98 research outputs found
¿Se pueden conseguir plásticos barrera a medida?
La Industria del Envase y Embalaje forma parte de uno de los sectores principales de aplicación de los materiales polímeros. De todos es conocido que el vidrio, papel y metales que durante muchos años se utilizaron en el embalaje y empaquetamiento de alimentos, bebidas y otros productos han sido parcialmente reemplazados en la actualidad, por sustancias de naturaleza polimérica que permiten la regularización del transporte de gases y vapores a su través.
Se puede decir que uno de los principales problemas con los que se encuentran los profesionales del Sector es encontrar la mejor protección de los productos desde su empaquetamiento hasta su utilización final por el consumidor. La preservación de la calidad de los productos envasados involucra no solo la protección del sabor sino también la necesidad de evitar malos olores en el alimento envasado. De ahí la importancia que el análisis de las propiedades de transporte de masas en los filmes tiene en la industria del envasado.
Sin embargo los estudios del transporte de gases y/o vapores son complejos ya que la permeabilidad del material es el resultado de diferentes etapas, por un lado la solubilidad del gas en una cara de la membrana y por otro su difusión en el interior del film hacia la otra cara y su desorción de la misma. Todas estas etapas están fuertemente influenciadas por una serie de factores, como la naturaleza del film polimérico, la temperatura de uso, los aditivos (cargas o plastificantes), etc…, que hay que tener en cuenta a la hora de diseñar un material apto para envasado.
Por tanto, el objetivo de esta conferencia es revisar los factores que hay que considerar en el transporte de gases a través de membranas poliméricas densas, desde un punto de vista químico-físico, mostrando diversos ejemplos de cómo se pueden modificar estas propiedades barrera para adecuarlas a las necesidades del producto a envasar.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
Daily consumption of a dairy drink enriched with DHA, Vitamins and minerals enhanced nutritional status and cognitive abilities parameters
Preadolescence is a period of growth with special nutritional requirements. In this research we
investigated the effects produced by a 5-month consumption of an enriched dairy drink on biochemical and
cognitive development parameters in children.
Methods: 119 children (8 14y) of both genders (male 49%, female 51%) were randomly distributed into two study groups. The supplemented group (SG, n = 60) consumed 0.6 L/day (breakfast, elevenses and teatime) of an enriched dairy drink containing fish oils (high in DHA), oleic acid, carbohydrates (sugar and honey), vitamins (A, B complex, C, D, and E) and minerals (calcium, phosphorus, zinc) (Puleva Max®). The control group (CG, n = 59) consumed 0.6 L/day of standard whole milk. Both groups received the same dietary advice and consumed the dairy drinks for 5-moths, in addition to their usual diet. Blood samples and psychometric tests (some subscales of W.I.S.C.-IV of Wechsler and EVALUA of Vidal) were taken at 0 and 5 months. RM ANOVA was applied. Data are expressed as mean±SEM.
Results: The consumption of the enriched dairy drink (SG) produced significant (p < 0.05) increases in plasma DHA (20%) and calcium (1.5%). Total proteins (1.9%), transferrine (2.1%), total cholesterol (3.3%) and HDLcholesterol (5.2%), but not LDL-cholesterol, decreased significantly in CG. Regarding psychometric parameters, digits span (working memory test), speed reading and reading comprehension scores showed significant increases in SG at the end of the study (16.8%, 19.1%, and 19.0% respectively) whereas CG only showed higher scores in the reading comprehension test (19.2%).
