526 research outputs found
Magnetophoresis and pseudo diamagnetophoresis of single particles/cells on micromagnetic patterns
No full textIn recent years, magnetophoresis has gained significant advances in precise manipulation of particles/cells for numerous applications including gene sequencing, diagnostic, single cell analysis and separation, which can be achieved using nano/micro scale magnets in microfluidic environment with the help of applied magnetic field. Generally, magetophoresis can be classified as either positive magnetophoresis or negative magnetophoresis depending on the magnetizable property of particles/cells and the surrounding medium. Here, in positive magnetophoresis, the individual magnetic particles are manipulated on the micro-magnetic patterns and in the negative magnetophoresis, the individual non-magnetic particles/cells are manipulated on the magnetic micro-cavity pattern by applying an external magnetic field. The design and fabrication of magnetic and magnetic micro-cavity patterns for logical manipulation of particles/cells are presented.
When the magnetic particles are manipulated under an applied in-plane rotating magnetic fields on the micromagnetic pattern, the behavior of particles on streptavidin/Teflon interface between the colloids and the micromagnet arrays were obtained using the magnetic forces at the phase-locked angles.
Further, the fabrication of on-chip micro-magnets using Ni80Fe20 and Co70Fe30 materials were presented to understand the mobility of superparamagnetic (SPM) particles. The maximum velocity of the particles around the periphery of the micromagnets is determined by the critical frequency, which indicates that the particle enters the phase-slipping regime from the phase-locked regime. The maximum velocity of NiFe micromagnets is approximately 3 times larger than that of CoFe micromagnets measured at the low field regions. Moreover, the maximum velocity of the particles is decreasing with increasing the thickness of Teflon coating on the micromagnets, which is in a good agreement with the variation of the magnetostatic potential energy evaluated numerically from micromagnetic simulations.
Micromagnetic simulations were performed using Mumax3 and Matlab software to calculate the magnetic domains of the patterned micromagnets, local magnetic hysteresis loops on the patterned magnetic surface, magnetic force and potential energies of the particles to understand their transport mechanism on the micromagnetic pathways.
When the non-magnetic particles are manipulated under applied strong magnetic fields on the magnetic micro-cavity pattern, a novel Pseudo diamagnetophoresis concept is introduced in place of negative magnetophoresis. The motion of label free cells are shown by introducing ferrofluids in this concept. Specifically, we develop herein a new approach to obtain independent control and directional manipulation of PsD particles, and label-free cells without needs to know the biomarkers. The logic manipulation is based on geometrical parameters of the magnetic micro-cavity patterns, the size difference of particles/cells, which is conducted in a custom-made biocompatible ferrofluid that retains the viability of cells during experiments. The magnetic micro-cavity tracks can actively switch the particles/cells at the junction which resembles an electrical diode, navigating to different directions and desired locations. The switching efficiency of particles/cells is characterized with various eclipse ratios and at various gaps between the horizontal and vertical patterns of the magnetic micro-cavity junctions. The suitable particle/cell sizes and the geometrical parameters of the magnetic micro-cavity junctions are studied to achieve successful logic manipulation of single particles/cells. This unique approach opens a door for development of label-free cells manipulation with high throughput, efficiency and reliability.prohibitionAbstract………………………………………………………………………………….…. i
Acknowledgments…………………………………………………………………………. iv
Table of Contents………………………………………………….………………………. vi
List of Figures……………………………………………………………….……………… X
Ⅰ. Introduction…………………………………………………………………………1
1.1 Positive magnetophoresis…………………………………………..……………………1
1.1.1 Magnetic manipulation of SPM particles/labeled cells on micro-magnetic patterns………………………………………………..………..……………….6
1.2 Negative magnetophoresis…………………………………………………..…12
1.2.1 Methods of manipulation of PsD particles/label free cells………………………12
1.3 Pseudo diamagnetophoresis: Manipulation of PsD particles/cells on magnetic micro-cavity patterns…………………………………………………………………………….................17
1.4 Thesis objectives and outline……………………………………………………………18
Ⅱ. Experimental methods…………………………………………….…………20
2.1 Materials……………………………………….……………………………..…..….…20
2.2 Micro-magnetic and magnetic micro-cavity pattern fabrication process……………..……………………………………………………………………….21
2.2.1 Photolithography…………………………………………………………………21
2.2.2 Lift-off method……………………………………………………………………23
2.3 Characterization techniques…………………………………………………………….23
2.3.1 Vibrating Sample Magnetometer…………………………………………………23
2.3.2 Scanning Electron Microscope……………………………………………………23
2.3.3 Transmission Electron Microscope………………………………………………..24
2.3.4 Atomic Force Microscope…………………………………………………………25
2.4 Experimental device set-up……………………………………………………………….26
2.4.1 Low magnetic field device………………………………………………………….26
2.4.2 High magnetic field device…………………………………………………………27
2.5 Data Analysis……………………………………………………………………………..27
2.6 Micromagnetic simulations ………………………………………………………………28
