Description:
Measurement of apoptotic markers in tumors can be directly correlated with the cell cycle phase using flow cytometry (FCM). The conventional DNA content analysis requires cell permeabilization to stain nuclei with fluorescent probes such as propidium iodide or use of a costly UV-excitation line for Hoechst 33342 probe. The access to FCM is also still limited to centralized core facilities due to its inherent high costs and complex operation. This work describes development and proof-of-concept validation of a portable and user-friendly microfluidic flow cytometer (μFCM) that can perform multivariate real time analysis on live cells using sampling volumes as small as 10 microliters. The μFCM system employs disposable microfluidic cartridges fabricated using injection molding in poly(methylmethacrylate) transparent thermoplastic. Furthermore, the dedicated and miniaturized electronic hardware interface enables up to six parameter detection using a combination of spatially separated solid-state 473 (10 mW) and 640 nm (20 mW) lasers and x-y stage for rapid laser alignment adjustment. We provide new evidence that a simple 2D flow focusing on a chip is sufficient to measure cellular DNA content in live tumor cells using a far-red DNA probe DRAQ5. The feasibility of using the μFCM system for a dose-response profiling of investigational anti-cancer agents on human hematopoietic cancer cells is also demonstrated. The data show that μFCM can provide a viable novel alternative to conventional FCM for multiparameter detection of caspase activation and dissipation of mitochondrial inner membrane potential (ΔΨm) in relation to DNA content (cell cycle phase) in live tumor cells.
Description:
Measurement of apoptotic markers in tumors can be directly correlated with the cell cycle phase using flow cytometry (FCM). The conventional DNA content analysis requires cell permeabilization to stain nuclei with fluorescent probes such as propidium iodide or use of a costly UV-excitation line for Hoechst 33342 probe. The access to FCM is also still limited to centralized core facilities due to its inherent high costs and complex operation. This work describes development and proof-of-concept validation of a portable and user-friendly microfluidic flow cytometer (
Description:
We investigate the comparative performance of state-owned commercial banks (SOCBs) and private commercial banks (PCBs) of Bangladesh with respect to efficiency and profitability in financing international trade. Taking a ten-year panel data over 2003-2012 of all four SOCBs and four categorised PCBs, we apply the non-parametric approach data envelopment analysis (DEA) to measure and compare efficiency of the banks using output-oriented Malmquist Productivity Indices (MPI). Furthermore, we develop some specialised profitability ratios on trade financing business of the banks to measure profitability. Our results suggest that PCBs are more efficient and profitable compared to SOCBs' although PCBs provide less trade financing than SOCBs'. The study recommends SOCBs to progress technologically for sustaining themselves in the competitive banking sector of Bangladesh. Moreover, we identify the sources of profitability that would explain the banks' strategic position in trade financing business which would motivate more banks to support international traders through trade financing.
Description:
The six cities air pollution is used to estimate and investigate the marginal curve of a function describing lung growth for set of children in a longitudinal study. This article proposes penalized regression spline technqiue based ona semiparametric mixed models (MM) framework for an additive model. This smoothing approach fits marginal models for longitudinal unbalanced measurements by using a Bayesian inference approach, implemented using a Markov chain Monte Carlo approach with the Gibbs sampler. The unbalanced case in which missing or different number of measurements for a set of subjects is more practical and common in real life studies. This methodology makes it possible to establish a straightforward approach to similar models using R programming, when it is not possible to do so using existing codes.
Description:
Obstacles present in the line of sight transmission path of a wireless signal severely attenuates the received signal power. Extreme fluctuations of the received signal power caused by shadowing can create "blind spots". Blind spots are areas within the cellular coverage area from where no communication is possible to the base station (BS). For single path packet based services link failures results in total loss of communication. The problem of link failure and blind spots can almost be eliminated in the recently proposed multipath cellular architecture (MCA) which provisions up to three different communication links from the mobile node (MN) to three adjacent BSs through overlapped coverage. Voice and/or multimedia packet delivery can thus benefit by establishing communication from the best interface in terms of received signal power. In this paper, we evaluate the performance of the multi-path MCA model in reducing link failure and blind spot communication problems in presence of multiple obstacles and shadow fading. Obstacle mobility model is utilized as the preferred user mobility model. Video transmission performance improves significantly in terms of reduced packet loss and improved reproduced signal quality at the receiver for the multipath MCA model compared to the existing single path cellular network architecture