NUMERICAL INVESTIGATION OF THE INFLUENCE OF THE LINK POSITIONING IN THE CORONARY STENT INSIDE THE NORMAL ARTERY: A COMPARATIVE STUDY OF TWO COMMERCIAL STENT DESIGNS

This paper investigates the performance of two commercial stent designs inside the normal artery for induced Von Mises Stress and radial displacement pattern. Investigation focuses on identifying the key design feature of the stent structure responsible for varied stress and displacement pattern. Two commercial stent designs, Supraflex (Stent S) and Yukon Choice (Stent T),are modeled using micro CT images and MIMICS® while idealized models are used for investigation. ANSYS Workbench is used to numerically expand the stent inside an idealized normal artery with inflation pressure. The stent and the artery are modeled using elastic-plastic and hyperelastic material models, respectively. The results suggest crucial influence of the link positioning in inducing an area of higher Von Mises Stress and stress gradient. The locations of a higher stress gradient are those in line with unbound stent crowns. Also, higher and uniform arterial displacement can be observed in the locations in line with the bound crown. Results also suggested a considerable difference in arterial distortion induced by two designs, causes for which can also be attributed to the differences in the link placement. The study suggests that the link connections play a crucial role in setting up stress field/radial displacement. Suitable modification of the link positioning can reduce the higher stress gradient and arterial distortion, which probably can reduce arterial injury

EXPERIMENTAL ANALYSIS OF THE EFFECT OF THE WOVEN ARAMID FABRIC ON THE STRAIN TO FAILURE BEHAVIOR OF PLAIN WEAVED CARBON/ARAMID HYBRID LAMINATES

Remarkable advances in the research and development of micro/mini Unmanned Aerial Vehicles (UAVs) seek thin, lightweight and strong materials for their structural applications. As these structures involve various loading conditions in both the in-plane and through-the-thickness directions during their life cycle, the assurance of the structural stability in each direction is deemed mandatory. The woven Aramid fibers as high strain materials (HSM) are known to improve the through-the-thickness impact strength. However, the addition of the HSM can affect the overall tensile behavior of composite laminates. This study investigates the effect of the woven Aramid fiber on the in-plane tensile behavior of Carbon/ epoxy laminates. Laminates are fabricated using an easy and cost-effective Vacuum Assisted Resin Infusion Molding (VARIM) setup. A uniaxial tensile test was conducted to analyze the tensile behavior of Carbon/Aramid hybrid composites. The effect of adding the woven Aramid layer and the Carbon fabric sequence on the tensile modulus, strain to failure and modulus of toughness are investigated in this study. The results revealed that the presence of Aramid has a positive hybrid effect on the failure strain, exhibiting pseudo-ductile behavior with a compromise in the tensile modulus of the virgin Carbon/epoxy laminate

Evolvable Hardware Based Optimal Position Control of Quadcopter

Trading off performance metrics in control design for position tracking is unavoidable. This has severe consequences in mission-critical systems such as quadcopter applications. The controller area and propulsion energy are conflicting design parameters, whereas the reliability and tracking speed are related metrics to be optimized. In this research, a switching-based position controller was co-simulated with the quadcopter model. Performance analysis of the Field Programmable Gate Array (FPGA)-based controller validates a better scheme for tracking speed, propulsion energy, and reliability optimization under similar error performance. To improve the computation power and controller area, the dynamic partial reconfiguration(DPR) approach has been adapted and implemented on FPGA using the Vivado Integrated Development Environment (IDE), where a ranking-based approach brings into action either proportional derivative, sliding mode, or model predictive controllers for each dimension of position tracking. It is verified by analyzing the cumulative tracking speed, reliability, controller area, and propulsion energy metrics that the proposed controller can optimize all these metrics within three successive iterations of tracking either in the same direction or in any combination of directions. Concerning the implementation results of the controller with the switching-based controller, there is 6 % computation power and 30 % resource savings due to DPR

The modulatory effect of septilin on cytotoxicity of cisplatin in a human breast adenocarcinoma cell line

435-441Cisplatin (Csp) is a recurrently used chemotherapeutic drug but its use is inadequate due to undesirable adverse effects. In search of alternative medicine more attention has been given to phytochemicals. Septilin (Spt), a polyherbal drug and its therapeutic potential is huge but there is a scarcity of studies on its cytotoxic potential on cancer cells. The current study was designed to examine the effects of Spt in combination with Csp on human breast adenocarcinoma (MCF-7) and normal human breast epithelial (MCF-10A) cell lines. Cell viability for Spt treated cells was studied using MTT assay. IC50 value of Csp on MCF-7 cells was found to be 10 µg/mL at 24 h. This dose was further used to study the combined effects of Csp with Spt on MCF-7 and MCF-10A cell lines. Maximum cytotoxicity of Spt on MCF-7 cells was observed at Spt 5 µg/mL. The mechanism of Spt induced cytotoxicity was studied using apoptosis assay. Spt did not show any cytotoxic effects on MCF-10 A normal human breast epithelial cells, indicating Spt has no effect on normal cells. Our findings suggest that Spt can be used in combination with an anticancer drug Csp to increase its efficacy and/or to minimize its side effects on normal cells

Effect of V-shaped Ribs on Internal Cooling of Gas Turbine Blades

Thermal efficiency and power output of gas turbines increase with increasing turbine rotor inlet temperature. The rotor inlet temperatures in most gas turbines are far higher than the melting point of the blade material. Hence the turbine blades need to be cooled. In this work, simulations were carried out with the leading edge of gas turbine blade being internally cooled by coolant passages with V-shaped ribs at angles of 30°, 45° or 60° and at three aspect ratios (1:1, 1:2 and 2:3). The trailing edge of the blade was cooled by cylindrical and triangular pin-fin perforations in staggered and inline arrangements. Numerical analyses were carried out for each configuration of the cooling passages. The best cooling passages for leading edge and trailing edge were deduced by comparing the results of these analyses. It was found that using V-shaped ribs and fins induces a swirling flow, which in turn increases the velocity gradient and hence produces an improvement in heat transfer. The results show that under real time flow conditions, the application of V-shaped ribs and pin-fin perforations is a very promising technique for improving blade life

The modulatory effect of septilin on cytotoxicity of cisplatin in a human breast adenocarcinoma cell line

Cisplatin (Csp) is a recurrently used chemotherapeutic drug but its use is inadequate due to undesirable adverse effects. In search of alternative medicine more attention has been given to phytochemicals. Septilin (Spt), a polyherbal drug and its therapeutic potential is huge but there is a scarcity of studies on its cytotoxic potential on cancer cells. The current study was designed to examine the effects of Spt in combination with Csp on human breast adenocarcinoma (MCF-7) and normal human breast epithelial (MCF-10A) cell lines. Cell viability for Spt treated cells was studied using MTT assay. IC50 value of Csp on MCF-7 cells was found to be 10 μg/mL at 24 h. This dose was further used to study the combined effects of Csp with Spt on MCF-7 and MCF-10A cell lines. Maximum cytotoxicity of Spt on MCF-7 cells was observed at Spt 5 μg/mL. The mechanism of Spt induced cytotoxicity was studied using apoptosis assay. Spt did not show any cytotoxic effects on MCF-10 A normal human breast epithelial cells, indicating Spt has no effect on normal cells. Our findings suggest that Spt can be used in combination with an anticancer drug Csp to increase its efficacy and/or to minimize its side effects on normal cells

