1,034 research outputs found
Cork Core Sandwich Plates for Blast Protection
This article belongs to the Special Issue Armour and Protection SystemsA numerical model is developed and validated to analyse the performance of aluminium skin and agglomerated cork core sandwich plates subjected to blast loads. Two numerical approaches are used and thoroughly compared to generate the blast loading: an Arbitrary-Lagrangian–Eulerian approach and the Load Blast Enhanced method. Both of the models are validated by comparing the numerical results with experimental observations. A detailed analysis of the sandwich behaviour is done for both approaches showing small differences regarding the mechanical response of the sandwich structure. The results obtained from the numerical models uncover the specific energy absorption mechanisms happening within the sandwich plate components. A new core topology is proposed, based on these results, which maximises the energy absorption capacity of the plate, keeping the areal density unchanged. A wavy agglomerated cork core is proposed and the effects of different geometrical parameters on the energy absorption are thoroughly analysed and discussed. The proposed optimised plate configuration shows an increase in the total absorbed energy of close to 40% relative to a reference case with the same areal density. The adopted optimisation methodology can be applied to alternative configurations to increase the performance of sandwich structures under blast events.This research was funded by Ministerio de Economía y Competitividad, Gobierno de España grant number DPI2017-85073-R, and Universidad Carlos III of Madrid grant numbers 2013/00413/003 and 2014/00006/002. And the travel expenses were funded by Universidad Carlos III de Madrid grant number Programa propio de investigación-Convocatoria 2014 movilidad
Use of galactomannan edible coating application and storage temperature for prolonging shelf-life of “regional” cheese
The objectives of this work were to determine the influence of the application of two different coatings (galactomannan and chitosan) and of storage temperature on the gas exchange rate of “Regional” cheese; subsequently, the coating that showed the greatest influence on the cheese gas exchange and simultaneously decreased the O2 consumption (RO2) and the CO2 production (RCO2) rates was applied on cheese, being the shelf-life parameters monitorized through the performance of chemical and microbiological analyses. Both coatings caused a reduction of RO2 and RCO2 of the cheese (between 0.19- and 1.30-fold for RO2 and between 0.19- and 1.50-fold for RCO2, depending on the temperatures). The cheese coated with the galactomannan coating was the one with the lower values of RO2 (between 0.195 and 0.635 mL kg−1 h−1) and RCO2 (between 0.125 and 0.900 mL kg−1 h−1). Temperature was also found to have an important effect on RO2 and RCO2, its influence being well described by an Arrhenius equation with coefficients of determination, R2, of 0.85 and above. The chemical and microbiological analyses showed that the application of the coating in cheese samples can be used to decrease the water loss and the colour changes during the storage time. The presence of the coating decreased the moisture loss of the cheese in 2.5% and 1.9%, and the weight loss in 3.8% and 3.1% at 4 °C and 20 °C, respectively. Also, the hardness of the cheese can be decreased as a result of the interaction of the presence of the coating with changes in the storing temperature. In the studied range (4–20 °C) temperature has a statistically significant effect in moisture loss, colour change, hardness and total mesophilic bacterial growth.
Overall, galactomannan coating can be used to improve “Regional” cheese shelf-life as it decreases RO2 and RCO2, improves its weight and appearance and can be used to incorporate natural preservatives to reduce post contamination.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brazil (Capes, Brazil)Queijo Saloio S.A.Fundação para a Ciência e a Tecnologia (FCT
Ohmic heating in a food application: quality evaluation of cloudberry jam
New techniques for food processing are areas of interest for the food industry and ohmic heating is an example of a new technique where there are many possible applications in the food area.
