Remote magneto-elastic analyte, viscosity and temperature sensing apparatus and associated methods of sensing

An analyte, viscosity, or temperature sensing apparatus for operative arrangement within a time-varying magnetic field, including a sensor with an outer surface that is chemically, frictionally, or thermally responsive and adhered to a base magnetostrictive element, and a receiver to measure a first and second value for magneto-elastic emission intensity of the sensor taken at, respectively, a first and second interrogation frequency. A change in mass or a change in material stiffness of the sensor due to the responsiveness, the viscosity and mass density of a fluid therearound, or the temperature, can be identified. The receiver, alternatively, measures a plurality of successive values for magneto-elastic emission intensity of the sensor taken over an operating range of successive interrogation frequencies to identify a value for the sensor's magneto-elastic resonant frequency (a fundamental frequency or harmonic thereof). Several sensors in an ordered array will provide a package of information

Magnetoelastic sensing apparatus and method for remote pressure query of an environment

A pressure sensing apparatus for operative arrangement within an environment, having: a sensor comprising a hermetically-sealed receptacle, at least one side of which has an flexible membrane to which a magnetically hard element is attached. Enclosed within the receptacle is a magnetostrictive element that vibrates in response to a time-varying magnetic field. Also included is a receiver to measure a plurality of successive values for magneto-elastic emission intensity of the sensor taken over an operating range of successive interrogation frequencies to identify a resonant frequency value for the sensor. Additional features include: (a) the magnetically hard element may be adhered to an inner or outer side of, or embedded within, the membrane; (b) the magnetostrictive element can include one or more of a variety of different pre-formed, hardened regions; (c) the magneto-elastic emission may be a primarily acoustic or electromagnetic emission; and (d) in the event the time-varying magnetic field is emitted as a single pulse or series of pulses, the receiver unit can detect a transitory time-response of the emission intensity of each pulse (detected after a threshold amplitude value for the transitory time-response is observed). A Fourier transform of the time-response can yield results in the frequency domain. Also, an associated method of sensing pressure of an environment is included that uses a sensor having a magnetostrictive element to identify a magneto-elastic resonant frequency value therefore. Using the magneto-elastic resonant frequency value identified, a value for the pressure of the environment can be identified

Finite Element Analysis of Cardiovascular Stents

The cardiovascular diseases have become contemporary and continuously growing healthcare problems. The main reasons for such problems are the intra-vessel depositions of plaque, cholesterol, etc., that give rise to thrombus formation, arterial blockage and stenosis. A traditional cure for said problems is to implant a stent. According to the “Guidance for Industry and FDA Staff - Non-Clinical Engineering Tests and Recommended Labeling for Intravascular Stents and Associated Delivery Systems”, an intravascular stent is a tubular structure intended for permanent implant in native or graft vasculature. The stent is designed to provide mechanical radial support after deployment. This support is meant to enhance vessel patency over the life of the device. Once the stent reaches the intended location, it is expanded by a balloon or self-expanding mechanisms described below. There are two types of stents: the so-called balloon-expandable stents and self-expanding stents. The balloon-expandable stents are expanded by a catheter. They retain the required diameter after deflation of the catheter. The self-expandable stents are expanded from the pre-deployed to the post-deployed diameter size in absence of a catheter. This can be a result of the properties of the material or/and geometry. This work presents the finite element analysis (FEA) of mechanical behavior of balloon-expandable stents, produced from stainless steel 316L and Cobalt-Chromium alloy L-605

HPLC detection of dehydroepiandrosterone in food additives by using normal phase HPLC

A normal-phase High Performance Liquid Chromatography (HPLC) method was developed for the determination of dehydroepiandrosterone (DHEA) in food supplements. We have used an HPLC 200 (Perkin Elmer, USA) with a spectrophotometric detector LC-785A (Bioanalytical systems, USA) and a thermostat (Perkin Elmer, Waltham, MA, USA). We have chosen isocratic HPLC elution, column: LiChrospher (100 DIOL 250 x 4 mm х 5 μm), mobile phase: acetonitrile: water = 98: 2 v/v, flow rate: 1 ml/min. and detection at λ = 202 nm. We have found that this method allows fast and selective qualitative and quantitative determination of DHEA in pharmaceutical products

Metabolite Profile and Antioxidant Activity of Some Species of Genus Scutellaria Growing in Bulgaria

