ROLE OF SELF HELP GROUPS (SHGS) IN THE PURSUIT OF EMPOWERING RURAL WOMEN: AN EMPIRICAL STUDY FROM VILLAGE CHOWGACHA, GAIGHATA, NORTH 24 PARGANAS, WEST BENGAL

The present study attempts to analyze the role of self-help groups (SHGs) to empower the rural women under National Rural Livelihood Mission (NRLM) with a case study. For this purpose, members of different SHGs as well the organizers have been interrogated with specific question schedules at the study area. It has been observed that after joining in SHG under the microcredit programme of NRLM, important changes have been brought in women’s life regarding of social mobility, awareness and skill development. But economic decision-making power in respect to the use of loan, use of income from loan, utilization and repayment of the loan is not pleasing at the household level

Phenomenon of multiple reentrant localization in a double-stranded helix with transverse electric field

The present work explores the potential for observing multiple reentrant localization behavior in a double-stranded helical (DSH) system, extending beyond the conventional nearest-neighbor hopping interaction. The DSH system is considered to have hopping dimerization in each strand, while also being subjected to a transverse electric field. The inclusion of an electric field serves the dual purpose of inducing quasiperiodic disorder and strand-wise staggered site energies. Two reentrant localization regions are identified: one exhibiting true extended behavior in the thermodynamic limit, while the second region shows quasi-extended characteristics with partial spreading within the helix. The DSH system exhibits three distinct single-particle mobility edges linked to localization transitions present in the system. The analysis in this study involves examining various parameters such as the single-particle energy spectrum, inverse participation ratio, local probability amplitude, and more. Our proposal, combining achievable hopping dimerization and induced correlated disorder, presents a unique opportunity to study phenomenon of reentrant localization, generating significant research interest.Comment: 7 pages, 6 figures, comments are Welcom

Design of a Low Voltage RF MEMS Capacitive Switch with Low Spring Constant

ABSTRACT: This paper reports on the design, testing of a low-actuation voltage Microelectromechanical systems (MEMS) switch for high-frequency applications. In the case of micromachined antennas, which involve low voltage signals, RF MEMS switches with low actuation voltage are required. The actuation voltage of RF MEMS switches mainly depends on the spring constant of the switch membrane. The mechanical design of low spring-constant foldedsuspension beams is presented first, and switches using these beams are demonstrated with measured low actuation voltage. KEYWORDS: Capacitive switch, Low actuation voltage, RF MEMS, Spring constant. I.INTRODUCTION MICROMACHINING and microelectromechanical systems (MEMS) are among the most promising enabling technologies for developing low-power low-cost miniaturized RF components for high-frequency applications. Applications such as cognitive radio system, Multiple-input multiple-output (MIMO) channels and satellite communication need antenna with the reconfigurable parameters The lifetime of capacitive switches strongly depends on the applied actuation voltage for capacitance switches, they experimentally observed a lifetime improvement of a decade for every 5-7-V drop on the switch pull-in voltage In this paper, an RF MEMS capacitive switch with low spring constant operating at a low actuation voltage is presented. II.RF MEMS SWITCHES RF MEMS switches can be classified as capacitive or ohmic on the basis of circuit configuration and as series or shunt based on the nature of contact. The ohmic contact switch consists of a thin metallic strip fixed at one end, suspended over the metallic transmission line with a gap of few microns. A metallic electrode is attached between the transmissio

The Role of Intestinal Fatty Acid Binding Proteins in Protecting Cells from Fatty Acid Induced Impairment of Mitochondrial Dynamics and Apoptosis

Background/Aims: The conformation, folding and lipid binding properties of the intestinal fatty acid binding proteins (IFABP) have been extensively investigated. In contrast, the functional aspects of these proteins are not understood and matter of debates. In this study, we aim to address the deleterious effects of FA overload on cellular components, particularly mitochondria; and how IFABP helps in combating this stress by restoring the mitochondrial dynamics. Methods: In the present study the functional aspect of IFABP under conditions of lipid stress was studied by a string of extensive in-cell studies; flow cytometry by fluorescence-activated cell sorting (FACS), confocal imaging, western blotting and quantitative real time PCR. We deployed ectopic expression of IFABP in rescuing cells under the condition of lipid stress. Again in order to unveil the mechanistic insights of functional traits, we arrayed extensive computational approaches by means of studying centrality calculations along with protein-protein association and ligand induced cluster dissociation. While addressing its functional importance, we used FCS and in-silico computational analyses, to show the structural distribution and the underlying mechanism of IFABP’s action. Results: Ectopic expression of IFABP in HeLa cells has been found to rescue mitochondrial morphological dynamics and restore membrane potential, partially preventing apoptotic damage induced by the increased FAs. These findings have been further validated in the functionally relevant intestinal Caco-2 cells, where the native expression of IFABP protects mitochondrial morphology from abrogation induced by FA overload. However, this native level expression is insufficient to protect against apoptotic cell death, which is rescued, at least partially in cells overexpressing IFABP. In addition, shRNA mediated IFABP knockdown in Caco-2 cells compromises mitochondrial dynamics and switches on intrinsic apoptotic pathways under FA-induced metabolic stress. Conclusion: To summarize, the present study implicates functional significance of IFABP in controlling ligand-induced damage in mitochondrial dynamics and apoptosis

