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Sample records for acoustic esr

  1. ESR Dosimetry

    International Nuclear Information System (INIS)

    ESR dosimetry is widely used for several applications such as dose assessment in accidents, medical applications and sterilization of food and other materials. In this work the dosimetric properties of natural and synthetic Hydroxyapatite, Alanine, and 2-Methylalanine are presented. Recent results on the use of a K-Band (24 GHz) ESR spectrometer in dosimetry are also presented

  2. ESR dating of pseudotachylite

    Science.gov (United States)

    Shimada, A.; Toyoda, S.; Takagi, H.; Arita, K.

    2002-12-01

    ESR (electron spin resonance) dating method has been used to determine the ages of quaternary events. When a mineral receives natural radiation, a part of paired electrons in quartz are ionized, and are trapped by lattice defects and impurties as unpaired electrons. The amount of unpaired electrons increases with time. The ESR age is obtained by dividing the total dose of natural radiation by the natural dose rate. Gamma ray doses are given to the sample to obtain the total dose by extrapolating the dose response of the signal intensity to the zero ordinate. The natural dose rate is calculated from U, Th, and K concentrations, and so on. Quartz is one of the promising minerals useful for ESR dating. In the present paper, we attempted to obtain ages of a land slide event. We collected pseudotachylite from Lantan, Himalaya. A land of about 4 km in diameter has found to have slid several kilometers resulting in pseudotachylite at the base. The samples were gently crushed sieved and soaked in 6N HCl for 1 night and then in 20% HF for two hours, but quartz grains were too small to be extracted. However, ESR signals of characteristic quartz were observed. As long as the sample is uniform, it is not crucial to extract pure quartz grains. With the usual procedure of ESR dating, gamma ray irradiation and ESR measurements, we obtained accumulated natural doses of 290 to 450 Gy. The concentrations of radioactive elements, K, U, Th, which give most of the natural dose to quartz grains, were measured by the low background gamma ray spectrometry. We obtained 7.62 ppm of uranium, 21.1 ppm of thorium, and 3.72% of K2O. Assuming the cosmic dose rate of 0.1mGy/y, we obtained 6.08 mGy/y as the natural dose rate. The ESR ages are obtained by dividing the accumulated doses by the natural dose rate to be 49ka from Al center signal (an electronic hole trapped at Al impurity in quartz) and 74ka from Ti center signal (an electron trapped at Ti impurity in quartz) for a sample, and 56ka and

  3. ESR teleradiology survey: results.

    Science.gov (United States)

    2016-08-01

    With recent developments of teleradiology technology and services, it has become necessary to better evaluate its extent and use among different countries in Europe. With this goal in mind, the ESR launched two specific surveys intended to gather the current state of adoption and implementation of teleradiology in clinical practice. A special focus on differentiating between insourcing teleradiology services among partners of the same organisation and outsourcing to external services was an essential part of the design of these surveys. The first survey was addressed to 44 national societies of different countries in Europe, while the second survey was intended for all practicing radiologist ESR members. While the results of these surveys reported here may provide a wealth of information to better understand the trends in adoption of teleradiology in Europe, they only represent a snapshot at a certain point in time. The rapid development of telecommunication tools as well as a fundamental change in practice and healthcare economics will certainly influence these observations in the upcoming years. These data, however, will provide objective and relevant parameters for supporting the efforts of experts and policy makers in promoting appropriate criteria and guidelines for adequate use of teleradiology in clinical practice. Main Messages • Understand concepts and challenges of teleradiology • Provide insight into current trends and solutions for teleradiology • Compare differences in teleradiolgy strategies between countries in Europe • Establish a reference on statistical data of usage of teleradiology in Europe. PMID:27188379

  4. Acoustic detection of electron spin resonance

    Science.gov (United States)

    Coufal, H.

    1981-07-01

    The ESR-signal of DPPH was recorded by detecting the modulation of the absorbed microwave power with a gas-coupled microphone. This photo-acoustic detection scheme is compared with conventional ESR-detection. Applications of the acoustical detection method to other modulation spectroscopic techniques, particularly NMR, are discussed.

  5. ESR detection of irradiated seashells

    Energy Technology Data Exchange (ETDEWEB)

    Raffi, J. [Laboratoire de Recherche sur la Qualite des Aliments, Faculte de Saint-Jerome, Marseille (France); Hasbany, C. [Laboratoire de Recherche sur la Qualite des Aliments, Faculte de Saint-Jerome, Marseille (France)]|[Laboratoire de Chimie des Produits Naturels, Faculte de Saint-Jerome, Marseille (France); Lesgards, G. [Laboratoire de Chimie des Produits Naturels, Faculte de Saint-Jerome, Marseille (France); Ochin, D. [Institut Agricol et Alimentaire de Lille (France). Lab. de Microbiologie et d`Hygiene Alimentaire

    1996-11-01

    Among the protocols for identification of irradiated foodstuffs submitted to the European Committee of Standardization, two using ESR (food containing bone or cellulose) were finally accepted as official `draft European standards` in Berlin on 9-10 June 1994. We present here some new results for oyster and mussel shells, and an ESR draft protocol is proposed. (author).

  6. Isotope Effects in ESR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Werner Herrmann

    2013-06-01

    Full Text Available In order to present the relationship between ESR spectroscopy and isotope effects three levels are considered: (i ESR spectroscopy is described on a general level up to the models for interpretation of the experimental spectra, which go beyond the usually used time and mass independent spin-Hamilton operator, (ii the main characteristics of the generalized isotope effects are worked out, and finally (iii the basic, mainly quantum mechanical effects are used to describe the coupling of electron spins with the degrees of freedom, which are accessible under the selected conditions, of the respective paramagnetic object under investigation. The ESR parameters and the respective models are formalized so far, that they include the time and mass depending influences and reflect the specific isotope effects. Relations will be established between the effects in ESR spectra to spin relaxation, to spin exchange, to the magnetic isotope effect, to the Jahn-Teller effects, as well as to the influence of zero-point vibrations. Examples will be presented which demonstrate the influence of isotopes as well as the kind of accessible information. It will be differentiated with respect to isotope effects in paramagnetic centres itself and in the respective matrices up to the technique of ESR imaging. It is shown that the use of isotope effects is indispensable in ESR spectroscopy.

  7. ESR dosimetry: achievements and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Baffa, O., E-mail: baffa@usp.br [Universidade de Sao Paulo, Departamento de Fisica, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, Sao Paulo (Brazil)

    2015-10-15

    Full text: Electron Spin Resonance (ESR), also known as Electron Paramagnetic Resonance (EPR) and more recently as Electron Magnetic Resonance (Emr), is a spectroscopy technique able to detect unpaired electrons such as those created by the interaction ionizing radiation with matter. When the unpaired electrons created by ionizing radiation are stable over some reasonable time, ESR can be used to measure the radiation dose deposited in the material under study. In principle, any insulating material that satisfies this requisite can be used as a dosimeter. ESR has been used in retrospective dosimetry in case of radiological accidents using natural constituents of human body such as teeth, bones and nails as well as fortuitous materials as sugar, sweeteners and plastics. When using teeth the typical detected dose is 0.5 Gy for, for X-Band spectrometers (9 GHz) and even lower doses if higher frequency spectrometers are used. Clinical dosimetry is another area of potential use of this dosimetric modality. In this application the amino acid alanine has been proposed and being used. Alanine dosimeters are very easy to prepare and require no complicated treatments for use. Alanine/ESR dosimetry satisfies many of the required properties for clinical applications such as water equivalent composition, independence of response for the energy range used in therapy and high precision. Other organic materials such as ammonium tartrate are being investigated to increase the sensitivity of ESR for clinical applications. Finally, industrial applications can also benefit from this dosimetry. The challenges to expand applications, the number of users and research groups of ESR dosimetry will be discussed. (Author)

  8. ESR Perspective on Clinical Audit

    Directory of Open Access Journals (Sweden)

    Maurizio Centonze

    2011-05-01

    Full Text Available In October 2009, the European Commission published"nguidelines (Radiation Protection No. 159 on Clinical"nAudit for medical radiology-including Diagnostic"nRadiology, Nuclear Medicine and Radiotherapy-in"norder to improve the implementation of article 6.4 of"nthe Council Directive 97/43/ EURATOM, on health"nprotection of individuals against the dangers of ionizing"nradiation in relation to medical exposure. In article 6.4"nit is stated that "Clinical Audits shall be carried out"nin accordance with national procedures". However,"nthere is a wide variation in the understanding and"nimplementation of Clinical Audit in Europe and"nworldwide. The interpretation of the term audit and"nits differentiation from regulation, quality assurance,"naccreditation and research also differs across Europe."nIn January 2010, the Audit & Standards Subcommittee"nof the European Society of Radiology (ESR published"na document on the ESR perspective on Clinical Audit"nin an effort to define the scope of Clinical Audit in a"nway applicable across the European member states and"nradiological organizations."nThe aim of the presentation is to provide a"ncomprehensive outline of ESR perspective on the"naudit process for clinical radiologists and clinical"nradiology departments. The philosophy discussed is"nequally appropriate for interventional and diagnostic"nradiologists.

  9. ESR dating of tooth enamel samples

    International Nuclear Information System (INIS)

    Five tooth samples from the palaeoanthropological site of Jinniushan were dated with both electron-spin-resonance (ESR) and uranium-series techniques. The ESR age of about 230 ka is in good agreement with the U-series dating result, which confirms the hypothesis of possible coexistence of Homo erect us and Homo sapiens in China. Problems in ESR dating are discussed such as: 1) inappropriate of simple exponential extrapolation for accumulated dose determination; 2)experimental measurement of alpha detection efficiency and radon emanation and 3)selection of U-uptake model

  10. Physics book: CRYRING@ESR

    Science.gov (United States)

    Lestinsky, M.; Andrianov, V.; Aurand, B.; Bagnoud, V.; Bernhardt, D.; Beyer, H.; Bishop, S.; Blaum, K.; Bleile, A.; Borovik, At.; Bosch, F.; Bostock, C. J.; Brandau, C.; Bräuning-Demian, A.; Bray, I.; Davinson, T.; Ebinger, B.; Echler, A.; Egelhof, P.; Ehresmann, A.; Engström, M.; Enss, C.; Ferreira, N.; Fischer, D.; Fleischmann, A.; Förster, E.; Fritzsche, S.; Geithner, R.; Geyer, S.; Glorius, J.; Göbel, K.; Gorda, O.; Goullon, J.; Grabitz, P.; Grisenti, R.; Gumberidze, A.; Hagmann, S.; Heil, M.; Heinz, A.; Herfurth, F.; Heß, R.; Hillenbrand, P.-M.; Hubele, R.; Indelicato, P.; Källberg, A.; Kester, O.; Kiselev, O.; Knie, A.; Kozhuharov, C.; Kraft-Bermuth, S.; Kühl, T.; Lane, G.; Litvinov, Yu. A.; Liesen, D.; Ma, X. W.; Märtin, R.; Moshammer, R.; Müller, A.; Namba, S.; Neumeyer, P.; Nilsson, T.; Nörtershäuser, W.; Paulus, G.; Petridis, N.; Reed, M.; Reifarth, R.; Reiß, P.; Rothhardt, J.; Sanchez, R.; Sanjari, M. S.; Schippers, S.; Schmidt, H. T.; Schneider, D.; Scholz, P.; Schuch, R.; Schulz, M.; Shabaev, V.; Simonsson, A.; Sjöholm, J.; Skeppstedt, Ö.; Sonnabend, K.; Spillmann, U.; Stiebing, K.; Steck, M.; Stöhlker, T.; Surzhykov, A.; Torilov, S.; Träbert, E.; Trassinelli, M.; Trotsenko, S.; Tu, X. L.; Uschmann, I.; Walker, P. M.; Weber, G.; Winters, D. F. A.; Woods, P. J.; Zhao, H. Y.; Zhang, Y. H.

    2016-09-01

    The exploration of the unique properties of stored and cooled beams of highly-charged ions as provided by heavy-ion storage rings has opened novel and fascinating research opportunities in the realm of atomic and nuclear physics research. Since the late 1980s, pioneering work has been performed at the CRYRING at Stockholm (Abrahamsson et al. 1993) and at the Test Storage Ring (TSR) at Heidelberg (Baumann et al. 1988). For the heaviest ions in the highest charge-states, a real quantum jump was achieved in the early 1990s by the commissioning of the Experimental Storage Ring (ESR) at GSI Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt (Franzke 1987) where challenging experiments on the electron dynamics in the strong field regime as well as nuclear physics studies on exotic nuclei and at the borderline to atomic physics were performed. Meanwhile also at Lanzhou a heavy-ion storage ring has been taken in operation, exploiting the unique research opportunities in particular for medium-heavy ions and exotic nuclei (Xia et al. 2002).

  11. ESR investigations on ion beam irradiated polycarbonate

    Energy Technology Data Exchange (ETDEWEB)

    Chipara, M.I. (Institute for Physics and Technology of Materials, P.O. Box MG-7, Magurele, Bucharest, R-76900 (Romania)); Grecu, V.V. (University of Bucharest, Faculty of Physics, P.O. Box MG-11, Magurele, Bucharest, R-76900 (Romania)); Notingher, P.V. (University Politehnica of Bucharest, Electrotechnical Faculty, 313, Splaiul Independentei, Str., 77206 Bucharest (Romania)); Romero, J.R. (Universidad Central de Venezuela, Facultad de Ingineria, Dept. de Fisica Aplicada, Ciudad Universitaria, Chaguaramos, Caracas (Venezuela)); Chipara, M.D. (Research Institute for Electrotechnics, 45-47 Tudor Vladimirescu, Bd., Bucharest, R-79623 (Romania))

    1994-06-01

    Electron spin resonance (ESR) investigations with a polycarbonate solid state nuclear detector, irradiated with oxygen ions, are reported. The nature of the paramagnetic defects induced by irradiation is discussed. The temperature dependence of resonance line parameters is studied. From the experimental data, obtained by ESR, spectroscopy, the activation energy for defect recombination, the average isotropic exchange integral between paramagnetic defects as well as the average distance between defects, are estimated. Correlations with latent tracks structure are discussed. ((orig.))

  12. Transient melting of an ESR electrode

    Science.gov (United States)

    Kharicha, A.; Karimi-Sibaki, E.; Bohacek, J.; Wu, M.; Ludwig, A.

    2016-07-01

    Melting parameters of ESR process such as melt rate and immersion depth of electrode are of great importance. In this paper, a dynamic mesh based simulation framework is proposed to model melt rate and shape of electrode during the ESR process. Coupling interactions between turbulent flow, temperature, and electromagnetic fields are fully considered. The model is computationally efficient, and enables us to directly calculate melting parameters. Furthermore, dynamic change of electrode shape by melting can be captured. It is necessary to control the feeding velocity of electrode due to melting instabilities in the ESR process. As such, a numerical control is implemented based on the immersion depth of electrode to achieve the steady state in the simulation. Furthermore, the modeling result is evaluated against an experiment.

  13. Time resolved ESR spectroscopy. ESR pulse radiolysis equipment with microsecond time resolution

    Energy Technology Data Exchange (ETDEWEB)

    Beckert, D.; Mehler, K. (Akademie der Wissenschaften der DDR, Leipzig. Zentralinstitut fuer Isotopen- und Strahlenforschung)

    1983-01-01

    Time resolved ESR experiments allow the study of the chemical kinetics as well as spin dynamics of free radicals in the liquid phase. Starting from the physical and chemical requirements the experimental parameters of a universal time resolved ESR spectrometer are derived. The main components of the ESR pulse radiolysis equipment are described and their technical parameters are discussed. By two experimental examples it is shown that at a time resolution of 0.3 ..mu..s a sensitivity of c/sub min/ = 10/sup -6/ mol dm/sup -3/ for simple radical spectra can be achieved.

  14. ESR Measurements on the Polymerization of Liquid Selenium

    NARCIS (Netherlands)

    Koningsberger, D.C.; Wolput, J.H.M.C. van; Rieter, P.C.U.

    1971-01-01

    In an earlier communication ESR measurements on de-oxygenized selenium were announced. The present paper reports on further ESR measurements on liquid de-oxygenized selenium carried out in a temperature interval 240}o{C < T < 420}o{C. The g-value of the ESR signal is found to be 2.03 +/- 0.02. The t

  15. Alanine - ESR dosimetry, feasibility and possible applications

    International Nuclear Information System (INIS)

    Alanine ESR dosimetry presents a great interest for quality controls in radiotherapy. This new developed water equivalent alanine dosimeter allows a reproducible dose measurement, by a non-destructive readout technique in a large dose range. In this paper the stability of the dosimeter response has been shown but also its independence with the energy or the dose rate of the absorbed radiation. Through this different studies, one can broaden the application field of alanine / ESR dosimetry especially for in-vivo dosimetry. The results of the experiments and the intra operative treatment, indicate that this kind of dosimetry seems to be a promising technique for in-vivo quality controls in electron beam, γ ray or X ray radiotherapy. (authors)

  16. Electrochemical Aspects of the ESR Process

    Science.gov (United States)

    Mitchell, Alec

    2016-07-01

    Current passage in the ESR process is accomplished by at least two Faradaic reaction systems, one at the electrode/slag interface and another at the slag/ingot interface. The nature of these reactions has been investigated and is reported to be a function of the alloy composition, current density and slag composition. In this report, data generated from both DC and line- frequency AC ESR operations is used to relate laboratory investigations on these reactions to results obtained in industrial practice. The operating reaction in the line frequency AC melting of simple alloy steels is found to be principally the reversible anodic oxidation of iron (Fe/Fe2+). In the equivalent DC process there is in addition the cathodic deposition of aluminium, resulting in the formation of substantial amounts of D-type alumina inclusions in the ingot. The Faradaic reactions involve energy exchange which should be taken into account in the process energy balance. They also are likely to change the interface physical characteristics such as interfacial tension. The data is extended to the case of low frequency ESR furnaces in which it is found that the extent of the reactions is strongly dependent on current density. It is concluded that the presence of Faradaic reactions in low frequency furnaces is unlikely to lead to quality problems in the alloys and applications for which these processes are used. This conclusion appears to be supported by industrial practice and leads to a further conclusion that low frequency practices in large ESR furnaces could potentially be replaced by simpler DC systems.

  17. ESR dating at Mezmaiskaya Cave, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, A.R. [Department of Chemistry, Williams College, Williamstown, MA, 01267 (United States)]. E-mail: anne.r.skinner@williams.edu; Blackwell, B.A.B. [Department of Chemistry, Williams College, Williamstown, MA, 01267 (United States); Martin, Sara [Department of Chemistry, Williams College, Williamstown, MA, 01267 (United States); Ortega, A. [RFK Science Research Institute, Flushing, NY, 11366 (United States); Blickstein, J.I.B. [RFK Science Research Institute, Flushing, NY, 11366 (United States); Golovanova, L.V. [Laboratory of Prehistory, St. Petersburg (Russian Federation); Doronichev, V.B. [Laboratory of Prehistory, St. Petersburg (Russian Federation)

    2005-02-01

    Mezmaiskaya Cave has yielded more than 10,000 artifacts, thousands of very well preserved faunal remains, and hominin remains, found in seven Middle Paleolithic (Mousterian) and three Upper Paleolithic levels. A complete Neanderthal infant skeleton was preserved in anatomical juxtaposition lying on a large limestone block, overlain by the earliest Mousterian layer, Layer 3. Twenty-four skull fragments from a 1-2 year-old Neanderthal infant, showing post-mortem deformation, occurred in a pit originating in the Mousterian Layer 2 and penetrating into underlying layers 2A and 2B(1). Bone from Layer 2A was dated by AMS {sup 14}C at 35.8-36.3{+-}0.5 kyr BP. Direct dating of Neanderthal bone from Layer 3 gave an age of 29 kyr, but that is now considered to be due to contamination by modern carbon. Fourteen large mammal teeth from Layers 2 through 3 have been dated by standard electron spin resonance (ESR). Low U concentrations in both the enamel and dentine ensure that ESR ages do not depend significantly on the U uptake model, but do depend strongly on the sedimentary dose rates. Assuming a sedimentary water concentration equal to 20 wt%, ESR ages for the Mousterian layers range from 36.2 to 73.0{+-}5.0 ka.

  18. ESR identification of gamma-irradiated albendazole

    Science.gov (United States)

    Çolak, Seyda

    2010-01-01

    The use of ionizing radiation for sterilization of pharmaceuticals is a well-established technology. In the present work, the spectroscopic and kinetic features of the radicals induced in gamma-irradiated solid albendazole samples is investigated at different temperatures in the dose range of 3-34 kGy by electron spin resonance (ESR) spectroscopy. Irradiation with gamma radiation produced two different radical species in albendazole. They were fairly stable at room temperature but relatively unstable above room temperature, giving rise to an unresolved ESR spectrum consisting of three resonance peaks centered at g=2.0057. Decay activation energies of the contributing radical species were calculated to be 47.8 (±13.5) and 50.5 (±9.7) kJ/mol using the signal intensity decay data derived from annealing studies performed at high temperatures. A linear function of the applied dose was found to best describe the experimental dose-response data. Albendazole does not present the characteristics of good dosimetric materials. However, the discrimination of irradiated albendazole from its unirradiated form was possible even 6 months after storage in normal conditions. Based on these findings, it is concluded that albendazole and albendazole-containing drugs can be safely sterilized by gamma radiation and that ESR spectroscopy could be successfully used as a potential technique for monitoring their radiosterilization.

  19. ESR analysis of irradiated frogs' legs and fishes

    International Nuclear Information System (INIS)

    Electron spin resonance (ESR) spectral analysis of different parts (bones, scales, jaw, etc.) from ionized (irradiated) frozen frogs' legs and fishes (brown trout and sardine) were recorded. There is always present, after treatment, a signal due to the irradiation. ESR and ENDOR experiments lead us to assign it to h1 centers from hydroxyapatite, as in the case of other irradiated meat bones. The use of ESR to prove whether one of these foods has been irradiated or not is discussed. (author)

  20. ESR study on carboxymethyl chitosan radicals in an aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Seiichi, E-mail: saiki.seiichi@jaea.go.j [Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Nagasawa, Naotsugu; Hiroki, Akihiro; Morishita, Norio; Tamada, Masao [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Muroya, Yusa; Kudo, Hisaaki [Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Katsumura, Yosuke [Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1195 (Japan)

    2010-03-15

    Carboxymethyl chitosan (CMCTS) at a highly concentrated aqueous solution forms hydrogel by ionizing irradiation. To study on radiation-induced reaction mechanism of CMCTS in an aqueous solution, CMCTS radicals formed by reactions with OH radical were observed by ESR method. As a result of ESR spectral analysis, CMCTS radicals were identified as radicals on carboxymethyl groups.

  1. NMR and ESR characterization of oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Harrell, J.W. Jr.; Kohno, T.; Banu, F.; Hanna, H.S.

    1984-01-01

    It has been shown that relaxation measurements can be useful in characterizing motions in oil shales. High-temperature T/sub 1 rho/ measurements have been shown to be especially useful in showing molecular motions that may be related to the oil producing aliphatic part of the shale. However, in order to more fully exploit relaxation measurements, a more fundamental understanding of the relaxation mechanisms must be obtained. Because the ESR spectra of the Eastern oil shales have been found to be so rich in detail, it may be possible to learn more about the nature of the free radicals in shale than is now known for coal, which has been studied much more extensively. Clearly, additional work on this subject should prove fruitful.

  2. Dosimetry by ESR spectroscopy of alanine

    International Nuclear Information System (INIS)

    Dosimetry based on electron spin resonance analysis of radiation-induced free radicals in amino acids (e.g. L-alanine) is relevant to biological dosimetry applications. Typical features are a wide dose range covering more than 5 decades (1-105Gy), energy independent response for photons above 100 keV, long-term stability of the ESR signal, and fast straightforward readout technique. Typical dosimeter samples, consisting of small pellets of microcrystalline amino acids in paraffin, are rugged, non-toxic, and insensitive to surface contaminations. Moreover, they are prepared homogeneously and inexpensively in large batches and can be evaluated repeatedly and supply archival dosimetry data. They have proven to be highly useful in various applications of radiation processing and sterilization dosimetry, food irradiation, quality control, radiation dosimetry, radiation therapy measurements, and as a reference system for dosimetry mailing intercomparisons. (author)

  3. ESR, electrochemical and reactivity studies of antitrypanosomal palladium thiosemicarbazone complexes

    Science.gov (United States)

    Otero, Lucía; Folch, Christian; Barriga, Germán; Rigol, Carolina; Opazo, Lucia; Vieites, Marisol; Gambino, Dinorah; Cerecetto, Hugo; Norambuena, Ester; Olea-Azar, Claudio

    2008-08-01

    Cyclic voltammetry (CV) and electron spin resonance (ESR) techniques were used in the investigation of novel palladium complexes with bioactive thiosemicarbazones derived from 5-nitrofurane or 5-nitrofurylacroleine. Sixteen palladium complexes grouped in two series of the formula [PdCl 2HL] or [PdL 2] were studied. ESR spectra of the free radicals obtained by electrolytic reduction were characterized and analyzed. The ESR spectra showed two different hyperfine patterns. The stoichiometry of the complexes does not seem to affect significantly the hyperfine constants however we observed great differences between 5-nitrofurane and 5-nitrofurylacroleine derivatives. The scavenger properties of this family of compounds were lower than Trolox.

  4. Analytical model for the growth of ESR signals

    Energy Technology Data Exchange (ETDEWEB)

    Barabas, M.; Bach, A.; Mangini, A.

    1988-01-01

    We have developed an analytical model for the time- and dose-dependency of ESR signals in calcite. The model describes well the observed natural growth and the growth by artificial irradiation of ESR-signals (g = 2.0034 and g = 2.0006) in deep-sea foraminifera. The model shows how to derive the archaeological dose from the artificial growth curve of ESR signals. Applying the model we have determined the lifetime of the signal at g = 2.0006 to be about 350 ka at 2/sup 0/C. The thermal decay of the traps responsible for that signal was shown by heating experiments.

  5. Study of detection of irradiated dried fruits by ESR spectroscopy

    International Nuclear Information System (INIS)

    We focus on dried fruits containing crystalline sucrose chiefly, and study a method for identification of sucrose-radicals in ESR spectra of irradiated dried fruits. We evaluated g-values and widths of ESR signals of irradiated dried fruits and sucrose respectively. The result showed it might be possible to identify sucrose-radicals by g-values and widths. We tried the establishment of criteria for the judgment that the sample has been irradiated. As a result, criteria may be established by normalized peak height of ESR signals. The peak height can be normalized by using standard irradiated alanine pellets. (author)

  6. Ribavirin restores ESR1 gene expression and tamoxifen sensitivity in ESR1 negative breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Sappok Anne

    2011-12-01

    Full Text Available Abstract Tumor growth is estrogen independent in approximately one-third of all breast cancers, which makes these patients unresponsive to hormonal treatment. This unresponsiveness to hormonal treatment may be explained through the absence of the estrogen receptor alpha (ESR1. The ESR1 gene re-expression through epigenetic modulators such as DNA methyltransferase inhibitors and/or histone deacetylase inhibitors restores tamoxifen sensitivity in ESR1 negative breast cancer cell lines and opens new treatment horizons in patients who were previously associated with a poor prognosis. In the study presented herein, we tested the ability of ribavirin, which shares some structural similarities with the DNA-methyltransferase inhibitor 5-azacytidine and which is widely known as an anti-viral agent in the treatment of hepatitis C, to restore ESR1 gene re-expression in ESR1 negative breast cancer cell lines. In our study we identified ribavirin to restore ESR1 gene re-expression alone and even more in combination with suberoylanilide hydroxamic acid (SAHA - up to 276 fold induction. Ribavirin and analogs could pave the way to novel translational research projects that aim to restore ESR1 gene re-expression and thus the susceptibility to tamoxifen-based endocrine treatment strategies.

  7. Influences of sample preparations on dentine ESR signals

    International Nuclear Information System (INIS)

    The work is to study influences of sample preparations on dentine ESR (electron spin resonance) signals, in order to use dentine samples for dose reconstruction, which has been performed with enamel samples. The dentine and enamel samples were collected from non-irradiated adult teeth and prepared by mechanical or mechanical plus chemical methods. The samples were scanned by an ESR spectrometer before and after their irradiation by 60Co γ-rays. The sensitivities of ESR signals of dentine and enamel samples to irradiation dose differed significantly among different sample preparation methods. The results show that dentine samples mechanically and chemically prepared have good enough ESR response to low dose γ-ray irradiations, and it is possible to use the dentine samples for dose reconstruction, as a substitution to enamel samples when they are short of supply. (authors)

  8. Study on identification of irradiated food containing cellulose by ESR

    International Nuclear Information System (INIS)

    The fast development and application of food irradiation technology signify the necessity and urgency to research on effective detection method for irradiated food. In this paper, we report a preliminary study in this area with dried chili powder, peanuts and strawberry seeds. The food samples were irradiated to 0.5, 1.0, 3.0, 5.0 and 10.0 kGy by 60Co gamma rays. The relation between ESR intensity and irradiation dose, and correlation R2, were studied. The results showed that the ESR signal intensity is positively related with the dose. ESR intensity of the strawberry increased the slowest with the dose, and the chili powder had the most accurate calculation. Accurate dose-effect curves, however, require repeating tests and further studies are needed to verify the ESR results. (authors)

  9. Irradiation detection of coffee mate by electron spin resonance (ESR)

    International Nuclear Information System (INIS)

    Un-irradiated coffee mate samples do not exhibit any ESR signal. However, the samples exposed to UV and gamma radiation exhibit an ESR singlet and a large unresolved ESR signal, respectively. The dose-response curves of the samples exposed to UV and gamma radiations were found to be described well by an exponential and linear functions, respectively. Variable temperature and fading studies at room temperature showed that the radiation-induced radicals in coffee mate sample are very sensitive to temperature. The discrimination between un-irradiated and irradiated coffee mate samples can be done just comparing their ESR spectra. However, determination of the radiation dose received by the sample cannot be possible because of the fast decay of signal intensity at room temperature.

  10. ESR STUDY OF PLASMA-TREATED POLYTETRAFLUOROETHYLENE FILMS

    Institute of Scientific and Technical Information of China (English)

    ZHOU Maotang; WANG Shicai; LIU Guizhen; CHEN Jie

    1990-01-01

    The plasma treatment of polytetrafluoroethylene (PTFE) films was carried out in a capacitively coupled reactor with external electrodes. The free radicals generated in the process of treatment were detected by ESR techniques. The ESR spectra tended to indicate that the free radicals of the plasma-treated PTFE film sample were turned into peroxy radicals on exposure to air. The extrema separation (W) of the ESR spectrum of the peroxy radical increased with the lowering temperature and underwent a sudden change within the temperature range of 170 to 190K. The ESR spectrum observed at 77K was quite different from that observed at room temperature. Finally, the effects of treatment time, input power and system pressure on radical concentration of the treated samples were studied. The attenuation of the peroxy radical at room temperature was also investigated.

  11. ESR of ice and environmental assessment

    International Nuclear Information System (INIS)

    In the environment of the earth, liquid water exists abundantly, but it cannot be seen in other environment in the solar system. The environment covered with solid water is seen in many celestial bodies, but these ices are not pure water, and contain NH3, SO2, CH4, CO, CO2 and others. Also the existence of solid CO2 on Mars, solid SO2 on Io and solid CH4 on Triton has been known. In many celestial bodies without atmosphere and with ice, it is considered that the ice causes dissociation and ionization due to the effects of ultraviolet ray, solar wind and cosmic γ ray. As the basis of examining these phenomena, the authors made various ices, and studied on the irradiation effect of gamma ray and ultraviolet ray in the laboratory. It became clear by the research using ESR that various kinds of radicals were formed in the ices by the irradiation. The age of the radicals formed in ices means the age of the events that extinguish the radicals occurred on the surfaces of the celestial bodies after ice formation. The problems in the principle of age measurement are the real formation of radicals, the stability of radicals, and the saturation of radical concentration. The research of these problems for H2O and SO2 is reported. (K.I.)

  12. ESR studies of the magnetism of Ru-1212

    International Nuclear Information System (INIS)

    We have studied, by ESR, the systems of Ru-1212 over the temperature range 100-300 K, in the normal and magnetic phases. We have found that the ferromagnetic line appears at a temperature higher than the magnetic ordering temperature as determined by neutron diffraction. We also show a correlation between the temperature dependence of the intensity and width of the ESR lines, the intensity of magnetic absorption lines and the DC magnetization measurements

  13. ESR dosimetry using eggshells and tooth enamel for accidental dosimetry

    International Nuclear Information System (INIS)

    The CO2- signal of eggshells showed a good dose linearity and was appropriate in the wide dose range from 1 to 10 kGy, while ESR signal of CO2- in sea and fresh water shells were saturated at a dose od below 10 kGy. The minimum detectable dose and G-value of CO2- in eggshells were estimated 0.3 Gy and 0.28, respectively. The lifetime of CO2- in eggshells could not be determined exactly because of overlapping organic signals, however it is still sufficiently long for practical use as ESR dosimeter materials. Various bird's or reptile's eggshells would be available as natural retrospective ESR dosimeter materials after nuclear accidents. Eggshells will be useful for the food irradiation dosimetry in the dose range of about a few kGy. Tooth enamel is one of the most useful dosimeter materials in public at a accident because of its high sensitivity. ESR dosimetry will replace TLD in near future if the cost of an ESR reader is further reduced . (author)

  14. CRYRING@ESR: present status and future research

    Science.gov (United States)

    Lestinsky, M.; Bräuning-Demian, A.; Danared, H.; Engström, M.; Enders, W.; Fedotova, S.; Franzke, B.; Heinz, A.; Herfurth, F.; Källberg, A.; Kester, O.; Litvinov, Y.; Steck, M.; Reistad, D.; Simonsson, A.; Skeppstedt, Ö.; Stöhlker, T.; Vorobjev, G.; the CRYRING@ESR working Group

    2015-11-01

    The former storage ring CRYRING has been shipped from the Manne Siegbahn Laboratory in Stockholm to Darmstadt as a Swedish in-kind contribution to FAIR. At its new location downstream of ESR all ion species presently accessible in ESR can be transferred to CRYRING, in which ions with rigidities between 1.44 and 0.054 Tm can be stored. The original Swedish layout has been modified by reconfiguring the sequence of straight sections and by slightly increasing the circumference to ESR/2. Ions can be injected from ESR or from an independent 300 keV/u RFQ test injector. The instrumentation of the ring includes an RF drift tube system for acceleration and deceleration (1 T s-1, with a possibility for an upgrade to 7 T s-1), electron cooling, a free experimental section, and both fast and slow extraction of ions. We report on the present progress of this project, give a prospective timeline, and summarize the new research which will be enabled by this project. First beam for commissioning of the storage ring is expected for 2015, final bakeout to restore ultrahigh vacuum conditions in 2016 and ion beams injected through ESR in ˜2017.

  15. Radiostability of butylated hydroxytoluene (BHT): An ESR study

    Science.gov (United States)

    Tuner, H.; Korkmaz, M.

    2007-05-01

    In the present work, the effects of gamma radiation on solid butylated hydroxytoluene (BHT), which is used as an antioxidant, were investigated by ESR spectroscopy. While unirradiated BHT presented no ESR signal, irradiated BHT exhibited an ESR spectrum with many resonance maxima and minima spread over a magnetic field range of 12 mT and centered at about g = 2.0026. Weak satellite and central intense resonance lines, likely, originated from radical species of different stabilities and ratios were observed to be responsible from experimental ESR spectrum of gamma irradiated BHT. Studies based on the variations of the observed line intensities and spectrum area under different experimental conditions were carried out and characteristic features of the radical species responsible from experimental ESR spectrum were determined. Mesomeric radical species of different stabilities providing to BHT a G value of 0.25 were believed to be induced in gamma irradiated BHT. While species responsible from weak satellite lines were unstable, the species causing central intense lines were found to be relatively stable. BHT belongs to a class of compounds with low radiosensitivity ( G = 0.25). This feature of BHT enables the feasibility of radiosterilizations of the products containing BHT as antioxidant without very much loss from its antioxidant benefit. BHT has been shown to provide an opportunity in the estimation of applied radiation dose with a reasonable accuracy if an appropriate mathematical function is used to describe experimental dose-response data.

  16. Radiostability of butylated hydroxytoluene (BHT): An ESR study

    Energy Technology Data Exchange (ETDEWEB)

    Tuner, H. [Department of Physics Engineering, Faculty of Engineering, Hacettepe University, Beytepe, Ankara 06800 (Turkey)]. E-mail: htuner@hacettepe.edu.tr; Korkmaz, M. [Department of Physics Engineering, Faculty of Engineering, Hacettepe University, Beytepe, Ankara 06800 (Turkey)

    2007-05-15

    In the present work, the effects of gamma radiation on solid butylated hydroxytoluene (BHT), which is used as an antioxidant, were investigated by ESR spectroscopy. While unirradiated BHT presented no ESR signal, irradiated BHT exhibited an ESR spectrum with many resonance maxima and minima spread over a magnetic field range of 12 mT and centered at about g = 2.0026. Weak satellite and central intense resonance lines, likely, originated from radical species of different stabilities and ratios were observed to be responsible from experimental ESR spectrum of gamma irradiated BHT. Studies based on the variations of the observed line intensities and spectrum area under different experimental conditions were carried out and characteristic features of the radical species responsible from experimental ESR spectrum were determined. Mesomeric radical species of different stabilities providing to BHT a G value of 0.25 were believed to be induced in gamma irradiated BHT. While species responsible from weak satellite lines were unstable, the species causing central intense lines were found to be relatively stable. BHT belongs to a class of compounds with low radiosensitivity (G = 0.25). This feature of BHT enables the feasibility of radiosterilizations of the products containing BHT as antioxidant without very much loss from its antioxidant benefit. BHT has been shown to provide an opportunity in the estimation of applied radiation dose with a reasonable accuracy if an appropriate mathematical function is used to describe experimental dose-response data.

  17. Application of ESR spin label oximetry in food science.

    Science.gov (United States)

    Zhou, Yu-Ting; Yin, Jun-Jie; Lo, Y Martin

    2011-12-01

    Lipid oxidation attributed to the presence of oxygen has long been a focal area for food science research due in early years mainly to its broad impact on the quality and shelf stability. The need to effectively strategize interventions to detect and eventually eliminate lipid oxidation in food remains as evidence on nutritional and health implications continue to accumulate. Electron spin resonance (ESR) spin label oximetry has been shown capable of detecting dissolved oxygen concentration in both liquid and gaseous phases based on the collision between oxygen and stable free radicals. This review aimed to summarize not just the principles and rationale of ESR spin label oximetry but also the wide spectrum of ESR spin label oximetry applications to date. The feasibility to identify in very early stage oxygen generation and consumption offers a promising tool for controlling lipid oxidation in food and biological systems.

  18. Computer enhancement of ESR spectra of magnetite nanoparticles

    Science.gov (United States)

    Dobosz, B.; Krzyminiewski, R.; Koralewski, M.; Hałupka-Bryl, M.

    2016-06-01

    We present ESR measurements of non-interacting magnetic nanoparticle systems. Temperature and orientational dependence of ESR spectra were measured for Fe3O4 nanoparticle coated by dextran or oleic acid, frozen in different magnetic field. Several parameters describing magnetic properties such as g-factor, line width, the anisotropy constant were calculated and discussed. The ESR spectra of investigated nanoparticles were also subjected to Computer Resolution Enhancement Method (CREM). This procedure allows to separate a narrow line on the background of the broad line, which presence in this type of materials was recognized in the recent literature and have been further discussed in the paper. CREM is a valuable tool for monitoring of changes on the surface of magnetic core of nanoparticles.

  19. Predicting ESR Peaks in Copper (II Chelates Having Quadrupolar Coordinating Sites by NMR, ESR and NQR Techniques: A DFT Study

    Directory of Open Access Journals (Sweden)

    Harminder Singh

    2015-06-01

    Full Text Available Computational chemistry was helpful in predicting the number of ESR peaks in Cu (II complexes having a large number of spatially different NMR and ESR active nuclei. The presence of the large Jahn-Teller effect and the high value of spin-orbit coupling constant of the metal ion made the experimental determination of the exact number of ESR peaks quite difficult in such complexes. Fourteen distorted poly-dentate chelating Cu(II complexes included in this study were of two types such as [Cu(gly2] , [Cu(edta]4-,[Cu(tpyX2] (X= Cl, Br, I, NCS and [Cu(en2]2+, [Cu(teta]2+, Cu(tepa]2+ ,[Cu(peha]2+, [Cu(detaX2] (X= Cl, Br, I, NCS.The latter eight complexes belonged to an important class of ligands called polyethylene polyamines. Density functional theory implemented in ADF: 2010.02 was applied. Three parameters of both the ESR (A ten and NQR (NQCC, for the Cu(II and the coordinating atoms of the ligands were obtained from “ESR/EPR program” and two NMR parameters namely the shielding constants (σ and chemical shifts (δ were obtained from “NMR/EPR program” after optimization of the complexes. The species having the same values of these 5 parameters were expected to be spatially equivalent to undergo the same hyperfine interaction with Cu (II.

  20. An alternative procedure for ESR identification of irradiated chicken drumsticks

    Energy Technology Data Exchange (ETDEWEB)

    Bordi, F. (Rome-2 Univ. (Italy). Dip. di Medicina Interna); Fattibene, P.; Onori, S.; Pantaloni, M. (Istituto Superiore di Sanita, Rome (Italy) Istituto Nazionale di Fisica Nucleare, Rome (Italy))

    The ESR spectroscopy is, at present, the most established technique for quantitative analysis of irradiated chicken bone using the additive dose method. In this paper we tried a different approach to the problem analyzing the ESR behavior of a batch of chicken bone samples coming randomly from the market. Using a suitable and standardized sample preparation technique and sample positioning in the microwave cavity, we obtained a coefficient of variation of about 30% for the batch response. The calibration curve, obtained using the batch behavior up to 10 kGy, was used for a quantitative test on unknown samples. (author).

  1. ESR STUDY OF FREE RADICALS IN IRRADIATED POLYAMIDE- 1010

    Institute of Scientific and Technical Information of China (English)

    ZHOU Maotang; ZHANG Lihua; LIU Yayan; CHEN Donglin

    1993-01-01

    Polyamide-1010 samples were irradiated in vacuum at room temperature by Cobalt-60γ-rays. The free radicals formed in irradiation were studied by means of electron spin resonance (ESR)techniques. The ESR spectra consisted of a quartet and a superimposed singlet whichwere attributed to radical - CO - NH - CH - CH2 and - CH2 - C = O, respectively. The effects of temperature and crystallinity on the radicals were discussed and the mechanism for the production and decay of the radicals was also proposed.

  2. Thermal stability of ESR signals in hydrothermal barites

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Fumihiro [Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005 (Japan); Toyoda, Shin, E-mail: toyoda@dap.ous.ac.jp [Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005 (Japan); Banerjee, Debabrata [Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005 (Japan); Planetary Sciences Division, Physical Research Laboratory, Ahmedabad 380009 (India); Ishibashi, Jun-Ichiro [Department of Earth and Planetary Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

    2011-09-15

    Thermal stability of the ESR signals from barites in chimneys deposited from hydrothermal vents is investigated using isothermal and isochronal annealing experiments. A combination of first and second order kinetics is required to explain the results. The Arrhenius plots of the decay rate constants give the activation energies of 1.0-1.3 eV. From the estimated decay rate constants at the sea bottom (3 {sup o}C), the decay rate of the signal was calculated to be less than 2% for the period of 20 ka, suggesting the applicability of the ESR method for dating barites up to about twenty thousand years.

  3. Communication Acoustics

    DEFF Research Database (Denmark)

    Blauert, Jens

    Communication Acoustics deals with the fundamentals of those areas of acoustics which are related to modern communication technologies. Due to the advent of digital signal processing and recording in acoustics, these areas have enjoyed an enormous upswing during the last 4 decades. The book...... the book a source of valuable information for those who want to improve or refresh their knowledge in the field of communication acoustics - and to work their way deeper into it. Due to its interdisciplinary character Communication Acoustics is bound to attract readers from many different areas, such as......: acoustics, cognitive science, speech science, and communication technology....

  4. The ESR spectrum of NO2 in the gaseous state

    NARCIS (Netherlands)

    Schaafsma, T. J.

    1967-01-01

    Existing theory of electron spin rotation spin rotation interaction in a polyatomic free radials was tested by comparing experimental and calculated high field ESR spectra of gaseous NO2. The results of this study suggest that the spin-rotation phenomenon is at least qualitatively understood. but th

  5. ESR of an O3- centre in KCl

    International Nuclear Information System (INIS)

    By means of ESR an ozonide molecular O3- ion was detected in x-irradiated KCl. The principal values of the G-tensor (2.0032, 2.0182, 2.0118) are in excellent agreement with the values found in other host lattices and with CNDO calculations performed earlier. All measurements were carried out at liquid-helium temperatures. (author)

  6. Edge Stabilized Ribbon (ESR); Stress, Dislocation Density and Electronic Performance

    Science.gov (United States)

    Sachs, E. M.

    1984-01-01

    The edge stabilized ribbon (ESR) silicon ribbon was grown in widths of 1, 2.2 and 4.0 inches at speeds ranging from .6 to 7 in/min, which result in ribbon thicknesses of 5 to 400 microns. One of the primary problems remaining in ESR growth is that of thermally induced mechanical stresses. This problem is manifested as ribbon with a high degree of residual stress or as ribbon with buckled ribbon. Thermal stresses result in a high dislocation density in the grown material, resulting in compromised electronic performance. Improvements in ribbon flatness were accomplished by modification of the ribbon cooling profile. Ribbon flatness and other experimental observations of ESR ribbon are discussed. Laser scanner measurements show a good correlation between diffusion length and dislocation density which indicates that the high dislocation densities are the primary cause of the poor current performance of ESR materials. Dislocation densities were reduced and improved electronic performance resulted. Laser scanner data on new and old material are presented.

  7. Acoustic Neuroma

    Science.gov (United States)

    An acoustic neuroma is a benign tumor that develops on the nerve that connects the ear to the brain. ... can press against the brain, becoming life-threatening. Acoustic neuroma can be difficult to diagnose, because the ...

  8. ESR studies on quartz extracted from shallow fault gouges related to the ms 8.0 Wenchuan earthquake - China - implications for ESR signal resetting in quaternary faults

    OpenAIRE

    Liu, Chun-Ru; Yin, Gong-Ming; Zhou, Yong-Sheng; Gao, Lu; Han, Fei; Li, Jian-ping

    2014-01-01

    ESR dating of the most recent fault activity through quartz signal measurement is based on the assumption that the ESR signal experienced zero resetting during the faulting event. However, several laboratory experiments implied that only partial zeroing of quartz ESR signals was possible. In order to verify whether the signal resetting could be complete under natural conditions, we analyzed quartz recovered from fault gouges after the 2008 Ms 8.0 Wenchuan earthquake. The quartz E’ and Al cent...

  9. ESR spectroscopic investigations of the radiation-grafting of fluoropolymers

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, G.; Roduner, E. [University of Stuttgart (Germany); Brack, H.P.; Scherer, G.G. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    ESR spectroscopic investigations have clarified the influence of several preparative parameters on the reaction rates and yields obtained in the radiation-grafting method used at PSI to prepare proton-conducting polymer membranes. At a given irradiation dose, a higher concentration of reactive radical sites was detected in ETFE films than in FEP films. This higher concentration explains the higher grafting levels and rates of the ETFE films found in our previous grafting experiments. Taken together, the in-situ ESR experiments and grafting experiments show that the rates of disappearance of radical species and grafting rates and final grafting levels depend strongly on the reaction temperature and the oxygen content of the system. Average grafted chain lengths were calculated to contain about 1,000 monomer units. (author) 2 figs., 4 refs.

  10. Detection of irradiated chicken by ESR spectroscopy of bone

    Science.gov (United States)

    Duarte, C. L.; Villavicencio, A. L. C. H.; Del Mastro, N. L.; Wiendl, F. M.

    1995-02-01

    Ionizing radiation has been used to treat poultry to remove harmful microorganisms, mainly Salmonella, which contaminates chicken, goose and other fresh and frozen poultry. This microorganism is sensitive to low dose radiation. Thus, irradiating these foods with doses between 1 to 7 kGy results in a large reduction of bacteria. Since it is necessary to determine whether irradiation has occurred and to what extend, this work studied the signal produced by ionizing radiation within the hard crystalline matrix of chicken's bone to establish a control method. Chicken's drumsticks were irradiated and bones separated from flesh were lyophilized and milled. ESR spectrum was then obtained. The ESR signal increased linearly with dose over the range 0.25 to 8.0 kGy. Free radicals evaluated during 30 days after irradiation showed stable in this period.

  11. Detection method of irradiated green tea using ESR

    International Nuclear Information System (INIS)

    With electron spin resonance (ESR) spectroscopy, we revealed various radicals in commercially available Japanese green tea before and after γ-irradiation. The representative ESR spectrum of green tea is composed of sextet centered at g=2.0, a singlet at the same g value and a singlet at g=4.0. The first signal is attributable to a signal with hyperfine interaction of the Mn2+. The second signal is due to an organic free radical. The third signal may originate from the Fe3+. Upon irradiation, a pair of signals was newly appeared at the symmetric positions on both sides of the organic free radical signal. According to the theory of radical production in irradiated solid, a linear relationship is expected between the radiation dose and the radical yield. We determined the unreported irradiation dose by the linear extrapolation. (author)

  12. ESR and related experiments in spin-polarized atomic hydrogen

    International Nuclear Information System (INIS)

    This thesis deals with some experiments in (gaseous) spin-polarized atomic hydrogen. One uses the expression 'stabilized' atomic hydrogen, meaning that by choosing suitable conditions one can suppress the tendency of atoms to recombine into H2 molecules, such that the lifetime of the atomic state is extended by many orders of magnitude. Research is focused at the study of processes that determine the decay rate of polarized H samples, with the ultimate goal of preparing samples of sufficiently high density and at low enough temperature to observe experimentally the behaviour of the (degenerate) quantum gas. ESR (Electron Spin Resonance) appears to be a very suitable measurement technique to study the properties of polarized H. This work describes the introduction of ESR as detection technique, and the first results of an experiment in polarized H using this technique. (orig.)

  13. Electron cooling of highly charged ions in the ESR

    International Nuclear Information System (INIS)

    The ESR storage ring offers the unique opportunity to store and cool fully stripped heavy ions up to uranium at energies between 50 and 370 MeV/u. Measurements of the longitudinal cooling force for several ion species from C6+ to U92+ are presented. A pronounced deviation from the expected q2 scaling was found. Further investigations have been performed to study the influence of magnetic field strength on the longitudinal cooling force. (orig.)

  14. ESR detection procedure of irradiated papaya containing high water content

    Science.gov (United States)

    Kikuchi, Masahiro; Shimoyama, Yuhei; Ukai, Mitsuko; Kobayashi, Yasuhiko

    2011-05-01

    ESR signals were recorded from irradiated papaya at liquid nitrogen temperature (77 K), and freeze-dried irradiated papaya at room temperature (295 K). Two side peaks from the flesh at the liquid nitrogen temperature indicated a linear dose response for 3-14 days after the γ-irradiation. The line shapes recorded from the freeze-dried specimens were sharper than those at liquid nitrogen temperature.

  15. ESR detection procedure of irradiated papaya containing high water content

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Masahiro, E-mail: kikuchi.masahiro@jaea.go.j [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Shimoyama, Yuhei [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Ukai, Mitsuko [Hokkaido University of Education, 1-2 Hachiman-cho, Hakodate, Hokkaido 040-8567 (Japan); Kobayashi, Yasuhiko [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan)

    2011-05-15

    ESR signals were recorded from irradiated papaya at liquid nitrogen temperature (77 K), and freeze-dried irradiated papaya at room temperature (295 K). Two side peaks from the flesh at the liquid nitrogen temperature indicated a linear dose response for 3-14 days after the {gamma}-irradiation. The line shapes recorded from the freeze-dried specimens were sharper than those at liquid nitrogen temperature.

  16. Sistemi liquido cristallini complessi: simulazioni al calcolatore e studi ESR

    OpenAIRE

    Miglioli, Isabella

    2010-01-01

    The aim of this PhD thesis was to study at a microscopic level different liquid crystal (LC) systems, in order to determine their physical properties, resorting to two distinct methodologies, one involving computer simulations, and the other spectroscopic techniques, in particular electron spin resonance (ESR) spectroscopy. By means of the computer simulation approach we tried to demonstrate this tool effectiveness for calculating anisotropic static properties of a LC material, a...

  17. Detection of irradiated chicken by hydrocarbon and ESR methods

    International Nuclear Information System (INIS)

    Chicken meat with bone was irradiated by gamma rays at -19 - 10degC. Both amounts of hydrocarbons formed from fatty acids and intensity of ESR signals in bone fragments were measured. Very good correlation was found between the amount of hydrocarbons and the intensity of ESR signals. The amount of hydrocarbons (Cn-2:1), having 2 carbon atoms less than the original fatty acids and an additional double bond, was almost constant irrespective of the irradiation temperature. The amount of hydrocarbons (Cn-1:0), having 1 carbon atom less than the original fatty acids, increased as the irradiation temperature raised. As the ratio between corresponding fatty acids, the ratio between hydrocarbons (Cn-2:1) is a suitable index in the detection of the irradiation. On the contrary, the ratio of hydrocarbons from the same fatty acid, (Cn-2:1)/(Cn-1:0), varied according to the kind of fatty acid and irradiation temperature. It was found that under the irradiation temperature of -19 - 10degC, the intensity of ESR signals of bone is not affected by the irradiation temperature. (J.P.N.)

  18. Detection of irradiated chicken by hydrocarbon method and ESR method

    International Nuclear Information System (INIS)

    Chicken meat with bone was irradiated by gamma ray at - -19∼10degC, and both amount of hydrocarbons formed from fatty acids and intensity of ESR signals in bone fragments were measured. Very good correlation was found between the amount of hydrocarbons and the intensity of ESR signals. The amount of hydrocarbons (Cn-2 : 1), had 2 carbon atoms less than the original fatty acids and an additional double bond, was almost constant irrespective of the irradiation temperature. The amount of hydrocarbons (Cn-1: 0), had l carbon atom less than the original fatty acids, increased as the irradiation temperature raised. As the ratio between corresponding fatty acids, the ratio between hydrocarbons (Cn-2 : l) is a suitable index in the detection of the irradiation. On the contrary, the ratio of hydrocarbons from same fatty acid, (Cn-2 : 1)/(Cn-1 : 0), varied according to the kind of fatty acid and temperature used at the irradiation. It was found that under the irradiation temperature of -19∼10degC, intensity of ESR signals of bone is not affected by the irradiation temperature. (author)

  19. ESR dating technique applied to Pleistocene Corals (Barbados Island)

    International Nuclear Information System (INIS)

    In this work we applied the ESR (Electron Spin Resonance) dating technique to a coral coming from Barbados island. After a preliminary purification treatment, coral samples were milled and separated in different granulometry groups. Powder samples having granulometry values between 125 μm-250 μm and 250 μm-500 μm were irradiated at the Calliope60 Co radioisotope source (R.C. ENEA-Casaccia) at doses between 10-3300 Gγ and their radiation induced ESR signals were measured by a Bruker EMS1O4 spectrometer. The signal/noise ratio turned to be highest far the granulometry between 250 μm-500 μm and consequently the paleo-curve was constructed by using the ESR signals related to this granulometry value. The paleo-curve was fitted with the exponential growth function y = a - b · e-cx which well describes the behaviour of the curve also in the saturation region. Extrapolating the paleo-dose and knowing the annual dose (999±79 μGy/y) we calculated a coral age of 156±12 ky, which is in good agreement with results obtained on coral coming from the same region by other authors

  20. Acoustical Imaging

    CERN Document Server

    Litniewski, Jerzy; Kujawska, Tamara; 31st International Symposium on Acoustical Imaging

    2012-01-01

    The International Symposium on Acoustical Imaging is a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. This interdisciplinary Symposium has been taking place continuously since 1968. In the course of the years the proceedings volumes in the Acoustical Imaging Series have become a reference for cutting-edge research in the field. In 2011 the 31st International Symposium on Acoustical Imaging was held in Warsaw, Poland, April 10-13. Offering both a broad perspective on the state-of-the-art as well as  in-depth research contributions by the specialists in the field, this Volume 31 in the Series contains an excellent collection of papers in six major categories: Biological and Medical Imaging Physics and Mathematics of Acoustical Imaging Acoustic Microscopy Transducers and Arrays Nondestructive Evaluation and Industrial Applications Underwater Imaging

  1. Acoustic textiles

    CERN Document Server

    Nayak, Rajkishore

    2016-01-01

    This book highlights the manufacturing and applications of acoustic textiles in various industries. It also includes examples from different industries in which acoustic textiles can be used to absorb noise and help reduce the impact of noise at the workplace. Given the importance of noise reduction in the working environment in several industries, the book offers a valuable guide for companies, educators and researchers involved with acoustic materials.

  2. Frequency dependent power fluctuations: a feature of the ESR system or physical?

    Directory of Open Access Journals (Sweden)

    Y. Ogawa

    Full Text Available The k-dependence of the received power in high signal-to-noise ratio (SNR conditions, occurring for naturally enhanced ion-acoustic lines (NEIALs and for real satellites, is investigated by using the EISCAT Svalbard Radar (ESR, where the data are recorded in eight separate channels using different frequencies. For the real satellites we find large variations of the relative powers from event to event, which is probably due to a different number of pulses catching the satellite over the integration period. However, the large power difference remains unexpected in one case. Over short time scale (< 10 s the relative power difference seems to be highly stable. For most NEIAL events the differences between channels are within noise level. In a few cases variations of the relative power well above both the estimated and expected 1-sigma level occur over a signal preintegrated profile. We thus suggest that the frequency dependence of the power in NEIAL events has its origin in the scattering medium itself as the most plausible explanation.

    Key words: Ionosphere (auroral ionosphere; plasma waves and instabilities; instruments and techniques

  3. Radiation acoustics

    CERN Document Server

    Lyamshev, Leonid M

    2004-01-01

    Radiation acoustics is a developing field lying at the intersection of acoustics, high-energy physics, nuclear physics, and condensed matter physics. Radiation Acoustics is among the first books to address this promising field of study, and the first to collect all of the most significant results achieved since research in this area began in earnest in the 1970s.The book begins by reviewing the data on elementary particles, absorption of penetrating radiation in a substance, and the mechanisms of acoustic radiation excitation. The next seven chapters present a theoretical treatment of thermoradiation sound generation in condensed media under the action of modulated penetrating radiation and radiation pulses. The author explores particular features of the acoustic fields of moving thermoradiation sound sources, sound excitation by single high-energy particles, and the efficiency and optimal conditions of thermoradiation sound generation. Experimental results follow the theoretical discussions, and these clearl...

  4. ESR1 and EGF genetic variation in relation to breast cancer risk and survival

    OpenAIRE

    Einarsdóttir, Kristjana; Darabi, Hatef; Li, Yi; Low, Yen Ling; Li, Yu Qing; Bonnard, Carine; Sjölander, Arvid; Czene, Kamila; Wedrén, Sara; Liu, Edison T.; Hall, Per; Humphreys, Keith; Liu, Jianjun

    2008-01-01

    Introduction Oestrogen exposure is a central factor in the development of breast cancer. Oestrogen receptor alpha (ESR1) is the main mediator of oestrogen effect in breast epithelia and has also been shown to be activated by epidermal growth factor (EGF). We sought to determine if common genetic variation in the ESR1 and EGF genes affects breast cancer risk, tumour characteristics or breast cancer survival. Methods We genotyped 157 single nucleotide polymorphisms (SNPs) in ESR1 and 54 SNPs in...

  5. Electron spin resonance (ESR) spectroscopy applied to radiation dosimetry and other fields

    International Nuclear Information System (INIS)

    A short introduction to the theory and practice of ESR spectroscopy is given. ESR alanine dosimetry for low and high LET (linear energy transfer) ionising radiation is described, indicating its advantages over traditional methods. Problems arising in the therapy dose range (below 5 Gy), and possible future developments, are mentioned. The application of ESR to the radiation processing of materials and foodstuffs, to geological dating, biology, molecular chemistry and to medicine is discussed. Some examples of chemical analyses are also presented. (orig.)

  6. Alanine-ESR in vivo dosimetry: a feasibility study and possible applications

    International Nuclear Information System (INIS)

    A new alanine-ESR dosimeter has been developed at AERIAL in order to study its potential use in radiotherapy. Alanine-ESR results are compared with ion chamber for depth-dose measurements. A good concordance has been found between provisional dosimetry and absorbed dose during high dose rate and intra operative treatments. The results of the experiments indicate that alanine-ESR dosimetry is suited to check dose optimisation routines and seems to be a promising in vivo dosimetry technique. (Author)

  7. A study of the composite character of the ESR spectrum of alanine

    International Nuclear Information System (INIS)

    Both L and DL-alanine ESR powder spectra have been studied in the dose range of 1-106 Gy. By using Maximum Likelihood Common Factor Analysis (MLCFA), it has been demonstrated that the ESR spectrum of L-alanine is at least 3-fold composite over the whole dose range considered. For DL-alanine, in certain dose ranges only two ESR components could be detected. Possible consequences for the application and optimization of alanine dosimetry are discussed. (Author)

  8. Electron spin resonance (ESR) in multiferroic TbMnO3

    International Nuclear Information System (INIS)

    We report temperature dependent X-Band (ν∼9.4GHz) electron spin resonance (ESR) measurement in a single crystal of TbMnO3. A single Lorentzian ESR line with an isotropic g∼ 1.96 was observed for T>=120K up to 600K. The ESR signal is attributed to the Mn3+ ions in a insulator environment. For the three crystallographic axes the temperature dependence ESR linewidth shows a strong broadening as the temperature decreases due to the presence of short range magnetic correlations

  9. Detection of gamma-irradiated peanuts by ESR spectroscopy and GC analysis of hydrocarbons

    International Nuclear Information System (INIS)

    Peanuts were analyzed by electron spin resonance (ESR) spectroscopy and gas chromatography (GC) before and after gamma irradiation. Using European protocols, the validity and effectiveness of these two techniques were compared with regard to sample preparation, sample and solvent consumption and dose-response curves after irradiation. The results showed the possibility of using ESR and GC for distinguishing between irradiated and unirradiated peanuts. A radiation dose of 0.1 kGy could be detected by ESR but not by GC. The results also indicated that GC is an effective method for qualitative analysis of irradiated peanut, while ESR is suitable for the rapid detection of irradiated peanuts.