Ⅲ. Magnetically driven SPM particles on micro-magnetic disk pattern uisng positive magnetophoresis………………………………………...28
3.1 Manipulation of SPM partilces around full disk micro-magnetic pattern…………………28
3.2 Magnetization properties of SPM particles and magnetic thin filMaster…………………..…31
3.3 Magnetic 3D potential energy landscapes on micro-magnetic disk pattern coated with varied Teflon thickness…………………………………………………………………………...33
3.4 Velocities of SPM particles on varied Teflon thickness………………….……………..34
3.5 Velocities of SPM particles on varied magnetic thin filMaster………………………………36
3.6 Conclusion…………………………………………………………………………….…38
Ⅳ. Magnetically driven PsD particles/cells on magnetic micro-cavity patterns using Pseudo diamagnetophoresis……………………...39
4.1 Introduction……………………………..……………………………….……………….39
4.2 Magnetic force acting on PsD particles/cells suspended in ferrofluids…………………..41
4.3 Water based ferrofluids…………………………………………………………………...42
4.4 Magnetic flux distribution of PsD particle/cell and ferrofluid with varied magnetic susceptibilities under applied fields……………………………………………………………….…43
4.5 Manipulation of PsD particles around full disk magnetic micro-cavity pattern…………45
4.6 Magnetic field strength dependence of PsD particle on varied ferrofluid susceptibilities on magnetic micro-cavity disk pattern………………………………………………………….48
4.7 Independent control and directional manipulation of PsD cancer cell on magnetic micro-cavity disk pattern……………………………………………………………………………..50
4.8 Independent control and directional manipulation of PsD particles on asymmetric magnetic micro-cavity patterns………………………………………………………………………..51
4.9 Local control and switching of PsD particles on magnetic micro-cavity eclipse diode…54
5.0 Separation and local storage of PsD particles and label free cells in apartments………...60
Ⅴ. Simultaneous manipulation and separation of SPM and PsD particles by combining positive magnetophoresis and pseudo diamagnetophoresis……………………………………………………………………………62
5.1 SPM and PsD particles magnetic potential energy locations of magnetic and magnetic micro-cavity patterns…………………………………………………………………………62
5.2 Simultaneous manipulation and separation of SPM and PSD particles on magnetic patterns………………………………………………………………………………………………65
5.3 Conclusion…………………………………………………………………………….…68
References………………………………………………………………………………...…70
Summary and Outlook……………………………………………………………………79
Achievements……………………………………………………………………..………..87
List of conferences attended………………………………………………………………88
List of summer schools attended…………………………………………………………89
Project management…………………………………………..……………………………90
List of Publications………………………………………..………………………………91
List of Patents………………………………………………………………………………92DOCTORdCollectio
Mycobacterium aviumsubsp.paratuberculosisas a trigger of type-1 diabetes: destination Sardinia, or beyond?
No full textType 1 diabetes mellitus (T1DM) is a multifactorial autoimmune disease in which the insulin producing beta cell population is destroyed by the infiltrated T lymphocytes. Even though the exact cause of T1DM is yet to be ascertained, varying degree of genetic susceptibility and environmental factors have been linked to the disease progress and outcome.Mycobacterium aviumsubsp.paratuberculosis(MAP) is an obligate zoonotic pathogen that causes chronic infection of intestines in ruminants, the Johne's disease. MAP that can even survive pasteurization and chlorination has also been implicated to cause similar type of enteritis in humans called Crohn's disease. With the increasing recognition of the link between MAP and Crohn's disease, it has been postulated that MAP is an occult antigen which besides Crohn's could as well be thought to trigger T1DM. Epitope homologies between mycobacterial proteins (Hsp 65) and pancreatic glutamic acid decarboxylase (GAD 65) and infant nutrition studies implicate MAP as one of the triggers for T1DM. PCR and ELISA analyses in diabetic patients from Sardinia suggest that MAP acts as a possible trigger for T1DM. Systematic mechanistic insights are needed to prove this link. Unfortunately, no easy animal model(s) or in-vitro systems are available to decipher the complex immunological network that is triggered in MAP infection leading to T1DM
A Heart Disease Prediction Model using Logistic Regression By Cleveland DataBase
No full textThe early prognosis of cardiovascular diseases can aid in making decisions to lifestyle changes in high risk patients and in turn reduce their complications. Research has attempted to pinpoint the most influential factors of heart disease as well as accurately predict the overall risk using homogenous data mining techniques. Recent research has delved into amalgamating these techniques using approaches such as hybrid data mining algorithms. This paper proposes a rule based model to compare the accuracies of applying rules to the individual results of logistic regression on the Cleveland Heart Disease Database in order to present an accurate model of predicting heart disease. K. Sandhya Rani | M. Sai Chaitanya | G. Sai Kiran "A Heart Disease Prediction Model using Logistic Regression By Cleveland DataBase" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-3 , April 2018, URL: https://www.ijtsrd.com/papers/ijtsrd11402.pd
Design and Development of COX-II Inhibitors: Current Scenario and Future Perspective
