The Role of Proteome in Cellular Zn2+ Trafficking and in the Ability of the Fluorescent Zinc Sensors to Image Intracellular Zn2+

Zinc is an essential biological trace metal used in as many as 3000 Zn-proteins, about 10% of the eukaryotic proteome, as either a structural constituent or a catalytic cofactor. These proteins include the zinc fingers, the most prevalent transcription factors that bind a wide range of gene promoters and thus regulate gene expression. A eukaryotic cell contains several hundred micromolar of Zn2+- almost all of it is bound to specific Zn-proteins. Recently, Zn2+ has been reported to serve as a regulatory signal and a neurotransmitter, suggesting that there also exists a dynamic Zn2+ pool in cells. These findings led to the synthesis of a wide range of fluorescent sensors to image intracellular mobile Zn2+. Despite extensive knowledge about thousands of Zn-proteins, the Zn2+ trafficking pathway from its entry into the cytosol by transporters to the formation of Zn-proteins is not well understood. This present work has studied the role of proteome in cellular Zn2+ trafficking using fluorescent zinc sensors, including FluoZin-3, Zinquin (ZQ), TSQ, Newport Green (NPG) and Zinpyr-1 (ZP1). The titration of proteome pre-treated with FluoZin-3, a relatively high affinity Zn2+ sensor with the stability constant of 15 nM, with Zn2+ has revealed that proteome contains a significant number of high affinity, non-specific Zn2+ binding sites, with the stability constants on the order of 10-10 M. The discovery of these high affinity binding sites of proteome suggested that along with Zn-metallothionein, proteome too can serve as a possible intermediate along the way to the formation of native Zn-proteins. Moreover, this finding raises the question how the majority of the fluorescent zinc sensors with the stability constants ranging from micromolar to nanomolar image intracellular labile Zn2+ by circumventing the proteome’s high zinc buffering capacity. Interestingly, the thiol binding reagents, N-ethylmaleimide (NEM) and DTNB abolished these high affinity sites, revealing the involvement of proteomic sulfhydryl groups in these Zn2+ binding sites. The loss of proteome’s zinc buffering capacity upon sulfhydryl modification can explain how the sensors bind the dynamic Zn2+ pool by surpassing the proteome’s high Zn2+ binding affinity. For example, Zinquin, a high affinity sensor with Kd of 2 nM, could bind the mobile Zn2+ only when the proteome was significantly modified by the reaction under investigation, such as the liberation of proteomic Zn2+ by nitric oxide, which reacts with the sulfhydryl groups and thus reduces proteome’s buffering capacity. In case of unperturbed proteome, these sensors either are unable to compete for mobile Zn2+ with proteome’s high affinity Zn2+ binding sites or generate ternary adduct, Proteome•Zn-Sensor, with Zn2+ preferentially bound to proteome. Newport Green, for example, with its modest stability constant (Kd 10-5 – 10-6 M) cannot efficiently compete with proteomic ligands to image mobile Zn2+. It could not bind intracellular Zn2+ shuttled into LLC-PK1 cells using the ionophore, pyrithione. Moreover, when proteomic Zn2+ was liberated by the reaction with sulfhydryl binding reagents, NEM and diethylamine NONOate (DEA-NO), in the presence of Newport Green, insignificant amount of Zn-NPG was detected. By contrast, the higher affinity Zn2+ sensor (Kd 0.7 nM) than Newport Green, ZP1 formed ternary adduct Proteome•Zn-ZP1 with the dynamic Zn2+, where Zn2+ is adventitiously bound to proteome’s high affinity zinc binding sites. Besides with the mobile Zn2+, ZP1 also seems to react with the static distribution of cellular Zn2+ in specific Zn-proteins and generates ZP1-Zn-Proteome ternary adduct. Therefore, the effectiveness of the sensors to bind the cellular dynamic Zn2+ is a variable of proteome’s Zn2+ binding characteristics

Synthesis and Characterizations of Poly(3-hexylthiophene) and Modified Carbon Nanotube Composites

Poly(3-hexylthiophene) and modified (functionalized and silanized) multiwall carbon nanotube (MWNT) nanocomposites have been prepared through in situ polymerization process in chloroform medium with FeCl3 oxidant at room temperature. The composites are characterized through Fourier transfer infrared spectroscopy (FT-IR), Raman, and X-ray diffraction (XRD) measurements to probe the nature of interaction between the moieties. Optical properties of the composites are measured from ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy. Conductivity of the composites is followed by four probe techniques to understand the conduction mechanism. The change (if any) in C=C symmetric and antisymmetric stretching frequencies in FT-IR, the shift in G band frequencies in Raman, any alterations in λmax of UV-Vis, and PL spectroscopic measurements are monitored with modified MWNT loading in the polymer matrix

INFLUENCE OF ABSURD THEATRICAL TRADITION IN MODERN ASSAMESE DRAMA: A COMPARATIVE STUDY WITH REFERENCE TO THE PLAYS OF ARUN SHARMA

The contemporary Assamese plays have developed as a result of numerous interwoven influences and channels. And it is clear that western influences were what shaped the Assamese plays into their perfection. After independence, Assamese writers of prose, poetry, and theatre, produced works that were on pace with the period. It demonstrated identical compositional experimentation and sociological analysis. The Assamese plays exhibit a strong western heritage from playwrights like Ibsen, Shaw, Beckett, and other absurd dramatists. A few dramatists, like Dr. Arun Sarma, Ratna Ojha, and Himendrakumar Borthakur made reflections of works of Lonesco and Beckett and despite the fact the impact of absurd dramas was not very common. In this article, the researcher investigated the works of the most renowned and esteemed Assamese playwright, Dr. Arun Sarma (1964), to emphasize the distinguishing components and similarities of Shri Nibaran Bhattacharya and Aahaar with those of absurd dramatic tropes. The researcher discovered, using the comparative technique of analysis, that, despite frequent assertions to the contrary, Aahaar has much in common with the absurdist movement, whereas Shri Nibaran Bhattacharya cannot be regarded as a fully-fledged absurd drama

