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This comparative study was conducted from April 2018 for a period of 1 ½ years at ESIC MEDICAL COLLEGE & PGIMSR, K.K.NAGAR, CHENNAI -78 for a total of 50 patients who were diagnosed with Great saphenous varicose veins with perforator incompetence .Patients underwent open subfascial perforator ligation or subfascial endoscopic perforator ligation. The observation and inference is noted in this presentation.

This experimental analysis encapsulates the influence of Reynolds number (Re), diameter of nozzle, height to diameter (H/D) ratio and position of nozzle such as in-line and staggered over the responses heat transfer coefficient, temperature and Nusselt number of a hot flat plate exposed to cooling by multi-jet air impingement. For this analysis, a 15 x 10 cm flat plate is being heated using a heating coil having a heat flux of 7666.67 W/m2 which is maintained as constant through entire experiment. An H/D ratio of 2D, 4D and 6D is considered along with pipe diameters of 4, 6 and 8 mm and Reynolds number are changed between 18000 to 22000. Experimental design was performed with response surface methodology based central composite design. For all output responses, a quadratic model is chosen for analysis and a second order mathematical model is evolved for predicting with a higher R2 value. Desirability analysis is performed for multi-objective optimization and the optimum input parameters obtained are Reynolds no. of 20347, pipe diameter of 8 mm, H/D ratio of 2 and in-line nozzle position with the maximum heat transfer coefficient of 189.411 W/m2 K, Nusselt number of 28.8712 and minimum temperature of 56.983°C. Optimum condition-based confirmation experiments result in enhanced Nusselt number and heat transfer coefficient.

This comparative study was conducted at ESIC MEDICAL COLLEGE & PGIMSR, K.K.NAGAR,CHENNAI -78 for a total of 50 patients who were diagnosed with Great saphenous varicose veins with perforator incompetence for a period of 18 months from April 2018. Patients underwent open subfascial perforator ligation or subfascial endoscopic perforator ligation in a 1: 1 ratio by alternate allocation method. Odd numbered patients were treated by subfascial endoscopic perforator surgery and even numbered patients were treated by open subfascial perforator ligation . The observation and inference is noted in this presentation.

Reduced graphene oxide wrapped copper oxide (rGO-CuO) thin films were prepared by room temperature chemical oxidation of copper substrates and subsequent dip-coating technique. The structural, morphological and chemical analysis of the as-prepared thin films were performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDAX), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The XRD and Raman studies revealed phase pure and high crystalline nature of the thin films. The XPS analysis confirmed the presence of rGO in the rGO-CuO thin films. The influence of alkaline conditions on the morphology of the thin films was investigated. The optical properties of pure CuO and rGO-CuO thin films were evaluated. Factors responsible for the observed high solar selectivity of the rGO-CuO thin films are discussed.

Cis-regulatory elements (CREs), or enhancers, are segments of noncoding DNA that regulate the spatial and temporal expression of nearby genes. Sometimes, genes are expressed in more than one tissue, and this can be driven by two main types of CREs: tissue-specific "modular" CREs, where different CREs drive expression of the gene in the different tissues, or by "pleiotropic" CREs, where the same CRE drives expression in the different tissues. In this perspective, we will discuss some of the ways (i) modular and pleiotropic CREs might originate; (ii) propose that modular CREs might derive from pleiotropic CREs via a process of duplication, degeneration, and complementation (the CRE-DDC model); and (iii) propose that hotspot loci of evolution are associated with the origin of modular CREs belonging to any gene in a regulatory network.

The bio-efficacy of five botanicals and eleven insecticides were evaluated against jasmine blossom midge, Contarinia maculipennis Felt infesting Jasminum sambac. Among the botanicals, pungam oil was the most effective treatment with least infestation followed by NSKE were able to reduce the infestation by 82.66 and 76.21 per cent, respectively. Flubendiamide 39.35 SC was the best treatment recording the greatest reduction of 85.47 per cent followed by chlorantraniliprole 18.5 SC, respectively. The results concluded that insecticides are more effective then botanic insecticides against blossom midge.

