2,583 research outputs found
High resolution imaging of NGC 2346 with GSAOI/GeMS: disentangling the planetary nebula molecular structure to understand its origin and evolution
We present high spatial resolution ( 60--90 milliarcseconds) images
of the molecular hydrogen emission in the Planetary Nebula (PN) NGC 2346. The
data were acquired during the System Verification of the Gemini Multi-Conjugate
Adaptive Optics System + Gemini South Adaptive Optics Imager. At the distance
of NGC 2346, 700 pc, the physical resolution corresponds to 56 AU,
which is slightly higher than that an [N II] image of NGC 2346 obtained with
HST/WFPC2. With this unprecedented resolution we were able to study in detail
the structure of the H gas within the nebula for the first time. We found
it to be composed of knots and filaments, which at lower resolution had
appeared to be a uniform torus of material. We explain how the formation of the
clumps and filaments in this PN is consistent with a mechanism in which a
central hot bubble of nebular gas surrounding the central star has been
depressurized, and the thermal pressure of the photoionized region drives the
fragmentation of the swept-up shell.Comment: accepted in ApJ (17 pages, 7 figures, 1 Table
Effect of active phenolic acids on properties of PLA-PHBV blend films
[EN] Phenolic acids (ferulic, p-coumaric, and protocatechuic) have been incorporated into polylactic (PLA): Poly(3hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) (75:25) blend films that were obtained by melt-blending and compression moulding, using PEG1000 as a plasticizer. Film microstructure, thermal behavior, functional properties, and release kinetics of phenolic acids in different food simulants were analyzed, and the film antimicrobial activity against Listeria innocua. Phenolic acids led to an increase in the glass transition temperature of PLA while PHBV supercooling occurred in the films containing protocatechuic acid, which affected their thermal degradation behavior. Polymer matrices with phenolic acids were stiffer and more resistant to break than the polyester blend, but with similar extensibility, while oxygen and water vapor barrier capacity were also improved, especially in films containing protocatechuic acid. The release rate and ratio of phenolic acids increased when the polarity of the food simulant decreased, although very slow delivery was observed in all cases. The limited release of active compounds in aqueous media provoked that films did not significantly inhibit the growth of Listeria innocua in inoculated culture medium.Acknowledgements The authors would like to thank the Ministerio de Ciencia e Innovación of Spain, for funding this study through the Project AGL2016-76699-R and PID2019-105207RB-I00, and the predoctoral research grant #BES-2017-082040.Hernandez-Garcia, E.; Vargas, M.; Chiralt, A. (2022). Effect of active phenolic acids on properties of PLA-PHBV blend films. Food Packaging and Shelf Life. 33:1-11. https://doi.org/10.1016/j.fpsl.2022.1008941113
Quality and Shelf-Life Stability of Pork Meat Fillets Packaged in Multilayer Polylactide Films
[EN] In the present study, the effectiveness of a multilayer film of polylactide (PLA), fully bio-based and compostable, was ascertained to develop a novel sustainable packaging solution for the preservation of fresh pork meat. To this end, the multilayer PLA films were first characterized in terms of their thermal characteristics, structure, mechanical performance, permeance to water and aroma vapors and oxygen, and optical properties and, for the first time, compared with two commercial high-barrier multilayer packaging films. Thereafter, the multilayers were thermosealed to package fillets of fresh pork meat and the physicochemical changes, lipid oxidation levels, and microbiological counts were monitored in the food samples during storage under refrigeration conditions. Results showed that the meat fillets packaged in PLA developed a redder color and showed certain indications of dehydration and oxidation, being more noticeably after 11 days of storage, due to the higher water vapor and oxygen permeance values of the biopolymer multilayer. However, the pH changes and bacterial growth in the cold-stored fresh pork meat samples were minimal and very similar in the three tested multilayer films, successfully accomplishing the requirements of the food quality and safety standards at the end of storage.This research was funded by the Spanish Ministry of Science and Innovation (MICI), grant number PID2019-105207RB-I00.