  10. Association with litter size of new polymorphisms on ESR1 and ESR2 genes in a Chinese-European pig line

    Directory of Open Access Journals (Sweden)

    Rodriguez Carmen

    2007-02-01

    Full Text Available Abstract The objective of this study was to search for polymorphisms in the coding region of the estrogen receptors 1 and 2 (ESR1 and ESR2 and to analyze the effects of these variants and the well known intronic ESR1 Pvu II polymorphism on litter size in a Chinese-European pig line. We identified five silent single nucleotide polymorphisms (SNP in the ESR1 cDNA: c.669T > C (exon 3, c.1227C > T (exon 5, c.1452C > T (exon 7, c.1665T > C and c.1755A > G (exon 8. One pair of these SNP (c.1665T > C and c.1755A > G co-segregated in the analyzed line, and the SNP c.669T > C showed the same segregation pattern as the Pvu II polymorphism. These polymorphisms were tested in this study, although the c.1452C > T SNP within exon 7 was not analyzed due to its low informativeness. In the ESR2 cDNA, one missense SNP was found within exon 5, which caused an amino acid substitution in the coded protein: "c.949G > A (p.Val317Met" and was tested on sow litter size. Information on 1622 litter records from 408 genotyped sows was analyzed to determine whether these SNP influenced the total number of piglets born (TNB or the number of born alive (NBA. The polymorphisms ESR1: [Pvu II; c.669T > C], ESR1: [c.1665T > C; c.1755A > G] and ESR2: c.949G > A showed no statistically significant association with litter size. However, the ESR1: c.1227T allele was significantly associated with TNB. The additive substitution effect was estimated to be 0.40 piglets born per litter (P

  11. Can ESR spectroscopy be used to detect irradiated food?

    International Nuclear Information System (INIS)

    The development of a test or tests for the detection of irradiated food would facilitate international trade in irradiated food and enhance consumer confidence in the existing control procedures. Over many years, extensive research programmes have been devoted to understanding the chemical changes which occur in irradiated foods and to establishing the effects of irradiation on the microbiological, organoleptic and nutritional quality of foods. Less effort has been directed towards the development of detection methods. The use of electron spin resonance (ESR) spectroscopy for the detection of irradiated food is being examined. (author)

  12. Pulse Dipolar ESR and Protein Superstructures and Function

    Science.gov (United States)

    Freed, Jack

    2014-03-01

    Pulse dipolar electron-spin resonance (PDS-ESR) has emerged as a powerful methodology for the study of protein structure and function. This technology, in the form of double quantum coherence (DQC) - ESR and double-electron-electron resonance (DEER) in conjunction with site-directed spin-labeling will be described. It enables the measurement of distances and their distributions in the range of 1-9 nm between pairs of spins labeled at two sites in the protein. Many biological objects can be studied: soluble and membrane proteins, protein complexes, etc. Many sample morphologies are possible: uniform, heterogeneous, etc. thereby permitting a variety of sample types: solutions, liposomes, micelles, bicelles. Concentrations from micromolar to tens of millimolar are amenable, requiring only small amounts of biomolecules. The distances are quite accurate, so a relatively small number of them are sufficient to reveal structures and functional details. Several examples will be shown. The first is defining the protein complexes that mediate bacterial chemotaxis, which is the process whereby cells modulate their flagella-driven motility in response to environmental cues. It relies on a complex sensory apparatus composed of transmembrane receptors, histidine kinases, and coupling proteins. PDS-based models have captured key architectural features of the receptor kinase arrays and the flagellar motor, and their changes in conformation and dynamics that accompany kinase activation and motor switching. Another example will be determining the conformational states and cycling of a membrane transporter, GltPh, which is a homotrimer, in its apo, substrate-bound, and inhibitor-bound, states in membrane vesicles providing insight into its energetics. In a third example the structureless (in solution) proteins alpha-synuclein and tau, which are important in Parkinson's disease and in neurodegeneration will be described and the structures they take on in contact with membranes will be

  13. ESR experiments on quaternary calcites and bones for dating purposes

    International Nuclear Information System (INIS)

    A series of experiments and measurements regarding sample preparation, peak intensity estimation, annealing, signal identification, dose determination and dose-rate estimation was carried out in order to explore the technique of ESR for dating speleothemes and bones. Anthropological remains from a cave were used for this study. The results indicate the existence of four peaks, two organic and two radiation induced ones. The bone samples were found to have absorbed large amounts of uranium from the environment making their dating impossible. A range of ages 20-45x103 years was calculated for the travertines of the cave. (author) 15 refs.; 10 figs

  14. ESR study on the photo polymerization of dental composites

    International Nuclear Information System (INIS)

    ESR (Electron Spin Resonance) spectra in X-band and at room temperature, of dental composites containing Bis-GMA type resin were obtained after irradiated wit conventional curing lamp of visible-light and laser light of red, green and blue colors. The blue light is the most suitable to produce methacrylate free radicals needed to its polymerization. However, Vickers hardness number determined in samples cured with conventional light indicated that their hardness number are equivalent to that obtained with blue light even producing less radicals, probably because conventional lamp generates more heat in the sample which helps its polymerization. Examining samples irradiated with green light, which is inadequate for usual practice by its lacking in energy, it has observed that this material has a striking ability to post cure by itself. It has concluded that the observation made by Ottaviani and collaborators, in a previous publication, that the time recommended by composite makers was insufficient, analyzing only ESR measurements, must be revised. (author)

  15. ESR/alanine dosimetry applied to radiation processing

    International Nuclear Information System (INIS)

    The radiation processing of food products is specified in terms of absorbed dose, and processing quality is assessed on the basis of absorbed dose measurements. The validity of process quality control is highly dependent on the quality of the measurements and associated instrumentation; in this respect, dosimetry calibration by an Organization with official status provides an essential guarantee of validity to the quality control steps taken. The Laboratoire de Metrologie des Rayonnements Ionisants (L.M.R.I.) is the primary standards and evaluation laboratory approved by the Bureau National de Metrologie (B.N.M.), which is the French National Bureau of Standards. The LMRI implements correlation procedures in response to the various requirements which arise in connection with high doses and doserates. Such procedures are mainly based on ESR/alanine spectrometry, a dosimetry technique ideally suited to that purpose. Dosemeter geometry and design are tailored to operating conditions. Photon dosemeters consist of a detector material in powder or compacted form, and a wall with thickness and chemical composition consistent with the application. Electron dosemeters have a detector core of compacted alanine with thickness down to a few tenths of a millimeter. The ESR/alanine dosimetry technique, developed at LMRI is a flexible, reliable and accurate tool which effectively meets the various requirements arising in the field of reference dosimetry, where high doses and doserates are involved. (author)

  16. Attempts at refining system parameters for ESR measurements in shellfish

    International Nuclear Information System (INIS)

    The evaluation of ESR spectra for various species of shellfish may pose problems in cases, where the radiation dose was low. Difficulties are added by unspecific interference signals from manganese that vary in intensity. As such variations were even observed between the samples analyzed during this multilateral study (Nephrops norvegicus), which are likely to have the same geographical origin, they are probably closely linked to the age and degree of calcification of the shell. In spite of those difficulties, an attempt was made to achieve a reliable distinction between irradiated and non-irradiated samples by gradually increasing the microwave rate and simultaneously diminishing the modulation amplitude. The results obtained cannot be regarded as being of general value, as each sample had its specific individual reactions. The adjustment of the measuring parameters did not basically improve the quality of the ESR signal. We take the view that false-negative results cannot always be excluded in cases of low-dose irradiation and high manganic contents. (orig./vhe)

  17. Phase transitions of natural corals monitored by ESR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Vongsavat, V. [Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Rajathevi, Bangkok 10400 (Thailand); Winotai, P. [Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Rajathevi, Bangkok 10400 (Thailand); Meejoo, S. [Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Rajathevi, Bangkok 10400 (Thailand)]. E-mail: scsmj@mahidol.ac.th

    2006-01-15

    The main purpose of this work is to present a systematic study of structure of marine exoskeletons, Acropora coral and its structural transformation upon heat treatments. The coralline sample was ground and characterized as powder throughout this work. Structural identifications of all samples have been confirmed using X-ray diffraction and IR spectroscopy. It was clearly found that the fresh specimen is made of aragonite, a common phase of the mineral CaCO{sub 3}. Thermal analyses, DSC and TGA were used to monitor structural and thermal decompositions and an irreversible solid-state phase transition from aragonite to calcite of the marine carbonate. Next, the coral powder was annealed at specific temperatures over the range 350-900 deg. C, and the effects of heat treatment on the structure of coralline samples were carefully studied by Rietveld refinement method. In addition, we have examined Mn{sup 2+} paramagnetic ions and free radicals present in the coral and changes of those upon heating by using ESR spectroscopy. The local environments of Mn{sup 2+} ions were verified from the calculated ESR spectra using appropriate spin Hamiltonian parameters, i.e. gyromagnetic tensor g , zero-field splitting D and hyperfine tensor A . This work reported structures and compositions as well as physical, chemical and thermal properties of the coralline material upon heat treatments qualitatively and quantitatively.

  18. Radiation-induced defects in magnesium lactate as ESR dosimeter

    CERN Document Server

    Hassan, G M; Takaki, S

    1999-01-01

    Magnesium lactate (Mg-lactate: (CH sub 3 CH(OH)COO) sub 2 Mg), magnesium lactate doped with lithium lactate (Mg(Li)-lactate) and nominal pure lithium lactate (CH sub 3 CH(OH)COOLi) doped with Mg-lactate (Li(Mg)-lactate) were irradiated by gamma-rays to study radicals for materials of radiation dosimeter with electron spin resonance (ESR). Quartet spectra were ascribed to lactate radicals in Mg-lactate and Li(Mg)-lactate with the spectroscopic splitting factors (g-factor) of 2.0032+-0.004 and 2.0029+-0.004 and the intensity ratio of 1:3:3:1 due to the hyperfine coupling constants of (A/g beta) of 1.92+-0.06 and 1.82+-0.06 mT, respectively. The response to gamma-ray dose and the thermal stability as well as the effect of UV-illumination have been studied to establish this material as an ESR dosimeter. The number of free radicals per 100 eV (G-value) was obtained to be 1.15+-0.32, 1.35+-0.35, 0.46+-0.14 and 0.78+-0.24 for Mg-lactate, Mg(Li)-lactate, Li-lactate and Lie(Mg)-lactate, respectively. Thermoluminescenc...

  19. Second interlaboratory-comparison project on ESR dating

    Energy Technology Data Exchange (ETDEWEB)

    Barabas, M.; Walther, R. (Akademie der Wissenschaften, Heidelberg (Germany). Inst. fuer Umweltphysik); Wieser, A. (Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany)); Radtke, U. (Duesseldorf Univ. (Germany). Geographisches Inst.); Gruen, R. (Research Lab. for Radiocarbon Dating, ANV, Canberra (Australia))

    An intercomparison project on ESR dating in which 14 ESR groups participated was initiated. Each group was provided with two samples of a coral powder, one of which (Sample A) was a fossil coral with a mass spectrometric determined U/Th age. Sample B was a recent coral, irradiated with a definite [gamma]-dose (checked by alanine dosimetry). In both cases the accumulated dose (AD) had to be determined (for sample A the U-content and age as well). Additionally, the chance of a calibration of [gamma]-sources by alanine dosimeters was offered. The results show that the [gamma]-source calibration is better then [+-] 5%, the mean value of the AD from sample A seems to agree with the expected AD but the mean AD value from sample B is overestimated, systematic errors occur due to the fitting procedure: the AD estimate depends on the maximum [gamma]-dose used for the irradiation curve, the AD determination including the smallest systematic error gives correct values for sample B but too low values for sample A which may be caused by fading of the signal g = 2.0006. (author).

  20. Predicted signatures of pulsed reconnection in ESR data

    Directory of Open Access Journals (Sweden)

    C. J. Davis

    Full Text Available Early in 1996, the latest of the European incoherent-scatter (EISCAT radars came into operation on the Svalbard islands. The EISCAT Svalbard Radar (ESR has been built in order to study the ionosphere in the northern polar cap and in particular, the dayside cusp. Conditions in the upper atmosphere in the cusp region are complex, with magnetosheath plasma cascading freely into the atmosphere along open magnetic field lines as a result of magnetic reconnection at the dayside magnetopause. A model has been developed to predict the effects of pulsed reconnection and the subsequent cusp precipitation in the ionosphere. Using this model we have successfully recreated some of the major features seen in photometer and satellite data within the cusp. In this paper, the work is extended to predict the signatures of pulsed reconnection in ESR data when the radar is pointed along the magnetic field. It is expected that enhancements in both electron concentration and electron temperature will be observed. Whether these enhancements are continuous in time or occur as a series of separate events is shown to depend critically on where the open/closed field-line boundary is with respect to the radar. This is shown to be particularly true when reconnection pulses are superposed on a steady background rate.

  1. ESR and Microwave Absorption in Boron Doped Diamond Single Crystals

    Science.gov (United States)

    Timms, Christopher

    2015-03-01

    Superconductivity has been reportedly found in boron-doped diamond. Most research to date has only studied superconductivity in polycrystalline and thin film boron-diamonds, as opposed to a single crystal. In fact, only one other group has examined a macro scale boron-doped diamond crystal. Our group has successfully grown large single crystals by using the High Temperature High Pressure method (HTHP) and observed a transition to metallic and superconducting states for high B concentrations. For the present, we are studying BDD crystal using Electron Spin Resonance. We conducted our ESR analysis over a range of temperatures (2K to 300K) and found several types of signals, proving the existence of charge carriers with spin 1/2 in BDD. Moreover, we have found that with increasing B concentrations, from n ~ 1018 cm-3 to n of over 1020 cm-3, the ESR signal changes from that of localized spins to the Dysonian shape of free carriers. The low magnetic field microwave absorption has also been studied in BDD samples at various B concentrations and the clear transition to superconducting state has been found below Tc that ranges from 2K to 4 K depending on concentration and quality of crystal. Sergey Polyakov, Victor Denisov, Vladimir Blank, Ray Baughman, Anvar Zakhidov.

  2. Room Acoustics

    Science.gov (United States)

    Kuttruff, Heinrich; Mommertz, Eckard

    The traditional task of room acoustics is to create or formulate conditions which ensure the best possible propagation of sound in a room from a sound source to a listener. Thus, objects of room acoustics are in particular assembly halls of all kinds, such as auditoria and lecture halls, conference rooms, theaters, concert halls or churches. Already at this point, it has to be pointed out that these conditions essentially depend on the question if speech or music should be transmitted; in the first case, the criterion for transmission quality is good speech intelligibility, in the other case, however, the success of room-acoustical efforts depends on other factors that cannot be quantified that easily, not least it also depends on the hearing habits of the listeners. In any case, absolutely "good acoustics" of a room do not exist.

  3. Acoustical Imaging

    CERN Document Server

    Akiyama, Iwaki

    2009-01-01

    The 29th International Symposium on Acoustical Imaging was held in Shonan Village, Kanagawa, Japan, April 15-18, 2007. This interdisciplinary Symposium has been taking place every two years since 1968 and forms a unique forum for advanced research, covering new technologies, developments, methods and theories in all areas of acoustics. In the course of the years the volumes in the Acoustical Imaging Series have developed and become well-known and appreciated reference works. Offering both a broad perspective on the state-of-the-art in the field as well as an in-depth look at its leading edge research, this Volume 29 in the Series contains again an excellent collection of seventy papers presented in nine major categories: Strain Imaging Biological and Medical Applications Acoustic Microscopy Non-Destructive Evaluation and Industrial Applications Components and Systems Geophysics and Underwater Imaging Physics and Mathematics Medical Image Analysis FDTD method and Other Numerical Simulations Audience Researcher...

  4. Battlefield acoustics

    CERN Document Server

    Damarla, Thyagaraju

    2015-01-01

    This book presents all aspects of situational awareness in a battlefield using acoustic signals. It starts by presenting the science behind understanding and interpretation of sound signals. The book then goes on to provide various signal processing techniques used in acoustics to find the direction of sound source, localize gunfire, track vehicles, and detect people. The necessary mathematical background and various classification and fusion techniques are presented. The book contains majority of the things one would need to process acoustic signals for all aspects of situational awareness in one location. The book also presents array theory, which is pivotal in finding the direction of arrival of acoustic signals. In addition, the book presents techniques to fuse the information from multiple homogeneous/heterogeneous sensors for better detection. MATLAB code is provided for majority of the real application, which is a valuable resource in not only understanding the theory but readers, can also use the code...

  5. Acoustics Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fisheries acoustics data are collected from more than 200 sea-days each year aboard the FRV DELAWARE II and FRV ALBATROSS IV (decommissioned) and the FSV Henry B....

  6. Erythrocyte sedimentation rate (ESR) measured by the Streck ESR-Auto Plus is higher than with the Sediplast Westergren method: a validation study.

    Science.gov (United States)

    Vennapusa, Bharathi; De La Cruz, Laura; Shah, Hemangini; Michalski, Veronica; Zhang, Qian-Yun

    2011-03-01

    The erythrocyte sedimentation rate (ESR) is a nonspecific indicator of disease activity and is often used by clinicians in assisting diagnosis and follow-up of many inflammatory disorders. The Westergren method is considered the standard method for measuring ESR. Recently, many automated instruments have become available to address laboratory safety and time efficiency. We validated the Streck ESR-Auto Plus instrument (Streck, Omaha, NE) using the Sediplast (Polymedco, Cortlandt Manor, NY) Westergren method as the reference method. Blood samples collected in 113 EDTA tubes were transferred into Sediplast vials and Streck high-altitude vacuum tubes for measuring the ESR. There was good correlation between the Sediplast and Streck methods (0.95) using Pearson correlation. The y-intercept was at 6.5 using linear regression, indicating systematic bias with a mean difference of 7.13 using the t test (P < .0001). We modified our reference ranges to rectify the systematic bias found during validation. PMID:21350092

  7. Improvement of the ESR detection of irradiated food containing cellulose employing a simple extraction method

    International Nuclear Information System (INIS)

    Fruit may be irradiated at rather low doses, below 1 kGy in combination treatments or for quarantine purposes. To improve the ESR detection sensitivity of irradiated fruit de Jesus et al. (Int. J. Food Sci. Technol. 34 (1999) 173.) proposed extracting the fruit pulp with 80% ethanol and measuring the residue with ESR using low power (0.25 mW) for detection of 'cellulosic' radicals. An improvement in ESR sensitivity using the extraction procedure could be confirmed in this paper for strawberries and papayas. In most cases, a radiation dose of 0.5 kGy could be detected in both fruits even after 2-3 weeks storage. In addition, some herbs and spices were also tested, but only for a few of them the ESR detection of the 'cellulosic' signal was improved by previous alcoholic extraction. As an alternative to ESR measurements, other detection methods like DNA Comet Assay and thermoluminescence were also tested

  8. Acoustic biosensors.

    Science.gov (United States)

    Fogel, Ronen; Limson, Janice; Seshia, Ashwin A

    2016-06-30

    Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors. PMID:27365040

  9. Luminescence and ESR Studies of CaS:Dy Phosphor

    Institute of Scientific and Technical Information of China (English)

    Vijay Singh; ZHU Jun-Jie; T.K.Gundu Rao; Manoj Tiwari; PAN Hong-Cheng

    2005-01-01

    @@ CaS phosphor activated with Dy ions is prepared by the solid-state diffusion method. The phosphor is characterized by x-ray powder diffraction, thermogravimetric analysis and photoluminescence. Defect centres formed in CaS:Dy are studied using the technique of electron spin resonance. The thermoluminescence glow curve shows peaks at around 117℃ and 345℃ . Irradiated CaS:Dy exhibits ESR lines due to defect centres. The thermal annealing behaviour of one of the defect centres appears to correlate with the TL peaks at 117℃ and 345℃.This centre is characterized by an isotropic g-value of 2.0035 and is assigned to an F+ centre.

  10. Characterization of structure and thermophysical properties of three ESR slags

    Science.gov (United States)

    Plotkowski, A.; deBarbadillo, J.; Krane, Matthew J. M.

    2016-07-01

    The structure and properties of electroslag remelting (ESR) slags were characterized. Slags samples of three compositions were obtained from industrial remelting processes at Special Metals Corporation and from casting in a laboratory vacuum induction melter. The structure of the slag samples was observed using optical and electron microscopy, and phases were identified and their relative amounts quantified using X-ray diffraction. Laser flash thermal diffusivity, density, and differential scanning calorimetry measurements for specific heat were performed to determine the bulk thermal conductivity of the samples. Sample porosity was measured as a function of depth using a serial sectioning technique, and a onedimensional computational model was developed to estimate the thermal conductivity of the fully dense slags. These results are discussed in context with previous studies, and opportunities for future research are identified. AFRL Case Number: 88ABW-2015-1871.

  11. The use of different methods for rapid determination of the ESR induces DAS28 misclassification in clinical practice.

    NARCIS (Netherlands)

    Maas, A. van der; Ende, C.H.M. van den; Eerd, J. van; Fransen, J.; Broeder, A. den

    2010-01-01

    OBJECTIVES: Monitoring of disease activity using DAS28 is more effective than routine RA care, but the ESR measurement is time consuming. Alternative rapid ESR determination methods can be used but effects on DAS28 classification are unknown. METHODS: Alternative rapid ESR methods, including the Sta

  12. Acoustic emission

    International Nuclear Information System (INIS)

    This paper is related to our activities on acoustic emission (A.E.). The work is made with different materials: metals and fibre reinforced plastics. At present, acoustic emission transducers are being developed for low and high temperature. A test to detect electrical discharges in electrical transformers was performed. Our experience in industrial tests to detect cracks or failures in tanks or tubes is also described. The use of A.E. for leak detection is considered. Works on pattern recognition of A.E. signals are also being performed. (Author)

  13. ESR technique for noninvasive way to quantify cyclodextrins effect on cell membranes

    Energy Technology Data Exchange (ETDEWEB)

    Grammenos, A., E-mail: A.Grammenos@ulg.ac.be [Laboratory of Biomedical Spectroscopy, Department of Physics, B5, University of Liege, Sart-Tilman (Belgium); Mouithys-Mickalad, A. [Center of Oxygen, Research and Development (CORD), Department of Chemistry, B6a, University of Liege, Sart-Tilman (Belgium); Guelluy, P.H.; Lismont, M. [Laboratory of Biomedical Spectroscopy, Department of Physics, B5, University of Liege, Sart-Tilman (Belgium); Piel, G. [Laboratory of Pharmaceutical Technology, Department of Pharmacy, CHU, B36, University of Liege, 1 Av. de l' Hopital (Belgium); Hoebeke, M. [Laboratory of Biomedical Spectroscopy, Department of Physics, B5, University of Liege, Sart-Tilman (Belgium)

    2010-07-30

    Research highlights: {yields} ESR: a new tool for cyclodextrins study on living cells. {yields} Cholesterol and phospholipid extraction by Rameb in a dose- and time-dependent way. {yields} Extracted phospholipids and cholesterol form stable aggregates. {yields} ESR spectra show that lipid rafts are damaged by Rameb. {yields} Quantification of the cholesterol extraction on cell membranes in a noninvasive way. -- Abstract: A new way to study the action of cyclodextrin was developed to quantify the damage caused on cell membrane and lipid bilayer. The Electron Spin Resonance (ESR) spectroscopy was used to study the action of Randomly methylated-beta-cyclodextrin (Rameb) on living cells (HCT-116). The relative anisotropy observed in ESR spectrum of nitroxide spin probe (5-DSA and cholestane) is directly related to the rotational mobility of the probe, which can be further correlated with the microviscosity. The use of ESR probes clearly shows a close correlation between cholesterol contained in cells and cellular membrane microviscosity. This study also demonstrates the Rameb ability to extract cholesterol and phospholipids in time- and dose-dependent ways. In addition, ESR spectra enabled to establish that cholesterol is extracted from lipid rafts to form stable aggregates. The present work supports that ESR is an easy, reproducible and noninvasive technique to study the effect of cyclodextrins on cell membranes.

  14. Estrogen Receptor Alpha (ESR1)-Dependent Regulation of the Mouse Oviductal Transcriptome.

    Science.gov (United States)

    Cerny, Katheryn L; Ribeiro, Rosanne A C; Jeoung, Myoungkun; Ko, CheMyong; Bridges, Phillip J

    2016-01-01

    Estrogen receptor-α (ESR1) is an important transcriptional regulator in the mammalian oviduct, however ESR1-dependent regulation of the transcriptome of this organ is not well defined, especially at the genomic level. The objective of this study was therefore to investigate estradiol- and ESR1-dependent regulation of the transcriptome of the oviduct using transgenic mice, both with (ESR1KO) and without (wild-type, WT) a global deletion of ESR1. Oviducts were collected from ESR1KO and WT littermates at 23 days of age, or ESR1KO and WT mice were treated with 5 IU PMSG to stimulate follicular development and the production of ovarian estradiol, and the oviducts collected 48 h later. RNA extracted from whole oviducts was hybridized to Affymetrix Genechip Mouse Genome 430-2.0 arrays (n = 3 arrays per genotype and treatment) or reverse transcribed to cDNA for analysis of the expression of selected mRNAs by real-time PCR. Following microarray analysis, a statistical two-way ANOVA and pairwise comparison (LSD test) revealed 2428 differentially expressed transcripts (DEG's, P < 0.01). Genotype affected the expression of 2215 genes, treatment (PMSG) affected the expression of 465 genes, and genotype x treatment affected the expression of 438 genes. With the goal of determining estradiol/ESR1-regulated function, gene ontology (GO) and bioinformatic pathway analyses were performed on DEG's in the oviducts of PMSG-treated ESR1KO versus PMSG-treated WT mice. Significantly enriched GO molecular function categories included binding and catalytic activity. Significantly enriched GO cellular component categories indicated the extracellular region. Significantly enriched GO biological process categories involved a single organism, modulation of a measurable attribute and developmental processes. Bioinformatic analysis revealed ESR1-regulation of the immune response within the oviduct as the primary canonical pathway. In summary, a transcriptomal profile of estradiol- and ESR1

  15. Estrogen Receptor Alpha (ESR1-Dependent Regulation of the Mouse Oviductal Transcriptome.

    Directory of Open Access Journals (Sweden)

    Katheryn L Cerny

    Full Text Available Estrogen receptor-α (ESR1 is an important transcriptional regulator in the mammalian oviduct, however ESR1-dependent regulation of the transcriptome of this organ is not well defined, especially at the genomic level. The objective of this study was therefore to investigate estradiol- and ESR1-dependent regulation of the transcriptome of the oviduct using transgenic mice, both with (ESR1KO and without (wild-type, WT a global deletion of ESR1. Oviducts were collected from ESR1KO and WT littermates at 23 days of age, or ESR1KO and WT mice were treated with 5 IU PMSG to stimulate follicular development and the production of ovarian estradiol, and the oviducts collected 48 h later. RNA extracted from whole oviducts was hybridized to Affymetrix Genechip Mouse Genome 430-2.0 arrays (n = 3 arrays per genotype and treatment or reverse transcribed to cDNA for analysis of the expression of selected mRNAs by real-time PCR. Following microarray analysis, a statistical two-way ANOVA and pairwise comparison (LSD test revealed 2428 differentially expressed transcripts (DEG's, P < 0.01. Genotype affected the expression of 2215 genes, treatment (PMSG affected the expression of 465 genes, and genotype x treatment affected the expression of 438 genes. With the goal of determining estradiol/ESR1-regulated function, gene ontology (GO and bioinformatic pathway analyses were performed on DEG's in the oviducts of PMSG-treated ESR1KO versus PMSG-treated WT mice. Significantly enriched GO molecular function categories included binding and catalytic activity. Significantly enriched GO cellular component categories indicated the extracellular region. Significantly enriched GO biological process categories involved a single organism, modulation of a measurable attribute and developmental processes. Bioinformatic analysis revealed ESR1-regulation of the immune response within the oviduct as the primary canonical pathway. In summary, a transcriptomal profile of estradiol- and

  16. ESR studies of high-energy phosphorus-ion implanted synthetic diamond crystals

    Energy Technology Data Exchange (ETDEWEB)

    Isoya, J. [University of Library and Information Science, Tsukuba, Ibaraki (Japan); Kanda, H.; Morita, Y.; Ohshima, T.

    1997-03-01

    Phosphorus is among potential n-type dopants in diamond. High pressure synthetic diamond crystals of type IIa implanted with high energy (9-18 MeV) phosphorus ions have been studied by using electron spin resonance (ESR) technique. The intensity and the linewidth of the ESR signal attributed to the dangling bond of the amorphous phase varied with the implantation dose, suggesting the nature of the amorphization varies with the dose. The ESR signals of point defects have been observed in the low dose as-implanted crystals and in the high dose crystals annealed at high temperature and at high pressure. (author)

  17. Flux properties in Bi-2212 single crystals studied by spin-probe ESR

    Science.gov (United States)

    Nishida, Akihiko; Taka, Chihiro; Yasuda, Takashi; Horai, Kazumi

    2000-07-01

    Flux properties in Bi 2Sr 2CaCu 2O 8+ x (Bi-2212) single crystals are studied by spin-probe method. ESR line widths of a very thin layer of DPPH free radical on the surface of the crystals begin to increase upon the superconducting transitions. At further low temperatures below irreversibility lines, distinct hysteresis is observed between ESR profiles for field increase and decrease. The resonance fields and intensities also indicate characteristic changes. Close correlations between ESR anomalies and vortex behaviors are discussed, comparing results of as-grown and optimally doped crystals.

  18. Spin Labeling ESR Investigation of Covalently Bound Residues in Soil

    Science.gov (United States)

    Aleksandrova, Olga; Steinhoff, Heinz-Juergen; Klasmeier, Joerg; Schulz, Marcus; Matthies, Michael

    2013-04-01

    Organic xenobiotic chemicals, such as pesticides, biocides and veterinary pharmaceuticals, interact with soil, which results in the simultaneous formations of metabolites, mineralization products, and bound or non-extractable residues (NER). Substances or metabolites with reactive functional groups, such as aniline or phenol, have a tendency to give a larger proportion of NER. Despite numerous studies on NER, the majority of their chemical structures is still unknown. Reversible sequestration and irreversible formation of NER were also observed for veterinary antibiotic pharmaceuticals, after their application to soil with and without manure. For this purpose, we hypothesized a key role of specific functional groups of soil contaminants, via which contaminants are covalently bound to soil constituents, and advance a method of spin labeling ESR investigation of reaction products using a membrane method. Spin labels (SL) represent chemically stable paramagnetic molecules used as molecular labels and molecular probes for testing the covalent binding, structural properties, and molecular mobility of different physical, chemical, and biological systems. In the case of covalent binding of SL, their ESR spectra become broadened. We used stable nitroxide radicals (NR) as SL. These radicals modeled organic chemical contaminants and differed only in one functional group. The paramagnetic SL 4-Amino Tempo (4-amino-2,2,6,6-tetramethyl-1-piperidinylox) differed from Tempo (2,2,6,6-Tetramethylpiperidinooxy) in a substituent at the para-position of the piperidine ring, whereas Aniline Tempo (1-Piperidinyloxy, 2,2,6,-tetramethyl, 6-Aniline) differed from Tempo in an Aniline substituting one CH3 functional group. Before experimental analysis, we tested temporal changes in the concentration of both NR incubated with soil and found that the life-times of them in soil exceeded 3 days. We contaminated and labeled soil samples with NR, adding to soil the aqueous solution, which already

  19. Predicting ESR Peaks in Titanium (III, Vanadium (IV and Copper (II Complexes of Halo Ligands by NMR, ESR and NQR Techniques: A DFT Study

    Directory of Open Access Journals (Sweden)

    Harminder Singh

    2015-09-01

    Full Text Available 15 halo (I≥1/2 complexes of Ti (III, V (IV and Cu (II each possessing one unpaired electron were studied using DFT implemented in ADF.2010.02. Aten, NQCC and h parameters of metal ions and ligands were obtained from ESR/EPR program while their σ and δ parameters were given by NMR/EPR program after optimization of complexes. Ligands having same values of these 5 parameters were spatially equivalent and, thus, would undergo same hyperfine interaction. Experimental determination of ESR lines in Cu (II complexes became erroneous because the presence of both the large Jahn-Teller effect and the high value of its spin-orbit coupling constant (λ Cu (II = -830 cm-1 affect the A ten parameter adversely. Cryoscopic conditions, generally required, in ESR experiments of Ti (IIIand V (IVcomplexes were difficult to obtain and cumbersome to maintain.

  20. Generalized Observables, Bell's Inequalities and Mixtures in the ESR Model for QM

    CERN Document Server

    Garola, Claudio

    2010-01-01

    The extended semantic realism (ESR) model proposes a new theoretical perspective which embodies the mathematical formalism of standard (Hilbert space) quantum mechanics (QM) into a noncontextual framework, reinterpreting quantum probabilities as conditional instead of absolute. We provide in this review an overall view on the present status of our research on this topic. We attain in a new, shortened way a mathematical representation of the generalized observables introduced by the ESR model and a generalization of the projection postulate of elementary QM. Basing on these results we prove that the Bell-Clauser-Horne-Shimony-Holt (BCHSH) inequality, a modified BCHSH inequality and quantum predictions hold together in the ESR model because they refer to different parts of the picture of the physical world supplied by the model. Then we show that a new mathematical representation of mixtures must be introduced in the ESR model which does not coincide with the standard representation in QM and avoids some deep p...

  1. Identification of irradiated sage tea (Salvia officinalis L.) by ESR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tepe Cam, Semra, E-mail: stepe06@gmail.co [Gazi University, Faculty of Medicine, Biophysics Department, 06500 Besevler, Ankara (Turkey); Engin, Birol [Turkish Atomic Energy Authority, Saraykoey Nuclear Research and Training Center, 06983 Ankara (Turkey)

    2010-04-15

    The use of electron spin resonance (ESR) spectroscopy to accurately distinguish irradiated from unirradiated sage tea was examined. Before irradiation, sage tea samples exhibit one asymmetric singlet ESR signal centered at g=2.0037. Besides this central signal, two weak satellite signals situated about 3 mT left and right to it in radiation-induced spectra. Irradiation with increasing doses caused a significant increase in radiation-induced ESR signal intensity at g=2.0265 (the left satellite signal) and this increase was found to be explained by a polynomial varying function. The stability of that radiation-induced ESR signal at room temperature was studied over a storage period of 9 months. Also, the kinetic of signal at g=2.0265 was studied in detail over a temperature range 313-353 K by annealing samples at different temperatures for various times.

  2. Identification of irradiated sage tea ( Salvia officinalis L.) by ESR spectroscopy

    Science.gov (United States)

    Tepe Çam, Semra; Engin, Birol

    2010-04-01

    The use of electron spin resonance (ESR) spectroscopy to accurately distinguish irradiated from unirradiated sage tea was examined. Before irradiation, sage tea samples exhibit one asymmetric singlet ESR signal centered at g=2.0037. Besides this central signal, two weak satellite signals situated about 3 mT left and right to it in radiation-induced spectra. Irradiation with increasing doses caused a significant increase in radiation-induced ESR signal intensity at g=2.0265 (the left satellite signal) and this increase was found to be explained by a polynomial varying function. The stability of that radiation-induced ESR signal at room temperature was studied over a storage period of 9 months. Also, the kinetic of signal at g=2.0265 was studied in detail over a temperature range 313-353 K by annealing samples at different temperatures for various times.

  3. Identification of irradiated sage tea (Salvia officinalis L.) by ESR spectroscopy

    International Nuclear Information System (INIS)

    The use of electron spin resonance (ESR) spectroscopy to accurately distinguish irradiated from unirradiated sage tea was examined. Before irradiation, sage tea samples exhibit one asymmetric singlet ESR signal centered at g=2.0037. Besides this central signal, two weak satellite signals situated about 3 mT left and right to it in radiation-induced spectra. Irradiation with increasing doses caused a significant increase in radiation-induced ESR signal intensity at g=2.0265 (the left satellite signal) and this increase was found to be explained by a polynomial varying function. The stability of that radiation-induced ESR signal at room temperature was studied over a storage period of 9 months. Also, the kinetic of signal at g=2.0265 was studied in detail over a temperature range 313-353 K by annealing samples at different temperatures for various times.

  4. Combined TL and 10B-alanine ESR dosimetry for BNCT.

    Science.gov (United States)

    Bartolotta, A; D'Oca, M C; Lo Giudice, B; Brai, M; Borio, R; Forini, N; Salvadori, P; Manera, S

    2004-01-01

    The dosimetric technique described in this paper is based on electron spin resonance (ESR) detectors using an alanine-boric compound acid enriched with (10)B, and beryllium oxide thermoluminescent (TL) detectors; with this combined dosimetry, it is possible to discriminate the doses due to thermal neutrons and gamma radiation in a mixed field. Irradiations were carried out inside the thermal column of a TRIGA MARK II water-pool-type research nuclear reactor, also used for Boron Neutron Capture therapy (BNCT) applications, with thermal neutron fluence from 10(9) to 10(14) nth cm(-2). The ESR dosemeters using the alanine-boron compound indicated ESR signals about 30-fold stronger than those using only alanine. Moreover, a negligible correction for the gamma contribution, measured with TL detectors, almost insensitive to thermal neutrons, was necessary. Therefore, a simultaneous analysis of our TL and ESR detectors allows discrimination between thermal neutron and gamma doses, as required in BNCT. PMID:15353720

  5. Test 1 analyser for determination of ESR. 1. Practical evaluation and comparison with the Westergren technique

    NARCIS (Netherlands)

    M.R. Hardeman; M. Levitus; A. Pelliccia; A.A. Bouman

    2010-01-01

    Background: Various modifications of the Erythrocyte Sedimentation Rate (ESR) determination have been suggested since the original Westergren procedure that has been adopted as the gold standard by the International Council for Standardization in Haematology (ICSH). Recently, an automated method, (A

  6. The ESR dosimetric features of strontium sulfate and temperature effects on radiation-induced signals

    Science.gov (United States)

    Acar, Ali Osman; Polat, Mustafa; Aydin, Talat; Aydaş, Canan

    2016-06-01

    In the present work, the ESR dosimetric potential of strontium sulfate has been investigated in the radiation dose range of 1-100 Gy. It does not exhibit any ESR signal before irradiation. However, irradiation produced three intensive resonance signals (A, B and C) which increase linearly in the studied dose range. Variable temperature study showed that all ESR signals were found to decrease significantly at temperatures higher than 340 K. Kinetic studies performed at high temperatures showed that at least two distinct radical species with the activation energy values of 42.8±3.6 and 88.2±5.8 kJ/mol, respectively, contributed to the ESR signal B.

  7. ESR investigation of L-α-alanine and sucrose radicals produced by heavy-ion irradiation

    International Nuclear Information System (INIS)

    We investigated sucrose and L-α-alanine radicals produced by heavy ion irradiation with various LETs (linear energy transfer). The impact of the heavy ions on the samples produced stable free radicals, which were analyzed by ESR (electron spin resonance). The obtained spectral patterns were the same as those for carbon (C), neon (Ne), and silicon (Si) ion irradiations. The absorbed dose dependences for the irradiated sucrose and alanine samples were examined. The ESR response has a linear relation with the absorbed dose for both compounds. In addition, the total spin concentration obtained by heavy-ion irradiation correlated logarithmically with the LET. Let Qualitative ESR analyses showed that the production of sucrose and alanine radical depended on both different particle irradiation and the LET under the same dose. Thus, the present ESR results imply that sucrose together with L-α-alanine can be used to investigate radical production processes induced by ionizing particles. (author)

  8. ESR spectrometric characterization of the methyl viologen dosimeter in poly(vinyl alcohol) film

    Science.gov (United States)

    Nishimoto, Sei-Ichi; Ye, Mu; Lu, Yiqun; Kawamura, Takashi; Kagiya, Tsutomu

    A dosimeter of poly(vinyl alcohol) (PVA) film containing methyl viologen dichloride (MV 2+ (Cl -) 2) was characterized by means of ESR and u.v. spectrometries. γ-irradiation of the MV 2+-PVA dosimeter induced one-electron reduction of MV 2+· to thecation radical (MV +), thus giving rise to blue coloration. The resulting MV +· showed an ESR signal with a g-factor of 2.0031. The yield of MV +· at a given radiation dose was estimated from duplicate integral of the ESR first-derivative spectra by reference to 1,1'-diphenyl-2-picrylhydrazyl (DPPH). The yield of MV +· thus estimated increased linearly with increasing the radiation dose up to about 1.4 Mrad. The ESR spectrometry of MV +· showed a linear correlation with the u.v. spectrometric method reported previously.

  9. ESR-Tree: a dynamic index for multi-dimensional objects%ESR-Tree:一种多维对象的动态索引方法

    Institute of Scientific and Technical Information of China (English)

    徐焕; 林坤辉

    2005-01-01

    在研究SR-tree(Sphere/Rectangle-tree)和X-tree(eXtended node tree)的结构与性能的基础上,针对SR-tree分裂算法的不足,改进了分裂算法,结合两者的优点,设计了一种新的多维索引结构ESR-tree(Extended SR-tree).实验表明,随着数据量和维数的增多,ESR-tree的性能要优于SR-tree和X-tree.

  10. Retracted: Impact of polymorphisms in the oestrogen receptors alpha and beta (ESR1, ESR2) genes on risk of vasculogenic erectile dysfunction.

    Science.gov (United States)

    2014-01-01

    The above article from Andrology, 'Impact of polymorphisms in the oestrogen receptors alpha and beta (ESR1, ESR2) genes on risk of vasculogenic erectile dysfunction' by M. R. Safarinejad, A. Taghva, N. Shafiei and S. Safarinejad published online on 20 May 2013 in Wiley Online Library has been retracted by agreement between the journal Editors-in-Chief, Douglas Carrell and Ewa Rajpert-De Meyts and John Wiley and Sons Ltd. The retraction has been decided due to failure by the lead author to verify the data contained in the study, and to provide evidence of the role of co-authors and their institutional affiliations.

  11. Nitrogen addition using a gas blow in an ESR process

    Science.gov (United States)

    Yamamoto, S.; Momoi, Y.; Kajikawa, K.

    2016-07-01

    A new nitrogen method for adding in an ESR process using nitrogen gas blown in through the electrode was investigated. Nitrogen gas blown through a center bore of the electrode enabled contact between the nitrogen gas and the molten steel directly underneath the electrode tip. A ɸ 145mm diameter, laboratory-sized PESR furnace was used for the study on the reaction kinetics. Also, we carried out a water-model experiment in order to check the injection depth of the gas blown in the slag. The water model showed that the gas did not reach the upper surface of the molten metal and flowed on the bottom surface of the electrode only. An EPMA was carried out for a droplet remaining on the tip of the electrode after melting. The molten steel from the tip of the electrode shows that nitrogen gas absorption occurred at the tip of the electrode. The mass transfer coefficient was around 1.0x10-2 cm/sec in the system. This value is almost the same as the coefficient at the molten steel free surface.

  12. Antioxidant Capacity of Cultured Mammalian Cells Estimated by ESR Method

    Directory of Open Access Journals (Sweden)

    Tamar Kartvelishvili

    2004-01-01

    Full Text Available In the present study, the antioxidant capacity against hydrogen peroxide (H2O2, one of the stress-inducing agents, was investigated in two distinct cell lines: L-41 (human epithelial-like cells and HLF (human diploid lung fibroblasts, which differ in tissue origin, life span in culture, proliferate activity, and special enzyme system activity. The cell antioxidant capacity against H2O2 was estimated by the electron spin resonance (ESR spin-trapping technique in the Fenton reaction system via Fe+2 ion action with H2O2 resulting in hydroxyl radical generation. The effects of catalase inhibitors, such as sodium azide and 3-amino-1,2,4-triazole, on the antioxidant capacity of cells were tested. Based on our observation, it can be concluded that the defensive capacity of cells against H2O2 depends on the ratio between catalase/GPx/SOD and H2O2, especially at high-stress situations, and the intracellular balance of these enzymes are more important than the influence of the single component.

  13. The influence of measurement and storage conditions on alanine ESR dosimeters

    International Nuclear Information System (INIS)

    Alanine has several desirable properties as an ESR dosemeter e.g. tissue equivalence, low fading and an approximately linear response for doses up to 10 kGy. This work reports on a simple system to produce the alanine dosemeter, the signal intensity for a range of doses and energies, and the effect of the air humidity and the spectrometer settings on the ESR signal. (Author)

  14. ESR and cathodoluminescence studies of radiation defects in clays and quartz fromsome U deposits

    OpenAIRE

    ブランディーヌ; 小室 光世; 中嶋, 悟; 永野 哲志; 正木 信行; 林 久人

    1992-01-01

    Rock samples from different world U deposits mainly in sedimentary rocks have been studied by Electron Spin Resonancc (ESR) spectroscopy and Cathodoluminescence (CL) measurement in order to characterize radiation damage centers in clays and quartz. The presence of kaolinite-like radiation centers ill ESR spectra in some of the samples containing kaolin group minerals suggests that this type of radiation damages can be used as an indicator of U behavior during supergene and hydrothermal altera...

  15. Microwave frequency modulation in continuous-wave far-infrared ESR utilizing a quasioptical reflection bridge

    OpenAIRE

    Nafradi, Balint; Gaal, Richard; Feher, Titusz; Forro, Laszlo

    2008-01-01

    We report the development of the frequency-modulation (FM) method for measuring electron spin resonance (ESR) absorption in the 210-420 GHz frequency range. We demonstrate that using a high-frequency ESR spectrometer without resonating microwave components enables us to overcome technical difficulties associated with the FM method due to nonlinear microwave-elements, without sacrificing spectrometer performance. FM was achieved by modulating the reference oscillator of a 13 GHz Phase Locked D...

  16. Chemical origin of the native ESR signals in thermally treated enamel and dentin

    International Nuclear Information System (INIS)

    Heating, crushing and exposure of dental enamel to sunlight and UV radiation can introduce paramagnetic signals similar to those following exposure to ionizing radiation. The objective of this work is to use infrared and electron spin resonance (ESR) spectra to study thermally treated enamel and dentin, and identify the chemical radical or mechanisms that produce these ambiguous ESR signals. Non-irradiated bovine teeth were used. ESR spectroscopy was performed in the X band and the infrared spectroscopy was performed on a FTIR spectrometer operating between 4000 cm-1 and 400 cm-1. The results show ESR signals in dentin heated at temperatures between 100 deg. C and 1000 deg. C and in enamel heated at temperatures ranging from 250 deg. C to 1000 deg. C. The ESR signal formed after heat treatment below 400 deg. C could be assigned to degradation products of the organic material, while the ESR signals that predominate in tissues heated between 500 deg. C and 900 deg. C show a maximum amplitude at 750 deg. C and could be assigned to the cyanate ion (NCO-)

  17. Diffusion studies on permeable nitroxyl spin probes through bilayer lipid membranes: A low frequency ESR study

    Energy Technology Data Exchange (ETDEWEB)

    Meenakumari, V.; Benial, A. Milton Franklin, E-mail: miltonfranklin@yahoo.com [Department of Physics, NMSSVN College, Nagamalai, Madurai-625019, Tamilnadu (India); Utsumi, Hideo; Ichikawa, Kazuhiro; Yamada, Ken-ichi [Department of Bio-functional Science, Kyushu University, Fukuoka (Japan); Hyodo, Fuminori [Innovation Center for Medical Redox Navigation, Kyushu University, Fukuoka (Japan); Jawahar, A. [Department of Chemistry, NMSSVN College, Nagamalai, Madurai-625019, Tamilnadu (India)

    2015-06-24

    Electron spin resonance (ESR) studies were carried out for permeable 2mM {sup 14}N-labeled deutrated 3 Methoxy carbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl (MC-PROXYL) in pure water and 1mM, 2mM, 3mM, 4mM concentration of 14N-labeled deutrated MC-PROXYL in 400mM concentration of liposomal solution by using a 300 MHz ESR spectrometer. The ESR parameters such as linewidth, hyperfine coupling constant, g-factor, partition parameter and permeability were reported for these samples. The line broadening was observed for the nitroxyl spin probe in the liposomal solution. The line broadening indicates that the high viscous nature of the liposomal solution. The partition parameter and permeability values indicate the maximum diffusion of nitroxyl spin probes in the bilayer lipid membranes at 2 mM concentration of nitroxyl radical. This study illustrates that ESR can be used to differentiate between the intra and extra- membrane water by loading the liposome vesicles with a lipid-permeable nitroxyl spin probe. From the ESR results, the spin probe concentration was optimized as 2mM in liposomal solution for ESR phantom studies/imaging, invivo and invitro experiments.

  18. Evolution of the Kondo state of YbRh2Si2 probed by high field ESR

    OpenAIRE

    Schaufuß, U.; KATAEV V.; Zvyagin, A. A.; Büchner, B.; Sichelschmidt, J.; Wykhoff, J.; Krellner, C.; Geibel, C.; Steglich, F.

    2008-01-01

    An electron spin resonance (ESR) study of the heavy fermion compound YbRh2Si2 for fields up to ~ 8 T reveals a strongly anisotropic signal below the single ion Kondo temperature T_K ~ 25 K. A remarkable similarity between the T-dependence of the ESR parameters and that of the specific heat and the 29Si nuclear magnetic resonance data gives evidence that the ESR response is given by heavy fermions which are formed below T_K and that ESR properties are determined by their field dependent mass a...

  19. Comprehensive genetic assessment of the ESR1 locus identifies a risk region for endometrial cancer.

    Science.gov (United States)

    O'Mara, Tracy A; Glubb, Dylan M; Painter, Jodie N; Cheng, Timothy; Dennis, Joe; Attia, John; Holliday, Elizabeth G; McEvoy, Mark; Scott, Rodney J; Ashton, Katie; Proietto, Tony; Otton, Geoffrey; Shah, Mitul; Ahmed, Shahana; Healey, Catherine S; Gorman, Maggie; Martin, Lynn; Hodgson, Shirley; Fasching, Peter A; Hein, Alexander; Beckmann, Matthias W; Ekici, Arif B; Hall, Per; Czene, Kamila; Darabi, Hatef; Li, Jingmei; Dürst, Matthias; Runnebaum, Ingo; Hillemanns, Peter; Dörk, Thilo; Lambrechts, Diether; Depreeuw, Jeroen; Annibali, Daniela; Amant, Frederic; Zhao, Hui; Goode, Ellen L; Dowdy, Sean C; Fridley, Brooke L; Winham, Stacey J; Salvesen, Helga B; Njølstad, Tormund S; Trovik, Jone; Werner, Henrica M J; Tham, Emma; Liu, Tao; Mints, Miriam; Bolla, Manjeet K; Michailidou, Kyriaki; Tyrer, Jonathan P; Wang, Qin; Hopper, John L; Peto, Julian; Swerdlow, Anthony J; Burwinkel, Barbara; Brenner, Hermann; Meindl, Alfons; Brauch, Hiltrud; Lindblom, Annika; Chang-Claude, Jenny; Couch, Fergus J; Giles, Graham G; Kristensen, Vessela N; Cox, Angela; Pharoah, Paul D P; Dunning, Alison M; Tomlinson, Ian; Easton, Douglas F; Thompson, Deborah J; Spurdle, Amanda B

    2015-10-01

    Excessive exposure to estrogen is a well-established risk factor for endometrial cancer (EC), particularly for cancers of endometrioid histology. The physiological function of estrogen is primarily mediated by estrogen receptor alpha, encoded by ESR1. Consequently, several studies have investigated whether variation at the ESR1 locus is associated with risk of EC, with conflicting results. We performed comprehensive fine-mapping analyses of 3633 genotyped and imputed single nucleotide polymorphisms (SNPs) in 6607 EC cases and 37 925 controls. There was evidence of an EC risk signal located at a potential alternative promoter of the ESR1 gene (lead SNP rs79575945, P=1.86×10(-5)), which was stronger for cancers of endometrioid subtype (P=3.76×10(-6)). Bioinformatic analysis suggests that this risk signal is in a functionally important region targeting ESR1, and eQTL analysis found that rs79575945 was associated with expression of SYNE1, a neighbouring gene. In summary, we have identified a single EC risk signal located at ESR1, at study-wide significance. Given SNPs located at this locus have been associated with risk for breast cancer, also a hormonally driven cancer, this study adds weight to the rationale for performing informed candidate fine-scale genetic studies across cancer types. PMID:26330482

  20. ESR investigation of L-α-alanine and sucrose radicals produced by heavy-ion irradiation

    International Nuclear Information System (INIS)

    We investigated sucrose and L-α-alanine radicals produced by heavy (particle) ion irradiation with various LETs (linear energy transfer). The impact of the heavy ions on the samples produced stable free radicals, which were analyzed by ESR (electron spin resonance). Identical spectra were measured after one year. The obtained spectral patterns were the same as those for helium (He), carbon (C), and neon (Ne) ions irradiation. The absorbed dose dependences for the irradiated sucrose and alanine samples were examined. The ESR response has a linear relation with the absorbed dose. The ESR response at 60 Gy was slightly lower than a linear line for sucrose; however, the response showed good linearity for the alanine. In addition, the total spin concentration obtained by heavy-ion irradiation correlated logarithmically with the LET. Qualitative ESR analyse showed that the production of sucrose and alanine radicals depended on both different particle irradiation and the LET under the same dose. Thus, the present ESR results imply that sucrose together with L-α-alanine can be used to monitor LET as well as the number of ionizing particle for the production of stable free radicals. (author)

  1. Dating of aragonite and dolomite from Devil's cave - SP, by dosimetric thermoluminescent method (DTL) and ESR

    International Nuclear Information System (INIS)

    We have investigated TL (Thermoluminescence) and ESR (electron spin resonance) properties of aragonite and dolomite found at ''Caverna do Diabo (Devil's cave)'' in the state of Sao Paulo to determine the ages of these geological materials. The aragonite, which is not a thermoluminescent material, shows one ESR signal whit g = 2.003. We obtained the age of 1.1 x 105 years and the growth rate of 1 μ m/year by the sample calibration with additional Y irradiation. The dolomite gives a TL glow curve with three distinct peaks at 261, 334 and 395 0C. We found that the fit for the TL glow curve to second-order kinetics can be considerered as very acceptable. Using the second TL peak we obtained the age of 9.4 x 10 5 years and the compatible values of the activation energy (1.90 ± 0,07 eV) by the following methods: Hyperbolic heating, isothermal decay and fractional glow technique. We observed many ESR absorption signals in the dolomite. Three principal signal com g = 2.002, 2.003 and 2.005 were studied. We found that the first and second ESR signals were atributed to the CO2- and/or CO33- centers and the last to the CO3- centers, and observed that the first ESR signal might related with the second TL peak and the TL sensitivity were associated with the concentration of Mn2+

  2. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available Educational Video Home What is an AN What is an Acoustic Neuroma? Identifying an AN Symptoms Acoustic Neuroma Keywords Educational Video ... for pre- and post-treatment acoustic neuroma patients. Home What is an AN What is an Acoustic ...

  3. Acoustic cryocooler

    Science.gov (United States)

    Swift, Gregory W.; Martin, Richard A.; Radenbaugh, Ray

    1990-01-01

    An acoustic cryocooler with no moving parts is formed from a thermoacoustic driver (TAD) driving a pulse tube refrigerator (PTR) through a standing wave tube. Thermoacoustic elements in the TAD are spaced apart a distance effective to accommodate the increased thermal penetration length arising from the relatively low TAD operating frequency in the range of 15-60 Hz. At these low operating frequencies, a long tube is required to support the standing wave. The tube may be coiled to reduce the overall length of the cryocooler. One or two PTR's are located on the standing wave tube adjacent antinodes in the standing wave to be driven by the standing wave pressure oscillations. It is predicted that a heat input of 1000 W at 1000 K will maintian a cooling load of 5 W at 80 K.

  4. Acoustic telemetry.

    Energy Technology Data Exchange (ETDEWEB)

    Drumheller, Douglas Schaeffer; Kuszmaul, Scott S.

    2003-08-01

    Broadcasting messages through the earth is a daunting task. Indeed, broadcasting a normal telephone conversion through the earth by wireless means is impossible with todays technology. Most of us don't care, but some do. Industries that drill into the earth need wireless communication to broadcast navigation parameters. This allows them to steer their drill bits. They also need information about the natural formation that they are drilling. Measurements of parameters such as pressure, temperature, and gamma radiation levels can tell them if they have found a valuable resource such as a geothermal reservoir or a stratum bearing natural gas. Wireless communication methods are available to the drilling industry. Information is broadcast via either pressure waves in the drilling fluid or electromagnetic waves in the earth and well tubing. Data transmission can only travel one way at rates around a few baud. Given that normal Internet telephone modems operate near 20,000 baud, these data rates are truly very slow. Moreover, communication is often interrupted or permanently blocked by drilling conditions or natural formation properties. Here we describe a tool that communicates with stress waves traveling through the steel drill pipe and production tubing in the well. It's based on an old idea called Acoustic Telemetry. But what we present here is more than an idea. This tool exists, it's drilled several wells, and it works. Currently, it's the first and only acoustic telemetry tool that can withstand the drilling environment. It broadcasts one way over a limited range at much faster rates than existing methods, but we also know how build a system that can communicate both up and down wells of indefinite length.

  5. Use of acoustic vortices in acoustic levitation

    DEFF Research Database (Denmark)

    Cutanda Henriquez, Vicente; Santillan, Arturo Orozco; Juhl, Peter Møller

    2009-01-01

    Acoustic fields are known to exert forces on the surfaces of objects. These forces are noticeable if the sound pressure is sufficiently high. Two phenomena where acoustic forces are relevant are: i) acoustic levitation, where strong standing waves can hold small objects at certain positions......, counterbalancing their weight, and ii) acoustic vortices, spinning sound fields that can impinge angular momentum and cause rotation of objects. In this contribution, both force-creating sound fields are studied by means of numerical simulations. The Boundary Element Method is employed to this end. The simulation...... of acoustical vortices uses an efficient numerical implementation based on the superposition of two orthogonal sound fields with a delay of 90° between them. It is shown that acoustic levitation and the use of acoustic vortices can be combined to manipulate objects in an efficient and controlled manner without...

  6. ESR of copper and iron complexes with antitumor and cytotoxic properties

    Energy Technology Data Exchange (ETDEWEB)

    Antholine, W.E.; Kalyanaraman, B.; Petering, D.H.

    1985-12-01

    The relatively few iron and copper metal complexes which have been examined in cells and tissues for their redox properties, radical generation properties, and antitumor activity are discussed for studies which utilized electron spin resonance spectroscopy (ESR). A common property of a number of metal complexes, which include bleomycin, adriamycin, and thiosemicarbazones described in this review, is that they are readily reduced by thiol compounds and oxidized by oxygen or reduced species of oxygen to produce radicals. Structural features of these reactions are identified by ESR spectroscopy in model systems and often in cells. Furthermore, ESR spectroscopy has been most useful to probe the environment of the complexes in cells and to measure the rate of reduction of their oxidized forms. As a result of these studies, it is anticipated that more attention will be given to the exploration of redox-active metal complexes as drugs. 95 references.

  7. Influence of Electrolyte on ESR of Medium Voltage Wet Tantalum Capacitors

    Institute of Scientific and Technical Information of China (English)

    刘仲娥; 宋金荣; 陈晓静; 李忆莲; 桂娟

    2004-01-01

    In this paper, the influence of working electrolyte on high-frequency electrical performance of wet tantalum capacitors is studied. Emphasis is especially put on the study of the contribution of depolariser in reducing Equivalent Series Resistance(ESR). According to the theory of depolarization in electrochemistry and the theory of cathode capacitance of electrolytic capacitor, different kinds of depolarisers are added separately into the foregone electrolyte. Then capacitors are assembled with tantalum cores dipped with the compounded electrolytes. The best depolariser and its concentration in the whole electrolyte could be selected according to the test results of the capacitance and ESR of the capacitors. The results of our experiment show that depolariser Fe2(SO4)3 used in working electrolyte of 100 V/100 μF wet tantalum capacitors can help to obtain lower ESR and higher capacitance at frequency from 0.1 kHz to 100 kHz.

  8. ESR Dosimetry Below 1 Gy, in X-Ray Irradiated Tooth Enamel

    International Nuclear Information System (INIS)

    Tooth enamel, extracted from molars, was irradiated with 66keV X-rays, with doses up to 1Gy.The preparation of the powder samples is described, as well as the protocol for the acquisition and processing of the spectra.The radiation induced paramagnetism is measured, at room temperature, by ESR Spectroscopy.The ESR spectra is well described considering two paramagnetic species, with magnetic moments (in units of Bohr magnetons) g=2,0041, and g1=2,0018, g2=1,9972.The ESR data (peak-to-peak amplitude per mg, hpp/mg, vs dose D), for doses 0Gy2 =0,996) with the linear expression: [hpp/mg] = -0,2( 0,4)+14,9(0,5). D [Gy].The result supports the growing confidence in the use of this material, and method, in Retrospective Dosimetry

  9. ESR Spectrometer as a Possible Tool for Rapid Analysis of Cane Sugar Purity

    Institute of Scientific and Technical Information of China (English)

    Kheamrutai Thamaphat; Pichet Limsuwan; Siwaporn Meejoo

    2007-01-01

    A method for quantitative/qualitative determination of eane sugar purity by ESR is devised.Relined sugar,plantation white sugar.soft brown sugar and raw sugar are used as samples in this work.The sucrose radical is produced by pulverization of sugar and it increases as the particle size decreases.Based on pulverization-induced sucrose radical.EsR study demonstrates the effects of sugar purity on characteristic of ESR spectrum.The relationshjp between the sucrose contents and peak area under the ESR spectrum is manifested.It is found that the peak area or sucrose radical concentration increases linearly With the increase of sucrose content.Using the linear regression method.the Sucrose amount can be revealed.This approach is a promising fast and accurate method for sugar purity analysis.