Method of deposition of Electro-catalyst plays a significant role in the sensing behavior of electrochemical sensors for hydrogen. Amperometric hydrogen sensor operating in fuel cell mode with Nafion as proton conducting electrolyte, platinum as sensing and counter electrodes has been developed. A comparative study of response behavior of hydrogen sensors with brush coated, electrodeposited and pulsed electrodeposited Pt on gas diffusion electrode (GDE) was undertaken in the concentration range of 0–4 % H2/Ar. The crystal structure and microstructure of Pt/GDE were characterized by gracing incidence X-ray diffraction and field emission scanning electron microscopy. In-situ electrochemical impedance spectroscopy was carried out for the sensors with H2/Ar at sensing electrode side. The investigations revealed that Pt/GDE fabricated by pulsed electro-deposition has better sensitivity, response time and stability compared to the brush-coated and electrodeposited Pt/GDE sensors. Improved response of sensor with Pt/GDE fabricated by pulsed electro-deposition is explained based on microstructure of Pt electro-catalyst and interfacial characteristics of electrodes with Nafion.

Copper oxide (CuO) nanostructures, such as nanoshuttles, nanodisks and nanoparticles are synthesized by simple hydrothermal and wet chemical methods. The CuO nanostructures are prepared by thermal dehydration of Cu(OH)2·H2O crystal hydrate without any additives. The CuO nanostructures are characterized by energy dispersive X-ray absorption spectroscopy (EDAS), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, UV-vis spectroscopy and X-ray diffraction (XRD) techniques. The SEM images show that diameter of CuO nanoshuttles ranges from 300–400 nm and length of ∼1 μm. The platelet-like porous CuO nanoparticles have thickness of 0.2–0.4 μm and width of 0.5–1.5 μm. The CuO nanodisks have diameter of 500–700 nm and thickness of 60–120 nm. The EDAS analysis confirms purity of CuO samples. The FTIR spectra of CuO nanostructures exhibit that the vibration peaks correspond to stretching vibrations of Cu O bond.

Ti-5Al-2.5Sn alloy is widely used in aerospace applications due to its high specific strength, low coefficient of thermal expansion and good corrosion resistance. Presence of interstitial elements in the alloy has some significant effects on its properties. However the high notch toughness and cryogenic ductility attracts the usage of Ti-5Al-2.5Sn for usage at cryogenic temperatures even at 20K. For hydrogen embrittlement studies and for investigating notch sensitivity of Ti-5Al-2.5Sn alloy, the notched and smooth specimens from ELI grade of Ti-5Al-2.5Sn alloy were subjected to LH2exposure and tensile test at 20K (-253°C) and at 77K (-196°C). The tensile properties obtained from different specimens were compared and analyzed. Also the notch to smooth tensile strength ratio (NSR) were compared and analysed. The obtained NSR was above unity which confirms the low notch brittleness. The tensile strength values between LH2exposed and unexposed specimen at 20K and 77K were compared and it revealed greater compatibility of Ti-5Al-2.5Sn-ELI with liquid hydrogen environment.

The present work deals with the generation of H2 through water splitting using titania (TiO2) nanotubes (NTs) prepared via rapid breakdown anodization. The anatase TiO2 NTs sensitized with Pt, Pd a...

The present work aims to prepare an Al 2 O 3 /Fe-Al-Si Tritium Permeation Barrier (TPB) on Reduced Activation Ferritic-Martensitic Steel (RAFMS) an ideal material for Test Blanket Module (TBM) by employing Hot Dip Aluminizing (HDA), annealing and oxidation processes. Hydrogen adsorption/desorption behavior of barrier was tested using electrochemical and thermal spectrometry techniques for qualitative determination of H 2 permeation resistance of barrier coating. The results confirmed a five-time increase in permeation resistance of RAFMS with coating compared to uncoated RAFMS. Three different HDA melts with varying Si concentration of 1%, 6%, and 11% were used for understanding the impact of Si concentration in the Al melt and the superheat of the Al melt on the microstructure, hardness, adhesion strength, permeation and corrosion resistance of the HDA and the oxidized HDA coatings.

