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Artigo Acesso aberto Revisado por pares

Álvaro Peña, Kamil Gewartowski, Seweryn Mroczek, Jorge Cuéllar, A. Szykowska, Andrzej Prokop, Mariusz Czarnocki‐Cieciura, Jan Piwowarski, Cristina Tous, Andrés Aguilera, José L. Carrascosa, José Valpuesta, Andrzej Dziembowski,

... of the THO complex, an mRNP assembly factor Álvaro Peña Álvaro Peña Department of Structure of Macromolecules, Centro Nacional de ... Poland Search for more papers by this author Álvaro Peña Álvaro Peña Department of Structure of Macromolecules, Centro Nacional de ...

Tópico(s): RNA and protein synthesis mechanisms

2012 - Springer Nature | The EMBO Journal

Artigo Acesso aberto Revisado por pares

Álvaro Peña, Daniel Matatagui, Filiberto Ricciardella, Leandro Sacco, Sten Vollebregt, Daniel Otero, Jesús López‐Sánchez, Pilar Marín, M.C. Horrillo,

Nitrogen dioxide (NO2) is a potential hazard to human health at low concentrations, below one part per million (ppm). NO2 can be monitored using gas sensors based on multi-layered graphene operating at ambient temperature. However, reliable detection of concentrations on the order of parts per million and lower is hindered by partial recovery and lack of reproducibility of the sensors after exposure. We show how to overcome these longstanding problems using ultraviolet (UV) light. When exposed to NO2, ...

Tópico(s): Graphene research and applications

2022 - Elsevier BV | Applied Surface Science

Artigo Acesso aberto Revisado por pares

A. Srinath, Álvaro Pena López, Seyed Alireza Miran Fashandi, Sylvain Lechat, Giampiero di Legge, Seyed Ali Nabavi, Theoklis Nikolaidis, Soheil Jafari,

The thermal management system architectures proposed for hydrogen-powered propulsion technologies are critically reviewed and assessed. The objectives of this paper are to determine the system-level shortcomings and to recognise the remaining challenges and research questions that need to be sorted out in order to enable this disruptive technology to be utilised by propulsion system manufacturers. Initially, a scientometrics based co-word analysis is conducted to identify the milestones for the ...

Tópico(s): Advanced Combustion Engine Technologies

2022 - Multidisciplinary Digital Publishing Institute | Energies

Artigo Revisado por pares

Rodrigo Pulgar, Dinka Mandaković, Pablo Salgado, Lucas Venegas, Daniela Ortiz, Álvaro Peña‐Neira, Jurij Wacyk,

The salmon industry has reduced fishmeal in aquafeeds with different sources of alternative proteins, including low-cost plant meals. However, high replacement levels cause negative impacts on carnivore salmonids' growth, partly explained by alterations in the inflammatory and antioxidant response. To cope with this situation, we evaluated the effect of a dietary polyphenol supplementation of micro-encapsulated grape pomace extract (MGPE) from wine industry residual by-product in a diet high in soybean ...

Tópico(s): Aquatic life and conservation

2021 - Elsevier BV | Aquaculture

Artigo Revisado por pares

Daniel Matatagui, Jesús López‐Sánchez, Álvaro Peña, Aída Serrano, Adolfo del Campo, O. Rodrı́guez de la Fuente, N. Carmona, E. Navarro, Pilar Marín, M.C. Horrillo,

Few-layered mesoporous graphene (FLMG) is employed as a sensing material to develop an innovative and high-sensitivity room temperature NO2 sensor through a simple manufacturing process. For this purpose, sensing material is optimized at 100 min by a high-energy milling process where natural graphite is used as a precursor: it is an inexpensive, sustainable and suitable active material. The large number of defects created and the enhanced degree of mesoporosity produced during the milling process ...

Tópico(s): Electrochemical sensors and biosensors

2021 - Elsevier BV | Sensors and Actuators B Chemical

Artigo

Mariona Gil, Cristina Úbeda, José Ignacio Covarrubias, Álvaro Peña‐Neira,

The use of vessels that are alternative to conventional cylindrical stainless steel tanks and traditional oak barrels during winemaking has increased in recent years. Examples of these alternative vessels include fashionable, oval-shaped vessels or classic clay jars. A Sauvignon blanc grape juice was fermented (by using a commercial starter made of two different commercial strains from Oenobrands/Anchor Oenology) in four different vessels in triplicate: 150 L cylindrical stainless steel tanks (as ...

