639 research outputs found

    Películas a base de proteínas de salvado de arroz enriquecidas por el extracto fenólico de salvado de arroz fermentado y por la arcilla montmorillonítica

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    Proteins extracted from rice bran were used to prepare bio-base films where a factorial experimental design was performed in order to evaluate the effect of protein and glycerol concentrations, and the addition of phenolic extract and montmorillonite (MMT) clay on their physicochemical properties. The phenolic extract was obtained from fermentation of rice bran in solid state with the fungus Rhizopus oryzae. Results showed that protein concentration affected (p < 0.05) the luminosity, opacity and solubility of the films. An increase of glycerol concentration strongly affects (p < 0.05) the values of mechanical properties and water vapor permeability of the films. The addition of phenolic extract to the films affected (p < 0.05) opacity, tensile strength, elongation, Youngs modulus and water vapor permeability, while addition of MMT decreased (p < 0.05) the mechanical properties of the films. Films presented solubility values of less than 25%, luminosity above 80 (L*), opacity above 14%, tensile strength of 8.6 MPa, elongation of 70%, elasticity above 600 MPa and water vapor permeability of 7.5 g.mm/d.m2.kPa. These results show that rice bran protein can be used in the production of bio-based films to further use in food applications.Con el fin de evaluar el efecto que sobre las propiedades fisicoquímicas de las proteínas extraídas del salvado de arroz tienen distintas concentraciones de proteína y de glicerol, así como la adición de extracto fenólico y de arcilla montmorillonítica, las mismas se utilizaron para preparar películas de base biológica en el marco de un diseño experimental factorial. Mediante la fermentación de salvado de arroz en estado sólido con el hongo Rhizopus oryzae, se obtuvo el extracto fenólico. Los resultados demuestran que la concentración proteica afectó significativamente (p < 0,05) la luminosidad, la opacidad y la solubilidad de las películas. Asimismo, un aumento de la concentración de glicerina afectó fuertemente (p < 0,05) los valores de las propiedades mecánicas y de la permeabilidad al vapor de agua de las mismas. La adición de extracto fenólico a las películas afectó de manera significativa (p < 0,05) la opacidad, la fuerza de tensión, el alargamiento, el módulo de Young y la permeabilidad al vapor de agua, mientras que la adición de montmorillonita disminuyó (p < 0,05) sus propiedades mecánicas. Se constató que las películas mostraron valores de solubilidad inferiores a 25%, de luminosidad superiores a 80 (L*), de opacidad superiores a 14%, de fuerza de tensión de 8,6 MPa, de alargamiento de 70%, de elasticidad superiores a 600 MPa y de permeabilidad al vapor de agua de 7,5 g.mm/d.m2 .kPa. Estos resultados demuestran que, en el ámbito de los alimentos, la proteína de salvado de arroz puede utilizarse para la producción de películas de base biológica con el fin de adjudicarle usos adicionales.Authors Cristiano G. Schmidt and Miguel A. Cerqueira are thankful to Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES, Brazil; BEX 9730/11-7) and Fundacao para a Ciencia e Tecnologia, POPH-QREN and FSE (FCT, Portugal) (SFRH/BPD/72753/2010) for financial support. The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the project "BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes", REF.NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON. 2 - O Novo Norte), QREN, FEDER

    Controlled One-Pot Synthesis of Polystyrene-block-Polycaprolactone Copolymers by Simultaneous RAFT and ROP

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    A convenient one-pot method for the controlled synthesis of polystyrene- block -polycaprolactone (PS- b -PCL) copolymers by simultaneous reversible addition?fragmentation chain transfer (RAFT) and ring-opening polymerization (ROP) processes is reported. The strategy involves the use of 2-(benzylsulfanylthiocarbonylsulfanyl)ethanol (1) for the dual roles of chain transfer agent (CTA) in the RAFT polymerization of styrene and co-initiator in the ROP of ε -caprolactone. One-pot poly merizations using the electrochemically stable ROP catalyst diphenyl phosphate (DPP) yield well-defi ned PS- b -PCL in a relatively short reaction time (≈4 h; Mn = 9600−43 600 g mol−1 ; Mw/Mn = 1.21−1.57). Because the hydroxyl group is strategically located on the Z substituent of the CTA, segments of these diblock copolymers are connected through a trithiocarbonate group, thus offering an easy way for subsequent growth of a third segment between PS and PCL. In contrast, an oxidatively unstable Sn(Oct) 2 ROP catalyst reacts with (1) leading to multimodal distributions of polymer chains with variable composition.Fil: de Freitas, Augusto G. O.. Universidade Federal de Santa Maria; BrasilFil: Trindade, Suelen G.. Universidade Federal de Santa Maria; BrasilFil: Muraro, Paulo I. R.. Universidade Federal de Santa Maria; BrasilFil: Schmidt, Vanessa. Universidade Federal de Santa Maria; BrasilFil: Satti, Angel Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Planta Piloto de Ingeniería Química (i); ArgentinaFil: Villar, Marcelo Armando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Planta Piloto de Ingeniería Química (i); ArgentinaFil: Ciolino, Andrés Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Planta Piloto de Ingeniería Química (i); ArgentinaFil: Giacomelli, Cristiano. Universidade Federal de Santa Maria; Brasi

    Neurocognitive Dysfunction in Systemic Lupus Erythematosus: Association with Antiphospholipid Antibodies, Disease Activity and Chronic Damage

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    Introduction: Systemic lupus erythematosus (SLE) is characterized by frequent neuropsychiatric involvement, which includes cognitive impairment (CI). We aimed at assessing CI in a cohort of Italian SLE patients by using a wide range of neurocognitive tests specifically designed to evaluate the fronto-subcortical dysfunction. Furthermore, we aimed at testing whether CI in SLE is associated with serum autoantibodies, disease activity and chronic damage. Methods: Fifty-eight consecutive patients were enrolled. Study protocol included data collection, evaluation of serum level

    Genetic variants in novel pathways influence blood pressure and cardiovascular disease risk.

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    Blood pressure is a heritable trait influenced by several biological pathways and responsive to environmental stimuli. Over one billion people worldwide have hypertension (≥140 mm Hg systolic blood pressure or  ≥90 mm Hg diastolic blood pressure). Even small increments in blood pressure are associated with an increased risk of cardiovascular events. This genome-wide association study of systolic and diastolic blood pressure, which used a multi-stage design in 200,000 individuals of European descent, identified sixteen novel loci: six of these loci contain genes previously known or suspected to regulate blood pressure (GUCY1A3-GUCY1B3, NPR3-C5orf23, ADM, FURIN-FES, GOSR2, GNAS-EDN3); the other ten provide new clues to blood pressure physiology. A genetic risk score based on 29 genome-wide significant variants was associated with hypertension, left ventricular wall thickness, stroke and coronary artery disease, but not kidney disease or kidney function. We also observed associations with blood pressure in East Asian, South Asian and African ancestry individuals. Our findings provide new insights into the genetics and biology of blood pressure, and suggest potential novel therapeutic pathways for cardiovascular disease prevention

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Cold atoms in space: community workshop summary and proposed road-map

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    We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies

    Cold atoms in space: community workshop summary and proposed road-map

    Get PDF
    We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies.publishedVersio
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