Studies of protein folding and ligand binding dynamics in vitro and in cultured cells using fluorescence correlation spe correlation spectroscopy and allied biophysical techniques

In order to function, newly synthesized protein need to fold properly. Denatured proteins, which have had essentially all of their native three-dimensional structure disrupted, can refold from their random disordered state into a well-defined unique structure, in which the biological activity is virtually completely restored. During folding, a protein needs to search different possible conformations to reach into its native functional state. A comprehensive understanding of the early stages of protein folding remains elusive to date and is a subject of extensive research efforts. The major bottlenecks to study the early events of protein folding arise from the lack of computational and experimental techniques to study the unfolded and initial intermediate states. Fluorescence correlation spectroscopy (FCS) has been emerging as an important technique with single molecule resolution to study the diffusional and conformational dynamics of the early events of protein folding. In the present work, the rat intestinal fatty acid binding protein (IFABP) has been used as a model system. IFABP is a 15 kDa predominantly β-sheet protein that belongs to the intracellular lipid binding protein (iLBP) family. Fatty acid binding proteins are transport proteins delivering fatty acids (FAs) from cellular periphery to their subcellular destinations. They have been shown to play important roles in lipid metabolism and organelle dynamics. We used a combination of fluorescence correlation spectroscopy and far-UV circular dichroism (CD) to understand how the early processes like chain collapse and secondary structure formation influence the late folding events like the stabilization of the secondary structure and aggregation. Acid-induced unfolded IFABP was found to collapse in the presence of low concentrations of added salt and aggregate at higher concentrations. The results suggested that backbone hydrogen bond formation, not only the overall hydrophobicity of IFABP, may play crucial roles in the early collapse. Next, we explored the formation of intermediate state in the process of protein folding. We unfolded the protein by lowering the pH of the solution condition and monitored the occurrence of the intermediate state at around pH 3. A combination of tryptophan fluorescence and far-UV CD were used to study the unfolding of its tertiary and secondary structures. FCS was used to delve into the molecular events occurring in concert during the unfolding process. We observed that this intermediate state is stable enough to unfold its secondary structure after the unfolding of its tertiary structure in the presence of denaturing solvent like urea. We also observed that the effect of TFE upon the intermediate state is much less than the native or completely unfolded states. We carried over our in vitro work into the cellular system relating the structure-function properties of IFABP. A cellular model for lipid toxicity was generated with increased dose of a LCFA like sodium oleate. This lipid toxicity induced cell stress caused changes in mitochondrial morphology, loss in mitochondrial membrane potential and subsequent apoptosis. With controlled expression of IFABP in the HeLa cells, the mitochondrial morphology was partially restored with protection from apoptosis. The above findings were validated in Caco-2 cells where in the cellular metabolic stress, a controlled expression of IFABP could restore mitochondrial morphology and provided protection from apoptosis. A part of the thesis work also carries the distribution of IFABP in subcellular compartments in the presence and absence of its FA ligand and its diffusion was monitored at single cell resolution under cholesterol depleted condition by using CLSM, FCS, TIRF and FACS. It was noticed that although IFABP’s localization near the plasma membrane did not reduce under membrane cholesterol depleted condition, and the protein could still bind to some integral part of the membrane while receiving and trafficking its FA ligands inside the cell. Thus it was presumed that this protein could have evolved to receive their lipid ligands from the cell plasma membrane in a membrane microdomain-independent phenomenon. This present work is just a preliminary approach in addressing this phenomenon and more work are to be done to explore the mechanism of ligand uptake at single cell resolution

Biodegradation of lactic acid and polyethylene glycol based polyester urethanes

221-228A novel polyester urethane based on lactic acid and polyethylene glycol 400 (PEG400) was synthesized. The biodegradation of the polyester urethane under soil burial condition and by cultured bacteria (Pseudomonas aeruginosa) at different temperatures (5, 15, 37ºC) was studied. The biodegradation was assessed from the weight loss, tensile strength and ultimate elongation as well as chemical changes by FTIR spectroscopy and visual changes by optical and scanning electron microscopy. After 30 days of exposure of the polyester urethane films to cultured Pseudomonas aeruginosa around 33-36% degradation in terms of weight loss was observed. Under soil burial degradation the samples have shown 62% weight loss in 180 days but there is around 98 to 99% loss in tensile strength and elongation at break