Until now, the interest to plants from genus Scutellaria in Bulgaria has been focused mainly on the terpenes in them. The purpose of this study is to enrich the information on the composition of the Bulgarian Scutellaria species in terms of both polyphenolic content as well as primary metabolites such as mono-, oligosaccharides and organic acids. An aerial part of three Scutellaria species growing in four low mountain regions of Southern Bulgaria was used. The flavonoids scutellarin, baicalin, baicalein, wogonin, wogonoside, luteolin, chrysin and a caffeoyl phenylethanoid glycoside-verbascoside have been identified via HPLC in different extracts from Scutellaria altissima, Scutellaria albida and Scutellaria galericulata. The antioxidant activity of the extracts has been evaluated. The Scutellaria altissima from Mezek and Scutellaria galericulata from Parvenets we studied, which are the richest in flavonoids (represented mainly by baicalin, scutellarin and wogonoside), show the highest Oxygen Radical Absorption Capacity. Hydroxyl Radical Averting Capacity of Scutellaria albida from Mezek and Scutellaria altissima from Bachkovo is the most pronounced, probably due to the content of scutellarin and luteolin and chrysin, respectively. Antioxidant activity of aqueous, methanolic and 70% and 96% ethanol extracts were also determined by the electrochemical method

Metabolite Profile and Antioxidant Activity of Some Species of Genus Scutellaria Growing in Bulgaria

Until now, the interest to plants from genus Scutellaria in Bulgaria has been focused mainly on the terpenes in them. The purpose of this study is to enrich the information on the composition of the Bulgarian Scutellaria species in terms of both polyphenolic content as well as primary metabolites such as mono-, oligosaccharides and organic acids. An aerial part of three Scutellaria species growing in four low mountain regions of Southern Bulgaria was used. The flavonoids scutellarin, baicalin, baicalein, wogonin, wogonoside, luteolin, chrysin and a caffeoyl phenylethanoid glycoside-verbascoside have been identified via HPLC in different extracts from Scutellaria altissima, Scutellaria albida and Scutellaria galericulata. The antioxidant activity of the extracts has been evaluated. The Scutellaria altissima from Mezek and Scutellaria galericulata from Parvenets we studied, which are the richest in flavonoids (represented mainly by baicalin, scutellarin and wogonoside), show the highest Oxygen Radical Absorption Capacity. Hydroxyl Radical Averting Capacity of Scutellaria albida from Mezek and Scutellaria altissima from Bachkovo is the most pronounced, probably due to the content of scutellarin and luteolin and chrysin, respectively. Antioxidant activity of aqueous, methanolic and 70% and 96% ethanol extracts were also determined by the electrochemical method

ECOLOGICAL PROFILES OF HARVESTMEN (ARACHNIDA, OPILIONES) FROM VITOSHA MOUNTAIN (BULGARIA): A MIXED MODELLING APPROACH USING GAMS

Volume: 33Start Page: 256End Page: 26

The Harvestmen Fauna (Opiliones, Arachnida) of the City of Sofia (Bulgaria) and its Adjacent Regions

<p>This is the dataset for:</p> <p>Plamen G. Mitov, Ivailo L. Stoyanov (2004) The Harvestmen Fauna (Opiliones, Arachnida) of the City of Sofia (Bulgaria) and its Adjacent Regions. In: L. Penev, J. Niemelä, D. J. Kotze & N. Chipev (Eds.) Ecology of the City of Sofia. Species and Communities in an Urban Environment, Pensoft, 319-354.</p> <p><strong>Abstract:</strong> This is the first paper dealing with the opilionid fauna of urban park-areas (located in the city of Sofia) in Bulgaria. In addition, the harvestmen fauna of the regions surrounding the city of Sofia is summarized. The faunistic list presents data on the 32 species hitherto found in the covered area. Two of them (<em>Trogulus closanicus</em> and <em>Rilaena serbica</em>) are new to the Bulgarian fauna, and a further one, referred herein as <em>Rilaena</em> cf. <em>serbica</em>, is currently of unclear taxonomical status. A detailed analysis of the opilionid assemblages (both local and regional) under study is provided, and hypotheses concerning the genesis and development of the urban fauna are presented.</p> <p>This dataset includes both the raw (presence-absence) community data as well as the summarized data from Table 1 and Table 2 in the paper.</p

Allozyme genetic polymorphism in Bulgarian honey bee (Apis mellifera L.) populations from the south-eastern part of the Rhodopes

Allozyme genetic polymorphism in Bulgarian honey bee populations from four different locations in the south-eastern part of the Rhodopes Mountain was studied on six enzymic systems (MDH, ME, EST, ALP, PGM and HK) corresponding to six genetic loci. Allozyme analysis revealed that all studied loci were polymorphic in almost all investigated populations. The observed heterozygosity was found to range from 0.110 to 0.208 and Nei's genetic distance – between 0.016 and 0.061 among the studied populations. These honey bee populations were clustered in two groups in the UPGMA dendrogram. The Tihomir population was in a separate clade while other three populations (Kardzhali, Krumovgrad and Dolni Yurutci) were grouped together