  10. Construction of an ESR-STM for Single Molecular Based Magnets anchored at Surfaces

    CERN Document Server

    Messina, Paul C; Lenci, L; Prato, S; Pittana, P; Gatteschi, Dante; Messina, Paolo; Sigalotti, Paolo; Lenci, Lorenzo; Prato, Stefano; Pittana, Paolo; Gatteschi, Dante

    2004-01-01

    Reading and manipulating the spin status of single magnetic molecules is of paramount importance both for applicative and fundamental purposes. The possibility to combine Electron Spin Resonance (ESR) and Scanning Tunnelling Microscopy (STM) has been explored one decade ago. A few experiments have raised the question whether or not an EPR spectrum of single molecule is detachable. Only a few data have been reported in modern surface science literature. To date it has yet to be proven till which extent ESR can be reliably and reproducibly performed on single molecules. We are setting up a new ESR-STM (spectrometer) to verify and study the effect of spin-spin correlations in the frequency spectrum of the tunneling current which flows through a single magnetic adsorbate and a metal surface. Here we discuss, the major experimental challenges that we are attempting to overcome.

  11. Free radicals and SOD activity of jaw cyst. Direct measurement and spin trapping studies by ESR.

    Science.gov (United States)

    Kimura, H; Simodate, H; Suzuki, M

    1990-01-01

    Free radicals produced in the fluid of jaw cysts were directly measured at room temperature using ESR. With these samples, SOD activity of the cyst fluid was measured by the ESR spin trapping method with DMPO as a trapping agent. Freeze-dried samples of cyst fluid showed a broad ESR signal at g = 2.005. Relative signal intensity of samples from jaw cysts with inflammation was higher than jaw cysts without inflammation. SOD activity of cyst fluid with high viscosity showed higher values than that of cyst fluid with low viscosity. We suggest that free radicals produced in jaw cyst damage tissues while higher SOD activity of cyst fluid play a role in a self-defense mechanism against free radicals.

  12. Acoustic dispersive prism

    OpenAIRE

    Hussein Esfahlani; Sami Karkar; Herve Lissek; Mosig, Juan R.

    2016-01-01

    The optical dispersive prism is a well-studied element, which allows separating white light into its constituent spectral colors, and stands in nature as water droplets. In analogy to this definition, the acoustic dispersive prism should be an acoustic device with capability of splitting a broadband acoustic wave into its constituent Fourier components. However, due to the acoustical nature of materials as well as the design and fabrication difficulties, there is neither any natural acoustic ...

  13. ESR investigation of structure and dynamics of paramagnetic centres in lime mortars from Budinjak, Croatia

    International Nuclear Information System (INIS)

    This study presents the preliminary results of investigation of the types and dynamics of paramagnetic centres in lime mortars from Sveta Petka church in Budinjak, Croatia, using Electron Spin Resonance (ESR) spectroscopy. The excavation in Budinjak discovered a very unique four lobed plan object Sveta Petka, with no additional finds or reliable historical records about the time of its construction. The lime mortars from the church were chosen for analysis in order to characterize the building material and to verify the site chronology by dating them. Lime mortar is valuable but problematic material for luminescence and radiocarbon dating. This type of material has not been dated before using ESR; therefore, careful studies are required to identify the useful paramagnetic centres. The ESR approach suggested in this work concentrates on a calcium carbonate signal. All samples were γ-irradiated in 60C bomb with the doses of 1, 10, 20, 50, 80 and 100 kGy. In all spectra signals from Fe3+ and Mn2+ ions have been observed. Paramagnetic centres which give the ESR signals may be interpreted as CO2−, CO3−, CO33−, HCO32−, SO2−, SO3−, PO2− and PO32− species. However, all spectra are complex and signals are interfering; therefore, computer resolution enhancement method will be needed in further research. The changes in ESR signals amplitude measured at magnetic field range about 3440–3450 G were analysed versus the dose of irradiation, using Mn2+ signals as a reference. Exponential growth of the curve and saturation for doses above 20 kGy were observed; therefore, irradiation with smaller doses is required. These preliminary studies will be helpful in future attempts of dating lime mortars by ESR method.

  14. Mechanism of Cr(VI) adsorption by coir pith studied by ESR and adsorption kinetic

    Energy Technology Data Exchange (ETDEWEB)

    Suksabye, Parinda [Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 91 Pracha-Utit Road, Bangmod, Thungkru, Bangkok 10140 (Thailand); Nakajima, Akira [Division of Chemistry, Department of Medical Science, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889 1692 (Japan); Thiravetyan, Paitip [Division of Biotechnology, School of Bioresources and Technology, King Mongkut' s University of Technology Thonburi, 83 Moo.8 Thakham, Bangkhuntien, Bangkok 10150 (Thailand)], E-mail: paitip.thi@kmutt.ac.th; Baba, Yoshinari [Department of applied Chemistry, Faculty of Technology, University of Miyazaki, Gakuen-Kibabadai, Miyazaki 889 2192 (Japan); Nakbanpote, Woranan [Pilot Plant Development and Training Institute, King Mongkut' s University of Technology Thonburi, 83 Moo.8 Thakham, Bangkhuntien, Bangkok 10150 (Thailand)

    2009-01-30

    The oxidation state of chromium in coir pith after Cr(VI) adsorption from aqueous solution was investigated using electron spin resonance (ESR). To elucidate the mechanism of chromium adsorption on coir pith, the adsorption studies of Cr(VI) onto lignin, {alpha}-cellulose and holocellulose extracted from coir pith were also studied. ESR signals of Cr(V) and Cr(III) were observed in coir pith adsorbed Cr(VI) at solution pH 2, while ESR spectra of lignin extracted from coir pith revealed only the Cr(III) signal. In addition, ESR signal of Cr(V) was observed in {alpha}-cellulose and holocellulose extracted from coir pith adsorbed Cr(VI). These results confirmed that lignin in coir pith reduced Cr(VI) to Cr(III) while {alpha}-cellulose and holocellulose extracted from coir pith reduced Cr(VI) to Cr(V). The Cr(V) signal exhibited in ESR of {alpha}-cellulose and holocellulose might be bound with glucose in cellulose part of coir pith. In addition, xylose which is main in pentosan part of coir pith, indicated that it is involved in form complex with Cr(V) on coir pith. The adsorption kinetic of Cr(VI) from aqueous solution on coir pith was also investigated and described well with pseudo second order model. ESR and desorption experiments confirmed that Cr(VI), Cr(V) and Cr(III), exist in coir pith after Cr(VI) adsorption. The desorption data indicated that the percentage of Cr(VI), Cr(V) and Cr(III) in coir pith were 15.63%, 12.89% and 71.48%, respectively.

  15. Molecular Characterization and Sex-Specific Tissue Expression of Estrogen Receptor Alpha (esr1), Estrogen Receptor Beta-a (esr2a) and Ovarian Aromatase (cyp19a1a) in Yellow Perch (Perca flavescens)

    Science.gov (United States)

    Yellow perch (Perca flavescens) exhibit an estrogen-stimulated sexual size dimorphism (SSD) wherein females grow faster and larger than males. To aid in the examination of this phenomenon, the cDNA sequences encoding estrogen receptor-alpha (esr1), estrogen receptor-beta-a (esr2a) and ovarian aroma...

  16. Dynamic nuclear polarization-magnetic resonance imaging at low ESR irradiation frequency for ascorbyl free radicals

    OpenAIRE

    Shinji Ito; Fuminori Hyodo

    2016-01-01

    Highly water-soluble ubiquinone-0 (CoQ0) reacts with ascorbate monoanion (Asc) to mediate the production of ascorbyl free radicals (AFR). Using aqueous reaction mixture of CoQ0 and Asc, we obtained positively enhanced dynamic nuclear polarization (DNP)-magnetic resonance (MR) images of the AFR at low frequency (ranging from 515 to 530 MHz) of electron spin resonance (ESR) irradiation. The shape of the determined DNP spectrum was similar to ESR absorption spectra with doublet spectral peaks. T...

  17. Discrete Generalized Observables and Ideal Measurements in the ESR Model: A Hilbert Space Representation

    Science.gov (United States)

    Sozzo, Sandro

    2009-03-01

    The extended semantic realism (ESR) model embodies the mathematical formalism of standard (Hilbert space) quantum mechanics (QM) in a noncontextual framework, reinterpreting quantum probabilities as conditional instead of absolute. We provide here a Hilbert space representation of the discrete generalized observables introduced by the ESR model that satisfy a simple physical condition, propose a generalization of the projection postulate and suggest a possible mathematical description of an ideal measurement process in terms of evolution of the compound system made up of the measured system and the measuring apparatus.

  18. A Hilbert Space Representation of Generalized Observables and Measurement Processes in the ESR Model

    Science.gov (United States)

    Sozzo, Sandro; Garola, Claudio

    2010-12-01

    The extended semantic realism ( ESR) model recently worked out by one of the authors embodies the mathematical formalism of standard (Hilbert space) quantum mechanics in a noncontextual framework, reinterpreting quantum probabilities as conditional instead of absolute. We provide here a Hilbert space representation of the generalized observables introduced by the ESR model that satisfy a simple physical condition, propose a generalization of the projection postulate, and suggest a possible mathematical description of the measurement process in terms of evolution of the compound system made up of the measured system and the measuring apparatus.

  19. The ESR model: A proposal for a noncontextual and local Hilbert space extension of QM

    Science.gov (United States)

    Garola, C.; Sozzo, S.

    2009-04-01

    The extended semantic realism (ESR) model proposes a new theoretical perspective that embodies the mathematical formalism of standard (Hilbert space) quantum mechanics (QM) in a noncontextual framework, reinterpreting quantum probabilities as conditional instead of absolute. We provide here a Hilbert space representation of the generalized observables introduced by the ESR model. By using this representation, we supply a straightforward generalization of the projection postulate and justify it in the case of discrete generalized observables by introducing a reasonable physical assumption on the evolution of the compound system made up of the (microscopic) measured system and the (macroscopic) measuring apparatus.

  20. ESR analysis of point defects produced in quartz by fast and thermal neutron irradiation

    International Nuclear Information System (INIS)

    ESR signals derived from intrinsic lattice defects in quartz, oxygen vacancies and interstitials, were detected by gamma or neutron irradiation. In addition, an unknown ESR signal at g=2.0050 also was detected by neutron irradiation. This unknown signal may be a superoxide (O2-) produced in depleted zones in quartz, which are formed by knock-on with fast neutrons. Microwave power characteristics indicates that this unknown signal is quite different from a peroxy center (Si-O-O·) although both signals can be produced by knock-on. (author)

  1. Investigation of hydrogen atom addition to vinyl monomers by time resolved ESR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Beckert, D.; Mehler, K.

    1983-07-01

    By means of time resolved ESR spectroscopy in the microsecond time scale the H atom addition to different vinyl monomers was investigated. The H atoms produced by pulse radiolysis of aqueous solutions show a strong recombination CIDEP effect which also allows the recombination rate constant of H atoms to be determined. By analysis of ESR time profiles with the modified Bloch equations the relaxation times T/sub 1/, T/sub 2/, the polarization factors and the chemical rate constants with scavengers were obtained. Besides the H atom addition rate constants to different vinyl monomers the structure of the monomer radical was determined for acrylic acid.

  2. ESR studies of the magnetism in Ru-1212 and Ru-2212

    International Nuclear Information System (INIS)

    We have studied by electron spin resonance (ESR) the nonsuperconducting system Ru-1212 and the superconducting and nonsuperconducting Ru-2212 over the temperature range 100-300 K, in the normal and magnetic phases. In the nonsuperconducting Ru-1212 we found that the ferromagnetic line appears at a much higher temperature than the magnetic ordering as determined by neutron diffraction. We also show a correlation between the temperature dependence of the intensity and width of the ESR resonance lines, the intensity of magnetic absorption lines and the DC magnetization measurements. (orig.)

  3. Development of a multi-frequency ESR system with high sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Yashiro, H [KYOKUGEN, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan); Kashiwagi, T [KYOKUGEN, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan); Horitani, M [Division of Bioengineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Hobo, F [International Graduate School of Arts and Sciences, Yokohama City University, Suehiro 1-7-29, Tsurumi, Yokohama, Kanagawa, 230-0045 (Japan); Hori, H [Division of Bioengineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Hagiwara, M [KYOKUGEN, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan)

    2006-11-15

    We have developed a new Multi-Frequency (MF) ESR system for the frequencies between 35 to 130 GHz utilizing TE{sub 011} single mode resonators. Their sensitivities (10{sup 10}spins/G at 1.5 K) are comparable to that of a conventional low frequency ESR resonator and an order of magnitude higher than that of a Fabry Perot resonator which was previously developed by us. Thanks to a newly developed precise and stable matching system, we observed for the first time MFESR spectra of a metalloprotein with an integer spin.

  4. Development of a multi-frequency ESR system with high sensitivity

    Science.gov (United States)

    Yashiro, H.; Kashiwagi, T.; Horitani, M.; Hobo, F.; Hori, H.; Hagiwara, M.

    2006-11-01

    We have developed a new Multi-Frequency (MF) ESR system for the frequencies between 35 to 130 GHz utilizing TE011 single mode resonators. Their sensitivities (1010spins/G at 1.5 K) are comparable to that of a conventional low frequency ESR resonator and an order of magnitude higher than that of a Fabry Perot resonator which was previously developed by us. Thanks to a newly developed precise and stable matching system, we observed for the first time MFESR spectra of a metalloprotein with an integer spin.

  5. Effects of alpha radiation on plutonium incorporated in dosimetric materials by ESR studies

    International Nuclear Information System (INIS)

    The in situ alpha irradiation effects of some ESR dosimetric materials namely alanine, 2-methyl alanine and ammonium tartrate were studied by incorporating 1% plutonium by weight in them. The radical intensity was monitored as a function of alpha dose. It was found that in the dose region 1-35 kGy ammonium tartrate showed better signal intensity, linearity and dose response as compared to the other materials. This was attributed to the single radical produced in case of the tartrate giving a sharp spectrum and the fast relaxation times owing to less saturation of ESR signals. (author)

  6. Regeneration of phenolic antioxidants from phenoxyl radicals: An ESR and electrochemical study of antioxidant hierarchy

    DEFF Research Database (Denmark)

    Jørgensen, Lars V.; Madsen, Helle L.; Thomsen, Marianne K.;

    1999-01-01

    Radicals from the flavonoids quercetin, (+)-catechin, (+/-)-taxifolin and luteolin, and from all-rac-alpha-tocopherol have been generated electrochemically by one-electron oxidation in deaerated dimethylformamide (DMF), and characterised by electron spin resonance spectroscopy (ESR) after spin......-trapping by 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). Simulations of the ESR spectrum based on estimated coupling constants of the spin-trapped quercetin radical, confirmed that this antioxidant radical is oxygen-centered. The complex mixture of radicals, quinoid intermediates and stable two-electron oxidation...

  7. Determination of isodose curves in Radiotherapy using an Alanine/ESR dosemeter; Determinacion de curvas de isodosis en Radioterapia usando un dosimetro de Alanina/ESR

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F.; Baffa, O.; Graeff, C.F.O. [Departamento de Fisica e Matematica. Universidade de Sao Paulo FFCLRP. 14040-901 Ribeirao Preto-SP (Brazil)

    1998-12-31

    It was studied the possible use of an Alanine/ESR dosemeter in the isodose curves mapping in normal treatments of Radiotherapy. It was manufactured a lot of 150 dosemeters with base in a mixture of D-L Alanine dust (80 %) and paraffin (20 %). Each dosemeter has 4.7 mm diameter and 12 mm length. A group of 100 dosemeters of the lot were arranged inside 50 holes of the slice 25 of the phantom Rando Man. The phantom irradiation was realized in two opposed projections (AP and PA) in Co-60 equipment. A group of 15 dosemeters was take of the same lot for obtaining the calibration curve in a 1-20 Gy range. After irradiation the signal of each dosemeter was measured in an ESR spectrometer operating in the X-band ({approx} 9.5 GHz) and the wideness of Alanine ESR spectra central line was correlated with the radiation dose. The wideness dose calibration curve resulted linear with a correlation coefficient 0.9996. The isodose curves obtained show a profile enough similar at comparing with the theoretical curves. (Author)

  8. Responsive acoustic surfaces

    DEFF Research Database (Denmark)

    Peters, Brady; Tamke, Martin; Nielsen, Stig Anton;

    2011-01-01

    Acoustic performance is defined by the parameter of reverberation time; however, this does not capture the acoustic experience in some types of open plan spaces. As many working and learning activities now take place in open plan spaces, it is important to be able to understand and design...... for the acoustic conditions of these spaces. This paper describes an experimental research project that studied the design processes necessary to design for sound. A responsive acoustic surface was designed, fabricated and tested. This acoustic surface was designed to create specific sonic effects. The design...... was simulated using custom integrated acoustic software and also using Odeon acoustic analysis software. The research demonstrates a method for designing space- and sound-defining surfaces, defines the concept of acoustic subspace, and suggests some new parameters for defining acoustic subspaces....

  9. Springer Handbook of Acoustics

    CERN Document Server

    Rossing, Thomas D

    2007-01-01

    Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and others. The Springer Handbook of Acoustics is an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents spanning: animal acoustics including infrasound and ultrasound, environmental noise control, music and human speech and singing, physiological and psychological acoustics, architectural acoustics, physical and engineering acoustics, signal processing, medical acoustics, and ocean acoustics. This handbook reviews the most important areas of acoustics, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest rese...

  10. Acoustic Spatiality

    Directory of Open Access Journals (Sweden)

    Brandon LaBelle

    2012-06-01

    Full Text Available Experiences of listening can be appreciated as intensely relational, bringing us into contact with surrounding events, bodies and things. Given that sound propagates and expands outwardly, as a set of oscillations from a particular source, listening carries with it a sensual intensity, whereby auditory phenomena deliver intrusive and disruptive as well as soothing and assuring experiences. The physicality characteristic of sound suggests a deeply impressionistic, locational "knowledge structure" – that is, the ways in which listening affords processes of exchange, of being in the world, and from which we extend ourselves. Sound, as physical energy reflecting and absorbing into the materiality around us, and even one's self, provides a rich platform for understanding place and emplacement. Sound is always already a trace of location.Such features of auditory experience give suggestion for what I may call an acoustical paradigm – how sound sets in motion not only the material world but also the flows of the imagination, lending to forces of signification and social structure, and figuring us in relation to each other. The relationality of sound brings us into a steady web of interferences, each of which announces the promise or problematic of being somewhere.

  11. Acoustic Neurinomas

    Directory of Open Access Journals (Sweden)

    Mohammad Faraji Rad

    2011-01-01

    Full Text Available Acoustic neuromas (AN are schwann cell-derived tumors that commonly arise from the vestibular portion of the eighth cranial nerve also known as vestibular schwannoma(VS causes unilateral hearing loss, tinnitus, vertigo and unsteadiness. In many cases, the tumor size may remain unchanged for many years following diagnosis, which is typically made by MRI. In the majority of cases the tumor is small, leaving the clinician and patient with the options of either serial scanning or active treatment by gamma knife radiosurgery (GKR or microneurosurgery. Despite the vast number of published treatment reports, comparative studies are few. The predominant clinical endpoints of AN treatment include tumor control, facial nerve function and hearing preservation. Less focus has been put on symptom relief and health-related quality of life (QOL. It is uncertain if treating a small tumor leaves the patient with a better chance of obtaining relief from future hearing loss, vertigo or tinnitus than by observing it without treatment.   In this paper we review the literature for the natural course, the treatment alternatives and the results of AN. Finally, we present our experience with a management strategy applied for more than 30 years.

  12. Ion-acoustic solitary waves and spectrally uniform scattering cross section enhancements

    Directory of Open Access Journals (Sweden)

    J. Ekeberg

    2010-06-01

    Full Text Available Spectra measured by incoherent scatter radars are formed predominantly by scattering of the incident signal off ion-acoustic and Langmuir waves in the ionosphere. Occasionally, the upshifted and/or downshifted lines produced by the ion-acoustic waves are enhanced well above thermal levels and referred to as naturally enhanced ion-acoustic lines. In this paper, we study another kind of enhancement, which is spectrally uniform over the whole ion-line, i.e. the up- and downshifted shoulder and the spectral valley in between. Based on observations made with the EISCAT Svalbard radar (ESR facility, we investigate the transient and spectrally uniform power enhancements, which can be explained by ion-acoustic solitary waves. We use a theory of nonlinear waves in a magnetized plasma to determine the properties of such waves and evaluate their effects on scattered signals measured by ESR. We suggest a new mechanism that can explain backscattered power enhancements by one order of magnitude above the thermal level and show that it is consistent with observations.

  13. Amplification of ESR1 may predict resistance to adjuvant tamoxifen in postmenopausal patients with hormone receptor positive breast cancer

    DEFF Research Database (Denmark)

    Nielsen, Kirsten Vang; Ejlertsen, Bent; Müller, Sven;

    2011-01-01

    The estrogen receptor (ER) is the target of tamoxifen, but endocrine therapies do not benefit all patients with ER positive tumors. We therefore hypothesized that copy number changes in the ESR1 gene, encoding ER, confer resistance. Within a consecutive series of ER positive, postmenopausal...... was significantly associated with poor disease-free survival (P = 0.0054) and overall survival (P = 0.0004). This pilot study supports our hypothesis that ESR1 amplification is associated with a poorer outcome following adjuvant treatment with tamoxifen in ER positive early breast cancer. This study also revealed......1 copy number changes using FISH with a probe covering the ESR1 gene at 6q25 and a reference probe covering the centromere of chromosome 6. The assay was validated in a material of 120 normal breast samples. FISH analysis for ESR1 was successful in 91 patients (94%). Amplification (ratio ESR1/CEN-6...

  14. Acoustic source for generating an acoustic beam

    Energy Technology Data Exchange (ETDEWEB)

    Vu, Cung Khac; Sinha, Dipen N.; Pantea, Cristian

    2016-05-31

    An acoustic source for generating an acoustic beam includes a housing; a plurality of spaced apart piezo-electric layers disposed within the housing; and a non-linear medium filling between the plurality of layers. Each of the plurality of piezoelectric layers is configured to generate an acoustic wave. The non-linear medium and the plurality of piezo-electric material layers have a matching impedance so as to enhance a transmission of the acoustic wave generated by each of plurality of layers through the remaining plurality of layers.

  15. Validity and predictive ability of the juvenile arthritis disease activity score based on CRP versus ESR in a Nordic population-based setting

    DEFF Research Database (Denmark)

    Nordal, E B; Zak, Marek Stanislaw; Aalto, K;

    2012-01-01

    To compare the juvenile arthritis disease activity score (JADAS) based on C reactive protein (CRP) (JADAS-CRP) with JADAS based on erythrocyte sedimentation rate (ESR) (JADAS-ESR) and to validate JADAS in a population-based setting.......To compare the juvenile arthritis disease activity score (JADAS) based on C reactive protein (CRP) (JADAS-CRP) with JADAS based on erythrocyte sedimentation rate (ESR) (JADAS-ESR) and to validate JADAS in a population-based setting....

  16. Canonical Acoustics and Its Application to Surface Acoustic Wave on Acoustic Metamaterials

    Science.gov (United States)

    Shen, Jian Qi

    2016-08-01

    In a conventional formalism of acoustics, acoustic pressure p and velocity field u are used for characterizing acoustic waves propagating inside elastic/acoustic materials. We shall treat some fundamental problems relevant to acoustic wave propagation alternatively by using canonical acoustics (a more concise and compact formalism of acoustic dynamics), in which an acoustic scalar potential and an acoustic vector potential (Φ ,V), instead of the conventional acoustic field quantities such as acoustic pressure and velocity field (p,u) for characterizing acoustic waves, have been defined as the fundamental variables. The canonical formalism of the acoustic energy-momentum tensor is derived in terms of the acoustic potentials. Both the acoustic Hamiltonian density and the acoustic Lagrangian density have been defined, and based on this formulation, the acoustic wave quantization in a fluid is also developed. Such a formalism of acoustic potentials is employed to the problem of negative-mass-density assisted surface acoustic wave that is a highly localized surface bound state (an eigenstate of the acoustic wave equations). Since such a surface acoustic wave can be strongly confined to an interface between an acoustic metamaterial (e.g., fluid-solid composite structures with a negative dynamical mass density) and an ordinary material (with a positive mass density), it will give rise to an effect of acoustic field enhancement on the acoustic interface, and would have potential applications in acoustic device design for acoustic wave control.

  17. Association of ESR1 gene tagging SNPs with breast cancer risk

    DEFF Research Database (Denmark)

    Dunning, Alison M; Healey, Catherine S; Baynes, Caroline;

    2009-01-01

    We have conducted a three-stage, comprehensive single nucleotide polymorphism (SNP)-tagging association study of ESR1 gene variants (SNPs) in more than 55,000 breast cancer cases and controls from studies within the Breast Cancer Association Consortium (BCAC). No large risks or highly significant...

  18. ESR and AMS-based C-14 dating of Mousterian levels at Mujina Pecina, Dalmatia, Croatia

    NARCIS (Netherlands)

    Rink, WJ; Karavanic, [No Value; Pettitt, PB; Van der Plicht, J; Smith, FH; Bartoll, J

    2002-01-01

    This paper presents the first chronometric dates for sediments that contain a Mousterian industry in Dalmatia (south Croatia). Electron spin resonance (ESR) dating was conducted on two teeth from the Mousterian level E1 at the site of Mujina Pecina. Additionally five bone and one charcoal sample fro

  19. Dynamic nuclear polarization-magnetic resonance imaging at low ESR irradiation frequency for ascorbyl free radicals

    Science.gov (United States)

    Ito, Shinji; Hyodo, Fuminori

    2016-02-01

    Highly water-soluble ubiquinone-0 (CoQ0) reacts with ascorbate monoanion (Asc) to mediate the production of ascorbyl free radicals (AFR). Using aqueous reaction mixture of CoQ0 and Asc, we obtained positively enhanced dynamic nuclear polarization (DNP)-magnetic resonance (MR) images of the AFR at low frequency (ranging from 515 to 530 MHz) of electron spin resonance (ESR) irradiation. The shape of the determined DNP spectrum was similar to ESR absorption spectra with doublet spectral peaks. The relative locational relationship of spectral peaks in the DNP spectra between the AFR (520 and 525 MHz), 14N-labeled carbamoyl-PROXYL (14N-CmP) (526.5 MHz), and Oxo63 (522 MHz) was different from that in the X-band ESR spectra, but were similar to that in the 300-MHz ESR spectra. The ratio of DNP enhancement to radical concentration for the AFR was higher than those for 14N-CmP, Oxo63, and flavin semiquinone radicals. The spectroscopic DNP properties observed for the AFR were essentially the same as those for AFR mediated by pyrroloquinoline quinone. Moreover, we made a success of in vivo DNP-MR imaging of the CoQ0-mediated AFR which was administered by the subcutaneous and oral injections as an imaging probe.

  20. Generalized Observables, Bell's Inequalities and Mixtures in the ESR Model for QM

    Science.gov (United States)

    Garola, Claudio; Sozzo, Sandro

    2011-03-01

    The extended semantic realism ( ESR) model proposes a new theoretical perspective which embodies the mathematical formalism of standard (Hilbert space) quantum mechanics (QM) into a noncontextual framework, reinterpreting quantum probabilities as conditional instead of absolute. We provide in this review an overall view on the present status of our research on this topic. We attain in a new, shortened way a mathematical representation of the generalized observables introduced by the ESR model and a generalization of the projection postulate of elementary QM. Basing on these results we prove that the Bell-Clauser-Horne-Shimony-Holt (BCHSH) inequality, a modified BCHSH inequality and quantum predictions hold together in the ESR model because they refer to different parts of the picture of the physical world supplied by the model. Then we show that a new mathematical representation of mixtures must be introduced in the ESR model which does not coincide with the standard representation in QM and avoids some deep problems that arise from the representation of mixtures provided by QM. Finally we get a nontrivial generalization of the Lüders postulate, which is justified in a special case by introducing a reasonable physical assumption on the evolution of the compound system made up of the measured system and the measuring apparatus.

  1. The use of ESR technique for assessment of heating temperatures of archaeological lentil samples

    Science.gov (United States)

    Aydaş, Canan; Engin, Birol; Dönmez, Emel Oybak; Belli, Oktay

    2010-01-01

    Heat-induced paramagnetic centers in modern and archaeological lentils ( Lens culinaris, Medik.) were studied by X-band (9.3 GHz) electron spin resonance (ESR) technique. The modern red lentil samples were heated in an electrical furnace at increasing temperatures in the range 70-500 °C. The ESR spectral parameters (the intensity, g-value and peak-to-peak line width) of the heat-induced organic radicals were investigated for modern red lentil ( Lens culinaris, Medik.) samples. The obtained ESR spectra indicate that the relative number of heat-induced paramagnetic species and peak-to-peak line widths depends on the temperature and heating time of the modern lentil. The g-values also depend on the heating temperature but not heating time. Heated modern red lentils produced a range of organic radicals with g-values from g = 2.0062 to 2.0035. ESR signals of carbonised archaeological lentil samples from two archaeological deposits of the Van province in Turkey were studied and g-values, peak-to-peak line widths, intensities and elemental compositions were compared with those obtained for modern samples in order to assess at which temperature these archaeological lentils were heated in prehistoric sites. The maximum temperatures of the previous heating of carbonised UA5 and Y11 lentil seeds are as follows about 500 °C and above 500 °C, respectively.

  2. NMR and ESR characterization of activated carbons produced from pecan shells

    Science.gov (United States)

    A large number of solid-state NMR and ESR experiments were explored as potential tools to study chemical structure, mobility, and pore volume of activated carbon. We used a model system where pecan shells were activated with phosphoric acid, and carbonized at 450ºC for 4 h with varying amounts of ai...

  3. Haplotype analysis of ESR2 in Japanese patients with spermatogenic failure.

    Science.gov (United States)

    Ogata, Tsutomu; Fukami, Maki; Yoshida, Rie; Nagata, Eiko; Fujisawa, Yasuko; Yoshida, Atsumi; Yoshimura, Yasunori

    2012-07-01

    The prevalence of spermatogenic failure (SF) has gradually increased during the past few decades at least in several countries. Although multiple factors would be involved in this phenomenon, one important factor would be excessive estrogen effects via estrogen receptors (ERs). Thus, we performed haplotype analysis of ESR2 encoding ERβ in 125 Japanese SF patients and 119 age-matched control males, using single nucleotide polymorphisms (SNPs) 1-9 that are widely distributed on the ~120-kb genomic sequence of ESR2. Consequently, a linkage disequilibrium (LD) block was detected in an ~60-kb region encompassing SNPs 2-7 in both groups, and four major estimated haplotypes were identified within the LD block. Furthermore, the most prevalent 'TGTAGA' haplotype was found to be significantly associated with SF, with the P-value obtained by the Cochran-Armitage trend test (0.0029) being lower than that obtained by a 100 000-times permutation test (0.0038) to cope with the problem of multiple comparisons. The results, in conjunction with our previous data indicating lack of a susceptibility factor on ESR1 encoding ERα, imply that the specific 'TGTAGA' haplotype of ESR2 raises the susceptibility to the development of SF.

  4. Alanine ESR dosimetry as a travelling dosimetric system for intercomparison purposes

    Energy Technology Data Exchange (ETDEWEB)

    Bartolotta, A. (Palermo Univ. (Italy). Ist. di Fisica); Onori, S.; Pantaloni, M. (Istituto Superiore di Sanita, Rome (Italy). Lab. di Fisica)

    1990-01-01

    The major features of the ESR alanine dosimetry set up at the ISS are discussed, with particular regards to those aspects which render it suitable as travelling dosimetric system, both for photon and electron beams. The main results of an intercomparison program among the routine dosimetric systems used at the Italian industrial irradiation plants are shown.

  5. ESR dating of calcrete nodules from Bala, Ankara (Turkey): preliminary results.

    Science.gov (United States)

    Küçükuysal, Ceren; Engin, Birol; Türkmenoğlu, Asuman G; Aydaş, Canan

    2011-02-01

    The age of two calcrete nodules (C1 and C2) from the Bala section in the region of Ankara, Turkey, is determined by the Electron Spin Resonance (ESR) method. Three radiation-induced ESR signals at g=2.0056 (A signal), g=2.0006 (C signal) and g=2.0038 (broad signal, BL) were observed. The broad signal (BL) intensity was used as a dating signal. The properties of this dating signal are described in this manuscript. The calcrete nodules were irradiated with a (60)Co gamma source and measured with an ESR spectrometer (X-band) to obtain the signal intensity vs. dose curve and fitted well with the single exponential saturation functions. Based on this model, accumulated dose (D(E)) values for dating are obtained using the multiple-aliquot additive dose method. The D(E) values of C1 and C2 calcretes are 1880±207 and 671±67 Gy, respectively. The ESR ages of the two calcrete samples are obtained by assessing the annual dose rate (D) from the content of (238)U, (232)Th and K(2)O determined by wavelength dispersive X-ray fluorescence (XRF) spectrometry. The results are 761±120 and 419±64 ka, respectively, falling into the Middle Pleistocene Epoch in the geological time scale in agreement with the positions of the stratigraphical record.

  6. ESR dating of calcrete nodules from Bala, Ankara (Turkey): Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Kuecuekuysal, Ceren [General Directorate of Mineral Research and Exploration, Geological Research Department, 06800 Ankara (Turkey); Engin, Birol, E-mail: birol_engin65@yahoo.co [Turkish Atomic Energy Authority, Saraykoey Nuclear Research and Training Center, 06983 Ankara (Turkey); Tuerkmenoglu, Asuman G. [Middle East Technical University, Geological Engineering Department, 06531 Ankara (Turkey); Aydas, Canan [Turkish Atomic Energy Authority, Saraykoey Nuclear Research and Training Center, 06983 Ankara (Turkey)

    2011-02-15

    The age of two calcrete nodules (C1 and C2) from the Bala section in the region of Ankara, Turkey, is determined by the Electron Spin Resonance (ESR) method. Three radiation-induced ESR signals at g=2.0056 (A signal), g=2.0006 (C signal) and g=2.0038 (broad signal, BL) were observed. The broad signal (BL) intensity was used as a dating signal. The properties of this dating signal are described in this manuscript. The calcrete nodules were irradiated with a {sup 60}Co gamma source and measured with an ESR spectrometer (X-band) to obtain the signal intensity vs. dose curve and fitted well with the single exponential saturation functions. Based on this model, accumulated dose (D{sub E}) values for dating are obtained using the multiple-aliquot additive dose method. The D{sub E} values of C1 and C2 calcretes are 1880{+-}207 and 671{+-}67 Gy, respectively. The ESR ages of the two calcrete samples are obtained by assessing the annual dose rate (D) from the content of {sup 238}U, {sup 232}Th and K{sub 2}O determined by wavelength dispersive X-ray fluorescence (XRF) spectrometry. The results are 761{+-}120 and 419{+-}64 ka, respectively, falling into the Middle Pleistocene Epoch in the geological time scale in agreement with the positions of the stratigraphical record.

  7. Dynamic rayed aurora and enhanced ion-acoustic radar echoes

    Directory of Open Access Journals (Sweden)

    E. M. Blixt

    2005-01-01

    Full Text Available The generation mechanism for naturally enhanced ion-acoustic echoes is still debated. One important issue is how these enhancements are related to auroral activity. All events of enhanced ion-acoustic echoes observed simultaneously with the EISCAT Svalbard Radar (ESR and with high-resolution narrow field-of-view auroral imagers have been collected and studied. Characteristic of all the events is the appearance of very dynamic rayed aurora, and some of the intrinsic features of these auroral displays are identified. Several of these identified features are directly related to the presence of low energy (10-100eV precipitating electrons in addition to the higher energy population producing most of the associated light. The low energy contribution is vital for the formation of the enhanced ion-acoustic echoes. We argue that this type of aurora is sufficient for the generation of naturally enhanced ion-acoustic echoes. In one event two imagers were used to observe the auroral rays simultaneously, one from the radar site and one 7km away. The data from these imagers shows that the auroral rays and the strong backscattering filaments (where the enhanced echoes are produced are located on the same field line, which is in contrast to earlier statements in the litterature that they should be separated.

  8. Expression of estrogen receptor α 36 (ESR36 in the hamster ovary throughout the estrous cycle: effects of gonadotropins.

    Directory of Open Access Journals (Sweden)

    Prabuddha Chakraborty

    Full Text Available Estradiol-17β (E plays an important role in ovarian follicular development. Evidence indicates that some of the effect of E is mediated by the transmembrane estrogen receptor. In this study, we examined the spatio-temporal expression of recently discovered ERα36 (ESR36, a splice variant of Esr1 and a receptor for non-genomic E signaling, in the hamster ovary during the estrous cycle and the role of gonadotropins and ovarian steroid hormones in ESR36 expression. ESR36 expression was high on estrus (D1:0900 h and declined precipitously by proestrus (D4:0900 h and remained low up to D4:1600 h. Immunofluorescence findings corroborated immunoblot findings and revealed that ESR36 was expressed only in the cell membrane of both follicular and non-follicular cells, except the oocytes. Ovarian ESR36 was capable of binding to the E-affinity matrix, and have different molecular weight than that of the ESR1 or GPER. Hypophysectomy (Hx resulted in a marked decline in ESR36 protein levels. FSH and LH, alone or combined, markedly upregulated ESR36 protein in Hx hamsters to the levels observed in D1 hamsters, but neither E nor P had any effect. Inhibition of the gonadotropin surge by phenobarbital treatment on D4:1100 h attenuated ESR36 expression in D1:0900 h ovaries, but the decline was restored by either FSH or LH replacement on D4 afternoon. This is the first report to show that ESR36, which is distinct from ESR1 or GPER is expressed in the plasma membrane of ovarian follicular and non-follicular cells, binds to E and its expression is regulated directly by the gonadotropins. In light of our previous findings, the results suggest that ovarian cells contain at least two distinct membrane estrogen receptors, such as GPER and ESR36, and strongly suggest for a non-genomic action of E regulating ovarian follicular functions.

  9. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Join/Renew Ways to Give ANA Discussion Forum ... ANA Annual Reports Acoustic Neuroma Legacy Society Programs & Services Search ANAUSA.org Connect with us! Educational Video ...

  10. Atlantic Herring Acoustic Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Advanced Sampling Technologies Research Group conducts annual fisheries acoustic surveys using state-of-the-art acoustic, midwater trawling, and...

  11. Cystic acoustic neuromas

    OpenAIRE

    Chitkara, Naveen; Chanda, Rakesh; Yadav, S. P. S.; N.K. Sharma

    2002-01-01

    Predominantly cystic acoustic neuromas are rare and they usually present with clinical and radiological features different from their more common solid counterparts. Two cases of cystic acoustic neuromas are reported here.

  12. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... is ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic ... is ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic ...

  13. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ... Watch and Wait Radiation Microsurgery Acoustic Neuroma Decision Tree Questions for Your Physician Questions to Ask Yourself ...

  14. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... Resources Patient Surveys Related Links Clinical Trials.gov Health Care Insurance Toolkit Additional Resources ANA Public Webinars © 2016 Acoustic Neuroma Association Acoustic Neuroma Association ® • ...

  15. ESR and U-series analyses of enamel and dentine fragments of the Banyoles mandible.

    Science.gov (United States)

    Grün, Rainer; Maroto, Julià; Eggins, Stephen; Stringer, Chris; Robertson, Steve; Taylor, Lois; Mortimer, Graham; McCulloch, Malcolm

    2006-03-01

    The Banyoles mandible presents a puzzle. Its anatomy has been described as pre-Neandertal, but the travertine in which it was found has been dated to 45,000 +/- 4000 years. By this time, any pre-Neandertals had supposedly been absent from the European fossil record for more than 100,000 years. It was therefore proposed that the age of the travertine may represent a minimum age estimate, with the mandible possibly having been reworked from older deposits. We carried out a non-destructive ESR analysis of an enamel fragment removed from a molar and performed a series of in situ laser ablation U-series analyses on dentine fragments adjacent to the enamel piece. The analyses resulted in an apparent combined ESR-U-series age of 66,000 +/- 7000 years. The encasing travertine matrix was also analyzed for U-series isotopes and showed signs of U-mobilization. It cannot be excluded that the travertine matrix is older than the previously determined age. If the mandible was not reworked, then the combined ESR-U-series result on the tooth enamel would give its best age estimate. If, on the other hand, the mandible was reworked from another deposit, the actual ESR-U-series age will depend on the external dose rate from the previous matrix and the depth of its burial, which controls the degree of the attenuation of the cosmic dose rate over time. Considering a range of possible burial histories, the mean age of the mandible would lie somewhere between the combined ESR-U-series age and the previously determined age of the travertine matrix. Regarding the morphology of the mandible, a review of its features in the context of larger Neandertal samples indicates that the anatomy of the specimen is not incompatible with such a young age determination, although it further highlights morphological variation in the late Neandertal sample. PMID:16364406

  16. Hemolysin EthA in Edwardsiella tarda is essential for fish invasion in vivo and in vitro and regulated by two-component system EsrA-EsrB and nucleoid protein HhaEt.

    Science.gov (United States)

    Wang, Xin; Wang, Qiyao; Xiao, Jingfan; Liu, Qin; Wu, Haizhen; Zhang, Yuanxing

    2010-12-01

    Edwardsiella tarda is a Gram-negative pathogen for hemorrhagic septicemia in fish. Recently, two-component system (TCS) EsrA-EsrB in E. tarda has been found to play key roles in regulating type III secretion system (TTSS) and type VI secretion system (T6SS). In this study, a markedly attenuated ΔesrB mutant was investigated to exhibit enhanced cell-invasion capability, as well as the increased cytotoxicity of its extracellular products (ECPs). Compared with the parental strain, the ΔesrB mutant unexpectedly displayed the significantly increased hemolytic activity, and the restoration of hemolysin production was observed in the complemented strain esrB(+). A hemolysis-associated 147 kDa protein, EthA, was found to be up-regulated in the ECPs of ΔesrB. The deletion of ethA gene in E. tarda wild type and ΔesrB strains drastically decreased their capacities in internalization of epithelial papilloma of carp (EPC) cells. These results indicated that the increased production of EthA was responsible for the enhanced cell-invasion related capabilities in ΔesrB. Furthermore, the expression of EthA in ΔesrB exhibited a temperature-induced manner, and a nucleoid protein Hha(Et) was identified to mediate ethA expression by directly binding to its promoter. These results demonstrated that the virulence determinant EthA was fully required for invasion abilities of E. tarda and was subjected to the control of a complicated and precisely regulated network primed for its invasion, colonization and infection process in fish. PMID:20832475

  17. Tutorial on architectural acoustics

    Science.gov (United States)

    Shaw, Neil; Talaske, Rick; Bistafa, Sylvio

    2002-11-01

    This tutorial is intended to provide an overview of current knowledge and practice in architectural acoustics. Topics covered will include basic concepts and history, acoustics of small rooms (small rooms for speech such as classrooms and meeting rooms, music studios, small critical listening spaces such as home theatres) and the acoustics of large rooms (larger assembly halls, auditoria, and performance halls).

  18. Contribution of polymorphisms in ESR1, ESR2, FSHR, CYP19A1, SHBG and NRIP1 genes to migraine susceptibility in Turkish population

    Indian Academy of Sciences (India)

    Salih Coşkun; Yavuz Yücel; Abdullah Çim; Beyhan Cengiz; Serdar Oztuzcu; Sefer Varol; Hasan H. Özdemir; Ertuğrul Uzar

    2016-03-01

    Migraine, a highly prevalent headache disorder, is regarded as a polygenic multifactorial disease. Single-nucleotide polymorphisms (SNPs) in the genes that involved in sex hormone metabolism may comprise risk for migraine, but the results of previous genetic association studies are conflicting. The aim of this study was to evaluate genetic variants in genes involved in oestrogen receptor and oestrogen hormone metabolism in a Turkish population. A total of 12 SNPs in the ESR1, ESR2, FSHR, CYP19A1, SHBG and NRIP1 genes were genotyped in 142 migraine cases and 141 nonmigraine controls, using a BioMark 96.96 dynamic array system. In addition, gene–gene interactions were analysed using generalized multifactor dimensionality reduction (GMDR) methods. According to GMDR analysis, our results indicated that there was a significant association between migraine and gene–gene interaction among the CYP19A1, FSHR, ESR1 and NRIP1. Single-gene variant analysis showed that a significant association was observed between the TT genotype of rs10046 and migraine susceptibility.When the analysis was performed only in women, the GG genotype of rs2229741 was different between migraineurs and controls. When the female migraine patients were divided into two groups, migraine related to menstruation (MRM) or migraine not related to menstruation (MNRM), GG genotype of rs726281 was significantly associated with MRM. These results suggested that rs10046 could play a potential role in migraine susceptibility in Turkish population. Also, the rare GG genotype of rs726281 appears to influence migraine susceptibility in a recessive manner in MRM subgroup of female patients. In addition, variant GG genotype of rs2229741 may reduce the risk of migraine in Turkish women.

  19. Suitability of thermoluminescence, chemiluminescence, ESR and viscosity measurements as detection method for the irradiation of medicinal herbs; Eignung von Thermolumineszenz-, Chemilumineszenz-, ESR- und Viskositaetsmessungen zur Identifizierung strahlenbehandelter Arzneidrogen

    Energy Technology Data Exchange (ETDEWEB)

    Schuettler, C.; Gebhardt, G.; Stock, A.; Helle, N.; Boegl, K.W.

    1993-12-31

    Chemiluminescence, electron spin resonance, thermoluminescence and viscosity measurements have been investigated for their suitability as detection method for the irradiation of the medicinal herbs anise seeds (anisi fructus), valerian roots (valerianae radix), redberry leaves (uvae ursi folium), birch leaves (betulae folium), greek hay seeds (foenugraeci semen), cayenne pepper (capsici fructus acer), black-aldertee bark (frangulae cortex), fennel fruits (feoniculi fructus), rose hip shells (cynosbati fructus), coltsfoot (farfarae folium), acorus roots (calami rhizoma), chamomile flowers (matricariae flos), caraway (carvi fructus), lavender flowers (lavandulae flos), linseed (lini semen), lime tree flowers (tiliae flos), St. Mary`s thistle fruit (cardui mariae herba), lemon balm (melissae folium), java tea (orthosiphonis folium), peppermint (menthae piperitae folium), sage leaves (salviae folium), scouring rush (equiseti herba), senna leaves (sennae folium), plantain herbs (plantaginis lanceolata herba), thyme herbs (thymi herba), juniper berries (juniperi fructus), hawthorne herbs (crataegi folium), wheat starch (amylum tritici) and wormwood (absinthii herba). Depending on the herbs, the methods used were more or less suitable. Chemiluminescence measurements showed the smallest differences between untreated and irradiated samples whereas thermoluminescence measurements on isolated minerals from the vegetable drugs gave better results. In some herbs radiation-specific radicals could be identified by ESR spectroscopy. Viscosity measurement is suitable for some herbs as fast and inexpensive method for screening. (orig.) [Deutsch] Die Eignung von Chemilumineszenz-, ESR-, Thermolumineszenz- und Viskositaetsmessungen als Nachweismethode fuer die Behandlung von Arzneidrogen mit ionisierenden Strahlen wurde an Anis, Baldrianwurzel, Baerentraubenblaettern, Birkenblaettern, Bockshornsamen, Cayennepfeffer, Faulbaumrinde, Fenchel, Hagebuttenschalen, Huflattichblaettern

  20. Acoustic elliptical cylindrical cloaks

    Institute of Scientific and Technical Information of China (English)

    Ma Hua; Qu Shao-Bo; Xu Zhuo; Wang Jia-Fu

    2009-01-01

    By making a comparison between the acoustic equations and the 2-dimensional (2D) Maxwell equations, we obtain the material parameter equations (MPE) for acoustic elliptical cylindrical cloaks. Both the theoretical results and the numerical results indicate that an elliptical cylindrical cloak can realize perfect acoustic invisibility when the spatial distributions of mass density and bulk modulus are exactly configured according to the proposed equations. The present work is the meaningful exploration of designing acoustic cloaks that are neither sphere nor circular cylinder in shape, and opens up possibilities for making complex and multiplex acoustic cloaks with simple models such as spheres, circular or elliptic cylinders.

  1. A study of the radiation chemistry of poly(chlorotrifluoroethylene) by ESR spectroscopy[Poly(chlorotrifluoroethylene); {gamma}-radiolysis; ESR study; Radicals; G-values

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.J.T. E-mail: hill@chemistry.uq.edu.au; Thurecht, K.J.; Whittaker, A.K

    2003-12-01

    The ESR spectra of poly(chlorotrifluoroethylene) were recorded following {gamma}-radiolysis under vacuum at room temperature and 77 K. The very broad spectrum at 77 K revealed little fine structure with which to identity the radicals formed upon irradiation, but subsequent photobleaching and annealing studies, together with radiolytic studies at higher temperatures, afforded scope for making radical assignments. Both main-chain radicals and a range of chain-end radicals have been identified. The G-values for radical formation were 1.55, 0.36 and 0.32 at 77 K, 273 K and room temperature, respectively.

  2. ESR investigation of the oxidative damage in lungs caused by asbestos and air pollution particles

    Science.gov (United States)

    Kadiiska, M. B.; Ghio, A. J.; Mason, R. P.

    2004-05-01

    Exposure to asbestos and air pollution particles can be associated with increased human morbidity and mortality. However, the molecular mechanism of lung injuries remains unknown. It has been postulated that the in vivo toxicity results from the catalysis of free radical generation. Using electron spin resonance (ESR) in conjunction with the spin trap α-(4-pyridyl-1-oxide)- N- tert-butylnitrone (4-POBN) we previously investigated in vivo free radical production by rats treated with intratracheal instillation of asbestos (crocidolite fibers) and an emission source air pollution particle (oil fly ash). In this report we compare the effect of two different exposures on the type of free radicals they induce in in vivo animal model. Twenty-four hours after the exposure, ESR spectroscopy of the chloroform extract from lungs of animals exposed to either asbestos or oil fly ash gave a spectrum consistent with a carbon-centered radical adduct ( aN=15.01 G and aH=2.46 G). To test whether free radical formation occurred in vivo and not in vitro, a number of control experiments were performed. Combinations (both individually and together) of asbestos or oil fly ash and 4-POBN were added to lung homogenate of unexposed rats prior to chloroform extraction. No detectable ESR signal resulted. To exclude the possibility of ex vivo free radical generation, asbestos or oil fly ash was added to lung homogenate of an animal treated with 4-POBN. Also, 4-POBN was added to lung homogenate from rats instilled with asbestos or oil fly ash. Neither system produced radical adducts, indicating that the ESR signal detected in the lung extracts of the treated animals must be produced in vivo and not ex vivo or in vitro. In conclusion, ESR analysis of lung tissue demonstrated that both exposures produce lipid-derived radical metabolites despite their different composition and structure. Analogously, both exposures provide evidence of in vivo enhanced lipid peroxidation. Furthermore, it is

  3. ESR and EISCAT observations of the response of the cusp and cleft to IMF orientation changes

    Directory of Open Access Journals (Sweden)

    I. W. McCrea

    Full Text Available We report observations of the cusp/cleft ionosphere made on December 16th 1998 by the EISCAT (European incoherent scatter VHF radar at Tromsø and the EISCAT Svalbard radar (ESR. We compare them with observations of the dayside auroral luminosity, as seen by meridian scanning photometers at Ny Ålesund and of HF radar backscatter, as observed by the CUTLASS radar. We study the response to an interval of about one hour when the interplanetary magnetic field (IMF, monitored by the WIND and ACE spacecraft, was southward. The cusp/cleft aurora is shown to correspond to a spatially extended region of elevated electron temperatures in the VHF radar data. Initial conditions were characterised by a northward-directed IMF and cusp/cleft aurora poleward of the ESR. A strong southward turning then occurred, causing an equatorward motion of the cusp/cleft aurora. Within the equatorward expanding, southward-IMF cusp/cleft, the ESR observed structured and elevated plasma densities and ion and electron temperatures. Cleft ion fountain upflows were seen in association with elevated ion temperatures and rapid eastward convection, consistent with the magnetic curvature force on newly opened field lines for the observed negative IMF By. Subsequently, the ESR beam remained immediately poleward of the main cusp/cleft and a sequence of poleward-moving auroral transients passed over it. After the last of these, the ESR was in the polar cap and the radar observations were characterised by extremely low ionospheric densities and downward field-aligned flows. The IMF then turned northward again and the auroral oval contracted such that the ESR moved back into the cusp/cleft region. For the poleward-retreating, northward-IMF cusp/cleft, the convection flows were slower, upflows were weaker and the electron density and temperature enhancements were less structured. Following the northward turning, the bands of high electron temperature and cusp

  4. ACOUSTICAL STANDARDS NEWS.

    Science.gov (United States)

    Stremmel, Neil; Struck, Christopher J

    2016-07-01

    American National Standards (ANSI Standards) developed by Accredited Standards Committees S1, S2, S3, S3/SC 1, and S12 in the areas of acoustics, mechanical vibration and shock, bioacoustics, animal bioacoustics, and noise, respectively, are published by the Acoustical Society of America (ASA). In addition to these standards, ASA publishes a catalog of Acoustical American National Standards. To receive a copy of the latest Standards catalog, please contact Neil Stremmel.Comments are welcomed on all material in Acoustical Standards News.This Acoustical Standards News section in JASA, as well as the National Catalog of Acoustical Standards and other information on the Standards Program of the Acoustical Society of America, are available via the ASA home page: http://acousticalsociety.org. PMID:27475185

  5. Acoustic streaming in microchannels

    DEFF Research Database (Denmark)

    Tribler, Peter Muller

    , the acoustic streaming flow, and the forces on suspended microparticles. The work is motivated by the application of particle focusing by acoustic radiation forces in medical, environmental and food sciences. Here acoustic streaming is most often unwanted, because it limits the focusability of particles...... work. Based on first- and second-order perturbation theory, assuming small acoustic amplitudes, we derived the time-dependent governing equations under adiabatic conditions. The adiabatic first- and second-order equations are solved analytically for the acoustic field between two orthogonally......-of-the-art in the field. Furthermore, the analytical solution for the acoustic streaming in rectangular channels with arbitrary large height-to-width ratios is derived. This accommodates the analytical theory of acoustic streaming to applications within acoustofluidics....

  6. ESR study of Co-doped TiO2 thin films

    International Nuclear Information System (INIS)

    Co:TiO2 thin films prepared by reactive co-sputtering deposition were studied by electron spin resonance (ESR) technique. Magnetization measurements showed hysteretic behavior with the coercive field between 55 and 65 Oe and the saturation magnetization at room temperature ranging from 7 (2.2% Co) to 28 emu/cm3 (8.5% Co). ESR measurements at X-band (9.5 GHz) revealed an anomaly in the temperature behavior of the absorption intensity near the temperature at 60 K. This behavior is attributed to an unconventional spin-glass-like behavior, which results from competition of long-range dipole-dipole interaction and anisotropy fields in ferromagnetic Co nanoparticles

  7. Changes in molecular structure and properties of irradiated polymers of different compositions - ESR and NMR study

    International Nuclear Information System (INIS)

    Investigations of molecular structural changes in polymers during exposure to high energy radiation is the long term interest of the Polymer Materials and Radiation Group at the University of Queensland. Recently, the group had looked at a range of polymers including natural and synthetic rubbers, methacrylates and polyesters. The objective of the work has been to investigate the relationships between polymer structure and sensitivity towards high energy radiation, including gamma radiation. This report will focus on the Electron Spin Resonance (ESR) and Nuclear Magnetic Resonance (NMR) studies of the effects of gamma irradiation on these polymers. Other methods such as Gas Chromatography (GC), Gel Permeation Chromatography (GPC), Fourier Transformed Infra Red (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Dynamic Mechanical Analysis (DMA) have also been used as these methods combine with ESR and NMR, to provide a more complete picture of the mechanism of the structural changes. (author)

  8. ESR dating of an ancient goat tooth from Nuoro, Sardinia, Italy

    International Nuclear Information System (INIS)

    The dating of fossil teeth of an ancient goat (Nesogoral melonii) using the electron spin resonance (ESR) technique is reported. This animal was found in the fossiliferous site at Orosei (Nuoro, Sardinia, Italy) and was endemic in the region. Molar teeth were cleaned and enamel was completely removed from dentine. Enamel was irradiated with a 60Co gamma source and measured with an ESR spectrometer (X-band) to obtain the signal vs. dose curve and fitted with an exponential function. The archaeological dose obtained by the fitting was 211 ± 34 Gy. Uranium and thorium concentrations were determined by neutron activation analysis. With the software ROSY the age estimates were 195 ± 30 ky for early uptake, 247 ± 40 ky for linear uptake and 243 ± 40 ky for a combination of uptake processes. (authors)

  9. TL and ESR based identification of gamma-irradiated frozen fish using different hydrolysis techniques

    Science.gov (United States)

    Ahn, Jae-Jun; Akram, Kashif; Shahbaz, Hafiz Muhammad; Kwon, Joong-Ho

    2014-12-01

    Frozen fish fillets (walleye Pollack and Japanese Spanish mackerel) were selected as samples for irradiation (0-10 kGy) detection trials using different hydrolysis methods. Photostimulated luminescence (PSL)-based screening analysis for gamma-irradiated frozen fillets showed low sensitivity due to limited silicate mineral contents on the samples. Same limitations were found in the thermoluminescence (TL) analysis on mineral samples isolated by density separation method. However, acid (HCl) and alkali (KOH) hydrolysis methods were effective in getting enough minerals to carry out TL analysis, which was reconfirmed through the normalization step by calculating the TL ratios (TL1/TL2). For improved electron spin resonance (ESR) analysis, alkali and enzyme (alcalase) hydrolysis methods were compared in separating minute-bone fractions. The enzymatic method provided more clear radiation-specific hydroxyapatite radicals than that of the alkaline method. Different hydrolysis methods could extend the application of TL and ESR techniques in identifying the irradiation history of frozen fish fillets.

  10. The application of Alanine/ESR dosimetry in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hoon; Lee, Byung Il [Radiation Health Research Institute, Seoul (Korea, Republic of)

    2014-05-15

    Alanine/Electron spin resonance(ESR) has been proven very effective tool which dosimetric characteristics is better suitable than generally used personnel dosimeter for long term dose estimation. L-α-alanine has unusual stability of radiation induced radicals. The fading is known as about 1% a year by IAEA technical documentary. It also has linear signal response on gamma rays over the wide range of dose quantity. Alanine is a kind of unnecessary amino acid in 20 amino acids. Estimation of the accumulated gamma dose is important to predict the life expectancy of cables. However, exact estimation of gamma dose at containment building of NPP is very difficult, because the variability of estimation value is apparently depending on the each installation position in containment building. Especially, some installation positions near reactor change extremely. So, the data from ESR measurement should be checked to the details on referring installation map and pictures.

  11. ESR (electron spin resonance)-determined osmotic behavior of bull spermatozoa

    Energy Technology Data Exchange (ETDEWEB)

    Du, J.; Kleinhans, F.W.; Spitzer, V.J.; Critser, J.K. (Methodist Hospital, Indianapolis, IN (USA). Dept. of Medical Research); Horstman, L. (Purdue Univ., Lafayette, IN (USA). School of Veterinary Medicine); Mazur, P. (Oak Ridge National Lab., TN (USA))

    1990-01-01

    Our laboratories are pursuing a fundamental approach to the problems of semen cryopreservation. For many cell types (human red cells, yeast, HeLa) it has been demonstrated that there is an optimum cooling rate for cryopreservation. Faster rates allow insufficient time for cell dehydration and result in intracellular ice formation and cell death. It is possible to predict this optimal rate provided that the cell acts as an ideal osmometer and several other cell parameters are known such as the membrane hydraulic conductivity. It is the purpose of this work to examine the osmotic response of bull sperm to sucrose and NaCl utilizing electron spin resonance (ESR) to measure cell volume. For calibration purposes we also measured the ESR response of human red cells (RBC), the osmotic response of which is well documented with other methods. 15 refs., 1 fig.

  12. Sediment U, Th, K content analyzed using X-ray fluorescence spectrometry for ESR dating samples

    International Nuclear Information System (INIS)

    The accurate measurement of dose rate is the key issues to obtain reliable ESR age. In this article, we used X-ray fluorescence spectrometry to determine the U, Th, K content of the fluvial sediments. And the standard working curves were established using the national rock reference material. Setting the lower X-ray power and the matrix effect, U, Th, K content in the fluvial sediment were investigated. The results show that the method recovery rate of U and Th is less than 15%. Comparing with the measurement data from the α-counting and Atomic Spectrometry analysis, the dose rate difference is less than 5%. It shows that the X-ray fluorescence spectrometry method can fit for the requirement for obtaining the U, Th, K content of fluvial sediment for ESR dating. (authors)

  13. ESR Dosimetry for Atomic Bomb Survivors Using Shell Buttons and Tooth Enamel

    Science.gov (United States)

    Ikeya, Motoji; Miyajima, Junko; Okajima, Shunzo

    1984-09-01

    Atomic bomb radiation doses to humans at Nagasaki and Hiroshima are investigated by electron spin resonance (ESR) from shell buttons and tooth enamel voluntarily supplied by survivors. A shell button gives a dose of 2.1± 0.2 Gy with ESR signals at g=2.001 and g=1.997 while the signal at g=1.997 for the tooth enamel of the same person is 1.9± 0.5 Gy. Other teeth show doses from about 0.5 Gy to 3 Gy. An apparent shielding converted to a concrete thickness is given using the T65D calculated in 1965. Teeth extracted during dental treatment should be preserved for cumulative radiation dosimetry.

  14. Uses of polymer-alanine film/ESR dosimeters in dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Alanine ESR dosimetry is a reliable method, used in a various fields of ionizing radiation. The polymer-alanine film/ESR dosimeters of 0.3 -0.4 mm thickness were prepared and their dosimetric properties were studied for 60Co γ photons and 3 - 5 MeV electrons in the dose range from 20 Gy to 100 kGy. The results show that under normal conditions the alanine calibration curves are linear in the dose range from 100 Gy to 10kGy. The dose profiles at the electron radiation field were measured with the film alanine dosimeters. The polymer-alanine film dosimeters were used for ion implantation of 400 keV ion implantor. Their dose response and energy dependence were investigated initially. (Author)

  15. ESR and spectral studies of Er3+ ions in soda-lime silicate glass

    International Nuclear Information System (INIS)

    Electron spin resonance (ESR), optical absorption spectra and photoluminescence spectra of Er3+ ions in soda-lime silicate glasses doped with different concentrations of Er2O3 have been studied. The glasses of the composition (in mol%) (65-x)SiO2:25Na2O:10CaO:xEr2O3 (where x=0.02, 0.05, 0.1, 0.3, 0.5, 1, 2, 3, 4 and 5) were prepared by the melt quenching method. ESR measurements were carried out at room temperature down to 1.62 K. Absorption spectra were investigated in the UV-VIS-NIR region from 300 to 1800 nm. Photoluminescence spectra were observed in the spectral range 500-800 nm under 514.5 nm argon-ion laser line excitation.

