809 research outputs found
Advances in troubleshooting fish and seafood authentication by inorganic elemental composition
The demand for fish and seafood is growing worldwide. Meanwhile, problems related to the integrity and safety of the fishery sector are increasing, leading legislators, producers, and consumers to search for ways to effectively protect themselves from fraud and health hazards related to fish consumption. What is urgently required now is the availability of reliable, truthful, and reproducible methods assuring the correspondence between the real nature of the product and label declarations accompanying the same product during its market life. The evaluation of the inorganic composition of fish and seafood appears to be one of the most promising strategies to be exploited in the near future to assist routine and official monitoring operations along the supply chain. The present review article focuses on exploring the latest scientific achievements of using the multi-elemental composition of fish and seafood as an imprint of their authenticity and traceability, especially with regards to the geographical origin. The scientific literature of the last 10 years focusing on the analytical determination and statistical elaboration of elemental data (alone or in combination with methodologies targeting other compounds) to verify the identity of fishery products is summarized and discussed
Challenges in Additive Manufacturing of space parts: Powder feedstock cross-contamination and its impact on end products
This work studies the tensile properties of Ti-6Al-4V samples produced by laser powder bed based Additive Manufacturing (AM), for different build orientations. The results showed high scattering of the yield and tensile strength and low fracture elongation. The subsequent fractographic investigation revealed the presence of tungsten particles on the fracture surface. Hence, its detection and impact on tensile properties of AM Ti-6Al-4V were investigated. X-ray Computed Tomography (X-ray CT) scanning indicated that these inclusions were evenly distributed throughout the samples, however the inclusions area was shown to be larger in the load-bearing plane for the vertical specimens. A microstructural study proved that the mostly spherical tungsten particles were embedded in the fully martensitic Ti-6Al-4V AM material. The particle size distribution, the flowability and the morphology of the powder feedstock were investigated and appeared to be in line with observations from other studies. X-ray CT scanning of the powder however made the high density particles visible, where various techniques, commonly used in the certification of powder feedstock, failed to detect the contaminant. As the detection of cross contamination in the powder feedstock proves to be challenging, the use of only one type of powder per AM equipment is recommended for critical applications such as Space parts. 2017 by the authors
Further probing of Cu 2+ -dependent PNAzymes acting as artificial RNA restriction enzymes
Peptide nucleic acid (PNA)-neocuproine conjugates have been shown to efficiently catalyse the cleavage of RNA target sequences in the presence of Cu2+ ions in a site-specific manner. These artificial enzymes are designed to force the formation of a bulge in the RNA target, the sequence of which has been shown to be key to the catalytic activity. Here, we present a further investigation into the action of Cu2+-dependent PNAzymes with respect to the dependence on bulge composition in 3- and 4-nucleotide bulge systems. Cu2+-dependent PNAzymes were shown to have a clear preference for 4-nucleotide bulges, as the cleavage of 3-nucleotide bulge-forming RNA sequences was significantly slower, which is illustrated by a shift in the half-lives from approximately 30 min to 24 h. Nonetheless, the nucleotide preferences at different positions in the bulge displayed similar trends in both systems. Moreover, the cleavage site was probed by introducing critical chemical modifications to one of the cleavage site nucleotides of the fastest cleaved 4-nucleotide RNA bulge. Namely, the exclusion of the exocyclic amine of the central adenine and the replacement of the 2′-hydroxyl nucleophile with 2′-H or 2′-OMe substituents in the RNA severely diminished the rate of RNA cleavage by the Cu2+-dependent PNAzyme, giving insight into the mechanism of cleavage. Moreover, the shorter recognition arm of the RNA/PNAzyme complex was modified by extending the PNAzyme by two additional nucleobases. The new PNAzyme was able to efficiently promote the cleavage of RNA when fully hybridised to a longer RNA target and even outperform the previous fastest PNAzyme. The improvement was demonstrated in cleavage studies with stoichiometric amounts of either PNAzyme present, and the extended PNAzyme was also shown to give turnover with a 10-fold excess of the RNA target
Giant and reversible extrinsic magnetocaloric effects in La0.7Ca0.3MnO3 films due to strain
Large thermal changes driven by a magnetic field have been proposed for
environmentally friendly energy efficient refrigeration, but only a few
materials which suffer hysteresis show these giant magnetocaloric effects. Here
we create giant and reversible extrinsic magnetocaloric effects in epitaxial
films of the ferromagnetic manganite La0.7Ca0.3MnO3 using strain mediated
feedback from BaTiO3 substrates near a first-order structural phase transition.