Review on Unconventional Wind Energy

Fossil fuel is the major source of energy and is a fast depleting resource. The phenomenal increase in fossil fuel consumption has adversely affected carbon footprint impacting our environment. With strict environmental regulations in place, the focus towards renewable sources of energy is gaining momentum supported by recent advancement in technologies in wind, hydro and solar. Wind turbines were the first forms of clean energy has seen a major increase in power production. The site restrictions, have limited the wind turbine from being used to its maximum potential. In recent years, the concept of some unconventional methods is being proposed. In this review, the various types of wind turbines are emphasized with their recent advances and depicting the challenges faced in various aspects. The reviews contain details mainly about 4 types of wind turbines i.e. floating offshore wind turbine, airborne wind turbine, highway wind turbine systems and locomotive mounted wind turbine

3rd Zonal Workshop on Fisheries and Aquaculture Policy: Responsible Fisheries and Sustainable Aquaculture Perspectives for West Coast States Goa, Gujarat, Karnataka, Kerala, Maharashtra, and Union Territories of Daman and Diu, Dadra & Nagar Haveli and Lakshadweep

3rd Zonal Workshop on Fisheries and Aquaculture Policy: Responsible Fisheries and Sustainable Aquaculture Perspectives for West Coast States Goa, Gujarat, Karnataka, Kerala, Maharashtra, and Union Territories of Daman and Diu, Dadra & Nagar Haveli and Lakshadweep 21-23 June, 200

Catch composition and discards in set bagnets of Karanja Estuary, Raigad, Maharashtra

Dol netting is one of the major fishing methods used mainly by traditional fishermen of Maharashtra. Study of catch composition of dol nets operated in Karanja Estuary of Raigad district, Maharashtra was carried out during September 2016 - May 2017. A total of ten single-day dol-netters were selected for the purpose of this study. Fortnightly on-board sampling and questionnaire-based sampling were carried out to fulfil the objectives of the study. The number of fishing days per month ranged from 12-16 due to tide-based restrictions. Dol net catch comprised 50 species of fin fishes, 3 species of elasmobranchs, 13 species of shrimps, 10 species of crabs, 5 species of cephalopods, 2 species of jellyfish, 4 species of sea snakes, 1 species of lobster and 2 species of stomatopods. Major catch composition of dol nets recorded during the study included Acetes indicus, Arius maculatus, Charybdis callianassa , Chrysaora Caliparea, Coilia dussumieri , Harpadon nehereus , Lepturacanthus savala , Miyakella nepa, Mystus gulio and Parapenaeopsis sculptilis. Significant discards such as jellyfishes, juveniles of several fishes and plastics were recorded in the dol nets operated in the Karanja estuar

Influence of fabric orientation and compression factor on the mechanical properties of 3D E-glass reinforced epoxy composites

3-D E-glass fabric reinforced epoxy composites at 6 mm thickness were fabricated for various orientations of the binder yarn viz. 0°, 30°, 45°, 60° and 90° respectively. Tensile, flexural, interlaminar shear stress tests were conducted to ascertain the influence of binder yarn orientation on the mechanical properties of the composites. The composites with 0° binder yarn orientation showed the best strength followed by 90° whilst the others showed highly depleted traits in comparison. Shear stress induced at the interface of each lamina was seen as the major reason for drop in the strength. A secondary study was carried out to explore the effect of compression factor during fabrication on the mechanical properties of the composites. Laminates with varying thickness namely, 4 mm, 5 mm and 7 mm but, with same number of plies of 3D E-glass fabric at 0° orientation were fabricated. The test results were compared with the results of 6 mm composites from the primary study. The results showed that, compression factor affected the mechanical properties of the composites and had a direct relation with increasing compression factor up to a certain value beyond which a drop in properties was seen. Composites pressed to a thickness of 5 mm showed the best properties. Drop in properties was attributed to close packing of reinforcement and crushing of fibres leading to inefficient stress transfer. Scanning electron microscopy was employed to understand the modes of failure. The major failure modes observed were delamination, matrix cracking and debonding. Based on the results obtained, these composites can be seen as a material system for applications like ballistic armours, structural renovations and automobile components