E.H.-G. and S.T.-G. acknowledge MICI for her predoctoral research grant (BES2017-082040) and his Ramón y Cajal contract (RYC2019-027784-I). The authors are also grateful to
the Packaging Technologies Department of AINIA for the technical support provided during the
determination of the multilayer structures. Derprosa is also acknowledged for gently providing
the multilayer PLA film.Hernandez-Garcia, E.; Vargas, M.; Torres-Giner, S. (2022). Quality and Shelf-Life Stability of Pork Meat Fillets Packaged in Multilayer Polylactide Films. Foods. 11(3):1-20. https://doi.org/10.3390/foods1103042612011
Thermoprocessed starch-polyester bilayer films as affected by the addition of gellar or xantham gum
[EN] Monolayer films based on cassava starch (CS) or maize starch (MS), with and without 10% of gellan or xanthan gum, and PLA-PHBV (75:25) blend films, were obtained by melt-blending and compression moulding, using glycerol (for starch blends) and PEG 1000 (for polyester blends) as plasticisers. Bilayer films were obtained by thermo-compression of the different starch based sheets with the polyester sheet. Both mono and bilayers were characterised as to their mechanical and barrier properties, equilibrium moisture, water solubility and microstructure. The incorporation of gellan gum and xanthan gum improved the mechanical properties of starch-based films, especially in the case of MS, although the highest EM and TS values were obtained for CS-gum films. The incorporation of either gellan or xanthan gum decreased the water vapour and oxygen permeability of starch-based films; the CS films with gums being the least permeable to oxygen. The lowest changes in mechanical properties throughout storage were obtained in cassava starch-based films, especially those containing xanthan gum. Starch based-polyester bilayers presented a high oxygen and water vapour barrier capacity, as compared to their individual monolayers. Bilayer films with cassava starch including the gums showed the lowest OP and WVP values and the highest elastic modulus and tensile strength, with extensibility values in the range of the corresponding monolayers and slight changes in their physical properties throughout time. The bilayer formed with cassava starch with gellan gum and a PLA-PHBV appeared as the best option for food packaging purposes taking into account its functional properties and the good layer adhesion of the bilayer.The authors would like to thank the Ministerio de Ciencia e Innovacion of Spain, for funding this study through the Project AGL2016-76699-R and PID2019-105207RB-I00, and the predoctoral research grant #BES-2017-082040.Hernandez-Garcia, E.; Vargas, M.; Chiralt Boix, MA. (2021). Thermoprocessed starch-polyester bilayer films as affected by the addition of gellar or xantham gum. Food Hydrocolloids. 113:1-9. https://doi.org/10.1016/j.foodhyd.2020.106509S19113Arismendi, C., Chillo, S., Conte, A., Del Nobile, M. A., Flores, S., & Gerschenson, L. N. (2013). Optimization of physical properties of xanthan gum/tapioca starch edible matrices containing potassium sorbate and evaluation of its antimicrobial effectiveness. LWT - Food Science and Technology, 53(1), 290-296. doi:10.1016/j.lwt.2013.01.022Armentano, I., Fortunati, E., Burgos, N., Dominici, F., Luzi, F., Fiori, S., … Kenny, J. M. (2015). Bio-based