Tópico(s): Wine Industry and Tourism

2020 - Elsevier BV | Innovative Food Science & Emerging Technologies

Artigo Acesso aberto Revisado por pares

Lucía Michel, Álvaro Peña‐Neira, Claudio Pastenes, Pablo Berríos, Adamo Domenico Rombolà, José Ignacio Covarrubias,

The aim of this investigation was to study the effect of sustainable strategies to correct iron deficiency in blueberries, based on Fe-heme applications or intercropping with graminaceous species, on yield and berry quality variables. The experiment was conducted in a blueberry orchard established in a sub-alkaline soil. The association with grasses increased the crop load and yield (only Festuca rubra), and decreased the skin/flesh ratio. In addition, these treatments increased anthocyanins as well ...

Tópico(s): Postharvest Quality and Shelf Life Management

2019 - Frontiers Media | Frontiers in Plant Science

Artigo Revisado por pares

Camila Cárdenas Moren, Kathleen Crawford Augant, Broderick Crawford, Ricardo Soto de Giorgis, Hanns de la Fuente‐Mella, Álvaro Peña, Matías Valenzuela Saavedra, Pamela Hermosilla Monckton, Lorena Álvarez Castelli,

This study focuses on identifying personality traits in engineering students and testing whether they are related to academic performance. In addition, the importance of the personality construct in the educational and vocational training context was studied. A sample of 235 students from the Construction Engineering and Computer Engineering Schools of the Pontifical Catholic University of Valparaíso was used. Through correlation and econometrics analysis, the results obtained indicate that there ...

Tópico(s): Diverse Applied Research Studies

2019 - Routledge | Studies in Higher Education

Artigo Acesso aberto Revisado por pares

José García, Paola Moraga, Matías A. Valenzuela, Broderick Crawford, Ricardo Soto, Hernán Pinto, Álvaro Peña, Francisco Altimiras, Gino Astorga,

The integration of machine learning techniques and metaheuristic algorithms is an area of interest due to the great potential for applications. In particular, using these hybrid techniques to solve combinatorial optimization problems (COPs) to improve the quality of the solutions and convergence times is of great interest in operations research. In this article, the db-scan unsupervised learning technique is explored with the goal of using it in the binarization process of continuous swarm intelligence ...

Tópico(s): Optimization and Packing Problems

2019 - Hindawi Publishing Corporation | Computational Intelligence and Neuroscience

Artigo Revisado por pares

Cristina Úbeda, Ingeborg Kania-Zelada, Rubén del Barrio‐Galán, Marcela Medel‐Marabolí, Mariona Gil, Álvaro Peña‐Neira,

One of the strongest factors that affects the volatile profile of sparkling wine is the winemaking process. Here we focus on determining the effects of the second fermentation and aging on lees of sparkling wine from País grape variety combining different analysis techniques for the first time in sparkling wine: gas chromatography/mass spectrometry/olfactometry and sensorial analysis. During the second fermentation and aging, there was a significant loss of esters that might be related to the adsorption ...

Tópico(s): Biochemical and biochemical processes

2018 - Elsevier BV | Food Research International

Artigo Acesso aberto Revisado por pares

José García, Francisco Altimiras, Álvaro Peña, Gino Astorga, Óscar Peredo,

The progress of metaheuristic techniques, big data, and the Internet of things generates opportunities to performance improvements in complex industrial systems. This article explores the application of Big Data techniques in the implementation of metaheuristic algorithms with the purpose of applying it to decision‐making in industrial processes. This exploration intends to evaluate the quality of the results and convergence times of the algorithm under different conditions in the number of solutions ...

Tópico(s): Metaheuristic Optimization Algorithms Research

2018 - Hindawi Publishing Corporation | Complexity

Artigo Acesso aberto Revisado por pares

Jaime Laqui‐Estaña, Remigio López‐Solís, Álvaro Peña‐Neira, Marcela Medel‐Marabolí, Elías Obreque‐Slier,

This study characterized the flavonoid and nonflavonoid phenolic composition of Carménère and Cabernet Sauvignon wines that were in contact with barrels, chips, and staves during a 12 month aging period. The wines were evaluated by spectrophotometric (for total phenols, anthocyanins and tannins, colorant intensity, hue, CIELab parameters, and fractionation into mono-, oligo-, and polymers of proanthocyanidins) and high-performance liquid chromatography diode array detection analyses (for ellagitannins, ...

