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Sample records for calorimetre electromagnetique du

  1. Quantification du champ electromagnetique et description quantique de la generation du second harmonique a l'interieur d'une microcavite

    NASA Astrophysics Data System (ADS)

    Collette, Marc

    L'existence de particules virtuelles qui surgissent spontanement du vide pour disparaitre tres peu de temps apres leur apparition (les fluctuations du vide) trouve son origine dans le principe d'incertitude de Heisenberg. Par ailleurs, on sait que le phenomene de resonance par confinement explique l'amplification de l'intensite lumineuse a l'interieur d'une cavite ouverte aux frequences de resonances de celle-ci. C'est pourquoi le taux d'apparition des photons virtuels au sein des modes propres d'une cavite est lui aussi amplifie par le resonateur. Mathematiquement, cet effet quantique est decrit par l'existence d'un commutateur " anomal " entre les operateurs d'annihilation et de creation des photons. Nous decrivons les consequences de ce commutateur sur la generation du second harmonique optique (GSH), un processus photonique ou, dans un materiau optiquement non lineaire, deux photons de meme energie fusionnent pour n'en former qu'un seul. On commence ce travail avec un traitement complet et original sur la quantification du champ electromagnetique. On montre ensuite que les fluctuations du vide stimulent le signal de la GSH a l'interieur du milieu confine. Cependant, on constate aussi que les fluctuations du vide jouent le role d'un inhibiteur au declenchement du processus, c'est-a-dire que le seuil de la GSH augmente (il est superieur au seuil minimal de deux photons seulement). En conclusion, les mecanismes intimes de certains processus optiques non lineaires doivent etre reconsideres lorsqu'ils surviennent en presence d'un confinement electromagnetique.

  2. Device for calorimetric measurement

    DOEpatents

    King, William P; Lee, Jungchul

    2015-01-13

    In one aspect, provided herein is a single crystal silicon microcalorimeter, for example useful for high temperature operation and long-term stability of calorimetric measurements. Microcalorimeters described herein include microcalorimeter embodiments having a suspended structure and comprising single crystal silicon. Also provided herein are methods for making calorimetric measurements, for example, on small quantities of materials or for determining the energy content of combustible material having an unknown composition.

  3. Calorimetric gas sensor

    DOEpatents

    Ricco, A.J.; Hughes, R.C.; Smith, J.H.; Moreno, D.J.; Manginell, R.P.; Senturia, S.D.; Huber, R.J.

    1998-11-10

    A combustible gas sensor is described that uses a resistively heated, noble metal-coated, micromachined polycrystalline Si filament to calorimetrically detect the presence and concentration of combustible gases. The filaments tested to date are 2 {micro}m thick {times} 10{micro}m wide {times} 100, 250, 500, or 1000 {micro}m-long polycrystalline Si; some are overcoated with a 0.25 {micro}m-thick protective CVD Si{sub 3}N{sub 4} layer. A thin catalytic Pt film was deposited by CVD from the precursor Pt(acac){sub 2} onto microfilaments resistively heated to approximately 500 C; Pt deposits only on the hot filament. Using a constant-resistance-mode feedback circuit, Pt-coated filaments operating at ca. 300 C (35 mW input power) respond linearly, in terms of the change in supply current required to maintain constant resistance (temperature), to H{sub 2} concentrations between 100 ppm and 1% in an 80/20 N{sub 2}/O{sub 2} mixture. Other catalytic materials can also be used. 11 figs.

  4. Calorimetric gas sensor

    DOEpatents

    Ricco, Antonio J.; Hughes, Robert C.; Smith, James H.; Moreno, Daniel J.; Manginell, Ronald P.; Senturia, Stephen D.; Huber, Robert J.

    1998-01-01

    A combustible gas sensor that uses a resistively heated, noble metal-coated, micromachined polycrystalline Si filament to calorimetrically detect the presence and concentration of combustible gases. The filaments tested to date are 2 .mu.m thick.times.10 .mu.m wide.times.100, 250, 500, or 1000 .mu.m-long polycrystalline Si; some are overcoated with a 0.25 .mu.m-thick protective CVD Si.sub.3 N.sub.4 layer. A thin catalytic Pt film was deposited by CVD from the precursor Pt(acac).sub.2 onto microfilaments resistively heated to approximately 500.degree. C.; Pt deposits only on the hot filament. Using a constant-resistance-mode feedback circuit, Pt-coated filaments operating at ca. 300.degree. C. (35 mW input power) respond linearly, in terms of the change in supply current required to maintain constant resistance (temperature), to H.sub.2 concentrations between 100 ppm and 1% in an 80/20 N.sub.2 /O.sub.2 mixture. Other catalytic materials can also be used.

  5. Calorimetric thermobarometry of experimentally shocked quartz

    NASA Technical Reports Server (NTRS)

    Ocker, Katherine D.; Gooding, James L.; Hoerz, Friedrich

    1994-01-01

    Structural damage in experimentally shock-metamorphosed, granular quartz is quantitatively measurable by differential scanning calorimetry (DSC). Shock-induced loss of crystallinity is witnessed by disappearance of the alpha/beta phase transformation and evolution of a broad endoenthalpic strain peak at 650-900 K. The strain-energy peak grows rapidly at less than 10 GPa but declines with increasing shock pressure; it approaches zero at 32 GPa where vitrification is extensive. Effects of grain size and post-shock thermal history must be better understood before calorimetric thermobarometry of naturally shocked samples becomes possible.

  6. Calorimetric and Magnetic Study of the Holmium

    NASA Astrophysics Data System (ADS)

    Henry, Laurence L.

    Calorimetric measurements have been performed on a series of cubic Laves phase compounds Ho(Co _{rm 1-x}Rh_ {rm x})_2 for x = 0.02, 0.05, 0.08, 0.12, 0.16, and 0.25. The heat capacity data show first-order type peaks at the ferromagnetic transition temperature T_{rm c} for concentrations with x- values between 0.02 and 0.08. For larger concentrations, the peaks at T_{rm c} are much broader and more suggestive of a second-order transition. Utilizing the "s-d" model in conjunction with the specific heat data suggests that the change from first- to second-order in the ferromagnetic transition for x _sp{ ~}{>} 0.10 is due to a reduction in the magnetic exchange interactions between the Ho 4f moments and the cobalt 3d electrons. In addition, the calorimetric data for x <=q 0.16 show another first-order peak at a lower temperature T _{rm sf} which can be associated with a change in the easy magnetization direction of the Ho moments.

  7. New calorimetric all-particle energy spectrum

    NASA Technical Reports Server (NTRS)

    Linsley, J.

    1985-01-01

    Both the maximum size N sub m and the sea level muon size N sub mu have been used separately to find the all-particle energy spectrum in the air shower domain. However the conversion required, whether from N sub m to E or from N sub mu to E, has customarily been carried out by means of calculations based on an assumed cascase model. It is shown here that by combining present data on N sub m and N sub mu spectra with data on: (1); the energy spectrum of air shower muons and (2) the average width of the electron profile, one can obtain empirical values of the N sub m to E and N sub mu to E conversion factors, and an empirical calorimetric all-particle spectrum, in the energy range 2 x 10 to the 6th power E 2 x 10 to the 9th power GeV.

  8. Radiation beam calorimetric power measurement system

    DOEpatents

    Baker, John; Collins, Leland F.; Kuklo, Thomas C.; Micali, James V.

    1992-01-01

    A radiation beam calorimetric power measurement system for measuring the average power of a beam such as a laser beam, including a calorimeter configured to operate over a wide range of coolant flow rates and being cooled by continuously flowing coolant for absorbing light from a laser beam to convert the laser beam energy into heat. The system further includes a flow meter for measuring the coolant flow in the calorimeter and a pair of thermistors for measuring the temperature difference between the coolant inputs and outputs to the calorimeter. The system also includes a microprocessor for processing the measured coolant flow rate and the measured temperature difference to determine the average power of the laser beam.

  9. Calorimetric study of peroxycarboxylic ester synthesis.

    PubMed

    Fritzsche, L; Knorr, A

    2009-04-30

    Exothermic reactions involving organic peroxides carry a high potential hazard and must be considered with care. A safe handling requires, among others, the assessment of thermal process safety, for which safety characteristics like overall heat production and the resulting adiabatic temperature rise are essential. The article presents the results of the calorimetric investigation of the synthesis of four peroxycarboxylic esters, three tert-Butyl and one tert-Amyl peroxycarboxylic ester. In the two-step synthesis the second one clearly shows the higher exothermic potential. The overall heat production lies in the range of 126-135 kJ/mol and is nearly independent of the carboxylic acid residual in the tert-Butyl peroxycarboxylic ester. The calculated adiabatic temperature rise is 70-80K. Influence of temperature and feed rate on the heat generation is discussed for one species. A grading of the synthesis with respect to temperature levels according to the criticality classes by Stoessel leads to the most critical for an exothermic reaction. PMID:18722058

  10. The CALorimetric Electron Telescope, CALET, Mission

    NASA Astrophysics Data System (ADS)

    Torii, Shoji

    We are developing the CALorimetric Electron Telescope, CALET, mission for the Japanese Experiment Module Exposed Facility, JEM-EF, of the International Space Station. Major scientific objectives are to search for nearby cosmic ray sources and dark matter by carrying out a precise measurement of the electrons in GeV 20 TeV and the gamma-rays in 20 MeV TeV. CALET has a unique capability to observe electrons and gamma-rays over 1 TeV since the hadron rejection power is more than 105 and the energy resolution better than a few percent over 100 GeV. The detector consists of an Imaging Calorimeter (IMC) with scintillating fiber belts and tungsten plates, a Total Absorption Calorimeter (TASC) with BGO logs, a Silicon Pixel Array (SIA) and a Scintillator Anti-Coincidence System (SACS). CALET has also a capability to measure protons and nuclei in 10 GeV 1000 TeV, and will have a function to monitor solar activity and gamma-ray bursts with additional instruments. The phase A study has started on a schedule of launch in 2013 by H-II Transfer Vehicle (HTV) for 5 years observation.

  11. Etude des phenomenes dynamiques ultrarapides et des caracteristiques impulsionnelles d'emission terahertz du supraconducteur YBCO

    NASA Astrophysics Data System (ADS)

    Savard, Stephane

    Les premieres etudes d'antennes a base de supraconducteurs a haute temperature critique emettant une impulsion electromagnetique dont le contenu en frequence se situe dans le domaine terahertz remontent a 1996. Une antenne supraconductrice est formee d'un micro-pont d'une couche mince supraconductrice sur lequel un courant continu est applique. Un faisceau laser dans le visible est focalise sur le micro-pont et place le supraconducteur dans un etat hors-equilibre ou des paires sont brisees. Grace a la relaxation des quasiparticules en surplus et eventuellement de la reformation des paires supraconductrices, nous pouvons etudier la nature de la supraconductivite. L'analyse de la cinetique temporelle du champ electromagnetique emis par une telle antenne terahertz supraconductrice s'est averee utile pour decrire qualitativement les caracteristiques de celle-ci en fonction des parametres d'operation tels que le courant applique, la temperature et la puissance d'excitation. La comprehension de l'etat hors-equilibre est la cle pour comprendre le fonctionnement des antennes terahertz supraconductrices a haute temperature critique. Dans le but de comprendre ultimement cet etat hors-equilibre, nous avions besoin d'une methode et d'un modele pour extraire de facon plus systematique les proprietes intrinseques du materiau qui compose l'antenne terahertz a partir des caracteristiques d'emission de celle-ci. Nous avons developpe une procedure pour calibrer le spectrometre dans le domaine temporel en utilisant des antennes terahertz de GaAs bombarde aux protons H+ comme emetteur et detecteur. Une fois le montage calibre, nous y avons insere une antenne emettrice dipolaire de YBa 2Cu3O7-delta . Un modele avec des fonctions exponentielles de montee et de descente du signal est utilise pour lisser le spectre du champ electromagnetique de l'antenne de YBa 2Cu3O7-delta, ce qui nous permet d'extraire les proprietes intrinseques de ce dernier. Pour confirmer la validite du modele

  12. Thermodynamic properties by non-calorimetric methods. Final report

    SciTech Connect

    Steele, W.V.; Chirico, R.D.; Collier, W.B.; Strube, M.M.; Klots, T.D. |

    1992-12-31

    This research program provided a valuable complement to the experimental programs currently in progress at NIPER for the Advanced Research and Technology Development (AR and TD) and Advanced Exploration and Process Technology (AEPT) divisions of the Department of Energy. These experimental programs are focused on the calorimetric determination of thermodynamic properties of key polynuclear heteroatom-containing aromatic molecules. The project for the Office of Energy Research focused on the non-calorimetric determination of thermodynamic properties through the extension of existing correlation methodologies and through molecular spectroscopy with statistical mechanics. The paper discusses the following studies: Group-contribution approach for polycyclic aromatic hydrocarbons (naphthalene, phenanthrene, anthracene, pyrene, 3-methylphenanthrene, benzoquinolines, biphenyl/hydrogen system); Group-contribution approach for key monocyclic organic compounds; Molecular spectroscopy and statistical mechanics; and Thermophysical property correlations.

  13. Micro-calorimetric sensor for trace explosive particle detection

    NASA Astrophysics Data System (ADS)

    Olsen, Jesper K.; Greve, Anders; Privorotskaya, N.; Senesac, L.; Thundat, T.; King, W. P.; Boisen, A.

    2010-04-01

    A micro differential thermal analysis (DTA) system is used for detection of trace explosive particles. The DTA system consists of two silicon micro chips with integrated heaters and temperature sensors. One chip is used for reference and one for the measurement sample. The sensor is constructed as a small silicon nitride bridge incorporating heater elements and a temperature measurement resistor. In this manuscript the DTA system is described and tested by measuring calorimetric response of DNT (2,4-Dinitrotoluene). The design of the senor is described and the temperature uniformity investigated using finite element modelings and Raman temperature measurements. The functionality is tested using two different kinds of explosive deposition techniques and calorimetric responses are obtained. Under the framework of the Xsense project at the Technical University of Denmark (DTU) which combines four independent sensing techniques, these micro DNT sensors will be included in handheld explosives detectors with applications in homeland security and landmine clearance.

  14. A no-calorimetric method for measuring SAR in MRI

    NASA Astrophysics Data System (ADS)

    Romano, Rocco; Acernese, Fausto; Barone, Fabrizio

    2011-04-01

    During an MR procedure, the patient absorbs a portion of the transmitted RF energy, which may result in tissue heating and other adverse effects, such as alterations in visual, auditory and neural functions. The Specific Absorption Rate (SAR), in W/kg, is the RF power absorbed per unit mass of tissue and is one of the most important parameters related with thermal effects and acts as a guideline for MRI safety. Strict limits to the SAR levels are imposed by patient safety international regulations (CEI - EN 60601 - 2 - 33) and SAR measurements are required in order to verify its respect. The recommended methods for mean SAR measurement are quite problematic and often require a maintenance man intervention and long stop machine. For example, in the CEI recommended pulse energy method, the presence of a maintenance man is required in order to correctly connect the required instrumentation; furthermore, the procedure is complex and requires remarkable processing and calculus. Simpler are the calorimetric methods, also if in this case long acquisition times are required in order to have significant temperature variations and accurate heat capacity knowledge (CEI - EN 60601 - 2 - 33). The phase transition method is a new no-calorimetric method to measure SAR in MRI which has the advantages to be very simple and to overcome all the typical calorimetric method problems. It does not require in gantry temperature measurements, any specific heat or heat capacity knowledge, but only mass and time measurement. On the other hand, it is necessary to establish if all deposited power SAR can be considered acquired and measured. In this paper, that will be shown.

  15. Measurement of the calorimetric energy scale in MINOS

    SciTech Connect

    Hartnell, Jeffrey J.

    2005-06-01

    MINOS is a long-baseline neutrino oscillation experiment. A neutrino beam is created at the Fermi National Accelerator Laboratory in Illinois and fired down through the Earth. Measurements of the energy spectra and composition of the neutrino beam are made both at the source using the Near detector and 735 km away at the Soudan Underground Laboratory in Minnesota using the Far detector. By comparing the spectrum and flavour composition of the neutrino beam between the two detectors neutrino oscillations can be observed. Such a comparison depends on the accuracy of the relative calorimetric energy scale. This thesis details a precise measurement of the calorimetric energy scale of the MINOS Far detector and Calibration detector using stopping muons with a new ''track window'' technique. These measurements are used to perform the relative calibration between the two detectors. This calibration has been accomplished to 1.7% in data and to significantly better than 2% in the Monte Carlo simulation, thus achieving the MINOS relative calibration target of 2%. A number of cross-checks have been performed to ensure the robustness of the calorimetric energy scale measurements. At the Calibration detector the test-beam energy between run periods is found to be consistent with the detector response to better than 2% after the relative calibration is applied. The muon energy loss in the MINOS detectors determined from Bethe-Bloch predictions, data and Monte Carlo are compared and understood. To estimate the systematic error on the measurement of the neutrino oscillation parameters caused by a relative miscalibration a study is performed. A 2% relative miscalibration is shown to cause a 0.6% bias in the values of {Delta}m{sup 2} and sin{sup 2}(2{theta}).

  16. The Level-0 calorimetric trigger of the NA62 experiment

    NASA Astrophysics Data System (ADS)

    Ammendola, R.; Barbanera, M.; Bizzarri, M.; Bonaiuto, V.; Ceccucci, A.; Checcucci, B.; De Simone, N.; Fantechi, R.; Federici, L.; Fucci, A.; Lupi, M.; Paoluzzi, G.; Papi, A.; Piccini, M.; Ryjov, V.; Salamon, A.; Salina, G.; Sargeni, F.; Venditti, S.

    2016-02-01

    The NA62 experiment at the CERN SPS aims at measuring the branching ratio of the very rare kaon decay K+ → π+ ν bar nu (expected 10-10) with a 10% background. Since an high-intensity kaon beam is required to collect enough statistics, the Level-0 trigger plays a fundamental role in both the background rejection and in the particle identification. The calorimetric trigger collects data from various calorimeters and it is able to identify clusters of energy deposit and determine their position, fine-time and energy. This paper describes the complete hardware commisioning and the setup of the trigger for the 2015 physics data taking.

  17. ASIC for calorimetric measurements in the astrophysical experiment NUCLEON

    NASA Astrophysics Data System (ADS)

    Atkin, E.; Voronin, A.; Karmanov, D.; Kudryashov, I.; Kovalev, I.; Shumikhin, V.

    2016-02-01

    A satellite with the NUCLEON apparatus was launched in Dec. 2014. The space NUCLEON project of ROSCOSMOS is designed to investigate cosmic ray nuclei energy spectra from 100 GeV to 1000 TeV as well as cosmic ray electron spectra from 20 GeV to 3 TeV. The method of energy determination by means of a silicon instrument for measuring the particle charge of cosmic rays and the calorimetric system were developed. The main parameters, that determine the quality of calorimetric systems are linearity of transfer characteristic and the dynamic range of input signals, which should reach 30 000 MIPs (minimum ionizing particles). The ASIC, satisfying these requirements, consisting of 32 channels with a unique dynamic range from 1 to 40000 MIPs, signal to noise ratio not less than 2.5 at a shaper peaking time of 2 μs and a low power consumption of 1.5 mW/channel has been designed. The first results of the ASIC functionality in space are presented.

  18. Adiabatic calorimetric decomposition studies of 50 wt.% hydroxylamine/water.

    PubMed

    Cisneros, L O; Rogers, W J; Mannan, M S

    2001-03-19

    Calorimetric data can provide a basis for determining potential hazards in reactions, storage, and transportation of process chemicals. This work provides calorimetric data for the thermal decomposition behavior in air of 50wt.% hydroxylamine/water (HA), both with and without added stabilizers, which was measured in closed cells with an automatic pressure tracking adiabatic calorimeter (APTAC). Among the data provided are onset temperatures, reaction order, activation energies, pressures of noncondensable products, thermal stability at 100 degrees C, and the effect of HA storage time. Discussed also are the catalytic effects of carbon steel, stainless steel, stainless steel with silica coating, inconel, titanium, and titanium with silica coating on the reaction self-heat rates and onset temperatures. In borosilicate glass cells, HA was relatively stable at temperatures up to 133 degrees C, where the HA decomposition self-heat rate reached 0.05 degrees C/min. The added stabilizers appeared to reduce HA decomposition rates in glass cells and at ambient temperatures. The tested metals and metal surfaces coated with silica acted as catalysts to lower the onset temperatures and increase the self-heat rates. PMID:11165058

  19. Novel micro-calorimetric spectroscopy for mine detection

    SciTech Connect

    Datskos, P.G. |; Rajic, S.; Egert, C.M.; Datskou, I.

    1998-03-01

    The authors have developed a novel micro-calorimetric spectroscopy technique that can be used in mine detection applications. In this technique target molecules are allowed to adsorb on the surface of sub-femtojoule sensitive micromechanical thermal detectors. The adsorption of molecules on the thermal detector surface causes a differential surface stress resulting in an initial trigger. By exposing each element in an array of thermal detectors to different photon wavelengths, an extremely sensitive and unique photothermal signature response can be obtained. The authors present their results on target chemicals adsorbed on the detector surface at sub-monolayer coverage levels. They will present infrared photothermal spectra for trace concentrations of diisopropyl methylphosphonate (DIMP), and trinitrotoluene (TNT) over the wavelength region 2.5 to 14.5 microns. They found that in the wavelength region 2.5 to 14.5 microns the photothermal spectra of DIMP and TNT exhibit a number of peaks and are in excellent agreement with infrared absorption spectra found in the literature. Chemical detectors based on micro-calorimetric spectroscopy can be used to sensitively sense small number of molecules adsorbed on a thermal detector surface. The photothermal signature resulting from photon irradiation can be used for improved chemical characterization.

  20. Preparation, structural, and calorimetric characterization of bicomponent metallic photonic crystals

    NASA Astrophysics Data System (ADS)

    Kozlov, M. E.; Murthy, N. S.; Udod, I.; Khayrullin, I. I.; Baughman, R. H.; Zakhidov, A. A.

    2007-03-01

    We report preparation and characterization of novel bicomponent metal-based photonic crystals having submicron three-dimensional (3D) periodicity. Fabricated photonic crystals include SiO2 sphere lattices infiltrated interstitially with metals, carbon inverse lattices filled with metal or metal alloy spheres, Sb inverse lattices, and Sb inverse lattices filled with Bi spheres. Starting from a face centered SiO2 lattice template, these materials were obtained by sequences of either templating and template extraction or templating, template extraction, and retemplating. Surprising high fidelity was obtained for all templating and template extraction steps. Scanning electron microscopy (SEM), small angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) were used to characterize the structure and the effects of the structure on calorimetric properties. To the best of our knowledge, SAXS data on metallic photonic crystals were collected for first time.

  1. Calorimetric study of tellurium rich Se-Te-Sn glasses

    NASA Astrophysics Data System (ADS)

    Heera, Pawan; Kumar, Anup; Jharwal, Manish; Sharma, Raman

    2016-05-01

    We report the calorimetric study of amorphous Se30Te70-x Snx alloys for x= 0, 1.5, 2.5, 4.5 in terms of kinetic parameters. The DSC curves recorded at four different heating rates are analyzed to determine the transition temperatures, activation energy, thermal stability, glass forming ability. The crystallization process has been investigated using Kissinger, Matusita, Augis and Bennett, and Gao and Wang models. Various kinetic parameters have been calculated for a better understanding of the growth mechanism. The glass transition temperatures Tg, onset crystallization Tc, peak crystallization Tp, and melting temperature Tm are found to increase with the increase in Sn content. The system under investigation is found to be thermally stable for at lower at% of Sn. The values of parameters HR, Hw, and S indicate that Glass forming ability (GFA) decays with an increase in Sn content.

  2. Nanoclay modified polycarbonate blend nanocomposites: Calorimetric and mechanical properties

    NASA Astrophysics Data System (ADS)

    Zicans, Janis; Meri, Remo Merijs; Ivanova, Tatjana; Berzina, Rita; Kalnins, Martins; Maksimovs, Roberts

    2014-05-01

    The research is devoted to characterization of polycarbonate (PC)/acrylonitrile-butadiene styrene (ABS) blend nanocomposites in respects to it mechanical and calorimetric properties. It is shown that PC blend with 10wt% of ABS is more suitable for development of polymer-clay nanocomposites than PC blend with 40wt.% of ABS. It is revealed that the greatest modulus and strength increment is observed for PC/10wt.%ABS blend nanocomposites, containing aromatic organomodifier treated clay (Dellite 43B). It is also determined that optimal nanofiller content for the investigated PC/10%ABS blend is 1.5 wt.%. Increase of mechanical characteristics of PC/10wt.%ABS blend nanocomposites is accompanied with the rise of glass transition temperatures of both polymeric phases, particularly that of PC.

  3. Calorimetric determination of the enthalpy of formation for pyrophyllite

    NASA Astrophysics Data System (ADS)

    Ogorodova, L. P.; Kiseleva, I. A.; Mel'Chakova, L. V.; Vigasina, M. F.; Spiridonov, E. M.

    2011-09-01

    A calorimetric study of the natural pyrophyllite was performed by high-temperature melt calorimetry on a Tian-Calvet calorimeter. Based on experimentally determined in this work for pyrophyllite and gibbsite, as well as previously obtained for corundum and quartz, the total value of the enthalpy increment for the sample heated from room temperature to 973 K and the enthalpy of dissolution at 973 K by Hess's law, the enthalpy of formation of pyrophyllite of Al2[(OH)2/Si4O10] composed of elements was calculated at 298.15 K: Δf H {el/o}(298.15 K) = -5639.8 ± 5.7 kJ/mol.

  4. Remote calorimetric detection of urea via flow injection analysis.

    PubMed

    Gaddes, David E; Demirel, Melik C; Reeves, W Brian; Tadigadapa, Srinivas

    2015-12-01

    The design and development of a calorimetric biosensing system enabling relatively high throughput sample analysis are reported. The calorimetric biosensor system consists of a thin (∼20 μm) micromachined Y-cut quartz crystal resonator (QCR) as a temperature sensor placed in close proximity to a fluidic chamber packed with an immobilized enzyme. Layer by layer enzyme immobilization of urease is demonstrated and its activity as a function of the number of layers, pH, and time has been evaluated. This configuration enables a sensing system where a transducer element is physically separated from the analyte solution of interest and is thereby free from fouling effects typically associated with biochemical reactions occuring on the sensor surface. The performance of this biosensing system is demonstrated by detection of 1-200 mM urea in phosphate buffer via a flow injection analysis (FIA) technique. Miniaturized fluidic systems were used to provide continuous flow through a reaction column. Under this configuration the biosensor has an ultimate resolution of less than 1 mM urea and showed a linear response between 0-50 mM. This work demonstrates a sensing modality in which the sensor itself is not fouled or contaminated by the solution of interest and the enzyme immobilized Kapton® fluidic reaction column can be used as a disposable cartridge. Such a system enables reuse and reliability for long term sampling measurements. Based on this concept a biosensing system is envisioned which can perform rapid measurements to detect biomarkers such as glucose, creatinine, cholesterol, urea and lactate in urine and blood continuously over extended periods of time. PMID:26479269

  5. A calorimetric investigation of spessartine: Vibrational and magnetic heat capacity

    NASA Astrophysics Data System (ADS)

    Dachs, Edgar; Geiger, Charles A.; Withers, Anthony C.; Essene, Eric J.

    2009-06-01

    The heat capacity ( Cp) of two synthetic spessartine samples (Sps) was measured on 20-30 mg-size samples in the temperature range 2-864 K by relaxation calorimetry (RC) and differential scanning calorimetry (DSC). The polycrystalline spessartine samples were synthesized in two different laboratories at high pressures and temperatures from glass and oxide-mixture starting materials and characterized by X-ray powder diffraction and electron-microprobe analysis. The low-temperature heat capacity data show a prominent lambda transition with a peak at 6.2 K, which is interpreted to be the result of a paramagnetic-antiferromagnetic phase transition. The DSC data around ambient T agree excellently with the RC data and can be represented by the Cp polynomial for T > 250 K: CpSps=610-3060·T-0.5-1.45·107·T-2+1.82·109·T-3. Integration of the low temperature Cp data yields a calorimetric standard entropy for the two different samples of So = 334.6 ± 2.7 J/mol · K and 336.0 ± 2.7 J/mol · K. The preferred standard third-law entropy for spessartine is So = 335.3 ± 3.8 J/mol · K, which is the mean value from the two separate determinations. The lattice (vibrational) heat capacity of spessartine was calculated using the single-parameter phonon dispersion model of Komada and Westrum. The lattice entropy at 298.15 K is Svib298.15=297.7J/mol·K, which represents 89% of the calorimetric entropy. The magnetic heat capacity and entropy of spessartine, Smag, at 298.15 K were also calculated. The Smag of the two samples is 38.7 and 37.4 J/mol · K, which is 87% and 83% of the maximum possible magnetic entropy given by 3Rln6 = 44.7 J/mol · K. Published model-dependent lattice-dynamic calculations of Svib298.15 are analyzed and compared to the experimental data. Using the calorimetrically determined So and the Cp polynomial for spessartine, together with high P- T experimental phase-equilibrium data on Mn 2+-Mg partitioning between garnet and olivine, allows calculation of the

  6. Calorimetric and relaxation properties of xylitol-water mixtures

    NASA Astrophysics Data System (ADS)

    Elamin, Khalid; Sjöström, Johan; Jansson, Helén; Swenson, Jan

    2012-03-01

    We present the first broadband dielectric spectroscopy (BDS) and differential scanning calorimetry study of supercooled xylitol-water mixtures in the whole concentration range and in wide frequency (10-2-106 Hz) and temperature (120-365 K) ranges. The calorimetric glass transition, Tg, decreases from 247 K for pure xylitol to about 181 K at a water concentration of approximately 37 wt. %. At water concentrations in the range 29-35 wt. % a plentiful calorimetric behaviour is observed. In addition to the glass transition, almost simultaneous crystallization and melting events occurring around 230-240 K. At higher water concentrations ice is formed during cooling and the glass transition temperature increases to a steady value of about 200 K for all higher water concentrations. This Tg corresponds to an unfrozen xylitol-water solution containing 20 wt. % water. In addition to the true glass transition we also observed a glass transition-like feature at 220 K for all the ice containing samples. However, this feature is more likely due to ice dissolution [A. Inaba and O. Andersson, Thermochim. Acta, 461, 44 (2007)]. In the case of the BDS measurements the presence of water clearly has an effect on both the cooperative α-relaxation and the secondary β-relaxation. The α-relaxation shows a non-Arrhenius temperature dependence and becomes faster with increasing concentration of water. The fragility of the solutions, determined by the temperature dependence of the α-relaxation close to the dynamic glass transition, decreases with increasing water content up to about 26 wt. % water, where ice starts to form. This decrease in fragility with increasing water content is most likely caused by the increasing density of hydrogen bonds, forming a network-like structure in the deeply supercooled regime. The intensity of the secondary β-relaxation of xylitol decreases noticeably already at a water content of 2 wt. %, and at a water content above 5 wt. % it has been replaced by a

  7. Estimation of the diversity between DNA calorimetric profiles, differential melting curves and corresponding melting temperatures.

    PubMed

    Chang, Chun-Ling; Fridman, Alexander S; Grigoryan, Inessa E; Galyuk, Elena N; Murashko, Oleg N; Hu, Chin-Kun; Lando, Dmitri Y

    2016-11-01

    The Poland-Fixman-Freire formalism was adapted for modeling of calorimetric DNA melting profiles, and applied to plasmid pBR 322 and long random sequences. We studied the influence of the difference (HGC -HAT ) between the helix-coil transition enthalpies of AT and GC base pairs on the calorimetric melting profile and on normalized calorimetric melting profile. A strong alteration of DNA calorimetrical profile with HGC -HAT was demonstrated. In contrast, there is a relatively slight change in the normalized profiles and in corresponding ordinary (optical) normalized differential melting curves (DMCs). For fixed HGC -HAT , the average relative deviation (S) between DMC and normalized calorimetric profile, and the difference between their melting temperatures (Tcal -Tm ) are weakly dependent on peculiarities of the multipeak fine structure of DMCs. At the same time, both the deviation S and difference (Tcal -Tm ) enlarge with the temperature melting range of the helix-coil transition. It is shown that the local deviation between DMC and normalized calorimetric profile increases in regions of narrow peaks distant from the melting temperature. PMID:27422497

  8. Fructose-selective calorimetric biosensor in flow injection analysis.

    PubMed

    Bhand, Sunil G; Soundararajan, Srimathi; Surugiu-Wärnmark, Ioana; Milea, Jaqueline Simona; Dey, Estera Szwajcer; Yakovleva, Maria; Danielsson, Bengt

    2010-05-23

    A highly selective, interference free biosensor for the measurement of fructose in real syrup samples was developed. The assay is based on the phosphorylation of D(-)fructose to fructose-6-phosphate by hexokinase and subsequent conversion of fructose-6-phosphate to fructose-1,6-biphosphate by fructose-6-phosphate-kinase. The heat liberated in the second reaction is monitored using an enzyme thermistor. The major advantages of this biosensor are rapid and selective measurement of fructose without the need to eliminate glucose and inexpensive FIA-based, mediator-free calorimetric measurement suitable for regular fructose analysis. This method was optimised for parameters, such as pH, ionic strength, interference, operational stability and shelf life. Good and reproducible linearity (0.5-6.0 mM) with a detection limit of 0.12 mM was obtained. Fructose determination in commercial syrup samples and spiked samples confirmed the reliability of this set-up and technique. The biosensor gave reproducible results with good overall stability for continuous measurements over a period of three months besides a useful shelf life of six months. The method could be used for routine fructose monitoring in food samples. PMID:20457296

  9. Differential scanning calorimetric studies of nickel titanium rotary endodontic instruments.

    PubMed

    Brantley, W A; Svec, T A; Iijima, M; Powers, J M; Grentzer, T H

    2002-08-01

    Differential scanning calorimetric (DSC) analyses were performed between -130 degrees and 100 degrees C on specimens prepared from nickel-titanium (NiTi) rotary endodontic instruments: ProFile (n = 5), Lightspeed (n = 4), and Quantec (n = 3). The ProFile and Lightspeed instruments were in the as-received condition, whereas the Quantec instruments were randomly selected from a dental clinic and had unknown history. The DSC plots showed that the ProFile and Lightspeed instruments analyzed had the superelastic NiTi property, with an austenite-finish (Af) temperature of approximately 25 degrees C. Differences in DSC plots for the ProFile instruments and the starting wire blanks (n = 2) were attributed to the manufacturing process. The phase transformation behavior when the specimens were heated and cooled between -130 degrees and 100 degrees C, the temperature ranges for the phase transformations, and the resulting enthalpy changes were similar to those previously reported for nickel-titanium orthodontic wires having superelastic characteristics or shape memory behavior in the oral environment. The experiments demonstrated that DSC is a powerful tool for materials characterization of these rotary instruments, providing direct information not readily available from other analytical techniques about the NiTi phases present, which are fundamentally responsible for their clinical behavior. PMID:12184415

  10. Adiabatic Heat of Hydration Calorimetric Measurements for Reference Saltstone Waste

    SciTech Connect

    Bollinger, James

    2006-01-12

    The production of nuclear materials for weapons, medical, and space applications from the mid-1950's through the late-1980's at the Savannah River Site (SRS) generated approximately 35 million gallons of liquid high-level radioactive waste, which is currently being processed into vitrified glass for long-term storage. Upstream of the vitrification process, the waste is separated into three components: high activity insoluble sludge, high activity insoluble salt, and very low activity soluble salts. The soluble salt represents 90% of the 35 million gallons of overall waste and is processed at the SRS Saltstone Facility, where it mixed with cement, blast furnace slag, and flyash, creating a grout-like mixture. The resulting grout is pumped into aboveground storage vaults, where it hydrates into concrete monoliths, called saltstone, thus immobilizing the low-level radioactive salt waste. As the saltstone hydrates, it generates heat that slowly diffuses out of the poured material. To ensure acceptable grout properties for disposal and immobilization of the salt waste, the grout temperature must not exceed 95 C during hydration. Adiabatic calorimetric measurements of the heat generated for a representative sample of saltstone were made to determine the time-dependent heat source term. These measurements subsequently were utilized as input to a numerical conjugate heat transfer model to determine the expected peak temperatures for the saltstone vaults.

  11. Thermodynamic properties of chlorite and berthierine derived from calorimetric measurements

    NASA Astrophysics Data System (ADS)

    Blanc, Philippe; Gailhanou, Hélène; Rogez, Jacques; Mikaelian, Georges; Kawaji, Hitoshi; Warmont, Fabienne; Gaboreau, Stéphane; Grangeon, Sylvain; Grenèche, Jean-Marc; Vieillard, Philippe; Fialips, Claire I.; Giffaut, Eric; Gaucher, Eric C.; Claret, F.