This is a presentation of four rare and interesting cases of bilateral breast cancer. The cases vary from Synchronous double primary carcinoma breast, bilateral infiltrating ductal carcinoma, bilateral synchronous metastatic carcinoma and metachronous breast carcinoma. The incidence of developing either primary or metastatic carcinoma in the other breast is increased in patients who already have carcinoma in one side and mammography contributes greatly to the detection of these lesions. (1) It is of significant prognostic value and important in deciding the clinical management based on the classification whether it is a primary or a secondary lesion.

Domination is an important theoretic concept in graph theory. Various types of domination have been studied By [J, K] - Set domination, A subset D ⊆ V in a graph G = (V, E) is a [J, K] - Set if every Vertex ν ∈ V − D, J ⩽ |N(ν) ∩ D| ⩽ K for non negative integers J and K, that is every vertex ν ∈ V − D is adjacent to at least J but not more than K Vertices in D. The domination number of G is denoted by γ[ J,K ](G), which is the minimum cardinality of a dominating set G. In tis paper the [J, K] - domination number of some special graphs and its application ave been studied.

The Prototype Fast Breeder Reactor (PFBR) is nearing completion at Kalpakkam, India. Sodium is the heat transfer medium for PFBR, and austenitic steel SS 316LN is the material of construction for the sodium circuits of the reactor. During reactor service, the inner surfaces of the sodium circuit pipelines undergo corrosion by interacting with liquid sodium, forming ferritic layers. Radioactive nuclides formed by the activation of corrosion products are deposited on the ferritic surface, resulting in a radioactive burden on maintenance personnel. Chemical decontamination is generally carried out by dissolving the surface ferritic layer on the inside surface of the sodium circuit. In this context, a study of the dissolution behavior of the ferritic layer on SS 316LN samples formed by exposure to liquid sodium at 823 K was carried out by monitoring the H2 released during the chemical interaction with decontamination formulation. The decontamination chemical formulation was a mixture of sulfuric acid and phos...

Method of deposition of electrocatalysts plays a vital role in controlling the particle size and in turn decides the catalytic activity of electrocatalysts in various applications. The present study is on preparing the PtxPdy alloys on gas diffusion layer (GDL) by pulsed electrodeposition method. The prepared electrodes are used as sensing electrodes in amperometric H2 sensor. This sensor operates in two electrode mode similar to proton exchange membrane fuel cell and uses Nafion as proton conducting electrolyte. Sensing electrodes with three different compositions of PtxPdy alloys were developed. Field emission scanning electron microscopy studies of PtxPdy alloys showed uniform distribution with spherical morphology. Energy dispersive X-ray mapping of alloy confirmed the uniform distribution of Pt and Pd in PtxPdy. The formation of alloy was proved by grazing incidence X-ray diffraction and high resolution transmission electron microscopy. Compositions of three different PtxPdy alloys were investigated by energy dispersive X-ray analysis and inductively coupled plasma mass spectrometry. Electrochemical active surface area of PtxPdy alloys was measured by carrying out cyclic voltammetry. Sensors with PtxPdy alloy based diffusion electrodes were assembled and tested. All PtxPdy alloys based sensors showed a linear variation with percentage concentrations of H2 (1–5%). Sensor having diffusion electrode with PtxPdy alloy of composition Pt54Pd46 in two electrode mode gave better response behaviour for H2 in Ar compared to pristine Pt.

In a scientific enquiry it is common to study the behaviour of combined systems after studying the systems individually. The graphical structures are combined in many ways. The Cartesian product is one of the way of combining graphs to get more general structures from the simple structures. In this paper, we study a–domination number of the Cartesian product of some simple path semigraphs.

The influence of the major process parameters for anodizing AA7075 is investigated to obtain an anodized layer with minimum porosity with approximately 15μm thickness. Anodization was carried out in a sulphuric acid bath with well-defined process parameters and the anodized layer thickness & Inter pore distance were measured for the chosen process parameter combinations. Porosity index was calculated and an optimized parameter combination was obtained. Voltage was found out to be most influencing parameter in the determination of porosity and thickness. In addition to this, surface finish of the non-anodized and anodized specimens was also compared. It was found out that surface finish of the specimen decreased after anodization. A statistical data model was prepared for thickness and porosity using the data obtained from experiments.

