1,257 research outputs found

    Compatibilization of recycled polypropylene and recycled poly (ethylene terephthalate) blends with SEBS-g-MA

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    The compatibilization of recycled PP/PET blend with high and low concentration (20 and 5 phr) of elastomer functionalized by maleic anhydride (SEBS-g-MA) was achieved. Recycled polypropylene from plastic industry and recycled PET from post-consumer bottles was used. PP/PET blends: 80:20 w/w, 50:50 w/w and 20:80 w/w were prepared in an internal mixer for mechanical properties, thermal properties, morphology and rheological properties. SEBS-g-MA promoted compatibilization of the PP/PET blends and improved their properties. With an increasing compatibilization level, the refinement of morphology was observed in the PET rich blend. Compatibilized blends showed negative deviation in the PET glass transition temperature related to neat PET, demonstrating that compatibilization was very successful. PET crystallization was accelerated in the blends due to PP presence that enhanced nucleation. It was found that the 50/50/20 blend showed huge potential for textile fiber application and that of 80/20/20 showed more intermediary properties than neat polymers2818491sem informaçãosem informaçã

    The role of technology transfer for the development of a local wind component industry in Chile

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    This paper contributes to the debate about climate change technology transfer by analysing barriers and enablers for a Chilean company starting up the production of wind blades. Literature on the role of technology transfer for the development and deployment of local renewable energy technologies in developing countries often refers to success stories in Brazil, India and China. Instead, this case study highlights the different challenges faced by smaller emerging economies. The paper argues that successful technology transfer in a smaller economy like Chile requires: a minimum internal demand and access to regional markets to attract foreign knowledge providers; a focus in the types of technologies where the recipient country or company have a competitive advantage; and active learning processes by the recipient company. Lessons are drawn for improving the design and implementation of technology-push and market-pull policies in small or medium emerging economies

    Iron-caseinglycomacropeptide complexes: characterization and application in beverages

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    Complexing iron with organic compounds has been considered an alternative strategy to mitigate the problems associated with the level of bioavailable iron and the acceptability of products supplemented with this mineral. CMP contains specific amino acids associated with iron binding. The present study aims to optimize the conditions of Fe/CMP complex formation and understand the molecular basis of interactions between CMP and iron ions. Results showed that CMP can bind ferrous iron in a 1:1.5 M ratio, forming a stable peptide-iron complex, where CMP assembles in a tetrameric form. FTIR spectra indicated that iron binding altered the secondary structures of CMP. The iron-binding sites of CMP corresponded primarily to acid residues of Glu, Asp and sialic acid. Moreover, Fe/CMP complex remained stable in a wide pH range (2.0–6.5), suggesting the adequacy to be efficiently added in food or beverages and to keeping complexed in the digestion environment. Finally, Fe/CMP complex was added to a commercial beverage (2 mg of Fe per serving of beverage) and no changes were observed in their colour during storage. A model to explain the binding between CMP and iron is proposed. These results suggest a potential application of this peptide for iron fortification.Fil: Morales, Rocio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; ArgentinaFil: Martinez, María Julia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; ArgentinaFil: Pilosof, Ana Maria Renata. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; Argentin

    Gestión de recursos humanos y calidad de atención en hospitalización medicina, Hospital II EsSalud Tarapoto – 2022

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    La investigación tuvo como objetivo determinar la relación entre la gestión de recursos humanos y calidad de atención en hospitalización medicina, Hospital II EsSalud Tarapoto – 2022. La investigación fue tipo básica, diseño no experimental, transversal y descriptivo correlacional, con una población de 46 colaboradores y 116 usuarios externos. Con una muestra de 46 colaboradores y 89 usuarios externos. La técnica fue la encuesta y el instrumento cuestionario. Los resultados determinaron que el nivel de gestión de recursos humanos fue regular en 63%, malo en 37 % y bueno en 0 %; la calidad de atención fue regular en 67,4%, malo en 25,8% y bueno en 6,7 %. Concluyendo que existe relación significativa entre la gestión de recursos humanos y calidad de atención en hospitalización medicina, Hospital II EsSalud Tarapoto – 2022, ya que el análisis estadístico de Rho de Spearman fue de r = 0.796 (correlación positiva alta) y un valor de p igual a 0,000 (valor p ≤ 0,05); además, solo el 63.00 % de la gestión de recursos humanos influye en la calidad de atención