PLA_PHB plasticized blend films: Processing and structural characterization. LWT - Food Science and Technology, 64(2), 980-988. doi:10.1016/j.lwt.2015.06.032Balaguer, M. P., Gómez-Estaca, J., Gavara, R., & Hernandez-Munoz, P. (2011). Biochemical Properties of Bioplastics Made from Wheat Gliadins Cross-Linked with Cinnamaldehyde. Journal of Agricultural and Food Chemistry, 59(24), 13212-13220. doi:10.1021/jf203055sBonilla, J., Fortunati, E., Vargas, M., Chiralt, A., & Kenny, J. M. (2013). Effects of chitosan on the physicochemical and antimicrobial properties of PLA films. Journal of Food Engineering, 119(2), 236-243. doi:10.1016/j.jfoodeng.2013.05.026Cano, A., Chafer, M., Chiralt, A., & Gonzalez-Martinez, C. (2017). Strategies to Improve the Functionality of Starch-Based Films. Handbook of Composites from Renewable Materials, 311-337. doi:10.1002/9781119441632.ch74Cano, A., Jiménez, A., Cháfer, M., Gónzalez, C., & Chiralt, A. (2014). Effect of amylose:amylopectin ratio and rice bran addition on starch films properties. Carbohydrate Polymers, 111, 543-555. doi:10.1016/j.carbpol.2014.04.075Chaiwutthinan, P., Pimpan, V., Chuayjuljit, S., & Leejarkpai, T. (2014). Biodegradable Plastics Prepared from Poly(lactic acid), Poly(butylene succinate) and Microcrystalline Cellulose Extracted from Waste-Cotton Fabric with a Chain Extender. Journal of Polymers and the Environment, 23(1), 114-125. doi:10.1007/s10924-014-0689-0Gasmi, S., Hassan, M. K., & Luyt, A. S. (2019). Crystallization and dielectric behaviour of PLA and PHBV in PLA/PHBV blends and PLA/PHBV/TiO2 nanocomposites. Express Polymer Letters, 13(2), 199-212. doi:10.3144/expresspolymlett.2019.16McHUGH, T. H., AVENA-BUSTILLOS, R., & KROCHTA, J. M. (1993). Hydrophilic Edible Films: Modified Procedure for Water Vapor Permeability and Explanation of Thickness Effects. Journal of Food Science, 58(4), 899-903. doi:10.1111/j.1365-2621.1993.tb09387.xKim, S. R. B., Choi, Y.-G., Kim, J.-Y., & Lim, S.-T. (2015). Improvement of water solubility and humidity stability of tapioca starch film by incorporating various gums. LWT - Food Science and Technology, 64(1), 475-482. doi:10.1016/j.lwt.2015.05.009Laycock, B., Halley, P., Pratt, S., Werker, A., & Lant, P. (2013). The chemomechanical properties of microbial polyhydroxyalkanoates. Progress in Polymer Science, 38(3-4), 536-583. doi:10.1016/j.progpolymsci.2012.06.003Liu, Q., Wu, C., Zhang, H., & Deng, B. (2015). Blends of polylactide and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with low content of hydroxyvalerate unit: Morphology, structure, and property. Journal of Applied Polymer Science, 132(42), n/a-n/a. doi:10.1002/app.42689López, O. V., Zaritzky, N. E., Grossmann, M. V. E., & García, M. A. (2013). Acetylated and native corn starch blend films produced by blown extrusion. Journal of Food Engineering, 116(2), 286-297. doi:10.1016/j.jfoodeng.2012.12.032Martin, O., Schwach, E., Averous, L., & Couturier, Y. (2001). Properties of Biodegradable Multilayer Films Based on Plasticized Wheat Starch. Starch - Stärke, 53(8), 372. doi:10.1002/1521-379x(200108)53:83.0.co;2-fMuller, J., González-Martínez, C., & Chiralt, A. (2017). Poly(lactic) acid (PLA) and starch bilayer films, containing cinnamaldehyde, obtained by compression moulding. European Polymer Journal, 95, 