Ti-6Al-4V alloy is widely used in Aerospace applications owing to its high specific strength, low coefficient of thermal expansion and good corrosion resistance. Presence of interstitial elements in the alloy has some significant effects on its properties. However the poor notch toughness and cryogenic ductility restricts the usage of Ti-6Al-4V for temperatures lower than 77 K (-196 °C). The Extra Lower Interstitial grade alloy was developed in order to improve the notch toughness and cryogenic ductility of the Ti-6Al-4V alloy. In this refined grade, the interstitials, Oxygen and Carbon are controlled to a maximum limit of 0.12% and 0.08% respectively as compared to a maximum of 0.2% and 0.1% of standard Ti-6Al-4V alloy. In this study, the ELI grade of Ti-6Al-4V rods from three different manufacturing sources were subjected to tensile test at liquid hydrogen temperature at 20 K (-253 oC). The tensile properties obtained are compared and analyzed. The obtained ductility at 20 K is observed to have close relation with the chemical composition and interstitial content and compared with the Ti5Al2.5Sn-ELI which is ideally suitable for low temperatures upto 20 K, owing to its single phase HCP structure. A correlation has been made between the ductile properties and microstructure. By close control of chemical composition and mechanical working, Ti6Al4V-ELI can be used for temperatures lower than 77 K (-196 oC), which is otherwise is forbidden. This paper details the test data obtained from three different compositions of Ti6Al4V-ELI at 20 K, which enables the usage of this material for temperatures lower than 77 K (-196 °C) upto 20 K.

Nontraumatic subarachnoid hemorrhage (SAH) in a dialysis patient is an uncommon occurrence and is often associated with high mortality. We report for the first time in India, a case of spontaneous nontraumatic, nonaneurysmal SAH without any cerebrovascular malformation in a maintenance hemodialysis patient, following a session of hemodialysis. The dialysis prescription needs to be modified in these patients, in order to prevent worsening of cerebral edema and progression of hemorrhage. Where available, continuous forms of renal replacement therapies, with regional anticoagulation seem to be the best option for such patients, till neurologic stabilization is achieved.

Direct electrochemical reduction of UO2 to U metal is being attempted in molten salts. In this context, a new technique for the estimation of uranium metal has been developed. In this technique, the concentration of H2 released during the reaction of a metal with HBr is measured online as a function of time using an in-house developed proton exchange membrane hydrogen sensor. The method was developed by reacting different known masses of Zn with HBr and measuring the quantity of liberated hydrogen. Subsequently the methodology was employed for the estimation of U. From the calibration plots of number of moles of hydrogen released versus number of moles of Zn or U taken, an unknown mass of Zn or U was estimated. Uranium metal was estimated by the method with accuracy comparable with the results from inductively coupled plasma optical emission spectroscopic analysis. The technique was found to be simple, accurate and hands free for the estimation of uranium metal. The paper discusses the details of the sensor assembly, calibration, testing, methodology development and results of estimation of zinc and uranium metals using the sensor.

In the present study, apparent diffusivity of hydrogen at different temperatures in 9Cr-1MoVNbN steel was determined using the data obtained from the measurement of hydrogen evolved from specimens charged with hydrogen. Cylindrical specimens of the 9Cr-1MoVNbN steel in normalized condition were charged with hydrogen electrochemically to saturation level. Hot extraction technique was used for collection of hydrogen evolved from the specimens at different temperatures in a chamber. Subsequently, measurement of evolved hydrogen was carried out using a Nafion based proton-exchange-membrane hydrogen sensor (PEMHS). Using these data in the diffusion equation for a finite cylinder, apparent diffusivity of hydrogen in steel was determined at temperatures in the range of 25–400 °C. Hydrogen lost from the specimens prior to start of the collection of hydrogen evolved was estimated. Apparent diffusivity data, earlier obtained, were revised by considering this lost hydrogen in the estimation. Apparent diffusivities calculated using this method agreed well with the values reported in the literature.

Sodium is used as coolant in fast reactors. Sodium adhering to the reactor components is required to be removed before commencement of maintenance activities. In water vapour–carbon dioxide process, sodium is removed from the components by reacting it with water vapour carried by gaseous carbon dioxide. Hydrogen is formed during the above process. Since hydrogen forms an explosive mixture with air beyond explosion limit of 4%, monitoring hydrogen in carbon dioxide is required before being let out to the atmosphere. Quantification of hydrogen also gives an estimate on the progress of the cleaning process. A fuel cell based amperometric hydrogen sensor, H 2 /Pt//Nafion//Pt/O 2 , has been developed and applied for the purpose. The paper discusses the details of the sensor, its response behavior for hydrogen in carbon dioxide and its application for hydrogen monitoring in a simulated lab scale sodium cleaning experiment. The paper also illustrates the application of the sensor to hydrogen monitoring in mock up studies on sodium cleaning of a major component of Prototype Fast Breeder reactor (PFBR) namely Failed Fuel Location Module (FFLM).

Every regular expression can be transformed into a Nondeterministic Finite Automaton (NFA) with or without  transitions. A well known algorithm called subset construction technique is used for conversion of NFA into DFA. In this paper, initially, the construction of the position automaton is given for the same. Also, the algorithm to convert this Position Automaton into DFA using subset construction technique is discussed. AMS MSC2010 Certification: 68Q45, 68Q70

Sodium is used as a coolant in primary and secondary heat transport systems of Liquid Metal cooled Fast Breeder Reactors (LMFBR). The Prototype Fast Breeder Reactor (PFBR) is in advanced stage of construction at Kalpakkam, India. Under Sodium Ultra Sonic Scanner (USUSS) is used to image the components dipped in sodium and more specifically the gap between Sub Assembly (SA) heads and the control plug. This is essential to confirm that no SA is protruding from its position. USUSS has to be qualified in sodium before its use in the reactor. After sodium testing, sodium adhering to the USUSS needs to be removed to prevent reaction with oxygen and moisture present in air when it is taken out. The sodium removal process is based on the use of moist carbon-di-oxide (CO2) at a temperature of about 353 K. The reaction rate is controlled by varying the ratio of CO2 to moisture. Hydrogen released during the reaction of sodium with moisture is continuously monitored to ensure safe limits of hydrogen concentration. This paper describes the details of the experimental setup used in a cleaning pit for the removal of sodium adhering on USUSS and the technical details of the cleaning process.

Host plant resistance has been a valuable tool in the management of planthoppers. The experiment was carried out to assess the level of total phenols, Ortho-dihydroxy phenols, Phenols, crude silica and total sugars in BPH (Brown Plant Hopper) affected rice leaves. Resistant varieties showed high amount of phenols, O.D. Phenols and crude silica as against low quantity of total sugars. These, biochemical basis of resistant method is also identifying the resistant variety against brown planthopper (Nilaparvata lugens) in rice.

Electro-reduction of solid UO 2 to U has been studied with molten CaCl 2 or LiCl as the electrolyte medium. Electro-reduction of thick (>3 mm), powder compacted and sintered pellets of UO 2 showed incomplete reduction resulting in a mixture of uranium metal and UO 2 . The extent of reduction of UO 2 to U was determined by employing a novel method called ‘metal estimation by hydrogen sensor (MEHS)’, in which the hydrogen evolved during the reaction of U metal in the reduced product with con. HBr was measured using an in-house developed polymer electrolyte based amperometric hydrogen sensor. The results of our investigations on incompletely reduced UO 2 pellets in both CaCl 2 and LiCl melts showed that the extent of reduction of different regions of the oxide pellet was different. It varied from 88.3% on the surface of the pellet as against 3.7% towards the centre bulk during electro-reduction in CaCl 2 (at 1173 K). The metallisation was found restricted to the surface of the pellets reduced in LiCl melt (at 923 K). Electro-reduction of small chunks of UO 2 pellet in CaCl 2 melt resulted in products with lower extent of reduction. Based on the measurements, a probable mechanism on the propagation of reduction through the solid UO 2 matrix during the electrochemical reduction process has been proposed.