No full textFunding Information: Sandhya Chahal would like to thank CCS HAU for financial assistance in the form of a University Research Scholarship. Payal Rani and Kiran would like to thank UGC for financial assistance in the form of a Senior Research Fellowship. Gaurav Joshi would like to thank Department of Biotechnology, New Delhi, India (Grant No. BT/PR47642/CMD/150/24/2023) for work in the area of COX inhibitors development. Publisher Copyright: © 2023 The Authors. Published by American Chemical Society.Innate inflammation beyond a threshold is a significant problem involved in cardiovascular diseases, cancer, and many other chronic conditions. Cyclooxygenase (COX) enzymes are key inflammatory markers as they catalyze prostaglandins production and are crucial for inflammation processes. While COX-I is constitutively expressed and is generally involved in “housekeeping” roles, the expression of the COX-II isoform is induced by the stimulation of different inflammatory cytokines and also promotes the further generation of pro-inflammatory cytokines and chemokines, which affect the prognosis of various diseases. Hence, COX-II is considered an important therapeutic target for drug development against inflammation-related illnesses. Several selective COX-II inhibitors with safe gastric safety profiles features that do not cause gastrointestinal complications associated with classic anti-inflammatory drugs have been developed. Nevertheless, there is mounting evidence of cardiovascular side effects from COX-II inhibitors that resulted in the withdrawal of market-approved anti-COX-II drugs. This necessitates the development of COX-II inhibitors that not only exhibit inhibit potency but also are free of side effects. Probing the scaffold diversity of known inhibitors is vital to achieving this goal. A systematic review and discussion on the scaffold diversity of COX inhibitors are still limited. To address this gap, herein we present an overview of chemical structures and inhibitory activity of different scaffolds of known COX-II inhibitors. The insights from this article could be helpful in seeding the development of next-generation COX-II inhibitors.Peer reviewe
Characterization of Superparamagnetic Particles Mobility by On-Chip Micromagnets
No full textWe fabricate on-chip micromagnets using Ni80Fe20 and Co70Fe30 materials for the characterization of mobility of superparamagnetic particles. The maximum velocity of the particles around the periphery of the micromagnets is determined by the critical frequency, which indicates that the particle enters the phase-slipping regime from the phase-locked regime. The maximum velocity of NiFe micromagnets is approximately 3 times larger than that of CoFe micromagnets measured at the low field regions. Moreover, the maximum velocity of the particles is decreasing with increasing the thickness of Teflon coating on the micromagnets, which is in a good agreement with the variation of the magnetostatic potential energy evaluated numerically from micromagnetic simulations. © 2018 IEEE.1
Performance Evaluation of Life Insurance Corporation of India
No full textHuman life is a full of risk. The effective solution of reducing the burden of these risks / losses is insurance. Insurance occupies an important position in the financial sector of an economy. In a period of less than half a century the insurance sector in a country has come in a full circle from being an open competitive market to compete nationalisation and then back to a liberalised market. The entry of private player’s in the Indian insurance market has change the nature of competition. But LIC (Life Insurance Corporation of India) continuous to be the dominant life insurer even in the liberalised scenario of Indian insurance and it moving fact on a new growth trajectory
surpassing its own past records. Insurance Regulatory and Development Authority (IRDA) has been established to protect the interests of holders of insurance policy and to regulate, promote and insure growth of the insurance industry. The present research work is an attempt to study the performance of LIC after liberalization policy regime. The aim of this study is to evaluate the financial & business performance of LIC for ten years from 1996-97 to 2005-06. This study has been divided into five chapters. The first chapter is introductory in nature and explains overview of the insurance sector. The second chapter focuses on the research methodology of the study. The third chapter evaluates the financial performance of LIC. The fourth chapter analyses the business performance of LIC. While sixth chapter shows summary, findings, conclusions and suggestions for present research study
Isolation and Identification of Crude Triacontanol from Rice Bran Wax
No full textIn present investigation crude triacontanol was isolated and identified from rice bran wax. Triacontanol was isolated by saponification and extraction method. The obtained mixture is crude Triacontanol. It was analyzed by Gas Chromatography (GC) and melting point method. Purity of triacontanol was 13.33%. 1Department of Botany, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad (M.S.), India; 2Department of Botany, University of Pune, Pune (M.S.), India* Corresponding Author, Email: [email protected] Cite This Article As: Sandhya Jaybhay, Pankaj Chate and Avinash Ade. 2010. Isolation and Identification of Crude Triacontanol from Rice Bran Wax. J. Exp. Sci. 1(2): 26
Studies on Processing and Preservation of Value Added Prodcuts from Black Grapes (Vitis Vinefera L).
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Effect of Processing on Quality and Stability of Trans and Trans Free Fat
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Identification of Staphylococcus Species by using Species Specific Primers.
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
- …