    2014-09-01

    In the context of the deep waste disposal, we have investigated the respective stabilities of two iron-bearing clay minerals: berthierine ISGS from Illinois [USA; (Al0.975FeIII0.182FeII1.422Mg0.157Li0.035Mn0.002)(Si1.332Al0.668)O5(OH)4] and chlorite CCa-2 from Flagstaff Hill, California [USA; (Si2.633Al1.367)(Al1.116FeIII0.215Mg2.952FeII1.712Mn0.012Ca0.011)O10(OH)8]. For berthierine, the complete thermodynamic dataset was determined at 1 bar and from 2 to 310 K, using calorimetric methods. The standard enthalpies of formation were obtained by solution-reaction calorimetry at 298.15 K, and the heat capacities were measured by heat-pulse calorimetry. For chlorite, the standard enthalpy of formation is measured by solution-reaction calorimetry at 298.15 K. This is completing the entropy and heat capacity obtained previously by Gailhanou et al. (Geochim Cosmochim Acta 73:4738-4749, 2009) between 2 and 520 K, by using low-temperature adiabatic calorimetry and differential scanning calorimetry. For both minerals, the standard entropies and the Gibbs free energies of formation at 298.15 K were then calculated. An assessment of the measured properties could be carried out with respect to literature data. Eventually, the thermodynamic dataset allowed realizing theoretical calculations concerning the berthierine to chlorite transition. The latter showed that, from a thermodynamic viewpoint, the main factor controlling this transition is probably the composition of the berthierine and chlorite minerals and the nature of the secondary minerals rather than temperature.

  12. Calorimetric method for determination of {sup 51}Cr neutrino source activity

    SciTech Connect

    Veretenkin, E. P. Gavrin, V. N.; Danshin, S. N.; Ibragimova, T. V.; Kozlova, Yu. P.; Mirmov, I. N.

    2015-12-15

    Experimental study of nonstandard neutrino properties using high-intensity artificial neutrino sources requires the activity of the sources to be determined with high accuracy. In the BEST project, a calorimetric system for measurement of the activity of high-intensity (a few MCi) neutrino sources based on {sup 51}Cr with an accuracy of 0.5–1% is created. In the paper, the main factors affecting the accuracy of determining the neutrino source activity are discussed. The calorimetric system design and the calibration results using a thermal simulator of the source are presented.

  13. "Cirque du Freak."

    ERIC Educational Resources Information Center

    Rivett, Miriam

    2002-01-01

    Considers the marketing strategies that underpin the success of the "Cirque du Freak" series. Describes how "Cirque du Freak" is an account of events in the life of schoolboy Darren Shan. Notes that it is another reworking of the vampire narrative, a sub-genre of horror writing that has proved highly popular with both adult and child readers. (SG)

  14. Heat capacty, relative enthalpy, and calorimetric entropy of silicate minerals: an empirical method of prediction.

    USGS Publications Warehouse

    Robinson, G.R., Jr.; Haas, J.L., Jr.

    1983-01-01

    Through the evaluation of experimental calorimetric data and estimates of the molar isobaric heat capacities, relative enthalpies and entropies of constituent oxides, a procedure for predicting the thermodynamic properties of silicates is developed. Estimates of the accuracy and precision of the technique and examples of its application are also presented. -J.A.Z.

  15. The du Bois sign.

    PubMed

    Voelpel, James H; Muehlberger, Thomas

    2011-03-01

    According to the current literature, the term "du Bois sign" characterizes the condition of a shortened fifth finger as a symptom of congenital syphilis, Down syndrome, dyscrania, and encephalic malformation. Modern medical dictionaries and text books attribute the eponym to the French gynecologist Paul Dubois (1795-1871). Yet, a literature analysis revealed incorrect references to the person and unclear definitions of the term. Our findings showed that the origin of the term is based on observations made by the Swiss dermatologist Charles du Bois (1874-1947) in connection with congenital syphilis. In addition, a further eponymical fifth finger sign is closely associated with the du Bois sign. In conclusion, the du Bois sign has only limited diagnostic value and is frequently occurring in the normal healthy population. PMID:21263293

  16. The calorimetric spectrum of the electron-capture decay of 163Ho. The spectral endpoint region

    NASA Astrophysics Data System (ADS)

    De Rújula, A.; Lusignoli, M.

    2016-05-01

    The electron-neutrino mass (or masses and mixing angles) may be directly measurable in weak electron-capture decays. The favoured experimental technique is "calorimetric". The optimal nuclide is 163Ho, and several experiments (ECHo, HOLMES and NuMECS) are currently studying its decay. The most relevant range of the calorimetric-energy spectrum extends for the last few hundred eV below its endpoint. It has not yet been well measured. We explore the theory, mainly in the cited range, of electron capture in 163Ho decay. A so far neglected process turns out to be most relevant: electron-capture accompanied by the shake-off of a second electron. Our two main conclusions are very encouraging: the counting rate close to the endpoint may be more than an order of magnitude larger than previously expected; the "pile-up" problem may be significantly reduced.

  17. An Improved Formulation for Calorimetric Emittance Testing of Spacecraft Thermal Control Coatings

    NASA Technical Reports Server (NTRS)

    Kauder, Lonny R.

    2008-01-01

    Spacecraft often really heavily on passive thermal control to maintain operating temperature. An important parameter in the spacecraft heat balance equation is the emittance of thermal control coatings as a function of coating temperature. One method for determining the emittance of spacecraft thermal control from elevated temperature to cryogenic temperatures relies on a calorimetric technique. The fundamental equation governing this test method can be found in numerous places in the literature and although it generally provides reasonable results, its formulation is based on a conceptual flaw that only becomes apparent when the sample temperature approaches the wall temperature during testing. This paper investigates the cause for this error and develops the correct formulation for calorimetric emittance testing. Experimental data will also be presented that illustrates the difference between the two formulations and the resulting difference in the calculated emittance.

  18. GYROTRON POWER BALANCE BASED ON CALORIMETRIC MEASUREMENTS IN THE DIII-D ECH SYSTEM

    SciTech Connect

    GORELOV,I.A; LOHR,J.M; BAITY,JR.,F.W; CAHALAN,P; CALLIS,R.W; PONCE,D; CHIU,H.K

    2003-10-01

    OAK-B135 A powerful microwave system operating at the second harmonic of the electron cyclotron frequency on the DIII-D tokamak was upgraded up to six assemblies of 110 GHz gyrotrons in 2003. three Gycom gyrotrons nominally generate 750 kW for 2 s pulses, with the pulse length limit resulting from the peak temperature allowed on the boron nitride rf output window. Three Communications and Power Industries (CPI) gyrotrons with diamond windows have been recently installed and have been tested to 0.9-1.0 MW for 5 s pulses. Heat loading on internal parts of the gyrotrons, the matching optics unit and the dummy loads is measured calorimetrically. This paper discusses the calorimetry system and calorimetric measurements of gyrotron performance.

  19. Ultra-Responsive Thermal Sensors for the Detection of Explosives Using Calorimetric Spectroscopy (CalSpec)

    SciTech Connect

    Datskos, P.G.; Datskou, I.; Marlar, T.A.; Rajic, S.

    1999-04-05

    We have developed a novel chemical detection technique based on infrared micro-calorimetric spectroscopy that can be used to identify the presence of trace amounts of very low vapor pressure target compounds. Unlike numerous recently developed low-cost sensor approaches, the selectivity is derived from the unique differential temperature spectrum and does not require the questionable reliability of highly selective coatings to achieve the required specificity. This is accomplished by obtaining the infrared micro-calorimetric absorption spectrum of a small number of molecules absorbed on the surface of a thermal detector after illumination through a scanning monochromator. We have obtained infrared micro-calorimetric spectra for explosives such as TNT over the wavelength region 2.5 to 14.5 Mu-m. Thus both sophisticated and relatively crude explosive compounds and components are detectable with these ultra-sensitive thermal-mechanical micro-structures. In addition to the above mentioned spectroscopy technique and associated data, the development of these advanced thermal detectors is also presented in detail.

  20. Nanowell-patterned TiO{sub 2} microcantilevers for calorimetric chemical sensing

    SciTech Connect

    Lee, Dongkyu Chae, Inseok; Thundat, Thomas; Kim, Seonghwan; Jeon, Sangmin

    2014-04-07

    A sensitive calorimetric sensor using a TiO{sub 2} microcantilever with nanowells patterned on one of its sides is described. This single material cantilever is sensitive to temperature change without relying on the metal deposition-based bimetallic effect. The thermomechanical sensitivity originates from the structure dependent variations in both the elastic modulus and thermal expansion coefficient due to the presence of ordered nanowells. These cantilever beams offer an alternate and efficient chemical sensing route for vapor phase analytes using photothermal spectroscopy. Selective and sensitive detection of organophosphorus compounds, as well as their photocatalytic decomposition under ultraviolet light exposure are demonstrated.

  1. Calorimetric support of directional-hemispherical reflection measurements in the infrared spectral range.

    PubMed

    Richter, W; Sarge, S M; Kämmer, F

    1994-03-01

    Measurements of the directional-hemispherical reflectance ρ with the Physikalisch-Technische Bundesanstalt IR sphere reflectometer have been confirmed by calorimetric determination of the absorptance α in the same geometrical conditions (irradiation at 10°, hemispherical reflection). The good agreement of ρ with (1 - α) on both highly reflecting and low-reflecting surfaces indicates that in the mid-IR spectral range the integrating sphere reflectometer is capable of essentially correct reflectance measurements of diffusely reflecting surfaces, with an estimated uncertainty of 0.01 after correction for a small systematic deviation. This capability opens up the possibility of developing IR reflectance standards. PMID:20862150

  2. Relativistic electron precipitation at International Space Station: Space weather monitoring by Calorimetric Electron Telescope

    NASA Astrophysics Data System (ADS)

    Kataoka, Ryuho; Asaoka, Yoichi; Torii, Shoji; Terasawa, Toshio; Ozawa, Shunsuke; Tamura, Tadahisa; Shimizu, Yuki; Akaike, Yosui; Mori, Masaki

    2016-05-01

    The charge detector (CHD) of the Calorimetric Electron Telescope (CALET) on board the International Space Station (ISS) has a huge geometric factor for detecting MeV electrons and is sensitive to relativistic electron precipitation (REP) events. During the first 4 months, CALET CHD observed REP events mainly at the dusk to midnight sector near the plasmapause, where the trapped radiation belt electrons can be efficiently scattered by electromagnetic ion cyclotron (EMIC) waves. Here we show that interesting 5-20 s periodicity regularly exists during the REP events at ISS, which is useful to diagnose the wave-particle interactions associated with the nonlinear wave growth of EMIC-triggered emissions.

  3. Thermodynamic properties by non-calorimetric methods. Progress report, August 1, 1988--July 31, 1989

    SciTech Connect

    Steele, W.V.; Chirico, R.D.; Collier, W.B.; Strube, M.M. |

    1989-12-31

    This three year research program provides a valuable complement to the experimental programs currently in progress at NIPER for the Advanced Research and Technology Development (AR and TD) and Advanced Exploration and Process Technology (AEPT) divisions of the Department of Energy. These experimental programs are focused on the calorimetric determination of thermodynamic properties of key polynuclear heteroatom-containing aromatic molecules. This project for the Office of Energy Research focuses on the non-calorimetric determination of thermodynamic properties through the extension of existing correlation methodologies and through molecular spectroscopy with statistical mechanics. The paper discusses progress in three areas: (1) Improvement of thermochemical and thermophysical property predictions via enhancement of group-contribution methods using two approaches, namely, development and improvement of group-contribution parameters via correlations involving the expanded modern thermodynamics data base and development of group-contribution parameters via molecular spectroscopy and statistical mechanics of key monocyclic organic compounds; (2) Molecular spectroscopy and statistical mechanics: equipment development and developments in interpretation and assignment of spectra; and (3) Thermophysical property correlations.

  4. Thermodynamic Properties of Liquid Silver-Antimony-Tin Alloys Determined from Electrochemical and Calorimetric Measurements

    NASA Astrophysics Data System (ADS)

    Łapsa, Joanna; Onderka, Bogusław

    2016-08-01

    The thermodynamic properties of liquid Ag-Sb-Sn alloys were obtained through use of the drop solution calorimetric method and electromotive force (emf) measurements of galvanic cells with a yttria stabilized zirconia (YSZ) solid electrolyte. The experiments were carried out along Ag0.25Sb0.75, Ag0.5Sb0.5 and Ag0.75Sb0.25 sections of the ternary system in the temperature range from 973 K to 1223 K. From the measured emf, the tin activity in liquid solutions of Ag-Sb-Sn was determined for the first time. The partial and integral enthalpy of mixing were determined from calorimetric measurements at two temperatures. These measurements were performed along two cross-sections: Sb0.5Sn0.5 at 912 K and 1075 K, and Ag0.75Sb0.25 at 1075 K. Both experimental data sets were used to find ternary interaction parameters by applying the Redlich-Kister-Muggianu model of the substitutional solution. Consequently, the set of parameters describing the thermodynamic properties of the liquid phase was derived.

  5. Comparison of the calorimetric and kinematic methods of neutrino energy reconstruction in disappearance experiments

    SciTech Connect

    Ankowski, Artur M.; Benhar, Omar; Coloma, Pilar; Huber, Patrick; Jen, Chun -Min; Mariani, Camillo; Meloni, Davide; Vagnoni, Erica

    2015-10-22

    To be able to achieve their physics goals, future neutrino-oscillation experiments will need to reconstruct the neutrino energy with very high accuracy. In this work, we analyze how the energy reconstruction may be affected by realistic detection capabilities, such as energy resolutions, efficiencies, and thresholds. This allows us to estimate how well the detector performance needs to be determined a priori in order to avoid a sizable bias in the measurement of the relevant oscillation parameters. We compare the kinematic and calorimetric methods of energy reconstruction in the context of two νμ → νμ disappearance experiments operating in different energy regimes. For the calorimetric reconstruction method, we find that the detector performance has to be estimated with an O(10%) accuracy to avoid a significant bias in the extracted oscillation parameters. Thus, in the case of kinematic energy reconstruction, we observe that the results exhibit less sensitivity to an overestimation of the detector capabilities.

  6. Thermodynamic Properties of Liquid Silver-Antimony-Tin Alloys Determined from Electrochemical and Calorimetric Measurements

    NASA Astrophysics Data System (ADS)

    Łapsa, Joanna; Onderka, Bogusław

    2016-05-01

    The thermodynamic properties of liquid Ag-Sb-Sn alloys were obtained through use of the drop solution calorimetric method and electromotive force (emf) measurements of galvanic cells with a yttria stabilized zirconia (YSZ) solid electrolyte. The experiments were carried out along Ag0.25Sb0.75, Ag0.5Sb0.5 and Ag0.75Sb0.25 sections of the ternary system in the temperature range from 973 K to 1223 K. From the measured emf, the tin activity in liquid solutions of Ag-Sb-Sn was determined for the first time. The partial and integral enthalpy of mixing were determined from calorimetric measurements at two temperatures. These measurements were performed along two cross-sections: Sb0.5Sn0.5 at 912 K and 1075 K, and Ag0.75Sb0.25 at 1075 K. Both experimental data sets were used to find ternary interaction parameters by applying the Redlich-Kister-Muggianu model of the substitutional solution. Consequently, the set of parameters describing the thermodynamic properties of the liquid phase was derived.

  7. Kinetics of degradation of diclofenac sodium in aqueous solution determined by a calorimetric method.

    PubMed

    Chadha, R; Kashid, N; Jain, D V S

    2003-09-01

    An isothermal heat conduction microcalorimeter has been used to study the stability of diclofenac sodium both alone and its inclusion complex with beta-cyclodextrin in aqueous solution. The rates of heat evolved during degradation of diclofenac sodium have been measured by a highly sensitive microcalorimetric technique as function of concentration, pH and temperature. The calorimetric accessible data have been incorporated in the equations for determination of rate constants, change in enthalpy and order of reaction. The decomposition of diclofenac sodium both alone and its inclusion complex with beta-cyclodextrin in solution corresponds to a pseudo-first order reaction. The values of rate constants, k's at 338.15 K, (calculated from the variation of heat evolution with the time) for the degradation of diclofenac sodium at pH 5, 6, 7, 8 and its inclusion complex with beta-cyclodextrin at pH 7 are found to be 4.71 x 10(-4), 5.69 x 10(-4), 6.12 x 10(-)4, 6.57 x 10(-4) and 4.26 x 10(-4) h(-1) respectively. There is good agreement between calorimetric determined t(0.5) and literature values. It has been found that beta-cyclodextrin retards the degradation of diclofenac sodium. The kinetic parameters have been calculated for the reaction. The negative entropy of activation suggests the formation of an ordered transition state. PMID:14531458

  8. Calorimetric method of ac loss measurement in a rotating magnetic field.

    PubMed

    Ghoshal, P K; Coombs, T A; Campbell, A M

    2010-07-01

    A method is described for calorimetric ac-loss measurements of high-T(c) superconductors (HTS) at 80 K. It is based on a technique used at 4.2 K for conventional superconducting wires that allows an easy loss measurement in parallel or perpendicular external field orientation. This paper focuses on ac loss measurement setup and calibration in a rotating magnetic field. This experimental setup is to demonstrate measuring loss using a temperature rise method under the influence of a rotating magnetic field. The slight temperature increase of the sample in an ac-field is used as a measure of losses. The aim is to simulate the loss in rotating machines using HTS. This is a unique technique to measure total ac loss in HTS at power frequencies. The sample is mounted on to a cold finger extended from a liquid nitrogen heat exchanger (HEX). The thermal insulation between the HEX and sample is provided by a material of low thermal conductivity, and low eddy current heating sample holder in vacuum vessel. A temperature sensor and noninductive heater have been incorporated in the sample holder allowing a rapid sample change. The main part of the data is obtained in the calorimetric measurement is used for calibration. The focus is on the accuracy and calibrations required to predict the actual ac losses in HTS. This setup has the advantage of being able to measure the total ac loss under the influence of a continuous moving field as experienced by any rotating machines. PMID:20687748

  9. Calorimetric method of ac loss measurement in a rotating magnetic field

    NASA Astrophysics Data System (ADS)

    Ghoshal, P. K.; Coombs, T. A.; Campbell, A. M.

    2010-07-01

    A method is described for calorimetric ac-loss measurements of high-Tc superconductors (HTS) at 80 K. It is based on a technique used at 4.2 K for conventional superconducting wires that allows an easy loss measurement in parallel or perpendicular external field orientation. This paper focuses on ac loss measurement setup and calibration in a rotating magnetic field. This experimental setup is to demonstrate measuring loss using a temperature rise method under the influence of a rotating magnetic field. The slight temperature increase of the sample in an ac-field is used as a measure of losses. The aim is to simulate the loss in rotating machines using HTS. This is a unique technique to measure total ac loss in HTS at power frequencies. The sample is mounted on to a cold finger extended from a liquid nitrogen heat exchanger (HEX). The thermal insulation between the HEX and sample is provided by a material of low thermal conductivity, and low eddy current heating sample holder in vacuum vessel. A temperature sensor and noninductive heater have been incorporated in the sample holder allowing a rapid sample change. The main part of the data is obtained in the calorimetric measurement is used for calibration. The focus is on the accuracy and calibrations required to predict the actual ac losses in HTS. This setup has the advantage of being able to measure the total ac loss under the influence of a continuous moving field as experienced by any rotating machines.

  10. Comparison of the calorimetric and kinematic methods of neutrino energy reconstruction in disappearance experiments

    DOE PAGESBeta

    Ankowski, Artur M.; Benhar, Omar; Coloma, Pilar; Huber, Patrick; Jen, Chun -Min; Mariani, Camillo; Meloni, Davide; Vagnoni, Erica

    2015-10-22

    To be able to achieve their physics goals, future neutrino-oscillation experiments will need to reconstruct the neutrino energy with very high accuracy. In this work, we analyze how the energy reconstruction may be affected by realistic detection capabilities, such as energy resolutions, efficiencies, and thresholds. This allows us to estimate how well the detector performance needs to be determined a priori in order to avoid a sizable bias in the measurement of the relevant oscillation parameters. We compare the kinematic and calorimetric methods of energy reconstruction in the context of two νμ → νμ disappearance experiments operating in different energymore » regimes. For the calorimetric reconstruction method, we find that the detector performance has to be estimated with an O(10%) accuracy to avoid a significant bias in the extracted oscillation parameters. Thus, in the case of kinematic energy reconstruction, we observe that the results exhibit less sensitivity to an overestimation of the detector capabilities.« less

  11. Stabilization of Cu(I) for binding and calorimetric measurements in aqueous solution†

    PubMed Central

    Johnson, Destinee K.; Stevenson, Michael J.; Almadidy, Zayed A.; Jenkins, Sharon E.; Wilcox, Dean. E.; Grossoehme, Nicholas E.

    2015-01-01

    Conditions have been developed for the comproportionation reaction of Cu2+ and copper metal to prepare aqueous solutions of Cu+ that are stabilized from disproportionation by MeCN and other Cu+-stabilizing ligands. These solutions were then used in ITC measurements to quantify the thermodynamics of formation of a set of Cu+ complexes (CuI(MeCN)3+, CuIMe6Trien+, CuI(BCA)23−, CuI(BCS)23−), which have stabilities ranging over 15 orders of magnitude, for their use in binding and calorimetric measurements of Cu+ interaction with proteins and other biological macromolecules. These complexes were then used to determine the stability and thermodynamics of formation of a 1 : 1 complex of Cu+ with the biologically important tri-peptide glutathione, GSH. These results identify Me6Trien as an attractive Cu+-stabilizing ligand for calorimetric experiments, and suggest that caution should be used with MeCN to stabilize Cu+ due to its potential for participating in unquantifiable ternary interactions. PMID:26327397

  12. Calorimetric Thermoelectric Gas Sensor for the Detection of Hydrogen, Methane and Mixed Gases

    PubMed Central

    Park, Nam-Hee; Akamatsu, Takafumi; Itoh, Toshio; Izu, Noriya; Shin, Woosuck

    2014-01-01

    A novel miniaturized calorimeter-type sensor device with a dual-catalyst structure was fabricated by integrating different catalysts on the hot (Pd/θ-Al2O3) and cold (Pt/α-Al2O3) ends of the device. The device comprises a calorimeter with a thermoelectric gas sensor (calorimetric-TGS), combining catalytic combustion and thermoelectric technologies. Its response for a model fuel gas of hydrogen and methane was investigated with various combustor catalyst compositions. The calorimetric-TGS devices detected H2, CH4, and a mixture of the two with concentrations ranging between 200 and 2000 ppm at temperatures of 100–400 °C, in terms of the calorie content of the gases. It was necessary to reduce the much higher response voltage of the TGS to H2 compared to CH4. We enhanced the H2 combustion on the cold side so that the temperature differences and response voltages to H2 were reduced. The device response to H2 combustion was reduced by 50% by controlling the Pt concentration in the Pt/α-Al2O3 catalyst on the cold side to 3 wt%. PMID:24818660

  13. Calorimetric method of ac loss measurement in a rotating magnetic field

    SciTech Connect

    Ghoshal, P. K.; Coombs, T. A.; Campbell, A. M.

    2010-07-15

    A method is described for calorimetric ac-loss measurements of high-T{sub c} superconductors (HTS) at 80 K. It is based on a technique used at 4.2 K for conventional superconducting wires that allows an easy loss measurement in parallel or perpendicular external field orientation. This paper focuses on ac loss measurement setup and calibration in a rotating magnetic field. This experimental setup is to demonstrate measuring loss using a temperature rise method under the influence of a rotating magnetic field. The slight temperature increase of the sample in an ac-field is used as a measure of losses. The aim is to simulate the loss in rotating machines using HTS. This is a unique technique to measure total ac loss in HTS at power frequencies. The sample is mounted on to a cold finger extended from a liquid nitrogen heat exchanger (HEX). The thermal insulation between the HEX and sample is provided by a material of low thermal conductivity, and low eddy current heating sample holder in vacuum vessel. A temperature sensor and noninductive heater have been incorporated in the sample holder allowing a rapid sample change. The main part of the data is obtained in the calorimetric measurement is used for calibration. The focus is on the accuracy and calibrations required to predict the actual ac losses in HTS. This setup has the advantage of being able to measure the total ac loss under the influence of a continuous moving field as experienced by any rotating machines.

  14. ESTIMATION OF BARE-SOIL EVAPORATION USING A CALORIMETRIC APPROACH WITH HEAT FLUX MEASURED AT MULTIPLE DEPTHS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An assumption in calorimetric methods for soil heat flux is that sensible heat terms can be balanced (i.e., if the heat flux is known at one depth, the heat flux at another depth may be determined by monitoring the change in heat storage). Latent heat from water evaporation is assigned to the energy...

  15. Calorimetric determination of thermal parameters for the Li/BrCl in SOCl2 (BCX) chemistry

    NASA Technical Reports Server (NTRS)

    Darcy, Eric C.; Kalu, Eric E.; White, Ralph E.

    1990-01-01

    The heat capacity of a Li-BCX DD-cell was found to be dependent on its state of charge by drop calorimetry measurements. The method of drop calorimetry involves measuring the energy (joules) gained or lost from a sample that is transferred from a bath at temperature A to one at temperature B. The thermoneutral potential is defined as the cell potential where the cell electrochemical reactions are neither exothermic nor endothermic. A Hart scientific calorimeter system, Model No. S77XX, designed for heat conduction calorimetry and drop calorimetry was used. Calorimetric analysis yielded a thermoneutral potential of 4.14 volts and a cell heat capacity dependent on the state of charge.

  16. Molecular mobility and relaxation process of isolated lignin studied by multifrequency calorimetric experiments.

    PubMed

    Guigo, Nathanael; Mija, Alice; Vincent, Luc; Sbirrazzuoli, Nicolas

    2009-02-28

    The glass transition of lignin has been studied by multifrequency calorimetric measurements in order to highlight the morphological changes and the dynamic aspects associated to this relaxation process. Influences of water sorption and thermal annealing on molecular mobility have been considered. Additional investigations by thermogravimetry, infra-red spectroscopy and rheometry have been performed to corroborate the claims. The relaxation process of annealed lignin shows a different behaviour as the consequence of micro-structural modifications of lignin. These are explained by redistribution of secondary bonds as well as formation of new interunit linkages. Concerning the dynamic aspects, apparent activation energy, E, and sizes of cooperatively rearranging region, V(crr), have been evaluated respectively from the frequency dependence and heat capacity measurements of the glass transition. Compared to dried lignin, both E and V(crr) significantly decrease in a water-sorbed matrix indicating that the three-dimensional structure presents a higher mobility and is less confined. PMID:19209367

  17. Biodegradable composites filled with halloysite nanonotubes: Calorimetric investigations and structural issues

    NASA Astrophysics Data System (ADS)

    Russo, Pietro; Vetrano, Barbara; Acierno, Domenico

    2012-07-01

    Halloysite nanotubes were dispersed in a commercially biodegradable blends by melt compounding. Bionanocomposites based on a film-grade commercial blend of poly(hydroxybutirate)-co-valerate PHBV and poly(butylene adipate-co-therephthalate) PBAT and containg up to 10% by weigth of tubular clays (HNTs) were prepared by using a twin-screw lab extruder and filmed by a film-blowing equipment. Film samples were subjected to thermal and structural investigations. Calorimetric analysis showed that signals shape is clearly affected by the heating and cooling rate, respectively. Structural investigations performed by X-Ray diffraction tests satisfactorily allowed to interpret thermal behavior highlighting the occurrence of different crystalline modifications, depending on the scanning thermal rate, the inclusion of filler and its chemical functionalization.

  18. A calorimetric study on interactions of colchicine with human serum albumin

    NASA Astrophysics Data System (ADS)

    Zhao, Qiang; Xu, Xiang-Yu; Sun, Xiang-Jun; Liu, Min; Sun, De-Zhi; Li, Lin-Wei

    2009-08-01

    Interaction of colchicine (COL) with human serum albumin (HSA) in buffer solutions (pH 7.2) has been investigated by isothermal titration calorimetry (ITC) combined with circular dichroism (CD) and UV-vis spectra. Heats of the interactions have been determined at 298.15 K. Based on the calorimetric data and reasonable suppositions for the bio-macromolecule - ligand binding process, the equilibrium constants, standard changes of enthalpy, entropy and Gibbs free energy of the processes are obtained. The results show that there are two classes of ligand binding sites. The first-class binding is mainly driven by entropy, while the second-class binding is synergistically driven by entropy and enthalpy. Circular dichroism (CD) and UV-vis spectra show that COL can change the secondary structure of HSA molecule.

  19. Emittance characterization of thermal control paints, coatings and surfaces using a calorimetric technique

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.

    1994-01-01

    Thermal control surfaces are used in every spacecraft thermal management system to dissipate heat through radiant heat transfer. This paper describes the thermal performance of several thermal control paints, coatings, and surfaces, as characterized by a calorimetric vacuum emissometer. The emissometer is designed to measure the functional emittance of a surface based on heat transfer from an underlying substrate to the surface and from the surface or near surface to a surrounding cold wall. Emittance measurements were made between 200 and 350 K. Polished aluminum, used here as a standard, was found to have a total hemispherical emittance of 0.06, as expected. A velvet black paint, also used here as a standard, was found to have an emittance of 0.94 at room temperature. Other surfaces of interest included a polyurethane-based black paint designated Z-306, a highly polished 316L stainless steel, and an atomic oxygen beam-textured carbon-carbon composite.

  20. Total hemispherical emittance measured at high temperatures by the calorimetric method

    SciTech Connect

    DiFilippo, F.; Mirtich, M.J.; Banks, B.A.; Stidham, C.; Kussmaul, M.

    1994-09-01

    A calorimetric vacuum emissometer (CVE) capable of measuring total hemispherical emittance of surfaces at elevated temperatures was designed, built, and tested. Several materials with a wide range of emittances were measured in the CVE between 773 to 923 K. These results were compared to values calculated from spectral emittance curves measured in a room temperature Hohlraum reflectometer and in an open-air elevated temperature emissometer. The results differed by as much as 0.2 for some materials but were in closer agreement for the more highly-emitting, diffuse-reflecting samples. The differences were attributed to temperature, atmospheric, and directional effects, and errors in the Hohlraum and emissometer measurements ({+-} 5 percent). The probable error of the CVE measurements was typically less than 1 percent.

  1. Total hemispherical emittance measured at high temperatures by the calorimetric method

    NASA Technical Reports Server (NTRS)

    Difilippo, Frank; Mirtich, Michael J.; Banks, Bruce A.; Stidham, Curtis; Kussmaul, Michael

    1989-01-01

    A calorimetric vacuum emissometer (CVE) capable of measuring total hemispherical emittance of surfaces at elevated temperatures was designed, built, and tested. Several materials with a wide range of emittances were measured in the CVE between 773 to 923 K. These results were compared to values calculated from spectral emittance curves measured in a room temperature Hohlraum reflectometer and in an open-air elevated temperature emissometer. The results differed by as much as 0.2 for some materials but were in closer agreement for the more highly-emitting, diffuse-reflecting samples. The differences were attributed to temperature, atmospheric, and directional effects, and errors in the Hohlraum and emissometer measurements (plus or minus 5 percent). The probable error of the CVE measurements was typically less than 1 percent.

  2. Direct calorimetric verification of thermodynamic instability of lead halide hybrid perovskites.

    PubMed

    Nagabhushana, G P; Shivaramaiah, Radha; Navrotsky, Alexandra

    2016-07-12

    Hybrid perovskites, especially methylammonium lead iodide (MAPbI3), exhibit excellent solar power conversion efficiencies. However, their application is plagued by poor chemical and structural stability. Using direct calorimetric measurement of heats of formation, MAPbI3 is shown to be thermodynamically unstable with respect to decomposition to lead iodide and methylammonium iodide, even in the absence of ambient air or light or heat-induced defects, thus limiting its long-term use in devices. The formation enthalpy from binary halide components becomes less favorable in the order MAPbCl3, MAPbBr3, MAPbI3, with only the chloride having a negative heat of formation. Optimizing the geometric match of constituents as measured by the Goldschmidt tolerance factor provides a potentially quantifiable thermodynamic guide for seeking chemical substitutions to enhance stability. PMID:27357677

  3. Calorimetric study on the effect of 60Co γ-rays on the growth of microorganisms

    NASA Astrophysics Data System (ADS)

    Wirkner, Sandra; Takahashi, Katsutada; Furuta, Masakazu; Hayashi, Toshio

    2002-03-01

    Using a calorimeter equipped with 24 sample units, the heat evolution from growing Saccharomyces cerevisiae, Escherichia coli and spores of Bacillus pumilus and Bacillus stearothermophilus was detected in the form of growth thermograms. Irradiation with 60Co γ-rays affected the growth pattern, which was used for a quantitative analysis of the effect on microorganisms. Irradiation of B. pumilus and B. stearothermophilus spores led to dose-dependent delays in growth, indicating a bactericidal effect. In case of 60Co γ-irradiated S. cerevisiae, a dose-dependent reduction of the growth rate constant was observed together with the retardation in growth, indicating a combination of bactericidal and bacteriostatic effects. An equation to determine the number of survivors on the basis of the retardation in growth tα and the growth rate constant μ was developed, which proved the opportunity to use the calorimetric technique in predictive microbiology.

  4. AC loss measurement of superconducting dipole magnets by the calorimetric method

    SciTech Connect

    Morita, Y.; Hara, K.; Higashi, N.; Kabe, A.

    1996-12-31

    AC losses of superconducting dipole magnets were measured by the calorimetric method. The magnets were model dipole magnets designed for the SSC. These were fabricated at KEK with 50-mm aperture and 1.3-m overall length. The magnet was set in a helium cryostat and cooled down to 1.8 K with 130 L of pressurized superfluid helium. Heat dissipated by the magnet during ramp cycles was measured by temperature rise of the superfluid helium. Heat leakage into the helium cryostat was 1.6 W and was subtracted from the measured heat to obtain AC loss of the magnet. An electrical measurement was carried out for calibration. Results of the two methods agreed within the experimental accuracy. The authors present the helium cryostat and measurement system in detail, and discuss the results of AC loss measurement.

  5. Calorimetric approach for 3D dosimetry of high intensity therapeutic electron beams

    NASA Astrophysics Data System (ADS)

    Lamanna, E.; Fiorillo, A. S.; Vena, R.; Berdondini, A.; Bettuzzi, M.; Brancaccio, R.; Casali, F.; Morigi, M. P.; Bilokon, H.; Barca, G.; Castrovillari, F.; Siaka, Y. F. T.

    2009-12-01

    The technique of High Dose Rate Intra-Operative Radiation Therapy (HDR-IORT) consists in the delivery of irradiation immediately after the removal of a cancerous mass, where the same incision is used to focalize the radiation to the tumour bed. Given its particular characteristics, IORT requires dose measurements that are different from those requested in external radiotherapy treatments. The main reason lies in the fact that in this case a single high dose must be delivered to a target volume whose extension and depth will be determined directly during the operation. Because of this peculiar characteristics, until now there is not a dosimetric system able to detect the electron beam giving at once a realtime response and an extensive spatial measure of the absorbed dose. Within the framework of a research project of the INFN (Italian National Institute of Nuclear Physics), we proposed a new system to overcome the problems, Dosiort. The final set-up is a solid phantom having a density approximately 1 g/cm3 with sensitive layers of scintillating fibres at fixed positions in a calorimetric configuration for the containment of electrons of energy 4-12 MeV. The prototype will be able to define the physical and geometrical characteristics of the electron beam (energy, isotropy, homogeneity, etc) and to measure the parameters needed to select the energy, the intensity and the Monitor Units (MU) for the exposition: percentage Depth Dose; beam profiles; isodose curves; values of dose per MU. In this work we present the results obtained by using two orthogonal layers of the calorimetric phantom Dosiort, in particular we report the measurement of the dynamic range of the read-out system and the first qualitative study of the results which can be extracted from the measurements taken in a test beam.

  6. Kyste hydatique primitif du sein

    PubMed Central

    Mouslik, Rabii; Settaf, Abdellatif; Elalami, Yacir; Lahnini, Hicham; Lahlou, Khalid; Chad, Bouziane

    2012-01-01

    Le kyste hydatique du sein est une parasitose rare même dans les pays endémiques. Nous rapportons une nouvelle observation d'une patiente de 30 ans qui présentait une masse du sein gauche. Le diagnostic de kyste hydatique du sein a été évoqué devant les données de l'examen clinique et de la mammographie couplée à l’échographie. Le geste chirurgical a consisté en une kystectomie. L'examen anatomopathologique de la pièce opératoire a confirmé le diagnostic. PMID:23133704

  7. Calorimetric output power measurements on a CW 20 kW 7.16 GHz microwave transmitter

    NASA Technical Reports Server (NTRS)

    Perez, Raul M.; Conroy, Bruce L.

    1991-01-01

    A calorimetric measurement technique developed for NASA's Deep Space Network (DSN) transmitters that does not require data on the coolant's thermal parameters is described. Calibration of the measurement system is achieved by measuring the DC input power to the klystron and relating coolant temperature increases to this known power dissipation. Agreement between calorimetric and electrical measurements of total system power was good, the difference being less than 2 percent. The operation of the system was not greatly affected by the composition of the coolant, which was varied from pure water to 40 percent ethylene glycol by mass. Good accuracy was also shown at output power levels, which varied over a 3.6:1 range.

  8. Differential scanning calorimetric evaluation of human meibomian gland secretions and model lipid mixtures: transition temperatures and cooperativity of melting

    PubMed Central

    Lu, Hua; Wojtowicz, Jadwiga C.; Butovich, Igor A.