Tópico(s): Phytochemicals and Antioxidant Activities

2018 - Wiley | Journal of the Science of Food and Agriculture

Artigo Revisado por pares

Inmaculada Talaverano, Cristina Úbeda, Alejandro Cáceres‐Mella, Marı́a Valdés, Claudio Pastenes, Álvaro Peña‐Neira,

Controlled water deficits affect grape berry physiology and the resulting wines, with volatile composition being the one of the affected parameters. However, there is a potential disconnect between aromatic maturity and sugar accumulation. Accordingly, the effects of three different water status levels over two growing seasons (2014 and 2015) and two different harvest dates on the aroma compounds from Cabernet Sauvignon wines were studied. Volatile compounds were determined using headspace solid ...

Tópico(s): Plant biochemistry and biosynthesis

2017 - Wiley | Journal of the Science of Food and Agriculture

Artigo Revisado por pares

Marcela Medel‐Marabolí, J.L. Romero, Elías Obreque‐Slier, Ángela Contreras, Álvaro Peña‐Neira,

Astringency is a tactile sensation that is generated by a reduction in lubrication in the oral cavity and is generally attributed to the interaction of procyanidins or condensed tannins with salivary proteins. Several factors influence tannin-protein interactions, such as pH, alcohol, sweetness, oxygen and polyphenol content. A scarcely studied factor is the effect of the tannin content on the perception of astringency. The objective of this study was to evaluate the effect of different concentrations ...

Tópico(s): Horticultural and Viticultural Research

2017 - Elsevier BV | Food Research International

Artigo Revisado por pares

Cristina Úbeda, Rubén del Barrio‐Galán, Álvaro Peña‐Neira, Marcela Medel‐Marabolí, Enrique Durán,

The aromatic profile of monovarietal Carignan wine has been characterized, and the influence of the geographic origin of the wine on the volatile composition wines from six different zones of Chile and from two different seasons has been studied. The solid-phase microextraction conditions employed were previously studied. An extraction temperature of 45°C, 40 min of incubation, 1.5 g of salt, and 180 sec of fiber desorption were employed for the analysis of the 28 wine samples studied. Sixty-three ...

Tópico(s): Wine Industry and Tourism

2017 - American Society for Enology and Viticulture | American Journal of Enology and Viticulture

Artigo Revisado por pares

Gina Vazallo-Valleumbrocio, Marcela Medel‐Marabolí, Álvaro Peña‐Neira, Remigio López‐Solís, Elías Obreque‐Slier,

The effect of the addition of different commercial enological tannins (CETs) on the characteristics of Carménère red wine was evaluated. Initially, chemical characterization of eleven CETs was performed using spectrophotometric and HPLC-DAD techniques. Then, the effects of six CETs on the properties of a Carménère wine during bottle storage (90 days) were evaluated for up to 90 days. Four CETs from wood exhibited highly variable phenolic compositions and the highest values of hydrolyzable tannins ...

Tópico(s): Phytochemicals and Antioxidant Activities

2017 - Elsevier BV | LWT

Artigo Acesso aberto Revisado por pares

Amy C. Degnim, Tanya L. Hoskin, Muhammad Usman Arshad, Marlene H. Frost, Stacey J. Winham, Rushin Brahmbhatt, Alvaro Peña, Jodi M. Carter, Melody Stallings‐Mann, Linda M. Murphy, Erin Miller, Lori A. Denison, Celine M. Vachon, Keith L. Knutson, Derek C. Radisky, Daniel W. Visscher,

Purpose: Little is known about the role of the immune system in the earliest stages of breast carcinogenesis. We studied quantitative differences in immune cell types between breast tissues from normal donors and those from women with benign breast disease (BBD).Experimental Design: A breast tissue matched case-control study was created from donors to the Susan G. Komen for the Cure Tissue Bank (KTB) and from women diagnosed with BBD at Mayo Clinic (Rochester, MN) who either subsequently developed ...