An Analytical Approximation for the Excess Noise Factor of Avalanche Photodiodes with Dead Space

Approximate analytical expressions are derived for the mean gain and the excess noise factor of avalanche photodiodes including the effect of dead space. The analysis is based on undertaking a characteristic-equation approach to obtain an approximate analytical solution to the existing system of recurrence equations which characterize the statistics of the random multiplication gain. The analytical expressions for the excess noise factor and the mean gain are shown to be in good agreement with the exact results obtained from numerical solutions of the recurrence equations for values of the dead space reaching up to 20% of the width of the multiplication region

Implementation Challenges of ICT in the Public Sector in Upazila Region of Bangladesh: An Empirical Study

Information and Communication Technology (ICT) plays a pivotal role in achieving Digital Bangladesh's vision of making the government accountable, transparent and effective in providing services to the citizens. The ICT-based governance (e-governance) in service delivery mechanism has become essential and time worthy. However, the implementation of e-governance is not up to the mark and the government is not getting the full benefits of e-governance due to the structural, organizational, and behavioral barriers. The dilemma between the service providers (agent) with numerous problems and the recipients’ viewpoints (principal) has been analyzed how the problem lies and the principal faces problem to get services. The objective of this study is to analyze the current situation of ICT-enabled Public Service Delivery; implementation challenges of ICT at the Upazila level of Bangladesh and come up with an evidence-based solution.  To achieve the objectives, both qualitative and quantitative approaches were employed. Purposive random sampling was used to collect data through offline and online questionnaire surveys. Besides, interview and observation methods were also employed for strengthening the study findings. The study found that strong policy supports of the government i.e. ICT policy, and digital Bangladesh vision enable the e-government services to benefit the citizen. However, it is evident that the dearth of IT physical infrastructure, unstable internet connection, shortage of skilled manpower, and technology fear of public employees create obstacles to provide ITC-enabled services. Sometimes people’s unawareness also serves as barrier to receive e-government services. The study recommends improvement of internet speed, supply of continuous electricity supply, training of public employees, providing upgraded technology, and developing user-friendly softwares to address those problems and enhance ICT-induced public service delivery system.  Keywords: E-governance, Readiness, Public Service Delivery, Barriers, Way forwar

Efficacy and Concerns of Technical Project in Bangladesh: An Assessment of the Managing at the Top 2 (MATT2) Project

Least-Developed Countries (LDCs) and developing countries receive various supports for their development and technical projects from developed nations and development partners. Bangladesh is no exception. Managing at the Top 2 (MATT2) is a technical development project that was designed in collaboration with the governments of the UK and Bangladesh and carried out in Bangladesh with funding of the UK. The primary aim of the project was to provide practical training for approximately 2000 top-level officials of the Bangladesh Civil Service to enhance their efficiency in developing and implementing innovative projects to deliver public services. In this paper, the purpose, process and results of the project are analyzed using a qualitative approach to understand the benefits and barriers of the project. It was found that MATT2 produced remarkable success, with 305 performance improvement projects (PIPs) were developed and implemented by the participating bureaucrats. Government employees were benefitted from practical knowledge on project preparation, skill development and the citizens were benefited from the outputs. Although the project claims 100% success in terms of implementation, projects were influenced by some bottlenecks that include unsuitability of PIPs, lower reform value, monetary motivation and selection of project area out of the participants’ jurisdiction.  The authors suggest considering the intended and unintended consequences of the MATT2 to undertaking similar projects in the future. Keywords: Bangladesh; Civil servants; Development; Experiential learning; PIPs; Skill developmen

Alternative institutional arrangements for contract farming in poultry production in Bangladesh and their impacts on equity

Also available in the ILRI Repository on Livestock Research at http://hdl.handle.net/10568/217Livestock Production/Industries,

Identifying and Prioritizing the Performance Criteria of Denim Washing Industry in Bangladesh Using Analytic Hierarchy Process

In the midst of the negative growth of textile and RMG industries, the mother industry of Bangladesh, the denim industry, has been doing its part incessantly. While the prospect of the denim industry looks promising from the last few years, the factors that drive this industry forward remain unanswered. Among the process chain of denim manufacturing, most value addition occurs in denim washing. This paper focuses on identifying and prioritizing the performance criteria of the denim washing sector in particular. In this context, export-oriented denim washing factories are chosen and the identified criteria are evaluated by using Analytical Hierarchy Process (AHP). This study is qualitative in nature and the secondary data about the factors were collected initially through review of previous literature, magazines, books, and newspapers. A structured questionnaire was developed to collect data from 35 factories. The results of the study show that cost, time, quality, and flexibility are the critical factors for success. The findings also seem to be consistent in general in regard to the test results, and it provides insight for improvement in the denim washing industry of Bangladesh

Locating target at high speed using image decimation decomposition processing

We develop a decimation-decomposition processing technique that consists of judiciously selecting certain decimation-decomposed components of an image and then performing inter-component processing. For a (kx,ky)-decimation decomposition, there may be up to kxky decimation-decomposed components. The minimal surviving and maximal non-surviving lengths associated with inter-component processing algorithm allows for clutter suppression. By removing detection redundancies, one can locate the target at high speed. A “where-then-what” model is proposed for target tracking and recognition. It locates the target by-image decimation-decomposition processing first and then recognizes the target in question using a suitable image recognition technique