ricardo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologia En Polimeros y Nanotecnologia; Argentin

    Morfological study of pore widening process in anodized alumina films

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    Se estudiaron las caracterĂ­sticas morfolĂłgicas del proceso de ensanchamiento de poros en pelĂ­culas de alĂşmina (Al2O3) nanoporosa. El montaje experimental involucra un set-up de bajo costo que utiliza aluminio comercial. El procedimiento comprende una serie de pretratamientos, un proceso de doble anodizado, y finaliza con la inmersiĂłn de la nanoestructura porosa inicialmente fabricada, en una soluciĂłn acuosa de ĂĄcido sulfĂşrico durante diferentes intervalos de tiempo, que conduce a un ensanchamiento de poros. Se estudiĂł la morfologĂ­a de las muestras obtenidas por microscopia electrĂłnica de barrido, y sus principales propiedades (tamaĂąo, distribuciĂłn de tamaĂąo de poros, circularidad y porosidad) se evaluaron en funciĂłn del tiempo de ensanchamiento. Los resultados obtenidos sugieren una dependencia de la morfologĂ­a con el tiempo de exposiciĂłn de las nanoestructuras fabricadas. Estos resultados abren la posibilidad de fabricar nanoporos con propiedades ajustables y de bajo costo.We studied the morphological characteristics of the process of widening of pores in films of nanoporous alumina (Al2O3). The experimental setup involves a set-up that uses low cost commercial aluminum. The process comprises a series of pre-treatments, a double anodizing process, and ends with the immersion of the porous nanostructure (originally manufactured) in an aqueous solution of sulfuric acid, for different time intervals (pore widening). The morphology of the obtained samples was studied by scanning electron microscopy, and its main properties (size, pore size distribution, roundness and porosity) were evaluated as a function of the widening time. The results suggest a dependency of the exposure time with the morphology of the nanostructures fabricated. These results open the possibility of fabricating nanopores with adjustable properties and in an inexpensive way.Fil: Pardo Saavedra, D. C.. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de SĂłlidos Amorfos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de TecnologĂ­as y Ciencias de la IngenierĂ­a; ArgentinaFil: LondoĂąo Calderon, Cesar Leandro. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologia En Polimeros y Nanotecnologia; Argentina; Argentina. Universidad de Buenos Aires. Facultad de IngenierĂ­a; ArgentinaFil: Menchaca Nal, Sandra. Universidad de Buenos Aires. Facultad de IngenierĂ­a; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologia En Polimeros y Nanotecnologia; Argentina; ArgentinaFil: Pampillo, Laura Gabriela. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de SĂłlidos Amorfos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de TecnologĂ­as y Ciencias de la IngenierĂ­a; ArgentinaFil: Martinez Garcia, Ricardo. Universidad de Buenos Aires. Facultad de IngenierĂ­a; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologia En Polimeros y Nanotecnologia; Argentina; ArgentinaFil: Socolovsky, Leandro Martin. Consejo Nacional de Investigaciones CientĂ­ficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de TecnologĂ­as y Ciencias de la IngenierĂ­a; Argentina. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de SĂłlidos Amorfos; Argentin

    Effect of pretreatment with low-frequency ultrasound on quality parameters in gulupa (Passiflora edulis sims) pulp

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    The Gulupa (Passiflora edulis f. edulis Sims) is an expression of South America’s tropics’ biodiversity, and a source of B vitamins and amino acids. It is a climacteric export fruit for which it is necessary to incorporate emerging technologies for its conservation and transport. This work investigated the effect of ultrasound on gulupa pulp and verified the stability of the characters of interest in the shelf life of 20 days. Six treatments and a control sample were used, evaluated in triplicate, and varied in frequency (30 and 40 kHz) with an exposure time of 10, 20, and 30 min. A statistical analysis of unidirectional variances and Dunnett’s test was used. It was found that the ultrasound treatments did not affect the pH or the titratable acidity. Soluble solid results presented a significant increase (p < 0.05) (from 13.4 to 14.8% w/v) in the antioxidant capacity (from 1.13 to 1.54 µmol Trolox Equivalent (TE)/g by the ABTS•+ (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) Cationic Radical Assay and from 3.3 to 3.7 µmol TE/g by the DPPH· (2,2-diphenyl-1-picrilhydrazil) Radical Scavenging Assay). During the shelf life, ascorbic acid was the parameter that varied most (p < 0.05). It decreased from 42.7 to 21.6 mg ascorbic acid/100 g of pulp in the control sample. However, a smaller decrease was observed (23.8–24.5 mg ascorbic acid/100 g of pulp) in the 40 kHz treatments. The smallest global color difference (∆E) for the control was found in the 40 kHz treatment at 30 min through the entire shelf life (day 0 to 20). Ultrasound treatment offers a new strategy to improve and extend the shelf life of chilled gulupa pulp

    A completely-phased diploid genome assembly for ‘Malbec’ cultivar (Vitis vinifera L.)