  16. ESR study of advanced materials with new parameters frequency and pressure

    CERN Document Server

    Mizoguchi, K

    2000-01-01

    It is well known that electron spin resonance (ESR) is a useful technique to investigate the magnetic properties of electrons in condensed matter. The frequency, as an additional parameter to the temperature, gives us the possibility to study the anisotropic dynamics of charge carriers with spin, even in polycrystalline materials. Furthermore, the pressure provides us a way to discuss how interactions between the electrons and their environments are responsible for the novel physical properties in these advanced materials, such as ferromagnetisms, charge-density waves, superconductivity, and so on. Results obtained by using ESR with these parameters are overviewed. Studies as a function of the frequency are demonstrated, especially for the conductive polymers, polyacetylene, polyaniline, and polypyrrole with various dopants for which single crystals are not available yet. Alkali-electro-sodalite (AES), a kind of zeolite with a regular electron lattice known as an s-electron Mott insulator, and fullerene compo...

  17. Electron spins in reduced dimensions. ESR spectroscopy on semiconductor heterostructures and spin chain compounds

    Energy Technology Data Exchange (ETDEWEB)

    Lipps, Ferdinand

    2011-08-31

    Spatial confinement of electrons and their interactions as well as confinement of the spin dimensionality often yield drastic changes of the electronic and magnetic properties of solids. Novel quantum transport and optical phenomena, involving electronic spin degrees of freedom in semiconductor heterostructures, as well as a rich variety of exotic quantum ground states and magnetic excitations in complex transition metal oxides that arise upon such confinements, belong therefore to topical problems of contemporary condensed matter physics. In this work electron spin systems in reduced dimensions are studied with Electron Spin Resonance (ESR) spectroscopy, a method which can provide important information on the energy spectrum of the spin states, spin dynamics, and magnetic correlations. The studied systems include quasi onedimensional spin chain materials based on transition metals Cu and Ni. Another class of materials are semiconductor heterostructures made of Si and Ge. Part I deals with the theoretical background of ESR and the description of the experimental ESR setups used which have been optimized for the purposes of the present work. In particular, the development and implementation of axial and transverse cylindrical resonant cavities for high-field highfrequency ESR experiments is discussed. The high quality factors of these cavities allow for sensitive measurements on {mu}m-sized samples. They are used for the investigations on the spin-chain materials. The implementation and characterization of a setup for electrical detected magnetic resonance is presented. In Part II ESR studies and complementary results of other experimental techniques on two spin chain materials are presented. The Cu-based material Linarite is investigated in the paramagnetic regime above T>2.8 K. This natural crystal constitutes a highly frustrated spin 1/2 Heisenberg chain with ferromagnetic nearest-neighbor and antiferromagnetic next-nearestneighbor interactions. The ESR data

  18. Irradiation and ESR analysis temperature dependence of the gamma-ray response of alanine-polystyrene dosimeters

    International Nuclear Information System (INIS)

    Response characteristics of the alanine-polystyrene dosimeter were studied at an absorbed dose of 5 kGy over the low irradiation temperature range -196 ∼ 30oC, and the ESR analysis temperature range 0 ∼50oC in the dose range 0.1 ∼ 10 kGy. The irradiation temperature coefficient previously estimated for the temperature range from 0 ∼ 70oC (+0.24%/.oC) was verified down to -15oC, although about 8% lower values were obtained at -78 and -196oC based on the correction using the above coefficient. ESR intensity decreases with temperature during ESR analysis following the function of the reciprocal of absolute temperature based on Boltzmann's constant. The average temperature coefficient for three different dose levels during ESR analysis of the alanine-polystyrene dosimeter is -0.25%/K in the temperature range 0 ∼ 50oC. (Author)

  19. Comparison study of tooth enamel ESR spectra of cows, goats and humans

    OpenAIRE

    Jiao, Ling; Liu, Zhong-Chao; Ding, Yan-Qiu; Ruan, Shu-Zhou; Wu, Quan; FAN, SAI-JUN; Zhang, Wen-Yi

    2014-01-01

    The ESR radiation dosimetric properties of tooth enamel samples from cows and goats were investigated and compared with those of human samples. Samples were prepared first mechanically, and then chemically. The study results showed that the native signals from cow and goat samples were weaker than those from human samples; the radiation sensitivities for cow and goat samples were very close to those of human tooth enamel samples. These results indicated that cow and goat teeth could be altern...

  20. Common genetic variability in ESR1 and EGF in relation to endometrial cancer risk and survival

    OpenAIRE

    Einarsdóttir, K; Darabi, H; Czene, K.; Li, Y; Low, Y.L.; Y. Q. Li; Bonnard, C.; Wedrén, S.; Liu, E. T.; Hall, P; Liu, J; Humphreys, K.

    2009-01-01

    We investigated common genetic variation in the entire ESR1 and EGF genes in relation to endometrial cancer risk, myometrial invasion and endometrial cancer survival. We genotyped a dense set of single-nucleotide polymorphisms (SNPs) in both genes and selected haplotype tagging SNPs (tagSNPs). The tagSNPs were genotyped in 713 Swedish endometrial cancer cases and 1567 population controls and the results incorporated into logistic regression and Cox proportional hazards models. We found five a...

  1. ESR of copper and iron complexes with antitumor and cytotoxic properties.

    OpenAIRE

    Antholine, W E; Kalyanaraman, B.; Petering, D H

    1985-01-01

    The relatively few iron and copper metal complexes which have been examined in cells and tissues for their redox properties, radical generation properties, and antitumor activity are discussed for studies which utilized electron spin resonance spectroscopy (ESR). A common property of a number of metal complexes, which include bleomycin, adriamycin, and thiosemicarbazones described in this review, is that they are readily reduced by thiol compounds and oxidized by oxygen or reduced species of ...

  2. Construction of an ESR-STM for Single Molecular Based Magnets anchored at Surfaces

    OpenAIRE

    Messina, Paolo; Sigalotti, Paolo; Lenci, Lorenzo; Mannini, Matteo; Prato, Stefano; Pittana, Paolo; Gatteschi, Dante

    2004-01-01

    Reading and manipulating the spin status of single magnetic molecules is of paramount importance both for applicative and fundamental purposes. The possibility to combine Electron Spin Resonance (ESR) and Scanning Tunnelling Microscopy (STM) has been explored one decade ago. A few experiments have raised the question whether or not an EPR spectrum of single molecule is detachable. Only a few data have been reported in modern surface science literature. To date it has yet to be proven to which...

  3. Core curriculum for medical physicists in radiology. Recommendations from an EFOMP/ESR working group

    OpenAIRE

    Geleijns, Jacob; Breatnach, Éamann; Cantera, Alfonso Calzado; Damilakis, John; Dendy, Philip; Evans, Anthony; Faulkner, Keith; Padovani, Renato; Van Der Putten, Wil; Schad, Lothar; Wirestam, Ronnie; Eudaldo, Teresa; ,

    2012-01-01

    Some years ago it was decided that a European curriculum should be developed for medical physicists professionally engaged in the support of clinical diagnostic imaging departments. With this in mind, EFOMP (European Federation of Organisations for Medical Physics) in association with ESR (European Society of Radiology) nominated an expert working group. This curriculum is now to hand. The curriculum is intended to promote best patient care in radiology departments through the harmonization o...

  4. E layer dominated ionosphere observed by EISCAT/ESR radars during solar minimum

    OpenAIRE

    Cai, Hongtao; Li, Fei; Shen, Ge; Zhan, Weijia; Zhou, Kangjun; McCrea, Ian Willian; Ma, Shuying

    2014-01-01

    According to the study by Mayer and Jakowski (2009), periods of E layer dominated ionosphere (ELDI) are defined as being characterized by vertical electron density profiles having a maximum density at E layer altitudes. In this paper, characteristics of ELDI intervals have been investigated, focusing on their temporal variations, using field-aligned measurements from the EISCAT and ESR radars during the interval 2009–2011. ELDI events were identified using simple but reasona...

  5. ESR of an O/sub 3//sup -/ centre in KCl

    Energy Technology Data Exchange (ETDEWEB)

    Callens, F.; Matthys, P.; Boesman, E.

    1988-06-20

    By means of ESR an ozonide molecular O/sub 3//sup -/ ion was detected in x-irradiated KCl. The principal values of the G-tensor (2.0032, 2.0182, 2.0118) are in excellent agreement with the values found in other host lattices and with CNDO calculations performed earlier. All measurements were carried out at liquid-helium temperatures.

  6. Dosimetry for radiation processing of wire insulations by using the alanine/ESR system

    International Nuclear Information System (INIS)

    The wire insulation can be simulated by an alanine-based dosimeter, i.e. by a polymer containing L-α-alanine. If this system is properly calibrated against a reliable reference dosimeter, it can be used to determine the absorbed dose in the wire insulation, irradiated on an industrial line for electron-beam crosslinking of wire insulations. The evaluation is achieved by ESR spectroscopy. (author) 13 refs.; 3 figs

  7. The ESR/alanine dosimeter - power dependence of the X-band spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Arber, J.M.; Sharpe, P.H.G. (National Physical Lab., Teddington (UK)); Joly, H.A.; Morton, J.R.; Preston, K.F. (National Research Council, Ottawa (Canada). Steacie Inst. for Molecular Sciences)

    1991-01-01

    Satellite lines which accompany the central feature of the X-band ESR spectrum of {alpha}-alanine dosimeters are shown to be due to forbidden ''spin-flip'' transitions associated with methyl protons on nearby molecules. At microwave powers in excess of 1 mW the satellites increase in intensity relative to the central feature, and thus measurements at higher microwave powers must be based on experimentally determined calibration curves at the appropriate power levels. (author).

  8. Free radical reaction in ischemic rat brain. ESR-CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kayama, Takamasa [Yamagata Univ. (Japan). School of Medicine

    1998-07-01

    Free radical change in images of rat brain during brain ischemia was observed by using a rapid scan L-band ESR-CT system. Male Wistar rats weighing 200 g were used. Rats were divided into three groups according to the duration of occlusion of 2, 4, and 8 hr as well as a control, sham-operated group. C-PROXYL dissolved in saline solution was used as an imaging agent and injected intraperitoneally in a volume of 3 ml at a concentration of 0.3 M at the beginning of reperfusion. ESR-CT imaging was performed 20 min after injection of C-PROXYL. In the sham-operated group, histological examination disclosed no ischemic lesion. Because C-PROXYL does not pass the blood-brain barrier, no brain image was obtained. In the 2 hr occlusion ischemic group, histological findings revealed spongioid change at the dorsal putamen. The ESR-CT image showed a small spot of uptake of nitroxide radicals in the area of the presumed left putamen which corresponded to the histological ischemic lesion. In the 8 hr occlusion group, the ischemic lesion was found even in the cerebral cortex. The image of nitroxide radical in the brain again closely corresponded to the histological ischemic area and occupied most of the left cerebral hemisphere. However, the area of ESR-CT image was wider than that of histological ischemic lesion. This may be because C-PROXYL leakage in the ischemic lesion diffuses and also because the extent of the efficiency of scavenging free radicals may decline. (K.H.)

  9. Droplet digital polymerase chain reaction assay for screening of ESR1 mutations in 325 breast cancer specimens.

    Science.gov (United States)

    Takeshita, Takashi; Yamamoto, Yutaka; Yamamoto-Ibusuki, Mutsuko; Inao, Toko; Sueta, Aiko; Fujiwara, Saori; Omoto, Yoko; Iwase, Hirotaka

    2015-12-01

    Droplet digital polymerase chain reaction (ddPCR), which could perform thousands of PCRs on a nanoliter scale simultaneously, would be an attractive method to massive parallel sequencing for identifying and studying the significance of low-frequency rare mutations. Recent evidence has shown that the key potential mechanisms of the failure of aromatase inhibitors-based therapy involve identifying activating mutations affecting the ligand-binding domain of the ESR1 gene. Therefore, the detection of ESR1 mutations may be useful as a biomarker predicting an effect of the treatment. We aimed to develop a ddPCR-based method for the sensitive detection of ESR1 mutations in 325 breast cancer specimens, in which 270 primary and 55 estrogen receptor-positive (ER+) metastatic breast cancer (MBC) specimens. Our ddPCR assay could detect the ESR1 mutant molecules with low concentration of 0.25 copies/μL. According to the selected cutoff, ESR1 mutations occurred in 7 (2.5%) of 270 primary breast cancer specimens and in 11 (20%) of 55 ER+ MBC specimens. Among the 11 MBC specimens, 5 specimens (45.5%) had the most common ESR1 mutation, Y537S, 4 specimens (36.3%) each had D538G, Y537N, and Y537C. Interestingly, 2 patients had 2 ESR1 mutations, Y537N/D538G and Y537S/Y537C, and 2 patients had 3 ESR1 mutations, Y537S/Y537N/D538G. Biopsy was performed in heterochrony in 8 women twice. In 8 women, 4 women had primary breast cancer and MBC specimens and 4 women had 2 specimens when treatment was failure. Four of these 8 women acquired ESR1 mutation, whereas no ESR1 mutation could be identified at first biopsy. ddPCR technique could be a promising tool for the next-generation sequencing-free precise detection of ESR1 mutations in endocrine therapy resistant cases and may assist in determining the treatment strategy.

  10. Analysis of parameters that influence the amplitude of the ESR/alanine signal after irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Dolo, J.M. [BNM-Laboratoire National Henri Becquerel, CEA-Saclay, DIMRI/LNHB, 91191 Gif-sur-Yvette cedex (France)]. E-mail: jean-michel.dolo@cea.fr; Feaugas, V. [BNM-Laboratoire National Henri Becquerel, CEA-Saclay, DIMRI/LNHB, 91191 Gif-sur-Yvette cedex (France)

    2005-02-01

    When ESR/alanine dosimetry is used for comparison, the time elapsed between irradiation and measurement is critical. Several publications have already mentioned the need for monitoring some of the parameters before, during and after irradiation for accurate normalization of ESR measurements. Nevertheless, neither classification nor coupling effects have yet been mentioned. By application of an experimental design approach, some parameters such as temperature and humidity during storage, before and after irradiation, have been studied. Results are given about the way the signal tends to evolve, ranking the parameters according to their influence and the effects of parameter coupling. A comparison with a conventional approach (study of one parameter at a time) is made. It is proposed to use a normalized ESR measurement that better accounts for the chemical aspect. A better fit of the results (amplitude versus time) is observed when amplitude is corrected taking into account the water content of the dosimeter for a given relative humidity of the surrounding atmosphere during storage.

  11. Analysis of parameters that influence the amplitude of the ESR/alanine signal after irradiation.

    Science.gov (United States)

    Dolo, J M; Feaugas, V

    2005-02-01

    When ESR/alanine dosimetry is used for comparison, the time elapsed between irradiation and measurement is critical. Several publications have already mentioned the need for monitoring some of the parameters before, during and after irradiation for accurate normalization of ESR measurements. Nevertheless, neither classification nor coupling effects have yet been mentioned. By application of an experimental design approach, some parameters such as temperature and humidity during storage, before and after irradiation, have been studied. Results are given about the way the signal tends to evolve, ranking the parameters according to their influence and the effects of parameter coupling. A comparison with a conventional approach (study of one parameter at a time) is made. It is proposed to use a normalized ESR measurement that better accounts for the chemical aspect. A better fit of the results (amplitude versus time) is observed when amplitude is corrected taking into account the water content of the dosimeter for a given relative humidity of the surrounding atmosphere during storage. PMID:15607461

  12. Analysis of parameters that influence the amplitude of the ESR/alanine signal after irradiation

    International Nuclear Information System (INIS)

    When ESR/alanine dosimetry is used for comparison, the time elapsed between irradiation and measurement is critical. Several publications have already mentioned the need for monitoring some of the parameters before, during and after irradiation for accurate normalization of ESR measurements. Nevertheless, neither classification nor coupling effects have yet been mentioned. By application of an experimental design approach, some parameters such as temperature and humidity during storage, before and after irradiation, have been studied. Results are given about the way the signal tends to evolve, ranking the parameters according to their influence and the effects of parameter coupling. A comparison with a conventional approach (study of one parameter at a time) is made. It is proposed to use a normalized ESR measurement that better accounts for the chemical aspect. A better fit of the results (amplitude versus time) is observed when amplitude is corrected taking into account the water content of the dosimeter for a given relative humidity of the surrounding atmosphere during storage

  13. ESR (Electronic Spin Resonance Spectroscopy) study of irradiated paper for biomedical material wrapping

    International Nuclear Information System (INIS)

    Ionising radiation treatments are used for sterilization, microbiological decontamination, disinfection, insect disinfestation and food preservation. This ionising radiation generates free radicals (FR) in matter, which can be detected by Electronic Spin Resonance Spectroscopy (ESR). For this work it had analysed different kind of irradiated package papers of syringes, surgical gloves and dressings by ESR. These were irradiated with doses between 20 and 35 kGy of gamma radiation (Cobalt 60). The processed samples were measured in a Bruker ECS 106 spectrometer. The obtained results were: 1-) The irritated samples showed a central peak and two satellites induced by the applied radiation; 2-) The non-irradiated samples did not show the characteristic satellite peaks of the irritated ones; 3-) A linear relationship between the signal heights per unit mass and the applied doses was found; and 4-) The signals were highly stable, with half-time values between 240 and 370 days for 20 and 30 kGy, permitting more than one year of monitoring proceedings. In conclusion, the ESR allows the detection, quantification and time monitoring processes of this kind of irradiated materials. (author)

  14. ESR studies on Er sup 3 sup + -doped YBiPt compound

    CERN Document Server

    Guener, S; Aktas, B

    2003-01-01

    The semi-metallic cubic compound YBiPt doped by Er sup 3 sup + (4f sup 1 sup 1) has been studied by ESR technique between 4 and 300 K. X-band and Q-band measurements have been performed. The angular dependence of the ESR spectra on the crystal orientation with respect to the static magnetic field has been measured. Two anisotropic lines with hyperfine peaks coming from the interaction between electronic and nuclear spins of sup 1 sup 6 sup 7 Er sup 3 sup + (I=7/2) isotopes have been observed below 30 K in the spectra. Computer modeling showed that these lines are the ESR signals from the quadruplet ground state of Er sup 3 sup + ions in the cubic crystal field. The values of crystal field parameters B sub 4 =-5.68 x 10 sup - sup 4 cm sup - sup 1 and B sub 6 =-6.64 x 10 sup - sup 6 cm sup - sup 1 have been extracted. Also an isotropic line near g=2 have been observed in both frequency bands. Dysonian lineshape of the spectra components due to the skin-depth effect shows the conducting property of the sample un...

  15. TL and ESR based identification of gamma-irradiated frozen fish using different hydrolysis techniques

    International Nuclear Information System (INIS)

    Frozen fish fillets (walleye Pollack and Japanese Spanish mackerel) were selected as samples for irradiation (0–10 kGy) detection trials using different hydrolysis methods. Photostimulated luminescence (PSL)-based screening analysis for gamma-irradiated frozen fillets showed low sensitivity due to limited silicate mineral contents on the samples. Same limitations were found in the thermoluminescence (TL) analysis on mineral samples isolated by density separation method. However, acid (HCl) and alkali (KOH) hydrolysis methods were effective in getting enough minerals to carry out TL analysis, which was reconfirmed through the normalization step by calculating the TL ratios (TL1/TL2). For improved electron spin resonance (ESR) analysis, alkali and enzyme (alcalase) hydrolysis methods were compared in separating minute-bone fractions. The enzymatic method provided more clear radiation-specific hydroxyapatite radicals than that of the alkaline method. Different hydrolysis methods could extend the application of TL and ESR techniques in identifying the irradiation history of frozen fish fillets. - Highlights: • Irradiation has potential to improve hygienic quality of raw and processed seafood. • Detection of irradiated food is important to enforce the applied regulations. • Different techniques were compared to separate silicate minerals from frozen fish. • Limitations were observed in TL analysis on minerals isolated by density separation. • Hydrolysis methods provided more clear identification using TL and ESR techniques

  16. Pulse radiolysis studies of short-lived species in solid amino acids as precursors of radicals and detected by ESR

    Science.gov (United States)

    Zagórski, Z. P.; Gładysz, Katarzyna

    1995-06-01

    The aim of the study was to bring closer solid state radiation chemistry and ESR spectroscopy by looking for precursors of free radicals which give ESR signals. It has been performed using time-resolved spectrophotometry (pulse radiolysis of the solid state) and diffuse reflection spectrophotometry. Alanine has been especially considered as the most investigated amino acid, important for radiation dosimetry. Absorption of the transient (Λ maximum at 460 nm) is identified as the species during deamination. The stable absorption spectrum with the Λ maximum at 345 nm is due to the same radical as the one detected by ESR. Other amino acids: valine, threonine, glutamine and arginine show similar behaviour: microsecond spectrum of the intermediate appears always at longer wavelenghts. The transient spectrum changes into stable absorption in UV of a lower wavelenght. Along with the optical spectrum, the ESR spectrum appears, of similar stability. Also, other features indicate that the same radical is responsible for both the electronic and ESR spectrum. Some amino acids, like methionine give intensive transient absorption in the microsecond range but no ESR signal, after completion of consecutive fast reactions. In that case any optical absorption is due to the stable product of radiolysis, i.e. compounds with paired electrons only.

  17. The combined genotypes effe- ct of ESR and FSHb genes on litter size traits in five differe- nt pig breeds

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Estrogen receptor (ESR) and Follicular-stimula- ting hormone beta subunit (FSHb) genes were chosen as candidates to determine whether they control litter size and some other reproductive traits in swine. 269 sows from five different pig breeds were genotyped by an established PCR- RFLPs protocol at both ESR and FSHb loci. The effects of both ESR and FSHb on pig reproductive traits, including total number born (TNB) and number born alive (NBA), are analyzed by SAS software (version 6.12). These computation results demonstrated that both ESR locus and FSHb locus are the major genes influencing litter size in pigs. The sows of BBBB combined genotype of ESR and FSHb loci generally produce 1.85-3.01 TNB and 2.0-3.0 NBA more than those of ABAA combined genotype. The notable effect of ESR locus and FSHb locus on litter size of pigs have made it possible to improve the pig reproduction by Marker-assisted selection (MAS). Moreover, introgression of the beneficial alleles into commercial pig breeding lines, in which the alleles were not present, will improve greatly the economically imp- ortant reproductive traits and efficiency of pig production.

  18. Springer handbook of acoustics

    CERN Document Server

    2014-01-01

    Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience, and electronics. The Springer Handbook of Acoustics is also in his 2nd edition an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents. This new edition of the Handbook features over 11 revised and expanded chapters, new illustrations, and 2 new chapters covering microphone arrays  and acoustic emission.  Updated chapters contain the latest research and applications in, e.g. sound propagation in the atmosphere, nonlinear acoustics in fluids, building and concert hall acoustics, signal processing, psychoacoustics, computer music, animal bioacousics, sound intensity, modal acoustics as well as new chapters on microphone arrays an...

  19. Vibro-acoustics

    CERN Document Server

    Nilsson, Anders

    2015-01-01

    This three-volume book gives a thorough and comprehensive presentation of vibration and acoustic theories. Different from traditional textbooks which typically deal with some aspects of either acoustic or vibration problems, it is unique of this book to combine those two correlated subjects together. Moreover, it provides fundamental analysis and mathematical descriptions for several crucial phenomena of Vibro-Acoustics which are quite useful in noise reduction, including how structures are excited, energy flows from an excitation point to a sound radiating surface, and finally how a structure radiates noise to a surrounding fluid. Many measurement results included in the text make the reading interesting and informative. Problems/questions are listed at the end of each chapter and the solutions are provided. This will help the readers to understand the topics of Vibro-Acoustics more deeply. The book should be of interest to anyone interested in sound and vibration, vehicle acoustics, ship acoustics and inter...

  20. ESR based detection method for irradiated dry fish, tomato soup powder and sweet-meats

    International Nuclear Information System (INIS)

    Full text: Radiation Processing is increasingly being accepted as one of the most effective and economic method to treat agricultural and horticultural commodities for hygienization and disinfestation purposes and also in overcoming strict quarantine barriers in international trade. At present there is a growing concern about the presence of insecticides and pesticides and their residues in various foods, we consume. In view of this, irradiation, being a physical and cold process, emerges as the best bet towards having an uninterrupted supply of safe and quality food. The process has been endorsed as safe by several international and national bodies. A suitable detection method is however required to meet the basic requirements of consumers and law enforcement authorities, regulating the trade. Dried, sliced Pollack and File fishes were subjected to radiation dose of 4 kGy for elimination of coliforms and for improvement in quality standards during storage. Bones separated served as sample source for ESR based detection method of the radiation treatment. Bones with hard crystalline matrix served as trap for free radicals and facilitated evolution of an ESR based detection method. It showed a linear dose response curve at γ=2.0037, whereas, those from non-irradiated fish fillets failed to show any ESR signal. Re-irradiation helped in calculation of dose delivered to dried fishes. Sachets -containing tomato soup ingredients, including sugars exposed to 0.25 to 2 kGy gamma radiation doses for hygienization and quarantine purposes were used in the experiments. In-pack sugar crystals served as free radicals trap for ESR based detection method for radiation hygienized tomato soup powder. Similarly, it was observed that radiation hygienization of sugar bearing sweet-meats, like Peda (an evaporated milk preparation), Petha (a sugar syrup soaked vegetable preparation) and dry fruits like raisins could be detected using ESR. Suitable methodology was developed to detect

  1. Shallow Water Acoustic Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Supports experimental research where high-frequency acoustic scattering and surface vibration measurements of fluid-loaded and non-fluid-loaded structures...

  2. Low frequency acoustic microscope

    Science.gov (United States)

    Khuri-Yakub, Butrus T.

    1986-11-04

    A scanning acoustic microscope is disclosed for the detection and location of near surface flaws, inclusions or voids in a solid sample material. A focused beam of acoustic energy is directed at the sample with its focal plane at the subsurface flaw, inclusion or void location. The sample is scanned with the beam. Detected acoustic energy specularly reflected and mode converted at the surface of the sample and acoustic energy reflected by subsurface flaws, inclusions or voids at the focal plane are used for generating an interference signal which is processed and forms a signal indicative of the subsurface flaws, inclusions or voids.

  3. Handbook of Engineering Acoustics

    CERN Document Server

    Möser, Michael

    2013-01-01

    This book examines the physical background of engineering acoustics, focusing on empirically obtained engineering experience as well as on measurement techniques and engineering methods for prognostics. Its goal is not only to describe the state of art of engineering acoustics but also to give practical help to engineers in order to solve acoustic problems. It deals with the origin, the transmission and the methods of the abating different kinds of air-borne and structure-borne sounds caused by various mechanisms – from traffic to machinery and flow-induced sound. In addition the modern aspects of room and building acoustics, as well as psychoacoustics and active noise control, are covered.

  4. Localized acoustic surface modes

    Science.gov (United States)

    Farhat, Mohamed; Chen, Pai-Yen; Bağcı, Hakan

    2016-04-01

    We introduce the concept of localized acoustic surface modes. We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  5. Localized Acoustic Surface Modes

    KAUST Repository

    Farhat, Mohamed

    2015-08-04

    We introduce the concept of localized acoustic surface modes (ASMs). We demonstrate that they are induced on a two-dimensional cylindrical rigid surface with subwavelength corrugations under excitation by an incident acoustic plane wave. Our results show that the corrugated rigid surface is acoustically equivalent to a cylindrical scatterer with uniform mass density that can be represented using a Drude-like model. This, indeed, suggests that plasmonic-like acoustic materials can be engineered with potential applications in various areas including sensing, imaging, and cloaking.

  6. What Is an Acoustic Neuroma

    Science.gov (United States)

    ... org Connect with us! What is an Acoustic Neuroma? Each heading slides to reveal information. Important Points ... Neuroma Important Points To Know About an Acoustic Neuroma An acoustic neuroma, also called a vestibular schwannoma, ...

  7. Predicting Acoustics in Class Rooms

    DEFF Research Database (Denmark)

    Christensen, Claus Lynge; Rindel, Jens Holger

    2005-01-01

    Typical class rooms have fairly simple geometries, even so room acoustics in this type of room is difficult to predict using today's room acoustic computer modeling software. The reasons why acoustics of class rooms are harder to predict than acoustics of complicated concert halls might be explai......Typical class rooms have fairly simple geometries, even so room acoustics in this type of room is difficult to predict using today's room acoustic computer modeling software. The reasons why acoustics of class rooms are harder to predict than acoustics of complicated concert halls might...... with surface scattering is presented. Each of the two scattering effects is modeled as frequency dependent functions....

  8. Ocean acoustic reverberation tomography.

    Science.gov (United States)

    Dunn, Robert A

    2015-12-01

    Seismic wide-angle imaging using ship-towed acoustic sources and networks of ocean bottom seismographs is a common technique for exploring earth structure beneath the oceans. In these studies, the recorded data are dominated by acoustic waves propagating as reverberations in the water column. For surveys with a small receiver spacing (e.g., ocean acoustic reverberation tomography, is developed that uses the travel times of direct and reflected waves to image ocean acoustic structure. Reverberation tomography offers an alternative approach for determining the structure of the oceans and advancing the understanding of ocean heat content and mixing processes. The technique has the potential for revealing small-scale ocean thermal structure over the entire vertical height of the water column and along long survey profiles or across three-dimensional volumes of the ocean. For realistic experimental geometries and data noise levels, the method can produce images of ocean sound speed on a smaller scale than traditional acoustic tomography.

  9. Acoustic Signals and Systems

    DEFF Research Database (Denmark)

    2008-01-01

    The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook...... will present topics on signal processing which are important in a specific area of acoustics. These will be of interest to specialists in these areas because they will be presented from their technical perspective, rather than a generic engineering approach to signal processing. Non-specialists, or specialists...... from different areas, will find the self-contained chapters accessible and will be interested in the similarities and differences between the approaches and techniques used in different areas of acoustics....

  10. Ocean acoustic hurricane classification.

    Science.gov (United States)

    Wilson, Joshua D; Makris, Nicholas C

    2006-01-01

    Theoretical and empirical evidence are combined to show that underwater acoustic sensing techniques may be valuable for measuring the wind speed and determining the destructive power of a hurricane. This is done by first developing a model for the acoustic intensity and mutual intensity in an ocean waveguide due to a hurricane and then determining the relationship between local wind speed and underwater acoustic intensity. From this it is shown that it should be feasible to accurately measure the local wind speed and classify the destructive power of a hurricane if its eye wall passes directly over a single underwater acoustic sensor. The potential advantages and disadvantages of the proposed acoustic method are weighed against those of currently employed techniques. PMID:16454274

  11. Cochlear bionic acoustic metamaterials

    Science.gov (United States)

    Ma, Fuyin; Wu, Jiu Hui; Huang, Meng; Fu, Gang; Bai, Changan

    2014-11-01

    A design of bionic acoustic metamaterial and acoustic functional devices was proposed by employing the mammalian cochlear as a prototype. First, combined with the experimental data in previous literatures, it is pointed out that the cochlear hair cells and stereocilia cluster are a kind of natural biological acoustic metamaterials with the negative stiffness characteristics. Then, to design the acoustic functional devices conveniently in engineering application, a simplified parametric helical structure was proposed to replace actual irregular cochlea for bionic design, and based on the computational results of such a bionic parametric helical structure, it is suggested that the overall cochlear is a local resonant system with the negative dynamic effective mass characteristics. There are many potential applications in the bandboard energy recovery device, cochlear implant, and acoustic black hole.

  12. Computational Ocean Acoustics

    CERN Document Server

    Jensen, Finn B; Porter, Michael B; Schmidt, Henrik

    2011-01-01

    Since the mid-1970s, the computer has played an increasingly pivotal role in the field of ocean acoustics. Faster and less expensive than actual ocean experiments, and capable of accommodating the full complexity of the acoustic problem, numerical models are now standard research tools in ocean laboratories. The progress made in computational ocean acoustics over the last thirty years is summed up in this authoritative and innovatively illustrated new text. Written by some of the field's pioneers, all Fellows of the Acoustical Society of America, Computational Ocean Acoustics presents the latest numerical techniques for solving the wave equation in heterogeneous fluid–solid media. The authors discuss various computational schemes in detail, emphasizing the importance of theoretical foundations that lead directly to numerical implementations for real ocean environments. To further clarify the presentation, the fundamental propagation features of the techniques are illustrated in color. Computational Ocean A...

  13. ESR detection of free radicals produced in irradiated fresh fruits and dried foods

    Energy Technology Data Exchange (ETDEWEB)

    Bustos G, E. [CICATA, IPN, 07000 Mexico D.F. (Mexico); Gomes, V.; Garcia, F. [IQUNAM, 04500 Mexico D.F. (Mexico); Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico)

    2007-07-01

    Full text: Electron spin resonance (ESR) technique was used to measure the stability of free radicals produced by the irradiation treatment in mangoes and in four spices: black pepper, oregano, 'guajillo' chili and 'morron' chili. The ESR spectra for mangoes were scanned in three different parts from the seeds and were recorded in fresh and dried tissues. The ESR spectra in fresh tissue of no irradiated mangoes, were a sextet line signal produced by Mn{sup 2+} ion and a singlet centered at g = 2.00 produced by the endogenous radical. New resonances were observed in the irradiated samples at 1.5 mT and 3 mT respects to the center line for right and left side. These new resonance signals were-observed for eight days in mangoes treated at 1.00 kGy, and for three days at 0.15 kGy. The resonance due to the irradiation was observed in Iyophilized mangoes only one day after the treatment, in the vacuum dried samples, no new resonances were observed. The triplet signal, as well as the central single line appeared after irradiation in black pepper, morron chili and guajillo chili. These signals were also observed in the irradiated spices at any radiation dose higher than 1.0 kGy. The signals decrease promptly, in ten days after the 'irradiation. It was not possible to observe the triplet signal in oregano, even when the samples were analyzed immediately after irradiation treatment. The only signal observed in irradiated spice was the endogenous radical. This signal increased as the radiation dose increased and decreased during storage time at room temperature. Results showed that free radicals produced in irradiated fresh fruits or dried foods have a quick recombination. It was observed that in the spices the signal remains for several weeks meanwhile only eight days in mangoes. (Author)

  14. Estrogen Receptor Gene (ESR1 PVUII and XBAI Polymorphisms and Bone Mineral Density in Kazakh Women

    Directory of Open Access Journals (Sweden)

    Ainur Akilzhanova

    2014-01-01

    Full Text Available Introduction: Osteoporosis is a common age-related disease that is strongly influenced by genetics. Polymorphisms of the estrogen receptor gene alpha (ESR1 are consistently been associated with bone mineral density (BMD and fracture. The purpose of this investigation was to evaluate potential association of single nucleotide polymorphism (SNP variants of the ESR1 gene and bone mineral density (BMD of the lumbar spine in Kazakh women. Methods: 140 female participants in Pavlodar clinics with varying measures of BMD. We are examined the potential association of BMD with 2 SNPs from the ESR1 gene (rs2234693 [PvuII] and rs9340799 [XbaI]. Genotyping of the PvuII and XbaI polymorphisms was performed by direct sequencing of the gene fragments containing restriction sites with the identification of genotypes PP, Pp, pp and XX, Xx, xx respectively. Results: Unadjusted mean BMD values ranged from 1.14±0.14 g/cm2 in Caucasian women and 1.03±0.11 g/cm2 in Asian women. The association between PvuII polymorphism and BMD at the lumbar spine (p= 0.04 for PP=Pp=pp was statistically significant in all women. The XbaI polymorphism was not associated with BMD at lumbar spine. The relative risk for low BMD was higher for the marker PvuII (RR=1.51 than for the marker XbaI (RR=1.35. Conclusion: The PvuII polymorphism had a weak association with lumbar spine BMD.  XbaI polymorphism was unlikely to be a predictor of lumbar spine BMD in Kazakh women. These conclusions could help to determine the genetic risk factors for osteoporosis; however, further studies on the association between gene polymorphisms and BMD are needed including larger numbers of participants and genes to clarify genetic risks.

  15. Technical proposal of the 4π detector for SIS/ESR

    International Nuclear Information System (INIS)

    A 4π spectrometer for the detection of charged particles and photons produced in the SIS/ESR facility is proposed. It consists of a magnetic spectrometer with a central drift chamber, a two-arm photon spectrometer, an array of plastic scintillators, and a system consisting of silicon transmission detectors and gas-filled ionization chambers for the detection of nuclear fragments stopped in the scintillator modules. This system shall be able to measure correlations between photons and charged particles and to discriminate charged particles by tracking in the magnetic field. The data acquisition and processing systems are also described. (HSI)

  16. Comparison study of tooth enamel ESR spectra of cows, goats and humans.

    Science.gov (United States)

    Jiao, Ling; Liu, Zhong-Chao; Ding, Yan-Qiu; Ruan, Shu-Zhou; Wu, Quan; Fan, Sai-Jun; Zhang, Wen-Yi

    2014-11-01

    The ESR radiation dosimetric properties of tooth enamel samples from cows and goats were investigated and compared with those of human samples. Samples were prepared first mechanically, and then chemically. The study results showed that the native signals from cow and goat samples were weaker than those from human samples; the radiation sensitivities for cow and goat samples were very close to those of human tooth enamel samples. These results indicated that cow and goat teeth could be alternative materials for radiation dose estimation.

  17. The guanine cation radical: investigation of deprotonation states by ESR and DFT.

    Science.gov (United States)

    Adhikary, Amitava; Kumar, Anil; Becker, David; Sevilla, Michael D

    2006-11-30

    This work reports ESR studies that identify the favored site of deprotonation of the guanine cation radical (G*+) in an aqueous medium at 77 K. Using ESR and UV-visible spectroscopy, one-electron oxidized guanine is investigated in frozen aqueous D2O solutions of 2'-deoxyguanosine (dGuo) at low temperatures at various pHs at which the guanine cation radical, G*+ (pH 3-5), singly deprotonated species, G(-H)* (pH 7-9), and doubly deprotonated species, G(-2H)*- (pH > 11), are found. C-8-deuteration of dGuo to give 8-D-dGuo removes the major proton hyperfine coupling at C-8. This isolates the anisotropic nitrogen couplings for each of the three species and aids our analyses. These anisotropic nitrogen couplings were assigned to specific nitrogen sites by use of 15N-substituted derivatives at N1, N2, and N3 atoms in dGuo. Both ESR and UV-visible spectra are reported for each of the species: G*+, G(-H)*, and G(-2H)*-. The experimental anisotropic ESR hyperfine couplings are compared to those obtained from DFT calculations for the various tautomers of G(-H)*. Using the B3LYP/6-31G(d) method, the geometries and energies of G*+ and its singly deprotonated state in its two tautomeric forms, G(N1-H)* and G(N2-H)*, were investigated. In a nonhydrated state, G(N2-H)* is found to be more stable than G(N1-H)*, but on hydration with seven water molecules G(N1-H)* is found to be more stable than G(N2-H)*. The theoretically calculated hyperfine coupling constants (HFCCs) of G*+, G(N1-H)*, and G(-2H)*- match the experimentally observed HFCCs best on hydration with seven or more waters. For G(-2H)*-, the hyperfine coupling constant (HFCC) at the exocyclic nitrogen atom (N2) is especially sensitive to the number of hydrating water molecules; good agreement with experiment is not obtained until nine or 10 waters of hydration are included.

  18. Influence of Thermal Homogenization Treatment on Structure and Impact Toughness of H13 ESR Steel

    Institute of Scientific and Technical Information of China (English)

    MA Dang-shen; ZHOU Jian; CHEN Zai-zhi; ZHANG Zhong-kan; CHEN Qi-an; LI De-hui

    2009-01-01

    The as-cast microstrueture of H13 ESR ingot and the influence of high temperature diffusion treatment on the structure and impact toughness have been investigated. The results show that the dendrite arm spacing gradually becomes wide from the surface to the center of ingot, and the large primary carbide particles always exist in interdendritic segregation areas; by means of high temperature diffusion treatment of ingot prior to hot forging, the banded segregation is nearly eliminated, the annealed structure is more uniform and the isotropic properties have been improved remarkably.

  19. A study of the radiation chemistry of poly(chlorotrifluoroethylene) by ESR spectroscopy

    Science.gov (United States)

    Hill, David J. T.; Thurecht, Kristofer J.; Whittaker, Andrew K.

    2003-12-01

    The ESR spectra of poly(chlorotrifluoroethylene) were recorded following γ-radiolysis under vacuum at room temperature and 77 K. The very broad spectrum at 77 K revealed little fine structure with which to identity the radicals formed upon irradiation, but subsequent photobleaching and annealing studies, together with radiolytic studies at higher temperatures, afforded scope for making radical assignments. Both main-chain radicals and a range of chain-end radicals have been identified. The G-values for radical formation were 1.55, 0.36 and 0.32 at 77 K, 273 K and room temperature, respectively.

  20. ESR studies of some oxotetrahalo complexes of vanadium(IV) and molybdenum(V)

    International Nuclear Information System (INIS)

    ESR spectra of [VOF4]2- and [MoOF4]- have been studied in single crystals of (NH4)2SbF5 and spectra of [MoOCl4]- in single crystals of (NH4)2SbCl5. The spin-Hamiltonian parameters of these pentacoordinated complexes have been obtained and compared with those for the corresponding hexacoordinated species. Molecular orbital parameters for the penta- and hexacoordinated species obtained from experimental g- and A-tensor components have been compared with values calculated by the MS-SCF-Xα method

  1. Proceedings of the workshop on experiments and experimental facilities at SIS/ESR

    International Nuclear Information System (INIS)

    The present proceedings contain the abstracts of the proposals and letters of intent prepared by the authors for general distribution. The abstracts are organized according to the sessions in which they were presented at the workshop. The program of the workshop is also included as is the list of attendees. In addition we have included two recent descriptions of the accelerator facilities providing information on the latest status of the expected beam schedule for SIS and performance characteristics of the ESR. (orig./HSI)

  2. Quality assessment of coffee beans with ESR and gamma-ray irradiation

    International Nuclear Information System (INIS)

    Peroxy radical formation in raw coffee beans of different qualities and origins from all over the world has been studied with electron spin resonance (ESR) analysis. The γ-ray equivalent absorbed dose (ED) which creates the same concentration of radicals is obtained by the additive γ-ray irradiation of the coffee beans. The ED and the cup quality is somewhat inversely related suggesting that the peroxidation of the unsaturated fatty acid is somewhat indicative of the degree of the aromatic decomposition and rancidity. (author)

  3. SYSTEMATIC ERROR FROM Th/U RATION IN LUMINESCENCE AND ESR DATING

    Institute of Scientific and Technical Information of China (English)

    LiShenghua; Man-Yin; 等

    1995-01-01

    In luminescence and ESR dating methods,total count rate from thick source alpha counting is commonly used for estimating annual dose with assumption of equal activities for both uranium and thorium decay chains.This is equal to a Th/U weight ratio of 3.2. The systematic error in total dose rate due to uncertainty of the ratio is calculated.It is found that the error is insignificant for uniformly distributed samples such as sediment,but can be significant for some extreme circumstances.

  4. ESR of O3- trapped in γ-irradiated NaClO3

    International Nuclear Information System (INIS)

    The ESR spectra of γ-irradiated NaClO3 was analysed at Q-Band, between 110 to 300 K. The single crystals were annealed at 1800C until the spectra indicated the presence of only one paramagnetic center. This center was identified as the ozonide O3-. Four magnetically inequivalent sites per unit cell with symmetry axes along the cube diagonals were observed. The axial symmetry found for the g-tensor was interpreted in terms of molecule rotation around the trigonal axes. A rotational frequency of 2x109 c/s and an activation energy of 10 mev for the rotational motion could be estimated. (author)

  5. Flat acoustic lens by acoustic grating with curled slits

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Pai; Xiao, Bingmu; Wu, Ying, E-mail: ying.wu@kaust.edu.sa

    2014-10-03

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry–Perot resonance. - Highlights: • Expression of transmission coefficient of an acoustic grating with curled slits. • Non-dispersive and tunable effective medium parameters for the acoustic grating. • A flat acoustic focusing lens with gradient index by using the acoustic grating.

  6. Acoustic mapping velocimetry

    Science.gov (United States)

    Muste, M.; Baranya, S.; Tsubaki, R.; Kim, D.; Ho, H.; Tsai, H.; Law, D.

    2016-05-01

    Knowledge of sediment dynamics in rivers is of great importance for various practical purposes. Despite its high relevance in riverine environment processes, the monitoring of sediment rates remains a major and challenging task for both suspended and bed load estimation. While the measurement of suspended load is currently an active area of testing with nonintrusive technologies (optical and acoustic), bed load measurement does not mark a similar progress. This paper describes an innovative combination of measurement techniques and analysis protocols that establishes the proof-of-concept for a promising technique, labeled herein Acoustic Mapping Velocimetry (AMV). The technique estimates bed load rates in rivers developing bed forms using a nonintrusive measurements approach. The raw information for AMV is collected with acoustic multibeam technology that in turn provides maps of the bathymetry over longitudinal swaths. As long as the acoustic maps can be acquired relatively quickly and the repetition rate for the mapping is commensurate with the movement of the bed forms, successive acoustic maps capture the progression of the bed form movement. Two-dimensional velocity maps associated with the bed form migration are obtained by implementing algorithms typically used in particle image velocimetry to acoustic maps converted in gray-level images. Furthermore, use of the obtained acoustic and velocity maps in conjunction with analytical formulations (e.g., Exner equation) enables estimation of multidirectional bed load rates over the whole imaged area. This paper presents a validation study of the AMV technique using a set of laboratory experiments.

  7. Acoustic sniper localization system

    Science.gov (United States)

    Prado, Gervasio; Dhaliwal, Hardave; Martel, Philip O.

    1997-02-01

    Technologies for sniper localization have received increased attention in recent months as American forces have been deployed to various trouble spots around the world. Among the technologies considered for this task acoustics is a natural choice for various reasons. The acoustic signatures of gunshots are loud and distinctive, making them easy to detect even in high noise background environments. Acoustics provides a passive sensing technology with excellent range and non line of sight capabilities. Last but not least, an acoustic sniper location system can be built at a low cost with off the shelf components. Despite its many advantages, the performance of acoustic sensors can degrade under adverse propagation conditions. Localization accuracy, although good, is usually not accurate enough to pinpoint a sniper's location in some scenarios (for example which widow in a building or behind which tree in a grove). For these more demanding missions, the acoustic sensor can be used in conjunction with an infra red imaging system that detects the muzzle blast of the gun. The acoustic system can be used to cue the pointing system of the IR camera in the direction of the shot's source.

  8. From Architectural Acoustics to Acoustical Architecture Using Computer Simulation

    OpenAIRE

    Schmidt, Anne Marie Due; KIRKEGAARD, Poul Henning

    2005-01-01

    Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to inve...

  9. Underwater Applications of Acoustical Holography

    Directory of Open Access Journals (Sweden)

    P. C. Mehta

    1984-01-01

    Full Text Available The paper describes the basic technique of acoustical holography. Requirements for recording the acoustical hologram are discussed with its ability for underwater imaging in view. Some practical systems for short-range and medium-range imaging are described. The advantages of acoustical holography over optical imaging, acoustical imaging and sonars are outlined.

  10. Study on the Effect of ESR and FSH β Genes on Litter Size in Local Northeast Three Pig Breeds

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The method of PCR-RFLP was used to analyze the effects of ESR and FSH β genotypes on the litter size,especially the corresponding changes with the difference of genotype distributions in the Min,Sanjiang and Junmu I pigs.The results show that the ESR and FSH β genes are the major genes of litter size;the heterozygous genotype for ESR as well as for FSH β locus has a more litter size than others.However,the combined genotype ABDD means a more litter size than other genotypes,the frequencies of the heterozygous genotypes in Sanjiang and Junmu I are lower than in Min which maybe one of the most important reasons for the little litter sizes of those two breeds.

  11. ESR1 gene status correlates with estrogen receptor protein levels measured by ligand binding assay and immunohistochemistry

    DEFF Research Database (Denmark)

    Laenkholm, Anne-Vibeke; Knoop, Ann; Ejlertsen, Bent Laursen;

    2012-01-01

    level determined by two different methods and ESR1 gene copy number. From 289 primary high-risk breast cancer patients, randomized in the Danish Breast Cancer Cooperative Group (DBCG) 77C trial, results from cytosolic ER levels were available from ligand binding assays. Archival tumor tissue...... (ratio ESR1/CEN-6 from 1.30 to 1.99) in 19% of the patients. A positive correlation of ESR1 FISH with both ER-cytosol and ER IHC was found (p gene are associated with higher ER protein content measured by ligand binding assay and a more intense nuclear......The Estrogen Receptor (ER) is an established predictive marker for the selection of adjuvant endocrine treatment in early breast cancer. During the 1990s Immunohistochemistry (IHC) replaced cytosol based assays for determination of ER status. This study examined the association between ER protein...

  12. Photochemical synthesis of simple organic free radicals on simulated planetary surfaces - An ESR study

    Science.gov (United States)

    Tseng, S.-S.; Chang, S.

    1975-01-01

    Electron spin resonance (ESR) spectroscopy provided evidence for formation of hydroxyl radicals during ultraviolet photolysis (254 nm) at -170 C of H2O adsorbed on silica gel or of silica gel alone. The carboxyl radical was observed when CO or CO2 or a mixture of CO and CO2 adsorbed on silica gel at -170 C was irradiated. The ESR signals of these radicals slowly disappeared when the irradiated samples were warmed to room temperature. However, reirradiation of CO or CO2, or the mixture CO and CO2 on silica gel at room temperature then produced a new species, the carbon dioxide anion radical, which slowly decayed and was identical with that produced by direct photolysis of formic acid adsorbed on silica gel. The primary photochemical process may involve formation of hydrogen and hydroxyl radicals. Subsequent reactions of these radicals with adsorbed CO or CO2 or both yield carboxyl radicals, CO2H, the precursors of formic acid. These results confirm the formation of formic acid under simulated Martian conditions and provide a mechanistic basis for gauging the potential importance of gas-solid photochemistry for chemical evolution on other extraterrestrial bodies, on the primitive earth, and on dust grains in the interstellar medium.

  13. The radiation chemistry of ultem at 77 K as revealed by ESR spectroscopy

    International Nuclear Information System (INIS)

    Radical formation in ultem following γ-radiolysis has been reassessed, and the G(R*) values at different temperatures have been determined by ESR spectroscopy. The radical assignment and radical reactivity have been re-examined by photobleaching and thermal annealing studies. Photobleachable radical anions were found to comprise ∼40% of the total number of radicals formed on radiolysis at 77 K. Spectral subtraction methods, ESR spectral simulations, measurement of g-values and the hyperfine splitting constants were used to identify the other radical intermediates. The principal chain scission radicals are formed due to scission of the main-chain at (i) the ether linkage, (ii) the isopropylidene group and (iii) the imide ring in the main chain. The side chain methyl groups of the isopropylidine units also lose hydrogen to form methylene radicals. The five-line spectrum observed to decay in the temperature range 370-430 K, which has not been assigned previously, has been identified as being characteristic of a di-substituted benzyl radical

  14. The radiation chemistry of ultem at 77 K as revealed by ESR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Devasahayam, Sheila; Hill, David J.T. E-mail: hill@chemistry.uq.edu.au; Pomery, Peter J.; Whittaker, Andrew K

    2002-07-01

    Radical formation in ultem following {gamma}-radiolysis has been reassessed, and the G(R*) values at different temperatures have been determined by ESR spectroscopy. The radical assignment and radical reactivity have been re-examined by photobleaching and thermal annealing studies. Photobleachable radical anions were found to comprise {approx}40% of the total number of radicals formed on radiolysis at 77 K. Spectral subtraction methods, ESR spectral simulations, measurement of g-values and the hyperfine splitting constants were used to identify the other radical intermediates. The principal chain scission radicals are formed due to scission of the main-chain at (i) the ether linkage, (ii) the isopropylidene group and (iii) the imide ring in the main chain. The side chain methyl groups of the isopropylidine units also lose hydrogen to form methylene radicals. The five-line spectrum observed to decay in the temperature range 370-430 K, which has not been assigned previously, has been identified as being characteristic of a di-substituted benzyl radical.

  15. The radiation chemistry of ultem at 77 K as revealed by ESR spectroscopy

    Science.gov (United States)

    Devasahayam, Sheila; Hill, David J. T.; Pomery, Peter J.; Whittaker, Andrew K.

    2002-07-01

    Radical formation in ultem following γ-radiolysis has been reassessed, and the G( R*) values at different temperatures have been determined by ESR spectroscopy. The radical assignment and radical reactivity have been re-examined by photobleaching and thermal annealing studies. Photobleachable radical anions were found to comprise ≈40% of the total number of radicals formed on radiolysis at 77 K. Spectral subtraction methods, ESR spectral simulations, measurement of g-values and the hyperfine splitting constants were used to identify the other radical intermediates. The principal chain scission radicals are formed due to scission of the main-chain at (i) the ether linkage, (ii) the isopropylidene group and (iii) the imide ring in the main chain. The side chain methyl groups of the isopropylidine units also lose hydrogen to form methylene radicals. The five-line spectrum observed to decay in the temperature range 370-430 K, which has not been assigned previously, has been identified as being characteristic of a di-substituted benzyl radical.

  16. Synthesis of silver nanoparticles using DL-alanine for ESR dosimetry applications

    International Nuclear Information System (INIS)

    The potential use of alanine for the production of nanoparticles is presented here for the first time. Silver nanoparticles were synthesized using a simple green method, namely the thermal treatment of silver nitrate aqueous solutions with DL-alanine. The latter compound was employed both as a reducing and a capping agent. Particles with average size equal to 7.5 nm, face-centered cubic crystalline structure, narrow size distribution, and spherical shape were obtained. Interaction between the silver ions present on the surface of the nanoparticles and the amine group of the DL-alanine molecule seems to be responsible for reduction of the silver ions and for the stability of the colloid. The bio-hybrid nano-composite was used as an ESR dosimeter. The amount of silver nanoparticles in the nanocomposite was not sufficient to cause considerable loss of tissue equivalency. Moreover, the samples containing nanoparticles presented increased sensitivity and reduced energetic dependence as compared with pure DL-alanine, contributing to the construction of small-sized dosimeters. - Highlights: ► The synthesis is environmentally benign, easy to perform, and of low-cost. ► DL-Alanine was employed both as reducing and capping agent. ► Mean size of 7.5 nm, narrow size distribution, and spherical shape of particles. ► Increased sensitivity and reduced energetic dependence compared with pure alanine. ► The nanocomposite has potential application for ESR dosimetry.

  17. Use of ESR and HPLC to follow the anaerobic reaction catalysed by lipoxygenases.

    Science.gov (United States)

    Brandicourt, Stéphanie; Nicolas, Jacques; Boussard, Aline; Riquet, Anne-Marie

    2015-02-01

    The measurement of the 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL) consumption by using ESR allows to follow the anaerobic reaction between linoleic acid (LH) and its 13-hydroperoxide (LOOH) catalysed by lipoxygenase. During this reaction, two types of radicals are initially obtained, alkyl (L) and alkoxyl (LO) radicals which formed two types of adducts (LT and OLT) with TEMPOL as characterised by HPLC. The stoichiometry of the adduct formation is two mole of TEMPOL consumed for one mole of LH and one mole of LOOH. Using ESR, the kinetic parameters and the mechanism of the anaerobic reaction have been determined at pH 6.5 for three different lipoxygenases, soybean, horse bean and wheat and compared to the values obtained at pH 9 for soybean lipoxygenase. Wheat lipoxygenase is very weakly active compared to the other enzymes. An uncompetitive inhibition of the anaerobic reaction catalysed by soybean and horse bean lipoxygenases was observed with 2,6-di-tert-butyl-4-methylphenol (BHT). PMID:25172715

  18. Active and passive smoking, IL6, ESR1, and breast cancer risk

    Science.gov (United States)

    Curtin, Karen; Giuliano, Anna R.; Sweeney, Carol; Baumgartner, Richard; Edwards, Sandra; Wolff, Roger K.; Baumgartner, Kathy B.; Byers, Tim

    2008-01-01

    We evaluated the association between smoking and risk of breast cancer in non-Hispanic white (NHW) and Hispanic or American Indian (HAI) women living in the Southwestern United States. Data on lifetime exposure to active and passive smoke data were available from 1527 NHW cases and 1601 NHW controls; 798 HAI cases and 924 HAI controls. Interleukin 6 (IL6) and Estrogen Receptor alpha (ESR1) polymorphisms were assessed in conjunction with smoking. Pack-years of smoking (≥15) were associated with increased risk of pre-menopausal breast cancer among NHW women (OR 1.6, 95% CI 1.1–2. 4). Passive smoke increased risk of pre-menopausal breast cancer for HAI women (OR 1.9, 95% CI 1.1–3.1 everyone; OR 2.3, 95% CI 1.2–4.5 nonsmokers). HAI pre-menopausal women who were exposed to 10+ h of passive smoke per week and had the rs2069832 IL6 GG genotype had over a fourfold increased risk of breast cancer (OR 4.4, 95% CI 1.5–12.8; P for interaction 0.01). Those with the ESR1 Xba1 AA genotype had a threefold increased risk of breast cancer if they smoked ≥15 pack-years relative to non-smokers (P interaction 0.01). These data suggest that breast cancer risk is associated with active and passive smoking. PMID:17594514

  19. TL, OSL and ESR properties of nanostructured KAlSi3O8:Mn Glass

    International Nuclear Information System (INIS)

    Glass samples of KAlSi3O8:Mn were synthesized by sol-gel technique and the incorporation effects of Mn on the TL, OSL and ESR signals were studied. Its morphologies were analyzed through Transmission Electron Microscopy (TEM), Energy Dispersive Spectroscopy (EDS). Samples were obtained with five different molar concentrations of 0.25, 0.5, 1, 2 and 5 mol% of Mn. TEM micrographs indicated the occurrence of nanoparticles of Mn2SiO4 with 200 nm of size approximately. Results of TL spectra showed a broad emission band from 450 to 700 nm with a peak at 575 nm approximately, and fitting very well with the characteristic lines of the Mn2+ emission features. The OSL decay can be fitted by a sum of two exponentials. A proportional dose response curves of the OSL and TL for samples irradiated with γ-rays were verified. ESR results supplied six lines related to Mn2+ ions are observed superposed by a large isotropic line; the Hamiltonian components of these lines determined through simulation are I = 5/2, s = 5/2, g = 2.0060, A = 8.3 mT and s = 1/2, g = 2.0007 for the Mn2+ and isotropic lines.

  20. ESR detection of free radicals in gamma irradiated spices and other foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    Pilbrow, J.R.; Troup, G.J.; Hutton, D.R. [Monash Univ., Clayton, VIC (Australia). Dept. of Physics; Hunter, C.R. [Monash Univ., Clayton, VIC (Australia). Dept. of Astronomy

    1996-12-31

    Irradiation of various food products, including vegetables, fruits, meats, seafoods, herbs, spices and seeds by appropriate doses of {gamma}-rays has for many years been suggested as a means of killing or sterilizing bacteria, viruses and pests and, therefore, as a means of preserving the foods. The position of food irradiation has been under review in Australia generally, through consumer organisations and by a Federal Government (House of Representatives) inquiry. From these reviews and inquiries, recommendations for irradiation, packaging, and labelling etc., are emerging with, for example, an NH and MRC recommended maximum dose of 10 kGy for Australia, with 6 kGy being a minimum dose for grains and spices. In early studies, electron spin resonance (ESR) spectroscopy was used to detect stable free radicals in bone and cuticle and it was demonstrated that {gamma}-irradiation breaks down proteins and DNA. Earlier studies suggested that induced free radical signals in spices rapidly decayed to negligible levels after three weeks, especially if some moisture was present. Although the members of the Monash group do not carry out research formally in the area of food technology, participation in the ADMIT program was appropriate given the availability of suitable ESR and {sup 137}Cs irradiation facilities and interest both politically and amongst consumer groups regarding food irradiation. (author).

  1. Influence of the Mg-content on ESR-signals in synthetic calcium carbonate

    Energy Technology Data Exchange (ETDEWEB)

    Barabas, M.; Bach, A.; Mudelsee, M.; Mangini, A. (Akademie der Wissenschaften, Heidelberg (Germany, F.R.))

    1989-01-01

    Carbonate crystals doped with various concentrations of Mg{sup 2+}-ions have been grown by a gel-diffusion method. An increase of the Mg/Ca-ratio to more than about 1 caused a phase change in the crystal lattice from calcite to aragonite. The properties of the ESR-signals of the synthetic carbonates were studied and compared with natural marine carbonates. The following results were derived: (a) In the presence of Mg{sup 2+}-ions the synthetic carbonates display the same ESR-signals as natural calcites of marine origin with similar properties (thermal stability, radiation sensitivity). (b) The saturation value of the signal at g=2.0006 in synthetic calcites was found to be strongly related with the Mg-content in the crystals. (c) The signal at g=2.0036 (axial symmetry) which is present in calcite was not influenced by the Mg-concentration. Its saturation value decreases when the crystal phase changed from calcite to aragonite and in complement the signal at g=2.0031 appeared. (d) The signals at g=2.0057 and g=2.0031 are most probably not of organic origin. (author).

  2. Temperature experiments on mollusc samples: an approach to ESR signal identification

    Energy Technology Data Exchange (ETDEWEB)

    Katzenberger, O. (Koeln Univ. (Germany, F.R.). Geologisches Inst.); Debuyst, R.; De Canniere, P.; Dejehet, F.; Apers, D. (Louvain Univ., Louvain-la-Neuve (Belgium). Lab. de Chimie Inorganique et Nucleaire); Barabas, M. (Heidelberg Univ. (Germany, F.R.). Inst. fuer Umweltphysik)

    1989-01-01

    Powered mollusc samples, which were irradiated with {gamma} rays at room temperature, were analysed by ESR spectrometry at different temperatures ranging from 293 to {approx} 100 K. Gamma-ray irradiations, sometimes preceded by a thermal treatment at 180{sup 0}C, were also performed at 77 K and at 140-180{sup 0}C. From these experiments and from a study on non-powdered samples, it is concluded that the mollusc ESR spectrum is principally due to five paramagnetic species with the following values: (1) g = 2.0057; (2) g{sub parallel}=2.0033 and g{sub perpendicular}=2.0031 (the narrow g=2.0032 line); (3) gparallel=2.0017 and g{sub perpendicular}=2.0020 (the g=2.0019 line); (4) g=2.0007; (5) g{sub 1}=2.0032, g{sub 2}=2.0016 and g{sub 3}=1.9973 (CO{sub 2}{sup -}). (author).

  3. E-layer dominated ionosphere observed by EISCAT/ESR radars during solar minimum

    Science.gov (United States)

    Cai, Hongtao; Li, Fei; Shen, Ge; Zhan, Weijia; Zhou, Kangjun; McCrea, Ian W.; Ma, Shuying

    2014-05-01

    E-layer dominated ionosphere (ELDI) is referred to vertical profiles having peak density at E-layer altitudes (Mayer and Jakowski, 2009). In this paper, characteristics of ELDI were investigated with the help of field-aligned measurements of EISCAT/ESR radars during 2009-2011. ELDI events were identified with simple but reasonable criterions, in which a minimal duration was required to exclude possible 'fake' events induced by random errors in measurements. It was found that ELDI were observed more often in winter than other seasons. In winter, occurrence of ELDI peaks around mid-night at auroral latitude, while it reaches its maximum around geomagnetic local noon at ESR latitude. Our results imply that ELDI looks like a sporadic rather than a regular phenomenon, being contrary to previous results inferred from radio occultation measurements. Discrepancy in duration of ELDI events observed by the two radars is remarkable, being 30 minutes at TromsØ on average and about a half of it at Svalbard. During the presence of ELDI, average thickness of E-layer exhibits undetectable variations at the two sites, as well as HmE and the ratio of NmE/NmF. Case studies reveal that either extra E-layer ionization possible induced by auroral precipitation or density depletion in F-layer caused by plasma convection alone could lead to the presence of ELDI. We suggest that both them play an important role in ELDI formation.

  4. Improvement of ESR dosimetry for thermal neutron beams through the addition of gadolinium

    Energy Technology Data Exchange (ETDEWEB)

    Brai, M [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Marrale, M [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Gennaro, G [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Bartolotta, A [Dipartimento Farmacochimico, Tossicologico e Biologico, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); D' Oca, M C [Dipartimento Farmacochimico, Tossicologico e Biologico, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); Rosi, G [Centro di Ricerche ENEA, Casaccia, Rome (Italy)

    2007-09-07

    In this paper, the addition of gadolinium is proposed as a useful tool to enhance the electron spin resonance (ESR) sensitivity of organic compounds to thermal neutrons. The target of this work is the detection, through the ESR technique, of the thermal neutron fluence in a mixed field of photons and neutrons. Gadolinium was chosen because it has a very high capture cross section to thermal neutrons; its nuclear reaction with thermal neutrons induces complex inner shell transitions that generate, besides other particles, Auger electrons, which in turn release their energy in the neighborhood (only several nanometers) of the place of reaction. Gadolinium was added to two organic molecules: alanine and ammonium tartrate. The main result obtained was a greater neutron sensitivity for dosimeters with gadolinium than for those without gadolinium for both organic molecules used. Since a dosimeter pair is required to discriminate between the two components of a mixed field, we studied the response of each dosimeter pair irradiated in a mixed field. Through a blind test we verified the usefulness of this dosimetric system and we obtained an estimate of the fluence in the mixed field with a relative uncertainty of 3%, when the pair composed of an alanine dosimeter and a dosimeter with alanine and gadolinium is used.

  5. Radiolysis of carbohydrates as studied by ESR and spin-trapping

    International Nuclear Information System (INIS)

    Studies concerning the radicals produced in glycerol by reactions with OH radicals have been carried out by investigating deuterated glycerol (glycerol-d8) by spin-trapping with 2-methyl-2-nitrosopropane. Free radicals produced in linear carbohydrates such as xylitol, dulcitol, D-sorbitol and D-mannitol by reactions with OH radicals as well as by direct γ-radiolysis have been also investigated by spin-trapping. The ESR spectra of the spin-trapped radicals were analysed on the basis of the results from ESR and spin-trapping experiments on glycerol and deuterated glycerol, and the formation of three radical species, CHO-CH-, CH2-CO-and HO-CH-, due to both OH reactions and direct γ-radiolysis was confirmed for all compounds. The presence of a radical, -CO-CH-, was detected for xylitol, D-sorbitol and D-mannitol. General reaction processes induced by OH reactions or γ-radiolysis in the solid state are discussed. (author)

  6. Identification of. gamma. -irradiated spices by electron spin resonance (ESR) spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Uchiyama, Sadao; Kawamura, Yoko; Saito, Yukio (National Inst. of Hygienic Sciences, Tokyo (Japan))

    1990-12-01

    The electron spin resonance (ESR) spectrometry spectra of white (WP), black (BP) and red (Capsicum annuum L. var. frutescerns L., RP) peppers each had a principal signal with a g-value of 2.0043, and the intensities of the principal signals were increased not only by {gamma}-irradiation but also by heating. Irradiated RP also showed a minor signal -30G from the principal one, and the intensity of the minor signal increased linearly with increasing dose from 10 to 50 kGy. Since the minor signal was observed in RP irradiated at 10 kGy and stored for one year, but did not appear either after heating or after exposure to this signal is unique to {gamma}-irradiated RP and should therefore be useful for the identification of {gamma}-irradiated spices of Capsicum genus, such as paprika and chili pepper. The computer simulation of the ESR spectra suggested that the minor signal should be assigned to methyl radical and the principal signal mainly to a combination of phenoxyl and peroxyl radicals. Such minor signals were found in {gamma}-irradiated allspice and cinnamon among 10 kinds of other spices. (author).

  7. ESR of trapped centers in γ irradiated silver chlorates single crystals

    International Nuclear Information System (INIS)

    The paramagnetic centers O-3, ClO2, and (ClO2--Cl)- have been identified in irradiated AgClO3 single crystals by X and Q band ESR experiments at room temperatures and by the optical absorption bands at 480 and 360 nm, characteristic of the first two centers, respectively. The ESR spectrum and its angular dependence show that the first two centers have two magnetically inequivalent sites per unit cell. The third center was clearly observed only at certain orientations. The data for ClO2 show that the principal directions of the g and A tensors do not coincide; the two magnetically inequivalent sites have similar principal values of the g and A tensors related by a 900 rotation about the tetragonal crystal axis of symmetry, and can therefore be assumed to be chemically equivalent. It is found that the ClO2 center is formed substitutionally in the ClO-3 ion position, but that the ozonide O-3 is not. The thermal annealing of the γ irradiated AgClO3 has revealed an increase in the concentration of the O-3 radical that seems to be connected with the simultaneous destruction of the ClO2 center

  8. Radiation induced radical in barium sulphate for ESR dosimetry: a preliminary study

    International Nuclear Information System (INIS)

    Barium sulphate (BaSO4) was irradiated by γ-rays and analyzed with electron spin resonance (ESR) to study radiation induced radicals for materials as radiation dosimeter. The ESR spectrum for the radical species is characterized by a hole-type center with g factor of 2.019, 2.0127 and 2.0103 and electron-type center with g factor of 2.0039, 2.0025 and 2.0001. The dosimetric signal with splitting factors of g=2.0039 is ascribed to SO3- radicals and 5G linewidth. The response to γ-ray dose ranging from 5 to 103 Gy, energy dependence calculation and the thermal stability have been studied. The number of free radicals per 100 eV (G-value) was obtained to be 0.25 ± 0.06 and 0.9 ± 0.18 for BaSO4 and alanine, respectively. The lifetime of radicals and the activation energy were estimated from Arrhenius plots to be approximately 325 ± 60 days, and 0.50 ± 0.09 eV respectively

  9. Problems associated with reworked teeth in electron spin resonance (ESR) dating

    Science.gov (United States)

    Blackwell, Bonnie A.

    A single radiation-sensitive ESR signal at g = 2.0018 occurs in well crystallized fossil tooth enamel, but not in modern teeth. In dating fossil teeth, the equivalent radiation dose (A Σ needed to produce the observed ESR signal is the integral, with respect to time, of the natural, environmental dose rate experienced by the tooth after its deposition. Regardless of the uranium (U) uptake history assumed, a reliable age estimate requires a good estimate for the external dose rate during the tooth's history. If teeth in a stratigraphic unit have been reworked from older units or are post-depositional intrusions, external dose rates measured in situ do not accurately reflect those experienced by the tooth. For teeth from a single unit, significant variations in the calculated ages, A Σs, enamel or dentine U concentrations all indicate mixed sample collections. Where enough subsamples can be collected from single teeth, isochron analyses negate the need for a separate external dose measurement, while calculating the sample age and the external dose rate experienced by the tooth. Failing that, modelling the sedimentary dose rates using time-averaged total external dose calculations becomes necessary. These principles are illustrated using teeth from the australopithecine sites Sterkfontein and Swartkrans, South Africa.

  10. Association of ESR1 gene tagging SNPs with breast cancer risk

    Science.gov (United States)

    Dunning, Alison M.; Healey, Catherine S.; Baynes, Caroline; Maia, Ana-Teresa; Scollen, Serena; Vega, Ana; Rodríguez, Raquel; Barbosa-Morais, Nuno L.; Ponder, Bruce A.J.; Low, Yen-Ling; Bingham, Sheila; Haiman, Christopher A.; Le Marchand, Loic; Broeks, Annegien; Schmidt, Marjanka K.; Hopper, John; Southey, Melissa; Beckmann, Matthias W.; Fasching, Peter A.; Peto, Julian; Johnson, Nichola; Bojesen, Stig E.; Nordestgaard, Børge; Milne, Roger L.; Benitez, Javier; Hamann, Ute; Ko, Yon; Schmutzler, Rita K.; Burwinkel, Barbara; Schürmann, Peter; Dörk, Thilo; Heikkinen, Tuomas; Nevanlinna, Heli; Lindblom, Annika; Margolin, Sara; Mannermaa, Arto; Kosma, Veli-Matti; Chen, Xiaoqing; Spurdle, Amanda; Change-Claude, Jenny; Flesch-Janys, Dieter; Couch, Fergus J.; Olson, Janet E.; Severi, Gianluca; Baglietto, Laura; Børresen-Dale, Anne-Lise; Kristensen, Vessela; Hunter, David J.; Hankinson, Susan E.; Devilee, Peter; Vreeswijk, Maaike; Lissowska, Jolanta; Brinton, Louise; Liu, Jianjun; Hall, Per; Kang, Daehee; Yoo, Keun-Young; Shen, Chen-Yang; Yu, Jyh-Cherng; Anton-Culver, Hoda; Ziogoas, Argyrios; Sigurdson, Alice; Struewing, Jeff; Easton, Douglas F.; Garcia-Closas, Montserrat; Humphreys, Manjeet K.; Morrison, Jonathan; Pharoah, Paul D.P.; Pooley, Karen A.; Chenevix-Trench, Georgia

    2009-01-01

    We have conducted a three-stage, comprehensive single nucleotide polymorphism (SNP)-tagging association study of ESR1 gene variants (SNPs) in more than 55 000 breast cancer cases and controls from studies within the Breast Cancer Association Consortium (BCAC). No large risks or highly significant associations were revealed. SNP rs3020314, tagging a region of ESR1 intron 4, is associated with an increase in breast cancer susceptibility with a dominant mode of action in European populations. Carriers of the c-allele have an odds ratio (OR) of 1.05 [95% Confidence Intervals (CI) 1.02–1.09] relative to t-allele homozygotes, P = 0.004. There is significant heterogeneity between studies, P = 0.002. The increased risk appears largely confined to oestrogen receptor-positive tumour risk. The region tagged by SNP rs3020314 contains sequence that is more highly conserved across mammalian species than the rest of intron 4, and it may subtly alter the ratio of two mRNA splice forms. PMID:19126777

  11. ESR of dislocation defects in MgF2 crystals--with more than 130 line peaks

    Institute of Scientific and Technical Information of China (English)

    Hou Bi-Hui; Zheng Ying-Guang; Shao Meng; Liu Feng-Yan; Fan Zhi-Da

    2005-01-01

    In this work, more than 130 line peaks in electron spin resonance (ESR) spectra have been discovered of the laser material MgF2 crystal in room-temperature experiments. A sample is cut from the shoulder part of the MgF2 crystal,and another is from the MgF2:Co crystal. The samples were not treated by any irradiation. The same anisotropic ESR spectra of the two samples indicate that the dopant Co2+ introduces defects which induce the same multinuclear free radicals as in dislocations in the sample of MgF2. These paramagnetic solid multinuclear free radicals show good stability, and their ESR spectra are found to be anisotropic. ESR signals are derived from three different types of multinuclear free radicals from a tentative simulation analysis.When the direction of the applied magnetic field is along the [100] or [010] orientation of the crystal, the magnetic field at which the ESR signals are detected ranges from 0.2294T to 0.4654T and the width of this range is 0.2362T (corresponding to an energy band of 0.233eV); the most narrow peak in the ESR spectra has a width △H about 1.28 × 10-3T.This width △H, equivalent to the energy difference of two neighbouring levels, is very small, only 1.85× 10-7eV (or 1.46 × 10-3cm- 1 ).This fact indicates that the ground state is highly degenerate, and splits into nearly quasi-continuous energy levels like an energy band in an applied magnetic field. It may be served as a new starting point of solid laser exciter frequency modulation.

  12. ESR of dislocation defects in MgF2 crystals—with more than 130 line peaks

    Science.gov (United States)

    Hou, Bi-Hui; Zheng, Ying-Guang; Shao, Meng; Liu, Feng-Yan; Fan, Zhi-Da

    2005-07-01

    In this work, more than 130 line peaks in electron spin resonance (ESR) spectra have been discovered of the laser material MgF2 crystal in room-temperature experiments. A sample is cut from the shoulder part of the MgF2 crystal and another is from the MgF2:Co crystal. The samples were not treated by any irradiation. The same anisotropic ESR spectra of the two samples indicate that the dopant Co2+ introduces defects which induce the same multinuclear free radicals as in dislocations in the sample of MgF2. These paramagnetic solid multinuclear free radicals show good stability and their ESR spectra are found to be anisotropic. ESR signals are derived from three different types of multinuclear free radicals from a tentative simulation analysis. When the direction of the applied magnetic field is along the [100] or [010] orientation of the crystal, the magnetic field at which the ESR signals are detected ranges from 0.2294T to 0.4654T and the width of this range is 0.2362T (corresponding to an energy band of 0.233eV); the most narrow peak in the ESR spectra has a width ΔH about 1.28×10-3T. This width ΔH, equivalent to the energy difference of two neighbouring levels, is very small, only 1.85×10-7eV (or 1.46×10-3cm-1). This fact indicates that the ground state is highly degenerate and splits into nearly quasi-continuous energy levels like an energy band in an applied magnetic field. It may be served as a new starting point of solid laser exciter frequency modulation.

  13. ESR1 Gene Polymorphisms and Prostate Cancer Risk: A HuGE Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Yu-Mei Wang

    Full Text Available Many published data on the association between single nucleotide polymorphisms (SNPs in the ESR1 gene and prostate cancer susceptibility are inconclusive. The aim of this Human Genome Epidemiology (HuGE review and meta-analysis is to derive a more precise estimation of this relationship.A literature search of PubMed, Embase, Web of Science and Chinese Biomedical (CBM databases was conducted from their inception through July 1st, 2012. Crude odds ratios (ORs with 95% confidence intervals (CIs were calculated to assess the strength of association.Twelve case-control studies were included with a total 2,165 prostate cancer cases and 3,361 healthy controls. When all the eligible studies were pooled into the meta-analysis, ESR1 PvuII (C>T and XbaI (A>G polymorphisms showed no association with the risk of prostate cancer. However, in the stratified analyses based on ethnicity and country, the results indicated that ESR1 PvuII (C>T polymorphism was significantly associated with increased risk of prostate cancer among Asian populations, especially among Indian population; while ESR1 XbaI (A>G polymorphism may significantly increase the risk of prostate cancer among American population. Furthermore, we also performed a pooled analysis for all eligible case-control studies to explore the role of codon 10 (T>C, codon 325 (C>G, codon 594 (G>A and +261G>C polymorphisms in prostate cancer risk. Nevertheless, no significant associations between these polymorphisms and the risk of prostate cancer were observed.Results from the current meta-analysis indicate that ESR1 PvuII (C>T polymorphism may be a risk factor for prostate cancer among Asian populations, especially among Indian population; while ESR1 XbaI (A>G polymorphism may increase the risk of prostate cancer among American population.

  14. Ocean acoustic reverberation tomography.

    Science.gov (United States)

    Dunn, Robert A

    2015-12-01

    Seismic wide-angle imaging using ship-towed acoustic sources and networks of ocean bottom seismographs is a common technique for exploring earth structure beneath the oceans. In these studies, the recorded data are dominated by acoustic waves propagating as reverberations in the water column. For surveys with a small receiver spacing (e.g., tomography, is developed that uses the travel times of direct and reflected waves to image ocean acoustic structure. Reverberation tomography offers an alternative approach for determining the structure of the oceans and advancing the understanding of ocean heat content and mixing processes. The technique has the potential for revealing small-scale ocean thermal structure over the entire vertical height of the water column and along long survey profiles or across three-dimensional volumes of the ocean. For realistic experimental geometries and data noise levels, the method can produce images of ocean sound speed on a smaller scale than traditional acoustic tomography. PMID:26723303

  15. Acoustic integrated extinction

    CERN Document Server

    Norris, Andrew N

    2015-01-01

    The integrated extinction (IE) is defined as the integral of the scattering cross-section as a function of wavelength. Sohl et al. [1] derived an IE expression for acoustic scattering that is causal, i.e. the scattered wavefront in the forward direction arrives later than the incident plane wave in the background medium. The IE formula was based on electromagnetic results, for which scattering is causal by default. Here we derive a formula for the acoustic IE that is valid for causal and non-causal scattering. The general result is expressed as an integral of the time dependent forward scattering function. The IE reduces to a finite integral for scatterers with zero long-wavelength monopole and dipole amplitudes. Implications for acoustic cloaking are discussed and a new metric is proposed for broadband acoustic transparency.

  16. Autonomous Acoustic Receiver System

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Collects underwater acoustic data and oceanographic data. Data are recorded onboard an ocean buoy and can be telemetered to a remote ship or shore station...

  17. Thermal Acoustic Fatigue Apparatus

    Data.gov (United States)

    Federal Laboratory Consortium — The Thermal Acoustic Fatigue Apparatus (TAFA) is a progressive wave tube test facility that is used to test structures for dynamic response and sonic fatigue due to...

  18. Acoustic Igniter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An acoustic igniter eliminates the need to use electrical energy to drive spark systems to initiate combustion in liquid-propellant rockets. It does not involve the...

  19. Acoustic Neuroma Educational Video

    Medline Plus

    Full Text Available ... treatment Summary Types Of Post-treatment Issues Resources Medical Resources Considerations When Selecting a Healthcare Professional Healthcare ... ANA? Mission Statement Board of Directors ANA Staff Medical Advisory Board News ANA Annual Reports Acoustic Neuroma ...

  20. Acoustics lecturing in Mexico

    Science.gov (United States)

    Beristain, Sergio

    2002-11-01

    Some thirty years ago acoustics lecturing started in Mexico at the National Polytechnic Institute in Mexico City, as part of the Bachelor of Science degree in Communications and Electronics Engineering curricula, including the widest program on this field in the whole country. This program has been producing acoustics specialists ever since. Nowadays many universities and superior education institutions around the country are teaching students at the B.Sc. level and postgraduate level many topics related to acoustics, such as Architectural Acoustics, Seismology, Mechanical Vibrations, Noise Control, Audio, Audiology, Music, etc. Also many institutions have started research programs in related fields, with participation of medical doctors, psychologists, musicians, engineers, etc. Details will be given on particular topics and development.

  1. An acoustic invisible gateway

    CERN Document Server

    Zhu, Yi-Fan; Liang, Bin; Kan, Wei-Wei; Yang, Jun; Cheng, Jian-Chun

    2015-01-01

    The recently-emerged concept of "invisible gateway" with the extraordinary capability to block the waves but allow the passage of other entities has attracted great attentions due to the general interests in illusion devices. However, the possibility to realize such a fascinating phenomenon for acoustic waves has not yet been explored, which should be of paramount significance for acoustical applications but would necessarily involve experimental difficulty. Here we design and experimentally demonstrate an acoustic invisible gateway (AIG) capable of concealing a channel under the detection of sound. Instead of "restoring" a whole block of background medium by using transformation acoustics that inevitably requires complementary or restoring media with extreme parameters, we propose an inherently distinct methodology that only aims at engineering the surface impedance at the "gate" to mimic a rigid "wall" and can be conveniently implemented by decorating meta-structures behind the channel. Such a simple yet ef...

  2. Principles of musical acoustics

    CERN Document Server

    Hartmann, William M

    2013-01-01

    Principles of Musical Acoustics focuses on the basic principles in the science and technology of music. Musical examples and specific musical instruments demonstrate the principles. The book begins with a study of vibrations and waves, in that order. These topics constitute the basic physical properties of sound, one of two pillars supporting the science of musical acoustics. The second pillar is the human element, the physiological and psychological aspects of acoustical science. The perceptual topics include loudness, pitch, tone color, and localization of sound. With these two pillars in place, it is possible to go in a variety of directions. The book treats in turn, the topics of room acoustics, audio both analog and digital, broadcasting, and speech. It ends with chapters on the traditional musical instruments, organized by family. The mathematical level of this book assumes that the reader is familiar with elementary algebra. Trigonometric functions, logarithms and powers also appear in the book, but co...

  3. Anal acoustic reflectometry

    DEFF Research Database (Denmark)

    Mitchell, Peter J; Klarskov, Niels; Telford, Karen J;

    2011-01-01

    Anal acoustic reflectometry is a new technique of assessing anal sphincter function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, the opening and closing elastance, and hysteresis.......Anal acoustic reflectometry is a new technique of assessing anal sphincter function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, the opening and closing elastance, and hysteresis....

  4. Acoustic surface cavitation

    OpenAIRE

    Zijlstra, Aaldert Geert

    2011-01-01

    Merely the presence of compressible entities, known as bubbles, greatly enriches the physical phenomena encountered when introducing ultrasound in a liquid. Mediated by the response of these bubbles, the otherwise diffuse and relatively low energy density of the acoustic field can induce strong, localized liquid motion, high internal temperatures and pressures as well as secondary acoustic emissions. In turn, these effects give rise to considerable stresses exerted on nearby objects and molec...

  5. Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface.

    Science.gov (United States)

    Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A

    2014-01-01

    Metasurfaces are a family of novel wavefront-shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality to their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a design and realization of an acoustic metasurface based on tapered labyrinthine metamaterials. The demonstrated metasurface can not only steer an acoustic beam as expected from the generalized Snell's law, but also exhibits various unique properties such as conversion from propagating wave to surface mode, extraordinary beam-steering and apparent negative refraction through higher-order diffraction. Such designer acoustic metasurfaces provide a new design methodology for acoustic signal modulation devices and may be useful for applications such as acoustic imaging, beam steering, ultrasound lens design and acoustic surface wave-based applications. PMID:25418084

  6. ESR Characterization and Activity of V2O5/γ-Al2O3 Catalysts for Dehydrogenation of Isobutane

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The ESR spectra of catalyst V2O5/γ-Al2O3 and its activity for the dehydrogenation of isobutane were investigated. On the basis of the results of the ESR spectroscopy associated with the TPR results, it is suggested that there is a strong interaction between V2O5 and γ-Al2O3 and the V4+ species on the surface is the active center of catalyst V2O5/γ-Al2O3 for this reaction.

  7. Acoustic vector sensor signal processing

    Institute of Scientific and Technical Information of China (English)

    SUN Guiqing; LI Qihu; ZHANG Bin

    2006-01-01

    Acoustic vector sensor simultaneously, colocately and directly measures orthogonal components of particle velocity as well as pressure at single point in acoustic field so that is possible to improve performance of traditional underwater acoustic measurement devices or detection systems and extends new ideas for solving practical underwater acoustic engineering problems. Although acoustic vector sensor history of appearing in underwater acoustic area is no long, but with huge and potential military demands, acoustic vector sensor has strong development trend in last decade, it is evolving into a one of important underwater acoustic technology. Under this background, we try to review recent progress in study on acoustic vector sensor signal processing, such as signal detection, DOA estimation, beamforming, and so on.

  8. Acoustic comfort in eating establishments

    DEFF Research Database (Denmark)

    Svensson, David; Jeong, Cheol-Ho; Brunskog, Jonas

    2014-01-01

    The subjective concept of acoustic comfort in eating establishments has been investigated in this study. The goal was to develop a predictive model for the acoustic comfort, by means of simple objective parameters, while also examining which other subjective acoustic parameters could help explain...... the feeling of acoustic comfort. Through several layers of anal ysis, acoustic comfort was found to be rather complex, and could not be explained entirely by common subjective parameters such as annoyance, intelligibility or privacy. A predictive model for the mean acoustic comfort for an eating establishment...

  9. Phononic crystals and acoustic metamaterials

    Directory of Open Access Journals (Sweden)

    Ming-Hui Lu

    2009-12-01

    Full Text Available Phononic crystals have been proposed about two decades ago and some important characteristics such as acoustic band structure and negative refraction have stimulated fundamental and practical studies in acoustic materials and devices since then. To carefully engineer a phononic crystal in an acoustic “atom” scale, acoustic metamaterials with their inherent deep subwavelength nature have triggered more exciting investigations on negative bulk modulus and/or negative mass density. Acoustic surface evanescent waves have also been recognized to play key roles to reach acoustic subwavelength imaging and enhanced transmission.

  10. Molecular cloning, characterization, tissue distribution and mRNA expression changes during the hibernation and reproductive periods of estrogen receptor alpha (ESR1) in Chinese alligator, Alligator sinensis.

    Science.gov (United States)

    Zhang, Ruidong; Hu, Yuehong; Wang, Huan; Yan, Peng; Zhou, Yongkang; Wu, Rong; Wu, Xiaobing

    2016-10-01

    Chinese alligator, Alligator sinensis, is a critically endangered reptile species unique to China. Little is known about the mechanism of growth- and reproduction-related hormones gene expression in Chinese alligator. Estrogens play important roles in regulating multiple reproduction- and non-reproduction-related functions by binding to their corresponding receptors. Here, the full-length cDNA of estrogen receptor alpha (ERα/ESR1) was cloned and sequenced from Chinese alligator for the first time, which comprises 1764bp nucleotides and encodes a predicted protein of 587 amino acids. Phylogenetic analysis of ESR1 showed that crocodilians and turtles were the sister-group of birds. The results of real-time quantitative PCR indicated that the ESR1 mRNA was widely expressed in the brain and peripheral tissues. In the brain and pituitary gland, ESR1 was most highly transcribed in the cerebellum. But in other peripheral tissues, ESR1 mRNA expression level was the highest in the ovary. Compared with hibernation period, ESR1 mRNA expression levels were increased significantly in the reproductive period (P0.05). The ESR1 mRNA expression levels changes during the two periods of different tissues suggested that ESR1 might play an important role in mediation of estrogenic multiple reproductive effects in Chinese alligator. Furthermore, it was the first time to quantify ESR1 mRNA level in the brain of crocodilians, and the distribution and expression of ESR1 mRNA in the midbrain, cerebellum and medulla oblongata was also reported for the first time in reptiles. PMID:27212643

  11. ESR and AMS-based 14C Dating of Mousterian Levels at Mujina Pećina, Dalmatia, Croatia

    NARCIS (Netherlands)

    Rink, W.J.; Karavanić, I.; Pettitt, P.B.; Plicht, J. van der; Smith, F.H.; Bartoll, J.; Karavanic, I.

    2002-01-01

    This paper presents the first chronometric dates for sediments that contain a Mousterian industry in Dalmatia (south Croatia). Electron spin resonance (ESR) dating was conducted on two teeth from the Mousterian level E1 at the site of Mujina Pećina. Additionally five bone and one charcoal sample fro

  12. Dating of the middle Palaeolithic site of Payre (Ardeche): new radiometric data (U-series and ESR methods)

    International Nuclear Information System (INIS)

    The site of Payre is located in Ardeche. Several archaeological layers containing lithic artefacts of Middle Palaeolithic were found. These artefacts lie associated with carbonate formations which are good chronostratigraphic markers. The U-series and ESR methods on bones and stalagmitic floors placed the human occupation between isotopic marine stages 7 and 4. (authors)

  13. Direct observation of hexamethylbenzenium radical cations generated during zeolite methanol-to-olefin catalysis: an ESR study.

    Science.gov (United States)

    Kim, Sun Jung; Jang, Hoi-Gu; Lee, Jun Kyu; Min, Hyung-Ki; Hong, Suk Bong; Seo, Gon

    2011-09-01

    The generation of hexamethylbenzenium radical cations as the key reaction intermediate in chabazite-type molecular sieve acids (i.e., H-SAPO-34 and H-SSZ-13) during the methanol-to-olefin process has been directly evidenced by ESR spectroscopy. PMID:21766115

  14. The use of ESR spectroscopy for the detection of irradiated mechanically recovered meat (MRM) in tertiary food products

    International Nuclear Information System (INIS)

    The use of electron spin resonance (ESR) spectroscopy as a detection method for irradiated food has been well documented in recent years, the research dealing mainly with primary products such as chicken, shellfish and fruit. An example of how the technique can be applied to processed food products was demonstrated when ESR spectroscopy was used to differentiate between samples of commercially irradiated and non-irradiated mechanically recovered turkey meat (MRM). The latter refers to meat which has been mechanically removed under high pressure from irregularly shaped bones subjected to hand-boning operations. The paste-like product contains small fragments of bone which can be extracted and used for the purposes of ESR spectroscopy provided a sufficient quantity is recovered. On a commercial scale MRM can be incorporated into other food, such as beef burgers, to produce a tertiary product. The aim of this experimental work, carried out simultaneously in Belfast and Strasbourg, was to compare two methods for extracting bone fragments from such tertiary products containing MRM at varying inclusion rates and to determine if ESR spectroscopy could be used to qualitatively detect the presence of small amounts of irradiated MRM. In addition, a number of coded foods containing either non-irradiated MRM were examined in order to establish the feasibility of applying the method to samples, the processing history of which was unknown. (author)

  15. ESR study on free radicals produced from hexane by vacuum-ultraviolet photolysis, sensitized photolysis, and γ-radiolysis

    International Nuclear Information System (INIS)

    The free radicals generated from polycrystalline hexane at 77K by photolysis with vacuum-ultraviolet light, sensitized photolysis, and γ-radiolysis were compared with each others using the ESR method. The selectivity of radical formation was found to depend on the excitation method. (author)

  16. Irradiation and ESR analysis temperature dependence of the gamma-ray response of alanine-polystyrene dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, T.; Morishita, N.; Itoh, H. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Biramontri, S. [Office of Atomic Energy for Peace, Bangkok (Thailand)

    1996-04-01

    Response characteristics of the alanine-polystyrene dosimeter were studied at an absorbed dose of 5 kGy over the low irradiation temperature range -196 {approx} 30{sup o}C, and the ESR analysis temperature range 0 {approx}50{sup o}C in the dose range 0.1 {approx} 10 kGy. The irradiation temperature coefficient previously estimated for the temperature range from 0 {approx} 70{sup o}C (+0.24%/.{sup o}C) was verified down to -15{sup o}C, although about 8% lower values were obtained at -78 and -196{sup o}C based on the correction using the above coefficient. ESR intensity decreases with temperature during ESR analysis following the function of the reciprocal of absolute temperature based on Boltzmann`s constant. The average temperature coefficient for three different dose levels during ESR analysis of the alanine-polystyrene dosimeter is -0.25%/K in the temperature range 0 {approx} 50{sup o}C. (Author).

  17. ESR1/SYNE1 polymorphism and invasive epithelial ovarian cancer risk: an Ovarian Cancer Association Consortium study

    DEFF Research Database (Denmark)

    Doherty, Jennifer A; Rossing, Mary Anne; Cushing-Haugen, Kara L;

    2010-01-01

    We genotyped 13 single nucleotide polymorphisms (SNPs) in the estrogen receptor alpha gene (ESR1) region in three population-based case-control studies of epithelial ovarian cancer conducted in the United States, comprising a total of 1,128 and 1,866 non-Hispanic white invasive cases and controls...

  18. Common genetic variation in the Estrogen Receptor Beta (ESR2) gene and osteoarthritis: Results of a meta-analysis

    NARCIS (Netherlands)

    J.M. Kerkhof (Hanneke); I. Meulenbelt (Ingrid); A. Gonzalez (Antonio); D.J. Hart (Deborah); A. Hofman (Albert); M. Kloppenburg (Margreet); N.E. Lane; J. Loughlin (John); M.C. Nevitt (Michael); H.A.P. Pols (Huib); F. Rivadeneira Ramirez (Fernando); E. Slagboom (Eline); T.D. Spector (Tim); L. Stolk (Lisette); A. Tsezou (Aspasia); A.G. Uitterlinden (André); A.M. Valdes (Ana Maria); J.B.J. van Meurs (Joyce); A.J. Carr (Andrew Jonathan)

    2010-01-01

    textabstractBackground: The objective of this study was to examine the relationship between common genetic variation of the ESR2 gene and osteoarthritis.Methods: In the discovery study, the Rotterdam Study-I, 7 single nucleotide polymorphisms (SNPs) were genotyped and tested for association with hip

  19. Spectroscopy of defects in HPHT and CVD diamond by ESR and pulsed photo-ionization measurements

    International Nuclear Information System (INIS)

    Synthetic diamond is one of the most promising wide band-gap materials for fabrication of solar-blind photo-sensors and radiation tolerant particle detectors. However, defects introduced during crystal growth and processing, causing carrier trapping and recombination, limit the functional characteristics of devices made of this material. In order to reveal the predominant defects, pulsed photo-ionization (PPI), Fourier transform infrared (FTIR) and electron spin resonance (ESR) spectroscopic measurements have been performed on diamond samples grown by chemical vapor deposition (CVD) and high pressure-high temperature (HPHT) methods. Measured photo-activation energies have been assigned to point defects associated with nitrogen and nickel impurities as well as to their complexes involving vacancies

  20. An ESR study of irradiated poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA)

    International Nuclear Information System (INIS)

    Poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) with 2 mol% perfluoropropyl vinyl ether (PPVE) was exposed to γ-irradiation in vacuum at both 77 K and room temperature and the ESR spectra recorded. Both the main chain, ∼CF2-C.F-CF2∼, and end chain, ∼CF2C.F2 radicals were identified at both temperatures and their thermal stabilities measured. No radicals unique to the radiolytic cleavage at the PPVE units were observed at room temperature, either due to the low concentration of the comonomer or β-scission to form a chain end radical and a non-radical species. G-values for radical formation at room temperature and 77 K were found to be 0.93 and 0.16, respectively

  1. OD ESR detection of the radical anions of cyclic nitrones in liquid solutions

    Science.gov (United States)

    Barlukova, M. M.; Gritsan, N. P.; Bagryansky, V. A.; Starichenko, V. F.; Grigor'ev, I. A.; Molin, Yu. N.

    2005-01-01

    The radical anions of five-membered cyclic nitrone spin traps, 3,3,5,5-tetramethyl-1-pyrroline-1-oxide and 1,2,2,5,5-pentamethyl-3-imidazoline-3-oxide, formed under radiolysis of liquid squalane solutions at 250-268 K, were registered by the method of optically detected ESR, and the hfc constants and g-values of the radical anions were determined. The hfc constants of these radical anions were predicted by DFT calculations and were found to be in quantitative agreement with experiment. It was demonstrated that radical anions of the five-membered cyclic nitrones have non-planar geometry with the spin density localized in the C dbnd N sbnd O fragment.

  2. ESR analysis of free radicals in a (solid) green tea phenolic extract

    International Nuclear Information System (INIS)

    Full text: A solid extract of procyanidins from green tea was studied by ESR, using a Varian E-12 (X-band: ∼9.1 GHz) spectrometer, at room temperature, and liquid N2 temperature. The spectrum consisted of three unstructured lines, one ∼20 gauss wide, one ∼ 10 gauss wide, and one ∼3 gauss wide. Saturation behaviour of these lines at room and liquid N2 temperature showed them to be from different radicals. About 50% of the extract is epogallocatechin gallate (EGCG). Using a pure sample of EGCG, it was possible to assign the broadest and strongest 'single' signal to EGCG. It has not been possible yet to assign the other lines to other molecular species

  3. Organ dose conversions from ESR measurements using tooth enamel of atomic bomb survivors.

    Science.gov (United States)

    Takahashi, Fumiaki; Sato, Kaoru

    2012-03-01

    Dose conversions were studied for dosimetry of atomic bomb survivors based upon electron spin resonance (ESR) measurements of tooth enamel. Previously analysed data had clarified that the tooth enamel dose could be much larger than other organ doses from a low-energy photon exposure. The radiation doses to other organs or whole-body doses, however, are assumed to be near the tooth enamel dose for photon energies which are dominant in the leakage spectrum of the Hiroshima atomic bomb assumed in DS02. In addition, the thyroid can be a candidate for a surrogate organ in cases where the tooth enamel dose is not available in organ dosimetry. This paper also suggests the application of new Japanese voxel phantoms to derive tooth enamel doses by numerical analyses. PMID:22128360

  4. ESR spectra of the olive phenolics oleuropein and keracyanin in the solid state

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, C.R. [Monash University, Clayton, VIC (Australia). Anatomy Department; Troup, G.J.; Hutton, D.R. [Monash University, Clayton, VIC (Australia). Physics Department; Hewitt, D.J. [Monash University, Clayton, VIC (Australia). Chemistry Department; Romani, A.; Mulinacci, N.; Vincieri, F.F. [Universita degli Studi, Firenze (Italy). Dipartimento di Scienze Farmaceutiche

    1998-12-31

    Full text: Olives and extra virgin olive oil, are known to be very rich in antioxidants, most of which are phenolics, such as oleuropein, a derivative of catechol: the `catechol` ring is separated, and effectively isolated electrically from the other (6-sided) ring. The main anthocyanin in olives in keracyanin (cyanidin-3-0-rutinoside). Solid samples of these two phenolics, and of catechol, were examined by ESR using a Varian E-12 spectrometer (x-band: {approx}9.1 GHz) at room temperature. All three samples gave single unstructured lines of {approx} 10g. width with g-vales close to 2. The presence of these free radical signal shows the antioxidant action of these phenolics, even in the solid state. We believe this is first observation of free radicals in olive phenolics

  5. ESR dating of late Cenozoic molassic deposits in the Jiuxi Basin

    Institute of Scientific and Technical Information of China (English)

    史正涛; 业渝光; 赵志军; 方小敏; 李吉均

    2001-01-01

    In the Hexi Corridor, foreland depression at the north periphery of the Tibetan Plateau, late Cenozoic sediments can be divided into the lacustrine to deltaic Red Bed. The unconformably overlying coarse fan-conglomerate was shed from the northern plateau. This remarkable alternation of sedimentary environment and discontinuity reflect intensive rise of the plateau. Moreover, this suite of coarse molasses is divided into two formations as the Yumen conglomerate and the Jiuquan Gravel by another angular discontinuity. Tentatively, we applied ESR dating on this suite of molassic deposits at the Laojunmiao Section in the Jiuxi Basin, west of the Hexi Corridor, which shows that the bottom of the Yumen conglomerate and the Jiuquan Gravel are about 3.4 and 0.9 Ma respectively, indicating that the northern plateau at least experienced two intensive tectonic movements at about 3.5 and 0.9 Ma.

  6. Dosimetry of electron and gamma radiation with alanine/ESR spectroscopy

    International Nuclear Information System (INIS)

    A new method for the preparation of alanine dosimeters was investigated. The absorbed dose response of these dosimeters was demonstrated for 10 MeV electron and 60Co gamma radiation in the range from 20 Gy to 1.1 kGy. Concentration of the irradiation-induced free radicals in the alanine was determined by ESR spectroscopy. In addition to measurements at ambient temperature, the alanine dosimeters were also subjected to thermal treatment during irradiation (up to about 50 deg. C) in order to assess their performance characteristics under extreme conditions which might arise in future technical applications. The results show that under normal conditions the alanine calibration curves are linear, whereas at higher temperatures the dosimeters require a correction of 0.3%/K for absorbed doses above 200 Gy. (author)

  7. ESR/L-alanine system as a proposed standard dosimeter for electron-beam irradiations

    International Nuclear Information System (INIS)

    The ESR/L-alanine system is a promising dosimeter, as it is characterized by high precision, stable dosimetric response, low value of G(freeradical) and non-toxicity. The scattering and absorption of γ radiation and fast electrons are equivalent for the system, for soft biological tissues, and for water. The possibility of further standardizations of the alanine dosimeter has now been proposed, not only as previously for γ radiation, but also for high-energy electron beam processing which brings high dose rates and side-effect problems. On the basis of the experimental results it seems reasonable to propose a new and more precise approximation of the functional shape describing the response of the L-alanine dosimeter and to express it directly by the radiation chemical yield of free radicals. (author)

  8. ESR/L-alanine system as a proposed standard dosimeter for electron-beam irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Panta, P.P.; Strzelczak-Burlinska, G.; Tomasinski, Z. (Institute of Nuclear Chemistry and Technology, Warsaw (Poland))

    1989-01-01

    The ESR/L-alanine system is a promising dosimeter, as it is characterized by high precision, stable dosimetric response, low value of G{sub (free} {sub radical)} and non-toxicity. The scattering and absorption of {gamma} radiation and fast electrons are equivalent for the system, for soft biological tissues, and for water. The possibility of further standardizations of the alanine dosimeter has now been proposed, not only as previously for {gamma} radiation, but also for high-energy electron beam processing which brings high dose rates and side-effect problems. On the basis of the experimental results it seems reasonable to propose a new and more precise approximation of the functional shape describing the response of the L-alanine dosimeter and to express it directly by the radiation chemical yield of free radicals. (author).

  9. Alanine in high-dose dosimetry: spectrophotometric and electrochemical readout procedures compared with ESR

    Energy Technology Data Exchange (ETDEWEB)

    Van Laere, K.; Buysse, J.; Berkvens, P. (Ghent Rijksuniversiteit (Belgium). Lab. voor Kernfysica)

    1989-01-01

    The ESR readout of radical concentrations produced upon irradiation of {alpha}-alanine is compared and related to other physico-chemical detection methods. Dissolution of the free radicals in an acid ferrous sulphate solution leads to an indirect oxidation of ferrous ions. After complex formation with the dye xylenol orange optical absorption measurements can be made within a dose range from 0.03 to 12 kGy. The yield of ammonia, produced upon dissolution in a basic aqueous solution, provides spectrophotometric evaluations after complex formation with a mercury iodide containing reagent for the dose range 5 kGy to 1 MGy. A practical new routine dosimeter for applications in the range 300 Gy to at least 1 MGy, by means of an ion-selective ammonia electrode, is proposed. (author).

  10. Spin Dynamics in Graphene and Graphene like Nanocarbon Doped with Nitrogen the ESR Analysis

    CERN Document Server

    Alegaonkar, Ashwini P; Pardeshi, Satish K; Alegaonkar, Prashant S

    2013-01-01

    Nano engineered spin degree of freedom in carbon system may offer desired exchange coupling with optimum spin orbit interaction which is essential, to construct solid state qubits, for fault tolerant quantum computation. The purpose of this communication is to analyze spin dynamics of, basically, four types of systems, (i) Graphene (system with inversion symmetry), (ii) Graphene like nanocarbons (GNCs, broken inversion symmetry and heterostructure, sp2 and sp3, environment), and (iii) their nitrogen doped derivatives. The spin transport data was obtained using the electron spin resonance spectroscopy (ESR) technique, carried out over 123 to 473K temperature range. Analysis of shape, linewidths of dispersion derivatives,, and g factor anisotropy has been carried out. Spin parameters such as, spin spin relaxation time, spin lattice relaxation time, spin flip parameter,spin relaxation rate,spin, momentum relaxation rate,pseudo chemical potential, density of states, effective magnetic moment, spin concentration, ...

  11. Wavefront Modulation and Subwavelength Diffractive Acoustics with an Acoustic Metasurface

    OpenAIRE

    Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A.

    2014-01-01

    Metasurfaces are a family of novel wavefront shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality as their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a desig...

  12. ACOUSTICS IN ARCHITECTURAL DESIGN, AN ANNOTATED BIBLIOGRAPHY ON ARCHITECTURAL ACOUSTICS.

    Science.gov (United States)

    DOELLE, LESLIE L.

    THE PURPOSE OF THIS ANNOTATED BIBLIOGRAPHY ON ARCHITECTURAL ACOUSTICS WAS--(1) TO COMPILE A CLASSIFIED BIBLIOGRAPHY, INCLUDING MOST OF THOSE PUBLICATIONS ON ARCHITECTURAL ACOUSTICS, PUBLISHED IN ENGLISH, FRENCH, AND GERMAN WHICH CAN SUPPLY A USEFUL AND UP-TO-DATE SOURCE OF INFORMATION FOR THOSE ENCOUNTERING ANY ARCHITECTURAL-ACOUSTIC DESIGN…

  13. Practical acoustic emission testing

    CERN Document Server

    2016-01-01

    This book is intended for non-destructive testing (NDT) technicians who want to learn practical acoustic emission testing based on level 1 of ISO 9712 (Non-destructive testing – Qualification and certification of personnel) criteria. The essential aspects of ISO/DIS 18436-6 (Condition monitoring and diagnostics of machines – Requirements for training and certification of personnel, Part 6: Acoustic Emission) are explained, and readers can deepen their understanding with the help of practice exercises. This work presents the guiding principles of acoustic emission measurement, signal processing, algorithms for source location, measurement devices, applicability of testing methods, and measurement cases to support not only researchers in this field but also and especially NDT technicians.

  14. Passive broadband acoustic thermometry

    Science.gov (United States)

    Anosov, A. A.; Belyaev, R. V.; Klin'shov, V. V.; Mansfel'd, A. D.; Subochev, P. V.

    2016-04-01

    The 1D internal (core) temperature profiles for the model object (plasticine) and the human hand are reconstructed using the passive acoustothermometric broadband probing data. Thermal acoustic radiation is detected by a broadband (0.8-3.5 MHz) acoustic radiometer. The temperature distribution is reconstructed using a priori information corresponding to the experimental conditions. The temperature distribution for the heated model object is assumed to be monotonic. For the hand, we assume that the temperature distribution satisfies the heat-conduction equation taking into account the blood flow. The average error of reconstruction determined for plasticine from the results of independent temperature measurements is 0.6 K for a measuring time of 25 s. The reconstructed value of the core temperature of the hand (36°C) generally corresponds to physiological data. The obtained results make it possible to use passive broadband acoustic probing for measuring the core temperatures in medical procedures associated with heating of human organism tissues.

  15. Acoustics waves and oscillations

    CERN Document Server

    Sen, S.N.

    2013-01-01

    Parameters of acoustics presented in a logical and lucid style Physical principles discussed with mathematical formulations Importance of ultrasonic waves highlighted Dispersion of ultrasonic waves in viscous liquids explained This book presents the theory of waves and oscillations and various applications of acoustics in a logical and simple form. The physical principles have been explained with necessary mathematical formulation and supported by experimental layout wherever possible. Incorporating the classical view point all aspects of acoustic waves and oscillations have been discussed together with detailed elaboration of modern technological applications of sound. A separate chapter on ultrasonics emphasizes the importance of this branch of science in fundamental and applied research. In this edition a new chapter ''Hypersonic Velocity in Viscous Liquids as revealed from Brillouin Spectra'' has been added. The book is expected to present to its readers a comprehensive presentation of the subject matter...

  16. Acoustic detection of pneumothorax

    Science.gov (United States)

    Mansy, Hansen A.; Royston, Thomas J.; Balk, Robert A.; Sandler, Richard H.

    2003-04-01

    This study aims at investigating the feasibility of using low-frequency (pneumothorax detection were tested in dogs. In the first approach, broadband acoustic signals were introduced into the trachea during end-expiration and transmitted waves were measured at the chest surface. Pneumothorax was found to consistently decrease pulmonary acoustic transmission in the 200-1200-Hz frequency band, while less change was observed at lower frequencies (ppneumothorax states (pPneumothorax was found to be associated with a preferential reduction of sound amplitude in the 200- to 700-Hz range, and a decrease of sound amplitude variation (in the 300 to 600-Hz band) during the respiration cycle (pPneumothorax changed the frequency and decay rate of percussive sounds. These results imply that certain medical conditions may be reliably detected using appropriate acoustic measurements and analysis. [Work supported by NIH/NHLBI #R44HL61108.

  17. A Century of Acoustic Metrology

    DEFF Research Database (Denmark)

    Rasmussen, Knud

    1998-01-01

    The development in acoustic measurement technique over the last century is reviewed with special emphasis on the metrological aspect.......The development in acoustic measurement technique over the last century is reviewed with special emphasis on the metrological aspect....

  18. Advanced Active Acoustics Lab (AAAL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Active Acoustics Lab (AAAL) is a state-of-the-art Undersea Warfare (USW) acoustic data analysis facility capable of both active and passive underwater...

  19. Densitometry By Acoustic Levitation

    Science.gov (United States)

    Trinh, Eugene H.

    1989-01-01

    "Static" and "dynamic" methods developed for measuring mass density of acoustically levitated solid particle or liquid drop. "Static" method, unknown density of sample found by comparison with another sample of known density. "Dynamic" method practiced with or without gravitational field. Advantages over conventional density-measuring techniques: sample does not have to make contact with container or other solid surface, size and shape of samples do not affect measurement significantly, sound field does not have to be know in detail, and sample can be smaller than microliter. Detailed knowledge of acoustic field not necessary.

  20. Acoustic classification of dwellings

    DEFF Research Database (Denmark)

    Berardi, Umberto; Rasmussen, Birgit

    2014-01-01

    insulation performance, national schemes for sound classification of dwellings have been developed in several European countries. These schemes define acoustic classes according to different levels of sound insulation. Due to the lack of coordination among countries, a significant diversity in terms...... of descriptors, number of classes, and class intervals occurred between national schemes. However, a proposal “acoustic classification scheme for dwellings” has been developed recently in the European COST Action TU0901 with 32 member countries. This proposal has been accepted as an ISO work item. This paper...

  1. Strong acoustic wave action

    Science.gov (United States)

    Gokhberg, M. B.

    1983-07-01

    Experiments devoted to acoustic action on the atmosphere-magnetosphere-ionosphere system using ground based strong explosions are reviewed. The propagation of acoustic waves was observed by ground observations over 2000 km in horizontal direction and to an altitude of 200 km. Magnetic variations up to 100 nT were detected by ARIEL-3 satellite near the epicenter of the explosion connected with the formation of strong field aligned currents in the magnetosphere. The enhancement of VLF emission at 800 km altitude is observed.

  2. Structural Acoustics and Vibrations

    Science.gov (United States)

    Chaigne, Antoine

    This structural chapter is devoted to vibrations of structures and to their coupling with the acoustic field. Depending on the context, the radiated sound can be judged as desirable, as is mostly the case for musical instruments, or undesirable, like noise generated by machinery. In architectural acoustics, one main goal is to limit the transmission of sound through walls. In the automobile industry, the engineers have to control the noise generated inside and outside the passenger compartment. This can be achieved by means of passive or active damping. In general, there is a strong need for quieter products and better sound quality generated by the structures in our daily environment.

  3. Variable-Position Acoustic Levitation

    Science.gov (United States)

    Barmatz, M. B.; Stoneburner, J. D.; Jacobi, N.; Wang, T. G.

    1983-01-01

    Method of acoustic levitation supports objects at positions other than acoustic nodes. Acoustic force is varied so it balances gravitational (or other) force, thereby maintaining object at any position within equilibrium range. Levitation method applicable to containerless processing. Such objects as table-tennis balls, hollow plastic spheres, and balsa-wood spheres levitated in laboratory by new method.

  4. An improved method for detection of Edwardsiella tarda by loop-mediated isothermal amplification by targeting the EsrB gene

    Institute of Scientific and Technical Information of China (English)

    XIE Guosi; ZHANG Qingli; HAN Nana; SHI Chengyin; WANG Xiuhua; LIU Qinghui; HUANG Jie

    2012-01-01

    Edwardsiella tarda is a major pathogen in aquatic environments that can cause heavy economic losses.An improved method for quick and accurate detection of E.tarda by loop-mediated isothermal amplification (LAMP) with two additional loop primers was developed by targeting the EsrB gene (EsrBLAMP).In this method,the Mg2+ concentration,reaction temperature,and reaction time were optimized to 8 mmol/L,61℃,and 40 min,respectively.The detection limit with the EsrB gene was as low as 10 copies,which is 100 times more sensitive than that of conventional polymerase chain reaction (PCR).The EsrB-LAMP assay was shown more sensitive and rapid than previously reported LAMP assays targeting the hemolysin gene (hemolysin-LAMP) for detection ofE.tarda.The EsrB-LAMP was also highly specific to E.tarda and had no cross-reaction with 13 other strains of bacteria.The assay can be carried out in a simple heating device and the EsrB-LAMP products can be visually detected by adding fluorescent dye to the reaction mixture.Taken together,the improved EsrB-LAMP diagnostic protocol has the potential for detection ofE.tarda from indoor and outdoor samples.

  5. The Arabidopsis KH-Domain RNA-Binding Protein ESR1 Functions in Components of Jasmonate Signalling, Unlinking Growth Restraint and Resistance to Stress.

    Directory of Open Access Journals (Sweden)

    Louise F Thatcher

    Full Text Available Glutathione S-transferases (GSTs play important roles in the protection of cells against toxins and oxidative damage where one Arabidopsis member, GSTF8, has become a commonly used marker gene for early stress and defense responses. A GSTF8 promoter fragment fused to the luciferase reporter gene was used in a forward genetic screen for Arabidopsis mutants with up-regulated GSTF8 promoter activity. This identified the esr1-1 (enhanced stress response 1 mutant which also conferred increased resistance to the fungal pathogen Fusarium oxysporum. Through positional cloning, the ESR1 gene was found to encode a KH-domain containing RNA-binding protein (At5g53060. Whole transcriptome sequencing of esr1-1 identified altered expression of genes involved in responses to biotic and abiotic stimuli, hormone signaling pathways and developmental processes. In particular was an overall significant enrichment for jasmonic acid (JA mediated processes in the esr1-1 down-regulated dataset. A subset of these genes were tested for MeJA inducibility and we found the expression of some but not all were reduced in esr1-1. The esr1-1 mutant was not impaired in other aspects of JA-signalling such as JA- sensitivity or development, suggesting ESR1 functions in specific components of the JA-signaling pathway. Examination of salicylic acid (SA regulated marker genes in esr1-1 showed no increase in basal or SA induced expression suggesting repression of JA-regulated genes is not due to antagonistic SA-JA crosstalk. These results define new roles for KH-domain containing proteins with ESR1 unlinking JA-mediated growth and defense responses.

  6. From Architectural Acoustics to Acoustical Architecture Using Computer Simulation

    DEFF Research Database (Denmark)

    Schmidt, Anne Marie Due; Kirkegaard, Poul Henning

    2005-01-01

    Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic...... properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to investigate the field of application that an acoustic simulation programme can have during an architectural...... acoustic design process and to set up a strategy to develop future programmes. The emphasis is put on the first three out of four phases in the working process of the architect and a case study is carried out in which each phase is represented by typical results ? as exemplified with reference...

  7. Underwater Acoustic Networking Techniques

    CERN Document Server

    Otnes, Roald; Casari, Paolo; Goetz, Michael; Husøy, Thor; Nissen, Ivor; Rimstad, Knut; van Walree, Paul; Zorzi, Michele

    2012-01-01

    This literature study presents an overview of underwater acoustic networking. It provides a background and describes the state of the art of all networking facets that are relevant for underwater applications. This report serves both as an introduction to the subject and as a summary of existing protocols, providing support and inspiration for the development of network architectures.

  8. Evoked acoustic emission

    DEFF Research Database (Denmark)

    Elberling, C; Parbo, J; Johnsen, N J;

    1985-01-01

    Stimulated acoustic emissions were recorded in response to tonal stimuli at 60 dB p.e. SPL in a small group of normal-hearing adults. Power spectral analysis reveals that the evoked activity from each ear contains energy in preferential frequency bands and the change of stimulus frequency has only...

  9. Surface Acoustic Wave Devices

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard

    The work of this project is concerned with the simulation of surface acoustic waves (SAW) and topology optimization of SAW devices. SAWs are elastic vibrations that propagate along a material surface and are extensively used in electromechanical filters and resonators in telecommunication. A new...

  10. Portable acoustic myography

    DEFF Research Database (Denmark)

    Harrison, Adrian Paul; Danneskiold-Samsøe, Bente; Bartels, Else Marie

    2013-01-01

    Muscle sound gives a local picture of muscles involved in a particular movement and is independent of electrical signals between nerve and muscle. Sound recording (acoustic myography) is a well-known noninvasive technique that has suffered from not being easily applicable, as well as not being ab...

  11. ESR phase competition study of Pr0.5(Ca0.85Sr0.15)0.5MnO3

    International Nuclear Information System (INIS)

    We report an electron spin resonance (ESR) study of the competing phases at the crossover from localized to itinerant behaviour on the polycrystalline Pr0.5(Ca0.85Sr0.15)0.5MnO3 compounds. From the temperature dependence of the ESR intensity, we derived the transition temperatures to charge order (TCO=230 K), and antiferromagnetic (TN=150 K) states. In addition, at T<200 K, a ferromagnetic minority phase was found, that coexists with the paramagnetic and antiferromagnetic phases. We perform simulations of the ESR spectra that reproduce the behaviour found at different temperatures

  12. ESR analyses for teeth from the open-air site at Attirampakkam, India: Clues to complex U uptake and paleoenvironmental change

    International Nuclear Information System (INIS)

    In open-air sites, diagenetic alteration makes teeth difficult to analyze with electron spin resonance (ESR). Despite strong diagenetic alteration, three ungulate teeth from Pleistocene fluvial sediment in the open-air Paleolithic site at Attirampakkam, Tamil Nadu, India, were analyzed using standard and isochron ESR. Diagenetic alteration features in two teeth indicated rapid submergence in quiet saline to hypersaline water, following a short subaerial exposure, while the third remained constantly buried under reducing conditions. Geochemical signatures and ESR data all indicate that the teeth experienced at least three independent U uptake events during diagenesis, including two that occurred long after burial

  13. Holograms for acoustics

    Science.gov (United States)

    Melde, Kai; Mark, Andrew G.; Qiu, Tian; Fischer, Peer

    2016-09-01

    Holographic techniques are fundamental to applications such as volumetric displays, high-density data storage and optical tweezers that require spatial control of intricate optical or acoustic fields within a three-dimensional volume. The basis of holography is spatial storage of the phase and/or amplitude profile of the desired wavefront in a manner that allows that wavefront to be reconstructed by interference when the hologram is illuminated with a suitable coherent source. Modern computer-generated holography skips the process of recording a hologram from a physical scene, and instead calculates the required phase profile before rendering it for reconstruction. In ultrasound applications, the phase profile is typically generated by discrete and independently driven ultrasound sources; however, these can only be used in small numbers, which limits the complexity or degrees of freedom that can be attained in the wavefront. Here we introduce monolithic acoustic holograms, which can reconstruct diffraction-limited acoustic pressure fields and thus arbitrary ultrasound beams. We use rapid fabrication to craft the holograms and achieve reconstruction degrees of freedom two orders of magnitude higher than commercial phased array sources. The technique is inexpensive, appropriate for both transmission and reflection elements, and scales well to higher information content, larger aperture size and higher power. The complex three-dimensional pressure and phase distributions produced by these acoustic holograms allow us to demonstrate new approaches to controlled ultrasonic manipulation of solids in water, and of liquids and solids in air. We expect that acoustic holograms will enable new capabilities in beam-steering and the contactless transfer of power, improve medical imaging, and drive new applications of ultrasound.

  14. Controlling sound with acoustic metamaterials

    DEFF Research Database (Denmark)

    Cummer, Steven A. ; Christensen, Johan; Alù, Andrea

    2016-01-01

    Acoustic metamaterials can manipulate and control sound waves in ways that are not possible in conventional materials. Metamaterials with zero, or even negative, refractive index for sound offer new possibilities for acoustic imaging and for the control of sound at subwavelength scales....... The combination of transformation acoustics theory and highly anisotropic acoustic metamaterials enables precise control over the deformation of sound fields, which can be used, for example, to hide or cloak objects from incident acoustic energy. Active acoustic metamaterials use external control to create......-scale metamaterial structures and converting laboratory experiments into useful devices. In this Review, we outline the designs and properties of materials with unusual acoustic parameters (for example, negative refractive index), discuss examples of extreme manipulation of sound and, finally, provide an overview...