56-70. doi:10.1016/j.eurpolymj.2017.07.019Ortega-Toro, R., Jiménez, A., Talens, P., & Chiralt, A. (2014). Properties of starch–hydroxypropyl methylcellulose based films obtained by compression molding. Carbohydrate Polymers, 109, 155-165. doi:10.1016/j.carbpol.2014.03.059Ortega-Toro, R., Morey, I., Talens, P., & Chiralt, A. (2015). Active bilayer films of thermoplastic starch and polycaprolactone obtained by compression molding. Carbohydrate Polymers, 127, 282-290. doi:10.1016/j.carbpol.2015.03.080Rasal, R. M., Janorkar, A. V., & Hirt, D. E. (2010). Poly(lactic acid) modifications. Progress in Polymer Science, 35(3), 338-356. doi:10.1016/j.progpolymsci.2009.12.003Requena, R., Vargas, M., & Chiralt, A. (2018). Obtaining antimicrobial bilayer starch and polyester-blend films with carvacrol. Food Hydrocolloids, 83, 118-133. doi:10.1016/j.foodhyd.2018.04.045Sapper, M., Talens, P., & Chiralt, A. (2019). Improving Functional Properties of Cassava Starch-Based Films by Incorporating Xanthan, Gellan, or Pullulan Gums. International Journal of Polymer Science, 2019, 1-8. doi:10.1155/2019/5367164Savadekar, N. R., & Mhaske, S. T. (2012). Synthesis of nano cellulose fibers and effect on thermoplastics starch based films. Carbohydrate Polymers, 89(1), 146-151. doi:10.1016/j.carbpol.2012.02.063Sikora, M., Kowalski, S., & Tomasik, P. (2008). Binary hydrocolloids from starches and xanthan gum. Food Hydrocolloids, 22(5), 943-952. doi:10.1016/j.foodhyd.2007.05.007Silva-Guzmán, J. A., Anda, R. R., Fuentes-Talavera, F. J., Manríquez-González, R., & Lomelí-Ramírez, M. G. (2018). Properties of Thermoplastic Corn Starch Based Green Composites Reinforced with Barley (Hordeum vulgare L.) Straw Particles Obtained by Thermal Compression. Fibers and Polymers, 19(9), 1970-1979. doi:10.1007/s12221-018-8023-4Tampau, A., González-Martínez, C., & Chiralt, A. (2018). Release kinetics and antimicrobial properties of carvacrol encapsulated in electrospun poly-(ε-caprolactone) nanofibres. Application in starch multilayer films. Food Hydrocolloids, 79, 158-169. doi:10.1016/j.foodhyd.2017.12.021Thongpina, C., Tippuwanan, C., Buaksuntear, K., & Chuawittayawuta, T. (2017). Mechanical and Thermal Properties of PLA Melt Blended with High Molecular Weight PEG Modified with Peroxide and Organo-Clay. Key Engineering Materials, 751, 337-343. doi:10.4028/www.scientific.net/kem.751.337Vieira, M. G. A., da Silva, M. A., dos Santos, L. O., & Beppu, M. M. (2011). Natural-based plasticizers and biopolymer films: A review. European Polymer Journal, 47(3), 254-263. doi:10.1016/j.eurpolymj.2010.12.011Ortega-Toro, R., Collazo-Bigliardi, S., Talens, P., & Chiralt, A. (2015). Influence of citric acid on the properties and stability of starch-polycaprolactone based films. Journal of Applied Polymer Science, 133(2), n/a-n/a. doi:10.1002/app.4222
Design, Implementation and Maintenance of a Model Organism Database for Arabidopsis thaliana
The Arabidopsis Information Resource (TAIR) is a web-based community database
for the model plant Arabidopsis thaliana. It provides an integrated view of genes,
sequences, proteins, germplasms, clones, metabolic pathways, gene expression, ecotypes,
polymorphisms, publications, maps and community information. TAIR is developed
and maintained by collaboration between software developers and biologists.
