Application of Holographic Particle Image Velocimetry in Bubbly Flow

Measuring the velocity field of a bubbly flow is of major importance in many industrial applications like, bubble column reactors. Traditional PIV setup is limited to single plane measurements. The present study involved extension of the existing holographic PIV method to two-phase flow velocimetry. The objective of the present study was to conduct velocity measurements using in-line holographic microscopy arrangement to analyze a flow consisting of an air bubble rising through stagnant water in a rectangular column. Neutrally buoyant 8 μm sized hollow glass spheres are scattered uniformly in the continuous phase and are used as seed particles for image analysis. . Double-pulsed hologram is taken with a 2K by 2K pixels CCD sensor with 200μs in between the two frames, which allows only a small movement of both the particles (in the continuous phase) and that of the dispersed phase itself. Holograms are reconstructed at different distances to produce images at every millimeter of the measurement volume. An averaging technique is developed to process the images to reduce the noise in reconstructed holographic images and make it useful for cross-correlation analysis. The image pairs are cross correlated and velocity vectors are obtained for the continuous phase. The dispersed phase velocity is measured using the shift in the center of the bubble. After analyses of all the image pairs throughout the measurement volume, a two component three dimensional velocity field is produced for the two-phase flow.Mechanical Engineerin

Synchronization of Time Delayed Systems by Common Delay Time Modulations

We investigate the synchronization phenomenon between two identical time delayed systems with the common time delay, modulated by a chaotic or random signal. The phenomenon is verified by the conditional Lyapunov exponent. The relation between the present form of synchronization with generalized one is also discussed

Charged Particle Identification Using Calorimetry and Tracking at the Belle II Experiment

Particle identification (PID) is a critical procedure carried out in high energy physics experiments in search of new physics. When particles of matter (i.e., an electron) and antimatter (i.e., a positron) collide, new types of particles may form given certain conditions. Such particles may be classified as hadrons--which feel the strong nuclear force--and leptons--which do not. Identifying particles at the Belle II experiment is done by combining the measurement of energy deposited in the calorimeter with the measurement of track momentum in the tracker. In a tau lepton ($\tau$) decay sample, particles such as electrons, muons, and pions may be separated and identified using such measurements.https://ir.library.louisville.edu/uars/1031/thumbnail.jp

A modified risk detection approach of biomarkers by frailty effect on multiple time to event data

Multiple indications of disease progression found in a cancer patient by loco-regional relapse, distant metastasis and death. Early identification of these indications is necessary to change the treatment strategy. Biomarkers play an essential role in this aspect. The survival chance of a patient is dependent on the biomarker, and the treatment strategy also differs accordingly, e.g., the survival prediction of breast cancer patients diagnosed with HER2 positive status is different from the same with HER2 negative status. This results in a different treatment strategy. So, the heterogeneity of the biomarker statuses or levels should be taken into consideration while modelling the survival outcome. This heterogeneity factor which is often unobserved, is called frailty. When multiple indications are present simultaneously, the scenario becomes more complex as only one of them can occur, which will censor the occurrence of other events. Incorporating independent frailties of each biomarker status for every cause of indications will not depict the complete picture of heterogeneity. The events indicating cancer progression are likely to be inter-related. So, the correlation should be incorporated through the frailties of different events. In our study, we considered a multiple events or risks model with a heterogeneity component. Based on the estimated variance of the frailty, the threshold levels of a biomarker are utilised as early detection tool of the disease progression or death. Additive-gamma frailty model is considered to account the correlation between different frailty components and estimation of parameters are performed using Expectation-Maximization Algorithm. With the extensive algorithm in R, we have obtained the threshold levels of activity of a biomarker in a multiple events scenario.Comment: 21 pages, 2 figures,7 table

Handling missingness value on jointly measured time-course and time-to-event data

Joint modeling technique is a recent advancement in effectively analyzing the longitudinal history of patients with the occurrence of an event of interest attached to it. This procedure is successfully implemented in biomarker studies to examine parents with the occurrence of tumor. One of the typical problem that influences the necessary inference is the presence of missing values in the longitudinal responses as well as in covariates. The occurrence of missingness is very common due to the dropout of patients from the study. This article presents an effective and detailed way to handle the missing values in the covariates and response variable. This study discusses the effect of different multiple imputation techniques on the inferences of joint modeling implemented on imputed datasets. A simulation study is carried out to replicate the complex data structures and conveniently perform our analysis to show its efficacy in terms of parameter estimation. This analysis is further illustrated with the longitudinal and survival outcomes of biomarkers' study by assessing proper codes in R programming language