    2013-01-01

    Meibomian gland secretions (or meibum) are produced by holocrine meibomian glands and are secreted in melted form onto the ocular surface of humans and animals to form a protective tear film lipid layer (TFLL). Its protective effect strongly depends on the composition and, hence, thermotropic behavior of meibum. The goal of our study was to quantitatively evaluate the melting characteristics of human meibum and model lipid mixtures using differential scanning microcalorimetry. Standard calorimetric parameters, e.g. changes in calorimetric enthalpy, transition temperatures T(m), cooperativity of melting etc. were assessed. We found that thermotropic behavior of meibum resembled that of relatively simple mixtures of unsaturated wax esters, but showed a lower change in calorimetric enthalpy, which can be indicative of a looser packing of lipids in meibum compared with pure standards and their simple mixtures. The cooperativity of melting of meibomian lipids was comparable to that of an equimolar mixture of four oleic-acid based wax esters. We demonstrated that the phase transitions in meibum start at about 10 to 15 °C and end at 35-36 °C, with T(m) being about 30 °C. The highly asymmetrical shape of the thermotropic peak of meibum is important for the physiology and biophysics of TFLL. PMID:23578711

  9. Calorimetric and theoretical study of the interaction between some saccharides and sodium halide in water.

    PubMed

    Zhuo, Kelei; Fu, Yingyi; Bai, Guangyue; Wang, Jianji; Yan, Haike; Wang, Hanqing

    2012-08-23

    Dilution enthalpies and mixing enthalpies of sodium halide and some saccharides (glucose, galactose, xylose, arabinose, fructose, and sucrose) in aqueous solution were determined by calorimetric measurements at 298.15 K. The values were used to determine enthalpic pair interaction parameters. Combined with Gibbs energy pair parameters, entropic pair interaction parameters were also obtained. Theoretical calculations at the B3LYP/6-311++G(d,p) level were carried out to provide the information of structures and thermodynamic functions. The information reveals the thermodynamic essence of the interactions between sodium halide and saccharides in aqueous solutions. The experimental results and theoretical calculations show that the sign of enthalpic pair interaction parameter 2υh(ES) is determined by the direct interaction between saccharides and ions, whereas the difference in value of 2υh(ES) for different saccharides or electrolytes depends on the partial dehydration of saccharides or anions in aqueous solution. The difference in value of entropic pair interaction parameters depends partly on the different dominant interactions in the process of partial dehydration of saccharides or ions. An enthalpy-entropy compensation relationship was observed for the sodium bromide-aldopyranose-water systems. Remarkably, it can be conjectured that the hydration entropy of glucose is lower than for other monosaccharides. Perhaps it is one of the reasons why glucose plays an important role in living organisms rather than other monosaccharides. PMID:22779908

  10. Calorimetric method for adjusting the mass of culture fluid in a bioreactor

    NASA Astrophysics Data System (ADS)

    Kotelnikov, G. V.; Moiseyeva, S. P.; Krayev, V. P.

    1998-05-01

    A new calorimetric method for adjusting the mass of culture fluid in a bioreactor and the results of its experimental testing are described. The method is based on constant heat capacity of liquids in the presence of disturbing factors accompanying biotechnology processes. A new measuring parameter independent of thermal noise induced by the stirrer, the flow of fluids, chemical and physical interactions of substances in the bioreactor was used for adjusting the mass of culture fluid. This parameter is Ph, the power increment in the heater under steady-state conditions of heating the bioreactor. The scanning calorimetry principle was used to make the measurements. It was shown that it is necessary to provide a constant heating rate V for the bioreactor and a high-speed response of the automated control system (ACS) for bioreactor temperature. The ACS developed on the base of the dynamic error and transient response h(t) calculated by the inverse Laplace transform with the use of the closed-loop transfer function gives V=const and the control time of about several seconds. The experimental data reported show the adjustment of the mass of culture fluid in a 3 l bioreactor with an error of no more than 10 g. This enables an accurate evaluation of the biomass amount in the bioreactor, specific growth rate, and other growth parameters determined using specific growth rate.

  11. First calorimetric determination of heat of extraction of 248Cm in a bi-phasic system

    SciTech Connect

    Leigh R. Martin; Peter R. Zalupski

    2011-06-01

    This report presents a summary of the work performed to meet FCR&D level 2 milestone M21SW050201, 'Complete the first calorimetric determination of heat of extraction of 248Cm in a bi-phasic system'. This work was carried out under the auspices of the Thermodynamics and Kinetics FCR&D work package. To complement previous work undertaken under this work package we have extended out heat of extraction studies by di-2-ethyl-hexyl-phosphoric acid to curium. This report also details the heat of extraction of samarium in the same system. This work was performed to not only test the methodology but also to check for consistency with the heats of extraction obtained with those in the prior literature. The heat of extraction for samarium that was obtained in this study was -9.6 kJ mol-1, which is in reasonable agreement with the previously obtained value of -10.9 kJ mol-1. The curium heat of extraction was performed under two sets of conditions and the obtained heats of extraction were in reasonable agreement with each other at -16.0 {+-} 1.1 and -16.8 {+-} 1.5 kJ mol-1.

  12. A calorimetric study of the hydrolysis and peroxide complex formation of the uranyl(VI) ion.

    PubMed

    Zanonato, Pier Luigi; Di Bernardo, Plinio; Grenthe, Ingmar

    2014-02-14

    The enthalpies of reaction for the formation of uranyl(vi) hydroxide {[(UO2)2(OH)2](2+), [(UO2)3(OH)4](2+), [(UO2)3(OH)5](+), [(UO2)3(OH)6](aq), [(UO2)3(OH)7](-), [(UO2)3(OH)8](2-), [(UO2)(OH)3](-), [(UO2)(OH)4](2-)} and peroxide complexes {[UO2(O2)(OH)](-) and [(UO2)2(O2)2(OH)](-)} have been determined from calorimetric titrations at 25 °C in a 0.100 M tetramethyl ammonium nitrate ionic medium. The hydroxide data have been used to test the consistency of the extensive thermodynamic database published by the Nuclear Energy Agency (I. Grenthe, J. Fuger, R. J. M. Konings, R. J. Lemire, A. B. Mueller, C. Nguyen-Trung and H. Wanner, Chemical Thermodynamics of Uranium, North-Holland, Amsterdam, 1992 and R. Guillaumont, T. Fanghänel, J. Fuger, I. Grenthe, V. Neck, D. J. Palmer and M. R. Rand, Update on the Chemical Thermodynamics of Uranium, Neptunium, Plutonium, Americium and Technetium, Elsevier, Amsterdam, 2003). A brief discussion is given about a possible structural relationship between the trinuclear complexes [(UO2)3(OH)n](6-n), n = 4-8. PMID:24301256

  13. Optical and Calorimetric Studies of Cholesterol-Rich Filamentous, Helical Ribbon and Crystal Microstructures

    SciTech Connect

    Miroshnikova, Y. A.; Elsenbeck, M.; Zastavker, Y. V.; Kashuri, K; Iannacchione, G. S.

    2009-04-19

    Formation of biological self-assemblies at all scales is a focus of studies in fields ranging from biology to physics to biomimetics. Understanding the physico-chemical properties of these self-assemblies may lead to the design of bio-inspired structures and technological applications. Here we examine self-assembled filamentous, helical ribbon, and crystal microstructures formed in chemically defined lipid concentrate (CDLC), a model system for cholesterol crystallization in gallbladder bile. CDLC consists of cholesterol, bilayer-forming amphiphiles, micelle-forming amphiphiles, and water. Phase contrast and differential interference contrast (DIC) microscopy indicate the presence of three microstructure types in all samples studied, and allow for an investigation of the structures' unique geometries. Additionally, confocal microscopy is used for qualitative assessment of surface and internal composition. To complement optical observations, calorimetric (differential-scanning and modulation) experiments, provide the basis for an in-depth understanding of collective and individual thermal behavior. Observed ''transition'' features indicate clustering and ''straightening'' of helical ribbons into short, increasingly thickening, filaments that dissolve with increasing temperature. These results suggest that all microstructures formed in CDLC may coexist in a metastable chemical equilibrium. Further investigation of the CDLC thermal profile should uncover the process of cholesterol crystallization as well as the unique design and function of microstructures formed in this system.

  14. Calorimetric studies of the ammonia-water system with application to the outer solar system

    NASA Astrophysics Data System (ADS)

    Yarger, J.; Lunine, J. I.; Burke, M.

    1993-07-01

    A series of heating experiments was performed on the condensed ammonia-water system using a differential scanning calorimeter (DSC). The water-rich samples were cooled quickly to below 130 K, then heated at a variety of rates. Rather than a single peritectic melt at 176 K, expected for the equilibrium system of water ice and ammonia dihydrate, four enthalpic transitions were repeatedly seen in the temperature range 150-176 K. These transitions are generally consistent with the earlier calorimetric results of Van Kasteren (1973), who interpreted the lowest temperature exotherm as crystallization of an amorphous ammonia-water compound formed during cooling. We propose that both sets of experiments are seeing the crystallization of ammonia monohydrate, which is metastable relative to the dihydrate, followed by partial remelting and crystallization of dihydrate upon further heating. The apparent stability of the monohydrate in the dihydrate equilibrium field implies a potentially complex behavior of ammonia-water ices in satellites. Possible self-heating of the mixture by several tens of degrees up to the 170 K eutectic could make mobilization of ammonia-water liquids in icy satellite interiors energetically easier than previously thought.

  15. Calorimetric measurement of electron energy deposition in extended media. Theory vs experiment

    SciTech Connect

    Lockwood, G.J.; Ruggles, L.E.; Miller, G.H.; Halbleib, J.A.

    1980-01-01

    A new calorimetric technique has been developed for measuring electron energy deposition profiles in one dimension. The experimental procedures and theoretical analyses required in the application of the new method are reviewed. Extensive results are presented for electron energy deposition profiles in semi-infinite homogeneous and multilayer configurations. These data cover a range of elements from beryllium through uranium at source energies from 0.3 to 1.0 MeV (selected data at 0.5 and 0.1 MeV) and at incident angles from 0/sup 0/ to 60/sup 0/. In every case, the experimental profiles are compared with the predictions of a coupled electron/photon Monte Carlo transport code. Overall agreement between theory and experiment is very good. However, there appears to be a tendency for the theoretical profiles to be higher near the peaks and lower near the tails, especially in high-Z materials. There is also a discrepancy between theory and experiment in low-Z materials near high-Z/low-Z interfaces.

  16. Electron energy and charge albedos - calorimetric measurement vs Monte Carlo theory

    SciTech Connect

    Lockwood, G.J.; Ruggles, L.E.; Miller, G.H.; Halbleib, J.A.

    1981-11-01

    A new calorimetric method has been employed to obtain saturated electron energy albedos for Be, C, Al, Ti, Mo, Ta, U, and UO/sub 2/ over the range of incident energies from 0.1 to 1.0 MeV. The technique was so designed to permit the simultaneous measurement of saturated charge albedos. In the cases of C, Al, Ta, and U the measurements were extended down to about 0.025 MeV. The angle of incidence was varied from 0/sup 0/ (normal) to 75/sup 0/ in steps of 15/sup 0/, with selected measurements at 82.5/sup 0/ in Be and C. In each case, state-of-the-art predictions were obtained from a Monte Carlo model. The generally good agreement between theory and experiment over this extensive parameter space represents a strong validation of both the theoretical model and the new experimental method. Nevertheless, certain discrepancies at low incident energies, especially in high-atomic-number materials, and at all energies in the case of the U energy albedos are not completely understood.

  17. Algorithms for Identification of Nearly-Coincident Events in Calorimetric Sensors

    NASA Astrophysics Data System (ADS)

    Alpert, B.; Ferri, E.; Bennett, D.; Faverzani, M.; Fowler, J.; Giachero, A.; Hays-Wehle, J.; Maino, M.; Nucciotti, A.; Puiu, A.; Swetz, D.; Ullom, J.

    2015-12-01

    For experiments with high arrival rates, reliable identification of nearly-coincident events can be crucial. For calorimetric measurements to directly measure the neutrino mass such as HOLMES, unidentified pulse pile-ups are expected to be a leading source of experimental error. Although Wiener filtering can be used to recognize pile-up, it suffers from errors due to pulse shape variation from detector nonlinearity, readout dependence on subsample arrival times, and stability issues from the ill-posed deconvolution problem of recovering Dirac delta-functions from smooth data. Due to these factors, we have developed a processing method that exploits singular value decomposition to (1) separate single-pulse records from piled-up records in training data and (2) construct a model of single-pulse records that accounts for varying pulse shape with amplitude, arrival time, and baseline level, suitable for detecting nearly-coincident events. We show that the resulting processing advances can reduce the required performance specifications of the detectors and readout system or, equivalently, enable larger sensor arrays and better constraints on the neutrino mass.

  18. The CALorimetric Electron Telescope (CALET) for high-energy astroparticle physics on the International Space Station

    NASA Astrophysics Data System (ADS)

    Adriani, O.; Akaike, Y.; Asano, K.; Asaoka, Y.; Bagliesi, M. G.; Bigongiari, G.; Binns, W. R.; Bonechi, S.; Bongi, M.; Buckley, J. H.; Castellini, G.; Cherry, M. L.; Collazuol, G.; Ebisawa, K.; Di Felice, V.; Fuke, H.; Guzik, T. G.; Hams, T.; Hareyama, M.; Hasebe, N.; Hibino, K.; Ichimura, M.; Ioka, K.; Israel, M. H.; Javaid, A.; Kamioka, E.; Kasahara, K.; Kataoka, J.; Kataoka, R.; Katayose, Y.; Kawanaka, N.; Kitamura, H.; Kotani, T.; Krawczynski, H. S.; Krizmanic, J. F.; Kubota, A.; Kuramata, S.; Lomtadze, T.; Maestro, P.; Marcelli, L.; Marrocchesi, P. S.; Mitchell, J. W.; Miyake, S.; Mizutani, K.; Moiseev, A. A.; Mori, K.; Mori, M.; Mori, N.; Motz, H. M.; Munakata, K.; Murakami, H.; Nakagawa, Y. E.; Nakahira, S.; Nishimura, J.; Okuno, S.; Ormes, J. F.; Ozawa, S.; Palma, F.; Papini, P.; Rauch, B. F.; Ricciarini, S. B.; Sakamoto, T.; Sasaki, M.; Shibata, M.; Shimizu, Y.; Shiomi, A.; Sparvoli, R.; Spillantini, P.; Takahashi, I.; Takayanagi, M.; Takita, M.; Tamura, T.; Tateyama, N.; Terasawa, T.; Tomida, H.; Torii, S.; Tunesada, Y.; Uchihori, Y.; Ueno, S.; Vannuccini, E.; Wefel, J. P.; Yamaoka, K.; Yanagita, S.; Yoshida, A.; Yoshida, K.; Yuda, T.

    2015-08-01

    The CALorimetric Electron Telescope (CALET) is a space experiment, currently under development by Japan in collaboration with Italy and the United States, which will measure the flux of cosmic-ray electrons (and positrons) up to 20 TeV energy, of gamma rays up to 10 TeV, of nuclei with Z from 1 to 40 up to 1 PeV energy, and will detect gamma-ray bursts in the 7 keV to 20 MeV energy range during a 5 year mission. These measurements are essential to investigate possible nearby astrophysical sources of high energy electrons, study the details of galactic particle propagation and search for dark matter signatures. The main detector of CALET, the Calorimeter, consists of a module to identify the particle charge, followed by a thin imaging calorimeter (3 radiation lengths) with tungsten plates interleaving scintillating fibre planes, and a thick energy measuring calorimeter (27 radiation lengths) composed of lead tungstate logs. The Calorimeter has the depth, imaging capabilities and energy resolution necessary for excellent separation between hadrons, electrons and gamma rays. The instrument is currently being prepared for launch (expected in 2015) to the International Space Station ISS, for installation on the Japanese Experiment Module - Exposure Facility (JEM-EF).

  19. The CALorimetric Electron Telescope (CALET) for high-energy astroparticle physics on the International Space Station

    NASA Astrophysics Data System (ADS)

    Adriani, O.; Akaike, Y.; Asano, K.; Asaoka, Y.; Bagliesi, M. G.; Bigongiari, G.; Binns, W. R.; Bonechi, S.; Bongi, M.; Buckley, J. H.; Castellini, G.; Cherry, M. L.; Collazuol, G.; Ebisawa, K.; Di Felice, V.; Fuke, H.; Guzik, T. G.; Hams, T.; Hareyama, M.; Hasebe, N.; Hibino, K.; Ichimura, M.; Ioka, K.; Israel, M. H.; Javaid, A.; Kamioka, E.; Kasahara, K.; Kataoka, J.; Kataoka, R.; Katayose, Y.; Kawanaka, N.; Kitamura, H.; Kotani, T.; Krawczynski, H. S.; Krizmanic, J. F.; Kubota, A.; Kuramata, S.; Lomtadze, T.; Maestro, P.; Marcelli, L.; Marrocchesi, P. S.; Mitchell, J. W.; Miyake, S.; Mizutani, K.; Moiseev, A. A.; Mori, K.; Mori, M.; Mori, N.; Motz, H. M.; Munakata, K.; Murakami, H.; Nakagawa, Y. E.; Nakahira, S.; Nishimura, J.; Okuno, S.; Ormes, J. F.; Ozawa, S.; Palma, F.; Papini, P.; Rauch, B. F.; Ricciarini, S. B.; Sakamoto, T.; Sasaki, M.; Shibata, M.; Shimizu, Y.; Shiomi, A.; Sparvoli, R.; Spillantini, P.; Takahashi, I.; Takayanagi, M.; Takita, M.; Tamura, T.; Tateyama, N.; Terasawa, T.; Tomida, H.; Torii, S.; Tunesada, Y.; Uchihori, Y.; Ueno, S.; Vannuccini, E.; Wefel, J. P.; Yamaoka, K.; Yanagita, S.; Yoshida, A.; Yoshida, K.; Yuda, T.

    2015-05-01

    The CALorimetric Electron Telescope (CALET) is a space experiment, currently under development by Japan in collaboration with Italy and the United States, which will measure the flux of cosmic-ray electrons (and positrons) up to 20 TeV energy, of gamma rays up to 10 TeV, of nuclei with Z from 1 to 40 up to 1 PeV energy, and will detect gamma-ray bursts in the 7 keV to 20 MeV energy range during a 5 year mission. These measurements are essential to investigate possible nearby astrophysical sources of high energy electrons, study the details of galactic particle propagation and search for dark matter signatures. The main detector of CALET, the Calorimeter, consists of a module to identify the particle charge, followed by a thin imaging calorimeter (3 radiation lengths) with tungsten plates interleaving scintillating fibre planes, and a thick energy measuring calorimeter (27 radiation lengths) composed of lead tungstate logs. The Calorimeter has the depth, imaging capabilities and energy resolution necessary for excellent separation between hadrons, electrons and gamma rays. The instrument is currently being prepared for launch (expected in 2015) to the International Space Station ISS, for installation on the Japanese Experiment Module - Exposure Facility (JEM-EF).

  20. Algorithms for Identification of Nearly-Coincident Events in Calorimetric Sensors

    NASA Astrophysics Data System (ADS)

    Alpert, B.; Ferri, E.; Bennett, D.; Faverzani, M.; Fowler, J.; Giachero, A.; Hays-Wehle, J.; Maino, M.; Nucciotti, A.; Puiu, A.; Swetz, D.; Ullom, J.

    2016-07-01

    For experiments with high arrival rates, reliable identification of nearly-coincident events can be crucial. For calorimetric measurements to directly measure the neutrino mass such as HOLMES, unidentified pulse pile-ups are expected to be a leading source of experimental error. Although Wiener filtering can be used to recognize pile-up, it suffers from errors due to pulse shape variation from detector nonlinearity, readout dependence on subsample arrival times, and stability issues from the ill-posed deconvolution problem of recovering Dirac delta-functions from smooth data. Due to these factors, we have developed a processing method that exploits singular value decomposition to (1) separate single-pulse records from piled-up records in training data and (2) construct a model of single-pulse records that accounts for varying pulse shape with amplitude, arrival time, and baseline level, suitable for detecting nearly-coincident events. We show that the resulting processing advances can reduce the required performance specifications of the detectors and readout system or, equivalently, enable larger sensor arrays and better constraints on the neutrino mass.

  1. Effect of sulfoxides on the thermal denaturation of hen lysozyme: A calorimetric and Raman study

    NASA Astrophysics Data System (ADS)

    Torreggiani, A.; Di Foggia, M.; Manco, I.; De Maio, A.; Markarian, S. A.; Bonora, S.

    2008-11-01

    A multidisciplinary study of the thermal denaturation of lysozyme in the presence of three sulfoxides with different length in hydrocarbon chain (DMSO, DESO, and DPSO) was carried out by means of DSC, Raman spectroscopy, and SDS-PAGE techniques. In particular, the Td and Δ H values obtained from the calorimetric measurements showed that lysozyme is partially unfolded by sulfoxides but most of the conformation holds native state. The sulfoxide denaturing ability increases in the order DPSO > DESO > DMSO. Moreover, only DMSO and DESO have a real effect in preventing the heat-induced inactivation of the protein and their maximum heat-protective ability is reached when the DMSO and DESO amount is ⩾25% w/w. The sulfoxide ability to act as effective protective agents against the heat-induced inactivation was confirmed by the protein analysis. The enzymatic activity, as well as the SDS-PAGE analysis, suggested that DESO, having a low hydrophobic character and a great ability to stabilise the three-dimensional water structure, is the most heat-protective sulfoxide. An accurate evaluation of the heat-induced conformational changes of the lysozyme structure before and after sulfoxide addition was obtained by the analysis of the Raman spectra. The addition of DMSO or DESO in low concentration resulted to sensitively decrease the heat-induced structural modifications of the protein.

  2. Characterization of commercial Li-ion batteries using electrochemical-calorimetric measurements

    NASA Astrophysics Data System (ADS)

    Al Hallaj, S.; Prakash, J.; Selman, J. R.

    Commercial Li-ion cells of Type 18650 dimensions and prismatic designs from different manufacturers have been tested to evaluate their performance and to study their thermal behavior using electrochemical-calorimetric methods. All cells tested in this work showed good performance and cyclability under normal operating conditions. The measured heat effect for the cells were exothermic during discharge and partially endothermic during charge. Cell impedance was measured for selected cells and showed some dependence on the state of charge or depth of discharge, with significant increase at the end of discharge due to concentration polarization. The entropy coefficient (d Eeq/d T) for the A&T (18650) and Panasonic (CGR 18650) cells were measured using potentiometric methods at different depths of discharge (DOD). The measured values for both cells showed some dependence on the DOD with some perturbation near 4.0 V, where the measured d Eeq/d T for Panasonic cell had an unexpected positive value. This was found to be consistent with the measured endothermic heat effect during discharge for the Panasonic cell near Eeq=4.0 V. This may be related to a phase change in the LiCoO 2 cathode material, as reported in the literature, and to structural transformation in the graphite used as anode material, in the Panasonic cell.

  3. Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids

    SciTech Connect

    Kabadi, V.N.

    1990-01-01

    A model for phase equilibria of coal derived liquids is to be extended to include calorimetric properties as well. To accomplish this satisfactorily, the proposed work includes three tasks: (1) Refinement of the characterization procedure to include distribution of sulfur, oxygen, and nitrogen heteroatoms in coal liquids; (2) Measurement of high temperature (up to 400{degrees}C) and high pressure (up to 1000 psi) VLE data for binary systems of selected model compounds; and (3) Development of the thermodynamic model. The final product will include a computer program which with measurable properties of coal liquids as input, will give results for phase coexistence properties and excess enthalpies in the liquid phase. Efforts are continuing to apply the new thermodynamic model for VLE and enthalpy predictions for coal liquids by the methods of continuous thermodynamics. Recently, Thompson, Brobst and Hankinson have developed an equation of state that represents compressibilities of liquids very well. The authors have undertaken the task of combining this equation of state with their thermodynamic model to provide a comprehensive model for high pressure liquid mixtures. Calibration and preliminary set-up procedure for the VLE apparatus with the new liquid level sensor have been completed. The apparatus is currently being tested with the binary system quinoline-tetralin. Chromatographic characterization work was delayed because of complexities of the calibration procedure and tedious calculations necessary for number average and weight average molecular weights. Results on the chromatographic studies are being deferred until computer software is received.

  4. The Calorimetric Electron Telescope (CALET) for High Energy Astroparticle Physics on the International Space Station

    NASA Astrophysics Data System (ADS)

    Torii, Shoji

    The Calorimetric Electron Telescope, CALET, space experiment, currently under development by Japan in collaboration with Italy and the United States, will measure the flux of Cosmic Ray electrons (and positrons) t o 20 TeV, gamma rays to 10 TeV , nuclei with Z=1 to 40 up to 1,000 TeV, and Gamma-ray bursts in the 7 keV- 10 MeV energy range during a five year mission. These measurements are essential to investigate possible nearby astrophysical sources of high energy electrons, study the details of galactic particle propagation and search for dark matter signatures. The main detector of Calet, the Calorimeter, consists of a module to identify the particle charge, followed by a thin imaging calorimeter (3 radiation lengths) with tungsten plates interleaving scintillating fiber planes, and a thick energy measuring calorimeter (27 radiation lengths) composed of lead tungstate logs. The Calorimeter has the depth, imaging capabilities and energy resolution necessary for excellent separation between hadrons, electrons and gamma rays. The instrument is currently being prepared for launch, during the Japan Fiscal Year (April, 2014- March, 2015) time frame, to the International Space Station (ISS) for installation on the Japanese Experiment Module - Exposure Facility (JEM-EF).

  5. Status and performance of the CALorimetric Electron Telescope (CALET) on the International Space Station

    NASA Astrophysics Data System (ADS)

    Adriani, O.; Akaike, Y.; Asaoka, Y.; Asano, K.; Bagliesi, M. G.; Bigongiari, G.; Binns, W. R.; Bongi, M.; Buckley, J. H.; Cassese, A.; Castellini, G.; Cherry, M. L.; Collazuol, G.; Ebisawa, K.; Di Felice, V.; Fuke, H.; Guzik, T. G.; Hams, T.; Hasebe, N.; Hareyama, M.; Hibino, K.; Ichimura, M.; Ioka, K.; Israel, M. H.; Javaid, A.; Kamioka, E.; Kasahara, K.; Katayose, Y.; Kataoka, J.; Kataoka, R.; Kawanaka, N.; Kitamura, H.; Kotani, T.; Krawczynski, H. S.; Krizmanic, J. F.; Kubota, A.; Kuramata, S.; Lomtadze, T.; Maestro, P.; Marcelli, L.; Marrocchesi, P. S.; Mitchell, J. W.; Miyake, S.; Mizutani, K.; Motz, H. M.; Moiseev, A. A.; Mori, K.; Mori, M.; Mori, N.; Munakata, K.; Murakami, H.; Nakagawa, Y. E.; Nakahira, S.; Nishimura, J.; Okuno, S.; Ormes, J. F.; Ozawa, S.; Palma, F.; Papini, P.; Rauch, B. F.; Ricciarini, S.; Sakamoto, T.; Sasaki, M.; Shibata, M.; Shimizu, Y.; Shiomi, A.; Sparvoli, R.; Spillantini, P.; Takahashi, I.; Takayanagi, M.; Takita, M.; Tamura, T.; Tateyama, N.; Terasawa, T.; Tomida, H.; Torii, S.; Tunesada, Y.; Uchihori, Y.; Ueno, S.; Vannuccini, E.; Wefel, J. P.; Yamaoka, K.; Yanagita, S.; Yoshida, A.; Yoshida, K.; Yuda, T.

    2014-11-01

    The CALorimetric Electron Telescope (CALET) space experiment, currently under development by Japan in collaboration with Italy and the United States, will measure the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV during a two-year mission on the International Space Station (ISS), extendable to five years. These measurements are essential to search for dark matter signatures, investigate the mechanism of cosmic-ray acceleration and propagation in the Galaxy and discover possible astrophysical sources of high-energy electrons nearby the Earth. The instrument consists of two layers of segmented plastic scintillators for the cosmic-ray charge identification (CHD), a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). CALET has sufficient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma rays. The instrument will be launched to the ISS within 2014 Japanese Fiscal Year (by the end of March 2015) and installed on the Japanese Experiment Module-Exposed Facility (JEM-EF). In this paper, we will review the status and main science goals of the mission and describe the instrument configuration and performance.

  6. Calorimetric studies of the ammonia-water system with application to the outer solar system

    NASA Technical Reports Server (NTRS)

    Yarger, Jeffery; Lunine, Jonathan I.; Burke, Michael

    1993-01-01

    A series of heating experiments was performed on the condensed ammonia-water system using a differential scanning calorimeter (DSC). The water-rich samples were cooled quickly to below 130 K, then heated at a variety of rates. Rather than a single peritectic melt at 176 K, expected for the equilibrium system of water ice and ammonia dihydrate, four enthalpic transitions were repeatedly seen in the temperature range 150-176 K. These transitions are generally consistent with the earlier calorimetric results of Van Kasteren (1973), who interpreted the lowest temperature exotherm as crystallization of an amorphous ammonia-water compound formed during cooling. We propose that both sets of experiments are seeing the crystallization of ammonia monohydrate, which is metastable relative to the dihydrate, followed by partial remelting and crystallization of dihydrate upon further heating. The apparent stability of the monohydrate in the dihydrate equilibrium field implies a potentially complex behavior of ammonia-water ices in satellites. Possible self-heating of the mixture by several tens of degrees up to the 170 K eutectic could make mobilization of ammonia-water liquids in icy satellite interiors energetically easier than previously thought.

  7. An IR and Calorimetric Investigation of the Structural, Crystal-Chemical and Thermodynamic Properties of Hydrogrossular

    NASA Astrophysics Data System (ADS)

    Geiger, C. A.; Dachs, E.

    2012-04-01

    their collective interactions measurably affect the lattice dynamic (i.e. thermodynamic) behavior. The low temperature heat capacity behavior was investigated with a commercially designed relaxation calorimeter between 5 and 300 K on a mg-sized sample. The heat capacity data are well behaved at T < 300 K and show a monotonic decrease in magnitude with decreasing temperature. A standard third-law entropy value of So = 421.7 ± 1.6 J/mol·K was calculated. Using this new calorimetric-based So value and published standard enthalpy of formation data for katoite, a calorimetric-based Gibbs free energy of formation at 298 K can be obtained as ΔG°f = -5021.2 kJ/mol. The Cp data show no evidence for any phase transition as possibly expected by the change in OH-mode behavior with decreasing temperature. We have no explanation for the appearance of the additional modes. It is worth noting that the katoite crystal structure in terms of lattice dynamic or thermodynamic behavior should be thought of having OH groups and not O4H4 clusters or polyhedral units as is often written in the literature. The single crystallographic OH group in katoite shows very weak, if any, hydrogen bonding and the H atoms have large amplitudes of vibration. The weak H bonding controls the nature of low energy OH-related vibrations and this leads to its large So value.

  8. Cri du Chat syndrome

    PubMed Central

    Cerruti Mainardi, Paola

    2006-01-01

    The Cri du Chat syndrome (CdCS) is a genetic disease resulting from a deletion of variable size occurring on the short arm of chromosome 5 (5p-). The incidence ranges from 1:15,000 to 1:50,000 live-born infants. The main clinical features are a high-pitched monochromatic cry, microcephaly, broad nasal bridge, epicanthal folds, micrognathia, abnormal dermatoglyphics, and severe psychomotor and mental retardation. Malformations, although not very frequent, may be present: cardiac, neurological and renal abnormalities, preauricular tags, syndactyly, hypospadias, and cryptorchidism. Molecular cytogenetic analysis has allowed a cytogenetic and phenotypic map of 5p to be defined, even if results from the studies reported up to now are not completely in agreement. Genotype-phenotype correlation studies showed a clinical and cytogenetic variability. The identification of phenotypic subsets associated with a specific size and type of deletion is of diagnostic and prognostic relevance. Specific growth and psychomotor development charts have been established. Two genes, Semaphorin F (SEMAF) and δ-catenin (CTNND2), which have been mapped to the "critical regions", are potentially involved in cerebral development and their deletion may be associated with mental retardation in CdCS patients. Deletion of the telomerase reverse transcriptase (hTERT) gene, localised to 5p15.33, could contribute to the phenotypic changes in CdCS. The critical regions were recently refined by using array comparative genomic hybridisation. The cat-like cry critical region was further narrowed using quantitative polymerase chain reaction (PCR) and three candidate genes were characterised in this region. The diagnosis is based on typical clinical manifestations. Karyotype analysis and, in doubtful cases, FISH analysis will confirm the diagnosis. There is no specific therapy for CdCS but early rehabilitative and educational interventions improve the prognosis and considerable progress has been made in

  9. Seasonal Variability in Calorimetric Energy Content of Two Caribbean Mesophotic Corals.

    PubMed

    Brandtneris, Viktor W; Brandt, Marilyn E; Glynn, Peter W; Gyory, Joanna; Smith, Tyler B

    2016-01-01

    Energetic responses of zooxanthellate reef corals along depth gradients have relevance to the refugia potential of mesophotic coral ecosystems (MCEs). Previous observations suggested that MCEs in the Caribbean are thermally buffered during the warmest parts of the year and occur within or just below the chlorophyll maximum, suggesting abundant trophic resources. However, it is not known if mesophotic corals can maintain constant energy needs throughout the year with changing environmental and biological conditions. The energetic content of tissues from the stony coral species Orbicella faveolata and Agaricia lamarcki was measured on the southern insular shelf of St. Thomas, US Virgin Islands (USVI), using micro-bomb calorimetry. Three sites for each species, at depths of 6m, 25m, 38m and 63m, were selected to capture energetic differences across the major vertical range extent of both species in the USVI-and sampled over five periods from April 2013 to April 2014. Mesophotic colonies of O. faveolata exhibited a significant reduction in energetic content during the month of September 2013 compared to mid-depth and shallow colonies (p = 0.032), whereas A. lamarcki experienced similar energetic variability, but with a significant reduction in energy content that occurred in July 2013 for colonies at sites deeper than 25m (p = 0.014). The results of calorimetric analyses indicate that O. faveolata may be at risk during late summer stress events, possibly due to the timing of reproductive activities. The low-point of A. lamarcki energy content, which may also coincide with reproduction, occurs prior to seasonal stress events, indicating contrasting, species-specific responses to environmental variability on MCEs. PMID:27050430

  10. Calorimetric Study of Magnetic Field-Induced Phase Transitions in - Fulvalenium) -

    NASA Astrophysics Data System (ADS)

    Fortune, Nathanael Alexander

    The particular class of organic conductors known as the Bechgaard salts exhibit a variety of highly anisotropic magnetic, thermal, and electrical phenomena. At low temperatures (below 10 kelvin), the application of a strong magnetic field establishes an effectively lower-dimensional anisotropic Fermi surface, as manifested in a variety of quasi one dimensional and quasi two dimensional thermodynamic and transport properties. Most dramatically, an increasing magnetic field--after suppression of superconductivity, induces a second order phase transition from a metallic to a spin density wave semimetal, followed by a series of first order phase transitions between density wave semimetallic states. This thesis concerns the thermodynamic nature of the low temperature magnetic field induced phase transitions in the Bechgaard charge-transfer salt (TMTSF)2-Cl(O)4. Presented here are the first measurements of the specific heat in magnetic fields up to 30 tesla, as well as the design and construction of a small sample calorimeter capable of operating at dilution refrigerator temperatures in the challenging environment of the high field resistive Bitter magnets. From transport measurements, the existence of a magnetic field induced reentrance into the metallic state has previously been inferred. In this thesis, the unambiguous bulk thermodynamic character of the reentrance is calorimetrically demonstrated. The behavior of the electronic specific heat at the reentrant transition is shown to be consistent with magnetic field enhanced localization. Additionally, quantum oscillations in the high field semimetallic state and the presence of additional structure above the reentrant field are observed. Although these oscillations have also been observed in magnetoresistance and magnetization, the magnitude of the oscillations in the specific heat calls into question all known models for the physical origin of these oscillations.

  11. Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids. Final technical report

    SciTech Connect

    Kabadi, V.N.

    1992-10-01

    The work on this project was initiated on September 1, 1989. The project consisted of three different tasks. 1. A thermodynamic model to predict VLE and calorimetric properties of coal liquids. 2. VLE measurements at high temperature and high pressure for coal model compounds and 3. Chromatographic characterization of coal liquids for distribution of heteroatoms. The thermodynamic model developed is an extension of the previous model developed for VLE of coal derived fluids (DOE Grant no. FG22-86PC90541). The model uses the modified UNIFAC correlation for the liquid phase. Some unavailable UNIFAC interactions parameters have been regressed from experimental VLE and excess enthalpy data. The model is successful in predicting binary VLE and excess enthalpy data. Further refinements of the model are suggested. An apparatus for the high pressure high temperature VLE data measurements has been built and tested. Tetralin-Quinoline is the first binary system selected for data measurements. The equipment was tested by measuring 325{degree}C isotherm for this system and comparing it with literature data. Additional isotherms at 350{degree}C and 370{degree}C have been measured. The framework for a characterization procedure for coal derived liquids has been developed. A coal liquid is defined by a true molecular weight distribution and distribution of heteroatoms as a function of molecular weights. Size exclusions liquid chromatography, elemental analysis and FTIR spectroscopy methods are used to obtain the molecular weight and hetroatom distributions. Further work in this area should include refinements of the characterization procedure, high temperature high pressure VLE data measurements for selective model compound binary systems, and improvement of the thermodynamic model using the new measured data and consistent with the developments in the characterization procedure.

  12. Calorimetric measurement of afterheat in target materials for the accelerator production of tritium

    SciTech Connect

    Perry, R.B.; Zucker, M.S.

    1994-06-01

    The estimate of afterheat in a spallation target of lead (Pb) or tungsten (W), by calorimetry, is the purpose of this experiment in support of the Accelerator Production of Tritium (APT). Such measurements are needed to confirm code calculations, these being the only practical way of gaining this type of information in a form suitable to aid the design of the APT machine. Knowledge of the magnitude and duration of afterheat resulting from decay of activation products produced by proton bombardment of the target is necessary to quantify APT safety assumptions, to design target cooling and safety systems, and to reduce technical risk. Direct calorimetric measurement of the afterheat for the appropriate incident proton energies is more reliable than the available alternative, which is indirect, based on data from gamma-ray spectroscopy measurements. The basic concept, a direct measurement of decay afterheat which bypasses the laborious classical way of determining this quantity, has been demonstrated to work. The gamma-ray energy given off by the decay products produced in the activation of lead or tungsten with high-energy protons apparently does represent a significant fraction of the total decay energy. A calorimeter designed for measurement of isotopes decaying by alpha emission must be modified to reduce energy lost with escaping gamma rays. Replacement of the aluminum liner with a tungsten liner in the SSC measurement chamber resulted in a 270% increase in measured heat, proving that the energy loss in the earlier (1992) measurements was significant. Gamma-ray measurements are needed to confirm the gamma-ray absorption calculations for the calorimeter to determine the correction for loss of heat due to transmission of high-energy gamma rays through the calorimeter walls. The experiments at BLIP have shown that calorimetry can be a useful tool in measuring the afterheat in APT target materials.

  13. Calorimetric studies of the kinetic unfreezing of molecular motions in hydrated lysozyme, hemoglobin, and myoglobin.

    PubMed Central

    Sartor, G; Mayer, E; Johari, G P

    1994-01-01

    Differential scanning calorimetric (DSC) studies of the glassy states of as-received and hydrated lysozyme, hemoglobin, and myoglobin powders, with water contents of < or = 0.25, < or = 0.30, and < or = 0.29 g/g of protein, show that their heat capacity slowly increases with increasing temperature, without showing an abrupt increase characteristic of glass-->liquid transition. Annealing (also referred to as physical aging) of the hydrated proteins causes their DSC scans to show an endothermic region, similar to an overshoot, immediately above the annealing temperature. This annealing effect appears at all temperatures between approximately 150 and 300 K. The area under these peaks increases with increasing annealing time at a fixed temperature. The effects are attributed to the presence of a large number of local structures in which macromolecular segments diffuse at different time scales over a broad range. The lowest time scale corresponds to the > N-H and -O-H group motions which become kinetically unfrozen at approximately 150-170 K on heating at a rate of 30 K min-1 and which have a relaxation time of 5-10 s in this temperature range. The annealing effects confirm that the individual glass transition of the relaxing local regions is spread over a temperature range up to the denaturation temperature region of the proteins. The interpretation is supported by simulation of DSC scans in which the distribution of relaxation times is assumed to be exceptionally broad and in which annealing done at several temperatures over a wide range produces endothermic effects (or regions of DSC scans) qualitatively similar to those observed for the hydrated proteins. PMID:8130342

  14. Seasonal Variability in Calorimetric Energy Content of Two Caribbean Mesophotic Corals

    PubMed Central

    Brandtneris, Viktor W.; Brandt, Marilyn E.; Glynn, Peter W.; Gyory, Joanna; Smith, Tyler B.

    2016-01-01

    Energetic responses of zooxanthellate reef corals along depth gradients have relevance to the refugia potential of mesophotic coral ecosystems (MCEs). Previous observations suggested that MCEs in the Caribbean are thermally buffered during the warmest parts of the year and occur within or just below the chlorophyll maximum, suggesting abundant trophic resources. However, it is not known if mesophotic corals can maintain constant energy needs throughout the year with changing environmental and biological conditions. The energetic content of tissues from the stony coral species Orbicella faveolata and Agaricia lamarcki was measured on the southern insular shelf of St. Thomas, US Virgin Islands (USVI), using micro-bomb calorimetry. Three sites for each species, at depths of 6m, 25m, 38m and 63m, were selected to capture energetic differences across the major vertical range extent of both species in the USVI—and sampled over five periods from April 2013 to April 2014. Mesophotic colonies of O. faveolata exhibited a significant reduction in energetic content during the month of September 2013 compared to mid-depth and shallow colonies (p = 0.032), whereas A. lamarcki experienced similar energetic variability, but with a significant reduction in energy content that occurred in July 2013 for colonies at sites deeper than 25m (p = 0.014). The results of calorimetric analyses indicate that O. faveolata may be at risk during late summer stress events, possibly due to the timing of reproductive activities. The low-point of A. lamarcki energy content, which may also coincide with reproduction, occurs prior to seasonal stress events, indicating contrasting, species-specific responses to environmental variability on MCEs. PMID:27050430

  15. L'Aventure du LHC

    ScienceCinema

    None

    2011-10-06

    Cette présentation s?adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l?engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

  16. L'Aventure du LHC

    SciTech Connect

    2010-06-11

    Cette présentation s’adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l’engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

  17. Investigation of ferroelectric phase transitions of water in nanoporous silicates in simultaneous electrical noise and calorimetric measurements

    NASA Astrophysics Data System (ADS)

    Bordonskiy, G. S.; Orlov, A. O.

    2014-08-01

    The phase transitions of water in the nanoporous silicate materials SBA-15 and MCM-41 with an ordered system of cylindrical pores have been investigated. Measurements of low-frequency electrical noises (Barkhausen noises) in the frequency range of 1-100 Hz have been performed simultaneously with relative calorimetric measurements. It has been found that the voltage of electrical fluctuations increases approximately 100 times in the temperature range from -30 to -50°C, which is associated with the first-order and second-order ferroelectric phase transitions. It has been assumed that the ferroelectric ice XI can be formed in capillary pores of the materials under investigations.

  18. Analbite - Sanidine Thermodynamic Mixing Properties: Highly Precise HF Solution Calorimetric Data Across A Twenty-Member Crystalline Solution Series

    NASA Astrophysics Data System (ADS)

    Hovis, G. L.

    2013-12-01

    Enthalpies of K-Na mixing for the analbite - sanidine feldspar series were investigated by Hovis (1988, J. Petrology) in the early 80's. That work was based on data at a limited number of compositions, owing to the large sample sizes required for HF solution calorimetric measurements at the time. Thermodynamic mixing properties for mineral series, especially those exhibiting compositionally asymmetric mixing quantities, are best defined when samples at a large number of compositions are utilized. Enabled by the small sample sizes now possible for HF solution calorimetric dissolutions (Hovis et al., 1998, Amer. Mineral.), we revisit feldspar thermodynamic properties, having synthesized an analbite - sanidine series consisting of samples at 20 compositions. Solution calorimetric experiments on these samples at 50 °C in 20.1 wt% HF under isoperibolic conditions have resulted in highly precise calorimetric data (standard deviation per sample averaging 0.06 % of the heat of solution). Although enthalpies of K-Na mixing based on the new data display some degree of compositional asymmetry, with a maximum value of 4.8 kJ/mol at a mole fraction potassium of 0.47, the distribution of enthalpy-of-mixing values remains nearly symmetric with respect to K content. This contrasts significantly with data for Al-Si ordered low albite - microcline crystalline solutions, reinvestigated via synthesis of a 21-member series, which show significantly higher mixing magnitudes and considerably greater asymmetry with respect to composition. The maximization of enthalpies of K-Na mixing at sodic compositions correlates well with the sodic critical compositions for both solvi. The lower mixing magnitudes for analbite - sanidine are consistent with the comparatively lower critical temperature of the analbite - sanidine solvus (e.g., Smith & Parsons, 1974, Mineral. Mag.) relative to that for low albite - microcline (Bachinski & Müller, 1971, J. Petrology). Entropies of K-Na mixing for

  19. Analbite - Sanidine Thermodynamic Mixing Properties: Highly Precise HF Solution Calorimetric Data Across A Twenty-Member Crystalline Solution Series

    NASA Astrophysics Data System (ADS)

    Hovis, G. L.

    2012-12-01

    Enthalpies of K-Na mixing for the analbite - sanidine feldspar series were investigated by Hovis (1988, J. Petrology) in the early 80's. That work was based on data at a limited number of compositions, owing to the large sample sizes required for HF solution calorimetric measurements at the time. Thermodynamic mixing properties for mineral series, especially those exhibiting compositionally asymmetric mixing quantities, are best defined when samples at a large number of compositions are utilized. Enabled by the small sample sizes now possible for HF solution calorimetric dissolutions (Hovis et al., 1998, Amer. Mineral.), we revisit feldspar thermodynamic properties, having synthesized an analbite - sanidine series consisting of samples at 20 compositions. Solution calorimetric experiments on these samples at 50 °C in 20.1 wt% HF under isoperibolic conditions have resulted in highly precise calorimetric data (standard deviation per sample averaging 0.06 % of the heat of solution). Although enthalpies of K-Na mixing based on the new data display some degree of compositional asymmetry, with a maximum value of 4.8 kJ/mol at a mole fraction potassium of 0.47, the distribution of enthalpy-of-mixing values remains nearly symmetric with respect to K content. This contrasts significantly with data for Al-Si ordered low albite - microcline crystalline solutions, reinvestigated via synthesis of a 21-member series, which show significantly higher mixing magnitudes and considerably greater asymmetry with respect to composition. The maximization of enthalpies of K-Na mixing at sodic compositions correlates well with the sodic critical compositions for both solvi. The lower mixing magnitudes for analbite - sanidine are consistent with the comparatively lower critical temperature of the analbite - sanidine solvus (e.g., Smith & Parsons, 1974, Mineral. Mag.) relative to that for low albite - microcline (Bachinski & Müller, 1971, J. Petrology). Entropies of K-Na mixing for

  20. Calorimetric and spectroscopic studies of aminoglycoside binding to AT-rich DNA triple helices

    PubMed Central

    Xi, Hongjuan; Kumar, Sunil; Dosen-Micovic, Ljiljana; Arya, Dev P.

    2013-01-01

    Calorimetric and fluorescence techniques were used to characterize the binding of aminoglycosides-neomycin, paromomycin, and ribostamycin, with 5′-dA12-x-dT12-x-dT12-3′ intramolecular DNA triplex (x = hexaethylene glycol) and poly(dA).2poly(dT) triplex. Our results demonstrate the following features: (1) UV thermal analysis reveals that the Tm for triplex decreases with increasing pH value in the presence of neomycin, while the Tm for the duplex remains unchanged. (2) The binding affinity of neomycin decreases with increased pH, although there is an increase in observed binding enthalpy. (3) ITC studies conducted in two buffers (sodium cacodylate and MOPS) yield the number of protonated drug amino groups (Δn) as 0.29 and 0.40 for neomycin and paromomycin interaction with 5′-dA12-x-dT12-x-dT12-3′, respectively. (4) The specific heat capacity change (ΔCp) determined by ITC studies is negative, with more negative values at lower salt concentrations. From 100 mM to 250 mM KCl, the ΔCp ranges from −402 to −60 cal/(mol K) for neomycin. At pH 5.5, a more positive ΔCp is observed, with a value of −98 cal/(mol K) at 100 mM KCl. ΔCp is not significantly affected by ionic strength. (5) Salt dependence studies reveal that there are at least three amino groups of neomycin participating in the electrostatic interactions with the triplex. (6) FID studies using thiazole orange were used to derive the AC50 (aminoglycoside concentration needed to displace 50% of the dye from the triplex) values. Neomycin shows a seven fold higher affinity than paromomycin and eleven fold higher affinity than ribostamycin at pH 6.8. (7) Modeling studies, consistent with UV and ITC results, show the importance of an additional positive charge in triplex recognition by neomycin. The modeling and thermodynamic studies indicate that neomycin binding to the DNA triplex depends upon significant contributions from charge as well as shape complementarity of the drug to the DNA triplex

  1. Investigation of a zirconia co-fired ceramic calorimetric microsensor for high-temperature flow measurements

    NASA Astrophysics Data System (ADS)

    Lekholm, Ville; Persson, Anders; Klintberg, Lena; Thornell, Greger

    2015-06-01

    This paper describes the design, fabrication and characterization of a flow sensor for high-temperature, or otherwise aggressive, environments, like, e.g. the propulsion system of a small spacecraft. The sensor was fabricated using 8 mol% yttria stabilized zirconia (YSZ8) high-temperature co-fired ceramic (HTCC) tape and screen printed platinum paste. A calorimetric flow sensor design was used, with five 80 µm wide conductors, separated by 160 µm, in a 0.4 mm wide, 0.1 mm deep and 12.5 mm long flow channel. The central conductor was used as a heater for the sensor, and the two adjacent conductors were used to resistively measure the heat transferred from the heater by forced convection. The two outermost conductors were used to study the influence of an auxiliary heat source on the sensor. The resistances of the sensor conductors were measured using four-point connections, as the gas flow rate was slowly increased from 0 to 40 sccm, with different power supplied through the central heater, as well as with an upstream or downstream heater powered. In this study, the thermal and electrical integrability of microcomponents on the YSZ8 substrate was of particular interest and, hence, the influence of thermal and ionic conduction in the substrate was studied in detail. The effect of the ion conductivity of YSZ8 was studied by measuring the resistance of a platinum conductor and the resistance between two adjacent conductors on YSZ8, in a furnace at temperatures from 20 to 930 °C and by measuring the resistance with increasing current through a conductor. With this design, the influence of ion conductivity through the substrate became apparent above 700 °C. The sensitivity of the sensor was up to 1 mΩ sccm-1 in a range of 0-10 sccm. The results show that the signal from the sensor is influenced by the integrated auxiliary heating conductors and that these auxiliary heaters provide a way to balance disturbing heat sources, e.g. thrusters or other electronics, in

  2. Development of Metallic Magnetic Calorimeters for High Precision Measurements of Calorimetric Re-187 and Ho-163 Spectra

    NASA Technical Reports Server (NTRS)

    Ranitzsch, P. C.-O.; Porst, J.-P.; Kempf, S.; Pies, C.; Schafer, S.; Hengstler, D.; Fleischmann, A.; Enss, C.; Gastaldo, L.

    2012-01-01

    The measurement of calorimetric spectra following atomic weak decays, beta (b) and electron capture (EC), of nuclides having a very low Q-value, can provide an impressively high sensitivity to a non-vanishing neutrino mass. The achievable sensitivity in this kind of experiments is directly connected to the performance of the used detectors. In particular an energy resolution of a few eV and a pulse formation time well below 1 microsecond are required. Low temperature Metallic Magnetic Calorimeters (MMCs) for soft X-rays have already shown an energy resolution of 2.0 eV FWHM and a pulse rise-time of about 90 ns for fully micro-fabricated detectors. We present the use of MMCs for high precision measurements of calorimetric spectra following the beta-decay of Re-187 and the EC of Ho-163. We show results obtained with detectors optimized for Re-187 and for Ho-163 experiments respectively. While the detectors equipped with superconducting Re absorbers have not yet reached the aimed performance, a first detector prototype with a Au absorber having implanted Ho-163 ions already shows excellent results. An energy resolution of 12 eV FWHM and a rise time of 90 ns were measured.

  3. Urea-induced dissociation and unfolding of dodecameric glutamine synthetase from Escherichia coli: calorimetric and spectral studies.

    PubMed Central

    Zolkiewski, M.; Nosworthy, N. J.; Ginsburg, A.

    1995-01-01

    Urea-induced dissociation and unfolding of manganese.glutamine synthetase (Mn.GS) have been studied at 37 degrees C (pH 7) by spectroscopic and calorimetric methods. In 0 to approximately 2 M urea, Mn.GS retains its dodecameric structure and full catalytic activity. Mn.GS is dissociated into subunits in 6 M urea, as evidenced by a 12-fold decrease in 90 degrees light scattering and a monomer molecular weight of 51,800 in sedimentation equilibrium studies. The light scattering decrease in 4 M urea parallels the time course of Trp exposure but occurs more rapidly than changes in secondary structure and Tyr exposure. Early and late kinetic steps appear to involve predominantly disruption of intra-ring and inter-ring subunit contacts, respectively, in the layered hexagonal structure of Mn.GS. The enthalpies for transferring Mn.GS into urea solutions have been measured by titration calorimetry. After correcting for the enthalpy of binding urea to the protein, the enthalpy of dissociation and unfolding of Mn.GS is 14 +/- 4 cal/g. A net proton uptake of approximately 50 H+/dodecamer accompanies unfolding reactions. The calorimetric data are consistent with urea binding to multiple, independent sites in Mn.GS and the number of binding sites increasing approximately 9-fold during the protein unfolding. PMID:8520480

  4. Thermogravimetric and calorimetric characteristics during co-pyrolysis of municipal solid waste components.

    PubMed

    Ansah, Emmanuel; Wang, Lijun; Shahbazi, Abolghasem

    2016-10-01

    The thermogravimetric and calorimetric characteristics during pyrolysis of wood, paper, textile and polyethylene terephthalate (PET) plastic in municipal solid wastes (MSW), and co-pyrolysis of biomass-derived and plastic components with and without torrefaction were investigated. The active pyrolysis of the PET plastic occurred at a much higher temperature range between 360°C and 480°C than 220-380°C for the biomass derived components. The plastic pyrolyzed at a heating rate of 10°C/min had the highest maximum weight loss rate of 18.5wt%/min occurred at 420°C, followed by 10.8wt%/min at 340°C for both paper and textile, and 9.9wt%/min at 360°C for wood. At the end of the active pyrolysis stage, the final mass of paper, wood, textile and PET was 28.77%, 26.78%, 21.62% and 18.31%, respectively. During pyrolysis of individual MSW components at 500°C, the wood required the least amount of heat at 665.2J/g, compared to 2483.2J/g for textile, 2059.4J/g for paper and 2256.1J/g for PET plastic. The PET plastic had much higher activation energy of 181.86kJ/mol, compared to 41.47kJ/mol for wood, 50.01kJ/mol for paper and 36.65kJ/mol for textile during pyrolysis at a heating rate of 10°C/min. H2O and H2 peaks were observed on the MS curves for the pyrolysis of three biomass-derived materials but there was no obvious H2O and H2 peaks on the MS curves of PET plastic. There was a significant interaction between biomass and PET plastic during co-pyrolysis if the biomass fraction was dominant. The amount of heat required for the co-pyrolysis of the biomass and plastic mixture increased with the increase of plastic mass fraction in the mixture. Torrefaction at a proper temperature and time could improve the grindability of PET plastic. The increase of torrefaction temperature and time did not affect the temperature where the maximum pyrolytic rates occurred for both biomass and plastic but decreased the maximum pyrolysis rate of biomass and increased the maximum pyrolysis

  5. Calorimetric study of Te15(Se100- x Bi x )85 glassy alloys using differential thermal analysis

    NASA Astrophysics Data System (ADS)

    Kumar, Kameshwar; Thakur, Nagesh; Bhatt, S. S.; Sharma, Pankaj

    2010-10-01

    A calorimetric study of Te15(Se100- x Bi x )85 glassy alloys (x = 0, 1, 2, 3 and 4 at. %) is reported. Differential thermal analysis (DTA) was performed at heating rates of 10, 15, 20 and 25 K/min. The spectra were used to determine the glass transition temperature, Tg , the crystallisation temperature, Tc and the melting temperature, Tm . All these parameters shift to higher values with increasing heating rate, β. The glass transition temperature and the melting temperature increase, and the crystallisation temperature decreases, with increase in the Bi content, x. The activation energy of the glass transition, Eg , was evaluated using the Moynihan and Kissinger methods. The activation energy of crystallisation, Ec , was calculated using modified Kissinger and Matusita approaches. The thermal stability of these glasses has been studied and found to decrease with increase in Bi content. The results obtained are explained on the basis of a chemically ordered network model and an average coordination number.

  6. A micromachined calorimetric gas sensor: an application of electrodeposited nanostructured palladium for the detection of combustible gases.

    PubMed

    Bartlett, Philip N; Guerin, Samuel

    2003-01-01

    Palladium films with regular nanoarchitectures were electrochemically deposited from the hexagonal (H1) lyotropic liquid crystalline phase of the nonionic surfactant octaethyleneglycol monohexadecyl ether (C16EO8) onto micromachined silicon hotplate structures. The H1-e Pd films were shown to have high surface areas (approximately 28 m2 g(-1)) and to act as effective and stable catalysts for the detection of methane in air on heating to 500 degrees C. The response of the H1-e Pd-coated planar pellistors was found to be linearly proportional to the concentration of methane between 0 and 2.5% in air with a detection limit below 0.125%. Our results show that the electrochemical deposition of nanostructured metal films offers a promising approach to the fabrication of micromachined calorimetric gas sensors for combustible gases. PMID:12530828

  7. Approche de prise en charge du trouble du spectre de l’autisme

    PubMed Central

    Lee, Patrick F.; Thomas, Roger E.; Lee, Patricia A.

    2015-01-01

    Résumé Objectif Se pencher sur les critères diagnostiques du trouble du spectre de l’autisme (TSA) comme les définit le Manuel diagnostique et statistique des troubles mentaux, cinquième édition (DSM-V), et concevoir une approche de prise en charge du TSA à l’aide du cadre CanMEDS–Médecine familiale (CanMEDS-MF). Sources d’information Le DSM-V, publié par l’American Psychiatric Association en mai 2013, énonce de nouveaux critères diagnostiques du TSA. Le cadre CanMEDS-MF du Collège des médecins de famille du Canada fournit un plan d’orientation pour la prise en charge complexe du TSA. Nous avons utilisé des données recueillies par le Centers for Disease Control and Prevention afin de déterminer la prévalence du TSA, ainsi que la revue systématique et méta-analyse détaillée effectuée par le National Institute for Health and Care Excellence du R.-U. pour ses lignes directrices sur le TSA dans le but d’évaluer les données probantes issues de plus de 100 interventions. Message principal Selon les données du Centers for Disease Control and Prevention, la prévalence du TSA se chiffrait à 1 sur 88 en 2008 aux États-Unis. La classification du TSA dans la quatrième édition du DSM incluait l’autisme, le syndrome d’Asperger, le trouble envahissant du développement et le trouble désintégratif de l’enfance. La dernière révision du DSM-V réunit tous ces troubles sous la mention TSA, avec différents niveaux de sévérité. La prise en charge du TSA est complexe; elle exige les efforts d’une équipe multidisciplinaire ainsi que des soins continus. Les rôles CanMEDS-MF fournissent un cadre de prise en charge. Conclusion Les médecins de famille sont au cœur de l’équipe de soins multidisciplinaire pour le TSA, et le cadre CanMEDS-MF tient lieu de plan détaillé pour guider la prise en charge d’un enfant atteint de TSA et aider la famille de cet enfant.

  8. A Calorimetric Study of Almandine: Are the Thermodynamic Properties of the End-Member Aluminosilicate Garnets Finally Known Quantitatively?

    NASA Astrophysics Data System (ADS)

    Dachs, E.; Geiger, C. A.; Benisek, A.

    2012-12-01

    The aluminosilicate garnets (E3Al2Si3O12 with E = Fe2+, Mn2+, Ca, Mg) form an important rock-forming mineral group. Much study has been directed toward determining their thermodynamic properties. The iron end-member almandine (Fe3Al2Si3O12) is a key phase in many petrologic investigations. As part of an ongoing calorimetric and thermodynamic study of the aluminosilicate garnets, the heat capacity of three synthetic well-characterized polycrystalline almandine garnets and one natural almandine-rich single crystal was measured. The various garnets were characterized by optical microscopy, electron-microprobe analysis, X-ray powder diffraction and 57Fe Mössbauer spectroscopy. Heat capacity measurements were performed in the temperature range 3 to 300 K using relaxation calorimetry and between 282 and 764 K using DSC methods. From the former, So values between 336.7 ± 0.8 and 337.8 ± 0.8 J/molK are calculated for the different samples. The smaller value is considered the best So for end-member stoichiometric almandine, because it derives from the "best" Fe3+-free synthetic sample. The Cp behavior for almandine at T > 298 K is given by the polynomial (in J/molK): Cp = 649.06(±4) - 3837.57(±122)T-0.5 - 1.44682(±0.06)107T-2 + 1.94834(±0.09)109T-3, which is calculated using DSC data together with one published heat-content datum determined by transposed-drop calorimetry along with a new determination that gives H1181K - H302K = 415.0 ± 3.2 kJ/mole. Almandine shows a λ-type heat-capacity anomaly at low temperatures resulting from a paramagnetic-antiferromagnetic phase transition at about 9 K. The lattice heat capacity was calculated using the single-parameter phonon dispersion model of Komada and Westrum (1997), which allows the non-lattice heat capacity (Cex) behavior to be modelled. An analysis shows the presence of an electronic heat-capacity contribution (Cel - Schottky anomaly) around 17 K that is superimposed on a larger magnetic heat-capacity effect (Cmag

  9. Les plaies du tendon patellaire

    PubMed Central

    Mechchat, Atif; Elidrissi, Mohammed; Mardy, Abdelhak; Elayoubi, Abdelghni; Shimi, Mohammed; Elibrahimi, Abdelhalim; Elmrini, Abdelmajid

    2014-01-01

    Les plaies du tendon patellaire sont peu fréquentes et sont peu rapportés dans la littérature, contrairement aux ruptures sous cutanées. Les sections du tendon patellaire nécessitent une réparation immédiate afin de rétablir l'appareil extenseur et de permettre une récupération fonctionnelle précoce. A travers ce travail rétrospectif sur 13 cas, nous analysons les aspects épidémiologiques, thérapeutiques et pronostiques de ce type de pathologie en comparant différents scores. L’âge moyen est de 25 ans avec une prédominance masculine. Les étiologies sont dominées par les accidents de la voie publique (68%) et les agressions par agent tranchant (26%) et contendant (6 %). Tous nos patients ont bénéficié d'un parage chirurgical avec suture tendineuse direct protégée par un laçage au fils d'aciers en légère flexion. La rééducation est débutée après sédation des phénomènes inflammatoires. Au dernier recul les résultats sont excellents et bon à 92%. Nous n'avons pas noté de différence de force musculaire et d'amplitude articulaire entre le genou sain et le genou lésé. Les lésions ouvertes du tendon patellaire est relativement rare. La prise en charge chirurgicale rapide donne des résultats assez satisfaisants. La réparation est généralement renforcée par un semi-tendineux, synthétique ou métallique en forme de cadre de renfort pour faciliter la réadaptation et réduire le risque de récidive après la fin de l'immobilisation. PMID:25170379

  10. Learning about Cri du Chat Syndrome

    MedlinePlus

    ... chat syndrome - also known as 5p- syndrome and cat cry syndrome - is a rare genetic condition that ... du chat syndrome usually include a high-pitched cat-like cry, mental retardation, delayed development, distinctive facial ...

  11. Design and performance tests of the calorimetric tract of a Compton Camera for small-animals imaging

    NASA Astrophysics Data System (ADS)

    Rossi, P.; Baldazzi, G.; Battistella, A.; Bello, M.; Bollini, D.; Bonvicini, V.; Fontana, C. L.; Gennaro, G.; Moschini, G.; Navarria, F.; Rashevsky, A.; Uzunov, N.; Zampa, G.; Zampa, N.; Vacchi, A.

    2011-02-01

    The bio-distribution and targeting capability of pharmaceuticals may be assessed in small animals by imaging gamma-rays emitted from radio-isotope markers. Detectors that exploit the Compton concept allow higher gamma-ray efficiency compared to conventional Anger cameras employing collimators, and feature sub-millimeter spatial resolution and compact geometry. We are developing a Compton Camera that has to address several requirements: the high rates typical of the Compton concept; detection of gamma-rays of different energies that may range from 140 keV ( 99 mTc) to 511 keV ( β+ emitters); presence of gamma and beta radiation with energies up to 2 MeV in case of 188Re. The camera consists of a thin position-sensitive Tracker that scatters the gamma ray, and a second position-sensitive detection system to totally absorb the energy of the scattered photons (Calorimeter). In this paper we present the design and discuss the realization of the calorimetric tract, including the choice of scintillator crystal, pixel size, and detector geometry. Simulations of the gamma-ray trajectories from source to detectors have helped to assess the accuracy of the system and decide on camera design. Crystals of different materials, such as LaBr 3 GSO and YAP, and of different size, in continuous or segmented geometry, have been optically coupled to a multi-anode Hamamatsu H8500 detector, allowing measurements of spatial resolution and efficiency.

  12. Calorimetric study of the superconducting and normal state properties of Ca(Fe1-xCox)2As2

    NASA Astrophysics Data System (ADS)

    Abdel-Hafiez, M.; Harnagea, L.; Singh, S.; Stockert, U.; Wurmehl, S.; Leps, N.; Klingeler, R.; Wolter, A. U. B.; Büchner, B.

    2012-12-01

    We present a calorimetric study on single crystals of Ca(Fe1-xCox)2As2 (x = 0, 0.032, 0.051, 0.056, 0.063, and 0.146). The combined first order spin-density wave/structural transition occurs in the parent CaFe2As2 compound at 168 K and gradually shifts to lower temperature for low doping levels (x = 0.032 and x = 0.051). It is completely suppressed upon higher doping x >= 0.056. Simultaneously, superconductivity appears at lower temperature with a transition temperature around Tc ~ 14.1 K for Ca(Fe0.937Co0.063)2As2. The phase diagram of Ca(Fe0.937Co0.063)2As2 has been derived and the upper critical field is found to be μ0H(c)2 = 11.5 T and μ0H(ab)c2 = 19.4 T for the c and ab directions, respectively.

  13. Kinetic and calorimetric study of the adsorption of dyes on mesoporous activated carbon prepared from coconut coir dust.

    PubMed

    Macedo, Jeremias de Souza; da Costa Júnior, Nivan Bezerra; Almeida, Luis Eduardo; Vieira, Eunice Fragoso da Silva; Cestari, Antonio Reinaldo; Gimenez, Iara de Fátima; Villarreal Carreño, Neftali Lênin; Barreto, Ledjane Silva

    2006-06-15

    Mesoporous activated carbon has been prepared from coconut coir dust as support for adsorption of some model dye molecules from aqueous solutions. The methylene blue (MB) and remazol yellow (RY) molecules were chosen for study of the adsorption capacity of cationic and anionic dyes onto prepared activated carbon. The adsorption kinetics was studied with the Lagergren first- and pseudo-second-order kinetic models as well as the intraparticle diffusion model. The results for both dyes suggested a multimechanism sorption process. The adsorption mechanisms in the systems dyes/AC follow pseudo-second-order kinetics with a significant contribution of intraparticle diffusion. The samples simultaneously present acidic and basic sites able to act as anchoring sites for basic and acidic dyes, respectively. Calorimetric studies reveal that dyes/AC interaction forces are correlated with the pH of the solution, which can be related to the charge distribution on the AC surface. These AC samples also exhibited very short equilibrium times for the adsorption of both dyes, which is an economically favorable requisite for the activated carbon described in this work, in addition to the local abundance of the raw material. PMID:16497318

  14. Spectroscopic and calorimetric investigations on the binding of phenazinium dyes safranine-O and phenosafranine to double stranded RNA polynucleotides.

    PubMed

    Saha, Baishakhi; Kumar, Gopinatha Suresh

    2016-08-01

    RNA targeting through small molecules that can selectively bind specific RNA structures is an important current strategy in therapeutic drug development. Towards this strategy a comparative study on the interaction of two phenazinium dyes, safranine-O and phenosafranine to double stranded RNAs, poly(I).poly(C), poly(A).poly(U) and poly(C).poly(G) was performed. Spectrophotometric and spectrofluorimetric studies revealed non-cooperative binding of the dyes to the duplex RNA with binding constants of the order 10(5)M(-1) with a higher affinity of safranine-O to poly(I).poly(C) followed by poly(A).poly(U) and poly(C).poly(G). Anisotropy and fluorescence quenching results confirmed an intercalation mode of binding for the dyes on these RNAs. Binding induced conformational changes in the RNA polynucleotides were revealed from circular dichroism data. Thermal melting study and DSC experiments demonstrated stabilization of dye-RNA complexes. Calorimetric studies revealed that the binding was accompanied by a large positive entropy term with a small negative enthalpy contributions. Significant hydrophobic forces in the complexation of the double stranded RNAs with the dyes were confirmed from the negative heat capacity changes. Enthalpy-entropy compensation was also observed in the binding. Parsing of the Gibbs energy suggested a larger non-electrostatic contribution in all the cases. The results presented here may be helpful to design new types of RNA-based therapeutic agents. PMID:27236048

  15. Calorimetric AC loss measurement of MgB2 superconducting tape in an alternating transport current and direct magnetic field

    NASA Astrophysics Data System (ADS)

    See, K. W.; Xu, X.; Horvat, J.; Cook, C. D.; Dou, S. X.

    2012-11-01

    Applications of MgB2 superconductors in electrical engineering have been widely reported, and various studies have been made to define their alternating current (AC) losses. However, studies on the transport losses with an applied transverse DC magnetic field have not been conducted, even though this is one of the favored conditions in applications of practical MgB2 tapes. Methods and techniques used to characterize and measure these losses have so far been grouped into ‘electrical’ and ‘calorimetric’ approaches with external conditions set to resemble the application conditions. In this paper, we present a new approach to mounting the sample and employ the calorimetric method to accurately determine the losses in the concurrent application of AC transport current and DC magnetic fields that are likely to be experienced in practical devices such as generators and motors. This technique provides great simplification compared to the pickup coil and lock-in amplifier methods and is applied to a long length (˜10 cm) superconducting tape. The AC loss data at 20 and 30 K will be presented in an applied transport current of 50 Hz under external DC magnetic fields. The results are found to be higher than the theoretical predictions because of the metallic fraction of the tape that contributes quite significantly to the total losses. The data, however, will allow minimization of losses in practical MgB2 coils and will be used in the verification of numerical coil models.

  16. Determination of Nuclear Charge Distributions of Fission Fragments from ^{235}U (n_th, f) with Calorimetric Low Temperature Detectors

    NASA Astrophysics Data System (ADS)

    Grabitz, P.; Andrianov, V.; Bishop, S.; Blanc, A.; Dubey, S.; Echler, A.; Egelhof, P.; Faust, H.; Gönnenwein, F.; Gomez-Guzman, J. M.; Köster, U.; Kraft-Bermuth, S.; Mutterer, M.; Scholz, P.; Stolte, S.

    2016-08-01

    Calorimetric low temperature detectors (CLTD's) for heavy-ion detection have been combined with the LOHENGRIN recoil separator at the ILL Grenoble for the determination of nuclear charge distributions of fission fragments produced by thermal neutron-induced fission of ^{235}U. The LOHENGRIN spectrometer separates fission fragments according to their mass-to-ionic-charge ratio and their kinetic energy, but has no selectivity with respect to nuclear charges Z. For the separation of the nuclear charges, one can exploit the nuclear charge-dependent energy loss of the fragments passing through an energy degrader foil (absorber method). This separation requires detector systems with high energy resolution and negligible pulse height defect, as well as degrader foils which are optimized with respect to thickness, homogeneity, and energy loss straggling. In the present, contribution results of test measurements at the Maier Leibnitz tandem accelerator facility in Munich with ^{109}Ag and ^{127}I beams with the aim to determine the most suitable degrader material, as well as measurements at the Institut Laue-Langevin will be presented. These include a systematic study of the quality of Z-separation of fission fragments in the mass range 82le A le 132 and a systematic measurement of ^{92}Rb fission yields, as well as investigations of fission yields toward the symmetry region.

  17. Refractive-index-based calorimetric studies of RNAse T1 unfolding in small volumes using microinterferometric backscatter

    NASA Astrophysics Data System (ADS)

    Houlne, Michael P.; Hubbard, Darren S.; Makhatadze, George I.; Bornhop, Darryl J.

    1997-05-01

    Micro-interferometry, a novel technique developed by the authors, employs a linearly polarized laser, a fused silica capillary tube housing for the sample and a charged coupled device as a detector. A back scattered interference pattern, observed as a high contrast fringes, is produced when the laser is directed onto the capillary containing the sample. The positional change of the fringe pattern is a function of the refractive index of the media in the capillary. In the present work, the RNA enzyme RNase T1 is heated in the sample cell over a temperature range of 30 degrees C to 60 degrees C. Over this temperature range the molecule unfolds form the quaternary to the tertiary structure. This structure change is manifested as a refractive index change and is observed by monitoring the fringe position while ramping the cell temperature in a controlled fashion. From the refractive index response over the temperature range, the Gibbs free energy associated with unfolding is calculated. The authors show milli-degree temperature stability with a 0.1 micro-liter probe volume, thus demonstrating the application of this device in micro- calorimetric investigations.

