Control of rotorcraft retreating blade stall using air-jet vortex generators

A series of low-speed wind tunnel tests were carried out on an oscillating airfoil fitted with two rows of air-jet vortex generators (AJVGs). The airfoil used had an RAE 9645 section and the two spanwise arrays of AJVGs were located at x/c=0.12 and 0.62. The devices and their distribution were chosen to assess their ability to modify/control dynamic stall; the goal being to enhance the aerodynamic performance of helicopter rotors on the retreating blade side of the disc. The model was pitched about the quarter chord with a reduced frequency (k) of 0.1 in a sinusoidal motion defined by a=15o+10sin_ t. The measured data indicate that, for continuous blowing from the front row of AJVGs with a momentum blowing coefficient (C μ) greater than 0.008, modifications to the stalling process are encouraging. In particular, the pitching moment behavior exhibits delayed stall and there is a marked reduction in the normal force hysteresis

Pancreatic hyperamylasemia during acute gastroenteritis: incidence and clinical relevance

BACKGROUND: Many case reports of acute pancreatitis have been reported but, up to now, pancreatic abnormalities during acute gastroenteritis have not been studied prospectively. OBJECTIVES: To evaluate the incidence and the clinical significance of hyperamylasemia in 507 consecutive adult patients with acute gastroenteritis. METHODS: The clinical significance of hyperamylasemia, related predisposing factors and severity of gastroenteritis were assessed. RESULTS: Hyperamylasemia was detected in 10.2 % of patients studied. Although amylasemia was found over four times the normal values in three cases, the clinical features of acute pancreatitis were recorded in only one case (0.1%). Hyperamylasemia was more likely (17%) where a microorganism could be identified in the stools (p < 0.01). Among patients with positive stool samples, Salmonella spp. and in particular S. enteritidis, was the microorganism most frequently associated with hyperamylasemia [17/84 (20.2 %) and 10/45 (22.2%), respectively], followed by Rotavirus, Clostridium difficile and Campylobacter spp. Patients with hyperamylasemia had more severe gastroenteritis with an increased incidence of fever (80 % vs 50.6 %, O.R. 3.0; P < 0.01), dehydration (18% vs 8.5%; O.R. 2.5; P < 0.05), and a higher mean number of evacuations per day (9.2 vs 7.5; P < 0.05) than those with amylasemia in the normal range. Hyperamylasemia was significantly associated with cholelithiasis, (30.0 % vs 10.7%, O.R. 3.5; P < 0.01) and chronic gastritis or duodenal ulceration (22.0 % vs 10.2%, O.R. 2.4, P < 0.05). CONCLUSIONS: Hyperamylasemia is relatively frequent, and is associated with severe gastroenteritis. However, acute pancreatitis in the setting of acute gastroenteritis, is a rare event

Antimicrobial Properties of Ethylene Vinyl Alcohol/Epsilon-Polylysine Films and Their Application in Surimi Preservation

[EN] Polymer films based on ethylene vinyl copolymers (EVOH) containing a 29 % (EVOH 29) and a 44 % molar percentage of ethylene (EVOH 44), and incorporating epsilon-polylysine (EPL) at 0 %, 1 %, 5 % and 10 % were successfully made by casting. The optical properties and the amount of EPL released from the films to phosphate buffer at pH 7.5 were evaluated, films showing great transparency and those of EVOH 29 copolymer releasing a greater amount of EPL. The antimicrobial properties of the resulting films were tested in vitro against different foodborne microorganisms and in vivo in surimi sticks. With regard to the antimicrobial capacity tested in vitro in liquid medium at 37 A degrees C and 4 A degrees C against Listeria monocytogenes and Escherichia coli over a period of 72 h, films showed a considerable growth inhibitory effect against both pathogens, more notably against L. monocytogenes, and being EVOH 29 more effective than EVOH 44 films. At 37 A degrees C, total growth inhibition was observed for EVOH 29 films incorporating 10 % EPL against both microorganisms whereas the copolymer EVOH 44 did show total inhibition against L. monocytogenes and the growth of E. coli was reduced by 6.64 log units. At 4 A degrees C, no film was able to inhibit completely bacterial growth. Scanning electron microscopy micrographs showed corrugated cell surfaces with blisters and bubbles, and collapse of the cells appearing shorter and more compact after treatment with EPL. Finally, the films were successfully used to increase the shelf life of surimi sticks. The results show the films developed have a great potential for active food packaging applications.The authors acknowledge the financial support of the Spanish Ministry of Economy and Competitiveness, projects AGL2012-39920-C03-01, and fellowship funding for V. M.-G.Muriel-Galet, V.; Lopez-Carballo, G.; Gavara Clemente, R.; Hernández-Muñoz, P. (2014). 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A Staphylococcus xylosus isolate with a new mecC allotype

Recently, a novel variant of mecA known as mecC (mecA(LGA251)) was identified in Staphylococcus aureus isolates from both humans and animals. In this study, we identified a Staphylococcus xylosus isolate that harbors a new allotype of the mecC gene, mecC1. Whole-genome sequencing revealed that mecC1 forms part of a class E mec complex (mecI-mecR1-mecC1-blaZ) located at the orfX locus as part of a likely staphylococcal cassette chromosome mec element (SCCmec) remnant, which also contains a number of other genes present on the type XI SCCmec

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2–4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease