Characterization of dyes extracted from Antarctic red algae for their use in DSSC

En este trabajo se realizó la extracción en medio acuoso de ficoeritrina proveniente de algas rojas de la Isla Rey Jorge. Las especies que mostraron mejores rendimientos de extracción fueron Palmaria decipiens y Delesseria lancifolia. Esta ficoeritrina mostró un comportamiento adecuado para su uso como sensibilizador en celdas de tipo DSSC (dye sensitized solar cells), con altos valores de absorbancia, buena estabilidad con la temperatura y adecuado potencial redox.In this work, the extraction of phycoerythrin of red algae from King George’s Island was performed in aqueous media. Among analyzed, best extraction yields were obtained from Palmaria decipiens and Delesseria lancifolia. This phycoerythrin showed adequate characteristics to be used as sensitizer in DSSC (dye sensitized solar cells).with high absorbance values, good stability towards temperature and a satisfactory redox potential value

Caracterización de pigmentos extraídos de algas rojas de la Antártida para su posible uso en celdas solares del tipo DSSC = Characterization of dyes extracted from Antarctic red algae for their use in DSSC

En este trabajo se realizó la extracción en medio acuoso de ficoeritrina proveniente de algas rojas de la Isla Rey Jorge. Las especies que mostraron mejores rendimientos de extracción fueron Palmaria decipiens y Delesseria lancifolia.Esta ficoeritrina mostró un comportamiento adecuado para su uso como sensibilizador en celdas de tipo DSSC (dye sensitized solar cells), con altos valores de absorbancia, buena estabilidad con la temperatura y adecuado potencial redo

Caracterización de pigmentos extraídos de algas rojas de la Antártida para su posible uso en celdas solares del tipo DSSC

In this work, the extraction of phycoerythrin of red algae from King George’s Island was performed in aqueous media. Among analyzed, best extraction yields were obtained from Palmaria decipiens and Delesseria lancifolia. This phycoerythrin showed adequate characteristics to be used as sensitizer in DSSC (dye sensitized solar cells) with high absorbance values, good stability towards temperature and a satisfactory redox potential value.En este trabajo se realizó la extracción en medio acuoso de ficoeritrina proveniente de algas rojas de la Isla Rey Jorge. Las especies que mostraron mejores rendimientos de extracción fueron Palmaria decipiens y Delesseria lancifolia. Esta ficoeritrina mostró un comportamiento adecuado para su uso como sensibilizador en celdas de tipo DSSC (dye sensitized solar cells), con altos valores de absorbancia, buena estabilidad con la temperatura y adecuado potencial redox

Biomimetic Tendrils by Four Dimensional Printing Bimorph Springs with Torsion and Contraction Properties Based on Bio‐Compatible Graphene/Silk Fibroin and Poly(3-Hydroxybutyrate‐co‐3‐Hydroxyvalerate)

Taking inspiration from plant tendril geometry, in this study, 4D bimorph coiled structures with an internal core of graphene nanoplatelets-modified regenerated silk and an external shell of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) are fabricated by 4D printing. Finite element simulations and experimental tests demonstrate that integrating these biomaterials with different coefficients of thermal expansion results in the temperature induced self-compression and torsion of the structure. The bimorph spring also exhibits reversible contractive actuation after exposure to water environment that paves its exploitation in regenerative medicine, since core materials also have been proven to be biocompatible. Finally, the authors validate their findings with experimental measurements using such springs for temperature-mediated lengthening of an artificial intestine. © 2021 The Authors. Advanced Functional Materials published by Wiley-VCH Gmb

Printable smart 3D architectures of regenerated silk on poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

In this study, we report the fabrication of two different three-dimensional (3D) architectures of regenerated silk (RS) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with embedded functionalities. 3D printed cylinders with an internal layer of PHBV and an external of calcium ions (Ca++) or potassium nitrate (KNO3) modified RS were designed to control the radial shrinkage, water uptake and compression strength. Such cylinders were then used as sutureless thermoresponsive clips, measuring the bursting resistance once applied on an anastomized porcine intestine. Experimental data are supported by finite element simulations that model the tube contraction, demonstrating the possibility to program the shape-changing behavior of 3D printed structures. Printing RS on PHBV, we obtained responsive 3D grids to external force with self-powering properties. The synergic effect obtained by combining materials on appropriate architectures paves the way to potential clinical applications ranging from monitoring of vital signs to sutureless sealant patches

Carbon Nanotubes/Regenerated Silk Composite as a Three-Dimensional Printable Bio-Adhesive Ink with Self-Powering Properties