  18. Calorimetric Low-Temperature Detectors for X-Ray Spectroscopy on Trapped Highly-Charged Heavy Ions

    NASA Technical Reports Server (NTRS)

    Kilbourne, Caroline; Kraft-Bermuth, S.; Andrianov, V.; Bleile, A.; Echler, A.; Egelhof, P.; Ilieva, S.; Kilbourne, C.; McCammon, D.

    2012-01-01

    The application of Calorimetric Low-Temperature Detectors (CLTDs) has been proposed at the Heavy-Ion TRAP facility HITRAP which is currently being installed at the Helmholtz Research Center for Heavy Ion Research GSI. This cold ion trap setup will allow the investigation of X-rays from ions practically at rest, for which the excellent energy resolution of CLTDs can be used to its full advantage. However, the relatively low intensities at HITRAP demand larger solid angles and an optimized cryogenic setup. The influence of external magnetic fields has to be taken into account. CLTDs will also be a substantial part of the instrumental equipment at the future Facility for Antiproton and Heavy Ion Research (FAIR), for which a wide variety of high-precision X-ray spectroscopy experiments has been proposed. This contribution will give an overview on the chances and challenges for the application of CLTDs at HITRAP as well as perspectives for future experiments at the FAIR facility.

  19. Surfactants induced release of a red emitting dye from the nanocavity of a molecular container: A spectroscopic and calorimetric study.

    PubMed

    Ahmed, Sayeed Ashique; Chatterjee, Aninda; Maity, Banibrata; Seth, Debabrata

    2016-08-01

    Supramolecular interaction of a red emitting dye Nile blue A (NBA) with Cucurbit[7]uril (CB7) in aqueous solution was studied and the release of the dye from the hydrophobic cavity of CB7 was reported. To investigate the supramolecular host-guest complex formation and release of dye, we have used the steady state absorption, fluorescence and time resolved fluorescence emission spectroscopy, (1)H NMR spectroscopy and isothermal titration calorimetry (ITC). The spectral properties of NBA were changed in the presence of CB7. The change in spectral features of NBA in presence of CB7 indicates the formation of supramolecular host-guest complexes. By using the SED equation the diameter of the complex was estimated. The complex formation further affirmed by the (1)H NMR study. Upfield and downfield shifts of the protons of NBA was observed in both the aliphatic and aromatic region. From the ITC measurement, we have drawn up the forces involved for the complexation of NBA with CB7. We have studied the release of NBA from the hydrophobic cavity of CB7 by using ionic, neutral surfactants and ionic liquid with the help of spectroscopic and calorimetric techniques. It is observed that on addition of SDS and ionic liquid (

  20. Determination of Nuclear Charge Distributions of Fission Fragments from ^{235} U (n_th , f) with Calorimetric Low Temperature Detectors

    NASA Astrophysics Data System (ADS)

    Grabitz, P.; Andrianov, V.; Bishop, S.; Blanc, A.; Dubey, S.; Echler, A.; Egelhof, P.; Faust, H.; Gönnenwein, F.; Gomez-Guzman, J. M.; Köster, U.; Kraft-Bermuth, S.; Mutterer, M.; Scholz, P.; Stolte, S.

    2016-03-01

    Calorimetric low temperature detectors (CLTD's) for heavy-ion detection have been combined with the LOHENGRIN recoil separator at the ILL Grenoble for the determination of nuclear charge distributions of fission fragments produced by thermal neutron-induced fission of ^{235} U. The LOHENGRIN spectrometer separates fission fragments according to their mass-to-ionic-charge ratio and their kinetic energy, but has no selectivity with respect to nuclear charges Z. For the separation of the nuclear charges, one can exploit the nuclear charge-dependent energy loss of the fragments passing through an energy degrader foil (absorber method). This separation requires detector systems with high energy resolution and negligible pulse height defect, as well as degrader foils which are optimized with respect to thickness, homogeneity, and energy loss straggling. In the present, contribution results of test measurements at the Maier Leibnitz tandem accelerator facility in Munich with ^{109} Ag and ^{127} I beams with the aim to determine the most suitable degrader material, as well as measurements at the Institut Laue-Langevin will be presented. These include a systematic study of the quality of Z-separation of fission fragments in the mass range 82≤ A ≤ 132 and a systematic measurement of ^{92} Rb fission yields, as well as investigations of fission yields toward the symmetry region.

  1. pH-tuneable binding of 2′-phospho-ADP-ribose to ketopantoate reductase: a structural and calorimetric study

    SciTech Connect

    Ciulli, Alessio; Lobley, Carina M. C.; Tuck, Kellie L.; Smith, Alison G.; Blundell, Tom L.; Abell, Chris

    2007-02-01

    A combined crystallographic, calorimetric and mutagenic study has been used to show how changes in pH give rise to two distinct binding modes of 2′-phospho-ADP-ribose to ketopantoate reductase. The crystal structure of Escherichia coli ketopantoate reductase in complex with 2′-monophosphoadenosine 5′-diphosphoribose, a fragment of NADP{sup +} that lacks the nicotinamide ring, is reported. The ligand is bound at the enzyme active site in the opposite orientation to that observed for NADP{sup +}, with the adenine ring occupying the lipophilic nicotinamide pocket. Isothermal titration calorimetry with R31A and N98A mutants of the enzyme is used to show that the unusual ‘reversed binding mode’ observed in the crystal is triggered by changes in the protonation of binding groups at low pH. This research has important implications for fragment-based approaches to drug design, namely that the crystallization conditions and the chemical modification of ligands can have unexpected effects on the binding modes.

  2. Pru du 2S albumin or Pru du vicilin?

    PubMed

    Garino, Cristiano; De Paolis, Angelo; Coïsson, Jean Daniel; Arlorio, Marco

    2015-06-01

    A short partial sequence of 28 amino acids is all the information we have so far about the putative allergen 2S albumin from almond. The aim of this work was to analyze this information using mainly bioinformatics tools, in order to verify its rightness. Based on the results reported in the paper describing this allergen from almond, we analyzed the original data of amino acids sequencing through available software. The degree of homology of the almond 12kDa protein with any other known 2S albumin appears to be much lower than the one reported in the paper that firstly described it. In a publicly available cDNA library we discovered an expressed sequence tag which translation generates a protein that perfectly matches both of the sequencing outputs described in the same paper. A further analysis indicated that the latter protein seems to belong to the vicilin superfamily rather than to the prolamin one. The fact that also vicilins are seed storage proteins known to be highly allergenic would explain the IgE reactivity originally observed. Based on our observations we suggest that the IgE reactive 12kDa protein from almond currently known as Pru du 2S albumin is in reality the cleaved N-terminal region of a 7S vicilin like protein. PMID:25854802

  3. Biokinetics and dosimetry of depleted uranium (DU) in rats implanted with DU fragments.

    SciTech Connect

    Guilmette, Ray A.; Hahn, Fletcher F.; Durbin, P. W.

    2004-01-01

    A number of U. S. veterans of the Persian Gulf War were wounded with depleted uranium (DU) metal fragments as a result of 'friendly fire' incidents, in which Abrams tanks and Bradley fighting vehicles were struck by DU anti-armor munitions. Some of the crew members who survived were left with multiple small fragments of DU in their muscles and soft tissues. The number, size and location of the fragments made them inoperable in general, and therefore subject to long-term retention. Because there was inadequate data to predict the potential carcinogenicity of DU fragments in soft tissues, Hahn et al. (2003) conducted a lifespan cancer study in rats. As part of that study, a number of rats were maintained to study the biokinetics and dosimetry of DU implanted intramuscularly in male Wistar rats. Typically, four metal fragments, either as cylindrical pellets or square wafers were implanted into the biceps femoris muscles of the rats. Urine samples were collected periodically during their lifespans, and DU was analyzed in kidneys and eviscerated carcass (minus the implant sites) at death. The daily DU urinary excretion rate increased steeply during the first 30 d after implantation peaking at about 90 d at 3-10 x 10{sup -3}%/d. During the first 150 d, the average excretion rate was 2.4 x 10{sup -3}%/d, decreasing thereafter to about 1 x 10{sup -3}%/d. Serial radiographs were made of the wound sites to monitor gross morphologic changes in the DU implant and the surrounding tissue. As early as 1 w after implantation, radiographs showed the presence of surface corrosion and small, dense bodies near the original implant, presumably DU. This corrosion from the surface of the implant continued with time, but did not result in an increasing amount of DU reaching the blood and urine after the first 3 mo. During this 3-mo period, connective tissue capsules formed around the implants, and are hypothesized to have reduced the access of DU to tissue fluids by limiting the diffusion

  4. Résultats du traitement du synovialosarcome des members

    PubMed Central

    Lukulunga, Loubet Unyendje; Moussa, Abdou Kadri; Mahfoud, Mustapha; El Bardouni, Ahmed; Ismail, Farid; Kharmaz, Mohammed; Berrada, Mohamed Saleh; El Yaacoubi, Moradh

    2014-01-01

    Les synovialosarcomes, sarcomes de haut grade, sont de diagnostic tardif et le traitement est complexe et onéreux, nécessitant la mise en œuvre d'une équipe pluridisciplinaire. Le but de ce travail était d'apprécier les résultats de l'association de la chirurgie à la radio chimiothérapie des synovialosarcomes des membres. Il s'agissait d'une étude rétrospective portant sur des patients présentant de synovialosarcomes des membres pris en charge dans le service de chirurgie orthopédique et traumatologique du CHU Ibn SINA de Rabat allant de Janvier 2006 à Décembre 2011 (6 ans). Nous avons inclus les malades présentant de synovialosarcomes des membres dont la clinique et l'imagerie médicale étaient en faveur, confirmés par l'examen anatomopathologique et la prise en charge effectuée dans le service. Les patients ont été revus avec un recul moyen de 3 ans. Nous n'avons pas retenu les patients dont les dossiers étaient incomplets, perdus de vue. Nous avons apprécié les résultats selon les critères carcinologiques et le score MSTS (Musculoskeletal Tumor Society). La saisie et l'analyse des données ont été faites sur le logiciel SPSS Stastic 17.0 Nous avons colligé 20 cas de synovialosarcome des membres dans le Service de Chirurgie Orthopédique et Traumatologique au CHU Ibn SINA de Rabat Le sexe masculin a prédominé avec 65% (n = 13) avec un sex ratio 1,85. L’âge moyen a été de 42,6 ans avec des extrêmes allant de 20 ans et 70 ans. Notre délai moyen de consultation était de 14,42 mois. Tous les malades ont consulté pour une tuméfaction dans 100% (localisée au membre inférieur dans 65% (n = 13), membre supérieur dans 35% (n = 7). La douleur était associée à la tuméfaction dans 55% (n = 11), quant à l'altération de l’état général et l'ulcération de la masse, elles ont été notées dans 3 cas chacune. Nous avons réalisé un bilan d'imagerie médicale comprenant: radiographie standard, échographie, écho doppler

  5. Calorimetric investigation of triazole-bridged Fe(II) spin-crossover one-dimensional materials: measuring the cooperativity.

    PubMed

    Roubeau, Olivier; Castro, Miguel; Burriel, Ramón; Haasnoot, Jaap G; Reedijk, Jan

    2011-03-31

    The relevance of abrupt magnetic and optical transitions exhibiting bistability in spin-crossover solids has been pointed out for their potential applications in optical or memory devices. In this respect, triazole-based one-dimensional coordination polymers are widely recognized as one of the most interesting systems. The measure of the interaction among spin-crossover centers at the origin of such cooperative behavior is of paramount importance and has so far been realized through modeling of spin-crossover curves derived mostly from magnetic measurements. Here, a new series of triazole-based one-dimensional coordination polymers of formula [Fe(Rtrz)(3)](A)(2)·xH(2)O with R = methoxyethyl and A = monovalent anion has been prepared that show complete and abrupt spin-crossover phenomenon as shown by magnetic measurements. The spin-crossover transition in these and related compounds is studied by differential scanning calorimetry, and the thermodynamic excess enthalpies and entropies associated with the phenomenon are derived systematically. Then the cooperative character of the spin-crossover in these materials is quantified by use of two widely used models, so-called Slichter and Drickamer and domain models. The same procedure is applied to spin-crossover curves of similar compounds available in the literature and for which calorimetric studies have been reported. The experimental thermodynamic figures, in particular the excess enthalpies, are shown to be clearly correlated to the output parameters of both models, thus providing a direct, experimental, quantitative measure of the cooperative character of the spin-crossover phenomenon. PMID:21381636

  6. Thermogravimetric, Calorimetric, and Structural Studies of the Co3 O4 /CoO Oxidation/Reduction Reaction

    NASA Astrophysics Data System (ADS)

    Unruh, Karl; Cichocki, Ronald; Kelly, Brian; Poirier, Gerald

    2015-03-01

    To better assess the potential of cobalt oxide for thermal energy storage (TES), the Co3O4/CoO oxidation/reduction reaction has been studied by thermogravimetric (TGA), calorimetric (DSC), and x-ray diffraction (XRD) measurements in N2 and atmospheric air environments. TGA measurements showed an abrupt mass loss of about 6.6% in both N2 and air, consistent with the stoichiometric reduction of Co3O4 to CoO and structural measurements. The onset temperature of the reduction of Co3O4 in air was only weakly dependent on the sample heating rate and occurred at about 910 °C. The onset temperature for the oxidation of CoO varied between about 850 and 875 °C for cooling rates between 1 and 20 °C/min, but complete re-conversion to Co3O4 could only be achieved at the slowest cooling rates. Due to the dependence of the rate constant on the oxygen partial pressure, the oxidation of Co3O4 in a N2 environment occurred at temperatures between about 775 and 825 °C for heating rates between 1 and 20 °C/min and no subsequent re-oxidation of the reduced Co3O4 was observed on cooling to room temperature. In conjunction with a measured transition heat of about 600 J/g of Co3O4, these measurements indicate that cobalt oxide is a viable TES material.

  7. Spectroscopic and calorimetric studies on the binding of an indoloquinoline drug to parallel and antiparallel DNA triplexes.

    PubMed

    Riechert-Krause, Fanny; Autenrieth, Karolin; Eick, Andrea; Weisz, Klaus

    2013-01-01

    11-Phenyl-substituted indoloquinolines have been found to exhibit significant antiproliferative potency in cancer cells but to show only moderate affinity toward genomic double-helical DNA. In this study, parallel as well as antiparallel triple-helical DNA targets are employed to evaluate the triplex binding of these ligands. UV melting experiments with parallel triplexes indicate considerable interactions with the drug and a strong preference for TAT-rich triplexes in line with an increasing number of potential intercalation sites of similar binding strength between two TAT base triads. Via substitution of a singly charged aminoethylamine side chain by a longer and doubly charged bis(aminopropyl)amine substituent at the ligand, binding affinities increase and also start to exhibit long-range effects as indicated by a strong correlation between the binding affinity and the overall length of the TAT tract within the triplex stem. Compared to parallel triplexes, an antiparallel triplex with a GT-containing third strand constitutes a preferred target for the indoloquinoline drug. On the basis of pH-dependent titration experiments and corroborated by a Job analysis of continuous variation, binding of the drug to the GT triplex not only is strongly enhanced when the solution pH is lowered from 7 to 5 but also reveals a pH-dependent stoichiometry upon formation of the complex. Calorimetric data demonstrate that stronger binding of a protonated drug at acidic pH is associated with a more exothermic binding process. However, at pH 7 and 5, binding is enthalpically driven with additional favorable entropic contributions. PMID:23234257

  8. Calorimetric and spectroscopic studies on solvation energetics for H2 storage in the CO2/HCOOH system.

    PubMed

    Fink, Cornel; Katsyuba, Sergey; Laurenczy, Gabor

    2016-04-20

    Solvents playing a crucial role in many chemical reactions and additives can be used to shift the reaction equilibrium. Herein we study the enthalpy of mixing for selected solvents (aqueous, organic) and basic additives (amines, aqueous KOH) when mixed with formic acid with the aim to optimize hydrogen storage/delivery in the CO2/HCOOH system. Formic acid, resulting from carbon dioxide hydrogenation, reaches highest yields when effectively "removed" from the reaction equilibrium. In terms of energy efficiency, any heat released during CO2 hydrogenation has to be reused in the reverse reaction, during the production of hydrogen. In any scenario, the usage of basic chemicals, non-innocent solvents, causes higher energy release in CO2 hydrogenation, which has to be reused in the hydrogen delivery process. Therefore, the enthalpy of mixing is a valuable parameter for designing hydrogen storage devices since it allows the estimation of energy balance for the CO2 hydrogenation/H2 liberation cycle. The highest formic acid concentrations in direct catalytic CO2 hydrogenation under acidic conditions were reached in DMSO. DMSO exhibits considerably stronger interactions with formic acid compared to water as was observed in calorimetric measurements. This difference can be ascribed, at least partly, to stronger hydrogen bonding of FA to DMSO than to water in the corresponding solutions, examined by a combination of IR spectroscopic and quantum chemical studies. Furthermore, the investigation of DMSO/FA- and water/FA systems by (1)H- and (13)C-NMR spectroscopy revealed that only 1 : 1 aggregates are formed in the DMSO solutions of FA in a broad concentration range, while the stoichiometry and the number of the FA-water aggregates essentially depend on the concentration of aqueous solutions. PMID:26890151

  9. Exploring the comparative binding aspects of benzophenanthridine plant alkaloid chelerythrine with RNA triple and double helices: a spectroscopic and calorimetric approach.

    PubMed

    Haque, Lucy; Pradhan, Ankur Bikash; Bhuiya, Sutanwi; Das, Suman

    2015-07-14

    A comparative study on the interaction of a benzophenanthridine alkaloid chelerythrine (CHL) with RNA triplex poly(U).poly(A)*poly(U) (hereafter U.A*U, .(dot) and *(asterisk) represent Watson-Crick and Hoogsteen base pairing respectively) and its parent duplex poly(A).poly(U) (A.U) was carried out by using a combination of various spectroscopic, viscometric and calorimetric techniques. The interaction was characterized by hypochromic and bathochromic effects in the absorption spectrum, the increase of thermal melting temperature, enhancement in solution viscosity, and perturbation in the circular dichroic spectrum. The binding constant calculated by using spectrophotometric data was in the order of 10(5) for both forms of RNA, but it was greater for triplex RNA (30.2 × 10(5) M(-1)) than duplex RNA (3.6 × 10(5) M(-1)). Isothermal titration calorimetric data are in good agreement with the spectrophotometric data. The data indicated stronger binding of CHL to the triplex structure of RNA compared to the native duplex structure. Thermal melting studies indicated greater stabilization of the Hoogsteen base paired third strand of the RNA triplex compared to its Watson-Crick strands. The mode of binding of CHL to both U.A*U and A.U was intercalation as revealed from fluorescence quenching, viscosity measurements and sensitization of the fluorescence experiment. Thermodynamic data obtained from isothermal calorimetric measurements revealed that association was favoured by both a negative enthalpy change and a positive entropy change. Taken together, our results suggest that chelerythrine binds and stabilizes the RNA triplex more strongly than its respective parent duplex. The results presented here may be useful for formulating effective antigene strategies involving benzophenanthridine alkaloids and the RNA triplex. PMID:26073991

  10. Calorimetric and acoustic emission study of martensitic transformation in single-crystalline Ni2MnGa alloys

    NASA Astrophysics Data System (ADS)

    Tóth, László Z.; Szabó, Sándor; Daróczi, Lajos; Beke, Dezső L.

    2014-12-01

    The jerky character of austenite-martensite phase transformation in Ni2MnGa single crystals (with 10M martensite structure) has been investigated by thermal cycling using a differential scanning calorimeter (DSC) and by detection of acoustic emissions (AEs) at low cooling and heating rates (0.1 K/min and below). It is illustrated that, besides the low cooling and heating rate, mass and surface roughness are also important parameters in optimizing the best signal/noise ratio in order to obtain individual peaks suitable for statistical analysis. Three types of samples, differing in the twin structure and twin boundary behavior, were investigated with and without surface roughening made by electro-erosion. The statistical analysis, carried out for both (thermal and acoustic) types of signals, provided power-law behavior. In calorimetric measurements the energy exponents, obtained in cooling, were the same within the experimental errors (ɛ =1.7 ±0.2 ) for the three samples investigated. In acoustic emission experiments the energy and amplitude, α , exponents were determined both for cooling and heating. The exponents for cooling and heating runs are slightly different. They are larger for heating for both α and ɛ , in accordance with the asymmetric acoustic activity: we observed higher acoustic activity (higher number of hits) during cooling. The effect of the surface roughness is negligible in the exponents (but higher acoustic activity corresponds to higher roughness) and the following values were obtained: ɛ =1.5 ±0.1 and α =2.1 ±0.1 for cooling as well as ɛ =1.8 ±0.1 and α =2.6 ±0.1 for heating. Our results are in accordance with the results of Gallardo et al. [Phys. Rev. B 81, 174102 (2010), 10.1103/PhysRevB.81.174102] obtained in Cu based alloys: the exponents of the energy distributions, for both DSC and AE signals, were the same within the experimental errors. Furthermore, our exponents obtained from the AE measurements are close to the values

  11. Trophic relay and prey switching - A stomach contents and calorimetric investigation of an ambassid fish and their saltmarsh prey

    NASA Astrophysics Data System (ADS)

    McPhee, Jack J.; Platell, Margaret E.; Schreider, Maria J.

    2015-12-01

    Trophic relay is an ecological model that involves the movement of biomass and energy from vegetation, such as saltmarshes, within estuaries to the open sea via a series of predator-prey relationships. Any potential for trophic relay is therefore affected by water movements within an estuary and by the ability of a predator to "switch" prey in response to fluctuating abundances of those prey. Saltmarsh-dwelling grapsid crabs, which feed on saltmarsh-derived detritus and microphytobenthos, release zoeae into ebbing tides that inundate saltmarshes during spring-tide cycles within tidally-dominated estuaries, such as Brisbane Water Estuary, therefore providing an opportunity to examine whether prey-switching and/or trophic relay may occur in fish that feed on those zoeae (such as the highly abundant estuarine ambassid, Ambassis jacksoniensis). This model was examined by sampling A. jacksoniensis near saltmarshes in a large, temperate south-eastern Australian estuary during flood and ebb tides on days of saltmarsh inundation and non-inundation over four spring-tide events in 2012. Stomach fullnesses of A. jacksoniensis were generally highest during ebb tides on days of saltmarsh inundation, implying that feeding was most marked at these times. Caridean decapods dominated diets during flood tides and on days of no saltmarsh inundation, while crab zoeae dominated diets during ebb tides and on days of inundation, suggesting that, when saltmarsh-derived zoeae became abundant, A. jacksoniensis switched to feeding on those prey. Three potential zooplankton prey (calanoid copepods, caridean decapods and crab zoeae) did not differ calorimetrically, indicating that switching of prey by A. jacksoniensis is not directly related to their preying on energetically greater prey, but reflects opportunistic feeding on more abundant and/or less elusive prey. As A. jacksoniensis is able to switch prey from estuarine caridean decapods to saltmarsh-derived crab zoeae, this very abundant

  12. Sign Communication in Cri du Chat Syndrome

    ERIC Educational Resources Information Center

    Erlenkamp, Sonja; Kristoffersen, Kristian Emil

    2010-01-01

    This paper presents findings from a study on the use of sign supported Norwegian (SSN) in two individuals with Cri du chat syndrome (CCS). The study gives a first account of some selected aspects of production and intelligibility of SSN in CCS. Possible deviance in manual parameters, in particular inter- and/or intra-subject variation in the use…

  13. Prejudice: From Allport to DuBois.

    ERIC Educational Resources Information Center

    Gaines, Stanley O., Jr.; Reed, Edward S.

    1995-01-01

    Examines the differences between Gordon Allport's and W. E. B. DuBois's theories on the origins of prejudice and the impact of discrimination on the personality and social development of blacks. The article argues that prejudice is a historically developed process, not a universal feature of human psychology. Implications for U.S. race relations…

  14. Calorimetric system and method

    DOEpatents

    Gschneidner, K.A. Jr.; Pecharsky, V.K.; Moorman, J.O.

    1998-09-15

    Apparatus is described for measuring heat capacity of a sample where a series of measurements are taken in succession comprises a sample holder in which a sample to be measured is disposed, a temperature sensor and sample heater for providing a heat pulse thermally connected to the sample, and an adiabatic heat shield in which the sample holder is positioned and including an electrical heater. An electrical power supply device provides an electrical power output to the sample heater to generate a heat pulse. The electrical power from a power source to the heat shield heater is adjusted by a control device, if necessary, from one measurement to the next in response to a sample temperature-versus-time change determined before and after a previous heat pulse to provide a subsequent sample temperature-versus-time change that is substantially linear before and after the subsequent heat pulse. A temperature sensor is used and operable over a range of temperatures ranging from approximately 3K to 350K depending upon the refrigerant used. The sample optionally can be subjected to dc magnetic fields such as from 0 to 12 Tesla (0 to 120 kOe). 18 figs.

  15. Calorimetric system and method

    DOEpatents

    Gschneidner, Jr., Karl A.; Pecharsky, Vitalij K.; Moorman, Jack O.

    1998-09-15

    Apparatus for measuring heat capacity of a sample where a series of measurements are taken in succession comprises a sample holder in which a sample to be measured is disposed, a temperature sensor and sample heater for providing a heat pulse thermally connected to the sample, and an adiabatic heat shield in which the sample holder is positioned and including an electrical heater. An electrical power supply device provides an electrical power output to the sample heater to generate a heat pulse. The electrical power from a power source to the heat shield heater is adjusted by a control device, if necessary, from one measurement to the next in response to a sample temperature-versus-time change determined before and after a previous heat pulse to provide a subsequent sample temperature-versus-time change that is substantially linear before and after the subsequent heat pulse. A temperature sensor is used and operable over a range of temperatures ranging from approximately 3K to 350K depending upon the refrigerant used. The sample optionally can be subjected to dc magnetic fields such as from 0 to 12 Tesla (0 to 120 kOe).

  16. Micromechanical calorimetric sensor

    DOEpatents

    Thundat, Thomas G.; Doktycz, Mitchel J.

    2000-01-01

    A calorimeter sensor apparatus is developed utilizing microcantilevered spring elements for detecting thermal changes within a sample containing biomolecules which undergo chemical and biochemical reactions. The spring element includes a bimaterial layer of chemicals on a coated region on at least one surface of the microcantilever. The chemicals generate a differential thermal stress across the surface upon reaction of the chemicals with an analyte or biomolecules within the sample due to the heat of chemical reactions in the sample placed on the coated region. The thermal stress across the spring element surface creates mechanical bending of the microcantilever. The spring element has a low thermal mass to allow detection and measuring of heat transfers associated with chemical and biochemical reactions within a sample placed on or near the coated region. A second surface may have a different material, or the second surface and body of microcantilever may be of an inert composition. The differential thermal stress between the surfaces of the microcantilever create bending of the cantilever. Deflections of the cantilever are detected by a variety of detection techniques. The microcantilever may be approximately 1 to 200 .mu.m long, approximately 1 to 50 .mu.m wide, and approximately 0.3 to 3.0 .mu.m thick. A sensitivity for detection of deflections is in the range of 0.01 nanometers. The microcantilever is extremely sensitive to thermal changes in samples as small as 30 microliters.

  17. Calorimetric Study of Phase Stability and Phase Transformation in U- xZr ( x = 2, 5, 10 wt pct) Alloys

    NASA Astrophysics Data System (ADS)

    Rai, Arun Kumar; Subramanian, Raju; Hajra, Raj Narayan; Tripathy, Haraprasanna; Rengachari, Mythili; Saibaba, Saroja

    2015-11-01

    A comprehensive calorimetric study of high-temperature phase equilibria and phase transformation characteristics in U- xZr ( x = 2, 5, 10 wt pct) alloys has been undertaken, as a function of heating and cooling rates. It is found that the following sequence of phase transformation takes place upon slow heating in annealed U-2 wt pct Zr alloy: α + α' + δ-UZr2 → α + γ 2 → β + γ 2 → β + γ 1 → γ. For alloys of 5 and 10 wt pct Zr, the additional presence of a miscibility gap ( γ 1 U-rich bcc + γ 2 Zr-rich bcc) in the high-temperature γ(bcc) phase region resulted in the following transformation sequence: α + α' + δ-UZr2 → α + γ 2 → β + γ 2 → γ 1 + γ 2 → γ. Further, it has been demonstrated that depending on the nature of starting microstructure, namely whether it is α eq + δ-UZr2, or a mix of α' + α eq + δ-UZr2 phases, the relative extents of two possible co-occurring modes of the first on-heating phase transformation step differ. In case of starting microstructure having mixture of three phases α' + α eq + δ-UZr2, it is found that α'-martensite relaxation via α' + α eq + δ-UZr2 → α eq + δ-UZr2 constitutes the first on-heating thermal response. The α'-martensitic relaxation is very closely followed by the dissolution of δ-UZr2. The co-occurrence of these two events gives rise to a composite thermal arrest in a normal dynamic calorimetry profile. However, if the starting microstructure is the one having the equilibrium mix of α eq and δ-UZr2, then only the peritectoidal dissolution of δ-UZr2 is found in the calorimetry profile. Unless, a very slow cooling rate of the order of 0.1 K min-1 is adopted from high-temperature γ(bcc) phase, it is not possible to obtain 100 pct of α eq phase along with equilibrium amount of δ-UZr2. At normal and high cooling rates, it is possible to suppress the diffusional decomposition of γ to varying extents. The direct γ → α'-martensite transformation has been observed at

  18. [Brief discussion on "Sanli acupoint for du-fu diseases"].

    PubMed

    Zhou, Li; He, Quan; Xin, Yu; Zhang, Hongxing

    2015-07-01

    The connotations of "du-fu" and "Sanli" in "Sanli acupoint for du-fu diseases" are discussed in this paper, which can provide theoretical foundation for the clinical application of "Sanli acupoint for du-fu diseases". Based on ancient literature combined with related theories in the Huangdi Neijing (Yellow Emperor's Canon of Internal Classic), a deep discussion is performed through the relationship between Zusanli (ST 36) and stomach, indication and mechanism of Zusanli (ST 36) on du-fu diseases and comparison between Zusanli (ST 36) and Shousanli (LI 10). It is believed that "du" should be pronounced as "dŭ", meaning stomach, and it indicates that Zusanli (ST 36) is closely related to stomach and spleen when it is used for du-fu diseases; "fu" means abdomen area, including liver-gallbladder, spleen, stomach-intestine, kidney, uterus, triple energizer; "sanli' means exclusively the acupoint of Zusanli (ST 36). PMID:26521594

  19. Du Pont Classifications of 6 Supernovae

    NASA Astrophysics Data System (ADS)

    Morrell, N.; Shappee, Benjamin J.

    2016-06-01

    We report optical spectroscopy (range 370-910 nm) of six supernovae from the Backyard Observatory Supernova Search (BOSS) and the All-Sky Automated Survey for Supernovae (ASAS-SN) using the du Pont 2.5-m telescope (+ WFCCD) at Las Campanas Observatory on June 17 2016 UT. We performed a cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J.

  20. Sustainable growth, the DuPont way.

    PubMed

    Holliday, C

    2001-09-01

    Like many manufacturers, DuPont traditionally has grown by making more and more "stuff." And its business growth has been proportional to the amount of raw materials and energy used--as well as the resulting waste and emissions from operations. Over the years, though, DuPont became aware that cheap supplies of nonrenewable resources wouldn't be endlessly available and that the earth's ecosystems couldn't indefinitely absorb the waste and emissions of production and consumption. Chad Holliday, chairman and CEO of DuPont, believes strongly in the challenge of sustainable growth and makes the business case for it: By using creativity and scientific knowledge effectively, he says, companies can provide strong returns for shareholders and grow their businesses--while also meeting the human needs of societies around the world and reducing the environmental footprint of their operations and products. In fact, a focus on sustainability can help identify new products, markets, partnerships, and intellectual property and lead to substantial business growth. Holliday describes how DuPont developed a three-pronged strategy to translate the concept of sustainability into nuts-and-bolts business practices. Focusing on integrated science, knowledge intensity, and productivity improvement, the strategy was accompanied by a new way to measure progress quantitatively. Sustainable growth should be viewed not as a program for stepped-up environmental performance but as a comprehensive way of doing business, one that delivers tremendous economic value and opens up new opportunities. Ultimately, companies will find that they can generate substantial business value through sustainability while both enhancing the quality of life around the world and protecting the environment. PMID:11550629

  1. A spectroscopic and calorimetric study of the melting behaviors of a "bent" and a "normal" DNA duplex: [d(GA4T4C)]2 versus [d(GT4A4C)]2.

    PubMed Central

    Park, Y W; Breslauer, K J

    1991-01-01

    We have calorimetrically detected and energetically characterized a premelting event in the "bent" duplex [d(GA4T4C)]2 that is absent in the "normal" duplex [d(GT4A4C)]2. This premelting may correspond to the thermally induced "unbending" of the duplex. Specifically, we have used a combination of spectroscopic and calorimetric techniques to evaluate whether differences in the electrophoretic and hydrogen exchange properties of the bent duplex, [d(GA4T4C)]2, and the normal duplex, [d(GT4A4C)]2, are paralleled by differences in the equilibrium melting properties of these duplexes. Our results reveal that the bimolecular global meltings of both duplexes exhibit two-state behavior and are characterized by the expected thermodynamic changes, as well as the expected salt-dependencies. Significantly, however, at temperatures below duplex melting and over a similar temperature range in which the aberrant electrophoretic mobility is observed (approximately less than 35 degrees C), the bent duplex exhibits calorimetric premelting behavior absent in the normal duplex. Analysis of the calorimetric data in this preglobal melting domain (approximately less than 35 degrees C) allows us to estimate a lower-limit value of 1.6 kcal/(mol-base pair) for the thermally induced unbending of the decameric duplex. PMID:1996356

  2. Cloning and sequencing of Duck circovirus (DuCV).

    PubMed

    Hattermann, K; Schmitt, C; Soike, D; Mankertz, A

    2003-12-01

    The genome of Duck circovirus (DuCV) is circular and 1996 nts in size. Two major open reading frames were identified, encoding the replicase (V1) and the capsid protein (C1). A stem-loop structure comprising the nonamer 5'-TATTATTAC, conserved in all circo-, nano- and geminiviruses, was found. Unique to DuCV, the region between the 3'-ends of the rep and cap gene contains four repeats of a 44-bp sequence. Phylogenetic analysis shows close relation of DuCV with Goose circovirus and suggests classification of DuCV as a new member of the genus Circovirus of the virus family Circoviridae. PMID:14648300

  3. Development of a new type of high pressure calorimetric cell, mechanically agitated and equipped with a dynamic pressure control system: Application to the characterization of gas hydrates

    SciTech Connect

    Plantier, F. Missima, D.; Torré, J.-P.; Marlin, L.

    2013-12-15

    A novel prototype of calorimetric cell has been developed allowing experiments under pressure with an in situ agitation system and a dynamic control of the pressure inside the cell. The use of such a system opens a wide range of potential practical applications for determining properties of complex fluids in both pressurized and agitated conditions. The technical details of this prototype and its calibration procedure are described, and an application devoted to the determination of phase equilibrium and phase change enthalpy of gas hydrates is presented. Our results, obtained with a good precision and reproducibility, were found in fairly good agreement with those found in literature, illustrate the various interests to use this novel apparatus.

  4. Calorimetric Studies of the Energetics of Order-Disorder in the System Mg(1-x)Fe(x)Ca(CO(3))(2)

    SciTech Connect

    Brady, P.; Dooley, D.; Navrotsky, A.; Reeder, R.

    1999-02-10

    Calorimetric studies by Chai and Navrotsky (1996) on dolomite-ankerite energetic have been extended by including two additional types of samples: a very disordered stoichiometric MgCa(CO{sub 3}){sub 2} prepared from low temperature aqueous solution and three largely ordered natural samples of intermediate iron content. Combining these data with previous work, three distinct trends of energetic can be seen: those for samples with nearly complete order, nearly complete disorder, and intermediate order. From these trends, the enthalpy of complete disordering is estimated to be 33 {+-} 6 kJ/mol for MgCa(CO{sub 3}){sub 2} and 18 {+-} 5 kJ/mol for FeCa(CO{sub 3}){sub 2}.

  5. Search for Low-Mass Weakly Interacting Massive Particles Using Voltage-Assisted Calorimetric Ionization Detection in the SuperCDMS Experiment

    NASA Astrophysics Data System (ADS)

    Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Bowles, M. A.; Brandt, D.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Cerdeno, D. G.; Chagani, H.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hertel, S. A.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Kiveni, M.; Koch, K.; Loer, B.; Lopez Asamar, E.; Mahapatra, R.; Mandic, V.; Martinez, C.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Moore, D. C.; Nadeau, P.; Nelson, R. H.; Page, K.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Saab, T.; Sadoulet, B.; Sander, J.; Schneck, K.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Villano, A. N.; Welliver, B.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.; SuperCDMS Collaboration

    2014-01-01

    SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of 170 eVee (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV /c2.

  6. Calorimetric determination of the magnetic phase diagram of underdoped ortho II YBa2Cu3O6.54 single crystals

    PubMed Central

    Marcenat, C.; Demuer, A.; Beauvois, K.; Michon, B.; Grockowiak, A.; Liang, R.; Hardy, W.; Bonn, D. A.; Klein, T.