    El dinamismo probatorio en la responsabilidad civil médica : análisis de la norma y propuesta de interpretación en aras de evitar vulneraciones al debido proceso

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    Mediante la presente investigación se realizó un estudio de la normatividad procesal vigente frente a los aspectos que pueden resultar problemáticos en la práctica jurídica respecto al tema del dinamismo probatorio en procesos de responsabilidad civil médica, con el objetivo de hacer una propuesta de interpretación de la norma procesal a fin de evitar vulneraciones al debido proceso. Una inversión de la carga de la prueba representa una modificación del supuesto de hecho de la norma sustancial, por lo cual se sugiere que la correcta interpretación de la norma consista en comprender que el dinamismo probatorio parte de los conceptos de disponibilidad y facilidad de la prueba, que representan razones válidas para imponer a la parte que no tiene la carga de probar, el deber de colaboración con el fin de que se cuente con medios probatorios relevantes que ayuden a esclarecer la verdad de los hechos.The present investigation aims to carry out a study of the legal-procedural practice defined as dynamic burden of proof within the framework of medical liability. More precisely, it addresses the study of actual procedural regulations, in the framework of evidence law, that deal with problematic features of the legal practice on this professional field. The primary objective of this work is to offer a proper interpretation of the procedural law that is in line with the core principles of the Colombian law order and, specially, that avoids due process violations. The reversal of the burden of proof –which has been widely discussed and applied by the legal practitioners– implies a modification of the factual basis of the substantive norm and, therefore, has important implications that can lead to the infringement of the basic tenets of the procedural law. It is for this reason that the definition of a set of criteria for the correct interpretation of current legislation appears to be an urgent task. Considering that the dynamic burden of proof is built on the concepts of proof availability and proof proximity –which are valid reasons for the reversal of the burden of proof–, the duty of cooperation which must inform the recollection of evidence should be clear and well-defined in order to be useful in ascertaining the procedural truth

    Etnobotânica de espécies arbóreas e arbustivas no Parque Natural de Montesinho

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    Carvalho, Ana Maria; Fernandes, Mariana; Pardo de Santayana, Manuel; Morales, Ramón (2005) – Etnobotânica de espécies arbóreas e arbustivas no Parque Natural de Montesinho. In V Congresso Florestal Nacional. Vise

    Importancia de los modelos de conducta en la intención emprendedora en estudiantes de ingeniería = The importance of role models for the entrepreneurial intention of technical degrees students

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    El emprendimiento de base tecnológica es un tema crítico para la generación de crecimiento económico, por lo que conocer los determinantes de la intención emprendedora de estudiantes de universidades técnicas adquiere una especial relevancia. En este estudio se analiza la importancia de los modelos de conducta en la intención emprendedora entre los estudiantes de carreras técnicas. Los resultados muestran que los estudiantes de padres empresarios tienen una intención emprendedora superior a la media, mientras que los de hijos de padres funcionarios están por debajo de ella. Igualmente, la ausencia de modelos de conducta emprendedora en el entorno cercano disminuye la intención emprendedora, mientras que la ausencia de funcionarios no la hace aumentar

    Characterizing the hydrogeochemistry of two low-temperature thermal systems in Central Mexico

