Faculty Publications
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Item Characteristics of airborne bacteria in Mumbai urban environment(Elsevier, 2014) Gangamma, S.Components of biological origin constitute small but a significant proportion of the ambient airborne particulate matter (PM). However, their diversity and role in proinflammatory responses of PM are not well understood. The present study characterizes airborne bacterial species diversity in Mumbai City and elucidates the role of bacterial endotoxin in PM induced proinflammatory response in ex vivo. Airborne bacteria and endotoxin samples were collected during April-May 2010 in Mumbai using six stage microbial impactor and biosampler. The culturable bacterial species concentration was measured and factors influencing the composition were identified by principal component analysis (PCA). The biosampler samples were used to stimulate immune cells in whole blood assay. A total of 28 species belonging to 17 genera were identified. Gram positive and spore forming groups of bacteria dominated the airborne culturable bacterial concentration. The study indicated the dominance of spore forming and human or animal flora derived pathogenic/opportunistic bacteria in the ambient air environment. Pathogenic and opportunistic species of bacteria were also present in the samples. TNF-? induction by PM was reduced (35%) by polymyxin B pretreatment and this result was corroborated with the results of blocking endotoxin receptor cluster differentiation (CD14). The study highlights the importance of airborne biological particles and suggests need of further studies on biological characterization of ambient PM. © 2014 Elsevier B.V.Item Computational fluid dynamic approach to understand the effect of increasing blockage on wall shear stress and region of rupture in arteries blocked by arthesclerotic plaque(UK Simulation Society Clifton Lane Nottingham NG11 8NS, 2016) Hegde, S.S.; Deb, A.; Nagesh, S.Computational bio-mechanics is developing rapidly as a non-invasive tool to assist the medical fraternity to help in both diagnosis and prognosis of human body related issues such as injuries, cardio-vascular dysfunction, atherosclerotic plaque etc. Any system that would help either properly diagnose such problems or assist prognosis would be a boon to the doctors and medical society in general. This project is an attempt to use numerical analysis techniques; in particular, computational fluid dynamics (CFD) to solve hemodynamics related problems. The mathematical modeling of the blood flow in arteries in the presence of successive blockages has been analyzed using CFD technique. Different cases of blockages in terms of percentages have been modeled to study the effect of blockage on wall shear stress values and also the effect of increase in Reynolds number on wall shear stress values. The concept of fluid structure interaction (FSI) has been used to study the effect of increasing von Mises stress on arteries and to determine the region of rupture in arteries. The simulation results are validated using in vivo measurement data from existing literature. © 2016, UK Simulation Society. All rights reserved.Item EFFECT of STENOSIS SEVERITY on SHEAR-INDUCED DIFFUSION of RED BLOOD CELLS in CORONARY ARTERIES(World Scientific Publishing Co. Pte Ltd wspc@wspc.com.sg, 2019) Buradi, A.; Morab, S.; Mahalingam, A.In large blood vessels, migration of red blood cells (RBCs) affects the concentration of platelets and the transport of oxygen to the arterial endothelial cells. In this work, we investigate the locations where hydrodynamic diffusion of RBCs occurs and the effects of stenosis severity on shear-induced diffusion (SID) of RBCs, concentration distribution and wall shear stress (WSS). For the first time, multiphase mixture theory approach with Phillips shear-induced diffusive flux model coupled with Quemada non-Newtonian viscosity model has been applied to numerically simulate the RBCs macroscopic behavior in four different degrees of stenosis (DOS) geometries, viz., 30%, 50%, 70% and 85%. Considering SID of RBCs, the calculated average WSS increased by 77.70% which emphasises the importance of SID in predicting hemodynamic parameters. At the stenosis throat, it was observed that 85% DOS model had the lowest concentration of RBCs near the wall and highest concentration at the center. For the stenosis models with 70% and 85% DOS, the RBC lumen wall concentration at the distal section of stenosis becomes inhomogeneous with the maximum fluctuation of 1.568%. Finally, the wall regions with low WSS and low RBC concentrations correlate well with the atherosclerosis sites observed clinically. © 2019 World Scientific Publishing Company.Item Experimental investigation on performance of disposable micropump with retrofit piezo stack actuator for biomedical application(Springer Verlag service@springer.de, 2019) Mohith, S.; Karanth P, P.N.; Kulkarni, S.M.Extensive researches are being conducted to develop miniaturized pumping systems to fulfill the need for accurate delivery of fluids at required rates, particularly in the biomedical field. This paper presents the design, fabrication, and testing of novel valveless micropump actuated through an amplified piezo actuator. The proposed model of the micropump pump has the unique feature of a disposable chamber and employs low-cost polymeric materials, conventional molding and machining operations for fabrication. The disposable