Model and Performance Analysis of Piezoelectric Energy Harvester System for Different Harvester Beam Configurations

Electricity is one of the main energy resources will be used to operate many devices and appliance for making human life as comfortable. In many of the applications the small electronics equipments or devices are used which requires power in milli Watts, micro Watts, nano Watts. This small power requirement devices are gets power form battery which is nowadays replaced by the PEH energy technology. There are many configurations are used and modeled to improve the power performance of the PEH. This paper is focus on the improvements of the PEH through the continuous beam, segmented beam with tip mass and clamped – clamped continuous beam harvester. The performances of the harvesters are analyzed with the factor like voltage generation, power generation, strain stress imposed on the harvester like that. The major difficulty in the use of PEH harvester to obtain electrical energy from the vibrations or motion energy is that the output power is very less; efficiency is very poor during the low frequency periods. The vibration frequency is not at all same for all duration of vibration. So, the vibrations in the frequency reduce the output of PEH particularly at low frequency situations. So, finding and designing a suitable PEH to produce high output power in any field of vibration energy source available

Ethnobotanical Studies from Amaravathy Range of Indira Gandhi Wildlife Sanctuary, Western Ghats, Coimbatore District, Southern India

The ethnobotanical studies were carried out in the Amaravathy Range of India Gandhi Wildlife Sanctuary, Anamalais, the Western. Ghats, Tamilnadu during June 2005 – May 2006. Puliyars and Muthuvars are the two dominant tribes who inhabit the dense jungles of this range; they have a fair knowledge on the indigenous flora. Due to intensive and extensive explorations have resulted in the collection of information on ninety four plant species; out of which, 73 are wild and the rest are cultivated; within the wild plants 24 are used as edible fruits; 12 species as a leafy vegetable; 23 species are having medicinal value and 18 species utilized for miscellaneous uses and the same is provided

The bountiful and baffling baculovirus: the story of polyhedrin transcription

Baculoviruses are a unique group of eukaryotic viruses that parasitize insects. The prototype member of the family Baculoviridae is Autographa californica multiple nuclear polyhedrosis virus (AcMNPV). Global interest in baculovirus biology stems from two important uses of baculoviruses - as biopesticides and as a highly favoured eukaryotic expression system for the large-scale production of recombinant proteins in the laboratory. Of late, baculoviruses have invited renewed interest by virtue of their potential use as a delivery system in gene therapy. Although the baculovirus expression vector system (BEVS) is extensively used worldwide, the transcriptional regulation of the hyperactive promoters used to drive foreign gene expression still remains shrouded in mystery. It is clear, however, that this regulation involves an intricate interplay of both host and viral factors. This review provides an overview of what we do know about the mechanisms of transcription of baculoviral genes, with special emphasis on the polyhedrin promoter, the workhorse promoter of the BEVS, and the insect cell host factors involved in enhancing transcription from it

All-Trans Retinoic Acid Directs Urothelial Specification of Murine Embryonic Stem Cells via GATA4/6 Signaling Mechanisms

The urinary bladder and associated tract are lined by the urothelium, a transitional epithelium that acts as a specialized permeability barrier that protects the underlying tissue from urine via expression of a highly specific group of proteins known as the uroplakins (UP). To date, our understanding of the developmental processes responsible for urothelial differentiation has been hampered due to the lack of suitable models. In this study, we describe a novel in vitro cell culture system for derivation of urothelial cells from murine embryonic stem cells (ESCs) following cultivation on collagen matrices in the presence all trans retinoic acid (RA). Upon stimulation with micromolar concentrations of RA, ESCs significantly downregulated the pluripotency factor OCT-4 but markedly upregulated UP1A, UP1B, UP2, UP3A, and UP3B mRNA levels in comparison to naïve ESCs and spontaneously differentiating controls. Pan-UP protein expression was associated with both p63- and cytokeratin 20-positive cells in discrete aggregating populations of ESCs following 9 and 14 days of RA stimulation. Analysis of endodermal transcription factors such as GATA4 and GATA6 revealed significant upregulation and nuclear enrichment in RA-treated UP2-GFP+ populations. GATA4−/− and GATA6−/− transgenic ESC lines revealed substantial attenuation of RA-mediated UP expression in comparison to wild type controls. In addition, EMSA analysis revealed that RA treatment induced formation of transcriptional complexes containing GATA4/6 on both UP1B and UP2 promoter fragments containing putative GATA factor binding sites. Collectively, these data suggest that RA mediates ESC specification toward a urothelial lineage via GATA4/6–dependent processes

Novel Sp family-like transcription factors are present in adult insect cells and are involved in transcription from the polyhedrin gene initiator promoter

