Search results for: Nishesh Bista

Authors: Aashish Gyawali, Brinda Bhattarai, Nishesh Bista, Dr. Sundeep Rao

Abstract:

Stability, controllability, and maneuverability are critical factors for aircraft with short take-off and landing distances, such as modern fighter aircraft and UAVs. Delta wings are commonly employed in these aircraft due to their efficient aerodynamics, enabling high maneuverability and performance at both low and high speeds. Non-slender wings are used for low-speed performance and agility, while slender wings offer reduced drag and are suited for high-speed operations. In flight, an aircraft encounters different airflow patterns, including vortices that circulate from the higher-pressure lower side of the wing to the lower-pressure upper side, contributing to lift generation. However, as the angle of attack increases, the vortices can become unstable and fluctuate, resulting in induced drag. Understanding this phenomenon is crucial for developing highly stable and maneuverable aircraft. This paper focuses on studying vortex breakdown in delta wings with varying sweep angles and at different angles of attack. It aims to validate experimental and numerical solutions from previous studies on the variation of vortex breakdown in both slender and non-slender delta wings using Computational Fluid Dynamics (CFD). By examining vortex breakdown characteristics in different wing configurations, the paper aims to contribute to the development of aircraft designs that prioritize stability and maneuverability.

Keywords: CFD, delta wings, non-slender slender wings, vortices, vortex breakdown

Procedia PDF Downloads 0

Authors: Birendra Kumar Bista, Rhitik Bista, Prafulla Koirala, Lokendra Mandal, Nikrsh Raj Shrestha, Vivek Kattel

Abstract:

Introduction: Poorly controlled diabetes is associated with cause and poor outcome of stroke. High blood sugar reduces cerebral blood flow, increases intracranial pressure, cerebral edema and neuronal death, especially among patients with poorly controlled diabetes.1 SGLT2 inhibitors are associated with 50% reduction in hemorrhagic stroke compared with placebo. SGLT2 inhibitors decrease cardiovascular events via reducing glucose, blood pressure, weight, arteriosclerosis, albuminuria and reduction of atrial fibrillation.2,3 No study has been documented in low income countries to see the role of post stroke SGLT2 inhibitors on diabetic patients at and after ICU admission. Aims: The aim of the study was to measure the 12 months outcome of diabetic patients with acute stroke admitted in ICU set up with naïve SGLT2 inhibitors add on therapy. Method: It was prospective cohort study carried out in a 250 bedded tertiary neurology care hospital at the province capital Biratnagar Nepal. Diabetic patient with acute stroke admitted in ICU from 1st January 2022 to 31st December 2022 who were not under SGLT2 inhibitors were included in the study. These patients were managed as per hospital protocol. Empagliflozin was added to the alternate enrolled patients. Empagliflozin was continued at the time of discharged and during follow up unless contraindicated. These patients were followed up for 12 months. Outcome measured were mortality, morbidity requiring readmission or hospital visit other than regular follow up, SGLT2 inhibitors related adverse events, neuropsychiatry comorbidity, functional status and biochemical parameters. Ethical permission was taken from hospital administration and ethical board. Results: Among 147 diabetic cases 68 were not treated with empagliflozin whereas 67 cases were started the SGLT2 inhibitors. HbA1c level and one year mortality was significantly low among patients on empaglifozin arm. Over a period of 12 months 427 acute stroke patients were admitted in the ICU. Out of them 44% were female, 61% hypertensive, 34% diabetic, 57% dyslipidemia, 26% smoker and with median age of 45 years. Among 427 cases 4% required neurosurgical interventions and 76% had hemorrhagic CVA. The most common reason for ICU admission was GCS<8 (51%). The median ICU stay was 5 days. ICU mortality was 21% whereas 1 year mortality was 41% with most common reason being pneumonia. Empaglifozin related adverse effect was seen in 11% most commonly lower urinary tract infection in 6%. Conclusion: Empagliflozin can safely be started among acute stroke with better Hba1C control and low mortality outcome compared to treatment without SGLT2 inhibitor.

Keywords: diabetes, ICU, mortality, SGLT2 inhibitors, stroke

Procedia PDF Downloads 43