Intracellular delivery of nanomaterials for sub-cellular imaging and tracking of biomolecules.

Nanomaterials have many intriguing applications in biology and medicine. Unique properties such as enhanced electrical properties, increased chemical reactivity and resistance to degradation, novel optical properties and comparable size to that of biological systems have led to their use in various biomedical applications. The most important applications of nanomaterials for medicine are in drug delivery and imaging. This research focuses on utilizing the biocompatibility of single walled Carbon nanotubes (SWCNTs) and optical properties colloidal quantum dots (QDs) for cellular drug delivery and imaging of biomolecules. The first part of this research deals with single walled carbon nanotubes which are excellent candidates for targeted drug delivery applications due their unique structural and functional properties. However, prior to their use in therapeutics, their biocompatibility needs to be thoroughly investigated. The objectives of this research were to establish the biocompatibility of SWCNTs and demonstrate their use as drug delivery carriers into cells. Blood, a living tissue, is chosen as the biological system as it contains various cells which can potentially interact with SWCNTs during the delivery mechanism. The interactions of these cells in the blood (specifically white blood cells or leukocytes) with the SWCNTs provide vital information regarding the immune response of the host to the nanotubes. This research investigates the immune response of white blood cells due to SWCNTs via (a) direct interaction - presence of nanotubes in the blood and, (b) indirect interaction - presentation of nanotubes by antigen-presenting-cells to white blood cells. These two interactions recreate the innate and adaptive immune responses occurring in the body to any foreign substance. SWCNTs are functionalized with single stranded DNA (ss-DNA), which serves as a dispersant of nanotubes as well as a backbone for further attachment of other biomolecules of interest. Confocal microscopy and flow cytometric studies are performed to characterize the interactions. Results from this acute immune response study demonstrate the biocompatibility of SWCNTs in whole blood and also confirm the cellular delivery of single stranded DNA. The second part of the research is on colloidal quantum dots (QDs): nanometer sized semiconductor crystals typically between 1 run to 20 nm in diameter. In addition to being size comparable with many biological systems, and having large surface area for multiple biomolecules attachment, they possess high resistance to chemical and photo degradation, tunable emission based on size and composition which makes them excellent candidates for cellular delivery and imaging. The main objectives of this research was to demonstrate the use of QDs for cellular imaging as well as targeted biomolecule delivery by conjugating the QDs with an antibody to a functional protein and delivery into live cells. Conventional techniques deliver QDs as aggregates, however, a major challenge in the use of QDs for cellular imaging and biomolecule delivery is achieving freely dispersed QDs inside the cells. In this research, a new technique to deliver monodispersed QDs inside live cells was developed. The approach combines osmosis driven fluid transport into cells achieved by creating hypotonic environment and reversible permeabilization using low concentrations of cell permeabilization agents like Saponin. The results confirm that highly efficient endocytosis-free intracellular delivery of QDs can be accomplished using this method. Confocal microscopy is used to image the QDs inside the cells and flow cytometry is used for quantifying the fluorescence. To demonstrate targeted delivery, QDs are conjugated to the antibody of a protein: the nuclear transcriptional factor, NFkB (Nuclear Factor kappa-light chain-enhancer of activated B cells) using EDC/sulfo NHS chemistry methods. NFkB is a family of proteins with 5 different subunits and is involved in a variety of biological processes such as immune and inflammatory responses and cellular developmental processes. In unstimulated cells, NFkB is inactive in cytoplasm and translocates to the nucleus upon stimulation using bacterial products, viruses, radiation, and the like. QDs fluorescence could be used to monitor NFKB activity over extended periods of time in live cells

Structural, optical and nanomechanical properties of (1 1 1) oriented nanocrystalline ZnTe thin films