    2015-01-01

    The recent discovery of a charge order in underdoped YBa2Cu3Oy raised the question of the interplay between superconductivity and this competing phase. Understanding the normal state of high-temperature superconductors is now an essential step towards the description of the pairing mechanism in those materials and determining the upper critical field is therefore of fundamental importance. We present here a calorimetric determination of the field–temperature phase diagram in underdoped YBa2Cu3Oy single crystals. We show that the specific heat saturates in high magnetic fields. This saturation is consistent with a normal state without any significant superconducting contribution and a total Sommerfeld coefficient γN∼6.5±1.5 mJ mol−1 K−2 putting strong constraints on the theoretical models for the Fermi surface reconstruction. PMID:26294047

  7. A Search for Low-Mass Weakly Interacting Massive Particles Using Voltage-Assisted Calorimetric Ionization Detection in the SuperCDMS Experiment

    SciTech Connect

    Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Bowles, M. A.; Brandt, D.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Cerdeno, D. G.; Chagani, H.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, Priscilla B.; Daal, M.; Di Stefano, P. C.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, Jeter C.; Harris, H. R.; Hertel, S. A.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Kiveni, M.; Koch, K.; Loer, B.; Lopez Asamar, E.; Mahapatra, R.; Mandic, V.; Martinez, C.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Moore, D. C.; Nadeau, P.; Nelson, R. H.; Page, K.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redi, P.; Reisetter, A.; Ricci, Y.; Saab, T.; Sadoulet, B.; Sander, J.; Schneck, K.; Schnee, Richard; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Villano, A. N.; Welliver, B.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2014-01-27

    SuperCDMS is an experiment designed to directly detect weakly interacting massive particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this Letter, we present WIMP-search results using a calorimetric technique we call CDMSlite, which relies on voltage-assisted Luke-Neganov amplification of the ionization energy deposited by particle interactions. The data were collected with a single 0.6 kg germanium detector running for ten live days at the Soudan Underground Laboratory. A low energy threshold of (electron equivalent) was obtained, which allows us to constrain new WIMP-nucleon spin-independent parameter space for WIMP masses below 6 GeV/c2.

  8. Thermodynamic properties of illite, smectite and beidellite by calorimetric methods: Enthalpies of formation, heat capacities, entropies and Gibbs free energies of formation

    NASA Astrophysics Data System (ADS)

    Gailhanou, H.; Blanc, P.; Rogez, J.; Mikaelian, G.; Kawaji, H.; Olives, J.; Amouric, M.; Denoyel, R.; Bourrelly, S.; Montouillout, V.; Vieillard, P.; Fialips, C. I.; Michau, N.; Gaucher, E. C.

    2012-07-01

    The thermodynamic properties of three aluminous 2:1 clay minerals were acquired at 1.013 bars and at temperatures between 5 and 500 K using various calorimetric methods. Calorimetric measurements were performed on hydrated and dehydrated <2 μm clay fractions of smectite MX-80 (Wyoming), illite IMt-2 (Silver Hill) and beidellite SBId-1 (Black Jack Mine). After purification, the mineralogical analyses gave the following structural formulae: Na0.409K0.024Ca0.009 (Si3.738Al0.262) (Al1.598Mg0.214Fe 0.173 3 + Fe 0.035 2 +)O10(OH)2,K0.762Na0.044 (Si3.387Al0.613) (Al1.427Mg0.241Fe 0.292 3 + Fe 0.084 2 +)O10(OH)2 and Ca0.185K0.104 (Si3.574Al0.426) (Al1.812Mg0.09Fe 0.112 3 +)O10(OH)2 for smectite MX-80, illite IMt-2 and beidellite SBId-1, respectively. Heat capacities were measured by low temperature adiabatic calorimetry and differential scanning calorimetry, from 5 to 500 K. Standard enthalpies of formation were obtained from solution-reaction calorimetry at 298.15 K. The standard Gibbs free energies of formation of the clay minerals were also calculated, together with the equilibrium constants at 25 °C, for anhydrous and hydrated minerals. A comparison between these experimental data and estimated values obtained from prediction models available in the literature, enabled the calculation method that appears to be the most relevant to be selected, at least for aluminous 2:1 clay minerals.

  9. La reconstruction du sourcil par greffon composite du cuir chevelu: une astuce pour faciliter la technique

    PubMed Central

    El Omari, Mounia; El Mazouz, Samir; Gharib, Noureddine; EL Abbassi, Abdallah

    2015-01-01

    Les sourcils jouent un rôle important dans l’équilibre esthétique du visage. Leur reconstruction ou ophriopoïése, après séquelle de brûlure fait partie intégrante du programme de réhabilitation de la face brûlée. Plusieurs techniques ont été décrites. Nous insistons ici sur l'intérêt d'une technique simple, à la portée de tous les chirurgiens, et dont la méthode et les résultats peuvent être améliorés par un dessin bien planifié des zones donneuse et receveuse: la greffe composite prélevée au niveau du cuir chevelu dessinée à l'aide d'un calque du sourcil controlatéral. PMID:26401195

  10. 33 CFR 117.443 - Du Large Bayou.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Du Large Bayou. 117.443 Section 117.443 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.443 Du Large Bayou. The draw of...

  11. 76 FR 68124 - Television Broadcasting Services; Fond du Lac, WI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-03

    ... reconsideration of an August 12, 2009 Report and Order changing the allotted channel for station WWAZ-TV, Fond du... 5 for channel 44 at Fond du Lac ] because it permitted WLS-TV, an ABC network affiliate in Chicago... network service to numerous viewers that had lost service after the transition of WLS-TV to...

  12. Oncoplastie avec conservation mammaire dans le traitement du cancer du sein: à propos de 16 cas

    PubMed Central

    Bouzoubaa, Wail; Laadioui, Meryam; Jayi, Sofia; Alaoui, Fatime Zahra Fdili; Bouguern, Hakima; Chaara, Hikmat; Melhouf, Moulay Abdelilah

    2015-01-01

    Le cancer du sein est actuellement le cancer le plus fréquent chez la femme, et pose un véritable problème diagnostique et thérapeutique. Le dépistage des lésions à un stade de plus en plus précoce, a permis une extension des indications du traitement conservateur radiochirurgical, qui était initialement limitées aux tumeurs de moins de 3 cm, unifocales, non inflammatoires. Par ailleurs, l'utilisation de traitements préopératoires permet d’étendre les indications du traitement conservateur à des tumeurs plus volumineuses. Parallèlement à cette extension des indications de conservation mammaire, on a observé le développement de nouvelles approches thérapeutiques notamment la chirurgie oncoplastique, technique du ganglion sentinelle et chirurgie stéréotaxique, dont les résultats initiaux sont très encouragent. A travers cette étude réalisée dans le service de gynécologie et obstétrique II du CHU HASSAN II de FES au MAROC, après l'analyse rétrospective de 16 patientes traitées par traitement conservateur et oncoplastie, nous avons voulus montrer notre aptitude a réalisé ses techniques chirurgicales et a bien prendre en charge ces patientes, mais aussi évaluer ces techniques en termes de résultat carcinologique et de résultat esthétique, aussi en terme de survie globale, survie sans métastase et en termes de récidive locale entre les plasties mammaires et les traitements usuels: mastectomie et traitement conservateur classique. PMID:26430477

  13. Modelisation par elements finis du muscle strie

    NASA Astrophysics Data System (ADS)

    Leonard, Mathieu

    Ce present projet de recherche a permis. de creer un modele par elements finis du muscle strie humain dans le but d'etudier les mecanismes engendrant les lesions musculaires traumatiques. Ce modele constitue une plate-forme numerique capable de discerner l'influence des proprietes mecaniques des fascias et de la cellule musculaire sur le comportement dynamique du muscle lors d'une contraction excentrique, notamment le module de Young et le module de cisaillement de la couche de tissu conjonctif, l'orientation des fibres de collagene de cette membrane et le coefficient de poisson du muscle. La caracterisation experimentale in vitro de ces parametres pour des vitesses de deformation elevees a partir de muscles stries humains actifs est essentielle pour l'etude de lesions musculaires traumatiques. Le modele numerique developpe est capable de modeliser la contraction musculaire comme une transition de phase de la cellule musculaire par un changement de raideur et de volume a l'aide des lois de comportement de materiau predefinies dans le logiciel LS-DYNA (v971, Livermore Software Technology Corporation, Livermore, CA, USA). Le present projet de recherche introduit donc un phenomene physiologique qui pourrait expliquer des blessures musculaires courantes (crampes, courbatures, claquages, etc.), mais aussi des maladies ou desordres touchant le tissu conjonctif comme les collagenoses et la dystrophie musculaire. La predominance de blessures musculaires lors de contractions excentriques est egalement exposee. Le modele developpe dans ce projet de recherche met ainsi a l'avant-scene le concept de transition de phase ouvrant la porte au developpement de nouvelles technologies pour l'activation musculaire chez les personnes atteintes de paraplegie ou de muscles artificiels compacts pour l'elaboration de protheses ou d'exosquelettes. Mots-cles Muscle strie, lesion musculaire, fascia, contraction excentrique, modele par elements finis, transition de phase

  14. Continuous improvement journey at Du Pont photomasks

    NASA Astrophysics Data System (ADS)

    Henderson, Robert K.

    1994-02-01

    This paper describes the history and experiences of Du Pont Photomasks in their efforts to integrate the continuous improvement philosophy and practices embodied in the Malcolm Baldrige National Quality Award criteria into their way of doing business. A case study of key learnings in this almost four year long process is presented. Specific topics discussed include the process applied to achieve ISO 9000 certification, the quality systems deployed in this effort, and the use of a balanced set of business and quality metrics to assess and improve upon performance.

  15. La fin du jeûne?

    PubMed Central

    Naugler, Christopher; Sidhu, Davinder

    2014-01-01

    Résumé Objectif Présenter une mise à jour sur l’utilité clinique de ne pas être à jeun par rapport à l’être pour l’analyse des lipides dans le but d’améliorer l’observance par les patients, leur sécurité et l’évaluation clinique dans les tests du cholestérol. Qualité des données Les recommandations sont classées comme étant fondées sur des données probantes fortes, acceptables ou faibles (conflictuelles ou insuffisantes), selon les classifications adoptées par le Groupe d’étude canadien sur les soins de santé préventifs. Message principal Le dépistage de la dyslipidémie comme facteur de risque de coronaropathie et la prescription de médicaments hypolipidémiants sont des activités importantes en soins primaires. De récentes données probantes remettent en question la nécessité d’être à jeun pour la mesure des lipides. Dans des études sur la population, le cholestérol total, le cholestérol à lipoprotéines de haute densité et le cholestérol à lipoprotéines autres qu’à haute densité variaient tous d’en moyenne 2 % à jeun. Pour un dépistage de routine, la mesure du cholestérol sans être à jeun est maintenant une option de rechange raisonnable à l’analyse à jeun. Pour les patients diabétiques, l’exigence d’être à jeun peut représenter un important problème de sécurité en raison des possibilités d’hypoglycémie. Pour la surveillance des triglycérides et du cholestérol à lipoprotéines de basse densité chez les patients qui prennent des médicaments hypolipidémiants, le jeûne devient important. Conclusion Être à jeun pour la détermination routinière des niveaux lipidiques est largement inutile et il est improbable que le jeûne influence la stratification du risque clinique chez le patient, tandis que la mesure sans être à jeun pourrait améliorer l’observance par le patient et sa sécurité.

  16. Mesure du taux de la capture radiative du muon par l'hydrogene liquide

    NASA Astrophysics Data System (ADS)

    Jonkmans, Guy

    À basse énergie, l'interaction faible entre leptons et quarks est décrite par une interaction de la forme courant × courant de type V - A. La présence de l'interaction forte induit des couplages additionnels qui doivent être déterminés expérimentalement. De ceux-ci, le couplage pseudoscalaire induit, gp , est mesuré avec la plus grande incertitude et fait l'objet de la présente recherche. L'hypothèse du Courant Axial Partiellement Conservé (CAPC) et l'usage de la relation de Goldberger-Treiman relie gp au couplage axial ga . Cette relation a été vérifiée traditionnellement par la Capture Ordinaire du Muon (COM) à une valeur fixe du moment de transfert q. La Capture Radiative du Muon (CRM), m- p-->nnmg , est un meilleur outil pour l'étude de gp à cause de sa dépendance variable en q2 qui offre une plus grande sensibilité dans la partie à haute énergie du spectre des photons. Toutefois, le petit rapport d'embranchement (~10-8) de la CRM par rapport à la désintégration du muon a retardé cette mesure jusqu'à ce jour. La théorie et les difficultés expérimentales associées à la détection des photons de CRM sont présentées au deuxième chapitre. On décrit ensuite, au troisième chapitre, les composantes du système de détection. Ce détecteur est un spectromètre à paires de grand angle solide (~3p) et qui permet l'observation des photons par l'analyse des électrons et des positrons de photo-conversion. Ainsi, le bruit de fond important des neutrons de la COM ne constitue pas un problème pour cette mesure. Nous décrivons, au quatrième chapitre, toutes les étapes de l'analyse, nécessaires pour la réduction des multiples bruits de fond. Le cinquième chapitre présente le calcul des efficacités ainsi que l'estimation des erreurs systématiques. Le sixième chapitre démontre comment l'on extrait le rapport d'embranchement pour la CRM ainsi que la valeur ae gp . On insiste sur la dépendance de gp en fonction de la valeur de

  17. The Pic du Midi solar survey

    NASA Astrophysics Data System (ADS)

    Koechlin, L.

    2015-12-01

    We carry a long term survey of the solar activity with our coronagraphic system at Pic du Midi de Bigorre in the French Pyrenees (CLIMSO). It is a set of two solar telescopes and two coronagraphs, taking one frame per minute for each of the four channels : Solar disk in H-α (656.28 nm), prominences in H-α, disk in Ca II (393.3 nm), prominences in He I (1083 nm), all year long, weather permitting. Since 2015 we also take images of the FeXIII corona (1074.7 nm) at the rate of one every 10 minutes. These images cover a large field: 1.25 solar diameter, 2k*2K pixels, and are freely downloadable form a database. The improvements made since 2015 concern an autoguiding system for better centering of the solar disk behind the coronagraphic masks, and a new Fe XIII channel at λ=1074.7 nm. In the near future we plan to provide radial velocity maps of the disc and polarimetry maps of the disk and corona. This survey took its present form in 2007 and we plan to maintain image acquisition in the same or better experimental conditions for a long period: one or several solar cycles if possible. During the partial solar eclipse of March 20, 2015, the CLIMSO instruments and the staff at Pic du Midi operating it have provided several millions internet users with real time images of the Sun and Moon during all the phenomenon.

  18. Élimination du bore du silicium par plasma inductif sous champ électrique

    NASA Astrophysics Data System (ADS)

    Combes, R.; Morvan, D.; Picard, G.; Amouroux, J.

    1993-05-01

    We analyzed purification mechanisms of silicon by inductive plasma with a fluoride slag. The aim is to study boron elimination from doped electronic grade silicon in function of the nature of the slag to obtain a photovoltaic grade silicon. The steady began with the calculation and the comparison of the stability diagram of boron compounds in presence of CaF2, BaF2 and MgF2. This study led us to conclude that BaF2 is the better slag for silicon purification. This has been confirmed by experience. In a second time, we made purifications under electric bias to enhance slag efficiency. We noticed that BaF2 is more sensitive to electric bias than other slags. Nous avons analysé le mécanisme de purification du silicium sous plasma inductif en présence d'un laitier fluoré. L'objectif principal est d'étudier l'élimination du bore du silicium électronique dopé en fonction de la nature du fluorure pour obtenir un silicium de qualité photovoltaïque. L'étude a commencé par l'établissement et la comparaison de diagrammes des composés du bore en présence de CaF2, de MgF2 et de BaF2. Nous avons déduit de cette première étude que BaF2 est le meilleur laitier pour la purification du silicium. Ceci a été corroboré par l'expérience. Nous avons ensuite opéré en présence d'un champ électrique dans le but d'améliorer encore l'efficacité des laitiers. Nous avons constaté que BaF2 est plus sensible au champ électrique que les deux autres laitiers utilisés.

  19. Annuaire du Bureau des longitudes - 2006

    NASA Astrophysics Data System (ADS)

    Imcce; Bureau Des Longitudes

    2005-07-01

    This annual publication provides ephemerides and data to the use of professionnal and amateur astronomers. Divided in 11 chapters it covers concordance of various calendars, explanation of fondamental astronomy and various time scales, explanation for the use of ephemerides; tables provide ephemerides (positions, rise/set/passage) of the Sun and the Moon, planets, planetary satellites, asteroids, comets, bright stars; data and explanation for the physical observation of the surface of the Sun, the Moon, and planets; chart of the sky and a list of constellations and galaxies; prediction and ephemerides for astronomical phenomenon: occultation by the moon, stellar occultations by asteroids and appulses, solar eclipses and lunar eclipses; and an additional review about a hot scientific topic, this year: "Legendre et le méridien terrestre, 200 ans après". Cette publication annuelle fournit des éphémérides et des données à l'usage des astronomes professionnels et des astronomes amateurs. Composée de 11 chapitres elle comprend les rubriques sur les différents calendriers et leurs concordance, les fêtes légales en France, les dates et décrets sur les heures légales en France métropolitaine ; une introduction à l'astronomie fondamentale et aux différentes échelles de temps, des explications sur l'utilisation des éphémérides ; des tables fournissent les éphémérides (positions, heures de lever/coucher/passage) du Soleil et de la Lune, de planètes, de satellites naturels, d'astéroïdes, de comètes, d'étoiles brillantes ; des données pour l'observation de la surface du Soleil, de la Lune, et des planètes ; des cartes du ciel ainsi qu'une liste de constellations et de galaxies ; des prédictions des phénomènes astronomiques : occultation par la Lune, occultation stellaires par des astéroïdes et appulses, éclipses de Soleil et de la Lune; la liste et les coordonnées des observatoires astronomiques les plus connus ; et enfin un cahier th

  20. Carte du Ciel, San Fernando zone

    NASA Astrophysics Data System (ADS)

    Abad, C.

    2014-06-01

    An updated summary of a future large astrometric catalogue is presented, based on the two most important astrometric projects carried out by the Real Instituto y Observatorio de la Armada de San Fernando (ROA). The goal is to make a catalogue of positions and proper motions based on ROA's Cart du Ciel (CdC) and the Astrographic Catalogue (AC) San Fernando zone plates, and the HAMC2 meridian circle catalogue. The CdC and AC plates are being reduced together to provide first-epoch positions while HAMC2 will provide second-epoch ones. New techniques have been applied, that range from using a commercial flatbed scanner to the proper reduction schemes to avoid systematics from it. Only thirty plates (out of 540) remain to be processed, due to scanning problems that are being solved.

  1. Le mouvement du pôle

    NASA Astrophysics Data System (ADS)

    Bizouard, Christian

    2012-03-01

    Les variations de la rotation terrestre. En conditionnant à la fois notre vie quotidienne, notre perception du ciel, et bon nombre de phénomènes géophysiques comme la formation des cyclones, la rotation de la Terre se trouve au croisement de plusieurs disciplines. Si le phenomena se faisait uniformément, le sujet serait vite discuté, mais c'est parce que la rotation terrestre varie, même imperceptiblement pour nos sens, dans sa vitesse angulaire comme dans la direction de son axe, qu'elle suscite un grand intérêt. D'abord pour des raisons pratiques : non seulement les aléas de la rotation terrestre modi_ent à la longue les pointés astrométriques à un instant donné de la journée mais in_uencent aussi les mesures opérées par les techniques spatiales ; en consequence l'exploitation de ces mesures, par exemple pour déterminer les orbites des satellites impliqués ou pratiquer le positionnement au sol, nécessite une connaissance précise de ces variations. Plus fondamentalement, elles traduisent les propriétés globales de la Terre comme les processus physiques qui s'y déroulent, si bien qu'en analysant les causes des fluctuations observées, on dispose d'un moyen de mieux connaître notre globe. La découverte progressive des fluctuations de la rotation de la Terre a une longue histoire. Sous l'angle des techniques d'observation, trois époques se pro-celle du pointé astrométrique à l'oeil nu, à l'aide d'instruments en bois ou métalliques (quart de cercle muraux par exemple). À partir du XVIIe siècle débute l'astrométrie télescopique dont les pointés sont complétés par des datations de plus en plus précises grâce à l'invention d'horloges régulées par balancier. Cette deuxième époque se termine vers 1960, avec l'avènement des techniques spatiales : les pointés astrométriques sont délaissés au profit de la mesure ultra-précise de durées ou de fréquences de signaux électromagnétiques, grâce à l'invention des horloges

  2. Notable Stabilization of α-Chymotrypsin by the Protic Ionic Additive, [ch][dhp]: Calorimetric Evidence for a Fine Enthalpy/Entropy Balance

    PubMed Central

    Makharadze, Maya; van Eldik, Rudi; Khoshtariya, Dimitri E.

    2014-01-01

    An impact of 0.5 to 3 M choline dihydrogen phosphate, [ch][dhp], the biotechnologically relevant ionic substance, on the thermal stability of a model globular protein, α-chymotrypsin (α-CT), has been studied exploiting the highly sensitive differential scanning calorimetry (DSC) technique. The notable overall stabilizing effect of 11 ± 2 K regarding the thermal transition (melting) temperature, Tm, has been detected. For this kind of series, for the first time, the calorimetric melting enthalpy (ΔHcal) and transition entropy (ΔSm) parameters have been determined simultaneously throughout. The first analysis indicated a two-phase impact implying (a) the initial, dramatic drop in both ΔHcal and ΔSm, obviously connected to specific, direct interaction between the [ch][dhp] components and α-CT's charged groups (within 0 to 1 mol/L [ch][dhp]), leading to the essential rearrangement of the interfacial hydrogen-bonded (HB) network; and (b) the follow-up (within 1 to 3.0 mol/L [ch][dhp]), modest changes in ΔHcal and lack of changes in ΔSm, seemingly connected with a subsequent steady strengthening of already reformed HB network, respectively. These changes, presumably, are primarily facilitated by Coulombic interactions between the [dhp] anions and solvent-exposed positively charged amino groups of α-CT.

  3. Calorimetric study of crystal growth of ice in hydrated methemoglobin and of redistribution of the water clusters formed on melting the ice.

    PubMed Central

    Sartor, G; Mayer, E

    1994-01-01

    Calorimetric studies of the melting patterns of ice in hydrated methemoglobin powders containing between 0.43 and 0.58 (g water)/(g protein), and of their dependence on annealing at subzero temperatures and on isothermal treatment at ambient temperature are reported. Cooling rates were varied between approximately 1500 and 5 K min-1 and heating rate was 30 K min-1. Recrystallization of ice during annealing is observed at T > 228 K. The melting patterns of annealed samples are characteristically different from those of unannealed samples by the shifting of the melting temperature of the recrystallized ice fraction to higher temperatures toward the value of "bulk" ice. The "large" ice crystals formed during recrystallization melt on heating into "large" clusters of water whose redistribution and apparent equilibration is followed as a function of time and/or temperature by comparison with melting endotherms. We have also studied the effect of cooling rate on the melting pattern of ice with a methemoglobin sample containing 0.50 (g water)/(g protein), and we surmise that for this hydration cooling at rates of > or = approximately 150 K min-1 preserves on the whole the distribution of water molecules present at ambient temperature. PMID:7819504

  4. Classification moléculaire du cancer du sein au Maroc

    PubMed Central

    Fouad, Abbass; Yousra, Akasbi; Kaoutar, Znati; Omar, El Mesbahi; Afaf, Amarti; Sanae, Bennis

    2012-01-01

    Introduction La classification moléculaire des cancers du sein basée sur l'expression génique puis sur le profil protéique a permis de distinguer cinq groupes moléculaires: luminal A, luminal B, Her2/neu, basal-like et non-classées. L'objectif de cette étude réalisée au CHU Hassan II de Fès est de classer 335 cancers du sein infiltrant en groupes moléculaires, puis de les corréler avec les caractéristiques clinicopathologiques. Méthodes Etude rétrospective étalée sur 45 mois, comportant 335 patientes colligées au CHU pour le diagnostic et le suivi. Les tumeurs sont analysées histologiquement et classées après une étude immunohistochimique en groupes: luminal A, luminal B, Her2+, basal-like et non-classées. Résultats 54.3% des tumeurs sont du groupe luminal A, 16% luminal B, 11.3% Her2+, 11.3% basal-like et 7% non-classées. Le groupe luminal A renferme le plus faible taux de grade III, d'emboles vasculaires ainsi que de métastases; alors que le groupe des non-classées et basal-like représentent un taux élevé de grade III, une faible proportion d'emboles vasculaires et d'envahissement ganglionnaire. Ces facteurs sont significativement élevés dans les groupes luminal B et Her2+ avec un taux de survie globale de 78% et 76% respectivement. Dans le groupe luminal A, la survie globale des patientes est élevée (87%) alors qu'elle n'est que de 49% dans le groupe des triples négatifs (basal-like et non-classés). Conclusion Le groupe luminal B est différent du luminal A et il est de pronostic péjoratif vis à vis du groupe Her2+. Les caractéristiques clinicopathologiques concordent avec le profil moléculaire donc devraient être pris en considération comme facteurs pronostiques. PMID:23396646

  5. 1. Historic American Buildings Survey, drawn by Pierre du Simitiere ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, drawn by Pierre du Simitiere (papers in Philadelphia Library) DRAWING OF REDWOOD LIBRARY IN 1768. - Redwood Library, 50 Bellevue Avenue, Newport, Newport County, RI

  6. Oxidation states of uranium in DU particles from Kosovo.

    PubMed

    Salbu, B; Janssens, K; Lind, O C; Proost, K; Danesi, P R

    2003-01-01

    The oxidation states of uranium contained in depleted uranium (DU) particles were determined by synchrotron radiation based micro-XANES, applied to individual particles in soil samples collected at Ceja Mountain, Kosovo. Based on scanning electron microscopy (SEM) with XRMA prior to micro-XANES, DU particles ranging from submicrons to about 30 microm (average size: 2 microm or less) were identified. Compared to well-defined standards, all investigated DU particles were oxidized. About 50% of the DU particles were characterized as UO2, the remaining DU particles present were U3O8 or a mixture of oxidized forms (ca. 2/3 UO2, 1/3 U3O8). Since the particle weathering rate is expected to be higher for U3O8 than for UO2, the presence of respiratory U3O8 and UO2 particles, their corresponding weathering rates and subsequent remobilisation of U from DU particles should be included in the environmental or health impact assessments. PMID:12500803

  7. Tumeur du sac vitellin du testicule au stade IIIc métastatique : à propos d’un cas

    PubMed Central

    Zizi, Mohamed; Ziouziou, Imad; El Yacoubi, Souhail; Khmou, Mouna; Jahid, Ahmed; Mahassini, Najat; Karmouni, Tariq; El Khader, Khalid; Koutani, Abdellatif; Andaloussi, Ahmed Iben Attya

    2014-01-01

    Résumé Les tumeurs du sac vitellin du testicule sont rares chez l’adulte. Ces tumeurs se caractérisent par un mauvais pronostic à un stade métastatique avancé. Cependant, nous rapportons, dans le présent article, le cas clinique d’un adulte de 32 ans qui présentait une tumeur du sac vitellin du testicule au stade IIIc métastatique. Ce patient a subi une orchidectomie haute, accompagnée de quatre cycles de chimiothérapie à base de bléomycine, d’étoposide et de cisplatine. Il a répondu complètement au traitement, moyennant un recul de deux ans. PMID:25295144

  8. Gibbs free energies of formation of RuO 2, IrO 2, and OsO 2: A high-temperature electrochemical and calorimetric study

    NASA Astrophysics Data System (ADS)

    O'Neill, Hugh St. C.; Nell, Johan

    1997-12-01

    The Gibbs free energies of formation of RuO 2, OsO 2 and IrO 2 have been determined by measuring the chemical potentials of oxygen (μO 2) defined by the reactions M + O 2 = MO 2, where M = Ru, Os. or Ir, using an electrochemical method with calcia-stabilized zirconia (CSZ) solid electrolytes. Measurements were attempted in the temperature ranges from ˜870 K to 1620, 1270, and 1415 K for the Ru, Os, and Ir equilibria, respectively, but inspection of the results reveals that equilibrium could not be established below ˜930 K for all three reactions. For Ru + RuO 2, the highest temperature data (above 1520 K) may be systematically affected by the onset of significant electronic conduction in the CSZ electrolyte, while the attempted measurements of the Os + OsO 2 equilibrium above 1190 K are obscured by the disproportionation of OsO 2 to gaseous Os oxides. The high temperature heat capacities at constant pressure ( Cp) of RuO 2 and IrO 2 were determined from 370 to 1070 K by differential scanning calorimetry. These data were combined with heat content measurements and low-temperature heat capacities from the literature, and fitted to an extended Maier-Kelley equation. The calorimetric data for RuO 2 and IrO 2, together with assessed data for Ru, Os, and Ir metals and estimated data for OsO 2, were used in a third law analysis of the electrochemical measurements. The values of μO 2 of the three equilibria were smoothed and filtered by the third-law analysis to yield the following equations which can be extrapolated to lower and higher temperatures as indicated: μO 2 ( Ru + RuO 2) = -324563 + 344.151 T-22.1155 T ln T (700 ⩽ T ⩽ 1800) μO 2 ( Os + OsO 2) = -300399 + 307.639 T-17.4819 T ln T (700 ⩽ T ⩽ 1500) μO 2 ( Ir + IrO 2) = -256518 + 295.854 T-15.2368 T ln T (700 ⩽ T ⩽ 1500) where μO 2 is in J mol -1, T is in K, the reference pressure for O 2 is 1 bar (10 5 Pa), and estimated accuracies are approximately 200 to 400 J mol -1. For Ru + RuO 2, the drift

  9. Calorimetric analysis of thermodynamic stability and aggregation for apo and holo amyotrophic lateral sclerosis-associated Gly-93 mutants of superoxide dismutase.

    PubMed

    Stathopulos, Peter B; Rumfeldt, Jessica A O; Karbassi, Farhad; Siddall, Clare A; Lepock, James R; Meiering, Elizabeth M

    2006-03-10

    Differential scanning calorimetry was used to measure changes in thermodynamic stability and aggregation for glycine 93 mutants of human copper, zinc-superoxide dismutase (SOD). Glycine 93 is a conserved residue at position i + 3 of a tight turn and has been found to be a mutational hot spot in familial amyotrophic lateral sclerosis (fALS). The fALS-associated mutations, G93A, G93S, G93R, G93D, and G93V, were made in a pseudo wild-type background containing no free cysteines, which prevented the formation of aberrant disulfide bonds upon thermal unfolding, and enabled quantitative thermodynamic analysis of the effects of the mutations. Thermal unfolding was highly reversible for all the SODs in both the fully metallated (holo) and metal-free (apo) forms. The data for all the holo-SODs and for the apo-pseudo-wild-type SOD were well fit by a 2-state unfolding model for native dimer (N2) to two unfolded monomers (2U), N2 <--> 2U. The holo- and apo-forms of the mutants are significantly destabilized (by 1.5-3.5 kcal mol(-1) monomer) relative to the corresponding forms of pseudo wild-type, with the relative stabilities being correlated with statistical preferences for amino acids in this structural context. Although van't Hoff (DeltaHvH) to calorimetric (DeltaHcal) enthalpy ratios are close to unity for all the holo-SODs and for apo-pseudo-wild-type, consistent with a 2-state transition, DeltaHvH is considerably larger than DeltaHcal for all the apo-mutants. This suggests that the mutations cause apo-SOD to have an increased propensity to misfold or aggregate, which may be linked to increased toxic mutant SOD aggregation in fALS. PMID:16407238

  10. Thermodynamic, structural, and dynamic properties of supercooled water confined in mesoporous MCM-41 studied with calorimetric, neutron diffraction, and neutron spin echo measurements

    NASA Astrophysics Data System (ADS)

    Yoshida, Koji; Yamaguchi, Toshio; Kittaka, Shigeharu; Bellissent-Funel, Marie-Claire; Fouquet, Peter

    2008-08-01

    Thermodynamic, structural, and dynamic properties of heavy water (D2O) confined in mesoporous silica glass MCM-41 C10, C12, and C14 were investigated by differential scanning calorimetry, neutron diffraction, and neutron spin echo (NSE) measurements, respectively. The DSC data showed that no crystallization of D2O confined in C10 occurs in a temperature range between 298 and 180 K, and that crystalline ice is formed at 204 and 221 K for C12 and C14, respectively. For C10, the neutron radial distribution functions of confined D2O suggested a structural change in the supercooled state between 223 and 173 K. For C10 sample, it has been found that the tetrahedral-like water structure is partially enhanced in the central part of pores at 173 K. For all the samples, the intermediate scattering functions from the NSE measurements are fitted by the Kohlrausch-Williams-Watts stretched exponential function which implies that confined supercooled D2O exhibits a wide distribution of relaxation times. For C10, C12, and C14 samples, between 298 and 240 K, the relaxation times of supercooled D2O follow remarkably well the Vogel-Fulcher-Tamman equation; for C10 sample, below 240 K, the relaxation times of nonfreezing D2O show an Arrhenius type behavior. From the present experimental results on calorimetric, structural, and dynamic properties, it has been concluded that supercooled D2O confined in MCM-41 C10 experiences a transition from high-density to low-density hydrogen-bonded structure at around 229 K.

  11. Interaction of cationic dodecyl-trimethyl-ammonium bromide with oxy-HbGp by isothermal titration and differential scanning calorimetric studies: Effect of proximity of isoelectric point.

    PubMed

    Alves, Fernanda Rosa; Carvalho, Francisco Adriano O; Carvalho, José Wilson P; Tabak, Marcel

    2016-04-01

    In this work, isothermal titration and differential scanning calorimetric methods, in combination with pyrene fluorescence emission and dynamic light scattering have been used to investigate the interaction of dodecyltrimethylammonium bromide (DTAB) with the giant extracellular Glossoscolex paulistus hemoglobin (HbGp) in the oxy-form, at pH values around the isoelectric point (pI ≈ 5.5). Our ITC results have shown that the interaction of DTAB with the hemoglobin is more intense at pH 7.0, with a smaller cac (critical aggregation concentration) value. The increase of protein concentration does not influence the cac value of the interaction, at both pH values. Therefore, the beginning of the DTAB-oxy-HbGp premicellar aggregates formation, in the cac region, is not affected by the increase of protein concentration. HSDSC studies show higher Tm values at pH 5.0, in the absence and presence of DTAB, when compared with pH 7.0. Furthermore, at pH 7.0, an aggregation process is observed with DTAB in the range from 0.75 to 1.5 mmol/L, noticed by the exothermic peak, and similar to that observed for pure oxy-HbGp, at pH 5.0, and in the presence of DTAB. DLS melting curves show a decrease on the hemoglobin thermal stability for the oxy-HbGp-DTAB mixtures and formation of larger aggregates, at pH 7.0. Our present data, together with previous results, support the observation that the protein structural changes, at pH 7.0, occur at smaller DTAB concentrations, as compared with pH 5.0, due to the acidic pI of protein that favors the oxy-HbGp-cationic surfactant interaction at neutral pH. PMID:26574155

  12. Calorimetric study of the effect of bent-shaped dopant molecules on the critical behavior at the nematic-smectic-Ad phase transition

    NASA Astrophysics Data System (ADS)

    Sasaki, Y.; Ema, K.; Le, K. V.; Takezoe, H.; Dhara, S.; Sadashiva, B. K.

    2011-06-01

    We report results of calorimetric studies for the binary mixture of rodlike host n-alkyloxy-cyanobiphenyl (nOCB, n=8,9) and bent-shaped guest 1,3-phenylene-bis[4-(3-methylbenzoyloxy)]-4'-n-dodecylbiphenyl-4'-carboxylate (BC12). The effect of bent-shaped dopant molecules on the critical behavior associated with the nematic-smectic-Ad phase transition has been studied in detail. The transition temperature for the nematic-smectic-Ad phase sharply decreases as the increase of the mole fraction of the dopant concentration (denoted X for the BC12/9OCB mixture and Y for the BC12/8OCB mixture). The dependence of the critical exponent α on X and Y is well explained in terms of the McMillan ratio. A nearly tricritical exponent has been obtained for the X=0.01 mixture. X=0.02-0.03 mixtures, pure 8OCB, and Y=0.01-0.03 mixtures exhibit nonuniversal behaviors with effective exponents lying between the 3D-XY and tricritical exponents. The heat capacity anomaly for Y=0.05 has been well described with the 3D-XY exponent. The critical amplitude ratio A-/A+ is close to 1 and insensitive to the dopant concentration. No Fisher renormalization of the critical exponent has been observed even for nearly tricritical compositions, which indicates the smallness of the concentration plays a decisive role rather than the steepness of the N-SmAd phase boundary.