  15. Esrâr Dede Divanı’nda Renkler Colours In Dıvan Of Esrâr Dede

    Directory of Open Access Journals (Sweden)

    Mahmut KAPLAN

    2013-03-01

    Full Text Available Esrâr Dede is one of significant figures of our classical poetry. After becoming affiliated with Mevleviyeh, he embarked upon poetry, bringing forth remarkable works. He made friends with Şeyh Galib. The poet has a collection of biographies and dictionary as well as a divan. Esrar Dede frequently used words which expressed colours in order toexplain his feelings and thoughts. The words of colours are alsoimportant bearers of cultural heritage. Colours which are used indescription and definition of entities gain representative meanings insome texts (of the society, too. It is known that some colours statedirections in Turkish. At times, colours are used to express feelings;they reflect people’s mood. Colours are the most important means poetshave to depict sceneries of nature. A poet displays the nature throughwords of colour, and expresses their feelings and thoughts withinsymbolic expressions by means of colours. In depictions made in prosesof eulogiums, colours have important roles. Esrar Dede, most of whoseodes are affectionate, also applied adjectives of colour to express hisfeelings and thoughts. Black and red are especially seen aspredominant colours in Esrar Dede Divan. These colours were used todepict entities and express some sufistic situations. Black is generallyseen in the descriptions of night, hair, and darkness. Moreover, thiscolour is applied to depict situations such as bad fortune andmischance. Red is seen in depictions of rose, dawn, blood, and lips.Except these two main colours, white, yellow, green; andcolournessness and lack of colour which express sufistic situations tookplace among the colours the poet used. When it is taken into accountthat Esrar Dede was a Mevlevi, it will be understood how importantcolours are in his poetry. In this article, Esrar Dede’s perception ofcolour was tried to determine by evaluating the colours he used withintheir contexts in the text. The colours have been arranged andinvestigated in

  16. Irradiation dose control of chicken meat processing with alanine/ESR dosimetric system

    Energy Technology Data Exchange (ETDEWEB)

    Miyagusku, L. [Centro de Tecnologia de Carnes, Instituto de Tecnologia de Alimentos. Av. Brasil, 2880 13074-001 Campinas, SP (Brazil); Chen, F. [Departmento de Fisica e Matematica, FFCLRP - Universidade de Sao Paulo, 14040-901, Ribeirao Preto - SP (Brazil); Kuaye, A. [Departamento de Tecnologia de Alimentos, Universidade de Campinas, Campinas - SP (Brazil); Castilho, C.J.C. [Departamento de Agroindustria, ESALQ, Piracicaba - SP (Brazil); Baffa, O. [Departmento de Fisica e Matematica, FFCLRP - Universidade de Sao Paulo, 14040-901, Ribeirao Preto - SP (Brazil)], E-mail: baffa@ffclrp.usp.br

    2007-07-15

    Irradiation of foodstuff is a well-known food preservation technique. In Brazil spices are already irradiated for sanitary and preservation reasons. Chicken meat is an important commodity; Brazil is the second largest world producer and the largest world exporter. The shelf-life of chicken meat is limited by the presence of micro-organisms and enzyme activity and together with other preservation techniques irradiation seems to be an attractive option. In this study the dose delivered to frozen chicken cuts was measured and compared with the prescribed value. Chicken breast cuts were analyzed for 39 days for their microbiological activity, chemical and organoleptic properties. Cylindrical dosimeters were prepared using the weight composition of 80% of DL-alanine (Sigma Co), used without any further treatment except drying, and 20% of paraffin. The dosimeters having 4.7 mm diameter and 12 mm length were inserted in a build-up cap. Dosimeters were placed inside cardboard boxes containing frozen chicken breast cuts, packed in styrofoam trays wrapped with plastic film. The boxes were irradiated in an industrial {sup 60}Co irradiator (Nordion JS 7500) with a dose rate of 4 kGy/h. First derivative ESR signals were obtained in a VARIAN E-4 spectrometer operating at X-band ({nu}{approx}9GHz) and equipped with a rectangular cavity (TE-102, model E-231). The cavity was constantly purged with dry nitrogen and modulated at 100 KHz with 0.5 mT peak to peak. A calibration curve was made for a few dosimeters from the same batch and used to obtain the dose from the ESR signal intensity. A batch of six boxes was irradiated at each experiment with prescribed doses of 1.5, 3.0 and 7.0 kGy. Considering that the larger the radiation dose the greater is the probability of finding a product with its sensorial characteristics altered (odor of burned meat), we conclude that a dose of 3 kGy would be more adequate, taking into account the microbiological and sensorial aspects.

  17. Studi Spektroskopi Electron Spin Resonance (Esr Lapisan Tipis Amorf Silikon Karbon (A-Sic:H Hasil Deposisi Metode Dc Sputtering

    Directory of Open Access Journals (Sweden)

    Rosari Saleh

    2002-04-01

    Full Text Available The dangling bond defect density in sputtered amorphous silicon carbon alloys have been studied by electron spin resonance (ESR. The results show that the spin density decreased slightly with increasing methane fl ow rate (CH4. The infl uence of carbon and hydrogen incorporation on g-value revealed that for CH4 fl ow rate up to 8 sccm, the ESR signal is dominated by defects characteristic of a-Si:H fi lms and for CH4 fl ow rate higher than 8 sccm the g-value decreased towards those usually found in a-C:H fi lms. Infrared (IR results suggest that as CH4 fl ow rate increases more carbon and hydrogen is incorporated into the fi lms to form Si-H, Si-C and C-H bonds. A direct relation between the IR results and the defect density and g-value is observed.

  18. Charge carrier behavior in UV irradiated fullerene nano whiskers based on studies of electrical conduction and ESR

    Science.gov (United States)

    Doi, Tatsuya; Koyama, Kyouhei; Bird, Jonathan P.; Aoki, Nobuyuki; Ochiai, Yuichi

    2011-12-01

    The UV light irradiation to C60 fullerene induces [2+2] cyclo-additional reaction, and creates inter-molecule bonds between C60 molecules. That reaction makes fullerene polymer from molecules. A fine crystalline wire structure consisting of C60 molecules is called a fullerene nano whisker (FNW), and also is used to fabricate n-type field effect transistors (FET) as the channel. The UV irradiation to the FNW-FET for polymerization must achieve the FET operation in ambient atmosphere. Here, a drastic changing of FET parameters has been observed. In the ESR measurement in ambient atmosphere, we have studied on temperature dependence of peak-to-peak width (ΔHPP) and ESR magnetic susceptibility ratio. The comparison, the temperature dependence of pristine FNW and UV irradiated FNW, clearly indicates that there exists a clearer difference in electronic state between pristine FNW and UV polymerized FNW.

  19. Flat acoustic lens by acoustic grating with curled slits

    KAUST Repository

    Peng, Pai

    2014-10-01

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry-Perot resonance.

  20. Acoustic energy harvesting based on a planar acoustic metamaterial

    Science.gov (United States)

    Qi, Shuibao; Oudich, Mourad; Li, Yong; Assouar, Badreddine

    2016-06-01

    We theoretically report on an innovative and practical acoustic energy harvester based on a defected acoustic metamaterial (AMM) with piezoelectric material. The idea is to create suitable resonant defects in an AMM to confine the strain energy originating from an acoustic incidence. This scavenged energy is converted into electrical energy by attaching a structured piezoelectric material into the defect area of the AMM. We show an acoustic energy harvester based on a meta-structure capable of producing electrical power from an acoustic pressure. Numerical simulations are provided to analyze and elucidate the principles and the performances of the proposed system. A maximum output voltage of 1.3 V and a power density of 0.54 μW/cm3 are obtained at a frequency of 2257.5 Hz. The proposed concept should have broad applications on energy harvesting as well as on low-frequency sound isolation, since this system acts as both acoustic insulator and energy harvester.

  1. Acoustics Discipline Overview

    Science.gov (United States)

    Envia, Edmane; Thomas, Russell

    2007-01-01

    As part of the Fundamental Aeronautics Program Annual Review, a summary of the progress made in 2007 in acoustics research under the Subsonic Fixed Wing project is given. The presentation describes highlights from in-house and external activities including partnerships and NRA-funded research with industry and academia. Brief progress reports from all acoustics Phase 1 NRAs are also included as are outlines of the planned activities for 2008 and all Phase 2 NRAs. N+1 and N+2 technology paths outlined for Subsonic Fixed Wing noise targets. NRA Round 1 progressing with focus on prediction method advancement. NRA Round 2 initiating work focused on N+2 technology, prediction methods, and validation. Excellent partnerships in progress supporting N+1 technology targets and providing key data sets.

  2. Acoustic Tractor Beam

    Science.gov (United States)

    Démoré, Christine E. M.; Dahl, Patrick M.; Yang, Zhengyi; Glynne-Jones, Peter; Melzer, Andreas; Cochran, Sandy; MacDonald, Michael P.; Spalding, Gabriel C.

    2014-05-01

    Negative radiation forces act opposite to the direction of propagation, or net momentum, of a beam but have previously been challenging to definitively demonstrate. We report an experimental acoustic tractor beam generated by an ultrasonic array operating on macroscopic targets (>1 cm) to demonstrate the negative radiation forces and to map out regimes over which they dominate, which we compare to simulations. The result and the geometrically simple configuration show that the effect is due to nonconservative forces, produced by redirection of a momentum flux from the angled sides of a target and not by conservative forces from a potential energy gradient. Use of a simple acoustic setup provides an easily understood illustration of the negative radiation pressure concept for tractor beams and demonstrates continuous attraction towards the source, against a net momentum flux in the system.

  3. Acoustic absorption by sunspots

    Science.gov (United States)

    Braun, D. C.; Labonte, B. J.; Duvall, T. L., Jr.

    1987-01-01

    The paper presents the initial results of a series of observations designed to probe the nature of sunspots by detecting their influence on high-degree p-mode oscillations in the surrounding photosphere. The analysis decomposes the observed oscillations into radially propagating waves described by Hankel functions in a cylindrical coordinate system centered on the sunspot. From measurements of the differences in power between waves traveling outward and inward, it is demonstrated that sunspots appear to absorb as much as 50 percent of the incoming acoustic waves. It is found that for all three sunspots observed, the amount of absorption increases linearly with horizontal wavenumber. The effect is present in p-mode oscillations with wavelengths both significantly larger and smaller than the diameter of the sunspot umbrae. Actual absorption of acoustic energy of the magnitude observed may produce measurable decreases in the power and lifetimes of high-degree p-mode oscillations during periods of high solar activity.

  4. Acoustic absorption by sunspots

    Energy Technology Data Exchange (ETDEWEB)

    Braun, D.C.; Labonte, B.J.; Duvall, T.L. Jr.

    1987-08-01

    The paper presents the initial results of a series of observations designed to probe the nature of sunspots by detecting their influence on high-degree p-mode oscillations in the surrounding photosphere. The analysis decomposes the observed oscillations into radially propagating waves described by Hankel functions in a cylindrical coordinate system centered on the sunspot. From measurements of the differences in power between waves traveling outward and inward, it is demonstrated that sunspots appear to absorb as much as 50 percent of the incoming acoustic waves. It is found that for all three sunspots observed, the amount of absorption increases linearly with horizontal wavenumber. The effect is present in p-mode oscillations with wavelengths both significantly larger and smaller than the diameter of the sunspot umbrae. Actual absorption of acoustic energy of the magnitude observed may produce measurable decreases in the power and lifetimes of high-degree p-mode oscillations during periods of high solar activity. 10 references.

  5. ROS evaluation for a series of CNTs and their derivatives using an ESR method with DMPO

    International Nuclear Information System (INIS)

    Carbon nanotubes (CNTs) are important materials in advanced industries. It is a concern that pulmonary exposure to CNTs may induce carcinogenic responses. It has been recently reported that CNTs scavenge ROS though non-carbon fibers generate ROS. A comprehensive evaluation of ROS scavenging using various kinds of CNTs has not been demonstrated well. The present work specifically investigates ROS scavenging capabilities with a series of CNTs and their derivatives that were physically treated, and with the number of commercially available CNTs. CNT concentrations were controlled at 0.2 through 0.6 wt%. The ROS scavenging rate was measured by ESR with DMPO. Interestingly, the ROS scavenging rate was not only influenced by physical treatments, but was also dependent on individual manufacturing methods. Ratio of CNTs to DMPO/ hydrogen peroxide is a key parameter to obtain appropriate ROS quenching results for comparison of CNTs. The present results suggest that dangling bonds are not a sole factor for scavenging, and electron transfer on the CNT surface is not clearly determined to be the sole mechanism to explain ROS scavenging.

  6. An ESR study of the gamma radiolysis of aromatic polyesters containing isomeric naphthalene links

    International Nuclear Information System (INIS)

    Six polyesters were synthesised from 4,4'-oxy-bis(benzoyl chloride) and 1,4-, 1,5-, 1,6-, 2,3-, 2,6-, and 2,7-naphthalenediol isomers. The structures of the polyesters were characterised by means of IR, inherent viscosities in tetrachloroethane (TCE), solutions at 303 K and thermal analysis. The glass transition temperatures were in the range of 425-494 K by DSC thermal analysis. All of the polyesters were irradiated in an AECL Gammacell 220 unit at a dose rate of approximately 6.7 kGy/h to doses in the range of 0-15 kGy at 77 and 300 K. ESR spectroscopy was used to examine the radicals formed during radiolysis and to measure their yields. The G-values for radical formation in the polyesters were found to be in the range 0.18-1.41 at 77 K and 0.19-0.78 at 300 K. At 77 K, up to 15% of the radicals formed on radiolysis were found to be photo-bleachable anion radicals. Annealing experiments were carried out in order to identify the neutral radicals, which were assigned to naphthyl- or phenyl- and phenoxyl-type radicals

  7. ESR investigation of NR and IR rubber vulcanized with different cross-link agents

    Directory of Open Access Journals (Sweden)

    P. Posadas

    2016-01-01

    Full Text Available This study evaluates the formation of radical species in natural rubber (NR and poly-isoprene rubber (IR during the vulcanization process and the uniaxial deformation of the formed networks by means of Electron Spin Resonance (ESR. Vulcanization of NR and IR always shows a radical pathway, where the different vulcanization systems dictate the concentration of radical species in the course of this complex process. The greatest concentration of radicals were detected during the vulcanization with sulfur/accelerator based on efficient systems (EV, followed by conventional (CV and sulfur donor systems, whereas azide and organic peroxide agents showed smaller concentration of radicals. Independently of the vulcanization system, certain amount of radicals was detected on the vulcanized samples after the end of the vulcanization process. Comparison between different matrices demonstrates that NR always shows higher concentration of radicals than IR in the vulcanization process as well as during uniaxial deformation, fact that could be associated to the presence of nonrubber components in NR.

  8. Testing cosmic dose rate models for ESR: Dating corals and molluscs on San Salvador, Bahamas

    Energy Technology Data Exchange (ETDEWEB)

    Deely, A.E. [RFK Science Research Institute, Glenwood Landing, NY, 11547-0866 (United States); Blackwell, B.A.B., E-mail: bonnie.a.b.blackwell@williams.edu [RFK Science Research Institute, Glenwood Landing, NY, 11547-0866 (United States); Dept. of Chemistry, Williams College, Williamstown MA, 01267-2692 (United States); Mylroie, J.E. [Dept. of Geosciences, Mississippi State University, MS, 39762-5448 (United States); Carew, J.L. [Dept. of Geology and Environmental Geosciences, College of Charleston, Charleston, SC 29424 (United States); Blickstein, J.I.B. [RFK Science Research Institute, Glenwood Landing, NY, 11547-0866 (United States); Skinner, A.R. [RFK Science Research Institute, Glenwood Landing, NY, 11547-0866 (United States); Dept. of Chemistry, Williams College, Williamstown MA, 01267-2692 (United States)

    2011-09-15

    Sealevel curves are best developed on tectonically stable coastlines, like San Salvador, where eolianites preserve transgressive and regressive phases associated with Quaternary high seastands, while reef facies mark the highstands. At 11 locations around San Salvador, terrestrial molluscs (Cerion) from the eolianites, lagoonal bivalves (Codakia), and corals from the highstand deposits were dated by ESR. Volumetrically averaged sedimentary dose rates were calculated from sedimentary geochemistry and time-averaged cosmic dose rates from each sample's current and past geologic contexts. Rice Bay Formation corals dated at 3.9 {+-} 0.3 to 7.1 {+-} 0.4 ka (OIS 1). Minimum ages for the Cockburn Town Member's regressive phase ranged from 49 {+-} 6 to 75 {+-} 8 ka, correlating with OIS 3-4. Codakia dates showed that an OIS 5a sealevel approached modern levels at 91-78 ka. In situ corals from the Cockburn Town Reef averaged from 127 {+-} 6 to 138 {+-} 10 ka, correlating well with OIS 5e. Ages from the Reef's rubble zones hint that some coral reefs grew as early as OIS 7, but were likely reworked during OIS 5. San Salvador preserves deposits from three mid to late Quaternary highstands above, and as many as three that closely approach, modern sealevel.

  9. Core curriculum for medical physicists in radiology. Recommendations from an EFOMP/ESR working group.

    Science.gov (United States)

    Geleijns, Jacob; Breatnach, Eamann; Cantera, Alfonso Calzado; Damilakis, John; Dendy, Philip; Evans, Anthony; Faulkner, Keith; Padovani, Renato; Van Der Putten, Wil; Schad, Lothar; Wirestam, Ronnie; Eudaldo, Teresa

    2012-06-01

    Some years ago it was decided that a European curriculum should be developed for medical physicists professionally engaged in the support of clinical diagnostic imaging departments. With this in mind, EFOMP (European Federation of Organisations for Medical Physics) in association with ESR (European Society of Radiology) nominated an expert working group. This curriculum is now to hand. The curriculum is intended to promote best patient care in radiology departments through the harmonization of education and training of medical physicists to a high standard in diagnostic radiology. It is recommended that a medical physicist working in a radiology department should have an advanced level of professional expertise in X-ray imaging, and additionally, depending on local availability, should acquire knowledge and competencies in overseeing ultrasound imaging, nuclear medicine, and MRI technology. By demonstrating training to a standardized curriculum, medical physicists throughout Europe will enhance their mobility, while maintaining local high standards of medical physics expertise. This document also provides the basis for improved implementation of articles in the European medical exposure directives related to the medical physics expert. The curriculum is divided into three main sections: The first deals with general competencies in the principles of medical physics. The second section describes specific knowledge and skills required for a medical physicist (medical physics expert) to operate clinically in a department of diagnostic radiology. The final section outlines research skills that are also considered to be necessary and appropriate competencies in a career as medical physicist. PMID:22696082

  10. ESR study of free radicals in UHMW-PE fiber irradiated by gamma rays

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Yanning [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, PO Box 800-204, Shanghai 201800 (China); College of Chemistry, Jilin Normal University, Jilin 136000 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China); Wang Mouhua [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, PO Box 800-204, Shanghai 201800 (China); Tang Zhongfeng [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, PO Box 800-204, Shanghai 201800 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China); Wu Guozhong, E-mail: wuguozhong@sinap.ac.c [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, PO Box 800-204, Shanghai 201800 (China)

    2010-04-15

    ESR spectra of the trapped radicals in an ultra-high molecular weight polyethylene (UHMW-PE) fiber irradiated by gamma rays showed well-resolved hyperfine splitting at room temperature since the c-axis of the crystallites is aligned with the fiber direction and the radicals are trapped in crystallites. The alkyl radical (-CH{sub 2}-{sup c}entre dotCH-CH{sub 2}-) was the major product after irradiation in vacuum and in air at room temperature. Some of the alkyl radicals converted to allyl radicals (-CH{sub 2}-{sup c}entre dotCH-CH=CH-) and polyenyl radicals (-CH{sub 2}-{sup c}entre dotCH-(CH=CH){sub n}-CH{sub 2}-) during storage in vacuum. Upon storage in air atmosphere, the alkyl radicals decayed by reaction with oxygen. Of particular interest is the very slow decay rate of the alkyl radical trapped in UHMW-PE fiber, the half-life is 26 days in vacuum, and 13 days in air at room temperature, which is about 1/30 and 1/100 of that reported for high density polyethylene (HDPE), respectively. The extremely long lifetime of the alkyl radical is supposed to be caused by the large size of crystallites in UHMW-PE fiber. The rate of radical decay was accelerated by annealing at elevated temperature.

  11. Spin dynamics of S = 1/2 kagome lattice antiferromagnets observed by high-field ESR

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Hitoshi [Molecular Photoscience Research Center, Kobe University, Kobe 657-8501 (Japan); Graduate School of Science, Kobe University, Kobe 657-8501 (Japan); Zhang, Wei-min [Graduate School of Science, Kobe University, Kobe 657-8501 (Japan); Okubo, Susumu; Fujisawa, Masashi [Molecular Photoscience Research Center, Kobe University, Kobe 657-8501 (Japan); Sakurai, Takahiro [Center for Supports to Research and Education Activities, Kobe University, Kobe 657-8501 (Japan); Okamoto, Yoshihiko; Yoshida, Hiroyuki; Hiroi, Zenji [Institute for Solid State Physics (ISSP), University of Tokyo, Kashiwa, Chiba 277-8581 (Japan)

    2010-03-15

    Due to the existence of strong spin frustration in a system, the spin dynamics of S = 1/2 kagome lattice antiferromagnet at low temperature has attracted much interest. High-field ESR has been measured on its model substances, Cu{sub 3}V{sub 2}O{sub 7}(OH){sub 2} . 2H{sub 2}O (volborthite) and BaCu{sub 3}V{sub 2}O{sub 3}(OH){sub 2} (vesignieite), down to 1.8 K using pulsed magnetic fields up to 16 T. The measurements are performed for 160 and 315 GHz using polycrys-talline samples. Although both samples showed the g-shift and the change of linewidth at low temperature, volborthite showed a small gap excitation of the order of 40 GHz (1.9 K) while vesignieite showed a paramagnetic behavior down to 1.9 K. Observed difference will be discussed in connection with the crystal structure, and the possible spin liquid state in vesignieite will be discussed. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  12. ESR detection of free radicals in polyphenolic extracts from wine grapes, olives and green tea

    International Nuclear Information System (INIS)

    Full text: Polyphenols are widespread in vegetables and fruits and they play an important role in human diet and health: these compounds act mainly as antioxidants and radical scavengers. In this work we have detected free radicals in the following natural polyphenols: Endotelon, an anthocyanic grapeskin extract; malvidin 3,5-O-diglucosides (malvin); oleuropein, an olive polyphenol; a commercial green tea extract, and pure epigallocatechingallate EGCG. The investigation was performed using a Varian E-12 ESR Spectrometer (∼9.1 GHz) at room temperature. All except the green tea extract gave single unstructured lines of ∼ 10 gauss linewidth. The tea extract signal showed 3 lines, one ∼ 20 gauss wide, one ∼ 10 gauss wide, and one ∼ 2-3 gauss wide. Saturation behaviour of these lines at room and liquid N2 temperature showed them to be from different radicals About 50% of the extract is represented by epigallocatechingallate (EGCG). Using the pure sample EGCG it was possible to assign the appropriate radical, which corresponded with the broadest and strongest 'single' signal (∼20g wide). The presence of the free radicals in the solid extracts shows that the appropriate molecules can act as radical scavengers by forming stable radicals

  13. Quaternary dating by electron spin resonance (ESR applied to human tooth enamel

    Directory of Open Access Journals (Sweden)

    Carvajal Eduar

    2011-12-01

    Full Text Available This paper presents the results obtained from using electron paramagnetic resonance (EPR to analyse tooth enamel found at the Aguazuque archaeological site (Cundinamarca, Colombia, located on the savannah near Bogota at 4° 37' North and 74°17' West. It was presumed that the tooth enamel came from a collective burial consisting of 23 people, involving men, women and children. The tooth enamel was irradiated with gamma rays and the resulting free radicals were measured using an electron spin resonance (ESR X-band spectrometer to obtain a signal intensity compared to absorbed doses curve. Fitting this curve allowed the mean archaeological dose accumulated in the enamel during the period that it was buried to be estimated, giving a 2.10 ± 0.14 Gyvalue. ROSY software was used for estimating age, giving a mean 3,256 ± 190y before present (BP age. These results highlight EPR's potential when using the quaternary ancient ruins dating technique in Colombia and its use with other kinds of samples like stalagmites, calcite, mollusc shells and reefs.

  14. Simultaneous high- and low-latitude reconnection: ESR and DMSP observations

    Directory of Open Access Journals (Sweden)

    F. Pitout

    Full Text Available We present EISCAT Svalbard Radar and DMSP observations of a double cusp during an interval of predominantly northward IMF on 26 November 2000. In the cusp region, the ESR dish, pointing northward, recorded sun-ward ionospheric flow at high latitudes (above 82° GL, indicating reconnection occuring in the magnetospheric lobe. Meanwhile, the same dish also recorded bursts of poleward flow, indicative of bursty reconnection at the subsolar magnetopause. Within this time interval, the DMSP F13 satellite passed in the close vicinity of the Svalbard archipelago. The particle measurement on board exhibited a double cusp structure in which two oppositely oriented ion dispersions are recorded. We interpret this set of data in terms of simultaneous merging at low- and high-latitude magnetopause. We discuss the conditions for which such simultaneous high-latitude and low-latitude reconnection can be anticipated. We also discuss the consequences of the presence of two X-lines in the dayside polar ionosphere.

    Key words. Magnetospheric physics (solar wind-magnetosphere interactions – Ionosphere (polar ionosphere; plasma convection

  15. ESR Studies on the Micellization Behaviors of a Series of Novel Asymmetric Gemini Surfactants

    Institute of Scientific and Technical Information of China (English)

    WU,Yi-Tian(吴一天); WANG,Jin-Ben(王金本); LIU,Ming-Hua(刘鸣华); LIANG,Wen-Ping(梁文平)

    2002-01-01

    The synthesis of a new series of asymmetric cationic gemini surfactant and the investigation of their miccellization behaviors by electronic spin resonance (ESR) as well as the surface tension measurements were reported. 4-Oxo-2,2,6,6-tetramethylpiperidine-N-oxyl (4-oxo-TEMPO) is used as the spin probe. The surfactants studied have the general formula [CnH2n+1 N+(CH3)2C6H12N+(CH3)2Cm H2m,1]Br2- , referred to as dimeric n-6-m surfactants, in which n and m are the numbers of carbon atoms in the asymmetric side alkyl chains. From the experimental data, rotational correlation time τc, surface tension and critical micelle concentration (cac) ,values, the physical properties of these new surfactants have preliminarily been evaluated. It is shown that this new series of asymmetric gmini surfactants has interesting micellization behaviors, and they are very different in aggregating tendency from their asymmetric analogues.

  16. Discrimination of radiation quality through second harmonic out-of-phase cw-ESR detection.

    Science.gov (United States)

    Marrale, Maurizio; Longo, Anna; Brai, Maria; Barbon, Antonio; Brustolon, Marina

    2014-02-01

    The ability to discriminate the quality of ionizing radiation is important because the biological effects produced in tissue strongly depends on both absorbed dose and linear energy transfer (LET) of ionizing particles. Here we present an experimental electron spin resonance (ESR) analysis aimed at discriminating the effective LETs of various radiation beams (e.g., 19.3 MeV protons, (60)Co photons and thermal neutrons). The measurement of the intensities of the continuous wave spectrometer signal channel first harmonic in-phase and the second harmonic out-of-phase components are used to distinguish the radiation quality. A computational analysis, was carried out to evaluate the dependence of the first harmonic in-phase and second harmonic out-of-phase components on microwave power, modulation amplitude and relaxation times, and highlights that these components could be used to point out differences in the relaxation times. On the basis of this numerical analysis the experimental results are discussed. The methodology described in this study has the potential to provide information on radiation quality. PMID:24524346

  17. Electrochemical and UV-Vis/ESR spectroelectrochemical properties of thienylenevinylenes substituted by a 4-cyanostyryl group

    Energy Technology Data Exchange (ETDEWEB)

    Czichy, M., E-mail: Malgorzata.Czichy@polsl.p [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Stolarczyk, A. [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Wagner, P. [Intelligent Polymer Research Institute and ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia); Domagala, W. [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Lapkowski, M. [Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 ks. M. Strzody Str., 44-100 Gliwice (Poland); Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Sklodowska-Curie Str., 41-819 Zabrze (Poland); Officer, D.L. [Intelligent Polymer Research Institute and ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia)

    2011-04-30

    Highlights: {yields} Electropolymerisation of the cyanostyryl substituted thienylenevinylene derivative affords a polymer having an optical band gap of ca. 1.8 eV, supplemented by soluble oligomers. {yields} Vinyl bonds of the thienylenevinylene derivative were found unstable upon electrooxidation of the molecule to a radical cation. {yields} Two groups of spins of the radical cation of the thienylenevinylene derivative have been identified. - Abstract: The {pi}-electron delocalisation in conjugated thienylenevinylenes bearing arylethenyl chromophores, makes those materials interesting candidates for electro-optic applications. In this study, we report the results of electrochemical and UV-Vis/ESR spectroelectrochemical studies of a pair of thienylenevinylenes substituted by the 4-cyanostyryl group, bearing either a hydrogen, or methyl group terminated {alpha} carbons at the peripheral thiophene rings. The reactivity of various functional segments of investigated molecules was assessed by comparing the reactivity of the protected and unprotected counterparts and the behaviour of their electrooxidation products. For the capped derivative, two irreversible anodic redox processes giving electrochemically inactive products were observed, while the uncapped molecule yields electroactive materials already upon its first oxidation step.

  18. Nuclear structure and reaction studies with exotic nuclei at the FRS-ESR

    International Nuclear Information System (INIS)

    Nuclear physics with exotic nuclei in storage rings was pioneered at the SIS-ESR facility in combination with the fragment separator FRS. Already the first experiments in the early 1990's gave access to ground-state properties like masses and half-lives and indicated the research potential of this novel instrumental approach. Many new data have been obtained and interesting phenomena have been explored, e.g. the mass surface was mapped over large areas of the chart of nuclei, isomer studies of long-lived states (with half-lives of the order minutes) became possible, the modification of decay properties for highly-charged, high-Z exotic nuclei was observed, and new decay modes, like the beta-decay to bound final states, were studied for the first time. A few years ago, direct reaction experiments on internal targets using inverse kinematics were started: transfer and pickup reactions of astrophysical interest were performed with stable isotopes at energies approaching the Gamow-window, while elastic and inelastic scattering experiments were performed with secondary beams of the unstable doubly magic isotope 56Ni quite recently. In this contribution, the achievements will be reviewed and recent results will be presented. It is dedicated to Paul Kienle. (authors)

  19. ESR evidence for radical production from the reaction of ozone with unsaturated lipids

    Energy Technology Data Exchange (ETDEWEB)

    Church, D.F.; McAdams, M.L..; Pryor, W.A. (Louisiana State Univ., Baton Rouge, (United States))

    1991-03-15

    The authors report electron spin resonance (ESR) spin trapping evidence for radical production by the reaction of ozone with unsaturated compounds. Soy and egg phosphatidylcholine liposomes, fatty acid emulsions, and homogeneous aqueous solutions of 3-hexenoic acid were treated with ozone in the presence of the spin trap {alpha}-phenyl-N-tert-butyl nitrone (PBN). Under these conditions, they observe spin adducts resulting from the trapping of both organic carbon- and oxygen-centered radicals. When the lipid-soluble antioxidant alpha-tocopherol is included in the liposomal systems, the formation of spin adducts is completely inhibited. The authors suggest that radicals giving rise to these spin adducts arise form the rapid decomposition of the 1,2,3-trioxolane intermediate that is initially formed when ozone reacts with the carbon-carbon double bonds of the substrates. These free radicals are not formed by the decomposition of the Criegee ozonide, since little of the ozonide is formed in the presence of water. Although hydrogen peroxide is the predominate peroxidic product of the ozone/alkene reaction, its decomposition is not responsible for the observed radical production since neither catalase nor iron chelators significantly affect the spin adduct yield. The radical yield is approximately 1%. Since a polyunsaturated fatty acid (PUFA) such as linoleic acid produces much higher concentrations of spin trappable radicals than does the monounsaturated fatty oleic acid, the results also suggest that sites in the lung containing higher levels of PUFA may be an important target for radical formation.

  20. ESR dosimetry in calibration intercomparisons with high-energy photons and electrons

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, K.J. (University Hospital of Copenhagen, Herlev (Denmark)); Hansen, J.W. (Risoe National Lab., Roskilde (Denmark)); Waligorski, M.P.R. (Institute of Nuclear Physics, Cracow (Poland))

    1989-01-01

    When alanine is exposed to radiation, stable free radicals are produced which may be measured by electron spin resonance (ESR) spectroscopy. Our dosimeters consist of L-{alpha}-alanine mixed with 5% polyvinyl pyrrolidone, compacted in the shape of 2-mm thick cylinders of 4.5 mm diameter. The alanine dosimeters were exposed to 0.25 to 16-MV {sub p} X-ray beams and 6 to 20-MeV electron beams and measured at Riso National Laboratory. Doses were determined by comparison with alanine dosimeters exposed to {sup 60}Co {gamma}-rays calibrated with Fricke dosimetry. At absorbed doses above 10 Gy, the standard deviation for the dose measurements was 1%. Dosimetry comparisons better than 2% at the 95% confidence level are possible. The dosimeters are easy to handle, robust and cheap, and may be read repeatedly. Fading after 100 Gy of {sup 60}Co {gamma}-rays and Linac-produced X-ray and electron beams is less than 2 and 6% in 4 years, respectively. Alanine dosimeters are useful for dosimetry comparisons both for photons and electrons, and the negligible fading make them ideal for documentation of patient doses in radiation therapy. (author).

  1. ESR Experiments on a Single Donor Electron in Isotopically Enriched Silicon

    Science.gov (United States)

    Tracy, Lisa; Luhman, Dwight; Carr, Stephen; Borchardt, John; Bishop, Nathaniel; Ten Eyck, Gregory; Pluym, Tammy; Wendt, Joel; Witzel, Wayne; Blume-Kohout, Robin; Nielsen, Erik; Lilly, Michael; Carroll, Malcolm

    In this talk we will discuss electron spin resonance experiments in single donor silicon qubit devices fabricated at Sandia National Labs. A self-aligned device structure consisting of a polysilicon gate SET located adjacent to the donor is used for donor electron spin readout. Using a cryogenic HEMT amplifier next to the silicon device, we demonstrate spin readout at 100 kHz bandwidth and Rabi oscillations with 0.96 visibility. Electron spin resonance measurements on these devices show a linewidth of 30 kHz and coherence times T2* = 10 us and T2 = 0.3 ms. We also discuss estimates of the fidelity of our donor electron spin qubit measurements using gate set tomography. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. ESR Experiments on a Single Donor Electron in Isotopically Enriched Silicon.

  2. Nuclear structure and reaction studies with exotic nuclei at the FRS-ESR

    Directory of Open Access Journals (Sweden)

    Scheidenberger Christoph

    2014-03-01

    Full Text Available Nuclear physics with exotic nuclei in storage rings was pioneered at the SIS-ESR facility in combination with the fragment separator FRS. Already the first experiments in the early 1990s gave access to ground-state properties like masses and half-lives and indicated the research potential of this novel instrumental approach. Many new data have been obtained and interesting phenomena have been explored, e.g. the mass surface was mapped over large areas of the chart of nuclei, isomer studies of long-lived states (with half-lives of the order minutes became possible, the modification of decay properties for highly-charged, high-Z exotic nuclei was observed, and new decay modes, like the beta-decay to bound final states, were studied for the first time. A few years ago, direct reaction experiments on internal targets using inverse kinematics were started: transfer and pickup reactions of astrophysical interest were performed with stable isotopes at energies approaching the Gamow-window, while elastic and inelastic scattering experiments were performed with secondary beams of the unstable doubly magic isotope 56Ni quite recently. In this contribution, the achievements will be reviewed and recent results will be presented. It is dedicated to Paul Kienle.

  3. An ESR study of the gamma radiolysis of aromatic polyesters containing isomeric naphthalene links

    Science.gov (United States)

    Hill, David J. T.; Choi, Bong-Ku; Ahn, Hung-Kun; Choi, E.-Joon

    2001-07-01

    Six polyesters were synthesised from 4,4'-oxy-bis(benzoyl chloride) and 1,4-, 1,5-, 1,6-, 2,3-, 2,6-, and 2,7-naphthalenediol isomers. The structures of the polyesters were characterised by means of IR, inherent viscosities in tetrachloroethane (TCE), solutions at 303 K and thermal analysis. The glass transition temperatures were in the range of 425-494 K by DSC thermal analysis. All of the polyesters were irradiated in an AECL Gammacell 220 unit at a dose rate of approximately 6.7 kGy/h to doses in the range of 0-15 kGy at 77 and 300 K. ESR spectroscopy was used to examine the radicals formed during radiolysis and to measure their yields. The G-values for radical formation in the polyesters were found to be in the range 0.18-1.41 at 77 K and 0.19-0.78 at 300 K. At 77 K, up to 15% of the radicals formed on radiolysis were found to be photo-bleachable anion radicals. Annealing experiments were carried out in order to identify the neutral radicals, which were assigned to naphthyl- or phenyl- and phenoxyl-type radicals.

  4. Polimorfismo de los genes receptores de estrogenos (ESR) y prolactina (PRLR) y su asociación con prolificidad y productividad de la cerda

    OpenAIRE

    Barreras Serrano, Alberto

    2012-01-01

    Los genes receptor de estrógeno (ESR) y receptor de prolactina (PRLR) fueron investigados como genes candidatos para características reproductivas. Dos localidades fueron incluidas en este estudio: Mexicali, Baja California y Navojoa, Sonora. Los genotipos para los genes ESR y PRLR fueron obtenidos de muestras sanguíneas de 136 hembras del sitio 1 (Baja California) y 300 provenientes del sitio 2 (Sonora). Los grupos genéticos utilizados fueron Yorkshire (Y), Landrace (...

  5. ESR and X-ray diffraction studies on thin films of poly-3-hexylthiophene: Molecular orientation and magnetic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, Keisuke [Material Science and Engeneering, Muroran Institute of Technology, 27-1 Mizomoto, Muroran, 050-8585 (Japan); Kojima, Takashi; Fukuda, Hisashi [Electrical and Electronic Engineering, Muroran Institute of Technology, 27-1 Mizomoto, Muroran, 050-8585 (Japan); Yashiro, Hisashi [Application Laboratory, Rigaku Corporation, 3-9-12 Akishima, Tokyo 196-8666 (Japan); Matsuura, Toshihiko [Laboratory of Biotechnology, Hokkaido University of Education, 1-2 Hachiman, Hakodate 040-8567 (Japan); Shimoyama, Yuhei [Material Science and Engeneering, Muroran Institute of Technology, 27-1 Mizomoto, Muroran, 050-8585 (Japan)], E-mail: simoyama@mmm.muroran-it.ac.jp

    2008-03-03

    Poly-3-hexylthiophene (P3HT) thin films were investigated by X-ray diffraction (XRD) and electron spin resonance (ESR) to reveal the film structure and molecular organization. The XRD data showed a diffraction pattern with a plane separation between the planes containing thiophene rings of 16.0 A. Comparison between the XRD patterns of powder and thin films of P3HT suggests that the main chains are folded on the substrate. Angular variation of the line position (g-value) of ESR spectra revealed that thiophene ring of P3HT orients along the substrate normal axis. The ESR linewidth varied by the angular rotation, indicating the one-dimensional spin-chain interactions in the P3HT thin films with a linear network of spin-chains. An organic thin-film transistor (OTFT) with P3HT film as a channel layer was then demonstrated. The P3HT films showed conducting characteristics with holes as carriers. The OTFTs indicated a field-effect mobility of 4.93 x 10{sup -3} cm{sup 2}/Vs and an on/off ratio of 73 in the accumulation mode.

  6. Evaluation of absorbed dose in irradiated sugar-containing plant material (peony roots) by an ESR method

    Science.gov (United States)

    Yamaoki, Rumi; Kimura, Shojiro; Ohta, Masatoshi

    2015-12-01

    The relationship between electron spin resonance (ESR) signal intensity of irradiated plant materials and sugar content was investigated by spectral analysis using peony roots. A weak background signal near g=2.005 was observed in the roots. After a 10 kGy irradiation, the ESR line broadened and the intensity increased, and the spectral characteristics were similar to a typical spectrum of irradiated food containing crystalline sugars. The free radical concentration was nearly stable 30 days after irradiation. The spectrum of peony root 30 days after irradiation was simulated using the summation of the intensities of six assumed components: radical signals derived from (a) sucrose, (b) glucose, (c) fructose, (d) cellulose, (e) the background signal near g=2.005 and (f) unidentified component. The simulated spectra using the six components were in agreement with the observed sample spectra. The intensity of sucrose radical signal in irradiated samples increased proportionally up to 20 kGy. In addition, the intensity of sucrose radical signals was strongly correlated with the sucrose contents of the samples. The results showed that the radiation sensitivity of sucrose in peony roots was influenced little by other plant constituents. There was also a good correlation between the total area of the spectra and the sucrose content, because the sucrose content was higher than that of other sugars in the samples. In peony roots, estimation of the absorbed dose from the ESR signal intensity may be possible by a calibration method based on the sucrose content.

  7. ESR studies on the thermal decomposition of trimethylamine oxide to formaldehyde and dimethylamine in jumbo squid (Dosidicus gigas) extract.

    Science.gov (United States)

    Zhu, Junli; Jia, Jia; Li, Xuepeng; Dong, Liangliang; Li, Jianrong

    2013-12-15

    The effects of ferrous iron, heating temperature and different additives on the decomposition of trimethylamine oxide (TMAO) to formaldehyde (FA) and dimethylamine (DMA) and generation of free radicals in jumbo squid (Dosidicus gigas) extract during heating were evaluated by electron spin resonance (ESR). The thermal decomposition of TMAO to TMA, DMA and FA and free radical signals was observed in squid extract, whereas no DMA, FA and free radical signals were detected in cod extract or in aqueous TMAO solution in vitro at high temperatures. Significant increase in levels of DMA, FA and radicals intensity were observed in squid extract and TMAO solution in the presence of ferrous iron with increasing temperature. Hydrogen peroxide stimulated the production of DMA, FA and ESR signals in squid extract, while citric acid, trisodium citrate, calcium chloride, tea polyphenols and resveratrol had the opposite effect. Similar ESR spectra of six peaks regarded as amminium radical were detected in the squid extract and TMAO-iron(II) solution, suggesting that the amminium radical was involved in the decomposition of TMAO. PMID:23993561

  8. Permeability studies of redox-sensitive nitroxyl spin probes in corn oil using an L-band ESR spectrometer

    Science.gov (United States)

    Jebaraj, D. David; Utsumi, Hideo; Asath, R. Mohamed; Benial, A. Milton Franklin

    2016-05-01

    Electron spin resonance (ESR) studies were carried out for 2mM 14N labeled 2H enriched 3-methoxycarbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl (MC-PROXYL) and 3-carboxy-2,2,5,5,-tetramethyl-1-pyrrolidinyloxy (carboxy-PROXYL) in pure water and various concentrations of corn oil. The ESR parameters, such as the line width, hyperfine coupling constant, g-factor, rotational correlation time, partition parameter and permeability were reported for the samples. The line width broadening was observed for both nitroxyl radicals in corn oil solutions. The partition parameter for permeable MC-PROXYL in corn oil increases with increasing concentration of corn oil, which reveals that the nitroxyl spin probe permeates into the oil phase. From the results, the corn oil concentration was optimized as 50 % for phantom studies. The rotational correlation time also increases with increasing concentration of corn oil. The permeable and impermeable nature of nitroxyl spin probes was demonstrated. These results will be useful for the development of ESR/OMR imaging modalities in in vivo and in vitro studies.

  9. The influence of the mould cooling temperature on the surface appearance and the internal quality of ESR ingots

    Science.gov (United States)

    Kubin, M.; Ofner, B.; Holzgruber, H.; Schneider, R.; Enzenhofer, D.; Filzwieser, A.; Konetschnik, S.

    2016-07-01

    One of the main benefits of the ESR process is to obtain an ingot surface which is smooth and allows a subsequent forging operation without any surface dressing. The main influencing factor on surface quality is the precise controlling of the process such as melt rate and electrode immersion depth. However, the relatively strong cooling effect of water as a cooling medium can result in the solidification of the meniscus of the liquid steel on the boundary liquid steel and slag which is most likely the origin of surface defects. The usage of different cooling media like ionic liquids, a salt solution which can be heated up to 250°C operating temperature might diminish the meniscus solidification phenomenon. This paper shows the first results of the usage of an ionic liquid as a mould cooling medium. In doing so, 210mm diameter ESR ingots were produced with the laboratory scale ESR furnace at the university of applied science using an ionic liquid cooling device developed by the company METTOP. For each trial melt different inlet and outlet temperatures of the ionic liquid were chosen and the impact on the surface appearance and internal quality were analyzed. Furthermore the influence on the energy balance is also briefly highlighted. Ultimately, an effect of the usage of ionic liquids as a cooling medium could be determined and these results will be described in detail within the scope of this paper.

  10. Acoustic emission source modeling

    Directory of Open Access Journals (Sweden)

    Hora P.

    2010-07-01

    Full Text Available The paper deals with the acoustic emission (AE source modeling by means of FEM system COMSOL Multiphysics. The following types of sources are used: the spatially concentrated force and the double forces (dipole. The pulse excitation is studied in both cases. As a material is used steel. The computed displacements are compared with the exact analytical solution of point sources under consideration.

  11. The acoustics of snoring.

    Science.gov (United States)

    Pevernagie, Dirk; Aarts, Ronald M; De Meyer, Micheline

    2010-04-01

    Snoring is a prevalent disorder affecting 20-40% of the general population. The mechanism of snoring is vibration of anatomical structures in the pharyngeal airway. Flutter of the soft palate accounts for the harsh aspect of the snoring sound. Natural or drug-induced sleep is required for its appearance. Snoring is subject to many influences such as body position, sleep stage, route of breathing and the presence or absence of sleep-disordered breathing. Its presentation may be variable within or between nights. While snoring is generally perceived as a social nuisance, rating of its noisiness is subjective and, therefore, inconsistent. Objective assessment of snoring is important to evaluate the effect of treatment interventions. Moreover, snoring carries information relating to the site and degree of obstruction of the upper airway. If evidence for monolevel snoring at the site of the soft palate is provided, the patient may benefit from palatal surgery. These considerations have inspired researchers to scrutinize the acoustic characteristics of snoring events. Similarly to speech, snoring is produced in the vocal tract. Because of this analogy, existing techniques for speech analysis have been applied to evaluate snoring sounds. It appears that the pitch of the snoring sound is in the low-frequency range (noise-like', and has scattered energy content in the higher spectral sub-bands (>500 Hz). To evaluate acoustic properties of snoring, sleep nasendoscopy is often performed. Recent evidence suggests that the acoustic quality of snoring is markedly different in drug-induced sleep as compared with natural sleep. Most often, palatal surgery alters sound characteristics of snoring, but is no cure for this disorder. It is uncertain whether the perceived improvement after palatal surgery, as judged by the bed partner, is due to an altered sound spectrum. Whether some acoustic aspects of snoring, such as changes in pitch, have predictive value for the presence of

  12. Acoustically enhanced heat transport

    Energy Technology Data Exchange (ETDEWEB)

    Ang, Kar M.; Hung, Yew Mun; Tan, Ming K., E-mail: tan.ming.kwang@monash.edu [School of Engineering, Monash University Malaysia, 47500 Bandar Sunway, Selangor (Malaysia); Yeo, Leslie Y. [Micro/Nanophysics Research Laboratory, RMIT University, Melbourne, VIC 3001 (Australia); Friend, James R. [Department of Mechanical and Aerospace Engineering, University of California, San Diego, California 92093 (United States)

    2016-01-15

    We investigate the enhancement of heat transfer in the nucleate boiling regime by inducing high frequency acoustic waves (f ∼ 10{sup 6} Hz) on the heated surface. In the experiments, liquid droplets (deionized water) are dispensed directly onto a heated, vibrating substrate. At lower vibration amplitudes (ξ{sub s} ∼ 10{sup −9} m), the improved heat transfer is mainly due to the detachment of vapor bubbles from the heated surface and the induced thermal mixing. Upon increasing the vibration amplitude (ξ{sub s} ∼ 10{sup −8} m), the heat transfer becomes more substantial due to the rapid bursting of vapor bubbles happening at the liquid-air interface as a consequence of capillary waves travelling in the thin liquid film between the vapor bubble and the air. Further increases then lead to rapid atomization that continues to enhance the heat transfer. An acoustic wave displacement amplitude on the order of 10{sup −8} m with 10{sup 6} Hz order frequencies is observed to produce an improvement of up to 50% reduction in the surface temperature over the case without acoustic excitation.

  13. Acoustics, computers and measurements

    Science.gov (United States)

    Truchard, James J.

    2003-10-01

    The human ear has created a high standard for the requirements of acoustical measurements. The transient nature of most acoustical signals has limited the success of traditional volt meters. Professor Hixson's pioneering work in electroacoustical measurements at ARL and The University of Texas helped set the stage for modern computer-based measurements. The tremendous performance of modern PCs and extensive libraries of signal processing functions in virtual instrumentation application software has revolutionized the way acoustical measurements are made. Today's analog to digital converters have up to 24 bits of resolution with a dynamic range of over 120 dB and a single PC processor can process 112 channels of FFTs at 4 kHz in real time. Wavelet technology further extends the capabilities for analyzing transients. The tools available for measurements in speech, electroacoustics, noise, and vibration represent some of the most advanced measurement tools available. During the last 50 years, Professor Hixson has helped drive this revolution from simple oscilloscope measurements to the modern high performance computer-based measurements.

  14. Fundamentals of Shallow Water Acoustics

    CERN Document Server

    Katsnelson, Boris; Lynch, James

    2012-01-01

    Shallow water acoustics (SWA), the study of how low and medium frequency sound propagates and scatters on the continental shelves of the world's oceans, has both technical interest and a large number of practical applications. Technically, shallow water poses an interesting medium for the study of acoustic scattering, inverse theory, and propagation physics in a complicated oceanic waveguide. Practically, shallow water acoustics has interest for geophysical exploration, marine mammal studies, and naval applications. Additionally, one notes the very interdisciplinary nature of shallow water acoustics, including acoustical physics, physical oceanography, marine geology, and marine biology. In this specialized volume, the authors, all of whom have extensive at-sea experience in U.S. and Russian research efforts, have tried to summarize the main experimental, theoretical, and computational results in shallow water acoustics, with an emphasis on providing physical insight into the topics presented.

  15. Latest Trends in Acoustic Sensing

    Directory of Open Access Journals (Sweden)

    Cinzia Caliendo

    2014-03-01

    Full Text Available Acoustics-based methods offer a powerful tool for sensing applications. Acoustic sensors can be applied in many fields ranging from materials characterization, structural health monitoring, acoustic imaging, defect characterization, etc., to name just a few. A proper selection of the acoustic wave frequency over a wide spectrum that extends from infrasound (<20 Hz up to ultrasound (in the GHz–band, together with a number of different propagating modes, including bulk longitudinal and shear waves, surface waves, plate modes, etc., allow acoustic tools to be successfully applied to the characterization of gaseous, solid and liquid environments. The purpose of this special issue is to provide an overview of the research trends in acoustic wave sensing through some cases that are representative of specific applications in different sensing fields.

  16. High-Frequency Seafloor Acoustics

    CERN Document Server

    Jackson, Darrell R

    2007-01-01

    High-Frequency Seafloor Acoustics is the first book in a new series sponsored by the Office of Naval Research on the latest research in underwater acoustics. This exciting new title provides ready access to experimental data, theory, and models relevant to high-frequency seafloor acoustics and will be of interest to sonar engineers and researchers working in underwater acoustics. The physical characteristics of the seafloor affecting acoustic propagation and scattering are covered, including physical and geoacoustic properties and surface roughness. Current theories for acoustic propagation in sediments are presented along with corresponding models for reflection, scattering, and seafloor penetration. The main text is backed up by an extensive bibliography and technical appendices.

  17. Acoustical coupling of lizard eardrums

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, Jakob; Manley, Geoffrey A

    2008-01-01

    Lizard ears are clear examples of two-input pressure-difference receivers, with up to 40-dB differences in eardrum vibration amplitude in response to ipsi- and contralateral stimulus directions. The directionality is created by acoustical coupling of the eardrums and interaction of the direct...... is caused by the acoustic interaction of the two eardrums. The results can be largely explained by a simple acoustical model based on an electrical analog circuit....

  18. Room acoustic auralization with Ambisonics

    OpenAIRE

    Polack, Jean-Dominique; Leão Figueiredo, Fábio

    2012-01-01

    International audience During the year of 2009, the room acoustics group of the LAM (Équipe Lutheries, Acoustique, Musique de l’Institut Jean Le Rond d’Alembert - Université Pierre et Marie Curie, Paris) performed a series of acoustical measurements in music halls in Paris. The halls were chosen in regarding their importance to the historic, architectural or acoustic domains. The measured ensemble of fourteen rooms includes quite different architectural designs. The measurements were carri...

  19. Combined Environment Acoustic Chamber (CEAC)

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The CEAC imposes combined acoustic, thermal and mechanical loads on aerospace structures. The CEAC is employed to measure structural response and determine...

  20. Incidence and clinical significance of ESR1 mutations in heavily pretreated metastatic breast cancer patients

    Directory of Open Access Journals (Sweden)

    Niu J

    2015-11-01

    Full Text Available Jiaxin Niu,1 Grant Andres,1 Kim Kramer,2 Madappa N Kundranda,3 Ricardo H Alvarez,4 Eiko Klimant,5 Ankur R Parikh,5 Bradford Tan,6 Edgar D Staren,7 Maurie Markman8 1Department of Medical Oncology, Western Regional Medical Center at Cancer Treatment Centers of America (CTCA, Goodyear, AZ, USA; 2CTCA Medicine and Science, Zion, IL, USA; 3Department of Medical Oncology, Banner MD Anderson Cancer Center, Gilbert, AZ, USA; 4Department of Medical Oncology, Southeastern Regional Medical Center at CTCA, Newnan, GA, USA; 5Department of Medical Oncology, Eastern Regional Medical Center at CTCA, Philadelphia, PA, USA; 6Department of Pathology, Midwestern Regional Medical Center at CTCA, Zion, IL, USA; 7Advanced Individual Medicine, Phoenix, AZ, USA; 8CTCA Medicine and Science, Philadelphia, PA, USA Background: ESR1 mutation has recently emerged as one of the important mechanisms involved in endocrine resistance. The incidence and clinical implication of ESR1 mutation has not been well evaluated in heavily pretreated breast cancer patients. Methods: We conducted a retrospective review of advanced breast cancer patients with tumors who underwent next-generation sequencing genomic profiling using Foundation One test at Cancer Treatment Centers of America® regional hospitals between November 2012 and November 2014. Results: We identified a total of 341 patients including 217 (59% estrogen receptor (ER+, 177 (48% progesterone receptor (PR+, 30 (8% hormone receptor+/HER2 positive, and 119 (32% triple negative patients. ESR1 mutation was noted in 27/222 (12.1% ER+ or PR+ breast cancer patients. All ER+ patients received at least one line of an aromatase inhibitor. All 28 patients were found to harbor ESR1 mutations affecting ligand-binding domain with the most common mutations affecting Y537 (17/28, 60.7% and D538 (9/28, 32.1%. In this cohort, 19 (67.9% patients carried three or more, seven (25% patients had one or two additional genomic alterations and one (3

  1. Acoustic transparency and slow sound using detuned acoustic resonators

    DEFF Research Database (Denmark)

    Santillan, Arturo Orozco; Bozhevolnyi, Sergey I.

    2011-01-01

    We demonstrate that the phenomenon of acoustic transparency and slowsound propagation can be realized with detuned acoustic resonators (DAR), mimicking thereby the effect of electromagnetically induced transparency (EIT) in atomic physics. Sound propagation in a pipe with a series of side...

  2. Decomposition of beta-ray induced ESR spectra of fossil tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Joannes-Boyau, Renaud, E-mail: renaud.joannes-boyau@anu.edu.a [Research School of Earth Sciences, Australian National University, Canberra, ACT 0200 (Australia); Gruen, Rainer [Research School of Earth Sciences, Australian National University, Canberra, ACT 0200 (Australia)

    2011-03-15

    Two fossil tooth enamel fragments were irradiated with beta rays, one through the outer surface, the other through the dentine-enamel junction. The angular ESR spectra of the two fragments were decomposed using an automated simulated annealing (SA) procedure, which is particularly well suited to separate overlapping signals. Beta irradiation generated different qualitative and quantitative responses to previous gamma irradiation experiments. Similar to gamma rays, the beta irradiation created both non-oriented and oriented CO{sub 2}{sup -} radicals. In contrast to gamma irradiation, which only created orthorhombic oriented CO{sub 2}{sup -} radicals, both axial and orthorhombic CO{sub 2}{sup -} radicals were extracted after beta irradiation. Furthermore, gamma irradiation created significantly more non-oriented radicals than beta irradiation. Altogether, the radical distribution created by beta irradiation resembled that of the natural sample, which had been exposed to environmental irradiation over several hundreds of thousands of years. The natural sample contained 9% non-orientated CO{sub 2}{sup -} radicals and a mix of orthorhombic to axial CO{sub 2}{sup -} radicals in the ratio of 35:65. The beta induced spectra of the fragment irradiated through the outer surface contained 9% non-orientated CO{sub 2}{sup -} radicals and a mix of orthorhombic to axial CO{sub 2}{sup -} radicals in the ratio of 45:55, while for the other sample these values were 19% and 59:41, respectively. The angle between the axial and orthorhombic CO{sub 2}{sup -} radicals is around 23{sup o} in both natural and beta irradiation components. This indicates that the radicals produced by the different irradiation modes are located in the same positions in the hydroxyapatite crystals. The higher percentage of non-oriented CO{sub 2}{sup -} radicals closer to the dentine-enamel junction points to interprismatic zones for their possible location.

  3. Glacial advances and ESR chronology of the Pochengzi Glaciation,Tianshan Mountains,China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The Pochengzi Glaciation is a typical glaciation in Quaternary in the Tianshan Mountains. The glacial landforms comprise several integrated end moraines, like a fan spreading from the north to the south at the mouth of the Muzhaerte River valley and on the piedmont on the southeastern slope of the Tumur Peak, the largest center of modern glaciation in the Tianshan Mountains. The landforms recorded a complex history of the ancient glacier change and contained considerable information of the glacial landscape evolution, and dating these landforms helps us understand the temporal and spatial shifts of the past cryosphere in this valley and reconstruct the paleoenvironment in this region. Electron spin resonance (ESR) dating of the glacial tills in the upper stratum from a well-exposed section, end moraines, and associated outwashes was carried out using Ge centers in quartz grains, which are sensitive to the sunlight and grinding. The results could be divided into three clusters, 13.6–25.3, 39.5–40.4 and 64.2–71.7 ka. Based on the principle of geomorphology and stratigraphy and the available paleoen- vironmental data from northwestern China, the end moraines were determined to deposit in the Last Glaciation. The landforms and the three clusters of ages demonstrate that at least three large glacial advances occurred during the Pochengzi Glaciation, which are corresponding to marine oxygen isotope stage 4 (MIS4), MIS3b and MIS2. The landforms also indicate that the gla- ciers were compound valley glacier in MIS2 and MIS3b and piedmont glacier in MIS4, and the ancient Muzhaerte glacier were 94, 95 and 99 km at their maximum extensions in these three glacial advances.

  4. ESR study of molecular orientation and dynamics of TEMPO derivatives in CLPOT 1D nanochannels.

    Science.gov (United States)

    Kobayashi, Hirokazu; Furuhashi, Yuta; Nakagawa, Haruka; Asaji, Tetsuo

    2016-08-01

    The molecular orientations and dynamics of 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) radical derivatives with large substituent groups at the 4-position (4-X-TEMPO) in the organic one-dimensional nanochannels within the nanosized molecular template 2,4,6-tris(4-chlorophenoxy)-1,3,5-triazine (CLPOT) were examined using ESR. The concentrations of guest radicals, including 4-methoxy-TEMPO (MeO-TEMPO) or 4-oxo-TEMPO (TEMPONE), in the CLPOT nanochannels in each inclusion compound (IC) were reduced by co-including 4-substituted-2,2,6,6-tetramethylpiperidine (4-R-TEMP) compounds at a ratio of 1 : 30-1 : 600. At higher temperatures, the guest radicals in each IC underwent anisotropic rotational diffusion in the CLPOT nanochannels. The rotational diffusion activation energy, Ea , associated with MeO-TEMPO or TEMPONE in the CLPOT nanochannels (6-7 kJ mol(-1) ), was independent of the size and type of substituent group and was similar to the Ea values obtained for TEMPO and 4- hydroxy-TEMPO (TEMPOL) in our previous study. However, in the case in which TEMP was used as a guest compound for dilution (spacer), the tilt of the rotational axis to the principal axis system of the g-tensor, and the rotational diffusion correlation time, τR , of each guest radical in the CLPOT nanochannels were different from the case with other 4-R-TEMP. These results indicate the possibility of controlling molecular orientation and dynamics of guest radicals in CLPOT ICs through the appropriate choice of spacer. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27001507

  5. Synthesis, structure and ESR studies of Mg doped ZnAlO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Cakiroglu, O. [Istanbul University, Hasan Ali Yucel Education Faculty, Beyazit, 34452 Istanbul (Turkey); Acikgoz, M. [Bahcesehir University, Faculty of Arts and Sciences, Department of Mathematics and Computer Sciences, Besiktas, 34349 Istanbul (Turkey); Arda, L., E-mail: lutfi.arda@bahcesehir.edu.tr [Bahcesehir University, Faculty of Arts and Sciences, Department of Mathematics and Computer Sciences, Besiktas, 34349 Istanbul (Turkey); Akcan, D. [Bahcesehir University, Faculty of Arts and Sciences, Department of Mathematics and Computer Sciences, Besiktas, 34349 Istanbul (Turkey); Dogan, N. [Gebze Institute of Technology, Department of Physics, 41400 Gebze/Kocaeli (Turkey)

    2015-01-01

    Zn{sub 0.98−x}Mg{sub x}Al{sub 0.02}O solutions with different (x=0.05, 0.10, 0.15, and 0.20) compositions were synthesized by the sol–gel technique using Zn, Mg and Al based alkoxide. The effects of highly Mg doping ratio on structure and magnetic properties were investigated systematically. The phase and the crystal structure of the Zn{sub 0.98−x}Mg{sub x}Al{sub 0.02}O nanoparticles were characterized using X-ray diffraction. Scanning Electron Microscope and X-ray diffraction were utilized to understand the size and microstructure of samples. We observed the particle sizes of nanoparticles between 80 nm and 100 nm range. Furthermore, ESR spectra of Zn{sub 0.98−x}Mg{sub x}Al{sub 0.02}O nanoparticles were collected at room temperature on a Bruker EMX model X-band spectrometer operating at a frequency of 9.50 GHz. It is observed that the critical concentration of Mg, x=0.1, has minimum g-factor and maximum line-width (W). - Highlights: • Zn{sub 0.98−x}Mg{sub x}Al{sub 0.02}O{sub ,} (0.05≤x≤0.20) nanoparticles were prepared by sol–gel technique. • The Mg concentration is increased, the agglomeration and malting of nanoparticles increase. • Rietveld analysis of ZnMgAlO shows single phase (ZnO) for x<0.2 concentration. • The critical concentration of Mg is x=0.1 to have minimum g-factor and maximum line-width W.

  6. Acoustic Mechanical Feedthroughs

    Science.gov (United States)

    Sherrit, Stewart; Walkemeyer, Phillip; Bao, Xiaoqi; Bar-Cohen, Yoseph; Badescu, Mircea

    2013-01-01

    Electromagnetic motors can have problems when operating in extreme environments. In addition, if one needs to do mechanical work outside a structure, electrical feedthroughs are required to transport the electric power to drive the motor. In this paper, we present designs for driving rotary and linear motors by pumping stress waves across a structure or barrier. We accomplish this by designing a piezoelectric actuator on one side of the structure and a resonance structure that is matched to the piezoelectric resonance of the actuator on the other side. Typically, piezoelectric motors can be designed with high torques and lower speeds without the need for gears. One can also use other actuation materials such as electrostrictive, or magnetostrictive materials in a benign environment and transmit the power in acoustic form as a stress wave and actuate mechanisms that are external to the benign environment. This technology removes the need to perforate a structure and allows work to be done directly on the other side of a structure without the use of electrical feedthroughs, which can weaken the structure, pipe, or vessel. Acoustic energy is pumped as a stress wave at a set frequency or range of frequencies to produce rotary or linear motion in a structure. This method of transferring useful mechanical work across solid barriers by pumping acoustic energy through a resonant structure features the ability to transfer work (rotary or linear motion) across pressure or thermal barriers, or in a sterile environment, without generating contaminants. Reflectors in the wall of barriers can be designed to enhance the efficiency of the energy/power transmission. The method features the ability to produce a bi-directional driving mechanism using higher-mode resonances. There are a variety of applications where the presence of a motor is complicated by thermal or chemical environments that would be hostile to the motor components and reduce life and, in some instances, not be

  7. Taming Acoustic Cavitation

    CERN Document Server

    Rivas, David Fernandez; Enriquez, Oscar R; Versluis, Michel; Prosperetti, Andrea; Gardeniers, Han; Lohse, Detlef

    2012-01-01

    In this fluid dynamics video we show acoustic cavitation occurring from pits etched on a silicon surface. By immersing the surface in a liquid, gas pockets are entrapped in the pits which upon ultrasonic insonation, are observed to shed cavitation bubbles. Modulating the driving pressure it is possible to induce different behaviours based on the force balance that determines the interaction among bubbles and the silicon surface. This system can be used for several applications like sonochemical water treatment, cleaning of surfaces with deposited materials such as biofilms.

  8. Lecture Notes On Acoustics

    International Nuclear Information System (INIS)

    This book mentions string vibration and wave, one-dimension wave and wave equation, characteristic impedance, governing equation of string, and wave energy from string, wave equation of wave and basic physical quantity like one-dimension wave equation, sound unit, sound intensity and energy, sound movement in a surface of discontinuity with transmission loss of sound by partition, and Snell's law, radiation, scatter and diffraction and sound in closed space with Sabine's theory, sound characteristic of closed space and duct acoustics.

  9. Dynamic acoustic tractor beams

    Energy Technology Data Exchange (ETDEWEB)

    Mitri, F. G., E-mail: F.G.Mitri@ieee.org [Chevron, Area 52 Technology – ETC, Santa Fe, New Mexico 87508 (United States)

    2015-03-07

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  10. Dynamic acoustic tractor beams

    Science.gov (United States)

    Mitri, F. G.

    2015-03-01

    Pulling a sphere and vibrating it around an equilibrium position by amplitude-modulation in the near-field of a single finite circular piston transducer is theoretically demonstrated. Conditions are found where a fluid hexane sphere (with arbitrary radius) chosen as an example, centered on the axis of progressive propagating waves and submerged in non-viscous water, experiences an attractive (steady) force pulling it towards the transducer, as well as an oscillatory force forcing it to vibrate back-and-forth. Numerical predictions for the dynamic force illustrate the theory and suggest an innovative method in designing dynamic acoustical tractor beams.

  11. Acoustic Similarity and Dichotic Listening.

    Science.gov (United States)

    Benson, Peter

    1978-01-01

    An experiment tests conjectures that right ear advantage (REA) has an auditory origin in competition or interference between acoustically similar stimuli and that feature-sharing effect (FSE) has its origin in assignment of features of phonetically similar stimuli. No effect on the REA for acoustic similarity, and a clear effect of acoustic…

  12. Acoustic Center or Time Origin?

    DEFF Research Database (Denmark)

    Staffeldt, Henrik

    1999-01-01

    The paper discusses the acoustic center in relation to measurements of loudspeaker polar data. Also, it presents the related concept time origin and discusses the deviation that appears between positions of the acoustic center found by wavefront based and time based measuring methods....

  13. Digital Controller For Acoustic Levitation

    Science.gov (United States)

    Tarver, D. Kent

    1989-01-01

    Acoustic driver digitally controls sound fields along three axes. Allows computerized acoustic levitation and manipulation of small objects for such purposes as containerless processing and nuclear-fusion power experiments. Also used for controlling motion of vibration-testing tables in three dimensions.

  14. Propagation of Ion Acoustic Perturbations

    DEFF Research Database (Denmark)

    Pécseli, Hans

    1975-01-01

    Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered.......Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered....

  15. Investigation of the isochronous mode of the experimental storage ring (ESR) and the collector ring (CR). Decay spectroscopy of highly charged stored {sup 140}Pr ions at the FRS-ESR facility

    Energy Technology Data Exchange (ETDEWEB)

    Litvinov, Sergey A.

    2008-11-15

    The combination of the present fragment separator FRS and the cooler-storage ring ESR at GSI provides conditions for accurate mass and unique half-life measurements of exotic nuclei. A major part of this doctoral work has been devoted to investigations of the isochronous ion-optical operating mode of the present ESR facility and the planned Collector Ring (CR) facility at FAIR. A detailed ion-optical study of the isochronous storage ring with the emphasis on the main parameters has been done. For example, a simple scaling law providing a quantitative estimate for the mass resolving power as a function of the transverse acceptance has been derived. The ion-optical matching of the FRS-ESR has been calculated and experimentally verified for both the standard and the isochronous operating modes of the ESR. In addition, the dispersion function of a stored ion beam has been measured for both ion-optical modes at the straight section. The improved setting for higher transmission in the standard mode has been used in an experiment on the half-life measurements of highly-charged ions. Orbital electron capture (EC) and/or {beta}{sup +}-decay rates of {sup 140}Pr ions with zero-, one- and two- bound electrons have been measured. A complementary future study of EC-decay in highly-charged {sup 64}Cu ions is discussed. Based on the present experience, the ion-optical matching between the future in-flight fragment separator Super-FRS and the CR has been calculated. The isochronous mode of the CR has been calculated. A dedicated Monte-Carlo code (ISOCHRON) has been developed in order to investigate the influence of the transverse acceptance, the closed orbit distortions, the fringe fields of the quadrupoles, the magnetic field imperfections of the magnets on the mass resolving power. The influence of chromaticity on the isochronicity has been investigated. The correction of the chromaticity and of second-order isochronicity has been performed employing sextupole magnets in the

  16. Investigation of the isochronous mode of the experimental storage ring (ESR) and the collector ring (CR). Decay spectroscopy of highly charged stored 140Pr ions at the FRS-ESR facility

    International Nuclear Information System (INIS)

    The combination of the present fragment separator FRS and the cooler-storage ring ESR at GSI provides conditions for accurate mass and unique half-life measurements of exotic nuclei. A major part of this doctoral work has been devoted to investigations of the isochronous ion-optical operating mode of the present ESR facility and the planned Collector Ring (CR) facility at FAIR. A detailed ion-optical study of the isochronous storage ring with the emphasis on the main parameters has been done. For example, a simple scaling law providing a quantitative estimate for the mass resolving power as a function of the transverse acceptance has been derived. The ion-optical matching of the FRS-ESR has been calculated and experimentally verified for both the standard and the isochronous operating modes of the ESR. In addition, the dispersion function of a stored ion beam has been measured for both ion-optical modes at the straight section. The improved setting for higher transmission in the standard mode has been used in an experiment on the half-life measurements of highly-charged ions. Orbital electron capture (EC) and/or β+-decay rates of 140Pr ions with zero-, one- and two- bound electrons have been measured. A complementary future study of EC-decay in highly-charged 64Cu ions is discussed. Based on the present experience, the ion-optical matching between the future in-flight fragment separator Super-FRS and the CR has been calculated. The isochronous mode of the CR has been calculated. A dedicated Monte-Carlo code (ISOCHRON) has been developed in order to investigate the influence of the transverse acceptance, the closed orbit distortions, the fringe fields of the quadrupoles, the magnetic field imperfections of the magnets on the mass resolving power. The influence of chromaticity on the isochronicity has been investigated. The correction of the chromaticity and of second-order isochronicity has been performed employing sextupole magnets in the arcs of the CR. The

  17. MEMS Based Acoustic Array

    Science.gov (United States)

    Sheplak, Mark (Inventor); Nishida, Toshikaza (Inventor); Humphreys, William M. (Inventor); Arnold, David P. (Inventor)

    2006-01-01

    Embodiments of the present invention described and shown in the specification aid drawings include a combination responsive to an acoustic wave that can be utilized as a dynamic pressure sensor. In one embodiment of the present invention, the combination has a substrate having a first surface and an opposite second surface, a microphone positioned on the first surface of the substrate and having an input and a first output and a second output, wherein the input receives a biased voltage, and the microphone generates an output signal responsive to the acoustic wave between the first output and the second output. The combination further has an amplifier positioned on the first surface of the substrate and having a first input and a second input and an output, wherein the first input of the amplifier is electrically coupled to the first output of the microphone and the second input of the amplifier is electrically coupled to the second output of the microphone for receiving the output sinual from the microphone. The amplifier is spaced from the microphone with a separation smaller than 0.5 mm.

  18. Acoustics and Hearing

    CERN Document Server

    Damaske, Peter

    2008-01-01

    When one listens to music at home, one would like to have an acoustic impression close to that of being in the concert hall. Until recently this meant elaborate multi-channelled sound systems with 5 or more speakers. But head-related stereophony achieves the surround-sound effect in living rooms with only two loudspeakers. By virtue of their slight directivity as well as an electronic filter the limitations previously common to two-speaker systems can be overcome and this holds for any arbitrary two-channel recording. The book also investigates the question of how a wide and diffuse sound image can arise in concert halls and shows that the quality of concert halls decisively depends on diffuse sound images arising in the onset of reverberation. For this purpose a strong onset of reverberation is modified in an anechoic chamber by electroacoustic means. Acoustics and Hearing proposes ideas concerning signal processing in the auditory system that explain the measured results and the resultant sound effects plea...

  19. Acoustic data transmission method

    Energy Technology Data Exchange (ETDEWEB)

    Duckworth, A.

    1991-09-17

    This patent describes a method for transmitting time line data through a drillstring having drill pipe sections connected end-to-end by joints from a first location below the surface of the earth to a second location at or near the surface of the earth, the length and cross-sectional area of the drill pipe sections being different from the length and cross-sectional area of the joints. It comprises generating acoustic data signals having a single frequency content in at least one passband of the drillstring; transmitting the data signals through the drillstring from either the first location to the second location or from the second location to the first location during a time period prior to the onset of reflective interference caused by the data signals reflecting from along the length of the drillstring, the time period being equal to or less than the time for the data signals to travel three lengths of the drillstring; stopping the transmission of data signals at the onset of the reflective interference and allowing the acoustic signals to substantially attenuate; and detecting the data signals at the respective first or second location.

  20. White paper of the European Association of Nuclear Medicine (EANM) and the European Society of Radiology (ESR) on multimodality imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bischof Delaloye, Angelika [Centre Hospitalier Universitaire Vaudois, Service de Medecine Nucleaire, Lausanne (Switzerland); Carrio, Ignasi [Hospital Sant Pau, Nuclear Medicine Department, Barcelona (Spain); Cuocolo, Alberto [University Federico II, Department of Biomorphological and Functional Sciences, Naples (Italy); Knapp, Wolfram [Medizinische Hochschule Hannover, Klinik fuer Nuklearmedizin, Hannover (Germany); Gourtsoyiannis, Nicholas [University Hospital of Iraklion, Department of Radiology, Iraklion (Greece); McCall, Iain [The Robert Jones and Agnes Hunt Orthopaedic and District Hospital NHS Trust, Department of Radiology, Oswestry, Shropshire (United Kingdom); Reiser, Maximilian [Institut fuer Radiologische Diagnostik, Klinikum Grosshadern/LMU, Munich (Germany); Silberman, Bruno [Imagerie Pais Centre, Paris (France)

    2007-08-15

    New multimodality imaging systems bring together anatomical and molecular information and require the competency and accreditation of individuals from both nuclear medicine and radiology. This paper sets out the positions and aspirations of the European Association of Nuclear Medicine (EANM) and the European Society of Radiology (ESR) working together on an equal and constructive basis for the future benefit of both specialties. EANM and ESR recognise the importance of coordinating working practices for multimodality imaging systems and that undertaking the nuclear medicine and radiology components of imaging with hybrid systems requires different skills. It is important to provide adequate and appropriate training in the two disciplines in order to offer a proper service to the patient using hybrid systems. Training models are proposed with the overall objective of providing opportunities for acquisition of special competency certification in multimodality imaging. Both organisations plan to develop common procedural guidelines and recognise the importance of coordinating the purchasing and management of hybrid systems to maximise the benefits to both specialties and to ensure appropriate reimbursement of these examinations. European multimodality imaging research is operating in a highly competitive environment. The coming years will decide whether European research in this area manages to defend its leading position or whether it falls behind research in other leading economies. Since research teams in the Member States are not always sufficiently interconnected, more European input is necessary to create interdisciplinary bridges between research institutions in Europe and to stimulate excellence. EANM and ESR will work with the European Institute for Biomedical Imaging Research (EIBIR) to develop further research opportunities across Europe. European Union grant-funding bodies should allocate funds to joint research initiatives that encompass clinical research

  1. White paper of the European Society of Radiology (ESR) and the European Association of Nuclear Medicine (EANM) on multimodality imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gourtsoyiannis, Nicholas [University Hospital of Iraklion, Department of Radiology, Iraklion (Greece); McCall, Iain [The Robert Jones and Agnes Hunt Orthopaedic and District Hospital NHS Trust, Department of Radiology, Oswestry, Shropshire (United Kingdom); Reiser, Maximilian [Klinikum Grosshadern/LMU, Institut fuer Radiologische Diagnostik, Munich (Germany); Silberman, Bruno [Imagerie Pais Centre, Paris (France); Bischof Delaloye, Angelika [Centre Hospitalier Universitaire Vaudois, Service de Medecine Nucleaire, Lausanne (Switzerland); Carrio, Ignacio [Hospital Sant Pau, Nuclear Medicine Department, Barcelona (Spain); Cuocolo, Alberto [University Federico II, Department of Biomorphological and Functional Sciences, Naples (Italy); Knapp, Wolfram [Medizinische Hochschule Hannover, Klinik fuer Nuklearmedizin, Hannover (Germany)

    2007-08-15

    New multimodality imaging systems bring together anatomical and molecular information and require the competency and accreditation of individuals from both radiology and nuclear medicine. This paper sets out the positions and aspirations of the European Society of Radiology (ESR) and the European Association of Nuclear Medicine (EANM) working together on an equal and constructive basis for the future benefit of both specialties. ESR and EANM recognise the importance of coordinating working practices for multimodality imaging systems and that undertaking the radiology and nuclear medicine components of imaging with hybrid systems requires different skills. It is important to provide adequate and appropriate training in the two disciplines in order to offer a proper service to the patient using hybrid systems. Training models are proposed with the overall objective of providing opportunities for acquisition of special competency certification in multimodality imaging. Both organisations plan to develop common procedural guidelines and recognise the importance of coordinating the purchasing and management of hybrid systems to maximise the benefits to both specialties and to ensure appropriate reimbursement of these examinations. European multimodality imaging research is operating in a highly competitive environment. The coming years will decide whether European research in this area manages to defend its leading position or whether it falls behind research in other leading economies. Since research teams in the member states are not always sufficiently interconnected, more European input is necessary to create interdisciplinary bridges between research institutions in Europe and to stimulate excellence. ESR and EANM will work with the European Institute for Biomedical Imaging Research (EIBIR) to develop further research opportunities across Europe. European Union grant-funding bodies should allocate funds to joint research initiatives that encompass clinical research

  2. The alpha effectiveness for formation of SO3- in barite: an essential factor for ESR dating of submarine hydrothermal barite

    Science.gov (United States)

    Isono, Y.; Toyoda, S.; Nishido, H.; Kayama, M.

    2013-12-01

    While Kasuya et al. (1991) first pointed out that ESR (electron spin resonance) dating of barite (BaSO4) is possible, the method was first practically applied by Okumura et al. (2010) to a sample formed by the submarine hydrothermal activity. A subsequent study by Sato et al. (2011) studied the thermal stability of the signal and concluded that the dating signal due to SO3- is stable so that dating method is applicable up to at least several thousand years. Barite crystals formed by submarine hydrothermal activities contains large amount of Ra which replaces Ba in the crystal lattice where all dose rate is due to radiation from Ra. Okumura et al. (2010) reported a concentration of 7.7 Bq/g of Ra in a hydrothermal sulfide including barite where the internal alpha dose rate in barite contributes 40 to 60 % of total dose rate. Determination of alpha effectiveness is thus the one of the essential factors for improving the precision of dating of barite by ESR. Toyoda et al. (2012) investigated the alpha effectiveness for the ESR signal due to SO3- in barite by comparing the dose responses of the signal for gamma irradiation and for He ion implantation with an energy of 4 MeV. A value 0.043 ×0.018 was obtained for a sample from Morocco. However, the dose response was far from 'good', where the number of points is not sufficient. The experiments of He ion implantation was repeated in the present study for several samples to determine the precise alpha effectiveness. A value of 0.019 ×0.0096 and 0.0062 ×0.0036 were obtained for the samples from Morocco and from Funaoka Mine, Japan, respectively. The results of further repeated analysis will be presented.

  3. An ESR study of the radiation chemistry of poly (tetrafluoroethylene-co-hexafluoropropylene) at 77 and 300 K

    Science.gov (United States)

    Hill, David J. T.; Mohajerani, Shahroo; Pomery, Peter J.; Whittaker, Andrew K.

    2000-09-01

    The effect of gamma-irradiation on poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) with a composition of ≈9:1 has been investigated at low doses by Electron Spin Resonance Spectroscopy (ESR). Irradiations have been carried out at 77 and 300 K and the spectra of the radical intermediates have been delineated and the temperature dependencies of the spectra of the major radicals present have been identified. The overall G-values for radical formation at 77 and 300 K were found to be 0.22 ± 0.1 and 2.0 ± 0.1, respectively.

  4. The power of thermal annealing of γ-irradiated Ultem in disclosing its radiation chemistry using ESR

    International Nuclear Information System (INIS)

    Full text: Ultem has previously been studied for irradiation using 60Co γ- rays at 77 K and then subsequently photobleached and annealed to higher temperatures. However the ESR spectra of thermal annealing were not well resolved which made the identification of the radicals rather difficult. In the present study this problem was overcome and some of the radicals stable at different temperatures were identified by measuring their g values and the hyper fine splitting constants. The difference spectra of Ultem obtained at different annealing temperature regions were characterised by triplet, singlets and six-line spectra. These signals were assigned to methylene, phenyl, phenoxy, and disubstituted benzyl radicals

  5. An ESR study of the radiation chemistry of poly (tetrafluoroethylene-co-hexafluoropropylene) at 77 and 300 K

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.J.T. E-mail: hill@chemistry.uq.edu.au; Mohajerani, Shahroo; Pomery, P.J.; Whittaker, A.K

    2000-09-01

    The effect of gamma-irradiation on poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) with a composition of {approx}9:1 has been investigated at low doses by Electron Spin Resonance Spectroscopy (ESR). Irradiations have been carried out at 77 and 300 K and the spectra of the radical intermediates have been delineated and the temperature dependencies of the spectra of the major radicals present have been identified. The overall G-values for radical formation at 77 and 300 K were found to be 0.22{+-}0.1 and 2.0{+-}0.1, respectively.

  6. An ESR study of the radiation chemistry of poly (tetrafluoroethylene-co-hexafluoropropylene) at 77 and 300 K

    International Nuclear Information System (INIS)

    The effect of gamma-irradiation on poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) with a composition of ∼9:1 has been investigated at low doses by Electron Spin Resonance Spectroscopy (ESR). Irradiations have been carried out at 77 and 300 K and the spectra of the radical intermediates have been delineated and the temperature dependencies of the spectra of the major radicals present have been identified. The overall G-values for radical formation at 77 and 300 K were found to be 0.22±0.1 and 2.0±0.1, respectively

  7. Co-trial on ESR identification and estimates of. gamma. -ray and electron absorbed doses given to meat and bones

    Energy Technology Data Exchange (ETDEWEB)

    Desrosiers, M.F.; McLaughlin, W.L.; Sheahen, L.A. (National Inst. of Standards and Technology (NCTL), Gaithersburg, MD (United States)); Dodd, N.J.F.; Lea, J.S. (Paterson Inst. for Cancer Research, Manchester (UK)); Evans, J.C.; Rowlands, C.C. (School of Chemistry and Applied Chemistry, Cardiff (UK)); Raffi, J.J.; Agnel, J.-P.L. (Laboratoire de Radiochemie des Constituants des Aliments, Cadarache (France))

    1990-01-01

    A multinational co-trial was organized to determine if electron spin resonance (ESR) spectroscopy could be used to monitor foods exposed to ionizing radiation. The bones of chicken legs, frog legs and pork rib bones were prepared and distributed as unknowns to the participating laboratories. In every instance, non-irradiated bones were correctly identified as such. Moreover, irradiated bones were not only correctly identified, but relatively good estimates of the absorbed dose were obtained. An intercomparison of the different approaches used by each laboratory is discussed, and recommendations for future trials are presented. (author).

  8. Polymorphisms in the LPL and CETP Genes and Haplotype in the ESR1 Gene Are Associated with Metabolic Syndrome in Women from Southwestern Mexico.

    Science.gov (United States)

    Cahua-Pablo, José Ángel; Cruz, Miguel; Méndez-Palacios, Abigail; Antúnez-Ortiz, Diana Lizzete; Vences-Velázquez, Amalia; del Carmen Alarcón-Romero, Luz; Parra, Esteban Juan; Tello-Flores, Vianet Argelia; Leyva-Vázquez, Marco Antonio; Valladares-Salgado, Adán; Pérez-Macedonio, Claudia Paola; Flores-Alfaro, Eugenia

    2015-09-08

    Metabolic syndrome (MetS) is a combination of metabolic disorders associated with an increased risk for cardiovascular disease (CVD). Studies in women reported associations between polymorphisms in ESR1, LPL and CETP genes and MetS. Our aim was to evaluate the association between variants in ESR1, LPL and CETP genes with MetS and its components. Four hundred and eighty women were analyzed, anthropometric features and biochemical profiles were evaluated, and genotyping was performed by real-time PCR. We found an association with elevated glucose levels (odds ratio (OR) = 2.9; p = 0.013) in carrying the AA genotype of rs1884051 in the ESR1 gene compared with the GG genotype, and the CC genotype of rs328 in the LPL gene was associated with MetS compared to the CG or GG genotype (OR = 2.8; p = 0.04). Moreover, the GA genotype of rs708272 in the CETP gene is associated with MetS compared to the GG or AA genotype (OR = 1.8; p = 0.006). In addition the ACTCCG haplotype in the ESR1 gene is associated with a decrease in the risk of MetS (OR = 0.02; p < 0.001). In conclusion, our results show the involvement of the variants of ESR1, LPL and CETP genes in metabolic events related to MetS or some of its features.

  9. Direct dating of hominids using ESR and U-series dating

    Energy Technology Data Exchange (ETDEWEB)

    Gruen, R. [Australian National University, Canberra, ACT (Australia). Research School of Earth Science

    1999-11-01

    Full text: Dating studies on palaeoanthropological sites is usually carried out on material associated with the human remains, such as the sediment, charcoal or other fauna rather than the human specimen itself. The reason lies in the fact that most dating techniques are destructive and because the hominid remains are too rare to be sacrificed for dating. This indirect dating approach is in many cases not satisfactory, because:(i) the human remains are often buried into the sediments and the association with other materials is uncertain (e.g. Skhul, Qafzeh, etc.);(ii) faunal remains or minerals from the sediment are re-worked from older deposits (see e.g. present discussion of the age of the Homo erectus remains in Indonesia);(iii) the hominid specimen was discovered at a time when no careful excavations were carried out and it is impossible to correlate the specimen with other datable material (nearly 90% of all palaeoanthropological specimen). For example, the hominid burial site of Qafzeh in Israel has been dated by several independent dating laboratories with a multitude of methods. However, the data are still not accepted by some because the dating has not been carried out on the hominid specimen. Until recently, hominid fossils could only be dated by radiocarbon. This method reaches back to about 40,000 years. As a consequence, all the older fossils could not be analysed and many important questions in our understanding of human evolution could not be addressed. Human remains are scarce and extremely valuable, therefore any sort of destruction has to be kept to an absolute minimum. This is of particular importance in Australia where any human fossils are sacred. Thus, for the analysis of hominid material it was necessary to develop a more or less non-destructive techniques. This has been accomplished in recent years by the application of ESR dating of tooth enamel and a combination of gamma spectrometric and TIMS U-series dating of bones. The examples of

  10. Acoustic Signal Feature Extraction of Vehicle Targets

    Institute of Scientific and Technical Information of China (English)

    蓝金辉; 马宝华; 李科杰

    2002-01-01

    Acoustic signal feature extraction is an important part of target recognition. The mechanisms for producing acoustic signals and their propagation are analyzed to extract the features of the radiated noise from different targets. Analysis of the acoustic spectra of typical vehicle targets acquired outdoors shows that the vehicles can be classified based on the acoustic spectra and amplitudes.

  11. Acoustic cavitation movies

    Science.gov (United States)

    Crum, Lawrence A.

    2003-04-01

    Acoustic cavitation is a phenomenon that occurs on microsecond time scales and micron length scales, yet, it has many macroscopic manifestations. Accordingly, it is often difficult, at least for the author, to form realistic physical descriptions of the specific mechanisms through which it expresses itself in our macroscopic world. For example, there are still many who believe that cavitation erosion is due to the shock wave that is emitted by bubble implosion, rather than the liquid jet created on asymmetric collapse...and they may be right. Over the years, the author has accumulated a number of movies and high-speed photographs of cavitation activity, which he uses to form his own visual references. In the time allotted, he will show a number of these movies and photographs and discuss their relevance to existing technological problems. A limited number of CDs containing the presented materials will be available to interested individuals. [Work supported in part by the NIH, USAMRMC, and the ONR.

  12. Acoustic emission testing

    CERN Document Server

    Grosse, Christian U

    2008-01-01

    Acoustic Emission (AE) techniques have been studied in civil engineering for a long time. The techniques are recently going to be more and more applied to practical applications and to be standardized in the codes. This is because the increase of aging structures and disastrous damages due to recent earthquakes urgently demand for maintenance and retrofit of civil structures in service for example. It results in the need for the development of advanced and effective inspection techniques. Thus, AE techniques draw a great attention to diagnostic applications and in material testing. The book covers all levels from the description of AE basics for AE beginners (level of a student) to sophisticated AE algorithms and applications to real large-scale structures as well as the observation of the cracking process in laboratory specimen to study fracture processes.

  13. Magnetization and ESR studies of La0.67(Ca1−xMgx)0.33MnO3 systems

    International Nuclear Information System (INIS)

    Highlights: • Mg substitution reduces the ferromagnetic strength. • Inhomogeneous broadening is due to phase separation. • Griffiths phase existence is probed. - Abstract: Magnetization studies and line shape analysis on Electron Spin Resonance (ESR) spectra of La0.67(Ca1−xMgx)0.33MnO3 are carried out. In paramagnetic phase well above Tc, the ESR spectra are single Lorentzian but below and near T∗ΔHPP, (T∗ΔHPP is temperature at which line width is minimum) inhomogeneous broadening with asymmetry in the signal is observed due to phase separation. The resonance field below T∗ΔHPP decreases with decreasing temperature. Above Tc the intensity of the ESR spectra obeys the thermally activated model (Arrhenius behavior). Substitution of Mg weakens the ferromagnetic interaction and evolution of change in lineshape near Tc is an evidence of Griffiths phase (coexistence of paramagnetic and ferromagnetic) in Mg doped LCMO system

  14. Breast cancer risk variants at 6q25 display different phenotype associations and regulate ESR1, RMND1 and CCDC170.

    Science.gov (United States)

    Dunning, Alison M; Michailidou, Kyriaki; Kuchenbaecker, Karoline B; Thompson, Deborah; French, Juliet D; Beesley, Jonathan; Healey, Catherine S; Kar, Siddhartha; Pooley, Karen A; Lopez-Knowles, Elena; Dicks, Ed; Barrowdale, Daniel; Sinnott-Armstrong, Nicholas A; Sallari, Richard C; Hillman, Kristine M; Kaufmann, Susanne; Sivakumaran, Haran; Moradi Marjaneh, Mahdi; Lee, Jason S; Hills, Margaret; Jarosz, Monika; Drury, Suzie; Canisius, Sander; Bolla, Manjeet K; Dennis, Joe; Wang, Qin; Hopper, John L; Southey, Melissa C; Broeks, Annegien; Schmidt, Marjanka K; Lophatananon, Artitaya; Muir, Kenneth; Beckmann, Matthias W; Fasching, Peter A; Dos-Santos-Silva, Isabel; Peto, Julian; Sawyer, Elinor J; Tomlinson, Ian; Burwinkel, Barbara; Marme, Frederik; Guénel, Pascal; Truong, Thérèse; Bojesen, Stig E; Flyger, Henrik; González-Neira, Anna; Perez, Jose I A; Anton-Culver, Hoda; Eunjung, Lee; Arndt, Volker; Brenner, Hermann; Meindl, Alfons; Schmutzler, Rita K; Brauch, Hiltrud; Hamann, Ute; Aittomäki, Kristiina; Blomqvist, Carl; Ito, Hidemi; Matsuo, Keitaro; Bogdanova, Natasha; Dörk, Thilo; Lindblom, Annika; Margolin, Sara; Kosma, Veli-Matti; Mannermaa, Arto; Tseng, Chiu-Chen; Wu, Anna H; Lambrechts, Diether; Wildiers, Hans; Chang-Claude, Jenny; Rudolph, Anja; Peterlongo, Paolo; Radice, Paolo; Olson, Janet E; Giles, Graham G; Milne, Roger L; Haiman, Christopher A; Henderson, Brian E; Goldberg, Mark S; Teo, Soo H; Yip, Cheng Har; Nord, Silje; Borresen-Dale, Anne-Lise; Kristensen, Vessela; Long, Jirong; Zheng, Wei; Pylkäs, Katri; Winqvist, Robert; Andrulis, Irene L; Knight, Julia A; Devilee, Peter; Seynaeve, Caroline; Figueroa, Jonine; Sherman, Mark E; Czene, Kamila; Darabi, Hatef; Hollestelle, Antoinette; van den Ouweland, Ans M W; Humphreys, Keith; Gao, Yu-Tang; Shu, Xiao-Ou; Cox, Angela; Cross, Simon S; Blot, William; Cai, Qiuyin; Ghoussaini, Maya; Perkins, Barbara J; Shah, Mitul; Choi, Ji-Yeob; Kang, Daehee; Lee, Soo Chin; Hartman, Mikael; Kabisch, Maria; Torres, Diana; Jakubowska, Anna; Lubinski, Jan; Brennan, Paul; Sangrajrang, Suleeporn; Ambrosone, Christine B; Toland, Amanda E; Shen, Chen-Yang; Wu, Pei-Ei; Orr, Nick; Swerdlow, Anthony; McGuffog, Lesley; Healey, Sue; Lee, Andrew; Kapuscinski, Miroslav; John, Esther M; Terry, Mary Beth; Daly, Mary B; Goldgar, David E; Buys, Saundra S; Janavicius, Ramunas; Tihomirova, Laima; Tung, Nadine; Dorfling, Cecilia M; van Rensburg, Elizabeth J; Neuhausen, Susan L; Ejlertsen, Bent; Hansen, Thomas V O; Osorio, Ana; Benitez, Javier; Rando, Rachel; Weitzel, Jeffrey N; Bonanni, Bernardo; Peissel, Bernard; Manoukian, Siranoush; Papi, Laura; Ottini, Laura; Konstantopoulou, Irene; Apostolou, Paraskevi; Garber, Judy; Rashid, Muhammad Usman; Frost, Debra; Izatt, Louise; Ellis, Steve; Godwin, Andrew K; Arnold, Norbert; Niederacher, Dieter; Rhiem, Kerstin; Bogdanova-Markov, Nadja; Sagne, Charlotte; Stoppa-Lyonnet, Dominique; Damiola, Francesca; Sinilnikova, Olga M; Mazoyer, Sylvie; Isaacs, Claudine; Claes, Kathleen B M; De Leeneer, Kim; de la Hoya, Miguel; Caldes, Trinidad; Nevanlinna, Heli; Khan, Sofia; Mensenkamp, Arjen R; Hooning, Maartje J; Rookus, Matti A; Kwong, Ava; Olah, Edith; Diez, Orland; Brunet, Joan; Pujana, Miquel Angel; Gronwald, Jacek; Huzarski, Tomasz; Barkardottir, Rosa B; Laframboise, Rachel; Soucy, Penny; Montagna, Marco; Agata, Simona; Teixeira, Manuel R; Park, Sue Kyung; Lindor, Noralane; Couch, Fergus J; Tischkowitz, Marc; Foretova, Lenka; Vijai, Joseph; Offit, Kenneth; Singer, Christian F; Rappaport, Christine; Phelan, Catherine M; Greene, Mark H; Mai, Phuong L; Rennert, Gad; Imyanitov, Evgeny N; Hulick, Peter J; Phillips, Kelly-Anne; Piedmonte, Marion; Mulligan, Anna Marie; Glendon, Gord; Bojesen, Anders; Thomassen, Mads; Caligo, Maria A; Yoon, Sook-Yee; Friedman, Eitan; Laitman, Yael; Borg, Ake; von Wachenfeldt, Anna; Ehrencrona, Hans; Rantala, Johanna; Olopade, Olufunmilayo I; Ganz, Patricia A; Nussbaum, Robert L; Gayther, Simon A; Nathanson, Katherine L; Domchek, Susan M; Arun, Banu K; Mitchell, Gillian; Karlan, Beth Y; Lester, Jenny; Maskarinec, Gertraud; Woolcott, Christy; Scott, Christopher; Stone, Jennifer; Apicella, Carmel; Tamimi, Rulla; Luben, Robert; Khaw, Kay-Tee; Helland, Åslaug; Haakensen, Vilde; Dowsett, Mitch; Pharoah, Paul D P; Simard, Jacques; Hall, Per; García-Closas, Montserrat; Vachon, Celine; Chenevix-Trench, Georgia; Antoniou, Antonis C; Easton, Douglas F; Edwards, Stacey L

    2016-04-01

    We analyzed 3,872 common genetic variants across the ESR1 locus (encoding estrogen receptor α) in 118,816 subjects from three international consortia. We found evidence for at least five independent causal variants, each associated with different phenotype sets, including estrogen receptor (ER(+) or ER(-)) and human ERBB2 (HER2(+) or HER2(-)) tumor subtypes, mammographic density and tumor grade. The best candidate causal variants for ER(-) tumors lie in four separate enhancer elements, and their risk alleles reduce expression of ESR1, RMND1 and CCDC170, whereas the risk alleles of the strongest candidates for the remaining independent causal variant disrupt a silencer element and putatively increase ESR1 and RMND1 expression. PMID:26928228

  15. Breast cancer risk variants at 6q25 display different phenotype associations and regulate ESR1, RMND1 and CCDC170

    Science.gov (United States)

    Dunning, Alison M; Michailidou, Kyriaki; Kuchenbaecker, Karoline B; Thompson, Deborah; French, Juliet D; Beesley, Jonathan; Healey, Catherine S; Kar, Siddhartha; Pooley, Karen A; Lopez-Knowles, Elena; Dicks, Ed; Barrowdale, Daniel; Sinnott-Armstrong, Nicholas A; Sallari, Richard C; Hillman, Kristine M; Kaufmann, Susanne; Sivakumaran, Haran; Marjaneh, Mahdi Moradi; Lee, Jason S; Hills, Margaret; Jarosz, Monika; Drury, Suzie; Canisius, Sander; Bolla, Manjeet K; Dennis, Joe; Wang, Qin; Hopper, John L; Southey, Melissa C; Broeks, Annegien; Schmidt, Marjanka K; Lophatananon, Artitaya; Muir, Kenneth; Beckmann, Matthias W; Fasching, Peter A; dos-Santos-Silva, Isabel; Peto, Julian; Sawyer, Elinor J; Tomlinson, Ian; Burwinkel, Barbara; Marme, Frederik; Guénel, Pascal; Truong, Thérèse; Bojesen, Stig E; Flyger, Henrik; González-Neira, Anna; Perez, Jose I A; Anton-Culver, Hoda; Eunjung, Lee; Arndt, Volker; Brenner, Hermann; Meindl, Alfons; Schmutzler, Rita K; Brauch, Hiltrud; Hamann, Ute; Aittomäki, Kristiina; Blomqvist, Carl; Ito, Hidemi; Matsuo, Keitaro; Bogdanova, Natasha; Dörk, Thilo; Lindblom, Annika; Margolin, Sara; Kosma, Veli-Matti; Mannermaa, Arto; Tseng, Chiu-chen; Wu, Anna H; Lambrechts, Diether; Wildiers, Hans; Chang-Claude, Jenny; Rudolph, Anja; Peterlongo, Paolo; Radice, Paolo; Olson, Janet E; Giles, Graham G; Milne, Roger L; Haiman, Christopher A; Henderson, Brian E; Goldberg, Mark S; Teo, Soo H; Yip, Cheng Har; Nord, Silje; Borresen-Dale, Anne-Lise; Kristensen, Vessela; Long, Jirong; Zheng, Wei; Pylkäs, Katri; Winqvist, Robert; Andrulis, Irene L; Knight, Julia A; Devilee, Peter; Seynaeve, Caroline; Figueroa, Jonine; Sherman, Mark E; Czene, Kamila; Darabi, Hatef; Hollestelle, Antoinette; van den Ouweland, Ans M W; Humphreys, Keith; Gao, Yu-Tang; Shu, Xiao-Ou; Cox, Angela; Cross, Simon S; Blot, William; Cai, Qiuyin; Ghoussaini, Maya; Perkins, Barbara J; Shah, Mitul; Choi, Ji-Yeob; Kang, Daehee; Lee, Soo Chin; Hartman, Mikael; Kabisch, Maria; Torres, Diana; Jakubowska, Anna; Lubinski, Jan; Brennan, Paul; Sangrajrang, Suleeporn; Ambrosone, Christine B; Toland, Amanda E; Shen, Chen-Yang; Wu, Pei-Ei; Orr, Nick; Swerdlow, Anthony; McGuffog, Lesley; Healey, Sue; Lee, Andrew; Kapuscinski, Miroslav; John, Esther M; Terry, Mary Beth; Daly, Mary B; Goldgar, David E; Buys, Saundra S; Janavicius, Ramunas; Tihomirova, Laima; Tung, Nadine; Dorfling, Cecilia M; van Rensburg, Elizabeth J; Neuhausen, Susan L; Ejlertsen, Bent; Hansen, Thomas V O; Osorio, Ana; Benitez, Javier; Rando, Rachel; Weitzel, Jeffrey N; Bonanni, Bernardo; Peissel, Bernard; Manoukian, Siranoush; Papi, Laura; Ottini, Laura; Konstantopoulou, Irene; Apostolou, Paraskevi; Garber, Judy; Rashid, Muhammad Usman; Frost, Debra; Izatt, Louise; Ellis, Steve; Godwin, Andrew K; Arnold, Norbert; Niederacher, Dieter; Rhiem, Kerstin; Bogdanova-Markov, Nadja; Sagne, Charlotte; Stoppa-Lyonnet, Dominique; Damiola, Francesca; Sinilnikova, Olga M; Mazoyer, Sylvie; Isaacs, Claudine; Claes, Kathleen B M; De Leeneer, Kim; de la Hoya, Miguel; Caldes, Trinidad; Nevanlinna, Heli; Khan, Sofia; Mensenkamp, Arjen R; Hooning, Maartje J; Rookus, Matti A; Kwong, Ava; Olah, Edith; Diez, Orland; Brunet, Joan; Pujana, Miquel Angel; Gronwald, Jacek; Huzarski, Tomasz; Barkardottir, Rosa B; Laframboise, Rachel; Soucy, Penny; Montagna, Marco; Agata, Simona; Teixeira, Manuel R; Park, Sue Kyung; Lindor, Noralane; Couch, Fergus J; Tischkowitz, Marc; Foretova, Lenka; Vijai, Joseph; Offit, Kenneth; Singer, Christian F; Rappaport, Christine; Phelan, Catherine M; Greene, Mark H; Mai, Phuong L; Rennert, Gad; Imyanitov, Evgeny N; Hulick, Peter J; Phillips, Kelly-Anne; Piedmonte, Marion; Mulligan, Anna Marie; Glendon, Gord; Bojesen, Anders; Thomassen, Mads; Caligo, Maria A; Yoon, Sook-Yee; Friedman, Eitan; Laitman, Yael; Borg, Ake; von Wachenfeldt, Anna; Ehrencrona, Hans; Rantala, Johanna; Olopade, Olufunmilayo I; Ganz, Patricia A; Nussbaum, Robert L; Gayther, Simon A; Nathanson, Katherine L; Domchek, Susan M; Arun, Banu K; Mitchell, Gillian; Karlan, Beth Y; Lester, Jenny; Maskarinec, Gertraud; Woolcott, Christy; Scott, Christopher; Stone, Jennifer; Apicella, Carmel; Tamimi, Rulla; Luben, Robert; Khaw, Kay-Tee; Helland, Åslaug; Haakensen, Vilde; Dowsett, Mitch; Pharoah, Paul D P; Simard, Jacques; Hall, Per; García-Closas, Montserrat; Vachon, Celine; Chenevix-Trench, Georgia; Antoniou, Antonis C; Easton, Douglas F; Edwards, Stacey L

    2016-01-01

    We analyzed 3,872 common genetic variants across the ESR1 locus (encoding estrogen receptor α) in 118,816 subjects from three international consortia. We found evidence for at least five independent causal variants, each associated with different phenotype sets, including estrogen receptor (ER+ or ER−) and human ERBB2 (HER2+ or HER2−) tumor subtypes, mammographic density and tumor grade. The best candidate causal variants for ER− tumors lie in four separate enhancer elements, and their risk alleles reduce expression of ESR1, RMND1 and CCDC170, whereas the risk alleles of the strongest candidates for the remaining independent causal variant disrupt a silencer element and putatively increase ESR1 and RMND1 expression. PMID:26928228

  16. Effects of subsampling of passive acoustic recordings on acoustic metrics.

    Science.gov (United States)

    Thomisch, Karolin; Boebel, Olaf; Zitterbart, Daniel P; Samaran, Flore; Van Parijs, Sofie; Van Opzeeland, Ilse

    2015-07-01

    Passive acoustic monitoring is an important tool in marine mammal studies. However, logistics and finances frequently constrain the number and servicing schedules of acoustic recorders, requiring a trade-off between deployment periods and sampling continuity, i.e., the implementation of a subsampling scheme. Optimizing such schemes to each project's specific research questions is desirable. This study investigates the impact of subsampling on the accuracy of two common metrics, acoustic presence and call rate, for different vocalization patterns (regimes) of baleen whales: (1) variable vocal activity, (2) vocalizations organized in song bouts, and (3) vocal activity with diel patterns. To this end, above metrics are compared for continuous and subsampled data subject to different sampling strategies, covering duty cycles between 50% and 2%. The results show that a reduction of the duty cycle impacts negatively on the accuracy of both acoustic presence and call rate estimates. For a given duty cycle, frequent short listening periods improve accuracy of daily acoustic presence estimates over few long listening periods. Overall, subsampling effects are most pronounced for low and/or temporally clustered vocal activity. These findings illustrate the importance of informed decisions when applying subsampling strategies to passive acoustic recordings or analyses for a given target species. PMID:26233026

  17. ESR1/SYNE1 polymorphism and invasive epithelial ovarian cancer risk: an Ovarian Cancer Association Consortium study

    DEFF Research Database (Denmark)

    Doherty, Jennifer A; Rossing, Mary Anne; Cushing-Haugen, Kara L;

    2010-01-01

    We genotyped 13 single nucleotide polymorphisms (SNPs) in the estrogen receptor alpha gene (ESR1) region in three population-based case-control studies of epithelial ovarian cancer conducted in the United States, comprising a total of 1,128 and 1,866 non-Hispanic white invasive cases and controls......, respectively. A SNP 19 kb downstream of ESR1 (rs2295190, G-to-T change) was associated with invasive ovarian cancer risk, with a per-T-allele odds ratio (OR) of 1.24 [95% confidence interval (CI), 1.06-1.44, P = 0.006]. rs2295190 is a nonsynonymous coding SNP in a neighboring gene called spectrin repeat...... containing, nuclear envelope 1 (SYNE1), which is involved in nuclear organization and structural integrity, function of the Golgi apparatus, and cytokinesis. An isoform encoded by SYNE1 has been reported to be downregulated in ovarian and other cancers. rs2295190 was genotyped in an additional 12 studies...

  18. Interlaboratory tests to identify irradiation treatment of various foods via gas chromatographic detection of hydrocarbons, ESR spectroscopy and TL analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, G.A.; Helle, N.; Schulzki, G.; Linke, B.; Spiegelberg, A.; Mager, M.; Boegl, K.W. [BgVV - Federal Inst. for Health Protection of Consumers and Veterinary Medicine, Berlin (Germany)

    1996-12-31

    The gas chromatographic (GC) analysis of radiation-induced volatile hydrocarbons (HC) and 2-alkylcyclobutanones, the ESR spectroscopic detection of radiation-specific radicals and the thermoluminescence (TL) analysis of silicate mineral are the most important methods for identification of irradiated foods. After successful performance in interlaboratory studies on meat products, fish, spices, herbs and shells of nuts, all or some of these methods have been approved by national authorities in Germany and the United Kingdom. Recently, draft European Standards have been elaborated for approval by member states of the European Committee for Standardization (CEN). Several research laboratories have shown that these methods can be applied to various foods not yet tested in collaborative studies. However, for an effective application in food control it is necessary to prove their suitability in interlaboratory studies. Therefore, in 1993/94, various interlaboratory tests were organised by the BgVV. In an ESR spectroscopic test, shrimps and paprika powder were examined. Shrimps were also the subject of examination in a TL test. Finally, GC detection of radiation-induced hydrocarbons in the fat fraction of foods was used in another test to identify irradiated Camembert, avocado, papaya and mango. In the following paper, results of the interlaboratory tests are summarised. Detailed reports are published by this institute. (author).

  19. Structure of very heavy few-electron ions - new results from the heavy ion storage ring, ESR

    International Nuclear Information System (INIS)

    The heavy ion synchrotron/storage ring facility at GSI, SIS/ESR, provides intense beams of cooled, highly-charged ions up to naked uranium (U92+). By electron capture during ion-atom collisions in the gas target of the ESR or by recombination at ion-electron encounters in the ''electron cooler'' excited states are populated. The detailed structure of very heavy one-, two- and three-electron ions is studied. The different mechanisms leading to the excited states are described, as well as the new experimental tools now available for a detailed spectroscopy of these interesting systems. Special emphasis is given to X-ray transitions to the groundstates in H- and He-like systems. For the heaviest species the groundstate Lambshift can now be probed on an accuracy level of better than 10% using solid-state X-ray detectors. Applying dispersive X-ray analyzing techniques, this accuracy will certainly be improved in future. However, utilizing the dielectronic resonances for a spectroscopy, the structure in Li-like heavy ions can already be probed now on the sub eV level. (orig.)

  20. Interlaboratory tests to identify irradiation treatment of various foods via gas chromatographic detection of hydrocarbons, ESR spectroscopy and TL analysis

    International Nuclear Information System (INIS)

    The gas chromatographic (GC) analysis of radiation-induced volatile hydrocarbons (HC) and 2-alkylcyclobutanones, the ESR spectroscopic detection of radiation-specific radicals and the thermoluminescence (TL) analysis of silicate mineral are the most important methods for identification of irradiated foods. After successful performance in interlaboratory studies on meat products, fish, spices, herbs and shells of nuts, all or some of these methods have been approved by national authorities in Germany and the United Kingdom. Recently, draft European Standards have been elaborated for approval by member states of the European Committee for Standardization (CEN). Several research laboratories have shown that these methods can be applied to various foods not yet tested in collaborative studies. However, for an effective application in food control it is necessary to prove their suitability in interlaboratory studies. Therefore, in 1993/94, various interlaboratory tests were organised by the BgVV. In an ESR spectroscopic test, shrimps and paprika powder were examined. Shrimps were also the subject of examination in a TL test. Finally, GC detection of radiation-induced hydrocarbons in the fat fraction of foods was used in another test to identify irradiated Camembert, avocado, papaya and mango. In the following paper, results of the interlaboratory tests are summarised. Detailed reports are published by this institute. (author)

  1. Study of intrinsic energy dependence of α-alanine and dose intercomparison with ESR and ISE techniques

    International Nuclear Information System (INIS)

    The intrinsic energy behavior of the radiation chemical yields G(R ·) and G(NH3) which determine the dose response for the alanine/ESR and alanine/Ion-Selective Electrode (ISE) system, is an important characteristic for the consistent use in different radiation environments. Therefore, the response of ISS and Gent α-alanine dosimeters in the dose range 0.1 to 700 kGy was examined with 60Co, bremsstrahlung and electron beam radiation. Bremsstrahlung beams with end point energy between 5 and 12 MeV and electron beams with mean energy at the effective point of measurement between 4 and 25 MeV were used. Analysis of the 60Co calibration results shows that there are no significant differences in dose determination between the two laboratories. The statistical evaluation of 41 sets of independent series of measurements has shown no significant variation with beam energy. The results also confirm good consistency between ISE and ESR measurements. (author)

  2. Dose estimation by ESR on tooth enamel from two workers exposed to radiation due to the JCO accident

    International Nuclear Information System (INIS)

    Electron spin resonance (ESR) dosimetry is useful to estimate the external dose for the general population as well as for occupational workers in a nuclear emergency. Three teeth were extracted from two exposed workers (A and B) related to the JCO criticality accident. Tooth enamel was carefully separated from other tooth parts and subjected to ESR dosimetry. Doses equivalent to the γ-ray dose of 60Co were estimated as follows: for worker A, the buccal and lingual sides of the eighth tooth in the upper right side, 11.8±3.6 and 12.0±3.6 Gy, respectively; for worker B, the buccal and lingual sides of the fourth tooth in the upper right side and the fifth tooth in the upper left side, 11.3±3.4 and 10.8±3.3 Gy, 11.7±3.5 and 11.4±3.4 Gy, respectively. The estimated doses were found to be similar and not dependent on the tooth positions, whether the buccal or lingual sides in each tooth. (author)

  3. Endocrine-Therapy-Resistant ESR1 Variants Revealed by Genomic Characterization of Breast-Cancer-Derived Xenografts

    Directory of Open Access Journals (Sweden)

    Shunqiang Li

    2013-09-01

    Full Text Available To characterize patient-derived xenografts (PDXs for functional studies, we made whole-genome comparisons with originating breast cancers representative of the major intrinsic subtypes. Structural and copy number aberrations were found to be retained with high fidelity. However, at the single-nucleotide level, variable numbers of PDX-specific somatic events were documented, although they were only rarely functionally significant. Variant allele frequencies were often preserved in the PDXs, demonstrating that clonal representation can be transplantable. Estrogen-receptor-positive PDXs were associated with ESR1 ligand-binding-domain mutations, gene amplification, or an ESR1/YAP1 translocation. These events produced different endocrine-therapy-response phenotypes in human, cell line, and PDX endocrine-response studies. Hence, deeply sequenced PDX models are an important resource for the search for genome-forward treatment options and capture endocrine-drug-resistance etiologies that are not observed in standard cell lines. The originating tumor genome provides a benchmark for assessing genetic drift and clonal representation after transplantation.

  4. Hybrid optical and acoustic force based sorting

    Science.gov (United States)

    O'Mahoney, Paul; Brodie, Graham W.; Wang, Han; Demore, Christine E. M.; Cochran, Sandy; Spalding, Gabriel C.; MacDonald, Michael P.

    2014-09-01

    We report the combined use of optical sorting and acoustic levitation to give particle sorting. Differing sizes of microparticles are sorted optically both with and without the aid of acoustic levitation, and the results compared to show that the use of acoustic trapping can increase sorting efficiency. The use of a transparent ultrasonic transducer is also shown to streamline the integration of optics and acoustics. We also demonstrate the balance of optical radiation pressure and acoustic levitation to achieve vertical sorting.

  5. Electron Spin Resonance (ESR) and Thermoluminescence (TL) studies of stalagmitic floors of the Caune de de L'Arago at Tautavel (France)

    International Nuclear Information System (INIS)

    The geological radiation dose to the stalagmites of various stratigraphic levels of the Caune de L'Arago at Tautavel has been measured by Thermoluminescence (TL) and Electron Spin Resonance (ESR). In all samples the TL natural spectrum a well developped 2800C peak and a subordinate 3500C peak, while the ESR line spectrum may present the h1, h2 and h3 radiative lines of Yokoyama et al.) or only h2. All TL peaks and ESR lines do increase with the laboratory applied radiation (β or γ) doses. The activated h2 line is visibly unstable in laboratory conditions as well as apparently the h3 line in one sample. Within the experimental precision, the geological doses determined from the 280C peak and h3 line on one band and the 3500C peak and h1 line (after thermal treatment of the later, see Yokoyama et al. on the other hand are identical. When the 280C natural peak is visibly affected by natural fading as shown by the plateau test, so is h3, and the geological doses of the 2800C-h3 peaks are lowered by the same factor as compared to those of the 3500C-h1 peaks. Annealing experiments show that the relationships between the TL and ESR peaks may be difficult to analyse in some samples due to the possible occurence of non radiative components in some ESR lines. Such components appear clearly at temperatures above approx. 180-2000C and might possibly be present below. This may have important implications for the selection of samples to be dated by ESR. (Author)

  6. ESR1 gene promoter region methylation in free circulating DNA and its correlation with estrogen receptor protein expression in tumor tissue in breast cancer patients

    International Nuclear Information System (INIS)

    Tumor expression of estrogen receptor (ER) is an important marker of prognosis, and is predictive of response to endocrine therapy in breast cancer. Several studies have observed that epigenetic events, such methylation of cytosines and deacetylation of histones, are involved in the complex mechanisms that regulate promoter transcription. However, the exact interplay of these factors in transcription activity is not well understood. In this study, we explored the relationship between ER expression status in tumor tissue samples and the methylation of the 5′ CpG promoter region of the estrogen receptor gene (ESR1) isolated from free circulating DNA (fcDNA) in plasma samples from breast cancer patients. Patients (n = 110) with non-metastatic breast cancer had analyses performed of ER expression (luminal phenotype in tumor tissue, by immunohistochemistry method), and the ESR1-DNA methylation status (fcDNA in plasma, by quantitative methylation specific PCR technique). Our results showed a significant association between presence of methylated ESR1 in patients with breast cancer and ER negative status in the tumor tissue (p = 0.0179). There was a trend towards a higher probability of ESR1-methylation in those phenotypes with poor prognosis i.e. 80% of triple negative patients, 60% of HER2 patients, compared to 28% and 5.9% of patients with better prognosis such as luminal A and luminal B, respectively. Silencing, by methylation, of the promoter region of the ESR1 affects the expression of the estrogen receptor protein in tumors of breast cancer patients; high methylation of ESR1-DNA is associated with estrogen receptor negative status which, in turn, may be implicated in the patient’s resistance to hormonal treatment in breast cancer. As such, epigenetic markers in plasma may be of interest as new targets for anticancer therapy, especially with respect to endocrine treatment

  7. Spin Labeling ESR Investigation of a Role of Humic Acids at Covalent Binding of Xenobiotics to Soil

    Science.gov (United States)

    Aleksandrova, Olga

    2014-05-01

    The environmental risk of organic xenobiotic chemicals released into soils is controlled by their sorption and binding processes. However, the molecular mechanisms of reversible and irreversible interactions of xenobiotics with soil constituents and an influence of humic substances on this interaction are only partly understood. New methods and approaches aimed at understanding of molecular mechanisms in the soil environment and a role of humic substances in the sorption and binding processes are today required to manage and keep the quality of soil used and fertilized in agricultural industry. The paper presents a new approach of using stable ESR spin labels to investigate a role of humic substances in the interactions of organic xenobiotic chemicals with constituents of natural soil via the typical functional groups of xenobiotics, such as Amines. At the experiment, the nitroxide spin labels, such as TEMPO (2,2,6,6-Tetramethylpiperidin-1-oxyl), Amino-TEMPO (4-amino-2,2,6,6-Tetramethylpiperidin-1-oxyl) and Aniline spin labels (2,5,5-Trimethyl-2-(3-aminophenyl)pyrrolidin-1-oxyl), were added to samples of different natural soils, such luvisol, cambisol and chernozem. Amino-TEMPO and Aniline spin labels include the aliphatic amino and aromatic amino functional groups, respectively. A significant broadening of the ESR spectrum of Aniline spin labels incubated in different soils indicated a stable effect of covalent binding of the spin labels to soil constituents via the aromatic amino, whereas the ESR spectra of the other two spin labels were not broadened that pointed at the absence of covalent binding of spin labels via the aliphatic amino. As shown, a part of bound spin labels via the aromatic amino increased with increasing of the concentration of humic acids in soil. The same broadened signals were also be detected with the humic acids extracted from the investigated soils. A strong covalent binding of spin labels to humic substances via the aromatic amines was

  8. Frequency Steered Acoustic Transducer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase II project is to fabricate, characterize, and verify performance of a new type of frequency steered acoustic...

  9. Frequency Steered Acoustic Transducer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project is to develop, fabricate, and characterize a novel frequency steered acoustic transducer (FSAT) for the...

  10. Reverberant Acoustic Test Facility (RATF)

    Data.gov (United States)

    Federal Laboratory Consortium — The very large Reverberant Acoustic Test Facility (RATF) at the NASA Glenn Research Center (GRC), Plum Brook Station, is currently under construction and is due to...

  11. Cryogenic Acoustic Suppression Testing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed project will explore and test the feasibility and effectiveness of using a cryogenic fluid (liquid nitrogen) to facilitate acoustic suppression in a...

  12. NEAR-FIELD ACOUSTIC HOLOGRAPHY FOR SEMI-FREE ACOUSTIC FIELD BASED ON WAVE SUPERPOSITION APPROACH

    Institute of Scientific and Technical Information of China (English)

    LI Weibing; CHEN Jian; YU Fei; CHEN Xinzhao

    2006-01-01

    In the semi-free acoustic field, the actual acoustic pressure at any point is composed of two parts: The direct acoustic pressure and the reflected acoustic pressure. The general acoustic holographic theories and algorithms request that there is only the direct acoustic pressure contained in the pressure at any point on the hologram surface, consequently, they cannot be used to reconstruct acoustic source and predict acoustic field directly. To take the reflected pressure into consideration, near-field acoustic holography for semi-free acoustic field based on wave superposition approach is proposed to realize the holographic reconstruction and prediction of the semi-free acoustic field, and the wave superposition approach is adopted as a holographic transform algorithm. The proposed theory and algorithm are realized and verified with a numerical example,and the drawbacks of the general theories and algorithms in the holographic reconstruction and prediction of the semi-free acoustic field are also demonstrated by this numerical example.

  13. ESR dosimetry using inorganic materials: a case study of Li{sub 2}CO{sub 3} and CaSO{sub 4}:Dy as prospective dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Murali, S. E-mail: rssdrhcs@magnum.barc.ernet.in; Natarajan, V.; Venkataramani, R.; Pushparaja; Sastry, M.D

    2001-08-01

    The CO{sub 2}{sup -} radical ion, detected by ESR technique in bones and teeth enamel, was proved to be invaluable in high level and retrospective dosimetry. In these matrices, impurity carbonate (at phosphate sites) was the precursor to CO{sub 2}{sup -} With a view to investigate the possibility of using inorganic materials such as lithium carbonate as ESR dosimeters, studies were carried out on gamma-irradiated Li{sub 2}CO{sub 3} . The intensity of radiation-induced ESR signals of Li{sub 2}CO{sub 3} at g=2.0036 (CO{sub 3}{sup -}) and g=2.0006 (CO{sub 2}{sup -}) was followed as a function of gamma dose in the low dose range of 1- 1350 Gy. It was observed that the intensity of the ESR signal at g=2.0036 (CO{sub 3}{sup -}) was in a linear relation with the radiation dose in the dose range 10- 800 Gy and the signal at g=2.0006 (CO{sub 2}{sup -}) showed linear response in the dose range 5- 800 Gy. The lowest dose that could be detected in the present studies using the signal of CO{sub 2}{sup -} in Li{sub 2}CO{sub 3} powder samples ({approx}50 mg) is 3.2 Gy. ESR studies were also carried out on the widely used TL dosimetric material CaSO{sub 4} : Dy and in pure CaSO{sub 4} after gamma irradiation. The TL materials were used in powder as well as pellet forms. The linearity of ESR response with dose for powder and pellet forms of CaSO{sub 4} : Dy was also studied using the signals at g=2.0030 (SO{sub 3}{sup -}) and at g=2.0139 (SO{sub 4}{sup -}). It was observed that the range of linearity of dose response extended between 20 and 1200 Gy, for SO{sub 3}{sup -} signals. The results of dosimetric study indicate that the ESR-Li{sub 2}CO{sub 3} system could be used in dosimetric applications in radiotherapy. However, for the actual applications further advancement is needed to lower the detection limit. The TL phosphor, CaSO{sub 4}:Dy in powder and pellet forms, could be used as ESR dosimeter in the dose range 20-600 Gy.

  14. The Application of Long Esr Sensor Rods for Neutron and Gamma Dosimetry of the "weak" In-Reactor Irradiation of the Htgr Fuel

    Science.gov (United States)

    Usatyi, A. F.; Momot, G. V.; Kaynov, V. B.; Kuznetsov, A. I.