Structural, optical and nanomechanical properties of nanocrystalline Zinc Telluride (ZnTe) films of thickness upto 10 microns deposited at room temperature on borosilicate glass substrates are reported. X-ray diffraction patterns reveal that the films were preferentially oriented along the (1 1 1) direction. The maximum refractive index of the films was 2.74 at a wavelength of 2000 nm. The optical band gap showed strong thickness dependence. The average film hardness and Young’s modulus obtained from loaddisplacement curves and analyzed by Oliver-Pharr method were 4 and 70 GPa respectively. Hardness of (1 1 1) oriented ZnTe thin films exhibited almost 5 times higher value than bulk. The studies show clearly that the hardness increases with decreasing indentation size, for indents between 30 and 300 nm in depth indicating the existence of indentation size effect. The coefficient of friction for these films as obtained from the nanoscratch test was ∼0.4.Financial support in the form of fellowships to MSRNK and SK from the ACRHEM project of DRDO is acknowledged

Innovation in In-Store Promotions: Effects on Consumer Purchase Decision

With retail competition at an all-time high, today’s retailers must find new ways to attract consumers and inspire high levels of customer loyalty. Due to the scarcity of time and advancement in technological and strategical innovations, it becomes inevitable for the retailer to come up with various new ways of promoting the brands and their products in-store at the time of decision making. Innovative retail set up can create a truly differentiated in-store experience with fun, interactive tools that put a wealth of information at customers’ fingertips during the right time of purchase decision. Retailers open in-store media (ISM) and allow manufacturers to advertise to shoppers. With an informative and easy-to-use retail experience, shoppers are empowered to access a wide variety of real-time product information— including pricing, location, availability, helpful advice, targeted promotions and more — right in the aisle, without waiting for a store associate. This enhanced self-service gives customers the best of both worlds — the instant information access in an internet-based online store and the irreplaceable tactile experience of shopping in the brick and mortar store. This research paper discusses on various in-store promotional strategies, new shopping solutions and how this in turn helps the customer to make purchase decision right in the retail store. Keywords: Retail, In-store promotion, Purchase decision, Innovatio

Measurement and prediction of aerosol formation for the safe utilization of industrial fluids

Mist or aerosol explosions present a serious hazard to process industries. Heat transfer fluids are widely used in the chemical process industry, are flammable above their flash points, and can cause aerosol explosions. Though the possibility of aerosol explosions has been widely documented, knowledge about their explosive potential is limited. Studying the formation of such aerosols by emulating leaks in process equipment will help define a source term for aerosol dispersions and aid in characterizing their explosion hazards. Analysis of the problem of aerosol explosions reveals three major steps: source term calculations, dispersion modeling, and explosion analysis. The explosion analysis, consisting of ignition and combustion, is largely affected by the droplet size distribution of the dispersed aerosol. The droplet size distribution of the dispersed aerosol is a function of the droplet size distribution of the aerosol formed from the leak. Existing methods of dealing with the problem of aerosol explosions are limited to enhancing the dispersion to prevent flammable concentrations and use of explosion suppression mechanisms. Insufficient data and theory on the flammability limits of aerosols renders such method speculative at best. Preventing the formation of aerosol upon leaking will provide an inherently safer solution to the problem. The research involves the non-intrusive measurement of heat transfer fluid aerosol sprays using a Malvern Diffraction Particle Analyzer. The aerosol is generated by plain orifice atomization to simulate the formation and dispersion of heat transfer fluid aerosols through leaks in process equipment. Predictive correlations relating aerosol droplet sizes to bulk liquid pressures, temperatures, thermal and fluid properties, leak sizes, and ambient conditions are presented. These correlations will be used to predict the conditions under which leaks will result in the formation of aerosols and will ultimately help in estimating the explosion hazards of heat transfer fluid aerosols. Heat transfer fluid selection can be based on liquids that are less likely to form aerosols. Design criteria also can incorporate the data to arrive at operating conditions that are less likely to produce aerosols. The goal is to provide information that will reduce the hazards of aerosol explosions thereby improving safety in process industries

EVALUATION OF MAXIMUM ENTROPY METHOD OF SPECTRUM ESTIMATION

The parametric models autoregressive (AR)/AR-moving average (MA)/MA are sometimes not capable of finding out the power spectral densities of random sequences. Under such circumstances, the non-parametric methods outperform the parametric ones because of the sensitivity of the latter to model specifications. The maximum entropy method (MEM) is regarded as the non-parametric method of spectrum estimation; it suggests one possible way of extrapolating the autocorrelation sequence so that a more accurate estimate of the spectrum can be obtained with better resolution. This paper investigates the work of realizing MEM method and evaluating its performance with minimum variance method