We earlier documented the involvement of a cellular factor, polyhedrin (polh) promoter-binding protein, in transcription from the Autographa californica nuclear polyhedrosis virus polh gene promoter. Sequences upstream of the polh promoter were found to influence polh promoter-driven transcription. Analysis of one such region, which could partially compensate for the mutated polh promoter and also activate transcription from the wild-type promoter, revealed a sequence (AcSp) containing a CACCC motif and a loose GC box resembling the binding motifs of the transcription factor Sp1. AcSp and the consensus Sp1 sequence (cSp) specifically bound factor(s) in HeLa and Spodoptera frugiperda(Sƒ9) insect cell nuclear extracts to generate identical binding patterns, indicating the similar nature of the factor(s) interacting with these sequences. The AcSp and cSp oligonucleotides enhanced in vivo expression of a polh promoter-driven luciferase gene. In vivo mopping of these factor(s) significantly reduced transcription from the polh promoter. Recombinant viruses carrying deletions in the upstream AcSp sequence confirmed the requirement of these factor(s) in polh promoter-driven transcription in the viral context. We demonstrate for the first time DNA-protein interactions involving novel members of the Sp family of proteins in adult insect cells and their involvement in transcription from the polh promoter

JunB Mediates Basal- and TGFβ1-Induced Smooth Muscle Cell Contractility

Smooth muscle contraction is a dynamic process driven by acto-myosin interactions that are controlled by multiple regulatory proteins. Our studies have shown that members of the AP-1 transcription factor family control discrete behaviors of smooth muscle cells (SMC) such as growth, migration and fibrosis. However, the role of AP-1 in regulation of smooth muscle contractility is incompletely understood. In this study we show that the AP-1 family member JunB regulates contractility in visceral SMC by altering actin polymerization and myosin light chain phosphorylation. JunB levels are robustly upregulated downstream of transforming growth factor beta-1 (TGFβ1), a known inducer of SMC contractility. RNAi-mediated silencing of JunB in primary human bladder SMC (pBSMC) inhibited cell contractility under both basal and TGFβ1-stimulated conditions, as determined using gel contraction and traction force microscopy assays. JunB knockdown did not alter expression of the contractile proteins α-SMA, calponin or SM22α. However, JunB silencing decreased levels of Rho kinase (ROCK) and myosin light chain (MLC20). Moreover, JunB silencing attenuated phosphorylation of the MLC20 regulatory phosphatase subunit MYPT1 and the actin severing protein cofilin. Consistent with these changes, cells in which JunB was knocked down showed a reduction in the F:G actin ratio in response to TGFβ1. Together these findings demonstrate a novel function for JunB in regulating visceral smooth muscle cell contractility through effects on both myosin and the actin cytoskeleton

The impact of discrete modes of spinal cord injury on bladder muscle contractility

Background: Prior studies have compared the effect of spinal cord injury elicited using distinct approaches on motor and visceral function. However, the impact of such discrete modes of injury specifically on bladder muscle contractility has not been explored in detail. The goal of this study is to compare the impact of complete spinal cord transection versus clip compression at thoracic vertebra eight (T8) on bladder muscle contractility. Methods: Rats underwent no treatment (Control), laminectomy (Sham, SH); complete extradural transection (TX); or cord compression with an aneurysm clip (CX). Bladders and spinal cords were harvested at 6 wk for contractility studies or histological analysis. Results: Detrusor strips from TX and CX rats showed higher spontaneous activity than those from SH rats. Furthermore, the duration of the neurally-mediated contractile response was longer in TX and CX rats compared to controls and showed attenuated relaxation. No significant differences were observed between muscle strips from SH, TX or CX rats in response to KCl, ATP or phenylephrine. However, tissues from TX and CX rats showed a higher sensitivity to carbachol compared to that from SH animals. Conclusions: Complete SCI in rats either by cord transection or compression elicits qualitatively similar changes in bladder muscle contractility. Whereas cord transection is arguably easier to perform experimentally, cord compression better models the situation observed clinically, such that each approach has clear advantages and limitations

Fluidization and Resolidification of the Human Bladder Smooth Muscle Cell in Response to Transient Stretch

Background: Cells resident in certain hollow organs are subjected routinely to large transient stretches, including every adherent cell resident in lungs, heart, great vessels, gut, and bladder. We have shown recently that in response to a transient stretch the adherent eukaryotic cell promptly fluidizes and then gradually resolidifies, but mechanism is not yet understood. Principal Findings: In the isolated human bladder smooth muscle cell, here we applied a 10% transient stretch while measuring cell traction forces, elastic modulus, F-actin imaging and the F-actin/G-actin ratio. Immediately after a transient stretch, F-actin levels and cell stiffness were lower by about 50%, and traction forces were lower by about 70%, both indicative of prompt fluidization. Within 5min, F-actin levels recovered completely, cell stiffness recovered by about 90%, and traction forces recovered by about 60%, all indicative of resolidification. The extent of the fluidization response was uninfluenced by a variety of signaling inhibitors, and, surprisingly, was localized to the unstretch phase of the stretch-unstretch maneuver in a manner suggestive of cytoskeletal catch bonds. When we applied an “unstretch-restretch” (transient compression), rather than a “stretch-unstretch” (transient stretch), the cell did not fluidize and the actin network did not depolymerize. Conclusions: Taken together, these results implicate extremely rapid actin disassembly in the fluidization response, and slow actin reassembly in the resolidification response. In the bladder smooth muscle cell, the fluidization response to transient stretch occurs not through signaling pathways, but rather through release of increased tensile forces that drive acute disassociation of actin