Conclusion: The dietary supplementation with the enriched dairy drink improved the nutritional and biochemical status and a number of cognitive performance markers in children of 8 and 14 years. Supported by Puleva Food SA.Universidad e Granada
Puleva Biotech S
Phase Transformation Dynamics in Sulfate-Loaded Lanthanide Triphosphonates. Proton Conductivity and Application as Fillers in PEMFCs
Phase transformation dynamics and proton conduction properties are reported for cationic layer-featured coordination polymers derived from the combination of lanthanide ions (Ln3+) with nitrilo-tris(methylenephosphonic acid) (H6NMP) in the presence of sulfate ions. Two families of materials are isolated and structurally characterized, i.e., [Ln2(H4NMP)2(H2O)4](HSO4)2·nH2O (Ln = Pr, Nd, Sm, Eu, Gd, Tb, Er, Yb; n = 4−5, Series I) and [Ln(H5NMP)]SO4· 2H2O (Ln = Pr, Nd, Eu, Gd, Tb; Series II). Eu/Tb bimetallic solid solutions are also prepared for photoluminescence studies. Members of families I and II display high proton conductivity (10−3 and 10−2 S·cm−1 at 80 °C and 95% relative humidity) and are studied as fillers for Nafion-based composite membranes in PEMFCs, under operating conditions. Composite membranes exhibit higher power and current densities than the pristine Nafion membrane working in the range of 70−90 °C and 100% relative humidity and with similar proton conductivity.Proyectos de Ministero de Ciencia e Innovación MAT2016-77648-R (MICINN/FEDER); PID2019-110249RB-I00 (MICINN/FEDER) y la Junta de Andalucía (FQM113). Funding for open access change: Universidad de Málaga/ CBU
Contribution of the Microbial Communities Detected on an Oil Painting on Canvas to Its Biodeterioration
In this study, we investigated the microbial community (bacteria and fungi) colonising an oil painting on canvas, which showed visible signs of biodeterioration. A combined strategy, comprising culture-dependent and -independent techniques, was selected. The results derived from the two techniques were disparate. Most of the isolated bacterial strains belonged to related species of the phylum Firmicutes, as Bacillus sp. and Paenisporosarcina sp., whereas the majority of the non-cultivable members of the bacterial community were shown to be related to species of the phylum Proteobacteria, as Stenotrophomonas sp. Fungal communities also showed discrepancies: the isolated fungal strains belonged to different genera of the order Eurotiales, as Penicillium and Eurotium, and the non-cultivable belonged to species of the order Pleosporales and Saccharomycetales. The cultivable microorganisms, which exhibited enzymatic activities related to the deterioration processes, were selected to evaluate their biodeteriorative potential on canvas paintings; namely Arthrobacter sp. as the representative bacterium and Penicillium sp. as the representative fungus. With this aim, a sample taken from the painting studied in this work was examined to determine the stratigraphic sequence of its cross-section. From this information, “mock paintings,” simulating the structure of the original painting, were prepared, inoculated with the selected bacterial and fungal strains, and subsequently examined by micro-Fourier Transform Infrared spectroscopy, in order to determine their potential susceptibility to microbial degradation. The FTIR-spectra revealed that neither Arthrobacter sp. nor Penicillium sp. alone, were able to induce chemical changes on the various materials used to prepare “mock paintings.” Only when inoculated together, could a synergistic effect on the FTIR-spectra be observed, in the form of a variation in band position on the spectrum.The FTIR analyses performed in this study were financed by the Junta de Andalucía (RNM-325 group). The molecular analyses performed in this study were financed by the Austrian Science Fund (FWF) project ‘Hertha-Firnberg T137’ and the Spanish Ministry of Science and Innovation (Project CTQ2008-06727-C03-03). G. Piñar also thanks the “Elise-Richter V194-B20” projects
Influence of the Water Content on the Diffusion Coefficients of Li⁺ and Water across Naphthalenic Based Copolyimide Cation-Exchange Membranes