Stability in Non-Normal Periodic Jacobi Operators: Advancing B\"org's Theorem

Periodic Jacobi operators naturally arise in numerous applications, forming a cornerstone in various fields. The spectral theory associated with these operators boasts an extensive body of literature. Considered as discretized counterparts of Schr\"odinger operators, widely employed in quantum mechanics, Jacobi operators play a crucial role in mathematical formulations. The classical uniqueness result by G. B\"org in $1946$ occupies a significant place in the literature of inverse spectral theory and its applications. This result is closely intertwined with M. Kac's renowned article, 'Can one hear the shape of a drum?' published in $1966$. Since $1975,$ discrete versions of B\"org's theorem have been available in the literature. In this article, we concentrate on the non-normal periodic Jacobi operator and the discrete versions of B\"org's Theorem. We extend recently obtained stability results to encompass non-normal cases. The existing stability findings establish a correlation between the oscillations of the matrix entries and the size of the spectral gap. Our result encompasses the current self-adjoint versions of B\"org's theorem, including recent quantitative variations. Here, the oscillations of the matrix entries are linked to the path-connectedness of the pseudospectrum. Additionally, we explore finite difference approximations of various linear differential equations as specific applications

A NOVEL APPROACH TO STATE SPACE TIME DOMAIN AUTOREGRESSIVE SIGNAL PROCESSING USING OPTIMAL RECURSIVE ESTIMATOR

This work describes the concept of filtering of signals using discrete Kalman filter. The true state of constant, random constant having process noise and autoregressive (p) process when corrupted by measurement noise are estimated using discrete Kalman filter and results are presented using MATLAB

Evaluation of Alcazar Scoring System to Differentiate Between Benign and Malignant Ovarian Masses- A Nepalese Perspective

Introduction: Ovarian cancer is the fifth most common cancer in Nepalese females and the tenth overall, accounting for 5% of the total new cases of cancer in females in 2020. Ultrasonography (USG) remains the primary tool for the diagnosis and characterization of ovarian masses in which many grey-scale and Doppler characteristics are evaluated. Various scoring systems have been described incorporating different USG parameters to differentiate the benign and malignant nature of ovarian masses. Alcazar scoring system includes both grey-scale as well as Doppler characteristics of the ovarian masses and is one of the more widely used systems worldwide. Methods: This was an observational cross-sectional study based on 52 consecutive patients who were clinically suspected to have ovarian mass and referred for USG evaluation and who subsequently underwent surgery.Results:As confirmed by histopathology, 37 cases were benign and 15 were malignant masses. Alcazar system of scoring identified 34 out of 37 benign cases and 15 out of 15 malignant cases with sensitivity and specificity for diagnosing malignant cases of 83.3% and 91.1% respectively. Conclusion: Alcazar system of scoring is a highly effective tool to differentiate between benign and malignant ovarian masses and can be of great help in diagnosis, characterization and effective preoperative planning

CONCRETE, REINFORCED BY CARBON FIBRE COMPOSITE STRUCTURE, LOAD BEARING CAPACITY DURING CRACKING

Different authors conducted studies on fiber reinforced concretes (FRC) with carbon fibres of different lengths and some results showed that concrete mix with homogeneously distributed short fibres in their volume have good strength and ultra-strain compared to normal plain concrete mix. However, this study is focused more on 3-dimensional (3D) carbon fibre reinforced plastic (epoxy) CFRP composite thin rods frame used as a reinforcement in concrete which shows good increase in loadbearing and ductility. Were investigated concrete mixes with superplasticizer, nano-silica, quartz sand, fine natural sand and gravels. Diagonal cross bracing carbon fibre epoxy frames were used as a reinforcement giving better ductility results. Proposed study approach is to show that the reinforced concrete with provided materials have an increased performance in terms of ductility, sustainability, and load bearing in cracked statement. Total, four groups of concrete and each group with three beams were casted and tested in this experiment, three groups with three different shapes of carbon frames and three beams without frames to compare the mechanical properties after 28 days. Failure mechanisms in any particular case were analysed.