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    Poster. Publicado en: BAG Journal of Basic and Applied Genetics, 32 (1 suppl), 2021Most grapevine cultivars originated from the outcrossing of two genetically diverse parents, and are clonally propagated to preserve phenotypes of productive interest. Hence, cultivars are first filial generations (F1) with highly heterozygous diploid genomes, that turn challenging to assemble. ‘Malbec’ is the main cultivar for the Argentine wine industry and it originated in France, from the outcrossing of ‘Magdeleine Noir des Charentes’ and ‘Prunelard’ cultivars. Based on that mother-father-offspring relationship, here we followed the algorithm implemented in the software CanuTrio to produce a phased assembly of ‘Malbec’ genome. For this aim, parental cultivars’ Illumina short-reads were used to sort ‘Malbec’ PacBio long-reads into its haploid complements, to be assembled separately. Postassembly, bioinformatic procedures were employed to reduce the number of duplicated regions and perform sequence error corrections (using ‘Malbec’ Illumina short-reads). We obtained two highly complete and contiguous haploid assemblies for ‘Malbec’, Haplotype-Prunelard (482.4 Mb size; contig N50=7.7 Mb) and Haplotype-Magdeleine (479.4 Mb size; contig N50=6.6 Mb), with 96.1 and 95.8% of BUSCO genes, respectively. We tested for the composition of both haplophases with the tool Merqury, and observed 15% of both assemblies affected by structural variations, along with 3.2 million SNPs and 0.6 million InDels. Our results indicate that this is a valid approach to assemble highly heterozygous and complex diploid genomes in a completely-phased way.EEA MendozaFil: Calderón, Luciano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Carbonell-Bejerano, P. Max Planck Institute for Developmental Biology; AlemaniaFil: Mauri, Nuria. Instituto de Ciencias de la Vid y del Vino (CSIC, UR, Gobierno de La Rioja). Finca La Grajera; ArgentinaFil: Muñoz, C. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Bree, Laura. Vivero Mercier; ArgentinaFil: Sola, Cristóbal. Vivero Mercier; ArgentinaFil: Bergamin, Daniel. Vivero Mercier; ArgentinaFil: Gomez Talquenca, Gonzalo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Martínez Zapater, José Miguel. Instituto de Ciencias de la Vid y del Vino (CSIC, UR, Gobierno de La Rioja). Finca La Grajera; ArgentinaFil: Weigel, D. Max Planck Institute for Developmental Biology; AlemaniaFil: Lijavetzky, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentin

    Analysis of results of effective dose estimation obtained from RADAR 2017 dose assessment model for nuclear medicine procedures

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    EP-296 Aim/Introduction: To analyze the results of effective dose (E) estimation of the most frequent procedures using photon emitters in Nuclear Medicine, obtained from RADAR 2017 dose assessment model. To compare these results with those obtained from ICRP 128 (2015) recommendations, and to assess how using each dose assessment model can change E results. Materials and Methods: E estimation data was collected from photon emitter procedures performed during the last year in our department, obtained from RADAR 2017 dose estimation model for age groups: = 1 year old; >1-5 years old ; >5- 10 years old, >10- 15 years old and adults. Injected activity was the one recommended by international guidelines and EANM Pediatric and Dosimetry Committees. Hybrid exams (SPECT / CT) and procedures for which there is no RADAR 2017 dosimetry estimation were excluded. Results for (E) were compared with those obtained by using ICRP 128 (2015) recommendations. Results: With RADAR 2017 dose evaluation model we obtained a lower mean value of E on most of the procedures that were analyzed, being significantly lower for Renogram, Renal scintigraphy on >10-15 years old, Thyroid scintigraphy, Meckel’s scan and Bone Scan (0.12 to 1.16 mSv, 25% to 67%). Brain perfusion and Renal scintigraphy on ages under 10 obtained a significantly greater difference for E (0.33 to 2.85 mSv, 26% to 29%). Conclusion: These results are an updated collection of estimated E values for photon-emitting radiopharmaceuticals commonly used in Nuclear Medicine, considering RADAR 2017 dose assessment model compared to ICRP 128) recommendations. Methodological changes on estimation lead to lower E for most of diagnostic procedures using photon emitters, this is of special interest for patients undergoing repeated ionizing radiation (dosimetry history)

    Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

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    A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets

    Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

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    A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE
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