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The flapping kinematics have revealed a new paradigm of locomotion which is highly maneuverable and efficient compared to traditional propulsion systems. This work numerically investigates a three-dimensional wing undergoing pitching oscillations using Large eddy simulation (LES). The wake structure is presented using the Q -function, and the influence of pitching frequency on the structure of the wake is discussed. The vortices appear to travel as interconnected vortex rings in the bifurcated wake and are completely different from the two-dimensional investigations. The increase in pitching frequency ( St D) generates the interlinking structures between the two limbs of the bifurcated wake. The interlinking between the two limbs increases with St D and will get disrupted at sufficiently high St D . The increase in St D increased the force generated by the pitching wing, and the periodic dynamics between the force coefficients slowly transformed to quasi-periodic dynamics. The transition to quasi-periodic dynamics has not reduced the force generation of the pitching wing. The disruption of interlinking structures between the two limbs enhanced the lift generated by the pitching wing. The present investigation shows that the wake vortex structure strongly depends on St D . The generation of a jet in the wake is visible in the mean velocity profile indicating the thrust developed by the wing. The formation of multiple peak profiles indicated the formation of multiple jets, which resulted in enhanced thrust production. The Reynolds stress field generated from the velocity fluctuations appears to be influenced by both the pitching oscillations and vortex interactions. This study can guide the selection of better kinematic parameters to enhance the propulsive performance. [ABSTRACT FROM AUTHOR]

Most common signs and symptoms of typhoid are localised to gastrointestinal system. Less commonly, extraintestinal infectious complications occur with enteric fever. The present case report is about a 29-year-old female, without risk factors, who presented with fever, loose stools and cough of five days duration. The patient was diagnosed to have paratyphi A bacteraemia, with clinical and radiological features of pneumonia. Her sputum cultures were sterile, and hence paratyphi A pneumonia was diagnosed. She received 14 days of antimicrobial therapy and recovered. Vi-based monovalent vaccines do not offer protection against most paratyphoid fever, because only Salmonella serovars Typhi, and paratyphi C carry the Vi antigen. Further studies are needed on bivalent and polyvalent typhoid vaccines covering all serovars. [ABSTRACT FROM AUTHOR]

Background & objectives: There are limited data from India on the post-COVID multisystem inflammatory syndrome in adults (MIS-A). The objective of the present study was to evaluate the clinical profile of patients with MIS-A admitted to a tertiary care centre in southern India. Methods: This single-centre retrospective study was conducted from November 2020 to July 2021, and included patients aged >18 yr admitted to the hospital as per the inclusion and exclusion criteria. Results: Nine patients (5 male, mean age 40±13 yr) met the criteria for MIS-A. Five patients had proven COVID-19 infection or contact history 36.8±11.8 days back. All patients were positive for SARS-CoV-2 IgG antibody, negative for COVID-19 PCR, and had negative blood, urine and sputum cultures. All patients had fever and gastrointestinal (GI) symptoms, and five patients had left ventricular dysfunction. All patients had neutrophilic leucocytosis at presentation and elevated biomarkers such as C-reactive protein serum procalcitonin, D-dimer and ferritin. The majority of the patients (7/9 i.e. 77.78%) were treated with intravenous hydrocortisone (50-100 mg q6h-q8h). Six patients recovered completely whereas three patients expired. Interpretation & conclusions: Fever and GI symptoms were the most common presentation of MIS-A. Elevated serum procalcitonin may not be useful in differentiating bacterial sepsis from MIS-A. Most patients responded to corticosteroids. [ABSTRACT FROM AUTHOR]