Tópico(s): Immunotherapy and Immune Responses

2017 - American Association for Cancer Research | Clinical Cancer Research

Artigo Acesso aberto Revisado por pares

Rodrigo Loyola, Daniela P. Herrera, Abraham Más, Darren C. J. Wong, Janine Höll, Erika Cavallini, Alessandra Amato, Akifumi Azuma, Tobias Ziegler, Felipe Aquea, Simone D. Castellarin, Jochen Bogs, Giovanni Battista Tornielli, Álvaro Peña‐Neira, Stefan Czemmel, José Antonio Alcalde, José Tomás Matus, Patricio Arce‐Johnson,

Grapevine (Vitis vinifera L.) is a species well known for its adaptation to radiation. However, photomorphogenic factors related to UV-B responses have not been molecularly characterized. We cloned and studied the role of UV-B RECEPTOR (UVR1), ELONGATED HYPOCOTYL 5 (HY5), and HY5 HOMOLOGUE (HYH) from V. vinifera. We performed gene functional characterizations, generated co-expression networks, and tested them in different environmental conditions. These genes complemented the Arabidopsis uvr8 and hy5 ...

Tópico(s): Photosynthetic Processes and Mechanisms

2016 - Oxford University Press | Journal of Experimental Botany

Artigo Acesso aberto

Mariela Labbé, Pablo A. Ulloa, Francisco López, Carmen Sáenz, Álvaro Peña‐Neira, Fernando N. Salazar,

In recent years, pomegranate (Punica granatum L.) fruit has gained popularity due to its functional properties.In this study, the effects of maturity on the chemical composition (pH, acidity and total soluble solids), total phenolic contents, anthocyanin contents and antioxidant capacities of pomegranate juices from three varieties (Wonderful, Chaca and Codpa) were assessed.The fruits were collected manually at three maturity stages (M1: unripe, M2: medium ripe, and M3: full ripe) from the Region de ...

Tópico(s): Plant Physiology and Cultivation Studies

2016 - Instituto de Investigaciones Agropecuarias, INIA | Chilean journal of agricultural research

Artigo Acesso aberto Revisado por pares

Cristina Úbeda, Raquel M. Callejón, Ana M. Troncoso, Álvaro Peña‐Neira, M. Lourdes Morales,

The volatile compositions of Charmat and traditional Chilean sparkling wines were studied for the first time. For this purpose, EG-Silicone and PDMS polymeric phases were compared and, afterwards, the most adequate was selected. The best extraction method turned out to be a sequential extraction in the headspace and by immersion using two PDMS twisters. A total of 130 compounds were determined. In traditional Chilean sparkling wines, ethyl esters were significantly higher, while acetic esters and ...

Tópico(s): Horticultural and Viticultural Research

2016 - Elsevier BV | Food Chemistry

Artigo Revisado por pares

Luis Villalobos-González, Álvaro Peña‐Neira, Freddy Ibáñez, Claudio Pastenes,

ABA has been proposed as the main signal triggering the onset of the ripening process in grapes, and modulating the secondary metabolism in grape berry skins. To determine the effect of ABA on secondary metabolism in berries, clusters of Carménère were sprayed with 0 μLL(-1) ABA; 50 μLL(-1) ABA and 100 μLL(-1) ABA during pre-véraison, and the gene expression of the transcription factors and enzymes of the phenylpropanoid pathway were assessed from véraison to 70 days after véraison (DAV). Additionally, ...

Tópico(s): Plant Gene Expression Analysis

2016 - Elsevier BV | Plant Physiology and Biochemistry

Artigo Revisado por pares

Tamara Fernandez‐Calero, Rosa Garcia-Silva, Álvaro Peña‐Neira, Carlos Robello, Helena Persson, Carlos Rovira, Hugo Naya, Alfonso Cayota,

Over the last years, an expanding family of small regulatory RNAs (e.g. microRNAs, siRNAs and piRNAs) was recognized as key players in novel forms of post-transcriptional gene regulation in most eukaryotes. However, the machinery associated with Ago/Dicer-dependent small RNA biogenesis was thought to be either entirely lost or extensively simplified in some unicellular organisms including Trypanosoma cruzi, Saccharomyces cerevisiae, Leishmania major and Plasmodium falciparum. Although the biogenesis ...

Tópico(s): Parasites and Host Interactions

2015 - Elsevier BV | Molecular and Biochemical Parasitology

Artigo Revisado por pares

Álvaro Peña‐Neira, Montserrat Dueñas, Arthur Franco Teodoro Duarte, T. Hernández, Isabel Estrella, Eduardo Loyola,

Quantitative changes in the composition of phenolic compounds in skins and seeds were determined during ripening of grape of Cabernet Sauvignon vines growing with low, medium or high vigor. Compounds in the skins were gallic and syringic acid, (+)-catechin, (-)-epicatechin, quercetin-3-galactoside, quercetin-3-rutinoside, quercetin-3-arabinglucoside, quercetin-3-glucoside, and quercetin-3-rhamnoside, kaempferol-3-rutinoside and kaempferol-3-glucoside. The following compounds were identified in seeds: gallic ...

Tópico(s): Phytochemicals and Antioxidant Activities

2015 - Julius Kühn-Institut | Vitis

Artigo Revisado por pares

Rubén del Barrio‐Galán, Marcela Medel‐Marabolí, Álvaro Peña‐Neira,

The effect of high levels of the polysaccharide Saccharomyces cerevisiae yeast strain (HPS) and another conventional yeast strain (FERM) on the polysaccharide and phenolic composition of Syrah red wines during alcoholic fermentation and subsequent aging on lees, with or without oak wood chips, and on inactive dry yeast was investigated. The HPS yeast released higher amounts of polysaccharides during alcoholic fermentation than FERM yeast (485 g L−1 and 403 g L−1, respectively) and after the aging period ( ...

Tópico(s): Horticultural and Viticultural Research

2015 - Elsevier BV | Food Chemistry

Artigo Acesso aberto Revisado por pares

Claudio Muñoz, Sebastián Gómez‐Talquenca, Constanza Chialva, Javier Ibáñez, José M. Martı́nez-Zapater, Álvaro Peña‐Neira, Diego Lijavetzky,

Anthocyanin profiles are commonly used for grapevine cultivar identification because it is currently accepted that this trait is closely related to their genetic characteristics. Nevertheless, the extent of the variation for the anthocyanin profiles among clones of the same cultivar has not yet been studied in depth. The relative concentration of anthocyanins of 131 Malbec clones grown in the same vineyard was investigated by HPLC-DAD and the use of comprehensive statistic procedures. Complementarily, ...

Tópico(s): Fermentation and Sensory Analysis

2014 - American Chemical Society | Journal of Agricultural and Food Chemistry

Artigo Revisado por pares

Guzmán Favre, Álvaro Peña‐Neira, Cecilia Baldi, Natalia Hernández Sánchez, Sofía Traverso, Graciela Gil, Gustavo González‐Neves,

Low molecular weight phenols of Tannat red wines produced by Traditional Maceration (TM), Prefermentative Cold Maceration (PCM), Maceration Enzyme (ENZ) and grape-Seed Tannins additions (ST), were performed and discussed. Alternatives to TM increased wine phenolic contents but unequally, ST increased mainly smaller flavans-3-ol, PCM anthocyanins and ENZ proanthocyanidins (up to 2250 mg/L). However low molecular weight flavan-3-ols remained below 9 mg/L in all wines, showing that there is not necessarily ...

Tópico(s): Phytochemicals and Antioxidant Activities

2014 - Elsevier BV | Food Chemistry

Artigo Revisado por pares

Aarón de la Cerda‐Carrasco, Remigio López‐Solís, Hugo Nuñez‐Kalasic, Álvaro Peña‐Neira, Elías Obreque‐Slier,

Abstract BACKGROUND Phenolic compounds are widely distributed secondary metabolites in plants usually conferring them with unique taste, flavour and health‐promoting properties. In fruits of Vitis vinifera L., phenolic composition is highly dependent on grape variety. Differential extraction of these compounds from grapes during winemaking is critically associated with wine quality. By‐products of winemaking, such as grape pomace, can contain significant amounts of polyphenols. However, information ...

Tópico(s): Horticultural and Viticultural Research

2014 - Wiley | Journal of the Science of Food and Agriculture

Artigo Revisado por pares

Elías Obreque‐Slier, Álvaro Peña‐Neira, Remigio López‐Solís, Alejandro Cáceres‐Mella, Héctor Toledo, Américo López-Rivera,

Phenolic composition of skins from Vitis vinifera L. cv Carménère (CA), Merlot (M), Cabernet Franc (CF) and Cabernet Sauvignon (CS) grapes during ripening was evaluated by HPLC-DAD and spectrophotometric analysis. At the time of harvest maturity, CS skins showed the highest contents of monomeric, oligomeric and polymeric flavan-3-ols with respect to other varieties. Likewise, the L∗, C∗ and a∗ CIElab parameters showed no statistical differences between the four varieties but the H∗ and b∗ CIElab parameters ...

Tópico(s): Phytochemicals and Antioxidant Activities

2013 - Elsevier BV | LWT