Our findings should inspire the discovery of giant magnetocaloric effects in a
wide range of magnetic materials, and the parallel development of
nanostructured bulk samples for practical applications.Comment: 32 pages, 1 Table, 5 figures, supplementary informatio
Differences in code terminology and frequency of findings in meat inspection of finishing pigs in seven European countries
The overall objectives of meat inspection are to contribute to food safety, animal welfare, and animal health. In the European Union (EU), there is a request for a modernised meat inspection system that addresses these objectives in a more valid, feasible and cost-effective way than does the traditional system. One part of the modernisation deals with the coding system to register meat inspection findings. Although unified standards are set at the EU level for judgement criteria regarding fitness of meat for consumption, different national systems are in force. The question is the extent of the differences and whether there is a basis for harmonisation. To investigate this, information was gathered about the code systems in Denmark, Finland, Germany, Italy, Norway, Portugal and Spain. Moreover, meat inspection data covering pigs slaughtered in 2019 were collected. A comparison of the number of codes available, the terminology and the frequencies of the findings registered was undertaken. Codes with a similar meaning were grouped. Hereby, two lists were compiled showing the most common codes leading to total and to partial condemnation. Substantial variations in the percentage of condemned pigs and in the terms used were identified, and possible reasons behind this are discussed. Moreover, a strengths-weaknesses-opportunities-threats (SWOT)-like analysis was applied to the coding systems. Finally, the reasons for unfitness of meat given in the EU Food Inspection Regulation 2019/627 were compared to the national code lists. The results show the systems in force varied substantially, and each system had its advantages and disadvantages. The diverse terminology observed made it a challenge to compare data between countries. Development of harmonised terminology for meat inspection findings is suggested, enabling comparison of data between abattoirs, regions, and countries, while respecting the national epidemiological situation, the local food safety culture, and the trade agreements in force.Peer reviewe
Differences in code terminology and frequency of findings in meat inspection of finishing pigs in seven European countries
The overall objectives of meat inspection are to contribute to food safety, animal welfare, and animal health. In the European Union (EU), there is a request for a modernised meat inspection system that addresses these objectives in a more valid, feasible and cost-effective way than does the traditional system. One part of the modernisation deals with the coding system to register meat inspection findings. Although unified standards are set at the EU level for judgement criteria regarding fitness of meat for consumption, different national systems are in force. The question is the extent of the differences and whether there is a basis for harmonisation. To investigate this, information was gathered about the code systems in Denmark, Finland, Germany, Italy, Norway, Portugal and Spain. Moreover, meat inspection data covering pigs slaughtered in 2019 were collected. A comparison of the number of codes available, the terminology and the frequencies of the findings registered was undertaken. Codes with a similar meaning were grouped. Hereby, two lists were compiled showing the most common codes leading to total and to partial condemnation. Substantial variations in the percentage of condemned pigs and in the terms used were identified, and possible reasons behind this are discussed. Moreover, a strengths-weaknesses-opportunities-threats (SWOT)-like analysis was applied to the coding systems. Finally, the reasons for unfitness of meat given in the EU Food Inspection Regulation 2019/627 were compared to the national code lists. The results show the systems in force varied substantially, and each system had its advantages and disadvantages. The diverse terminology observed made it a challenge to compare data between countries. Development of harmonised terminology for meat inspection findings is suggested, enabling comparison of data between abattoirs, regions, and countries, while respecting the national epidemiological situation, the local food safety culture, and the trade agreements in force
Influenza delle condizioni di conservazione sulla qualità e sulla stabilità nel tempo di filetti di alici sott’olio.
The overall quality of semi-preserved anchovy fillets in oil is strongly dependent on the quality of the catch as well as on the manufacturing processes adopted by the fishing industry. The enzymatic processes underlying the fish ripening tend to remain also during the storage, especially if holding temperatures and packaging materials are inappropriate, thus being potentially responsible for the rapid loss of the sensorial properties of the fish product. In the present work the modification over time of different qualitative parameters of samples of anchovy fillets in oil stored in different packaging materials (glass and plastic) and at different temperatures (18 and 28°C) was instrumentally evaluated. The exposure to high temperature determined a rapid and widespread deterioration of the anchovy fillets, while no significant packaging-dependent modification of the organoleptic quality of the fish were identified
New results from the NA57 experiment
We report results from the experiment NA57 at CERN SPS on hyperon production
at midrapidity in Pb-Pb collisions at 158 GeV/ and 40 GeV/.
, and yields are compared with those from the STAR
experiment at the higher energy of the BNL RHIC. , , \
and preliminary transverse mass spectra are presented and interpreted
within the framework of a hydro-dynamical blast wave model.Comment: 8 pages, 3 figures, contribution to the proceedings of The XXXVIIIth
Rencontres de Moriond "QCD and High Energy Hadronic Interactions
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