99 research outputs found
Portal Vein Aneurysm Mimicking a Liver Nodule
info:eu-repo/semantics/publishedVersio
Evaluation of two packaging systems for regional cheese
Saloio cheese – a regional Portuguese cheese – is currently sold unpackaged or in a vacuum package. Neither of these packaging systems is acceptable: the first system yields a cheese too hard, because of excessive water loss, while the second yields a white cheese with poor textural properties. The use of a packaging system with a tailor-made moisture barrier, i.e., allowing for water loss, but at a lower
rate, is a way of extending the cheese’s shelf-life. The adequate water vapour permeability to preserve the cheese was previously determined as 6.8 · 107 g m/m2day Pa at 8 C. The objective of this work was to develop a packaging system providing the required relative humidity inside the package. Two systems were tested: (i) the active system Humidipak and (ii) perforated plastic films. Both packaging systems succeeded in extending the cheese’s shelf-life by significantly decreasing the water loss. Perforated films require further study on moulds growth control
Performance of wine bag-in-box during storage: loss of oxygen barrier
Bag-in-box system is a convenient packaging system for wine. Its barrier to
oxygen relies, in many cases, in an aluminium metallized polyester film laminated
between two polyethylene (PE) layers as the inner bag. One on the most frequently
observed system failures is the ingress of wine into the gap between the layers of
the double bag. This study aimed at verifying if that influences the barrier of the
system to oxygen. The results showed that the contact of wine with this barrier
layer, although through a PE layer, promotes the demetallization and consequent
loss of barrier properties. The type of wine, in particular its volatile acidity, and the
temperatures were two variables assessed. Results showed that wine with higher
acidity and stored at higher temperatures tend to yield a higher increase in oxygen
transmission rate of the film.info:eu-repo/semantics/publishedVersio
Feasibility study on the use of probabilistic migration modeling in support of exposure assessment from food contact materials
The use of probabilistic approaches in exposure assessments of contaminants migrating from food packages is of increasing interest but the lack of concentration or migration data is often
referred as a limitation. Data accounting for the variability and uncertainty that can be expected in migration, for example, due to heterogeneity in the packaging system, variation of the temperature along the distribution chain, and different time of consumption of each individual package, are required for probabilistic analysis. The objective of this work was to characterize quantitatively the uncertainty and variability in estimates of migration. AMonte
Carlo simulation was applied to a typical solution of the Fick’s law with given variability in the input parameters. The analysis was performed based on experimental data of a model system (migration of Irgafos 168 from polyethylene into isooctane) and illustrates how important sources of variability and uncertainty can be identified in order to refine analyses.
For long migration times and controlled conditions of temperature the affinity of the migrant to the food can be the major factor determining the variability in the migration values (more than 70% of variance). In situations where both the time of consumption and temperature can vary, these factors can be responsible, respectively, for more than 60% and 20% of the variance in the migration estimates. The approach presented can be used with databases from consumption surveys to yield a true probabilistic estimate of exposure.info:eu-repo/semantics/acceptedVersio
Nanocellulose bio-based composites for food packaging
The food industry is increasingly demanding advanced and eco-friendly sustainable packaging materials with improved physical, mechanical and barrier properties. The currently used materials are synthetic and non-degradable, therefore raising environmental concerns. Consequently, research efforts have been made in recent years towards the development of bio-based sustainable packaging materials. In this review, the potential of nanocelluloses as nanofillers or as coatings for the development of bio-based nanocomposites is discussed, namely: (i) the physico-chemical interaction of nanocellulose with the adjacent polymeric phase, (ii) the effect of nanocellulose modification/functionalization on the final properties of the composites, (iii) the production methods for such composites, and (iv) the effect of nanocellulose on the overall migration, toxicity, and the potential risk to human health. Lastly, the technology readiness level of nanocellulose and nanocellulose based composites for the market of food packaging is discussed.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.” The authors also acknowledge the financial support of the FCT (ESF) through the grant given to Francisco A.G.S. Silva (SFRH/BD/146375/2019).info:eu-repo/semantics/publishedVersio
Mediastinal Mass in a Patient with Colorectal Cancer: A Diagnostic Challenge
The differential diagnosis of mediastinal masses involves many benign and malignant conditions, such as lymphadenopathies and cystic lesions. Metastatic mediastinal adenopathies are usually due to lung, esophagus, and stomach cancer and, rarely, due to colorectal cancer. Gastrointestinal duplication cysts are uncommon inherited lesions usually diagnosed during childhood and may involve the esophagus in 20% of cases. In adults, they are usually asymptomatic and diagnosed incidentally. We report the case of a 54-year-old male who recently underwent sigmoidectomy due to an obstructive colon adenocarcinoma. Staging computed tomography scan showed a hypodense lesion in the posterior mediastinum suggestive of metastatic adenopathy. Endoscopic ultrasound revealed a homogeneous and hypoechogenic lesion with intramural location in the upper esophagus, suggestive of a duplication esophageal cyst. Given the oncologic background and to exclude metastatic disease, endoscopic ultrasound-guided fine needle aspiration was performed, and a mucinous fluid was aspirated. The cytologic examination supported the ultrasonographic diagnostic hypothesis. This case highlights the role of endoscopic ultrasound in the differential diagnosis of mediastinal masses, particularly in oncologic patients, in order to rule out more ominous lesions.info:eu-repo/semantics/publishedVersio
Development of bacterial cellulose composites for food packaging and textiles
Most of all petroleum-based materials are used for a short period of time but then take centuries to degrade. Food packaging and textile are examples of industries that are truly dependent of synthetic materials. Therefore, there is an increasing interest on seeking alternatives to these materials. Plant nanocellulose (PNC) has been actively studied, yet the high demand may arise environmental issues such deforestation and wood processing. An alternative source is bacterial cellulose (BC), produced by bacteria of the genus Komagataeibacter, through fermentation. BC has a great potential due to great mechanical performance, despite some drawbacks such high water affinity (for food packaging) and high molecular weight (for textiles). Different approaches were used with the attempt to reduce water vapor permeability and functionalize BC based composite for Food packaging. For textiles, highly performing fibres were developed after using adapted Lyocell and Ioncell technologies.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, BIOPROTECT - Development of Biodegradable Packaging Material with Active Properties for Food Preservation POCI-01-0247-FEDER-069858, COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional DevelopmentFund under the scope of Norte2020 - Programa Operacional Regional do Norte.” The authors also acknowledge the financial support of the FCT (ESF) through the grant given to Francisco A.G.S. Silva (SFRH/BD/146375/2019). The authors also thank all the support given by the Thuringian Institute for Textile and Plastics Research (TITK) and the department of Bioproducts and Biosystems at Aalto University. The authors also thank the support of Aquitex - Acabamentos Químicos Têxteis, S.A.info:eu-repo/semantics/publishedVersio
Duodenal gastrointestinal stromal tumor and endoscopic ultrasound
Duodenal gastrointestinal stromal tumors (GISTs) are a very rare condition. The pre-operative diagnosis can be a challenge but it is very important because GISTs have singularities that differ from other tumors and their location in the duodenum itself can have a major role in the choice of the surgical approach. We present two cases of duodenal GISTs where endoscopic ultrasound had a single role in their management, namely allowing the possibility to obtain material for immunocytochemical pre-operative diagnosis and regarding the precise relation to the papilla of Vater. The patients were operated and histological examination confirmed the diagnosis in both cases
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