    2003-06-01

    In order to measure the general spatial distribution of the thermal neutron fluence during the so called "weak" irradiation (less than 1017 n/m2) of HTGR nuclear fuel for subsequent high temperature tests including fission products release, we apply local (0.3 cm rings) and distributed (long rods up to 65 cm) accumulative detectors of neutrons and gamma with results' reading by the electron spin resonance method (ESR-sensors). Sensors materials are: silicate ceramic (glass) containing B2O3 (neutron sensor) and quartz with Al2O3 addition (gamma sensor). The new possibilities of nontraditional ESR-sensors, a new type of nuclear radiation detectors are discussed.

  15. Acoustic Rectification in Dispersive Media

    Science.gov (United States)

    Cantrell, John H.

    2008-01-01

    It is shown that the shapes of acoustic radiation-induced static strain and displacement pulses (rectified acoustic pulses) are defined locally by the energy density of the generating waveform. Dispersive properties are introduced analytically by assuming that the rectified pulses are functionally dependent on a phase factor that includes both dispersive and nonlinear terms. The dispersion causes an evolutionary change in the shape of the energy density profile that leads to the generation of solitons experimentally observed in fused silica.

  16. Simplified Rotation In Acoustic Levitation

    Science.gov (United States)

    Barmatz, M. B.; Gaspar, M. S.; Trinh, E. H.

    1989-01-01

    New technique based on old discovery used to control orientation of object levitated acoustically in axisymmetric chamber. Method does not require expensive equipment like additional acoustic drivers of precisely adjustable amplitude, phase, and frequency. Reflecting object acts as second source of sound. If reflecting object large enough, close enough to levitated object, or focuses reflected sound sufficiently, Rayleigh torque exerted on levitated object by reflected sound controls orientation of object.

  17. Stable And Oscillating Acoustic Levitation

    Science.gov (United States)

    Barmatz, Martin B.; Garrett, Steven L.

    1988-01-01

    Sample stability or instability determined by levitating frequency. Degree of oscillation of acoustically levitated object along axis of levitation chamber controlled by varying frequency of acoustic driver for axis above or below frequency of corresponding chamber resonance. Stabilization/oscillation technique applied in normal Earth gravity, or in absence of gravity to bring object quickly to rest at nominal levitation position or make object oscillate in desired range about that position.

  18. Study Acoustic Emissions from Composites

    Science.gov (United States)

    Walker, James; Workman,Gary

    1998-01-01

    The purpose of this work will be to develop techniques for monitoring the acoustic emissions from carbon epoxy composite structures at cryogenic temperatures. Performance of transducers at temperatures ranging from ambient to cryogenic and the characteristics of acoustic emission from composite structures will be studied and documented. This entire effort is directed towards characterization of structures used in NASA propulsion programs such as the X-33.

  19. Opto-acoustic cell permeation

    Energy Technology Data Exchange (ETDEWEB)

    Visuri, S R; Heredia, N

    2000-03-09

    Optically generated acoustic waves have been used to temporarily permeate biological cells. This technique may be useful for enhancing transfection of DNA into cells or enhancing the absorption of locally delivered drugs. A diode-pumped frequency-doubled Nd:YAG laser operating at kHz repetition rates was used to produce a series of acoustic pulses. An acoustic wave was formed via thermoelastic expansion by depositing laser radiation into an absorbing dye. Generated pressures were measured with a PVDF hydrophone. The acoustic waves were transmitted to cultured and plated cells. The cell media contained a selection of normally- impermeable fluorescent-labeled dextran dyes. Following treatment with the opto-acoustic technique, cellular incorporation of dyes, up to 40,000 Molecular Weight, was noted. Control cells that did not receive opto-acoustic treatment had unremarkable dye incorporation. Uptake of dye was quantified via fluorescent microscopic analysis. Trypan Blue membrane exclusion assays and fluorescent labeling assays confirmed the vitality of cells following treatment. This method of enhanced drug delivery has the potential to dramatically reduce required drug dosages and associated side effects and enable revolutionary therapies.

  20. Prediction of acoustic comfort and acoustic silence in Goan Catholic churches

    OpenAIRE

    Menino A. S. M. P. Tavares; S. Rajagopalan; Satish J. Sharma; António P. O. Carvalho

    2009-01-01

    Acoustic Comfort and Acoustic Silence are determinants of tranquility in a worship space. The results presented here are part of a study that investigates the behaviour of acoustically constituted worship parameters in six Catholic churches (Goa, India). Acoustic comfort is quantified through an Acoustic Comfort Impression Index which measures the net comfort induced through the optimization of the desired subjective acoustic impressions for different types of music and different music source...

  1. Acoustic Signal Processing

    Science.gov (United States)

    Hartmann, William M.; Candy, James V.

    Signal processing refers to the acquisition, storage, display, and generation of signals - also to the extraction of information from signals and the re-encoding of information. As such, signal processing in some form is an essential element in the practice of all aspects of acoustics. Signal processing algorithms enable acousticians to separate signals from noise, to perform automatic speech recognition, or to compress information for more efficient storage or transmission. Signal processing concepts are the building blocks used to construct models of speech and hearing. Now, in the 21st century, all signal processing is effectively digital signal processing. Widespread access to high-speed processing, massive memory, and inexpensive software make signal processing procedures of enormous sophistication and power available to anyone who wants to use them. Because advanced signal processing is now accessible to everybody, there is a need for primers that introduce basic mathematical concepts that underlie the digital algorithms. The present handbook chapter is intended to serve such a purpose.

  2. Acoustics of the Intonarumori

    Science.gov (United States)

    Serafin, Stefania

    2005-04-01

    The Intonarumori were a family of musical instruments invented by the Italian futurist composer and painter Luigi Russolo. Each Intonarumori was made of a wooden parallelepiped sound box, inside which a wheel of different sizes and materials was setting into vibration a catgut or metal string. The pitch of the string was varied by using a lever, while the speed of the wheel was controlled by the performer using a crank. At one end of the string there was a drumhead that transmitted vibrations to the speaker. Unfortunately, all the original Intonarumori were destroyed after a fire during World War II. Since then, researchers have tried to understand the sound production mechanism of such instruments, especially by consulting the patents compiled by Russolo or by reading his book ``The art of noise.'' In this paper we describe the acoustics of the Intonarumori. Based on such description, we propose physical models that simulate such instruments. The intonarumori's string is modeled using a one dimensional waveguide, which is excited either by an impact or a friction model. The body of the instrument is modeled using a 3-D rectangular mesh, while the horn is considered as an omnidirectional radiator.

  3. Microwave Absorption Studies on HIGH-Tc Superconductors and Related Materials VII — Esr of Dpph Coated on a Thin BiSrCaCuO Film Fabricated on MgO(100) Substrate

    Science.gov (United States)

    Sugawara, K.; Sugimoto, T.; Shiohara, Y.; Tanaka, S.

    ESR of DPPH coated on a Bi-Sr-Ca-Cu-O (BSCCO) film (350 Å thick) fabricated on MgO(100) substrate by MOCVD was studied. Temperature dependence of the ESR peak-to-peak linewidth, ΔHpp, and the effect of applied magnetic field on ΔHpp have been studied below about 100 K. The results were compared with those of ESR of DPPH coated on ceramic Y-Ba-Cu-O samples (powder and bulk) made by the MPMG method. The DPPH ESR for the BSCCO film revealed that ΔHpp was independent of applied magnetic field up to about 9 kG. In addition, no similarity between the temperature dependence of the excess ESR linewidth of the DPPH and that of critical current density was found for the BSCCO film. These results for the BSCCO film are different from those for the MPMG YBCO samples.

  4. Microwave absorption studies on high-Tc superconductors and related materials 7--ESR of DPPH coated on a thin BiSrCaCuO film fabricated on MgO(100) substrate

    International Nuclear Information System (INIS)

    In this paper, ESR of DPPH coated on a Bi-Sr-Ca-Cu-O (BSCCO) film (350 Angstrom thick) fabricated on MgO(100) substrate by MOCVD is studied. Temperature dependence of the ESR peak-to-peak linewidth, ΔHpp, and the effect of applied magnetic field on ΔHpp are below about 100 K. The results are compared with those of ESR of DPPH coated on ceramic Y-Ba-Cu-O samples (powder and bulk) made by the MPMG method. The DPPH ESR for the BSCCO film reveals that ΔHpp was independent of applied magnetic field up to about 9 kG. In addition, no similarity between the temperature dependence of the excess ESR linewidth of the DPPH and that of critical current density was found for the BSCCO film. These results for the BSCCO film are different from those for the MPMG YBCO samples

  5. Focusing of Acoustic Waves through Acoustic Materials with Subwavelength Structures

    KAUST Repository

    Xiao, Bingmu

    2013-05-01

    In this thesis, wave propagation through acoustic materials with subwavelength slits structures is studied. Guided by the findings, acoustic wave focusing is achieved with a specific material design. By using a parameter retrieving method, an effective medium theory for a slab with periodic subwavelength cut-through slits is successfully derived. The theory is based on eigenfunction solutions to the acoustic wave equation. Numerical simulations are implemented by the finite-difference time-domain (FDTD) method for the two-dimensional acoustic wave equation. The theory provides the effective impedance and refractive index functions for the equivalent medium, which can reproduce the transmission and reflection spectral responses of the original structure. I analytically and numerically investigate both the validity and limitations of the theory, and the influences of material and geometry on the effective spectral responses are studied. Results show that large contrasts in impedance and density are conditions that validate the effective medium theory, and this approximation displays a better accuracy for a thick slab with narrow slits in it. Based on the effective medium theory developed, a design of a at slab with a snake shaped" subwavelength structure is proposed as a means of achieving acoustic focusing. The property of focusing is demonstrated by FDTD simulations. Good agreement is observed between the proposed structure and the equivalent lens pre- dicted by the theory, which leads to robust broadband focusing by a thin at slab.

  6. Acoustic communication in plant-animal interactions.

    Science.gov (United States)

    Schöner, Michael G; Simon, Ralph; Schöner, Caroline R

    2016-08-01

    Acoustic communication is widespread and well-studied in animals but has been neglected in other organisms such as plants. However, there is growing evidence for acoustic communication in plant-animal interactions. While knowledge about active acoustic signalling in plants (i.e. active sound production) is still in its infancy, research on passive acoustic signalling (i.e. reflection of animal sounds) revealed that bat-dependent plants have adapted to the bats' echolocation systems by providing acoustic reflectors to attract their animal partners. Understanding the proximate mechanisms and ultimate causes of acoustic communication will shed light on an underestimated dimension of information transfer between plants and animals. PMID:27423052

  7. Modelling of acoustic transmission through perforated layer

    Directory of Open Access Journals (Sweden)

    Lukeš V.

    2007-10-01

    Full Text Available The paper deals with modeling the acoustic transmission through a perforated interface plane separating two halfspaces occupied by the acoustic medium. We considered the two-scale homogenization limit of the standard acoustic problem imposed in the layer with the perforated periodic structure embedded inside. The homogenized transmission conditions govern the interface discontinuity of the acoustic pressure associated with the two halfspaces and the magnitude of the fictitious transversal acoustic velocity. By numerical examples we illustrate this novel approach of modeling the acoustic impedance of perforated interfaces.

  8. ESR observation of optically generated solitons in the quasi-one-dimensional iodo-bridged diplatinum complex Pt2(n-pentylCS2)4I

    Science.gov (United States)

    Tanaka, Hisaaki; Nishiyama, Hideshi; Kuroda, Shin-Ichi; Yamashita, Takami; Mitsumi, Minoru; Toriumi, Koshiro

    2008-07-01

    Light-induced electron spin resonance (LESR) measurements have been performed on a quasi-one-dimensional (Q1D) iodo-bridged diplatinum complex Pt2(n-pentylCS2)4I , where the thermal activation of solitons has been reported in the doubly-degenerate alternate-charge-polarization (ACP) [Pt2+-Pt3+-I--Pt3+-Pt2+] state formed below 210 K. An enhancement of ESR signal has been detected due to the photogeneration of Pt3+ spins below about 30 K, as confirmed through the observed g values of g∥=1.980 and g⊥=2.215 with the external field parallel and perpendicular to the chain axis, respectively. The LESR linewidth is clearly smaller than that of the ESR signal of Curie spins observed under the dark condition, whereas it exhibits uniaxial anisotropy similar to that of the dark ESR due to the anisotropic hyperfine interaction of Pt and iodine nuclear spins. The small LESR linewidth compares well with the motionally-narrowed ESR linewidth of thermally activated solitons at elevated temperatures, indicating that the photogenerated spins are mobile. Furthermore, bimolecular recombination of photogenerated spins has been demonstrated from the excitation power dependence and decay curves of LESR intensity. These LESR features strongly suggest that the mobile spins are photogenerated solitons, which agrees with theoretical predictions.

  9. Sonification of acoustic emission data

    Science.gov (United States)

    Raith, Manuel; Große, Christian

    2014-05-01

    While loading different specimens, acoustic emissions appear due to micro crack formation or friction of already existing crack edges. These acoustic emissions can be recorded using suitable ultrasonic transducers and transient recorders. The analysis of acoustic emissions can be used to investigate the mechanical behavior of different specimens under load. Our working group has undertaken several experiments, monitored with acoustic emission techniques. Different materials such as natural stone, concrete, wood, steel, carbon composites and bone were investigated. Also the experimental setup has been varied. Fire-spalling experiments on ultrahigh performance concrete and pullout experiments on bonded anchors have been carried out. Furthermore uniaxial compression tests on natural stone and animal bone had been conducted. The analysis tools include not only the counting of events but the analysis of full waveforms. Powerful localization algorithms and automatic onset picking techniques (based on Akaikes Information Criterion) were established to handle the huge amount of data. Up to several thousand events were recorded during experiments of a few minutes. More sophisticated techniques like moment tensor inversion have been established on this relatively small scale as well. Problems are related to the amount of data but also to signal-to-noise quality, boundary conditions (reflections) sensor characteristics and unknown and changing Greens functions of the media. Some of the acoustic emissions recorded during these experiments had been transferred into audio range. The transformation into the audio range was done using Matlab. It is the aim of the sonification to establish a tool that is on one hand able to help controlling the experiment in-situ and probably adjust the load parameters according to the number and intensity of the acoustic emissions. On the other hand sonification can help to improve the understanding of acoustic emission techniques for training

  10. Acoustic constituents of prosodic typology

    Science.gov (United States)

    Komatsu, Masahiko

    Different languages sound different, and considerable part of it derives from the typological difference of prosody. Although such difference is often referred to as lexical accent types (stress accent, pitch accent, and tone; e.g. English, Japanese, and Chinese respectively) and rhythm types (stress-, syllable-, and mora-timed rhythms; e.g. English, Spanish, and Japanese respectively), it is unclear whether these types are determined in terms of acoustic properties, The thesis intends to provide a potential basis for the description of prosody in terms of acoustics. It argues for the hypothesis that the source component of the source-filter model (acoustic features) approximately corresponds to prosody (linguistic features) through several experimental-phonetic studies. The study consists of four parts. (1) Preliminary experiment: Perceptual language identification tests were performed using English and Japanese speech samples whose frequency spectral information (i.e. non-source component) is heavily reduced. The results indicated that humans can discriminate languages with such signals. (2) Discussion on the linguistic information that the source component contains: This part constitutes the foundation of the argument of the thesis. Perception tests of consonants with the source signal indicated that the source component carries the information on broad categories of phonemes that contributes to the creation of rhythm. (3) Acoustic analysis: The speech samples of Chinese, English, Japanese, and Spanish, differing in prosodic types, were analyzed. These languages showed difference in acoustic characteristics of the source component. (4) Perceptual experiment: A language identification test for the above four languages was performed using the source signal with its acoustic features parameterized. It revealed that humans can discriminate prosodic types solely with the source features and that the discrimination is easier as acoustic information increases. The

  11. CALCULATION OF ACOUSTIC EFFICIENCY OF PORTABLE ACOUSTIC SCREEN

    Directory of Open Access Journals (Sweden)

    Aleksandr Skvortsov

    2016-03-01

    Full Text Available The research of influence of life environment adverse factors on physical development and health of population is an actual problem of ecology. The aspects of the most actual problems of the modern world, namely environmental industrial noise pollution are considered in the article. Industrial facilities everywhere have noisy equipment. Noise is a significant factors of negative influenceon people and environment. Combined effects of noise and of other physical pollutions on people may cause amplification of their negative impact. If the noise pollution level from the object in a residential area exceeds the permissible levels (MPL, noise protection measures can be initiated. Today, the most common design decisions for noise protection are sound absorbing construction, noise screens and barriers, acousting housings, soundproff cabins. Many of them are popular, others are less known. The article deals with one of the most wide spread means of noise protection – a portable acoustic screen. The aim of the research is to determine the efficiency of portable acoustic screens. It is shown that the installation of such structures can reduce the average value of the sound level. The authors analyzed acoustic screens as device to reduce noise pollution. The authors offer a potable acoustic screen differing from the used easyness, mobility, minimum price and good sound protective properties. Effectiveness, a sound absorption coefficient and sound conductivity coefficient of a portable acoustic screen are evaluated. The descriptions of the algorithm calculations and the combination of technical solutions have practical originality. The results of the research demonstrate the advantages of the proposed solutions for reducing noise levels in the agro-industrial complex.

  12. Determination of reactions between free radicals and selected Chilean wines and transition metals by ESR and UV-vis technique

    Science.gov (United States)

    Espinoza, Mónica; Olea-Azar, Claudio; Speisky, Hernán; Rodríguez, Jorge

    2009-01-01

    Four different types of Chilean wines (Cabernet Sauvignon, Merlot, Carmenere and Syrah) were selected and examined in their free radical scavenging capacities by electron spin resonance (ESR) and spectrophotometric methods. The free radical scavenging properties were evaluated against 2,2-diphenyl-1-picrylhydrazyl (DPPH rad ) radical, 2,6-di- tert-butyl-alpha-(3,5-di- tert-butyl-4-oxo-2,5-cyclohexadien-1-ylidene)- p-tolyloxy (Galvinoxyl) radical and hydroxyl radical (HO rad ). The possible effect on these scavenging properties of added transition metals to these wines was evaluated. Among the wines evaluated, Cabernet Sauvignon was the one with the highest activity against all radicals tested. The presence of added copper or iron to wines resulted in a reduced free radical scavenging capacity for all type of wines studied. The formation of redox inactive complexes between polyphenols of wine and transition metals is the possible cause of this reduction in antioxidant activity.

  13. Electron spin resonance (ESR) study of VO{sup 2+} doped germanium dioxide synthesized via the sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Mendez-Vivar, J.; Arroyo, R. [Univ. Autonoma Metropolitana-Iztapalapa (Mexico). Dept. de Quimica

    1994-12-31

    VOSO{sub 4}{center_dot}3H{sub 2}O was used as doping agent to prepare GeO{sub 2} xerogels, via the sol-gel process. Samples were analyzed by Thermal Gravimetric Analysis (TGA), Differential Thermal Analysis, (DTA), Diffuse reflectance (UV-Vis) spectroscopy and electron spin resonance (ESR). Study of thermally treated samples was performed. VO{sup 2+} were found in V{sub 2}O{sub 5} at 350 C. VO{sup 2+} ions were incorporated in the GeO{sub 2} network after thermal treatment at 700 C. From the results the authors propose that VO{sup 2+} acts as crystal former in these samples.

  14. Morphology of sulfonated polyimide ionomers from ESR spectra of paramagnetic transition metal cations and nitroxide spin probes

    International Nuclear Information System (INIS)

    We present a study of sulfonated polyimide block ionomer membranes (SPIs) in the dry state, and swollen by water, methanol, ethanol, and dioxane. The ionomers are based on a naphthalenic dianhydride, and differ in the ionic exchange capacity and the type of diamine in the hydrophobic block. The ionomers were studied by electron spin resonance (ESR) spectroscopy of the paramagnetic transition metal cations Cu+ and VO2+, and of two nitroxide spin probes. The results indicated the existence of separate hydrophobic and hydrophilic domains in the dry and in the swollen membranes. Water clusters with a diameter + or K+. The irreversible increase of the signal intensity upon heating of the dry membranes above 360 K suggests the formation of reactive intermediates that may be involved in ionomer degradation processes. (author)

  15. ESR study of oxidation product in irradiated α-amino acids: Nitrogen centered π radical in α-glycine

    International Nuclear Information System (INIS)

    The structure of the oxidation product H2N+CH2CO2- in irradiated α-glycine has been studied based on the hyperfine coupling tensors which have been determined at 4.2degreeK by single crystal ESR measurements. It has been found that the radical initially possesses a nearly planar structure at the nitrogen atom with a framework similar to that of the undamaged molecule and then changes its conformation into the form previously found by Sinclair. The principal axes of the nitrogen coupling tensor suggest that the selective proton or hydrogen atom transfer from the NH3+ group takes place across the shortest hydrogen bond forming the radical

  16. The effect of irradiation dose and age of bird on the ESR signal in irradiated chicken drumsticks

    Science.gov (United States)

    Gray, Richard; Stevenson, M. Hilary; Kilpatrick, David J.

    Groups of 20 broiler chickens of the same genetic strain and reared under identical conditions were slaughtered at either 4, 5, 6, 7 or 8 weeks of age. Pairs of drumsticks were removed from each bird and groups were either not irradiated or irradiated at 2.5, 5.0, 7.5 or 10.0 kGy using a cobalt 60 source. Bone samples were excised, fragmented, freeze dried and ground prior to the determination of free radical concentration using electron spin resonance (ESR) spectroscopy. Increasing irradiation dose gave a highly significant increase in free radical concentration whilst for each irradiation dose, bones from younger birds gave significantly lower concentrations compared to those for older birds. Crystallinity coefficient increased linearly with age of bird and this may account in part for the increased signal observed as the birds aged.

  17. DEFORMATION CHARACTERISTICS AND ESR DATING OF ANHUA-XUPU FAULT BELT IN THE XUEFENG MOUNATAINS,HUNAN

    Institute of Scientific and Technical Information of China (English)

    YANG Kuifeng; YANG Kunguang; MA Changqian

    2005-01-01

    Anhua-Xupu fault belt plays a very important role in the formation of Xuefeng Mountains. The fault belt shows an arc-structure extruding towards NW. Fault rocks, microstructures and homogeneous temperature (concentrated around 160°C) of fluid inclusions in the quartz veins shows that the fault belt mainly underwent shallow brittle deformation and the highest-grade dynamic metamorphic rock is mylonitized sericite phyllite. The ESR (Electron Spin Resonance) dating from the quartz veins in the fault rocks shows that the fault belt underwent two intense fluid movement stages at Yanshanian (156.9~136.2Ma, 119.8~90.6Ma); moreover not only the occurrence and microstructures but also the homogeneous temperature of the quartz veins developed in that two stages show obvious diversity,which can prove that there exists the reversion period of Mesozoic extension and compression movement of Xuefeng mountains between these two stages.

  18. Improvement of the LET sensitivity in ESR dosimetry for {gamma}-photons and thermal neutrons through gadolinium addition

    Energy Technology Data Exchange (ETDEWEB)

    Marrale, M. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Unita CNISM, Palermo and Gruppo V Sezione INFN, Catania (Italy)], E-mail: marrale@difter.unipa.it; Brai, M. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Unita CNISM, Palermo and Gruppo V Sezione INFN, Catania (Italy); Gennaro, G.; Triolo, A. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Bartolotta, A. [Dipartimento Farmacochimico Tossicologico e Biologico, Universita di Palermo, Via Archirafi 32, 90123 Palermo (Italy); Unita CNISM, Palermo and Gruppo V Sezione INFN, Catania (Italy)

    2007-07-15

    We investigated the ESR response of new materials, alanine and ammonium tartrate to which gadolinium was added. The addition of gadolinium enhances sensitivity for {sup 60}Co{gamma}-photons because of its high atomic number (Z=64) and an enhancement of sensitivity for thermal neutrons because of its high thermal neutron cross section and high linear energy transfer (LET) secondary particles produced after the reaction with neutrons. In particular, in this paper we analyzed the microwave power saturation properties of dosimeters of alanine and ammonium tartrate with or without gadolinium exposed to different LET beams. The power saturation trends of dosimeters exposed to photons and to thermal neutrons are different. For ammonium tartrate dosimeters the gadolinium addition intensifies significantly these differences and therefore, it improves the ammonium tartrate's ability to discriminate the radiation LET.

  19. SIMULTANEOUS MEASUREMENT OF FREE RADICAL DECAY IN POLYMERIZATION OF MMA INITIATED BY AIBN USING ESR AND ITS KINETIC MODEL

    Institute of Scientific and Technical Information of China (English)

    Ping Xia; Qing-song Hu; Xiao-lan Qian; Xul-in Jiang; De-yue Yan

    2001-01-01

    The kinetics of free radical decay in the polymerization of MMA initiated by AIBN was studied by means of ESR spectroscopy. It was found that the curves of radical decay are strongly associated with the reaction temperature, the initiator concentration and the solvent. In the case of the radical polymerization carried out at high temperature or in solution, the radical concentration first reached a maximum, then declined monotonously with reaction time. It was also found that the greater the amount of initiator or the higher the temperature, the more rapidly the radicals decay. When the bulk polymerization was implemented at a relatively low temperature, the curves of radical decay became more complicated, i.e.,the radical concentration rapidly rose to a maximum, then dropped to a minimum, finally increased again with reaction time.Taking into account the diffusion effect, a semi-empirical equation is suggested to describe the kinetics of propagating radical decay.

  20. Decomposition of gaseous toluene on thermally-excited titanium dioxide and its ESR study under high temperatures

    International Nuclear Information System (INIS)

    Decomposition of gaseous toluene on thermally-excited activated titanium dioxide (TiO2) was investigated using a simple flow system. The decomposition of toluene on the TiO2 bead was 92% at 400 deg. C. The irregular phenomena in the toluene decomposition at around 300 deg. C seemed to be due to the coloration of the TiO2 bead. Electron spin resonance (ESR) measurement at high temperatures was carried out using the heating unit. Since the g-value of the signal was 1.996, the existence of Ti3+ in TiO2 material was confirmed. That is, oxygen vacancy generated by thermally-excitation of TiO2, and the reaction activity of the TiO2 bead for gaseous toluene must be due to spins on the material.

  1. Conformational distributions and hydrogen bonding in gel and frozen lipid bilayers: a high frequency spin-label ESR study.

    Science.gov (United States)

    Dzikovski, Boris; Tipikin, Dmitriy; Freed, Jack

    2012-06-14

    The ESR parameters of PC spin labels in frozen membranes do not simply represent the membrane polarity or water penetration profile. Instead, they show a distribution between hydrogen-bonded (HB) and non-hydrogen-bonded (non-HB) states, which is affected by a number of factors in the membrane composition. Similar to the exclusion of solutes from crystallizing solvents, the pure bulk gel phase excludes nitroxides, forcing acyl chains to take bent conformations. In these conformations, the nitroxide is hydrogen-bonded. Furthermore, upon gradual cooling in the supercooled gel, PC labels undergo slow lateral aggregation, resulting in a broad background signal. However, if the sample is instantly frozen, this background is replaced by the HB component. In membranes with cholesterol, the observed HB/non-HB ratio can best be described by a partition-like equilibrium between nitroxides located in defects of lipid structure within the hydrophobic core and those close to the membrane surface. PMID:22324811

  2. My 65 years in acoustics

    Science.gov (United States)

    Beranek, Leo L.

    2001-05-01

    My entry into acoustics began as research assistant to Professor F. V. Hunt at Harvard University. I received my doctorate in 1940 and directed the Electro-Acoustic Laboratory at Harvard from October 1940 until September 1945. In 1947, I became a tenured associate professor at MIT, and, with Richard H. Bolt, formed the consulting firm Bolt and Beranek, that later included Robert B. Newman, becoming BBN. My most significant contributions before 1970 were design of wedge-lined anechoic chambers, systemization of noise reduction in ventilation systems, design of the world's largest muffler for the testing of supersonic jet engines at NASA's Lewis Laboratory in Cleveland, speech interference level, NC noise criterion curves, heading New York Port Authority's noise study that resulted in mufflers on jet aircraft, and steep aircraft climb procedures, and publishing books titled, Acoustical Measurements, Acoustics, Noise Reduction, Noise and Vibration Control, and Music, Acoustics and Architecture. As President of BBN, I supervised the formation of the group that built and operated the ARPANET (1969), which, when split in two (using TCP/IP protocol) became the INTERNET (1984). Since then, I have written two books on Concert Halls and Opera Houses and have consulted on four concert halls and an opera house.

  3. ESR1 is co-expressed with closely adjacent uncharacterised genes spanning a breast cancer susceptibility locus at 6q25.1.

    Directory of Open Access Journals (Sweden)

    Anita K Dunbier

    2011-04-01

    Full Text Available Approximately 80% of human breast carcinomas present as oestrogen receptor α-positive (ER+ve disease, and ER status is a critical factor in treatment decision-making. Recently, single nucleotide polymorphisms (SNPs in the region immediately upstream of the ER gene (ESR1 on 6q25.1 have been associated with breast cancer risk. Our investigation of factors associated with the level of expression of ESR1 in ER+ve tumours has revealed unexpected associations between genes in this region and ESR1 expression that are important to consider in studies of the genetic causes of breast cancer risk. RNA from tumour biopsies taken from 104 postmenopausal women before and after 2 weeks treatment with an aromatase (oestrogen synthase inhibitor was analyzed on Illumina 48K microarrays. Multiple-testing corrected Spearman correlation revealed that three previously uncharacterized open reading frames (ORFs located immediately upstream of ESR1, C6ORF96, C6ORF97, and C6ORF211 were highly correlated with ESR1 (Rs =  0.67, 0.64, and 0.55 respectively, FDR<1 × 10(-7. Publicly available datasets confirmed this relationship in other groups of ER+ve tumours. DNA copy number changes did not account for the correlations. The correlations were maintained in cultured cells. An ERα antagonist did not affect the ORFs' expression or their correlation with ESR1, suggesting their transcriptional co-activation is not directly mediated by ERα. siRNA inhibition of C6ORF211 suppressed proliferation in MCF7 cells, and C6ORF211 positively correlated with a proliferation metagene in tumours. In contrast, C6ORF97 expression correlated negatively with the metagene and predicted for improved disease-free survival in a tamoxifen-treated published dataset, independently of ESR1. Our observations suggest that some of the biological effects previously attributed to ER could be mediated and/or modified by these co-expressed genes. The co-expression and function of these genes may be

  4. In-situ ESR of Rh/{gamma}-Al{sub 2}O{sub 3} and Rh/ZSM-5

    Energy Technology Data Exchange (ETDEWEB)

    Lakeev, S.G.; Kucherov, A.V.; Shelef, M. [Ford Research Laboratory, Ford Motor Company, Dearborn, MI (United States)

    1998-12-31

    Rhodium supported on {gamma}-Al{sub 2}O{sub 3} is an important component of 3-way automotive catalysts and has been studied by a wide variety of methods including ESR. In the last 15 years Rh-species introduced into zeolites of different types (Y,X,L,A,SAPO) have also been examined by several techniques. However, most of these methods were applied after the specimens were removed from actual reaction conditions and transferred into the respective characterization instruments and the state or behavior of the catalyst in-situ was arrived at indirectly by inference. Also the deactivation processes or the effect of modifiers is seldom, if ever, determined by direct in-situ observations. We have previously devised a method for high-temperature measurement of ESR-active ions under flow conditions and applied it to characterize specimens containing Cu{sup 2+} [10] or Cr{sup 5+} [11]. We have extended this method now to specimens containing Rh{sup 2+}. Here, we summarize the results of a study of the interaction of Rh/{gamma}-Al{sub 2}O{sub 3} and Rh/ZSM-5 with different gases and gas mixtures (NO, NO{sub 2}, CO, propene, O{sub 2}, H{sub 2}O) at 120-573 K. The amount of Rh{sup 2+} present in the samples is evaluated quantitatively. The effect of copper and lanthanide addition on the stabilization of Rh{sup 2+} by the zeolitic matrix was also investigated. 21 refs.

  5. An apparatus for pulsed ESR and DNP experiments using optically excited triplet states down to liquid helium temperatures

    Science.gov (United States)

    Eichhorn, T. R.; Haag, M.; van den Brandt, B.; Hautle, P.; Wenckebach, W. Th.; Jannin, S.; van der Klink, J. J.; Comment, A.

    2013-09-01

    In standard Dynamic Nuclear Polarization (DNP) electron spins are polarized at low temperatures in a strong magnetic field and this polarization is transferred to the nuclear spins by means of a microwave field. To obtain high nuclear polarizations cryogenic equipment reaching temperatures of 1 K or below and superconducting magnets delivering several Tesla are required. This equipment strongly limits applications in nuclear and particle physics where beams of particles interact with the polarized nuclei, as well as in neutron scattering science. The problem can be solved using short-lived optically excited triplet states delivering the electron spin. The spin is polarized in the optical excitation process and both the cryogenic equipment and magnet can be simplified significantly. A versatile apparatus is described that allows to perform pulsed dynamic nuclear polarization experiments at X-band using short-lived optically excited triplet sates. The efficient 4He flow cryostat that cools the sample to temperatures between 4 K and 300 K has an optical access with a coupling stage for a fiber transporting the light from a dedicated laser system. It is further designed to be operated on a neutron beam. A combined pulse ESR/DNP spectrometer has been developed to observe and characterize the triplet states and to perform pulse DNP experiments. The ESR probe is based on a dielectric ring resonator of 7 mm inner diameter that can accommodate cubic samples of 5 mm length needed for neutron experiments. NMR measurements can be performed during DNP with a coil integrated in the cavity. With the presented apparatus a proton polarization of 0.5 has been achieved at 0.3 T.

  6. ESR evidence for in vivo formation of free radicals in tissue of mice exposed to single-walled carbon nanotubes.

    Science.gov (United States)

    Shvedova, A A; Kisin, E R; Murray, A R; Mouithys-Mickalad, A; Stadler, K; Mason, R P; Kadiiska, M

    2014-08-01

    Nanomaterials are being utilized in an increasing variety of manufactured goods. Because of their unique physicochemical, electrical, mechanical, and thermal properties, single-walled carbon nanotubes (SWCNTs) have found numerous applications in the electronics, aerospace, chemical, polymer, and pharmaceutical industries. Previously, we have reported that pharyngeal exposure of C57BL/6 mice to SWCNTs caused dose-dependent formation of granulomatous bronchial interstitial pneumonia, fibrosis, oxidative stress, acute inflammatory/cytokine responses, and a decrease in pulmonary function. In the current study, we used electron spin resonance (ESR) to directly assess whether exposure to respirable SWCNTs caused formation of free radicals in the lungs and in two distant organs, the heart and liver. Here we report that exposure to partially purified SWCNTs (HiPco technique, Carbon Nanotechnologies, Inc., Houston, TX, USA) resulted in the augmentation of oxidative stress as evidenced by ESR detection of α-(4-pyridyl-1-oxide)-N-tert-butylnitrone spin-trapped carbon-centered lipid-derived radicals recorded shortly after the treatment. This was accompanied by a significant depletion of antioxidants and elevated biomarkers of inflammation presented by recruitment of inflammatory cells and an increase in proinflammatory cytokines in the lungs, as well as development of multifocal granulomatous pneumonia, interstitial fibrosis, and suppressed pulmonary function. Moreover, pulmonary exposure to SWCNTs also caused the formation of carbon-centered lipid-derived radicals in the heart and liver at later time points (day 7 postexposure). Additionally, SWCNTs induced a significant accumulation of oxidatively modified proteins, increase in lipid peroxidation products, depletion of antioxidants, and inflammatory response in both the heart and the liver. Furthermore, the iron chelator deferoxamine noticeably reduced lung inflammation and oxidative stress, indicating an important role for

  7. Common genetic variation in the Estrogen Receptor Beta (ESR2 gene and osteoarthritis: results of a meta-analysis

    Directory of Open Access Journals (Sweden)

    Rivadeneira Fernando

    2010-11-01

    Full Text Available Abstract Background The objective of this study was to examine the relationship between common genetic variation of the ESR2 gene and osteoarthritis. Methods In the discovery study, the Rotterdam Study-I, 7 single nucleotide polymorphisms (SNPs were genotyped and tested for association with hip (284 cases, 2772 controls, knee (665 cases, 2075 controls, and hand OA (874 cases, 2184 controls using an additive model. In the replication stage one SNP (rs1256031 was tested in an additional 2080 hip, 1318 knee and 557 hand OA cases and 4001, 2631 and 1699 controls respectively. Fixed- and random-effects meta-analyses were performed over the complete dataset including 2364 hip, 1983 knee and 1431 hand OA cases and approximately 6000 controls. Results The C allele of rs1256031 was associated with a 36% increased odds of hip OA in women of the Rotterdam Study-I (OR 1.36, 95% CI 1.08-1.70, p = 0.009. Haplotype analysis and analysis of knee- and hand OA did not give additional information. With the replication studies, the meta-analysis did not show a significant effect of this SNP on hip OA in the total population (OR 1.06, 95% CI 0.99-1.15, p = 0.10. Stratification according to gender did not change the results. In this study, we had 80% power to detect an odds ratio of at least 1.14 for hip OA (α = 0.05. Conclusion This study showed that common genetic variation in the ESR2 gene is not likely to influence the risk of osteoarthritis with effects smaller than a 13% increase.

  8. Effect of estrogen receptor-alpha (ESR1 gene polymorphism on high density lipoprotein levels in response to hormone replacement therapy

    Directory of Open Access Journals (Sweden)

    N.C. Nogueira-de-Souza

    2009-12-01

    Full Text Available Studies have shown that estrogen replacement therapy and estrogen plus progestin replacement therapy alter serum levels of total, LDL and HDL cholesterol levels. However, HDL cholesterol levels in women vary considerably in response to hormone replacement therapy (HRT. A significant portion of the variability of these levels has been attributed to genetic factors. Therefore, we investigated the influence of estrogen receptor-alpha (ESR1 gene polymorphisms on HDL levels in response to postmenopausal HRT. We performed a prospective cohort study on 54 postmenopausal women who had not used HRT before the study and had no significant general medical illness. HRT consisted of conjugated equine estrogen and medroxyprogesterone acetate continuously for 1 year. The lipoprotein levels were measured from blood samples taken before the start of therapy and after 1 year of HRT. ESR1 polymorphism (MspI C>T, HaeIII C>T, PvuII C>T, and XbaI A>G frequencies were assayed by restriction fragment length polymorphism. A general linear model was used to describe the relationships between HDL levels and genotypes after adjusting for age. A significant increase in HDL levels was observed after HRT (P = 0.029. Women with the ESR1 PvuII TT genotype showed a statistically significant increase in HDL levels after HRT (P = 0.032. No association was found between other ESR1 polymorphisms and HDL levels. According to our results, the ESR1 PvuII TT genotype was associated with increased levels of HDL after 1 year of HRT.

  9. Acoustic metasurface with hybrid resonances.

    Science.gov (United States)

    Ma, Guancong; Yang, Min; Xiao, Songwen; Yang, Zhiyu; Sheng, Ping

    2014-09-01

    An impedance-matched surface has the property that an incident wave generates no reflection. Here we demonstrate that by using a simple construction, an acoustically reflecting surface can acquire hybrid resonances and becomes impedance-matched to airborne sound at tunable frequencies, such that no reflection is generated. Each resonant cell of the metasurface is deep-subwavelength in all its spatial dimensions, with its thickness less than the peak absorption wavelength by two orders of magnitude. As there can be no transmission, the impedance-matched acoustic wave is hence either completely absorbed at one or multiple frequencies, or converted into other form(s) of energy, such as an electrical current. A high acoustic-electrical energy conversion efficiency of 23% is achieved. PMID:24880731

  10. Acoustic Localization with Infrasonic Signals

    Science.gov (United States)

    Threatt, Arnesha; Elbing, Brian

    2015-11-01

    Numerous geophysical and anthropogenic events emit infrasonic frequencies (wind turbines and tornadoes. These sounds, which cannot be heard by the human ear, can be detected from large distances (in excess of 100 miles) due to low frequency acoustic signals having a very low decay rate in the atmosphere. Thus infrasound could be used for long-range, passive monitoring and detection of these events. An array of microphones separated by known distances can be used to locate a given source, which is known as acoustic localization. However, acoustic localization with infrasound is particularly challenging due to contamination from other signals, sensitivity to wind noise and producing a trusted source for system development. The objective of the current work is to create an infrasonic source using a propane torch wand or a subwoofer and locate the source using multiple infrasonic microphones. This presentation will present preliminary results from various microphone configurations used to locate the source.

  11. Acoustic multivariate condition monitoring - AMCM

    Energy Technology Data Exchange (ETDEWEB)

    Rosenhave, P.E. [Vestfold College, Maritime Dept., Toensberg (Norway)

    1997-12-31

    In Norway, Vestfold College, Maritime Department presents new opportunities for non-invasive, on- or off-line acoustic monitoring of rotating machinery such as off-shore pumps and diesel engines. New developments within acoustic sensor technology coupled with chemometric data analysis of complex signals now allow condition monitoring of hitherto unavailable flexibility and diagnostic specificity. Chemometrics paired with existing knowledge yields a new and powerful tool for condition monitoring. By the use of multivariate techniques and acoustics it is possible to quantify wear and tear as well as predict the performance of working components in complex machinery. This presentation describes the AMCM method and one result of a feasibility study conducted onboard the LPG/C `Norgas Mariner` owned by Norwegian Gas Carriers as (NGC), Oslo. (orig.) 6 refs.

  12. Acoustic Communication for Medical Nanorobots

    CERN Document Server

    Hogg, Tad

    2012-01-01

    Communication among microscopic robots (nanorobots) can coordinate their activities for biomedical tasks. The feasibility of in vivo ultrasonic communication is evaluated for micron-size robots broadcasting into various types of tissues. Frequencies between 10MHz and 300MHz give the best tradeoff between efficient acoustic generation and attenuation for communication over distances of about 100 microns. Based on these results, we find power available from ambient oxygen and glucose in the bloodstream can readily support communication rates up to 10,000 bits/second between micron-sized robots. We discuss techniques, such as directional acoustic beams, that can increase this rate. The acoustic pressure fields enabling this communication are unlikely to damage nearby tissue, and short bursts at considerably higher power could be of therapeutic use.

  13. On Architectural Acoustics Design using Computer Simulation

    DEFF Research Database (Denmark)

    Schmidt, Anne Marie Due; Kirkegaard, Poul Henning

    2004-01-01

    The acoustical quality of a given building, or space within the building, is highly dependent on the architectural design. Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in the architectural acoustic and the emergence of potent...... room acoustic simulation programs it is now possible to subjectively analyze and evaluate acoustic properties prior to the actual construction of a facility. With the right tools applied, the acoustic design can become an integrated part of the architectural design process. The aim of the present paper...... is to investigate the field of application an acoustic simulation program can have during an architectural acoustics design process. A case study is carried out in order to represent the iterative working process of an architect. The working process is divided into five phases and represented by typical results...

  14. Acoustojet: acoustic analogue of photonic jet phenomenon

    CERN Document Server

    Minin, Igor V

    2016-01-01

    It has been demonstrated for the first time that an existence of acoustic analogue of photonic jet phenomenon, called acoustojet, providing for subwavelength localization of acoustic field in the shadow area of arbitrary 3D penetrable mesoscale particle, is possible.

  15. Golden Gate and Pt. Reyes Acoustic Detections

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains detections of acoustic tagged fish from two general locations: Golden Gate (east and west line) and Pt. Reyes. Several Vemco 69khz acoustic...

  16. Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis

    Science.gov (United States)

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis On this page: ... more information about vestibular schwannomas? What is a vestibular schwannoma (acoustic neuroma)? Inner ear with vestibular schwannoma ( ...

  17. On the Synchronization of Acoustic Gravity Waves

    Science.gov (United States)

    Lonngren, Karl E.; Bai, Er-Wei

    Using the model proposed by Stenflo, we demonstrate that acoustic gravity waves found in one region of space can be synchronized with acoustic gravity waves found in another region of space using techniques from modern control theory.

  18. Acoustic network event classification using swarm optimization

    Science.gov (United States)

    Burman, Jerry

    2013-05-01

    Classifying acoustic signals detected by distributed sensor networks is a difficult problem due to the wide variations that can occur in the transmission of terrestrial, subterranean, seismic and aerial events. An acoustic event classifier was developed that uses particle swarm optimization to perform a flexible time correlation of a sensed acoustic signature to reference data. In order to mitigate the effects from interference such as multipath, the classifier fuses signatures from multiple sensors to form a composite sensed acoustic signature and then automatically matches the composite signature with reference data. The approach can classify all types of acoustic events but is particularly well suited to explosive events such as gun shots, mortar blasts and improvised explosive devices that produce an acoustic signature having a shock wave component that is aperiodic and non-linear. The classifier was applied to field data and yielded excellent results in terms of reconstructing degraded acoustic signatures from multiple sensors and in classifying disparate acoustic events.

  19. CT findings of acoustic neuroma

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Do Choul; Lee, Jae Mun; Shinn, Kyung Sub; Bahk, Yong Whee [Catholic Univ., Seoul (Korea, Republic of)

    1987-10-15

    Computed Tomography (CT) is very accurate in evaluating the location, size, shape and extension of acoustic neuroma. We analysed CT findings of 23 acoustic neuromas seen at Department of Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College during the period of from January 1981 to June 1987. 1. Five (22%) were men and 18 (78%) were women with the high incidence occurring in the 4th and 5th decades. 2. Twenty two cases were diagnosed satisfactorily by CT examinations which included axial, coronal and reconstruction images. One with the smallest dimension of 8 mm in diameter could not be detected by the conventional CT scan. But is could be seen after metrizamide cisternography. mean size of the tumor masses was estimated 3.6 cm in diameter. 3. The shape of the tumor was oval in 50%, round in 27% and lobulated in 23%. The masses were presented as hypodense in 50%, isodense in 32% and hyperdense in 18%. All tumors were extended from the internal acoustic and toward the cerebellopontine angle. The internal acoustic canal was widened in 77%. Hydrocephalus was associated in 45%. Widening of cerebellopontine angle cistern was noted in 50%. 4. After contrast infusion the tumors were enhanced markedly in 45%, moderately in 32% and mildly in 23%. The enhanced pattern was homogeneous in 41%, mixed in 41% and rim in 18%. The margin of the tumors was sharply defined in 82%. The tumors were attached to the petrous bone with acute angle in 73%. Cystic change within the tumor was found in 27%. The peritumoral edema was noted in 45%. In conclusion, CT is of most effective modalities to evaluate size, shape, extent and internal architecture of acoustic neuroma as well as relationship with adjacent anatomic structures including the internal acoustic canal.

  20. Acoustically-Induced Electrical Signals

    Science.gov (United States)

    Brown, S. R.

    2014-12-01

    We have observed electrical signals excited by and moving along with an acoustic pulse propagating in a sandstone sample. Using resonance we are now studying the characteristics of this acousto-electric signal and determining its origin and the controlling physical parameters. Four rock samples with a range of porosities, permeabilities, and mineralogies were chosen: Berea, Boise, and Colton sandstones and Austin Chalk. Pore water salinity was varied from deionized water to sea water. Ag-AgCl electrodes were attached to the sample and were interfaced to a 4-wire electrical resistivity system. Under computer control, the acoustic signals were excited and the electrical response was recorded. We see strong acoustically-induced electrical signals in all samples, with the magnitude of the effect for each rock getting stronger as we move from the 1st to the 3rd harmonics in resonance. Given a particular fluid salinity, each rock has its own distinct sensitivity in the induced electrical effect. For example at the 2nd harmonic, Berea Sandstone produces the largest electrical signal per acoustic power input even though Austin Chalk and Boise Sandstone tend to resonate with much larger amplitudes at the same harmonic. Two effects are potentially responsible for this acoustically-induced electrical response: one the co-seismic seismo-electric effect and the other a strain-induced resistivity change known as the acousto-electric effect. We have designed experimental tests to separate these mechanisms. The tests show that the seismo-electric effect is dominant in our studies. We note that these experiments are in a fluid viscosity dominated seismo-electric regime, leading to a simple interpretation of the signals where the electric potential developed is proportional to the local acceleration of the rock. Toward a test of this theory we have measured the local time-varying acoustic strain in our samples using a laser vibrometer.

  1. Absorption boundary conditions for geomertical acoustics

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2012-01-01

    Defining accurate acoustical boundary conditions is of crucial importance for room acoustic simulations. In predicting sound fields using phased geometrical acoustics methods, the absorption coefficients or surface impedances of the boundary surfaces can be used, but no guideline has been developed...... solutions. Two rectangular rooms with uniform and non-uniform absorption distributions are tested. It is concluded that the impedance and random incidence absorption boundary conditions produce reasonable results with some exceptions at low frequencies for acoustically soft materials....

  2. Acoustic concerns related to multi cultural societies

    OpenAIRE

    Gade, Anders Christian

    2001-01-01

    Immigration has increased cultural diversity in western societies. The process of integrating immigrants into their host countries can be smoothed if acousticians learn to recognize (1) the acoustic traditions of immigrant cultures and (2) the specific acoustic needs of the new society members. Two related projects are discussed. The ``Cahrisma'' project (Conservation of Acoustical Heritage by the Revival and Identification of the Sinan's Mosque Acoustics) is sponsored by the European Commiss...

  3. Acoustic design by topology optimization

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard; Jensen, Jakob Søndergaard; Sigmund, Ole

    2008-01-01

    To bring down noise levels in human surroundings is an important issue and a method to reduce noise by means of topology optimization is presented here. The acoustic field is modeled by Helmholtz equation and the topology optimization method is based on continuous material interpolation functions...... in the density and bulk modulus. The objective function is the squared sound pressure amplitude. First, room acoustic problems are considered and it is shown that the sound level can be reduced in a certain part of the room by an optimized distribution of reflecting material in a design domain along the ceiling...

  4. Physical foundations of technical acoustics

    CERN Document Server

    Malecki, I

    1969-01-01

    Physical Foundations of Technical Acoustics discusses theoretical foundations of acoustical engineering. It is not so much a technical compendium as a systematic statement of physical laws so conceived that technologists might find in it all the information they need to become acquainted with the physical meaning and mathematical expression of phenomena they encounter in their work. To facilitate the acquirement of notions, which lie beyond a layman's grasp, the plan of narration adopted consists in beginning with the simplest idealized cases and then gradually moving on to the truest possibl

  5. Acoustic characterization of rehabilitated cloisters

    OpenAIRE

    A. P. O. Carvalho; S. R. C. Vilela

    2008-01-01

    This paper presents the results of field measurements in eight rehabilitated cloisters of old monasteries in Portugal (length: 20 to 35 m and height: 3.3 to 6.3 m) regarding their acoustic behavior to two objective parameters: RT and RASTI. The goal is to characterize the acoustic effect of the rehabilitation done on theses spaces to adapt them to new uses. All these cloisters had recently their galleries#8217; openings to the central yard closed with glass panels. Simple formulas were obtain...

  6. Acoustic Test Characterization of Melamine Foam for Usage in NASA's Payload Fairing Acoustic Attenuation Systems

    Science.gov (United States)

    Hughes, William O.; McNelis, Anne M.; McNelis, Mark E.

    2014-01-01

    The external acoustic liftoff levels predicted for NASA's future heavy lift launch vehicles are expected to be significantly higher than the environment created by today's commercial launch vehicles. This creates a need to develop an improved acoustic attenuation system for future NASA payload fairings. NASA Glenn Research Center initiated an acoustic test series to characterize the acoustic performance of melamine foam, with and without various acoustic enhancements. This testing was denoted as NEMFAT, which stands for NESC Enhanced Melamine Foam Acoustic Test, and is the subject of this paper. Both absorption and transmission loss testing of numerous foam configurations were performed at the Riverbank Acoustical Laboratory in July 2013. The NEMFAT test data provides an initial acoustic characterization and database of melamine foam for NASA. Because of its acoustic performance and lighter mass relative to fiberglass blankets, melamine foam is being strongly considered for use in the acoustic attenuation systems of NASA's future launch vehicles.

  7. Calculating room acoustic parameters from pseudo-impulsive acoustic sources

    Science.gov (United States)

    San Martin, Maria L.; Vela, Antonio; San Martin, Ricardo; Arana, Miguel A.

    2002-11-01

    The impulse response function provides complete information to predict the acoustic response of a room to an acoustic input of arbitrary characteristics. At this job study, small explosions of firecrackers are proposed to be used as pseudo-impulsive acoustics sources to determine some acoustic parameters of a room such as reverberation time, definition, and clarity, comparing these results to those obtained with other techniques. A previous characterization of these sources allows us to state that they can be used for this purpose because they are, in practice, omnidirectional, their temporary pattern is highly repetitive and their spectral power is, as well, repetitive and with enough power in octave bands from 125 Hz to 8 kHz. If the linear time-invariant system impulse response h(t) is known, output signal s(t) regarding any arbitrary signal s(t) can be obtained. For our pseudo-impulsive sources, the output signal s(t) has been taken as impulse response h(t). Using the integrated impulse response method suggested by Schroeder, it has been stated that both the mean values and standard deviations for some parameters are practically identical to results obtained with other usual techniques. (To be presented in Spanish.)

  8. Design of acoustic devices by topology optimization

    DEFF Research Database (Denmark)

    Sigmund, Ole; Jensen, Jakob Søndergaard

    2003-01-01

    The goal of this study is to design and optimize structures and devices that are subjected to acoustic waves. Examples are acoustic lenses, sound walls, waveguides and loud speakers. We formulate the design problem as a topology optimization problem, i.e. distribute material in a design domain...... such that the acoustic response is optimized....

  9. Aero-acoustic Computations of Wind Turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Michelsen, Jess; Sørensen, Jens Nørkær

    2002-01-01

    A numerical algorithm for acoustic noise generation is extended to 3D flows. The approach involves two parts comprising a viscous incompressible flow part and an inviscid acoustic part. In order to simulate noise generated from a wind turbine, the incompressible and acoustic equations are written...

  10. Predicting and auralizing acoustics in classrooms

    DEFF Research Database (Denmark)

    Christensen, Claus Lynge

    2005-01-01

    Although classrooms have fairly simple geometries, this type of room is known to cause problems when trying to predict their acoustics using room acoustics computer modeling. Some typical features from a room acoustics point of view are: Parallel walls, low ceilings (the rooms are flat), uneven...

  11. Optical measurement of acoustic radiation pressure of the near-field acoustic levitation through transparent object

    CERN Document Server

    Nakamura, Satoshi; Sasao, Yasuhiro; Katsura, Kogure; Naoki, Kondo

    2013-01-01

    It is known that macroscopic objects can be levitated for few to several hundred micrometers by near-field acoustic field and this phenomenon is called near-field acoustic levitation (NFAL). Although there are various experiments conducted to measure integrated acoustic pressure on the object surface, up to now there was no direct method to measure pressure distribution. In this study we measured the acoustic radiation pressure of the near-field acoustic levitation via pressure-sensitive paint.

  12. 雌激素受体基因ESR1多态性与乳腺癌易感性的关系%Association between ESR1 gene polymorphisms and breast cancer risk

    Institute of Scientific and Technical Information of China (English)

    张凤春; 徐迎春; 王红霞; 唐雷; 马越

    2011-01-01

    目的:研究雌激素受体α(ESR1)基因单核苷酸多态性(SNPs)与乳腺癌易感性的关系.方法:运用聚合酶链反应(PCR)和限制性片段长度多态性(RFLP)分析的方法检测193例中国汉族女性乳腺癌患者和71名正常女性对照者ESR1基因上rs11155816位点的基因型,以SPSS 11.0软件卡方检验处理数据.结果:rs11155816位点等位基因频率符合Hardy-Weinberg遗传平衡定律.rs11155816位点的等位基因及基因型与患者肿瘤位置及是否存在远处转移相关,差异有显著性(P<0.05);与年龄、大小、组织学类型、受体表达无关.rs11155816位点等位基因及基因型频率在乳腺癌人群与正常对照者间分布差异有显著性,乳腺癌人群中等位基因A频率高于正常人群(23.8%比15.5%,P<0.05).结论:rs11155816位点基因的多态性与乳腺癌患者的肿瘤位置和远处转移相关,等位基因A携带者乳腺癌发病风险较高.%Objective : To study the association between single nucleotide polymorphisms( SNPs ) in the estrogen receptor alpha gene( ESR1 ) with breast cancer risk and different tumor clinical pathological characteristics. Methods : We evaluated the association of SNP rs11155816 genopype with breast cancer risk among 193 cases and 71 controls in a population - based , case - control study by PCR - RFLP based methods. SPSS 11. 0 software was employed for data analysis. Results : The allele frequency of rs11155816 meeted Hardy - Weinberg equilibrium. The allele and genotype frequency of rs11155816 were positively associated with tumor site of patients, metastasis and stage of tumors( P < 0. 05 ),but no significant association between polymorphism and age , size, tissue type and hormonal recepter status was found. The distrihution of rs11155816 genotype was significantly different between patients and normal people . The frequency of A allele in breast cancer patients was higher than that in healthy controls ( 23 . 8 % vs 15. 5% , P < 0

  13. Acoustics SIMOPS: managing the unnecessary

    Energy Technology Data Exchange (ETDEWEB)

    Hanton, Samuel John [Nautronix Marine Technology Solutions, Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Time is money, and offshore operations are expensive. The desire therefore, is to increase efficiency through the condensing of schedules. This inevitably leads to SIMOPS of some degree, and this paper discusses SIMOPS along with, more specifically, the challenges they provide to acoustic positioning. (author)

  14. Topology optimization for acoustic problems

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard

    2006-01-01

    In this paper a method to control acoustic properties in a room with topology optimization is presented. It is shown how the squared sound pressure amplitude in a certain part of a room can be minimized by distribution of material in a design domain along the ceiling in 2D and 3D. Nice 0-1 designs...

  15. Acoustics in the Martian Atmosphere

    Science.gov (United States)

    Williams, J.-P.

    2000-10-01

    With the advent of the first attempt to deliver an acoustic microphone to the Martian surface aboard the failed Mars Polar Lander, there has been growing interests in the development of acoustic sensors to compliment scientific payloads on future spacecraft. Terrestrial scientist have been very successful in using infrasound (sound at frequencies below human detection, detect and monitor atmospheric phenomena related to weather, tornadoes, mountain waves, microbaroms, ionospheric and auroral disturbances, and meteror/fireballs, as well as anthropogenic sources such as aircraft and nuclear explosions. Sounds on Mars at the audible frequencies (20 Hz to 20 kHz) will be severely attenuated due to viscous relaxation and thermal diffusion (collectively referred to as classical attenuation) which will be much more severe in the colder, less dense Martian atmosphere. Molecular relaxation of carbon dioxide will also contribute to the sound absorption in the lower audible frequencies. Since classical attenuation increases as a function of the frequency squared, at low infrasonic frequencies ( < 10 Hz), classical attenuation becomes less significant and sound absorption in the Martian atmosphere becomes more similar to that of the terrestrial atmosphere for the same frequencies. At these longer wavelengths, geometric spreading will dominate as the source of attenuation as the acoustic energy is spread out over an ever increasing spherical wave front. This implies that infrasound (10 to 0.01 Hz) will be a useful frequency range for future acoustic sensors developed for scientific payloads delivered to the Martian surface.

  16. Longitudinal bulk acoustic mass sensor

    DEFF Research Database (Denmark)

    Hales, Jan Harry; Teva, Jordi; Boisen, Anja;

    2009-01-01

    A polycrystalline silicon longitudinal bulk acoustic cantilever is fabricated and operated in air at 51 MHz. A mass sensitivity of 100 Hz/fg (1 fg=10(-15) g) is obtained from the preliminary experiments where a minute mass is deposited on the device by means of focused ion beam. The total noise i...

  17. Satellite and acoustic tracking device

    KAUST Repository

    Berumen, Michael L.

    2014-02-20

    The present invention relates a method and device for tracking movements of marine animals or objects in large bodies of water and across significant distances. The method and device can track an acoustic transmitter attached to an animal or object beneath the ocean surface by employing an unmanned surface vessel equipped with a hydrophone array and GPS receiver.

  18. SES and Acoustics at GSFC

    Science.gov (United States)

    Hogue, Patrick

    2008-01-01

    This paper presents air and surface cleanliness characterization of the acoustics test facility and large (SES) thermal vacuum chamber at Goddard Space flight Center in Greenbelt, MD during the New Horizons Pluto probe program. It is shown that slow back-fill of the SES chamber is necessary to prevent excessive particle redistribution.

  19. Acoustic counter-sniper system

    Science.gov (United States)

    Duckworth, Gregory L.; Gilbert, Douglas C.; Barger, James E.

    1997-02-01

    BBN has developed, tested, and fielded pre-production versions of a versatile acoustics-based counter-sniper system. This system was developed by BBN for the DARPA Tactical Technology Office to provide a low cost and accurate sniper detection and localization system. The system uses observations of the shock wave from supersonic bullets to estimate the bullet trajectory, Mach number, and caliber. If muzzle blast observations are also available from unsilenced weapons, the exact sniper location along the trajectory is also estimated. A newly developed and very accurate model of the bullet ballistics and acoustic radiation is used which includes bullet deceleration. This allows the use of very flexible acoustic sensor types and placements, since the system can model the bullet's flight, and hence the acoustic observations, over a wide area very accurately. System sensor configurations can be as simple as two small four element tetrahedral microphone arrays on either side of the area to be protected, or six omnidirectional microphones spread over the area to be monitored. Increased performance can be obtained by expanding the sensor field in size or density, and the system software is easily reconfigured to accommodate this at deployment time. Sensor nodes can be added using wireless network telemetry or hardwired cables to the command node processing and display computer. The system has been field tested in three government sponsored tests in both rural and simulated urban environments at the Camp Pendleton MOUT facility. Performance was characterized during these tests for various shot geometries and bullet speeds and calibers.

  20. ガラス線量計及びESR ドシメトリーを用いるγ線照射装置の時間依存検量線作成

    OpenAIRE

    中島, 暉; 長田, 栄二; 松田, 恵美子; 松田, 達郎

    2010-01-01

    Time-dependent calibration curve for the γ-ray irradiator was prepared using radiophoto -luminescence (RDPL) and ESR dosimetry. In RDPL measurement, the radiation dose was linearly increased until 38 Gy. However, above 38 Gy, it deviated upward. The ESR signal intensity of γ-irradiated L-α-alanine indicated linear in the range from 0 to 500 Gy. Though ESR signal intensity of L-α-alanine was saturated with the microwave power, the linearity of the calibration curve was reserved at any microwav...