Biologists provide specification and use cases for the system, acquire, analyse and
curate data, interact with users and test the software. Software developers design,
implement and test the database and software. In this review, we briefly describe how
TAIR was built and is being maintained
Healthcare Built Environment and Telemedicine Practice for Social and Environmental Sustainability
The practice of telemedicine started at the beginning of the 20th century but has never
been widely implemented, even though it is significantly sustainable compared to traveling to
healthcare However, the ongoing COVID-19 pandemic pushed organisations and patients to accept
this technology. During the pandemic, telemedicine consultations took place in ad hoc environments
without much preparation and planning. As a result, there is a knowledge gap in the field between
telemedicine’s clinical care services and healthcare built environment, in terms of design. This research
focused on addressing the quality of service and experience of telemedicine in primary healthcare
settings and how this could be influenced by the digital infrastructure. Our aim was to understand
the correlations between telemedicine and healthcare built environment and whether the latter could
have a significant impact on telemedicine practice. The methodology included interviews with
professionals involved in healthcare planning, architecture and ethnography, and end user research
involving telemedicine sessions. The interviews highlighted that professionals involved in the design
of healthcare environments demonstrated limited consideration of telemedicine environments. Yet,
the ethnographic, end-user research identified areas where the telemedicine environment could affect
user experience and should be taken into consideration in the design of such spaces
Biodegradation of PLA-PHBV Blend Films as Affected by the Incorporation of Different Phenolic Acids
[EN] Films based on a 75:25 polylactic acid (PLA) and Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) blend, containing 2% (w/w) of different phenolic acids (ferulic, p-coumaric or protocatechuic acid), and plasticised with 15 wt. % polyethylene glycol (PEG 1000), were obtained by melt blending and compression moulding. The disintegration and biodegradation of the film under thermophilic composting conditions was studied throughout 35 and 45 days, respectively, in order to analyse the effect of the incorporation of the antimicrobial phenolic acids into the films. Sample mass loss, thermo-degradation behaviour and visual appearance were analysed at different times of the composting period. No effect of phenolic acids was observed on the film disintegration pattern, and the films were completely disintegrated at the end of the composting period. The biodegradation analysis through the CO2 measurements revealed that PLA-PHBV blend films without phenolic acids, and with ferulic acid, completely biodegraded after 20 composting days, while p-coumaric and protocatechuic slightly retarded full biodegradation (21 and 26 days, respectively). Phenolic acids mainly extended the induction period, especially protocatechuic acid. PLA-PHBV blend films with potential antimicrobial activity could be used to preserve fresh foodstuff susceptible to microbial spoilage, with their biodegradation under composting conditions being ensured.FundingThis research was funded by Ministerio de Ciencia e Innovacion of Spain through the Project AGL2016-76699-R, PID2019-105207RB-I00, and the predoctoral research grant #BES-2017-082040.Hernandez-Garcia, E.; Vargas, M.; Chiralt Boix, MA.; González Martínez, MC. (2022). Biodegradation of PLA-PHBV Blend Films as Affected by the Incorporation of Different Phenolic Acids. Foods. 11(2):1-15. https://doi.org/10.3390/foods1102024311511
Biodegradable Antimicrobial Films for Food Packaging: Effect of Antimicrobials on Degradation
[EN] The environmental problem generated by the massive consumption of plastics makes necessary the developing of biodegradable antimicrobial materials that can extend food shelf-life without having a negative impact on the environment. The current situation regarding the availability of biodegradable food packaging materials has been analysed, as well as different studies where antimicrobial compounds have been incorporated into the polymer matrix to control the growth of pathogenic or spoilage bacteria. Thus, the antimicrobial activity of active films based on different biodegradable polymers and antimicrobial compounds has been discussed. Likewise, relevant information on biodegradation studies carried out with different biopolymers in different environments (compost, soil, aquatic), and the effect of some antimicrobials on this behavior, are reviewed. In most of the studies, no relevant effect of the incorporated antimicrobials on the degradation of the polymer were observed, but some antimicrobials can delay the process. The changes in biodegradation pattern due to the presence of the antimicrobial are attributed to its influence on the microorganism population responsible for the process. More studies are required to know the specific influence of the antimicrobial compounds on the biodegradation behavior of polymers in different environments. No studies have been carried out or marine media to this end.This research was funded by Ministerio de Ciencia e Innovacion of Spain through the Project AGL2016-76699-R, PID2019-105207RB-I00, and the predoctoral research grant #BES-2017-082040.Hernandez-Garcia, E.; Vargas, M.; González Martínez, MC.; Chiralt Boix, MA. (2021). Biodegradable Antimicrobial Films for Food Packaging: Effect of Antimicrobials on Degradation. Foods. 