  13. Mise à jour sur le nouveau vaccin 9-valent pour la prévention du virus du papillome humain

    PubMed Central

    Yang, David Yi; Bracken, Keyna

    2016-01-01

    Résumé Objectif Informer les médecins de famille quant à l’efficacité, à l’innocuité, aux effets sur la santé publique et à la rentabilité du vaccin 9-valent contre le virus du papillome humain (VPH). Qualité des données Des articles pertinents publiés dans PubMed jusqu’en mai 2015 ont été examinés et analysés. La plupart des données citées sont de niveau I (essais randomisés et contrôlés et méta-analyses) ou de niveau II (études transversales, cas-témoins et épidémiologiques). Des rapports et recommandations du gouvernement sont aussi cités en référence. Message principal Le vaccin 9-valent contre le VPH, qui offre une protection contre les types 6, 11, 16, 18, 31, 33, 45, 52 et 58 du VPH, est sûr et efficace et réduira encore plus l’incidence des infections à VPH, de même que les cas de cancer lié au VPH. Il peut également protéger indirectement les personnes non immunisées par l’entremise du phénomène d’immunité collective. Un programme d’immunisation efficace peut prévenir la plupart des cancers du col de l’utérus. Les analyses montrent que la rentabilité du vaccin 9-valent chez les femmes est comparable à celle du vaccin quadrivalent original contre le VPH (qui protège contre les types 6, 11, 16 et 18 du VPH) en usage à l’heure actuelle. Toutefois, il faut investiguer plus en profondeur l’utilité d’immuniser les garçons avec le vaccin 9-valent contre le VPH. Conclusion en plus d’être sûr, le vaccin 9-valent protège mieux contre le VPH que le vaccin quadrivalent. Une analyse coûtefficacité en favorise l’emploi, du moins chez les adolescentes. Ainsi, les médecins devraient recommander le vaccin 9-valent à leurs patients plutôt que le vaccin quadrivalent contre le VPH.

  14. Le kyste hydatique du cordon spermatique: une localisation exceptionnelle

    PubMed Central

    Hamdane, Mohamed Moncef; Bougrine, Fethi; Msakni, Issam; Dhaoui-Ghozzi, Amen; Bouziani, Ammar

    2011-01-01

    L’ hydatidose est une anthropo-zoonose due au développement chez l'homme de la forme larvaire du taenia Echinococcus granulosis. La plupart des kystes hydatiques se localisent dans le foie et les poumons. Le kyste hydatique du cordon spermatique est extrêmement rare avec seulement 4 cas rapportés dans la littérature. Les auteurs rapportent dans cet article un nouveau cas d'hydatidose du cordon spermatique. Il s'agissait d'un homme de 40 ans qui consultait pour des douleurs scrotales évoluant depuis huit mois. L'examen clinique a mis en évidence une tuméfaction mobile, inguino-scrotale, droite. L’échographie testiculaire a objectivé une hernie inguinale droite associée à deux kystes épididymaires bilatéraux. Le patient a été opéré pour cure de son hernie avec découverte en per-opératoire d'un kyste du cordon spermatique qui a été réséqué. L'examen anatomopathologique a conclu à une hydatidose du cordon spermatique. PMID:22384304

  15. Modelisation du Signal Radar EN Milieu Stratifie et Evaluation de Techniques de Mesure de L'humidite du Sol

    NASA Astrophysics Data System (ADS)

    Boisvert, Johanne

    La presente etude se penche sur des problemes relies a l'echantillonnage de l'humidite de sol et a l'estimation du signal radar sur sols nus. Le travail se divise en deux volets. Le volet 1 evalue trois techniques de mesure de l'humidite du sol (gravimetrie, reflectometrie temporelle et sonde dielectrique) et deux protocoles d'echantillonnage. Dans le volet 2, un modele de simulation du signal en milieu stratifie est developpe, et les estimes de signal obtenus sont compares aux estimes bases uniquement sur une valeur moyenne d'humidite du sol prise sur une profondeur fixe d'echantillonnage. Les differences entre les deux estimes dependent de la frequence et du choix judicieux de la profondeur d'echantillonnage; elles sont plus importantes aux faibles angles et en polarisation HV, puis VV. Le modele de simulation a aussi ete utilise pour etudier la profondeur de penetration du signal et en deduire la profondeur optimale d'echantillonnage en tenant compte des caracteristiques du signal. Une variation de 25 ^circ de l'angle d'incidence a peu d'effet sur la profondeur de penetration en bande Ku; l'ecart reste inferieur ou egal a 0,5 cm en bande C mais peut atteindre 1,3 cm en bande L. L'impact de la polarisation est nul en bande Ku mais croi t avec l'angle d'incidence en bande C et L. A 50^circ, il est, en moyenne de 1 cm en bande C et de 2 cm en bande L. En polarisation VV, la profondeur croi t avec une augmentation de l'angle alors que l'effet est inverse en polarisation HH. Deux methodes pour estimer la profondeur d'echantillonnage en conditions operationnelles sont presentees. Lorsqu'on inverse un modele pour estimer l'humidite du sol a partir du signal, ces methodes permettent aussi d'estimer l'epaisseur de sol representee par l'humidite ainsi estimee.

  16. 78 FR 37652 - Environmental Impact Statement: Kenosha, Racine, Milwaukee, Waukesha, Washington, Dodge, Fond Du...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-21

    ..., Waukesha, Washington, Dodge, Fond Du Lac, Winnebago, Outagamie and Brown Counties, Wisconsin AGENCY... proposed Interstate conversion of U.S. Highway 41 in Milwaukee, Waukesha, Washington, Dodge, Fond du Lac... 41 to an Interstate in Milwaukee, Waukesha, Washington, Dodge, Fond du Lac, Winnebago, Outagamie,...

  17. La chirurgie du diaphragme sous aortique

    PubMed Central

    Moutakiallah, Younes; Maaroufi, Ilham; Aithoussa, Mahdi; Bamous, Mehdi; Abdou, Abdessamad; Atmani, Noureddine; Hatim, Abdedaïm; Amahzoune, Brahim; Bekkali, Youssef El; Boulahya, Abdelatif

    2016-01-01

    Le diaphragme sous aortique se caractérise par une certaine latence clinique et une faible morbi-mortalité. La chirurgie reste le traitement de choix malgré un réel risque de récurrence à long terme. Nous rapportons 18 patients opérés entre Avril 1994 et Mars 2011 pour diaphragme sous aortique d’âge moyen de 18,1±9,7 ans avec 11 patients de sexe masculin. Le diaphragme était de nature fibreuse chez 13 patients et fibro-musculaire chez 5 patients. Tous les patients ont été opérés par résection de diaphragme associée à une myectomie, une plastie aortique, une fermeture de communication interventriculaire et une ligature de canal artériel perméable respectivement chez 3, 3, 2 et 2 patients. La Mortalité opératoire était nulle et sans aucun cas de trouble de conduction postopératoire. Le suivi a duré en moyenne 44,3±36,8 mois sans aucun décès tardif. Deux patients ont présenté une récidive de diaphragme qui a nécessité une réopération avec bonne évolution. La tendance actuelle dans la chirurgie du diaphragme se fait vers des interventions précoces et des résections plus extensives. Cependant, le risque de récidive impose une surveillance échographique systématique et rapprochée. PMID:27516830

  18. Les rivières et les sources de la Plaine du Cul-de-Sac: extrait du rapport sur les eaux souterraines de la Plaine du Cul-de-Sac

    USGS Publications Warehouse

    Taylor, George C., Jr.; Lemoine, Rémy C.

    1949-01-01

    Les principales rivières de la Plaine du Cul-de-Sac, la Rivière Grise ou Grande Rivière du Cul-de-Sac et la Rivière Blanche, prennent naissance sur le flanc Nord du Massif de la Selle à des altitudes de 1,300 à 1,800 mètres au dessus du niveau de la mer. Elles coulent à l’amont à travers des gorges profondes et sont éloignées de 9 Kms. dans la partie central de la bordure Sud de la plaine.

  19. Du pont ''Freon'' helps tap geothermal wells for power

    SciTech Connect

    Not Available

    1984-07-01

    Low-grade heat from geothermal wells can now be harnessed to produce electricity by using Du Pont ''Freon'' IF as the power conversion fluid. The new system was developed by Turbonetics Energy Inc. The company's Organic Rankine Cycle (ORC) system takes advantage of the low boiling point (117F) of Du Pont ''Freon'' TF. Geothermal energy is harnessed by utilizing the heat from 200F to 400F water to vaporize the ''Freon'' power fluid. Then the fluid expands through a turbine and drives a generator. The system can produce from 600 kW of electric power.

  20. Baisse du HDL-cholestérol indicateur du stress oxydatif dans le diabète de type 2

    PubMed Central

    Kabamba, Arsène Tshikongo; Bakari, Salvius Amuri; Longanga, Albert Otshudi; Lukumwena, Zet Kalala

    2014-01-01

    L'hypercholestérolémie est étroitement liée au stress oxydatif. Lorsqu'il y a trop de cholestérol qui circule dans le sang, il n'est pas utilisé en totalité par les cellules et il risque de s'accumuler dans les vaisseaux sanguins. Cela peut entrainer la formation des plaques d'athérosclérose qui gênent la circulation sanguine et provoquent des accidents cardiovasculaires. Le stress oxydatif apparait très tôt dans l'histoire des complications du diabète de type 2, et est lié à l'oxydation du glucose mais aussi à la peroxydation lipidique. Le cholestérol-HDL est un marqueur important du stress oxydatif par sa capacité à faciliter la métabolisation du cholestérol, sa baisse est souvent considérée comme la source de beaucoup d'inquiétudes. L'objectif est l’évaluation de la variation du taux de cholestérol-HDL, marqueur du stress oxydatif, chez les patients diabétiques de type 2 dans la population congolaise. Nous avons inclus dans cette étude prospective des cas témoins des patients diabétiques de type 2 reconnus et diagnostiqués, et des témoins non diabétiques appariés selon l’âge et le sexe. Parallèlement au bilan biologique classique, une analyse d'un des facteurs de risque du stress oxydatif a été réalisée: baisse de HDL-Cholestérol. L’âge moyen des 30 patients diabétiques (47,77±10,78 ans) était comparable à celui des 30 témoins (48,83±10,73 ans). Une baisse significative du cholestérol-HDL dans le sang était observée chez 100% des diabétiques et 50% des témoins (p=0,0000). L'augmentation du HDL cholestérol permet d’éliminer le mauvais cholestérol en excès en nettoyant les tissus et en ramenant le cholestérol vers le foie. Lors du diabète de type 2 on constate une baisse sanguine sensible du taux de HDL-cholestérol, qui est signe indicateur du stress oxydatif. PMID:25767660

  1. Non-exponential nature of calorimetric and other relaxations: Effects of 2 nm-size solutes, loss of translational diffusion, isomer specificity, and sample size

    NASA Astrophysics Data System (ADS)

    Johari, G. P.; Khouri, J.

    2013-03-01

    Certain distributions of relaxation times can be described in terms of a non-exponential response parameter, β, of value between 0 and 1. Both β and the relaxation time, τ0, of a material depend upon the probe used for studying its dynamics and the value of β is qualitatively related to the non-Arrhenius variation of viscosity and τ0. A solute adds to the diversity of an intermolecular environment and is therefore expected to reduce β, i.e., to increase the distribution and to change τ0. We argue that the calorimetric value βcal determined from the specific heat [Cp = T(dS/dT)p] data is a more appropriate measure of the distribution of relaxation times arising from configurational fluctuations than β determined from other properties, and report a study of βcal of two sets of binary mixtures, each containing a different molecule of ˜2 nm size. We find that βcal changes monotonically with the composition, i.e., solute molecules modify the nano-scale composition and may increase or decrease τ0, but do not always decrease βcal. (Plots of βcal against the composition do not show a minimum.) We also analyze the data from the literature, and find that (i) βcal of an orientationally disordered crystal is less than that of its liquid, (ii) βcal varies with the isomer's nature, and chiral centers in a molecule decrease βcal, and (iii) βcal decreases when a sample's thickness is decreased to the nm-scale. After examining the difference between βcal and β determined from other properties we discuss the consequences of our findings for theories of non-exponential response, and suggest that studies of βcal may be more revealing of structure-freezing than studies of the non-Arrhenius behavior. On the basis of previous reports that β → 1 for dielectric relaxation of liquids of centiPoise viscosity observed at GHz frequencies, we argue that its molecular mechanism is the same as that of the Johari-Goldstein (JG) relaxation. Its spectrum becomes broader on

  2. Complete thermodynamic characterization of the multiple protonation equilibria of the aminoglycoside antibiotic paromomycin: a calorimetric and natural abundance 15N NMR study.

    PubMed

    Barbieri, Christopher M; Pilch, Daniel S

    2006-02-15

    The binding of aminoglycoside antibiotics to a broad range of macromolecular targets is coupled to protonation of one or more of the amino groups that typify this class of drugs. Determining how and to what extent this linkage influences the energetics of the aminoglycoside-macromolecule binding reaction requires a detailed understanding of the thermodynamics associated with the protonation equilibria of the aminoglycoside amino groups. In recognition of this need, a calorimetric- and NMR-based approach for obtaining the requisite thermodynamic information is presented using paromomycin as the model aminoglycoside. Temperature- and pH-dependent 15N NMR studies provide pK(a) values for the five paromomycin amino groups, as well as the temperature dependence of these pK(a) values. These studies also indicate that the observed pK(a) values associated with the free base form of paromomycin are lower in magnitude than the corresponding values associated with the sulfate salt form of the drug. This difference in pK(a) is due to drug interactions with the sulfate counterions at the high drug concentrations (> or = 812 mM) used in the 15N NMR studies. Isothermal titration calorimetry studies conducted at drug concentrations < or = 45 microM reveal that the extent of paromomycin protonation linked to the binding of the drug to its pharmacologically relevant target, the 16 S rRNA A-site, is consistent with the pK(a) values of the free base and not the sulfate salt form of the drug. Temperature- and pH-dependent isothermal titration calorimetry studies yield exothermic enthalpy changes (deltaH) for protonation of the five paromomycin amino groups, as well as positive heat capacity changes (deltaC(p)) for three of the five amino groups. Regarded as a whole, the results presented here represent an important first step toward establishing a thermodynamic database that can be used to predict how aminoglycoside-macromolecule binding energetics will be influenced by conditions such

  3. Consequences experimentales des effets des fluctuations du vide sur la fluorescence parametrique et la generation du second harmonique en milieu confine

    NASA Astrophysics Data System (ADS)

    Robichaud, Luc

    Les fluctuations du vide, qui consistent en l'apparition momentanee de particules, ce qui est permit par le principe d'incertitude de Heisenberg, joue un role primordial dans les processus photoniques, en particulier les processus non-lineaires. Par la manipulation de ces fluctuations du vide a l'aide de confinement optique, on retrouve deux phenomenes particuliers : l'intensification de la fluorescence parametrique (Walker, 2008) et l'inhibition de la generation du second harmonique (Collette, 2013). Dans ce travail, on presente les resultats dans le cas classique ; c'est-a-dire sans fluctuations du vide et confinement. Par la suite, on presente les effets des fluctuations du vide et du confinement, ce qui mene aux deux effets mentionnes. Dans le cas de la fluorescence parametrique, le bruit quantique sur le champ interne et externe est calcule, le role du desaccord de phase dans le modele est expose et une generalisation tridimensionnelle est etudiee afin de generaliser la conception du modele d'un cas unidimensionnel a un cas tridimensionnel planaire. Dans le cas de la generation du second harmonique, les difficultes d'un modele purement tridimensionnel sont exposees et ensuite le cas limite planaire est etudie.

  4. Micro-machined calorimetric biosensors

    DOEpatents

    Doktycz, Mitchel J.; Britton, Jr., Charles L.; Smith, Stephen F.; Oden, Patrick I.; Bryan, William L.; Moore, James A.; Thundat, Thomas G.; Warmack, Robert J.

    2002-01-01

    A method and apparatus are provided for detecting and monitoring micro-volumetric enthalpic changes caused by molecular reactions. Micro-machining techniques are used to create very small thermally isolated masses incorporating temperature-sensitive circuitry. The thermally isolated masses are provided with a molecular layer or coating, and the temperature-sensitive circuitry provides an indication when the molecules of the coating are involved in an enthalpic reaction. The thermally isolated masses may be provided singly or in arrays and, in the latter case, the molecular coatings may differ to provide qualitative and/or quantitative assays of a substance.

  5. College of DuPage Student Portrait, Fall Quarter 1999.

    ERIC Educational Resources Information Center

    College of DuPage, Glen Ellyn, IL. Office of Research and Planning.

    The report profiles the College of DuPage's (COD) fall quarter 1999 student body. It presents a brief history of the college's enrollment and a comparison of enrollments with other Illinois community colleges. It also provides demographic information on current students. Additionally, enrollment information is included by program, division, and…

  6. W. E. B. Du Bois: Reform, Will, and the Veil

    ERIC Educational Resources Information Center

    England, Lynn; Warner, W. Keith

    2013-01-01

    While W. E. B. Du Bois is widely recognized for his contributions to the sociology of race, his contributions to the foundations of sociology are largely ignored. His sociology is based on African American reformism, a version of pragmatism, and a contingent historicism. The basic view of sociology is one that emphasizes the role of chance and…

  7. Pic-du-Midi Observatory (Observatoire Midi-Pyrenees) (OMP)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    OMP is under the administrative supervision of both the Institute des Sciences de l'Univers (INSU) of the French National Center for Scientific Research (CNRS) and the Ministry of Research, Technology and Education. It has laboratories located at the Université Paul Sabatier in Toulouse, Bagnères, Lannemezan and at the summit of Pic du Midi de Bigorre....

  8. Cost-Effective Remediation of Depleted Uranium (DU) at Environmental Restoration Sites

    SciTech Connect

    MILLER,MARK; GALLOWAY,ROBERT B.; VANDERPOEL,GLENN; JOHNSON,ED; COPLAND,JOHN; SALAZAR,MICHAEL

    1999-11-03

    Numerous sites in the United States and around the world are contaminated with depleted uranium (DU) in various forms. A prevalent form is fragmented DU originating from various scientific tests involving high explosives and DU during weapon-development programs, at firing practice ranges, or in war theaters where DU was used in armor-piercing projectiles. The contamination at these sites is typically very heterogeneous, with discrete, visually identifiable DU fragments mixed with native soil. The bulk-averaged DU activity is quite low, whereas DU fragments, which are distinct from the soil matrix, have much higher specific activity. DU is best known as a dark metal that is nearly twice as dense as lead, but DU in the environment readily weathers (oxidizes) to a distinctive bright yellow color that is quite visible. While the specific activity (amount of radioactivity per mass of soil) of DU is relatively low and presents only a minor radiological hazard, the fact that DU is radioactive and visually identifiable makes it desirable to remove the DU ''contamination'' from the environment. The typical approach to conducting this DU remediation is to use radiation-detection instruments to identify the contaminant and then to separate it from the adjacent soil, packaging it for disposal as radioactive waste. This process can be performed manually or by specialized, automated equipment. Alternatively, a more cost-effective approach might be simple mechanical or gravimetric separation of the DU fragments from the host soil matrix. At SNL/NM, both the automated and simple mechanical approaches have recently been employed. This paper discusses the pros/cons of the two approaches.

  9. Paralysie néonatal unilatérale du nerf radial

    PubMed Central

    Benemmane, Halima; Hali, Fouzia; Marnissi, Farida; Benchikhi, Hakima

    2015-01-01

    La paralysie néonatale unilatérale du nerf radial est rare, son diagnostic est essentiellement clinique, elle peut-être diagnostiquée à tort en tant que paralysie du plexus brachial. Nous rapportons un cas clinique. A l'examen clinique du nouveau-né; l'extension du poignet, du pouce et des articulations métacarpo-phalangiennes était impossible, alors qu'il y avait une conservation de la prono-supination et la flexion du poignet et des mouvements de l’épaule et du coude. Le diagnostic de la paralysie du plexus brachial était écarté cliniquement devant la mobilisation active de l’épaule et la flexion du coude. Notre patient a bénéficié de kinésithérapie pour éviter l'apparition d'attitudes vicieuses et d'amyotrophie. L'extension active du poignet était obtenue après deux mois. PMID:26587133

  10. Les inconvénients de perdre du poids

    PubMed Central

    Bosomworth, N. John

    2012-01-01

    Résumé Objectif Explorer les raisons pour lesquelles la perte de poids à long terme échoue la plupart du temps et évaluer les conséquences de diverses trajectoires pondérales, y compris la stabilité, la perte et le gain. Source des données Les études qui évaluent les paramètres pondéraux dans la population sont en majorité observationnelles. Des données probantes de niveau I ont été publiées pour évaluer l’influence des interventions relatives au poids sur la mortalité et la qualité de vie. Message principal Seulement un petit pourcentage des personnes qui désirent perdre du poids réussissent à le faire de manière durable. La mortalité est la plus faible chez les personnes se situant dans la catégorie de poids élevé-normal et surpoids. La trajectoire pondérale la plus sécuritaire est la stabilité du poids avec une optimisation de la condition physique et métabolique. Il est démontré que la mortalité est plus faible chez les personnes ayant des comorbidités reliées à l’obésité si elles perdent du poids. Il est aussi établi que la qualité de vie sur le plan de la santé est meilleure chez les personnes obèses qui perdent du poids. Par contre, la perte de poids chez une personne obèse autrement en santé est associée à une mortalité accrue. Conclusion La perte de poids est recommandable seulement chez les personnes qui ont des comorbidités reliées à l’obésité. Les personnes obèses en santé qui veulent perdre du poids devraient être informées qu’il peut y avoir des risques à le faire. Une stratégie qui se traduit par un indice de masse corporelle stable avec une condition physique et métabolique optimisée, peu importe le poids, est l’option d’intervention la plus sécuritaire en ce qui concerne le poids.

  11. Rupture simultanée du ligament croisé antérieur et du ligament patellaire: à propos d'un cas

    PubMed Central

    Achkoun, Abdessalam; Houjairi, Khalid; Quahtan, Omar; Hassoun, Jalal; Arssi, Mohamed; Rahmi, Mohamed; Garch, Abdelhak

    2016-01-01

    La rupture simultanée du tendon rotulien et du ligament croisé antérieur est une lésion relativement rare. Son diagnostic peut facilement manquer lors de l'examen initial. Les options de traitement incluent la réparation immédiate du tendon rotulien avec soit la reconstruction simultanée ou différée de ligament croisé antérieur. Nous rapportons le cas d'une rupture combinée du tendon rotulien et du ligament croisé antérieur chez un jeune footballeur de 22 ans. Une approche de traitement en deux temps a été effectuée avec un excellent résultat fonctionnel. PMID:27366288

  12. A Conversation with Lee Alvin DuBridge - Part I

    NASA Astrophysics Data System (ADS)

    Goodstein, Judith R.

    Physicist Lee A. DuBridge became president of the California Institute of Technology in 1946. In this interview he recalls the immediate problems he faced, including his dealings with Robert A. Millikan, whom he replaced as chief administrator of the institute; institute financing and inadequate salaries. DuBridge also talks about the advent of federal support for peacetime science and Millikan's distaste for it; his close working relationship with Robert F. Bacher, who came to the institute in 1949 as chairman of the Division of Physics, Mathematics, and Astronomy; his recollections of the meteorologist Irving P. Krick, the physicist Alexander Goetz, and the chemist Linus Pauling; and his attempts to build up the Humanities Division.

  13. Du Pont Classifications of 4 ASAS-SN Supernovae

    NASA Astrophysics Data System (ADS)

    Morrell, N.; Shappee, Benjamin J.

    2016-08-01

    We report optical spectroscopy (range 370-910 nm) of four supernovae discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN; Shappee et al. 2014, ApJ, 788, 48) using the du Pont 2.5-m telescope (+ WFCCD) at Las Campanas Observatory on July 31 and Aug. 01 2016 UT. We performed a cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J.

  14. Du Pont Classifications of 2 ASAS-SN Supernovae

    NASA Astrophysics Data System (ADS)

    Shappee, Benjamin J.; Prieto, J. L.; Rich, J.; Madore, B.; Poetrodjojo, Henry; D'Agostino, Joshua

    2016-09-01

    We report optical spectroscopy (range 370-910 nm) of two supernovae discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN; Shappee et al. 2014, ApJ, 788, 48) using the du Pont 2.5-m telescope (+ WFCCD) at Las Campanas Observatory on Aug. 30 and Sep. 1 2016 UT. We performed a cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J.

  15. Une forme exceptionnelle de la luxation perilunaire du carpe

    PubMed Central

    Elouakili, Issam; Ouchrif, Younes; Najib, Abdeljaouad; Ouakrim, Redouane; Lamrani, Omar; Kharmaz, Mohammed; Ismael, Farid; Lahlou, Abdo; Elouadghiri, Mohammed; El Bardouni, Ahmed; Mahfoud, Mustapha; Berrada, Mohammed Saleh; El Yaccoubi, Mouradh

    2014-01-01

    Les luxations périlunaires (LPL) du carpe sont des lésions extrêmement rares, qui peuvent passer inaperçue en raison d'un tableau clinique souvent trompeur, des radiographies en profil non strict ou d'interprétation difficile. Nous rapportons l'observation d'une luxation périlunaire stade III selon la classification de Witvoët et Allieu chez un patient de 32 ans, il s'agit d'une forme encore plus rare voire exceptionnelle et qui peut induire de sérieux problèmes en raison de la sévérité des dommages ligamentaires et du risque de nécrose du semilunaire plus important dans ce type de lésions. Le traitement est toujours chirurgical et doit être réalisé dans les plus brefs délais afin d’éviter les complications. PMID:25404968

  16. Low-temperature heat capacity of diopside glass (CaMgSi2O6): A calorimetric test of the configurational-entropy theory applied to the viscosity of liquid silicates

    USGS Publications Warehouse

    Richet, P.; Robie, R.A.; Hemingway, B.S.

    1986-01-01

    Heat-capacity measurements have been made between 8 and 370 K on an annealed and a rapidly quenched diopside glass. Between 15 and 200 K, Cp does not depend significantly on the thermal history of the glass. Below 15 K Cp is larger for the quenched than for the annealed specimen. The opposite is true above 200 K as a result of what is interpreted as a secondary relaxation around room temperature. The magnitude of these effects, however, is small enough that the relative entropies S(298)-S(0) of the glasses differ by only 0.5 J/mol K, i.e., a figure within the combined experimental uncertainties. The insensitivity of relative entropies to thermal history supports the assumption that the configurational heat capacity of the liquid may be taken as the heat capacity difference between the liquid and the glass (??Cp). Furthermore, this insensitivity allows calculation of the residual entropies at 0 K of diopside glasses as a function of the fictive temperature from the entropy of fusion of diopside and the heat capacities of the crystalline, glassy and liquid phases. For a glass with a fictive temperature of 1005 K, for example, this calorimetric residual entropy is 24.3 ?? 3 J/mol K, in agreement with the prediction made by RICHET (1984) from an analysis of the viscosity data with the configurational-entropy theory of relaxation processes of Adam and Gibbs (1965). In turn, all the viscosity measurements for liquid diopside, which span the range 0.5-4?? 1013 poise, can be quantitatively reproduced through this theory with the calorimetrically determined entropies and ??Cp data. Finally, the unclear significance of "activation energies" for structural interpretations of viscosity data is emphasized, and the importance of ??Cp and glass-transition temperature systematics for determining the composition and temperature dependences of the viscosity is pointed out. ?? 1986.

  17. Annuaire du bureau des Longitudes : guide de données astronomiques 2011 pour l'observation du ciel

    NASA Astrophysics Data System (ADS)

    Institut de Mécanique Céleste Et de Calcul Des Ephémérides (Imcce); Bureau Des Longitudes (Bdl)

    2010-07-01

    Destiné aux astronomes, professionnels ou amateurs, cet ouvrage se décompose de la façon suivante : Les trois premiers chapitres de cet ouvrage contiennent : les données sur les différents calendriers et leur concordance, les fêtes légales en France, les différentes échelles de temps, les dates de décrets sur les heures légales en France métropolitaine parues au Journal Officiel depuis 1916 ; des notions nécessaires à la compréhension et à l'emploi des éphémérides contenues dans l'ouvrage. Les chapitres suivant fournissent des éphémérides astronomiques : les positions du Soleil et de la Lune ; les positions des planètes et de leurs satellites ; les positions des astéroïdes et des comètes ; les explications et des données pour l'observation de la surface du Soleil, de la Lune et des planètes ; des cartes du ciel, une liste de constellations et les positions et occultations des étoiles ; des données sur les éclipses de Soleil et de Lune et sur les phénomènes astronomiques ; la liste des observatoires astronomiques les plus connus.

  18. Annuaire du bureau des Longitudes : guide de données astronomiques 2012 pour l'observation du ciel

    NASA Astrophysics Data System (ADS)

    Institut de Mécanique Céleste Et de Calcul Des Ephémérides (Imcce); Bureau Des Longitudes (Bdl)

    2011-07-01

    Destiné aux astronomes, professionnels ou amateurs, cet ouvrage se décompose de la façon suivante : Les trois premiers chapitres de cet ouvrage contiennent : les données sur les différents calendriers et leur concordance, les fêtes légales en France, les différentes échelles de temps, les dates de décrets sur les heures légales en France métropolitaine parues au Journal Officiel depuis 1916 ; des notions nécessaires à la compréhension et à l'emploi des éphémérides contenues dans l'ouvrage. Les chapitres suivant fournissent des éphémérides astronomiques : les positions du Soleil et de la Lune ; les positions des planètes et de leurs satellites ; les positions des astéroïdes et des comètes ; les explications et des données pour l'observation de la surface du Soleil, de la Lune et des planètes ; des cartes du ciel, une liste de constellations et les positions et occultations des étoiles ; des données sur les éclipses de Soleil et de Lune et sur les phénomènes astronomiques ; la liste des observatoires astronomiques les plus connus.

  19. Association between Fatigue and Autistic Symptoms in Children with Cri du Chat Syndrome

    ERIC Educational Resources Information Center

    Claro, Anthony; Cornish, Kim; Gruber, Reut

    2011-01-01

    In the current study, the authors examined whether the fatigue level of children diagnosed with cri du chat syndrome was associated with the expression of autistic symptoms. Sixty-nine children with cri du chat syndrome were compared with 47 children with moderate to severe intellectual disabilities who did not differ on intellectual severity.…

  20. Luxation de l’épaule compliquée de paralysie du plexus brachial

    PubMed Central

    Lukulunga, Loubet Unyendje; Moussa, Abdou Kadri; Mahfoud, Mustapha; EL Bardouni, Ahmed; Berrada, Mohamed Saleh; El Yaacoubi, Moradh

    2014-01-01

    Les auteurs rapportent l'observation d'une paralysie totale du plexus brachial survenue trois mois après un épisode de luxation antéro-interne sous coracoïdienne associée à une fracture du trochiter chez une patiente âgée de 88 ans. PMID:25426187

  1. Lambeaux autofermants pour le traitement des brulures electriques du scalp par haut voltage

    PubMed Central

    Hafidi, J.; El Mazouz, S.; El Mejatti, H.; Fejjal, N.; Gharib, N.E.; Abbassi, A.; Belmahi, A.M.

    2011-01-01

    Summary Les brûlures électriques par haut voltage sont responsables de gros dégâts tissulaires en immédiat et dans les jours suivant l’accident du fait de la chaleur importante dégagée par effet joule et de la thrombose microvasculaire évolutive. Les pertes de substances du scalp secondaires à ces brûlures nécessitent une couverture par lambeaux vu la destruction du périoste et du calvarium en regard. De juin 1997 à juin 2008, 15 patients ont été traités pour des pertes de substance du scalp secondaires à des brûlures électriques par haut voltage de diamètre allant de 8 à 11 cm et siégeant dans la région tonsurale. Ces patients ont été opérés dans la première semaine suivant l’accident. Les pertes de substance du scalp de taille moyenne secondaires à ces brûlures peuvent être couvertes per primam de façon fiable par des lambeaux locaux axialisés et multiples. Nous relatons l’expérience du Service de Chirurgie Plastique du Centre Hospitalier Universitaire Ibn-Sina, Rabat, Maroc, dans la gestion et la prise en charge de ces brûlures. PMID:22262963

  2. Prevalence of Autism Spectrum Phenomenology in Cornelia de Lange and Cri du Chat Syndromes

    ERIC Educational Resources Information Center

    Moss, Joanna F.; Oliver, Chris; Berg, Katy; Kaur, Gurmeash; Jephcott, Lesley; Cornish, Kim

    2008-01-01

    Autism spectrum disorder characteristics have not been evaluated in Cornelia de Lange and Cri du Chat syndromes using robust assessments. The Autism Diagnostic Observation Schedule and Social Communication Questionnaire were administered to 34 participants with Cornelia de Lange syndrome and a comparison group of 23 participants with Cri du Chat…

  3. Non-destructive analysis of DU content in the NIF hohlraums

    SciTech Connect

    Gharibyan, Narek; Moody, Ken J.; Shaughnessy, Dawn A.

    2015-12-16

    The advantage of using depleted uranium (DU) hohlraums in high-yield deuterium-tritium (DT) shots at the National Ignition Facility (NIF) is addressed by Döppner, et al., in great detail [1]. This DU based hohlraum incorporates a thin layer of DU, ~7 μm thick, on the inner surface along with a thin layer of a gold coating, ~0.7 μm thick, while the outer layer is ~22 μm thick gold. A thickness measurement of the DU layer can be performed using an optical microscope where the total DU weight can be computed provided a uniform DU layer. However, the uniformity of the thickness is not constant throughout the hohlraum since CAD drawing calculations of the DU weight do not agree with the computed values from optical measurements [2]. Therefore, a non-destructive method for quantifying the DU content in hohlraums has been established by utilizing gamma-ray spectroscopy. The details of this method, along with results from several hohlraums, are presented in this report.

  4. Dysfonctionnements radio-induits du transport colique chez le rat

    NASA Astrophysics Data System (ADS)

    François, A.; Lebrun, F.; Ksas, B.; Aigueperse, J.; Gourmelon, P.; MacNaughton, W. K.; Griffiths, N. M.

    1998-04-01

    The symptom commonly associated with whole body irradiation is diarrhoea, a still quite obscure phenomenon, which leads to decreased chance of cure of irradiated people. The aim of this study was to provide evidence for dysfunction of intestinal water and electrolyte transport regulation by the enteric nervous system after exposure to ionising radiation. This study shows decreased capacity of enteric nervous system to influence colonic transport 3days after irradiation, correlated to a diminished response to a neurotransmitter: serotonin. Radio-induced diarrhea may result from epithelial structural injury but also from impaired regulatory processes of intestinal transport. L'un des symptômes majeurs d'une irradiation corporelle totale ou abdominale est l'apparition de diarrhées, dont les causes sont encore mal connues, et qui mettent en jeu le pronostique vital de l'individu irradié. Cette étude vise à mettre en évidence l'atteinte de la régulation du transport intestinal d'eau et d'électrolytes par les rayonnements ionisants. On observe une diminution de la capacité du système nerveux entérique à influencer le transport colique 3jours après irradiation, corrélée à une diminution de la réponse épithéliale à un neurotransmetteur : la sérotonine. Les diarrhées radio-induites résulteraient d'une atteinte structurelle de l'épithélium mais également des processus de régulation du transport intestinal.

  5. Automation of Pic du Midi 2-m Telescope Bernard Lyot

    NASA Astrophysics Data System (ADS)

    Lavie-Cambot, Jean-Marie; Lacassagne, F.; Ambert, P.; Arrotis, J.-M.; Argentin, Y.; Arberet, M.-P.; Chereau, E.; Decha, C.; Delaigue, C.; Guesdon, L.; Laurent-Burguiere, D.; Malbreil, G.

    2011-03-01

    Since 2007, Pic du Midi 2-m Telescope Bernard Lyot is dedicated to spectropolarimetry with a scientific niche in stella magnetism. In parallel, TBL is progressively evolving from an analogic human-controlled telescope, to a fully automated computer controlled digital telescope. This evolution required TBL team to replace all electronics and motors with digital system (parvex, brushless motors, buscan) components, and to integrate the dataflow system from proposal to archiving into a fully coordinates, remote-access software suite. A trained technician can already control remotely the telescope, instrument and science programs from anywhere. Further robotisation will require a high-level expert system to be defined.

  6. Portage vaginal du streptocoque du groupe B chez la femme enceinte au niveau de la région de Marrakech

    PubMed Central

    Bassir, Ahlam; Dhibou, Hanane; Farah, Majdi; Mohamed, Lharmis; Amal, Addebous; Nabila, Souraa; Abderahim, Aboulfalah; Asmouki, Hamid; Soummani, Abderraouf

    2016-01-01

    Introduction Le streptocoque du groupe B est le principal agent impliqué dans les infections materno-fœtales, les septicémies et les méningites du nouveau-né à terme. L'objectif est de déterminer le taux de portage maternel du streptocoque du groupe B (SGB) à terme. Méthodes Un prélèvement vaginal a été réalisé de manière prospective chez 275 parturientes lors de l'entrée en salle d'accouchement sur une période de 06 mois. Résultats Le taux de portage était de 20,2%. Le portage était variable en fonction de l’âge gestationnel, il constitue 57.5% entre 37 et 38 semaines d'aménorrhée. Aucun des facteurs de risque n'a était statistiquement prédictif du portage maternel du SGB. Conclusion Le dépistage doit être réalisé à partir de 37 semaines d'aménorrhée, et comme le portage est intermittent, un prélèvement négatif ne garantirait pas que le portage soit négatif à l'accouchement. PMID:27222693

  7. Les astronomes de l'Empire du Milieu

    NASA Astrophysics Data System (ADS)

    Bonnet-Bidaud, J. M.