The aim of this work was to characterize and compare quality aspects of high quality cloudberry jam with 70 weight-% berries produced on one hand by traditional batch processing technique and on the other hand by ohmic heating in a continuous process. Sensory analysis was performed on
the two jams by a trained panel. In order to investigate the consumer opinions in different countries a consumer study was performed including 402 consumers from the four countries Sweden, Portugal, Ireland and Slovakia. Rheological properties of the jam were also measured. The results
showed that there were no significant differences for any of the sensory attributes between the jam produced by traditional technique and the jam produced by ohmic heating. The results from the consumer study showed that in all four countries, the appearance, odour, flavour, texture, aftertaste
and overall quality of both jams were liked to the same extent. However, differences in liking cloudberry jam differed between the participating countries. The Swedish and the Portuguese consumers were in general giving higher scores on the liking of the cloudberry jams than the Slovakian and Irish consumers. There were no differences found between the two jams according to the rheological properties of the samples. The results indicated that it was possible to maintain
the same quality of cloudberry jam produced by ohmic heating as of cloudberry jam produced in a traditional way
Subsystems for future access networks
Current evolution and tendencies of Telecom Networks in general and more specifically optical Metro and Access Networks and their convergence are reported. Based on this evolution, a set of research lines are foreseen regarding subsystems and devices as: high speed optical sources, modulators and receivers, for the next generation of Passive Optical Networks. The ICT project EURO-FOS is achieving European level cooperative research among academia and industry, enabling future telecommunication networks
Gallic acid production with mouldy polyurethane particles obtained from solid state culture of Aspergillus niger GH1
Gallic acid production in a batch bioreactor was evaluated using as catalytic material the mouldy polyurethane solids (MPS) obtained from a solid-state fermentation (SSF) bioprocess carried out for tannase production by Aspergillus niger GH1 on polyurethane foam powder (PUF) with 5 % (v/w) of tannic acid as inducer. Fungal biomass, tannic acid consumption and tannase production were kinetically monitored. SSF was stopped when tannase activity reached its maximum level. Effects of washing with distilled water and drying on the tannase activity of MPS were determined. Better results were obtained with dried and washed MPS retaining 84 % of the tannase activity. Maximum tannase activity produced through SSF after 24 h of incubation was equivalent to 130 U/gS with a specific activity of 36 U/mg. The methylgallate was hydrolysed (45 %) in an easy, cheap and fast bioprocess (30 min). Kinetic parameters of tannase self-immobilized on polyurethane particles were calculated to be 5 mM and 04.1×102 mM/min for K M and V max, respectively. Results demonstrated that the MPS, with tannase activity, can be successfully used for the production of the antioxidant gallic acid from methyl-gallate substrate. Direct use of PMS to produce gallic acid can be advantageous as no previous extraction of enzyme is required, thus reducing production costs.Authors thank the National Council for Science and Technology (CONACYT-Mexico) for the financial support. The present work was performed as part of a cooperative agreement between DIA-Universidad Autonoma de Coahuila (Mexico) and IBB-Universidade do Minho (Portugal) within a specific training stay undertaken at the DEB-UM. Part of the research was funded by a project SEP-CONACYT-CB-2011
Evaluation of grape stems and grape stem extracts for sulfur dioxide replacement during grape wine production
Supplementary data to this article can be found online at https://doi.org/10.1016/j.crfs.2023.100453.Sulfur dioxide (SO2), the main preservative in wine, may affect the sensory properties of the wines, as well as cause allergic reactions and headaches in sensitive people. The aim of this work was to evaluate the replacement of SO2 in Tempranillo wines with Mazuelo grape stem products. Five Tempranillo red wines were elaborated: positive control (60 mg/L SO2); negative control with no preservatives; Mazuelo extract (200 mg/L); Mazuelo extract combined with SO2 (100 mg/L + 20 mg/L); and Mazuelo stem (400 mg/L). The oenological parameters, antioxidant capacity, total phenolic (TP), total flavonoids (TF) and total anthocyanins (TA) contents were determined. Additionally, individual phenols were analyzed by HPLC-DAD-FLD. The spectrophotometric analyses showed that the wines had similar antioxidant capacities and concentrations of TP and TF. However, TA was more affected by the lack of SO2 as anthocyanins presented higher concentrations in positive control samples. The concentrations of individual phenols followed a similar path in all samples. Wines containing sulfites were more similar than the other treatments. However, these similarities were not reflected on the sensory analysis performed, as triangle test did not show differences between the wine with extract addition and the positive control wine. Therefore, Mazuelo stem extract could be a possible strategy for SO2 replacement. Nevertheless, further studies are necessary to confirm the potential of grape stem extracts as wine preservative.This study was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, and by the European Regional Development Fund (ERDF) through the Competitiveness factors Operational program – Norte 2020, COMPETE and by National Funds through the FCT - under the project AgriFood XXI (NORTE- 01-0145-FEDER-000041).info:eu-repo/semantics/publishedVersio
A multi-wavelength census of stellar contents in the young cluster NGC 1624
We present a comprehensive multi-wavelength analysis of the young cluster NGC
1624 associated with the H II region Sh2-212 using optical UBVRI photometry,
optical spectroscopy and GMRT radio continuum mapping along with the
near-infrared (NIR) JHK archival data. Reddening E(B-V) and distance to the
cluster are estimated to be 0.76 - 1.00 mag and 6.0 +/- 0.8 kpc, respectively.
Present analysis yields a spectral class of O6.5V for the main ionizing source
of the region. The distribution of YSOs in (J-H)/ (H-K) NIR colour-colour
diagram shows that a majority of them have A_V 4 mag. Based on the NIR
excess characteristics, we identified 120 probable candidate YSOs in this
region which yield a disk frequency of ~ 20%. These YSOs are found to have an
age spread of ~ 5 Myr with a median age of ~ 2-3 Myr and a mass range of ~ 0.1
- 3.0 . A significant number of YSOs are located close to the cluster
centre and we detect an enhanced density of reddened YSOs located/projected
close to the molecular clumps at the periphery of NGC 1624. This indicates that
the YSOs located within the cluster core are relatively older in comparison to
those located/projected near the clumps. From the radio continuum flux,
spectral class of the ionizing source of the ultra-compact H II region at the
periphery of Sh2-212 is estimated to be ~ B0.5V. From optical data, slope of
the mass function (MF) , in the mass range can
be represented by a single power law with a slope -1.18 +/- 0.10, whereas the
NIR data in the mass range yields = -1.31
+/- 0.15. The slope of the K-band luminosity function (KLF) for the cluster is
found to be 0.30 +/- 0.06 which is in agreement with the values obtained for
other young clusters.Comment: Accepted for publication in MNRA
Cocoa coproducts-based and walnut oil gelled emulsion as animal fat replacer and healthy bioactive source in beef burgers
The aim of this work was to evaluate the effects on the chemical, physic-chemical, tech-nological, and sensory properties of beef burger when replacing different quantities of fat (50 and 100%) with different levels of oil-in-water-gelled emulsion elaborated with walnut oil and cocoa bean shell flour (GECW). The chemical composition of the samples was affected by the fat replace-ment. The reformulation increased the moisture and ash content while the fat and protein content decreased with respect to the control sample. The linolenic and linolenic acid content of the beef burgers increased as the GECW replacement was augmented. The polyunsaturated fatty/saturated fatty acid ratio increased in both raw and cooked burgers, whereas the atherogenicity index and thrombogenicity index were reduced in both raw and cooked burgers with respect to the control sample. The use of GECW as a fat replacer was found to be effective in improving the cooking loss. Similarly, there were positive effects on reductions in the diameter and the increases in the thickness of the beef burgers. Regarding lipid stability, in both the raw and cooked burgers, the reformulation increased the 2-thiobarbituric acid reactive substance (TBARs) values with respect to the control sample. In both types of reformulated burgers, three bound polyphenols (mainly catechin and epicatechin) and two free polyphenols were identified, as were methylxanthines theobromine and caffeine. The sensory properties for the control and partial pork backfat replacement treatments were similar, while the sample with the total pork backfat replacement treatment showed the lowest scores. The blend of cocoa bean shell flour and walnut oil could be used as new ingredients for the development of beef burgers with a healthier nutritional profile without demeriting their sensory or cooking characteristics and physic-chemical properties.This research was funded by Programa Iberoamericano de Ciencia y Tecnología para el