Handling missingness value on jointly measured time-course and time-to-event data

Joint modeling technique is a recent advancement in effectively analyzing the longitudinal history of patients with the occurrence of an event of interest attached to it. This procedure is successfully implemented in biomarker studies to examine parents with the occurrence of tumor. One of the typical problem that influences the necessary inference is the presence of missing values in the longitudinal responses as well as in covariates. The occurrence of missingness is very common due to the dropout of patients from the study. This article presents an effective and detailed way to handle the missing values in the covariates and response variable. This study discusses the effect of different multiple imputation techniques on the inferences of joint modeling implemented on imputed datasets. A simulation study is carried out to replicate the complex data structures and conveniently perform our analysis to show its efficacy in terms of parameter estimation. This analysis is further illustrated with the longitudinal and survival outcomes of biomarkers' study by assessing proper codes in R programming language

BRUCELLAR UVEITIS IN EASTERN INDIA

Objective: Brucellosis- one of the major zoonotic diseases, still remains an uncontrolled problem, in regions of high endemicity. Ophthalmic brucellosis is not studied and overlooked in most developing countries.  Considering the severe outcome of undiagnosed ophthalmic brucellosis, in this paper we made attempts to find out whether this disease still remains a health problem in a South East Asian developing country, where study of this disease is largely neglected.  Methods This study was carried out over a one year period from January 2015 to December 2015. Blood samples were collected from clinically confirmed cases of uveitis and they were subjected to five serological and one genus specific molecular investigations, for the detection of Brucella infection.Results Out of 20 uveitis cases, 4 (20%) cases confirmed as brucellar uveitis, by serological tests followed by PCR confirmation. After treatment of brucellosis all the four patients were recovered uneventfully.Conclusion: Brucella infection involving the eye is still a significant problem in South East Asian countries; hence in all uveitis cases in this reason brucellosis should be excluded by available laboratory tests.Government of India (Dept. of Biotechnology the major zoonotic diseases, still remains an uncontrolled problem, in regions of high endemicity. Ophthalmic brucellosis is not studied and overlooked in most developing countries.  Considering the severe outcome of undiagnosed ophthalmic brucellosis, in this paper we made attempts to find out whether this disease still remains a health problem in a South East Asian developing country, where study of this disease is largely neglected.   Methods This study was carried out over a one year period from January 2015 to December 2015. Blood samples were collected from clinically confirmed cases of uveitis and they were subjected to five serological and one genus specific molecular investigations, for the detection of Brucella infection.Results Out of 20 uveitis cases, 4 (20%) cases confirmed as brucellar uveitis, by serological tests followed by PCR confirmation. After treatment of brucellosis all the four patients were recovered uneventfully.Conclusion: Brucella infection involving the eye is still a significant problem in South East Asian countries; hence in all uveitis cases in this reason brucellosis should be excluded by available laboratory tests

Interaction of DNA-lesions induced by sodium fluoride and radiation and its influence in apoptotic induction in cancer cell lines

AbstractFluoride is an essential trace element but also an environmental contaminant with major sources of exposure being drinking water, food and pesticides. Previous studies showed that sodium fluoride (NaF) at 5mM or more is required to induce apoptosis and chromosome aberrations and proposed that DNA damage and apoptosis play an important role in toxicity of excessive fluoride. The aim of this study is directed to understand the nature of DNA-lesions induced by NaF by allowing its interaction with radiation induced DNA-lesions. NaF 5mM was used after observing inability to induce DNA damages and apoptosis by single exposure with 50μM or 1mM NaF. Co-exposure to NaF and radiation significantly increased the frequency of aberrant metaphases and exchange aberrations in human lymphocytes and arrested the cells in G1 stage instead of apoptotic death. Flow cytometric analysis, DNA fragmentation and PARP-cleavage analysis clearly indicated that 5mM NaF together with radiation (1Gy) induced apoptosis in both U87 and K562 cells due to down regulation of expression of anti-apoptotic proteins, like Bcl2 in U87 and inhibitors of apoptotic proteins like survivin and cIAP in K562 cells. This study herein suggested that single exposure with extremely low concentration of NaF unable to induce DNA lesions whereas higher concentration induced DNA lesions interact with the radiation-induced DNA lesions. Both are probably repaired rapidly thus showed increased interactive effect. Coexposure to NaF and radiation induces more apoptosis in cancer cell lines which could be due to increased exchange aberrations through lesions interaction and downregulating anti-apoptotic genes