part of the pump consists of a laser-cut pump chamber with nozzle/diffuser made of Polymethyl methacrylate (PMMA) and conventionally molded silicone rubber diaphragm. The retrofit part includes the amplified piezo actuator and support structures build from PMMA. Systematic characterization of the pump was carried with water and blood mimicking fluid to understand the effect of operating parameters such as driving frequency and actuation voltage on flow rate and back pressure of the micropump. Experimental results show that the proposed design was capable of pumping 3.3–3.4 ml/min of dye solution and 1.7–1.75 ml/min of blood mimicking fluid at a driving frequency of 5 Hz and actuation voltage of 150 V. The corresponding computed volume resolution/stroke of the pump was found to about 5.75 µl and 11.25 µl of blood mimicking fluid and dye solution, respectively. The proposed pump was found to work effectively against a maximum back pressure of 156 Pa with blood mimicking fluid and 250 Pa with the dye solution as the working fluid under the same operating condition of 5 Hz and 150 V. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.Item Performance analysis of valveless micropump with disposable chamber actuated through Amplified Piezo Actuator (APA) for biomedical application(Elsevier Ltd, 2020) Mohith, M.; Karanth P, N.; Kulkarni, S.M.The precise manipulation of fluid through pumping systems has been the technological challenge in microfluidic applications. The biomedical applications call for precise and accurate delivery of fluid through miniaturized pumping systems. This paper presents a novel valveless micropump for biomedical applications operated by the Amplified Piezo Actuator. Integrating the disposable chamber and reusable actuator with the proposed micropump allows the actuator to be reused and eliminates the possibility of infection or contagion. The micropump was fabricated using low-cost polymeric materials like Polymethylmethacrylate (PMMA), Silicone rubber through CNC milling, Laser Cutting, conventional moulding operation. The micropump chamber, nozzle/diffusers, and a bossed diaphragm constituted disposable part and Amplified Piezo Actuator with structural support formed the reusable part of the micropump. The bossed diaphragm of the pump chamber consists of a central cylindrical protrusion to reduce the force of adhesion on the diaphragm and transmit force required for micropump actuation. A theoretical analysis was performed to assess the effect of diaphragm thickness and the bossed region on the effective stiffness of the diaphragm, which in turn influences the deflection achieved. Besides, an analytical approach has been presented to address the effect of adhesive force on the diaphragm surface due to the residual fluid and chamber depth. The experimental characterization of the micropump was carried out to determine the optimal performance parameters with water, fluids mimicking blood plasma, and whole blood. Based on the experimental results, the pumping rate and head developed by the micropump have been significantly affected by factors such as bossed ratio, diaphragm thickness, depth of the micropump chamber, and viscosity of the fluid. The optimum configuration of the micropump cosidered silicone rubber diaphragm with thickness of 0.20 mm having a bossed ratio of 0.33 and a chamber depth of 1.25 mm. With the optimal operating parameters of 150 V sinusoidal input of frequency 5 Hz, the proposed micropump was capable of delivering 7.192 ml/min, 6.108 ml/min, and 5.013 ml/min of water and blood plasma, whole blood mimicking fluid with the maximum backpressure of 294.00 Pa, 226.243 Pa, and 204.048 Pa respectively. The corresponding resolution, i.e., pumping volume/stroke of the micropump was about 23.972 µl, 20.358 µl, and 16.708 µl, respectively. © 2020 Elsevier LtdItem Segmentation and classification of white blood cancer cells from bone marrow microscopic images using duplet-convolutional neural network design(Springer, 2023) Devi, T.G.; Patil, N.; Rai, S.; Philipose, C.P.Cancer is a disease linked to the untamed and rapid division of cells in the body. Cancer detection through conventional methods like complete blood count is a tedious and time-consuming task prone to human errors. The introduction of image processing techniques and computer-aided diagnostics is beneficial to this field as the results obtained by utilizing these methods are quick and accurate. The proposed method in this paper uses a design Convolutional Leaky RELU with CatBoost and XGBoost (CLR-CXG) to segment the images and extract the important features that help in classification. The binary classification algorithm and gradient boosting algorithm CatBoost (Categorical Boost) and XGBoost (Extreme Gradient Boost) are implemented individually. Moreover, Convolutional Leaky RELU with CatBoost (CLRC) is designed to decrease bias and provide high accuracy, while Convolutional Leaky RELU with XGBoost (CLRXG) is designed for classification or regression prediction problems which will increase the speed of executing the algorithm and improve its performance. Thus the CLR-CXG classifies the test images into Acute Lymphoblastic Leukemia (ALL) or Multiple Myeloma (MM). Finally, the CLRC algorithm achieved 100% accuracy in classifying cancer cells, and the recorded run time is 10s. Moreover, the CLRXG algorithm has gained an accuracy of 97.12% for classifying cancer cells and 12 s for executing the process. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Item Plasmonic Elliptical Nanohole Array for On-Chip Human Blood Group Detection(Institute of Electrical and Electronics Engineers Inc., 2023) Sahu, S.K.; Singh, M.A novel refractive index (RI) plasmonic biosensor with high sensitivity for human blood group detection is proposed and numerically investigated in the visible and near-infrared (NIR) regime. The proposed structure is based on a metal-insulator-metal (MIM) waveguide with an array of elliptical nanoholes. These nanoholes are used as the sensing surface and support important optical properties, such as extraordinary optical transmission (EOT) and nanoscale confinement of light. We have simulated and optimized the biosensor using RF module of COMSOL Multiphysics software, predicting the sensitivity values of three blood groups (A, O, and B) as 64.26, 101.16, and 82.1 nm/RIU, respectively. High sensitivity, precision, and portability make the reported sensor highly valuable for point-of-care applications, emergency situations, and resource-limited settings. By reducing the time for blood typing procedures and small sample volume requirements, MIM biosensor has the potential to enhance patient care and streamline medical processes. © 2023 IEEE.Item Hybrid Plasmonic Circular Aperture Waveguide for Blood Glucose Sensing(Institute of Electrical and Electronics Engineers Inc., 2024) Vankalkunti, S.; Singh, N.; Singh, M.A novel approach for blood glucose (or blood sugar) sensing utilizing a hybrid plasmonic circular aperture waveguide (HPCAW)-based nanostructure is proposed. The reported sensor combines the unique optical properties of plasmonic waveguides and circular aperture to achieve higher sensitivity and specificity in glucose detection. The HPCAW structure is designed to efficiently confine and propagate surface plasmon polaritons (SPPs) along the circular aperture, enabling enhanced light-matter interaction within the sensing region. Through rigorous numerical simulations and validation, we demonstrate the superior performance of the HPCAW sensor in terms of sensitivity (391.72 nm/RIU), figure of merit (FOM) (7.08 RIU-1), and detection accuracy (DA) (0.018 nm-1) compared to conventional glucose sensing techniques. Moreover, the proposed sensor offers inherent advantages, such as label-free detection, compact footprint, and compatibility with microfluidic systems. HPCAW provides a promising platform for the next-generation blood glucose monitoring applications with potential clinical translation. 1558-1748 © 2024 IEEE.Item Improvements in bioactivity, blood compatibility, and wear resistance of thermally sprayed carbon nanotube reinforced hydroxyapatite-based orthopedic implants(Elsevier Ltd, 2024) Shankar, D.; Jambagi, S.C.Titanium implants often fail due to aseptic loosening and non-hemocompatibility, necessitating costly revision surgeries. This study investigated the wear performance and biocompatibility of high-velocity oxy-fuel (HVOF) sprayed-hydroxyapatite (HA) and HA/alumina-19 wt%/carbon nanotube (CNT)− 1 wt% (HAC1) coatings. The novel heterocoagulation colloidal technique effectively dispersed CNTs, enhancing adhesion strength by ∼120 %, hardness by ∼45 %, and wear resistance by ∼32 % in simulated body fluid (SBF) and 17 % in dry conditions versus HA coatings, attributed to the low coefficient of friction (CoF) (1.16–1.48 times than HA) due to lubrication offered by peeled-off graphite layers from the CNT surface. Additionally, HAC1 implants exhibited superior apatite growth (∼52 % than HA), excellent non-hemolytic behavior (∼0.2 %), and no platelet activation, making it highly promising for orthopedic applications. © 2024 Elsevier LtdItem Optimization-based convolutional neural model for the classification of white blood cells(Springer Nature, 2024) Devi, T.G.; Patil, N.White blood cells (WBCs) are one of the most significant parts of the human immune system, and they play a crucial role in diagnosing the characteristics of pathologists and blood-related diseases. The characteristics of WBCs are well-defined based on the morphological behavior of their nuclei, and the number and types of WBCs can often determine the presence of diseases or illnesses. Generally, there are different types of WBCs, and the accurate classification of WBCs helps in proper diagnosis and treatment. Although various classification models were developed in the past, they face issues like less classification accuracy, high error rate, and large execution. Hence, a novel classification strategy named the African Buffalo-based Convolutional Neural Model (ABCNM) is proposed to classify the types of WBCs accurately. The proposed strategy commences with collecting WBC sample databases, which are preprocessed and trained into the system for classification. The preprocessing phase removes the noises and training flaws, which helps improve the dataset's quality and consistency. Further, feature extraction is performed to segment the WBCs, and African Buffalo fitness is updated in the classification layer for the correct classification of WBCs. The proposed framework is modeled in Python, and the experimental analysis depicts that it achieved 99.12% accuracy, 98.16% precision, 99% sensitivity, 99.04% specificity, and 99.02% f-measure. Furthermore, a comparative assessment with the existing techniques validated that the proposed strategy obtained better performances than the conventional models. © The Author(s) 2024.