10(6):1-23. https://doi.org/10.3390/foods1006125612310
Home built environment interventions and inflammation biomarkers: a systematic review and meta-analysis protocol
BACKGROUND: Inflammation control is a fundamental part of chronic care in patients with a history of cancer and comorbidity. As the risk-benefit profile of anti-inflammatory drugs in cancer survivors (CS) is unclear, GPs and patients could benefit from alternative non-pharmacological treatment options for dysregulated inflammation. There is a potential for home built environment (H-BE) interventions to modulate inflammation, however, discrepancies exist between studies. AIM: To evaluate the effectiveness of H-BE interventions on cancer-associated inflammation biomarkers. DESIGN & SETTING: A systematic review and meta-analysis of randomised and non-randomised trials in community-dwelling adults. METHOD: PubMed-Medline, Embase, Web of Science, and Google Scholar will be searched for clinical trials published in January 2000 onwards. We will include H-BE interventions modifying air quality, thermal comfort, non-ionising radiation, noise, nature and water. No restrictions to study population will be applied to allow deriving expectations for effects of the interventions in CS from available source populations. Outcome measures will be inflammatory biomarkers clinically and physiologically relevant to cancer. The first reviewer will independently screen articles together with GPs and extract data that will be verified by a second reviewer. The quality of studies will be assessed using the Cochrane Risk-of-Bias tools. Depending on the clinical and methodological homogeneity of populations, interventions, and outcomes, we will conduct a meta-analysis using random-effects models. CONCLUSIONS: Findings will determine the effectiveness of H-BE interventions on inflammatory parameters, guide future directions for its provision in community-dwelling CS and support GPs with safer anti-inflammatory treatment options in high-risk patients for clinical complications
Role of bacterial community composition as a driver of the small-sized phytoplankton community structure in a productive coastal system
Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGWe present here the first detailed description of the seasonal patterns in bacterial community composition (BCC) in shelf waters off the Ría de Vigo (Spain), based on monthly samplings during 2 years. Moreover, we studied the relationship between bacterial and small-sized eukaryotic community composition to identify potential biotic interactions among components of these two communities. Bacterial operational taxonomic unit (OTU) richness and diversity systematically peaked in autumn–winter, likely related to low resource availability during this period. BCC showed seasonal and vertical patterns, with Rhodobacteraceae and Flavobacteriaceae families dominating in surface waters, and SAR11 clade dominating at the base of the photic zone (30 m depth). BCC variability was significantly explained by environmental variables (e.g., temperature of water, solar radiation, or dissolved organic matter). Interestingly, a strong and significant correlation was found between BCC and small-sized eukaryotic community composition (ECC), which suggests that biotic interactions may play a major role as structuring factors of the microbial plankton in this productive area. In addition, co-occurrence network analyses revealed strong and significant, mostly positive, associations between bacteria and small-sized phytoplankton. Positive associations likely result from mutualistic relationships (e.g., between Dinophyceae and Rhodobacteraceae), while some negative correlations suggest antagonistic interactions (e.g., between Pseudo-nitzchia sp. and SAR11). These results support the key role of biotic interactions as structuring factors of the small-sized eukaryotic community, mostly driven by positive associations between small-sized phytoplankton and bacteria.Xunta de Galicia | Ref. EM2013/023Xunta de Galicia | Ref. ED481A-2019/290Xunta de Galicia | Ref. ED431I 2020/03Ministerio de Economía y Competitividad | Ref. CTM2017-83362-RMinisterio de Ciencia e Innovación | Ref. PID2019-110011RB-C3
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