Ageing of large cuts of beef loin in vacuum or high oxygen modified atmosphere – Effect on shear force,calpain activity,desmin degradation and protein oxidation

The aim was to investigate the effect of ageing large beef cuts directly in high oxygen modified atmosphere (MA) and how ageing time in vacuum influence meat quality when followed by retail packaging in high oxygen MA. Large cuts (10 cm long) of beef loin (LD) were aged for up to 25 days postmortem in different ageing systems at 4 °C. Ageing solely in high oxygen modified atmosphere (MA, 80% O₂ + 20% CO₂) for 5 or 10 days and ageing in vacuum for 5 or 15 days followed by high oxygen MA for 5 or 10 days were compared with ageing in vacuum for 5, 15 and 25 days. Warner–Bratzler shear force, purge and cooking losses, calpain activity and desmin and carbonyl contents were measured. Shear force decreased to the same level when ageing this large beef cut solely in high oxygen MA for 5 or 10 days as when ageing in vacuum. The activity of μ-calpain disappeared, the activity of m-calpain decreased and purge loss increased between 5 and 10 days, but cooking loss and the contents of desmin and carbonyls were unaffected. The ageing time in vacuum before packaging of this large beef cut in high oxygen MA did not affect the ultimate shear force. The m-calpain activity decreased and the content of carbonyls increased compared with solely in vacuum after 15 days of total ageing, but there was no difference in the content of desmin or cooking loss between these ageing systems at the same ageing time.     

Who leaves rental housing? Examining possible explanations for ethnic housing segmentation in Uppsala,Sweden

Swedish cities are not only segregated but also segmented along ethnic lines; i.e., different ethnic groups are unevenly distributed across the different tenure segments in the housing market. Immigrants are generally overrepresented in rental housing and underrepresented in home ownership and tenant–owner cooperative housing. In this paper, an attempt is made to evaluate the importance of socioeconomic resources in explaining this segmentation, using the Uppsala housing market as a case. By means of binary logistic regression an evaluation is made of the relative importance of socioeconomic resources and ethnic background, while controlling for demographic factors, in explaining whether a person leaves rental housing for home ownership or cooperative housing or remains in the rental segment. The results show that the socioeconomic situation of the individual is indeed very important. A high income and a stable position in the labor market seem to be crucial in order to advance in the housing market. Demographic and socioeconomic factors cannot, however, fully account for the differences found between Swedes and immigrant groups such as Africans and Eastern Europeans. The results imply that ethnic discrimination cannot be ruled out as an explanation for the underrepresentation of immigrants in the cooperative and owner-occupied segments.     

Cholesterol oxides in Swedish food and food ingredients: Lard and bacon

Lard samples, manufactured from adipose tissue, were found to contain traces and/or quantifiable concentrations of certain cholesterol oxides, viz., 5α-, 6α-epoxycholestanol, 7-ketocholesterol, 7α-hydroxycholesterol, 20α-hydroxycholesterol and 25-hydroxycholesterol at the detection limit 0.1 ppm. The influence of steam refining and chemical refining on the cholesterol oxide levels in a few of the crude lard samples was investigated. The analyses showed that these processes had no appreciable effect on the concentrations of cholesterol oxides, compared with the controls. Analysis of cold-stored consumer packages of lard (2-mo old up to 18-mo old samples) indicated that there were no differences in the pattern of cholesterol oxides. On the other hand, storage of refined superior and regular grade lard samples at 50°C for up to 18 days caused only a slight increase in the levels of the isomeric 5,6-epoxycholestanols. Raw bacon, bacon fried at 170°C for 10 and 20 min and bacon dripping were analyzed. The analyses showed that quantifiable levels of 5α-,6α-epoxycholestanol, C-7 oxidation derivatives of cholesterol and 25-hydroxycholesterol could be detected only in the fried rind. A substantial amount (about 0.5 ppm) of a cholesterol metabolite was detected in the lard samples. Its identification as 7α-hydroxycholest-4-en-3-one was based on the comparison of RRT value and mass spectral information, as TMS-ether, to that of synthetic 7α-hydroxycholest-4-en-3-one.     

外军ATE/ATS技术的发展趋势

介绍了外军ATE／ATS技术的发展过程，重点分析了美军，法军ATE／ATS技术发展的现状，阐述了军用ATE／ATS技术未来的发展趋势。     

Identifying and Exploring Synthetic Antiferromagnetic Skyrmions

Synthetic antiferromagnetic (SAF) skyrmions are emerging as novel information carriers due to their high mobility and lack of a skyrmion Hall effect. However, distinguishing SAF skyrmions from their ferromagnetic counterparts using imaging techniques like magneto-optical microscopy remains challenging. While the suppressed intrinsic skyrmion Hall effect (SkHE) has been commonly used to identify SAF skyrmions, it is important to note that other factors such as defect pinning and dipolar interaction can also lead to a suppressed SkHE. Therefore, there is an urgent need for a universal identification method that can reliably differentiate SAF skyrmions from ferromagnetic ones. In this study, the generation of a SAF skyrmion within a standard SAF stack is demonstrated and its motion with almost no SkHE is investigated. Furthermore, a universal identification method is proposed wherein the application of an out-of-plane field allows the SAF skyrmion to be decoupled into two domains, which can either expand or contract with the application of an electric current. By expediting the development of a reliable means of identifying SAF skyrmions, these findings will accelerate the realization of practical applications based on these unique information carriers.     

The catalytic activity of the Pr2Zr2−xFexO7±δ system for the CO oxidation reaction

One of the alternatives to decrease the concentration of CO is its oxidation reaction to CO₂, which can be made more efficient using catalysts. In this work, it is shown that pyrochlore structures are a promising candidate to act as heterogeneous catalysts due to their chemical and physical properties. For use as a catalyst in this reaction, the Pr₂Zr_2−xFe_xO_7±δ (x = 0, 0.05, 0.10, and 0.15) system was synthesized by the solvothermal method, firing the powder obtained at temperatures of 1200 and 1400°C. The diffraction patterns confirmed the pyrochlore structure as the single phase in all the nominal compositions. The Brunauer–Emmett–Teller method and dynamic light-scattering analysis showed an increase in the particle size and a decrease in the specific surface area when increasing the iron concentration and increasing the calcination temperature. The compositions that presented the best catalytic activity were the samples with the highest iron concentration. Moreover, these samples were able to convert all the CO oxidation reactions in a narrower temperature range than a conventional CeO₂ sample. The presence of vacancies and the redox behavior of the elements present are the key factors for the catalysis of this system in the CO oxidation reaction.     

Drug-Derived Surface-Active Ionic Liquids: A Cost-Effective Way To Expressively Increase the Blood-Stage Antimalarial Activity of Primaquine

Inspired by previous disclosure of room-temperature ionic liquids derived from primaquine and cinnamic acids, which displayed slightly enhanced blood-stage activity compared to the parent drug, we have now combined this emblematic antimalarial with natural fatty acids. This affords surface-active ionic liquids whose liver-stage antiplasmodial activity is either retained or slightly enhanced, while revealing blood-stage antiplasmodial activity at least one order of magnitude higher than that of the parent compound. These findings open new perspectives towards the cost-effective recycling of classical drugs that are either shelved or in decline, and which is not limited to antimalarial agents.