A study on vortex flow control on inlet distortion in the re-engined 727-100 center inlet duct using computational fluid dynamics

Computational fluid dynamics was used to investigate the management of inlet distortion by the introduction of discrete vorticity sources at selected locations in the inlet for the purpose of controlling secondary flow. These sources of vorticity were introduced by means of vortex generators. A series of design observations were made concerning the importance of various vortex generator design parameters in minimizing engine face circumferential distortion. The study showed that vortex strength, generator scale, and secondary flow field structure have a complicated and interrelated influence on the engine face distortion, over and above the initial geometry and arrangement of the generators. The installed vortex generator performance was found to be a function of three categories of variables: the inflow conditions, the aerodynamic characteristics associated with the inlet duct, and the design parameters related to the geometry, arrangement, and placement of the vortex generators within the outlet duct itself

UV-C irradiation is highly effective in inactivating SARS-CoV-2 replication

The potential virucidal effects of UV-C irradiation on SARS-CoV-2 were experimentally evaluated for different illumination doses and virus concentrations (1000, 5, 0.05 MOI). At a virus density comparable to that observed in SARS-CoV-2 infection, an UV-C dose of just 3.7 mJ/cm2 was sufficient to achieve a more than 3-log inactivation without any sign of viral replication. Moreover, a complete inactivation at all viral concentrations was observed with 16.9 mJ/cm2. These results could explain the epidemiological trends of COVID-19 and are important for the development of novel sterilizing methods to contain SARS-CoV-2 infection

Preliminary investigation on the presence of peptidesinhibiting the growth of Listeria innocua and Listeriamonocytogenes in Asiago d\u2019Allevo cheese

Bacteriocins produced by some strains of lactic acid bacteria or antimicrobial casein fragments can be released into the water-soluble fraction of cheeses during ripening. However, there is a lack of experimental evidence which supports the theory that these peptides can exert an effective antimicrobial effect. The aim of this study was to investigate the anti-listerial activity of such peptides in Asiago d\u2019Allevo cheese. The water-soluble fraction of Asiago was ultrafiltrated through 10 kDa cutoff membranes before being dialyzed (100\u2013500 Da cut-off) to remove proteins, salts, and organic acids, prior to freeze-drying. The growth of Listeria innocua LRGIA 01 and of Listeria monocytogenes strain 162 in Brain Heart Infusion (BHI) at 30 \ub0C in the presence or absence of 5 to 40 mg c5mL 121 of cheese water-soluble extracts (WSEs) lyophilisate was monitored spectrophotometrically. WSEs lyophilisates from cheeses of different production systems (total mixed-ration-fed cows and cheese-making in a dairy plant in May; alpine-grazing cows and cheese-making in situ in July and September) and ripened for 6, 12, and 18 months were tested. A limited dosedependent inhibition of growth was observed at all the assayed concentrations. The addition of cheese WSEs lyophilisates to BHI broth inhibited the growth of <50% of L. innocua LRGIA 01 and <10% of L. monocytogenes strain 162. Antilisterial activity was only significantly affected by ripening time (it was maximal at 6 months). Quantification of peptides with a sequence similar to the antimicrobial casein fragments \u3b1S1-CN f(1\u201323) (isracidin) and \u3b1S2-CN f(183\u2013207) in cheese WSEs suggests that their anti-listerial activity is likely also to be due to other peptides