Desarrollo CYTED: 119RT0568.info:eu-repo/semantics/publishedVersio
Immobilization and application of the recombinant xylanase GH10 of Malbranchea pulchella in the production of xylooligosaccharides from hydrothermal liquor of the eucalyptus (Eucalyptus grandis) wood chips
Xylooligosaccharides (XOS) are widely used in the food industry as prebiotic components. XOS with high purity are required for practical prebiotic function and other biological benefits, such as antioxidant and inflammatory properties. In this work, we immobilized the recombinant endo-1,4-β-xylanase of Malbranchea pulchella (MpXyn10) in various chemical supports and evaluated its potential to produce xylooligosaccharides (XOS) from hydrothermal liquor of eucalyptus wood chips. Values >90% of immobilization yields were achieved from amino-activated supports for 120 min. The highest recovery values were found on Purolite (142%) and MANAE-MpXyn10 (137%) derivatives, which maintained more than 90% residual activity for 24 h at 70 °C, while the free-MpXyn10 maintained only 11%. In addition, active MpXyn10 derivatives were stable in the range of pH 4.0–6.0 and the presence of the furfural and HMF compounds. MpXyn10 derivatives were tested to produce XOS from xylan of various sources. Maximum values were observed for birchwood xylan at 8.6 mg mL−1 and wheat arabinoxylan at 8.9 mg mL−1, using Purolite-MpXyn10. Its derivative was also successfully applied in the hydrolysis of soluble xylan present in hydrothermal liquor, with 0.9 mg mL−1 of XOS after 3 h at 50 °C. This derivative maintained more than 80% XOS yield after six cycles of the assay. The results obtained provide a basis for the application of immobilized MpXyn10 to produce XOS with high purity and other high-value-added products in the lignocellulosic biorefinery field.The authors gratefully acknowledge FAPESP (São Paulo Research Foundation, grants No: 2018/07522-6) and FCT (POCI-01-0145-FEDER-032206)—transnational cooperation project EcoTech, and National Institute of Science and Technology of Bioethanol, INCT, CNPq 465319/2014-9/FAPESP n ◦ 2014/50884- 5) for financial support. Research scholarships were granted to RCA, DA, and JCSS by FAPESP (Grant No: 2020/00081-4, 2020/15510-8, and 2019/21989-7, respectively), to CCVD and VEP by CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Finance Code 001).info:eu-repo/semantics/publishedVersio
Metabolomics applied to maternal and perinatal health: a review of new frontiers with a translation potential
The prediction or early diagnosis of maternal complications is challenging mostly because the main conditions, such as preeclampsia, preterm birth, fetal growth restriction, and gestational diabetes mellitus, are complex syndromes with multiple underlying mechanisms related to their occurrence. Limited advances in maternal and perinatal health in recent decades with respect to preventing these disorders have led to new approaches, and "omics" sciences have emerged as a potential field to be explored. Metabolomics is the study of a set of metabolites in a given sample and can represent the metabolic functioning of a cell, tissue or organism. Metabolomics has some advantages over genomics, transcriptomics, and proteomics, as metabolites are the final result of the interactions of genes, RNAs and proteins. Considering the recent "boom" in metabolomic studies and their importance in the research agenda, we here review the topic, explaining the rationale and theory of the metabolomic approach in different areas of maternal and perinatal health research for clinical practitioners. We also demonstrate the main exploratory studies of these maternal complications, commenting on their promising findings. The potential translational application of metabolomic studies, especially for the identification of predictive biomarkers, is supported by the current findings, although they require external validation in larger datasets and with alternative methodologies.74CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESSem informação88881.134095/2016-01; 8881.134512/2016-0
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