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    Two low-temperature geothermal systems located at the Trans-Mexican Volcanic Belt with presence of fluoride and arsenic were studied with the aim to determine hydrogeochemical indicators of the toxic elements' presence, and to propose adequate geothermometers. The hydrogeological and geochemical study was carried out in Ixtapan de la Sal and Tonatico (IxS-T) and Santa Cruz de Juventino Rosas (JR), both located at the limits of the Trans-Mexican Volcanic Belt (TMVB). In these regions, low-temperature geothermal activity is present (T = 32–47 °C), and various fault and fracture systems have been identified. Several faults are active, enabling the upward flow of deep geothermal water. The geothermal waters of IxS-T manifest in the form of springs and have high Na+ and Cl− concentrations, whereas those of JR are captured in wells and mainly present high Na+ and HCO3 – concentrations. The hydrochemistry of water samples was analyzed to determine the dominant hydrogeochemical processes in both regions. These data were also useful for understanding the natural origin of the high levels of arsenic and fluoride reported in the water, which are likely due to mineral dissolution processes. The concentrations of these elements surpassed the permissible limits according to Mexican law (Astot = 0.025 mg/L; F− = 1.5 mg/L) and represent a toxicity risk for the local populations. The groundwater at JR supplies all needs of the local population, while the water at IxS-T is mainly used for recreational and health spa purposes. Increasing trends of As and F− in the sedimentary aquifer of IxS-T are related with the increase in TDS, Cl−, HCO3 – and SiO2, while silicate alteration releasing Na and HCO3 – are related with As and F− presence in the volcanic aquifer of JR. Reservoir temperature was adequately estimated with K2 /Mg and Na-K-Ca (Mg corrected) geothermometers at IxS-T, and with chalcedony and quartz geothermometers at JRUAEM 3716/201

    Unraveling the relationship between conditions of ultrasonic-assisted extraction of chia mucilage and viscosity

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    BACKGROUND: The application of chia mucilage still remains restricted due to the difficulty in achieving high extraction yields. The effect of ultrasonic-assisted extraction (UAE) conditions (temperature, seed:water ratio and time) on the rheological properties of chia mucilage extracts and the relation to the proportion of translucent phase (TP) and opaque phase (OP) of the mucilage in the extract were evaluated. RESULTS: UAE allowed the efficient extraction of chia mucilage from chia seeds. The desired overall optimal combination to maximize both yield and apparent viscosity was achieved at a seed:water ratio 1:10, a temperature of 25.3 °C and 53.7 min extraction time; the optimal conditions to obtain the maximum yield and minimum apparent viscosity were a seed:water ratio close to 1:20, temperature of 48.8 °C and 208.4 min extraction time. CONCLUSION: The results obtained in the present work demonstrated that the differences in rheological properties of chia mucilage extracts are due to the extraction methods used. Therefore, it is possible to modulate the extraction conditions in order to obtain different characteristics of the mucilage, maintaining a high extraction yield.Fil: Saporittis, Karen. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; ArgentinaFil: Marasco, Julieta. Universidad de Buenos Aires. Facultad de Ingeniería; ArgentinaFil: Morales, Rocio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; ArgentinaFil: Martinez, María Julia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; ArgentinaFil: Pilosof, Ana Maria Renata. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; Argentin

    Recapitulation of Hypoxic Tumor–stroma Microenvironment to Study Photodynamic Therapy Implications

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    Tumor microenvironment (TME) is a dynamic ecosystem where fibroblasts are recruited in order to provide a niche to support growth and, in some extent, to promote therapeutic resistance. However, the role of fibroblasts in stimulating or impairing photodynamic therapy (PDT) outcome has not yet been fully addressed. PDT is based on interactions between light, oxygen and photosensitizer, leading to phototoxic reactions that culminate in cell death. In this study, we demonstrated the consequences of a hypoxic stromal phenotype on tumor mass for exploring PDT response. We mimicked TME complexity implementing colon cancer cells and fibroblasts 3D cultures called spheroids. Using hypoxia reporting lines, we verified that homotypic spheroids exhibited a size-dependent transcriptional HIF-1 activity. When cocultured, fibroblasts were localized in the hypoxic core. In homotypic stromal spheroids, the distribution of the endogenous photosensitizer PpIX was homogeneous while decreased in hypoxic areas of tumor 3D cultures. When monocultured, fibroblasts were more efficient to produce PpIX from its prodrug Me-ALA. Interestingly, the cross talk between cancer cells and fibroblasts attenuated PpIX accumulation and conferred tumor PDT resistance when compared to homotypic 3D cultures. Overall, our data suggest that stroma and tumor act in an integrated, reciprocal fashion which could ultimately influence on therapeutic response.Fil: Lamberti, María Julia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Morales Vasconsuelo, Ana Belen. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Ferrara, Maria Gracia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Rumie Vittar, Natalia Belen. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentin
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