In this study, regenerated silk (RS) obtained from Bombyx Mori cocoons is compounded with carboxyl-functionalized carbon nanotubes (f-CNTs) in an aqueous environment for the fabrication of functional bio-adhesives. Molecular interactions between RS and carboxyl groups of CNTs result in structural increase of the β-sheet formation, obtaining a resistant adhesive suitable for a wet biological substrate. Moreover, the functionalization of CNTs promotes their dispersion in RS, thus enabling the production of films with controlled electrical conductivity. The practical utility of such a property is demonstrated through the fabrication of a piezoelectric device implanted in a rat to monitor the breathing in vivo and to be used as a self-powered system. Finally, RS/f-CNTs were used as a printable biomaterial ink to three dimensionally print bilayer hollow tubular structures composed of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and RS. Initial tests carried out by seeding and growing human skin fibroblasts demonstrated that the 3D printed bilayer hollow cylindrical structures offer a suitable surface for the seeded cells to attach and proliferate. In general, the herein proposed RS/f-CNT composite serves as a versatile material for solvent-free dispersion processing and 3D printing, thus paving a new approach to prepare multifunctional materials with potential applications of great interest in sealing biological substrates and implantable devices for regenerative medicine

Environmental and societal factors associated with COVID-19-related death in people with rheumatic disease: an observational study

Published by Elsevier Ltd.Background: Differences in the distribution of individual-level clinical risk factors across regions do not fully explain the observed global disparities in COVID-19 outcomes. We aimed to investigate the associations between environmental and societal factors and country-level variations in mortality attributed to COVID-19 among people with rheumatic disease globally. Methods: In this observational study, we derived individual-level data on adults (aged 18-99 years) with rheumatic disease and a confirmed status of their highest COVID-19 severity level from the COVID-19 Global Rheumatology Alliance (GRA) registry, collected between March 12, 2020, and Aug 27, 2021. Environmental and societal factors were obtained from publicly available sources. The primary endpoint was mortality attributed to COVID-19. We used a multivariable logistic regression to evaluate independent associations between environmental and societal factors and death, after controlling for individual-level risk factors. We used a series of nested mixed-effects models to establish whether environmental and societal factors sufficiently explained country-level variations in death. Findings: 14 044 patients from 23 countries were included in the analyses. 10 178 (72·5%) individuals were female and 3866 (27·5%) were male, with a mean age of 54·4 years (SD 15·6). Air pollution (odds ratio 1·10 per 10 μg/m3 [95% CI 1·01-1·17]; p=0·0105), proportion of the population aged 65 years or older (1·19 per 1% increase [1·10-1·30]; p<0·0001), and population mobility (1·03 per 1% increase in number of visits to grocery and pharmacy stores [1·02-1·05]; p<0·0001 and 1·02 per 1% increase in number of visits to workplaces [1·00-1·03]; p=0·032) were independently associated with higher odds of mortality. Number of hospital beds (0·94 per 1-unit increase per 1000 people [0·88-1·00]; p=0·046), human development index (0·65 per 0·1-unit increase [0·44-0·96]; p=0·032), government response stringency (0·83 per 10-unit increase in containment index [0·74-0·93]; p=0·0018), as well as follow-up time (0·78 per month [0·69-0·88]; p<0·0001) were independently associated with lower odds of mortality. These factors sufficiently explained country-level variations in death attributable to COVID-19 (intraclass correlation coefficient 1·2% [0·1-9·5]; p=0·14). Interpretation: Our findings highlight the importance of environmental and societal factors as potential explanations of the observed regional disparities in COVID-19 outcomes among people with rheumatic disease and lay foundation for a new research agenda to address these disparities.MAG is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (grant numbers K01 AR070585 and K24 AR074534 [JY]). KDW is supported by the Department of Veterans Affairs and the Rheumatology Research Foundation Scientist Development award. JAS is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (grant numbers K23 AR069688, R03 AR075886, L30 AR066953, P30 AR070253, and P30 AR072577), the Rheumatology Research Foundation (K Supplement Award and R Bridge Award), the Brigham Research Institute, and the R. Bruce and Joan M. Mickey Research Scholar Fund. NJP is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (T32-AR-007258). AD-G is supported by grants from the Centers for Disease Control and Prevention and the Rheumatology Research Foundation. RH was supported by the Justus-Liebig University Giessen Clinician Scientist Program in Biomedical Research to work on this registry. JY is supported by grants from the National Institutes of Health (K24 AR074534 and P30 AR070155).info:eu-repo/semantics/publishedVersio