The transport of lithium ions in cation-exchange membranes based on sulfonated copolyimide membranes is reported. Diffusion coefficients of lithium are estimated as a function of the water content in membranes by using pulsed field gradient (PFG) NMR and electrical conductivity techniques. It is found that the lithium transport slightly decreases with the diminution of water for membranes with water content lying in the range 14 < λ < 26.5, where λ is the number of molecules of water per fixed sulfonate group. For λ < 14, the value of the diffusion coefficient of lithium experiences a sharp decay with the reduction of water in the membranes. The dependence of the diffusion of lithium on the humidity of the membranes calculated from conductivity data using Nernst–Planck type equations follows a trend similar to that observed by NMR. The possible explanation of the fact that the Haven ratio is higher than the unit is discussed. The diffusion of water estimated by 1H PFG-NMR in membranes neutralized with lithium decreases as λ decreases, but the drop is sharper in the region where the decrease of the diffusion of protons of water also undergoes considerable reduction. The diffusion of lithium ions computed by full molecular dynamics is similar to that estimated by NMR. However, for membranes with medium and low concentration of water, steady state conditions are not reached in the computations and the diffusion coefficients obtained by MD simulation techniques are overestimated. The curves depicting the variation of the diffusion coefficient of water estimated by NMR and full dynamics follow parallel trends, though the values of the diffusion coefficient in the latter case are somewhat higher. The WAXS diffractograms of fully hydrated membranes exhibit the ionomer peak at q = 2.8 nm⁻1, the peak being shifted to higher q as the water content of the membranes decreases. The diffractograms present additional peaks at higher q, common to wet and dry membranes, but the peaks are better resolved in the wet membranes. The ionomer peak is not detected in the diffractograms of dry membranes.The authors acknowledge financial support provided by the DGICYT (Dirección General de Investigación Cientifíca y Tecnológica) through Grant MAT2011-29174-C02-02
HTLV-1 infection in solid organ transplant donors and recipients in Spain
HTLV-1 infection is a neglected disease, despite infecting 10-15 million people worldwide and severe illnesses develop in 10% of carriers lifelong. Acknowledging a greater risk for developing HTLV-1 associated illnesses due to immunosuppression, screening is being widely considered in the transplantation setting. Herein, we report the experience with universal HTLV testing of donors and recipients of solid organ transplants in a survey conducted in Spain. All hospitals belonging to the Spanish HTLV network were invited to participate in the study. Briefly, HTLV antibody screening was performed retrospectively in all specimens collected from solid organ donors and recipients attended since the year 2008. A total of 5751 individuals were tested for HTLV antibodies at 8 sites. Donors represented 2312 (42.2%), of whom 17 (0.3%) were living kidney donors. The remaining 3439 (59.8%) were recipients. Spaniards represented nearly 80%. Overall, 9 individuals (0.16%) were initially reactive for HTLV antibodies. Six were donors and 3 were recipients. Using confirmatory tests, HTLV-1 could be confirmed in only two donors, one Spaniard and another from Colombia. Both kidneys of the Spaniard were inadvertently transplanted. Subacute myelopathy developed within 1 year in one recipient. The second recipient seroconverted for HTLV-1 but the kidney had to be removed soon due to rejection. Immunosuppression was stopped and 3 years later the patient remains in dialysis but otherwise asymptomatic. The rate of HTLV-1 is low but not negligible in donors/recipients of solid organ transplants in Spain. Universal HTLV screening should be recommended in all donor and recipients of solid organ transplantation in Spain. Evidence is overwhelming for very high virus transmission and increased risk along with the rapid development of subacute myelopathy
Código de conduta. Prevenção da introdução e dispersão de flora e fauna exótica invasora: agentes ambientais
De forma intencional ou involuntária, o ser humano transporta espécies entre locais desde tempos imemoriais. No entanto, nos últimos 50 anos, o ritmo de introdução de espécies exóticas no meio natural acelerou de forma alarmante, tornando-se numa das principais causas de perda de biodiversidade. A globalização, juntamente com as alterações climáticas, a destruição de habitats, o aumento do trânsito de pessoas e o comércio, são hoje os principais responsáveis pela perda de biodiversidade a nível global, acarretando também graves prejuízos para a economia e a saúde humana
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
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