    2007-02-01

    Explosions d'étoiles, comètes, durée du jour, taches solaires, dans tous ces domaines, des observations chinoises datant de plusieurs siècles sont encore utilisées aujourd'hui. Pendant plus de 4000 ans, les astronomes de l'Empire du Milieu, organisés dans les grands observatoires impériaux, ont noté jour après jour, mois après mois, avec la plus grande précision tous les phénomènes célestes. Et ce sont des milliers de textes couvrant des périodes depuis au moins le Ve siècle avant l'ère moderne jusqu'à fin de la dernière dynastie des Qing en 1911, qui ont été conservés et dont une grande partie n'a pu encore être véritablement étudiée. Un véritable trésor, malheureusement très mal connu en Europe et, de façon incompréhensible, largement ignoré par l'histoire moderne des sciences.

  8. Anévrysme ventriculaire gauche et communication interventriculaire compliquant un infarctus du myocarde

    PubMed Central

    Belkhadir, Mohammed; MoutakiAllah, Younes; Raissouni, Zainab; Abdou, Abdessamad; Bamous, Mehdi; Nya, Fouad; Atmani, Noureddine; Houssa, Mahdi Ait; El Bekkali, Youssef; Boulahya, Abdellatif

    2014-01-01

    L'association d'une communication interventriculaire post infarctus du myocarde et d'un anévrysme du ventricule gauche chez un même patient est extrêmement rare et survient habituellement durant la première semaine qui suit un infarctus du myocarde. Nous rapportons le cas insolite d'un patient âgé de 63 ans, admis pour choc cardiogénique en rapport avec une communication inter ventriculaire apicale et un anévrysme ventriculaire gauche causés par un infarctus du myocarde antérieur. La correction chirurgicale a consisté en une fermeture du défect septal par un patch en dacron via une ventriculotomie gauche associée à une anévrysectomie et un mono pontage coronaire. Cette observation illustre d'une part la rareté de l'association communication inter ventriculaire-anévrysme ventriculaire gauche post infarctus du myocarde, et d'autre part l'efficacité du traitement chirurgical qui reste la seule option salvatrice pour cette pathologie. PMID:25328617

  9. Carcinome colloïde du sein: à propos d'un cas

    PubMed Central

    Laabadi, Kamilia; Jayi, Sofia; Alaoui, Fatimazohra Fdili; Bouguern, Hakima; Chaara, Hikmat; Melhouf, My Abdelilah

    2013-01-01

    Nous rapportons le cas d'une tumeur colloïde du sein chez un homme. Cette situation rare interpelle par son mode de découverte. Nous avons pris en charge un homme de 60 ans atteint d'une lésion rétro-aréolaire droite classée cliniquement T4b N1 M0 et suspecte radiologiquement. L'analyse histologique (microbiopsie) a conclu à un carcinome colloïde muqueux associé à une petite composante canalaire classique de grade I de SBR du sein. Les traitements complémentaires associent mastectomie, curage, chimiothérapie, radiothérapie et hormonothérapie. Le cancer du sein est rare chez l'homme. Le carcinome colloïde est exceptionnel puisqu'il représente seulement 1 à 6% de l'ensemble des cancers du sein. Il est encore plus rare chez l'homme. Ces tumeurs touchent une population spécifique et ont un meilleur pronostic que les autres types prépondérant dans les cancers du sein chez l'homme. A travers cette observation et une revue de la littérature, nous essaierons de discuter les principales caractéristiques anatomo-cliniques et évolutives de cette forme rare du cancer du sein. PMID:24772222

  10. A systematic review of the oral and craniofacial manifestations of cri du chat syndrome.

    PubMed

    Corcuera-Flores, José-Ramón; Casttellanos-Cosano, Lizett; Torres-Lagares, Daniel; Serrera-Figallo, María Ángeles; Rodríguez-Caballero, Ángela; Machuca-Portillo, Guillermo

    2016-07-01

    Cri du chat syndrome is an autosomal disorder. Because it affects few people in the population it is considered a rare disease, yet it is one of the most common autosomal chromosomal syndromes in humans. It entails pathognomonic alterations that affect the craniofacial and oral anatomy of patients. The aim of this study is to review these craniofacial and oral abnormalities in patients with Cri du chat syndrome. The PubMed Medline database was searched using two different strategies. First, we used "Dentistry" and "Cri du chat" as keywords; second, we used "Cri du chat" and "craniofacial." Seven articles in which the main orofacial and cranio-skeletal characteristics of patients with Cri du chat syndrome were described were selected according to the inclusion and exclusion criteria. Cri du Chat syndrome entails pathognomonic characteristics in the craniofacial area (epicanthus, short philtrum, and wide nasal bridge), the oral area (mandibular retrognathism and anterior open bite) and the cranial region (alterations at the cranial base angle and a small upper airway). However, more studies on larger samples are needed to specify the orofacial and craniofacial characteristics of patients with Cri du chat syndrome more accurately. Clin. Anat. 29:555-560, 2016. © 2015 Wiley Periodicals, Inc. PMID:26457586

  11. Le syndrome de Cri du Chat : A propos d’une observation

    PubMed Central

    Ouldim, Karim; Samri, Imane; Bouguenouch, Laila; Hamdaoui, Hasna; Otmani, Ihsan El; Hbibi, Mohamed; Chaouki, Sana; Hida, Moustapha

    2012-01-01

    Le syndrome du Cri du Chat (Cri du Chat syndrome, CdCS) est une anomalie chromosomique résultant d’une délétion de taille variable de l’extrémité du bras court du chromosome 5 (5p), incluant une région critique située en p15.2. Il représente une des délétions chromosomiques les plus fréquentes, son incidence dans la population générale est de 1/20 000 à 1/50 000. Les caractéristiques cliniques comprennent un cri monochromatique aigu, une microcéphalie, une dysmorphie cranio-faciale caractéristique évoluant avec l’âge et un retard mental et psychomoteur important. La taille de la délétion est variable, Le traitement est fonction des différents symptômes. Un remaniement chromosomique parental est retrouvé dans 12% des cas et la majorité des délétions responsables de la maladie du cri-du-chat surviennent de novo. Nous présentons une observation d’un syndrome du Cri du Chat, confirmé par caryotype métaphasique (46,XY,del(5)(p13) de novo). A travers cette observation nous mettrons à jour, les actualités scientifiques de ce rare syndrome, ainsi que la place des explorations cytogénétiques dans le diagnostic précis et le conseil génétique des syndromes dysmorphiques. PMID:22368747

  12. Le traumatisme du colon: l'expérience du CHU Hassan II de Fès

    PubMed Central

    Benjelloun, El Bachir; Hafid, Hasnai; Karim, Ibnmajdoub; Ousadden, Abdelmalek; Mazaz, Khalid; Taleb, Kahlid Ait

    2012-01-01

    Introduction Les traumatismes du colon sont associés à un risque majeur de complications septiques et de mortalité. Le but de notre étude est d’évaluer les circonstances, la prise en charge, le suivi et les facteurs pronostic de morbidité postopératoire des malades victimes d'un traumatisme colique. Méthodes Il s'agit d'une étude rétrospective sur une série de 49 patients opérés pour des plaies coliques aux services de chirurgie viscérale du CHU HASSAN II de Fès sur une période de 8 ans de juillet 2003 à juillet 2011. Résultats L’âge moyen de nos patients était de 25ans (16-70) avec une nette prédominance masculine (93.8%). Les plaies coliques secondaires à un traumatisme par arme blanche représentent 85% des cas (42 patients), suivi par les plaies iatrogènes au cours d'une coloscopie chez 6 patients (13%), puis les contusions abdominales chez 1 patient (2%). Les parties du cadre colique les plus touchées étaient le colon transverse chez 19 patients (38%) et le colon descendant chez 12 patients (24, 5%). Le colon sigmoïde était le segment le plus touché au cours d'une coloscopie4/6. Quarante-deux patients (85%) ont eu une suture primaire des plaies coliques, six patients (13%) une diversion fécale et un patient (2%) une résection-anastomose. Deux patients (4%) sont décédés suite à un choc septique. La morbidité globale était de 38,7% dominé essentiellement par l'infection de la paroi chez 14 patients et une péritonite post opératoire chez 3 patients. L'analyse univarié a montré une différence significatif en terme d'infection de la paroi entre le groupe colostomie versus suture simple (50% vs 20,9% p<0,05). L'atteinte du colon gauche et la réalisation d'une colostomie sont associés à un risque plus élevés de complications postopératoires. Conclusion La suture primaire peut être effectuée avec un faible taux de complications postopératoire chez la majorité des patients suite à un traumatisme du colon. PMID

  13. Solution NMR and calorimetric analysis of Rem2 binding to the Ca2+ channel β4 subunit: a low affinity interaction is required for inhibition of Cav2.1 Ca2+ currents.

    PubMed

    Xu, Xingfu; Zhang, Fangxiong; Zamponi, Gerald W; Horne, William A

    2015-05-01

    Rem, Rad, Kir/Gem (RGK) proteins, including Rem2, mediate profound inhibition of high-voltage activated Ca(2+) channels containing intracellular regulatory β subunits. All RGK proteins bind to voltage-gated Ca(2+) channel β subunit (Cavβ) subunits in vitro, but the necessity of the interaction for current inhibition remains controversial. This study applies NMR and calorimetric techniques to map the binding site for Rem2 on human Cavβ4a and measure its binding affinity. Our experiments revealed 2 binding surfaces on the β4 guanylate kinase domain contributing to a 156 ± 18 µM Kd interaction: a hydrophobic pocket lined by 4 critical residues (L173, N261, H262, and V303), mutation of any of which completely disrupted binding, and a nearby surface containing 3 residues (D206, L209, and D258) that when individually mutated decreased affinity. Voltage-gated Ca(2+) channel α1A subunit (Cav2.1) Ca(2+) currents were completely inhibited by Rem2 when co-expressed with wild-type Cavβ4a, but were unaffected by Rem2 when coexpressed with a Cavβ4a site 1 (L173A/V303A) or site 2 (D258A) mutant. These results provide direct evidence for a low-affinity Rem2/Cavβ4 interaction and show definitively that the interaction is required for Cav2.1 inhibition. PMID:25563298

  14. Localisation inhabituelle de la tuberculose: ostéoarthrite tuberculose du pouce

    PubMed Central

    Mortaji, Aziz; Koulali, Khalid; Galuia, Farid

    2014-01-01

    L'ostéoarthrite tuberculose est rare au niveau des doigts. Nous rapportons une observation d'atteinte du pouce chez un patient de 55 ans. Il avait présenté une tuméfaction douloureuse du pouce droit suite à un traumatisme du pouce. L’étude bactériologique et une biopsie avaient permis de confirmer le diagnostic. Un traitement antibacillaire de 12 mois avait donné des résultats satisfaisants. Les particularités de la prise en charge sont discutées par rapport aux données de la littérature. PMID:25932075

  15. DuPont/HFM Forum on carpet in health care facilities. Third in a series.

    PubMed

    1994-01-01

    DuPont and Health Facilities Management magazine invited 20 national experts to Dalton, GA--the carpet-manufacturing capital of the world--last year to take part in DuPont's first-ever Forum on Carpet in Health Care Facilities. During the two-hour roundtable discussion, moderated by DuPont's C. Jack Murph and HFM's Michael Hemmes, end-users, interior designers and carpet mill representative talked about the aesthetic, economic and performance aspects of using carpet in health care settings. Here's an edited version of what they said. PMID:10184014

  16. DuPont/HFM Forum on carpet in health care facilities. Roundtable discussion.

    PubMed

    Murph, J; Hemmes, M; Blyth, P L; Plappert, K K; Noell, E; VanStavern, V; Cama, R; Lynn, V; Pollitt, B S; Rainey, P M

    1993-11-01

    DuPont and Health Facilities Management magazine invited 20 national experts to Dalton, GA--the carpet-manufacturing capital of the world--on May 13 to take part in DuPont's first-ever Forum on Carpet in Health Care Facilities. During the two-hour roundtable discussion, moderated by DuPont's C. Jack Murph and HFM's Michael Hemmes, end-users, interior designers and mill representatives talked about the aesthetic, economic and performance aspects of using carpet in health care settings. Here's an edited version of what they said. PMID:10183973

  17. Etude theorique du jet de plasma supersonique a courant continu

    NASA Astrophysics Data System (ADS)

    Jodoin, Bertrand

    La déposition par plasma supersonique à courant continu permet d'obtenir une qualité de dépôt supérieure au jet subsonique. Un modèle numérique a été développé dans le but de mieux comprendre les mécanismes de transfert à l'intérieur de la tuyère et d'estimer l'influence des paramètres d'opération de la torche sur le jet à la sortie de la tuyère. Les équations d'Euler, auxquelles sont ajoutées l'effet Joule, la conduction et les pertes par rayonnement sont résolues à l'aide de la méthode de Jameson. Un schéma centré est utilisé pour résoudre les champs électriques. La sous-couche cathodique en déséquilibre thermodynamique est modélisée à l'aide du modèle simple de Morrow et Lowke. Quelques détails sur les aspects numériques facilitant la convergence du système sont donnés. Le modèle est validé pour un écoulement compressible classique et pour un jet de plasma supersonique à l'aide de résultats de la littérature. Les champs à l'intérieur de la tuyère sont analysés afin de déterminer l'influence de l'hydrogène, de l'intensité du courant et de la géométrie de la tuyère sur les caractéristiques de l'écoulement.

  18. Polymorphisme de l'apolipoprotéine E dans la population du nord du Maroc: fréquence et influence sur les paramètres lipidiques

    PubMed Central

    Benyahya, Fatiha; Barakat, Amina; Ghailani, Naima; Bennani, Mohcine

    2013-01-01

    Introduction L'objectif de ce travail est de déterminer les fréquences alléliques et génotypiques des sites polymorphes situés dans le gène de l'apolipoprotéine E (apo E) ainsi que leur impact sur les paramètres cliniques et lipidiques dans un échantillon de la population du nord du Maroc cliniquement diagnostiqué ADH. Méthodes Le génotype de l'apo E a été analysé par séquençage direct chez 46 patients cliniquement diagnostiqués ADH selon les critères standards. Résultats Les fréquences des allèles epsilon 3, epsilon 2 et epsilon 4 ont été respectivement 78.3%, 2.2% et 19.6%. La fréquence de l'allèle epsilon 4 est très élevée chez la population du nord du Maroc en comparaison avec les populations des autres régions marocaines. Elle est similaire à celle rapportée dans les pays de l'Europe du nord. Les taux du cholestérol total, du cholestérol LDL ainsi que la présence des xanthomes et les maladies cardiovasculaires ne différent pas entre les génotypes de l'apoE. En revanche, les résultats ont montré une influence de l'allèle epsilon4 sur le taux des triglycérides chez les sujets obèses. Conclusion Le génotype de l'apoE ne peut expliquer le phénotype clinique et biochimique présenté par des patients du Nord du Maroc cliniquement diagnostiqués ADH. PMID:24396563

  19. Cirque du Monde en tant qu’intervention en santé

    PubMed Central

    Fournier, Cynthia; Drouin, Mélodie-Anne; Marcoux, Jérémie; Garel, Patricia; Bochud, Emmanuel; Théberge, Julie; Aubertin, Patrice; Favreau, Gil; Fleet, Richard

    2014-01-01

    Résumé Objectif Présenter le programme Cirque du Monde du Cirque du Soleil et son potentiel en tant qu’intervention en soins de santé de première ligne pour les médecins de famille. Sources des données Une revue de la littérature menée dans les bases de données PubMed, Cochrane Library, PsycINFO, La Presse, Eureka, Google Scholar et Érudit à l’aide des mots-clés circus, social circus, Cirque du Monde et Cirque du Soleil. Une initiative à Montréal nommée Espace Transition qui s’inspire directement de Cirque du Monde. Communication personnelle avec le conseiller principal en formation en cirque social du Cirque du Soleil. Sélection d’études Les 50 premiers articles ou sites Internet répertoriés pour chaque mot-clé dans chacune des bases de données ciblées ont été révisés sur la base des titres et des résumés, s’il s’agissait d’un article, ou sur la base du titre et du contenu de la page, s’il s’agissait d’une page Internet. Ensuite, les articles et les sites Internet qui étudiaient un aspect du cirque social ou qui présentaient une intervention impliquant le cirque étaient retenus pour une révision. Aucune contrainte d’année de publication n’a été appliquée étant donné qu’on cherchait une littérature générale sur le cirque social. Synthèse Aucun article n’a été trouvé sur le cirque social en tant qu’intervention en santé. Nous avons trouvé une étude sur l’utilisation du cirque en tant qu’intervention en milieu scolaire. Cette étude a démontré une augmentation de l’estime personnelle des enfants grâce à l’intervention. Nous avons trouvé une étude sur l’utilisation du cirque en tant qu’intervention sur une réserve amérindienne. Cette étude présente des résultats qualitatifs non spécifiques au programme du cirque social. Les autres articles répertoriés n’étaient que des descriptions du cirque social. Un site web concernant l’utilisation du cirque social pour

  20. Proprietes ionochromes et photochromes de derives du polythiophene

    NASA Astrophysics Data System (ADS)

    Levesque, Isabelle

    La synthese et la caracterisation de derives regioreguliers du polythiophene ont ete effectuees en solution et sur des films minces. La spectroscopie UV-visible de ces derives a permis de constater qu'ils peuvent posseder des proprietes chromiques particulieres selon le stimulus auquel ils sont soumis. Par exemple, une augmentation de la temperature permet en effet aux polymeres de passer d'une couleur violette a jaune, et ce, a l'etat solide aussi bien qu'en solution. Ces proprietes chromiques semblent regies par une transition conformationnelle (plane a non-plane) de la chaine principale. Ce travail avait pour but de mieux comprendre l'influence de l'organisation des chaines laterales sur les transitions chromiques. Deux derives synthetises possedant des chaines laterales sensibles aux cations alcalins se sont averes etre ionochromes en plus d'etre thermochromes. Il s'agit d'un polymere comportant des chaines laterales de type oligo(oxyethylene) et d'un autre comportant un groupement ether couronne specifique aux ions lithium. Les effets chromiques observes sont expliques par des interactions non-covalentes des cations avec les atomes d'oxygene des chaines laterales dans le cas du premier polymere, et par l'insertion de l'ion Li + dans la cavite de l'ether couronne dans le cas du second polymere. Ces interactions semblent provoquer une diminution de l'organisation induisant ainsi une torsion de la chaine principale. Les deux polymeres semblent specifiques a certains cations et pourraient donc servir comme detecteurs optiques. La specificite aux ions Li+ du second polymere pourrait aussi permettre la conduction ionique, en plus de la conductivite electronique caracteristique des polythiophenes, ce qui pourrait s'averer utile dans le cas de batteries legeres entierement faites de polymeres et de sels de lithium. D'autres derives comportant des chaines laterales de type azobenzene se sont averes etre photochromes en plus d'etre thermochromes. Le groupement lateral a

  1. Restauration fonctionnelle du rachis : effet du niveau initial de douleur sur les performances des sujets lombalgiques chroniques

    PubMed Central

    Caby, Isabelle; Olivier, N; Mendelek, F; Kheir, R Bou; Vanvelcenaher, J; Pelayo, P

    2014-01-01

    HISTORIQUE : La lombalgie chronique est une douleur lombaire persistante d’origine multifactorielle. Le niveau de douleur initial reste faiblement utilisé pour analyser et comparer les réponses des patients lombalgiques au programme de reconditionnement. OBJECTIFS : Apprécier et évaluer les réponses des sujets lombalgiques chroniques très douloureux à une prise en charge dynamique et intensive. MÉTHODOLOGIE : 144 sujets atteints de lombalgie chronique ont été inclus dans un programme de restauration fonctionnelle du rachis de 5 semaines. Les sujets ont été classés en deux groupes de niveau de douleur: un groupe atteint de douleur sévère (n = 28) et un groupe atteint de douleur légère à modérée (n = 106). L’ensemble des sujets ont bénéficié d’une prise en charge identique comprenant principalement de la kinésithérapie, de l’ergothérapie, du reconditionnement musculaire et cardio-vasculaire ainsi qu’un suivi psychologique. Les paramètres physiques (flexibilité, force musculaire) et psychologiques (qualité de vie) ont été mesurés avant (T0) et après le programme (T5sem). RÉSULTATS : L’ensemble des performances physiques et fonctionnelles des sujets très douloureux sont moins bonnes et le retentissement de la lombalgie sur la qualité de vie, pour ces mêmes sujets, est majoré à T0. Toutes les différences significatives constatées à T0 entre les deux groupes s’effacent à T5sem. CONCLUSIONS : Les sujets lombalgiques chroniques très douloureux répondent favorablement au programme dynamique et intensif. L’intensité douloureuse de la lombalgie n’aurait pas d’effet sur les réponses au programme. La restauration fonctionnelle du rachis apporterait aux sujets la possibilité de mieux gérer leur douleur quel que soit son niveau. PMID:25299476

  2. Une angiocholite secondaire à un thrombus tumoral d'une tumeur neuroendocrine primitive du foie

    PubMed Central

    Baba, Hicham; Allaoui, Mohamed; Elfahssi, Mohammed; Bounaim, Ahmed; Ali, Abdelmounaim Ait; Oukabli, Mohamed; Sair, Khalid; Zentar, Aziz

    2015-01-01

    Nous rapportons le cas exceptionnel d'une patiente de 54 ans prise en charge pour une angiocholite due à un thrombus tumoral, d'une tumeur neuroendocrine primitive (TNE Ive) du foie, dans la voie biliaire principale. PMID:26966504

  3. Lymphome malin non hodgkinien du cavum: protocoles thérapeutiques et facteurs pronostiques

    PubMed Central

    Ouraini, Saloua; Nakkabi, Ismail; Benariba, Fouad

    2015-01-01

    Le lymphome malin non hodgkinien est une entité histologique rare parmi les cancers du cavum, la plupart des tumeurs du nasopharynx étant des carcinomes indifférenciés ou Undifferencied Carcinoma of Nasopharyngeal Type (UCNT); Il pose souvent un problème de diagnostic positif clinique et histologique. La symptomatologie est généralement peu spécifique et la démarche étiologique repose sur la biopsie du cavum faite à l'examen endoscopique avec examen immuno-histochimique. Nous rapportons le cas d'un lymphome non hodgkinien avec atteinte du nasopharynx, l'analyse anatomopathologique est en faveur d'un lymphome malin non hodgkinien de phénotype B. Les aspects cliniques, radiologiques, histologiques et thérapeutiques sont décrits. PMID:26889334

  4. Water-quality along selected flowpaths in the Prairie du Chien-Jordan aquifer, southeastern Minnesota

    SciTech Connect

    Smith, S.E. )

    1994-04-01

    The Prairie du Chien-Jordan aquifer in southeastern Minnesota is comprised of the dolomitic Prairie du Chien Group and the underlying Jordan Sandstone. Differences in water quality between the Prairie du Chien and the Jordan parts of the aquifer were investigated by sampling 139 wells in six study areas within Hennepin, Dakota, and Olmsted Counties. The study areas, which represent paths of groundwater flow through the aquifer, averaged 13 miles long and 3 miles wide. The wells were screened in the Jordan, Prairie du Chien, and overlying aquifers. Concentrations of tritium, nitrite plus nitrate nitrogen, and chloride were useful indicators of the actual and potential extent of human-related contamination of the aquifer. Differences in water quality were related to land use, aquifer permeability, thickness and lithology of overlying units, presence of confining units, flow path length, and well construction. Water samples from wells completed in the Jordan aquifer have lower tritium, nitrite plus nitrate nitrogen, and chloride concentrations than samples from wells completed in the overlying Prairie du Chien, St. Peter, and glacial drift aquifers. The distribution of these indicators on vertical sections of the aquifer, geochemical analysis of saturation indices (WATEQF), piper diagrams, and statistical analyses were used to analyze the hydrogeology and sensitivity to contamination of the Prairie du Chien-Jordan aquifer.

  5. A yeast artificial chromosome contig of the critical region for cri-du-chat syndrome

    SciTech Connect

    Goodart, S.A.; Rojas, K.; Overhauser, J.

    1994-11-01

    Cri-du-chat is a chromosomal deletion syndrome characterized by partial deletion of the short arm of chromosome 5. The clinical symptoms include growth and mental retardation, microcephaly, hypertelorism, epicanthal folds, hyptonia, and a high-pitched monochromatic cry that is usually considered diagnostic for the syndrome. Recently, a correlation between clinical features and the extent of the chromosome 5 deletions has identified two regions of the short arm that appear to be critical for the abnormal development manifested in this syndrome. Loss of a small region in 5p15.2 correlates with all of the clinical features of cri-du-chat with the exception of the cat-like cry, which maps to 5p15.3. Here the authors report the construction of a YAC contig that spans the chromosomal region in 5p15.2 that plays a major role in the etiology of the cri-du-chat syndrome. YACs that span the 2-Mb cri-du-chat critical region have been identified and characterized. This YAC contig lays the groundwork for the construction of a transcriptional map of this region and the eventual identification of genes involved in the clinical features associated with the cri-du-chat syndrome. It also provides a new diagnostic tool for cri-du-chat in the shape of a YAC clone that may span the entire critical region. 24 refs., 4 figs., 2 tabs.

  6. Prise en charge des traumatismes graves du rein

    PubMed Central

    Lakmichi, Mohamed Amine; Jarir, Redouane; Sadiki, Bader; Zehraoui; Bentani; Wakrim, Bader; Dahami, Zakaria; Moudouni; Sarf, Ismail

    2015-01-01

    Les traumatismes graves du rein de grade III, IV et V selon la classification de l'Amercan Society for Surgery For Trauma (ASST) sont plus rares et se retrouvent dans 5% des cas en moyenne. Leur prise en charge est souvent délicate, nécessitant alors des centres expérimentés dotés de moyen adéquats d'imagerie (scanner spiralé). Cependant, durant ces dernières années, la prise en charge de ces traumatismes a évolué vers une attitude de moins en moins chirurgicale grâce à l’évolution des techniques de la radiologie interventionnelle, de l'endourologie et des moyens de surveillance aux urgences et de réanimation. L'objectif de cette étude est d’évaluer notre expérience dans la prise en charge des traumatismes rénaux de haut grade. Notre étude rétrospective porte sur 25 cas de traumatismes grave du rein de grade III, IV et V selon la classification de l'ASST, colligés entre Janvier 2002 et Juin 2009 au service d'urologie du centre Hospitalier Universitaire Mohammed VI, Université Cadi Ayyad de Marrakech, Maroc. Nous avons étudié les données épidémiologiques, les signes cliniques et biologiques à l'admission (état de choc hémorragique, taux d'hémoglobine), les données radiologiques (échographie et scanner), les lésions associées, la prise en charge thérapeutique et les complications. L’âge moyen de nos patients était de 24,9 ans 15 et 58 ans, avec une prédominance masculine (sex-ratio = 7, 3). Le rein droit était intéressé dans 15 cas (60%). Le traumatisme rénal était fermé dans 15 cas, et ouvert par arme blanche dans 10 cas. Huit patients se sont présentés en état de choc hémorragique (32%). Une anémie inférieur à 10g /100ml a été observée dans 10 cas (40%). L'uroscanner fait systématiquement à l'admission a retrouvé un grade III (10 cas), grade IV (13 cas) et grade V (2 cas). La prise en charge a consisté en une exploration chirurgicale avec néphrectomie chez 2 cas de Grade IV pour une instabilité h

  7. Characterizing the secondary hydration shell on hydrated myoglobin, hemoglobin, and lysozyme powders by its vitrification behavior on cooling and its calorimetric glass-->liquid transition and crystallization behavior on reheating.

    PubMed Central

    Sartor, G; Hallbrucker, A; Mayer, E

    1995-01-01

    For hydrated metmyoglobin, methemoglobin, and lysozyme powders, the freezable water fraction of between approximately 0.3-0.4 g water/g protein up to approximately 0.7-0.8 g water/g protein has been fully vitrified by cooling at rates up to approximately 1500 K min-1 and the influence of cooling rate characterized by x-ray diffractograms. This vitreous but freezable water fraction started to crystallize at approximately 210 K to cubic ice and at approximately 240 K to hexagonal ice. Measurements by differential scanning calorimetry have shown that this vitreous but freezable water fraction undergoes, on reheating at a rate of 30 K min-1, a glass-->liquid transition with an onset temperature of between approximately 164 and approximately 174 K, with a width of between approximately 9 and approximately 16 degrees and an increase in heat capacity of between approximately 20 and approximately 40 J K-1 (mol of freezable water)-1 but that the glass transition disappears upon crystallization of the freezable water. These calorimetric features are similar to those of water imbibed in the pores of a synthetic hydrogel but very different from those of glassy bulk water. The difference to glassy bulk water's properties is attributed to hydrophilic interaction and H-bonding of the macromolecules' segments with the freezable water fraction, which thereby becomes dynamically modified. Abrupt increase in minimal or critical cooling rate necessary for complete vitrification is observed at approximately 0.7-0.8 g water/g protein, which is attributed to an abrupt increase of water's mobility, and it is remarkably close to the threshold value of water's mobility on a hydrated protein reported by Kimmich et al. (1990, Biophys. J. 58:1183). The hydration level of approximately 0.7-0.8 g water/g protein is approximately that necessary for completing the secondary hydration shell. PMID:8599674

  8. Berberine-induced anticancer activities in FaDu head and neck squamous cell carcinoma cells.

    PubMed

    Seo, Yo-Seob; Yim, Min-Ji; Kim, Bok-Hee; Kang, Kyung-Rok; Lee, Sook-Young; Oh, Ji-Su; You, Jae-Seek; Kim, Su-Gwan; Yu, Sang-Joun; Lee, Gyeong-Je; Kim, Do Kyung; Kim, Chun Sung; Kim, Jin-Soo; Kim, Jae-Sung

    2015-12-01

    In the present study, we investigated berberine‑induced apoptosis and the signaling pathways underlying its activity in FaDu head and neck squamous cell carcinoma cells. Berberine did not affect the viability of primary human normal oral keratinocytes. In contrast, the cytotoxicity of berberine was significantly increased in FaDu cells stimulated with berberine for 24 h. Furthermore, berberine increased nuclear condensation and apoptosis rates in FaDu cells than those in untreated control cells. Berberine also induced the upregulation of apoptotic ligands, such as FasL and TNF-related apoptosis-inducing ligand, and triggered the activation of caspase-8, -7 and -3, and poly(ADP ribose) polymerase, characteristic of death receptor-dependent extrinsic apoptosis. Moreover, berberine activated the mitochondria‑dependent apoptotic signaling pathway by upregulating pro-apoptotic factors, such as Bax, Bad, Apaf-1, and the active form of caspase-9, and downregulating anti-apoptotic factors, such as Bcl-2 and Bcl-xL. In addition, berberine increased the expression of the tumor suppressor p53 in FaDu cells. The pan-caspase inhibitor Z-VAD-fmk suppressed the activation of caspase-3 and prevented cytotoxicity in FaDu cells treated with berberine. Interestingly, berberine suppressed cell migration through downregulation of vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-2, and MMP-9. Moreover, the phosphorylation of extracellular signal-regulated kinase (ERK1/2) and p38, components of the mitogen-activated protein kinase pathway that are associated with the expression of MMP and VEGF, was suppressed in FaDu cells treated with berberine for 24 h. Therefore, these data suggested that berberine exerted anticancer effects in FaDu cells through induction of apoptosis and suppression of migration. Berberine may have potential applications as a chemotherapeutic agent for the management of head and neck squamous carcinoma. PMID:26503508

  9. Resistivity tomography of Pointe du Hoc cliffs for stability assessment

    NASA Astrophysics Data System (ADS)

    Udphuay, S.; Everett, M. E.; Warden, R.

    2008-12-01

    Pointe du Hoc WWII battlefield overlooking the English Channel in western Normandy, France, is an important cultural resource, being an integral component of the June 6 1944 D-Day invasion. Two major buildings, the forward observation post (OP) and Col. Rudder's command post (RCP), are now perched perilously close to the cliff's edge owing to six decades of cliff retreat. Geophysical surveys were carried out in March 2008 to investigate the risk of cliff failure and to inform possible geotechnical remediation strategies with a final goal toward re-opening the observation post that is now closed to visitors. The geophysical surveying is accomplished by high-resolution resistivity tomography, conducted in extreme topography and in the midst of dense cultural clutter. The results of the OP tomography indicate that the highest mass movement hazard is associated with the marine caverns at the base of the cliff at the point of strongest wave attack. These caverns occupy the future site of a sea arch which will threaten the OP building. There is a high probability of a soil wedge failure on the east facing cliff edge close to the OP building. Such a failure could damage or destroy the building. The possibility of a sudden catastrophic failure along any one of these fractures cannot be ruled out. The greatest risk at the RCP site, which is under less immediate threat, is associated with soil wedge failures at the top of the cliffs.

  10. Identification d'une loi thermo-élasto-viscoplastique en vue de la modélisation du laminage à chaud du cuivre

    NASA Astrophysics Data System (ADS)

    Moureaux, P.; Moto Mpong, S.; Remy, M.; Bouffioux, C.; Lecomte-Beckers, J.; Habraken, A. M.

    2002-12-01

    la mise au point d'un modèle de simulation de la dernière passe du laminage à chaud du cuivre ne présente à priori pas de problème du point de vue numérique pour un code d'éléments finis non linéaire. La collecte d'informations précises tant sur le procédé industriel que sur le comportement du matériau est par contre une opération non triviale. Cet article présente les diverses méthodes expérimentales mises en œuvre pour caractériser le matériau : essais de compression à chaud, mesures d'analyse thermique différentielle, essais de dilatométrie et de diffusivité. Les méthodes permettant d'identifier les paramètres de la loi élasto-visco-plastique de type Norton-Hoff à partir des essais sont présentées et une analyse bibliographique investigue le problème de la détermination du module de Young à haute température. Tant les hypothèses supplémentaires relatives au procédé et nécessaires au modèle que les résultats finaux sont résumés.

  11. Modelisation frequentielle de la permittivite du beton pour le controle non destructif par georadar

    NASA Astrophysics Data System (ADS)

    Bourdi, Taoufik

    Le georadar (Ground Penetrating Radar (GPR)) constitue une technique de controle non destructif (CND) interessante pour la mesure des epaisseurs des dalles de beton et la caracterisation des fractures, en raison de ses caracteristiques de resolution et de profondeur de penetration. Les equipements georadar sont de plus en plus faciles a utiliser et les logiciels d'interpretation sont en train de devenir plus aisement accessibles. Cependant, il est ressorti dans plusieurs conferences et ateliers sur l'application du georadar en genie civil qu'il fallait poursuivre les recherches, en particulier sur la modelisation et les techniques de mesure des proprietes electriques du beton. En obtenant de meilleures informations sur les proprietes electriques du beton aux frequences du georadar, l'instrumentation et les techniques d'interpretation pourraient etre perfectionnees plus efficacement. Le modele de Jonscher est un modele qui a montre son efficacite dans le domaine geophysique. Pour la premiere fois, son utilisation dans le domaine genie civil est presentee. Dans un premier temps, nous avons valide l'application du modele de Jonscher pour la caracterisation de la permittivite dielectrique du beton. Les resultats ont montre clairement que ce modele est capable de reproduire fidelement la variation de la permittivite de differents types de beton sur la bande de frequence georadar (100 MHz-2 GHz). Dans un deuxieme temps, nous avons montre l'interet du modele de Jonscher en le comparant a d'autres modeles (Debye et Debye-etendu) deja utilises dans le domaine genie civil. Nous avons montre aussi comment le modele de Jonscher peut presenter une aide a la prediction de l'efficacite de blindage et a l'interpretation des ondes de la technique GPR. Il a ete determine que le modele de Jonscher permet de donner une bonne presentation de la variation de la permittivite du beton dans la gamme de frequence georadar consideree. De plus, cette modelisation est valable pour differents

  12. A Description of Adaptive and Maladaptive Behaviour in Children and Adolescents with Cri-du-Chat Syndrome

    ERIC Educational Resources Information Center

    Teixeira, M. C. T. V.; Emerich, D. R.; Orsati, F. T.; Rimerio, R. C.; Gatto, K. R.; Chappaz, I. O.; Kim, C. A.

    2011-01-01

    Background: Psychological tests can be useful to record adaptive and maladaptive behaviours of children with intellectual disability. The objective of this study was to describe the adaptive and maladaptive behaviour of children and adolescents with Cri-du-chat syndrome. Methods: The sample consisted of 10 children and adolescents with Cri-du-chat…

  13. Graphs as a Managerial Tool: A Case Study of Du Pont's Use of Graphs in the Early Twentieth Century.

    ERIC Educational Resources Information Center

    Yates, JoAnne

    1985-01-01

    Sketches the development of business graphs in America. Examines their early use at Du Pont and the origin of the chart room around 1920, an important factor in the executive control systems at Du Pont. Draws lessons from this case study for managers and teachers of business communication. (PD)

  14. La genèse du concept de champ quantique

    NASA Astrophysics Data System (ADS)

    Darrigol, O.

    This is a historical study of the roots of a concept which has proved to be essential in modern particle physics : the concept of quantum field. The first steps were accomplished by two young theoreticians : Pascual Jordan quantized the free electromagnetic field in 1925 by means of the formal rules of the just discovered matrix mechanics, and Paul Dirac quantized the whole system charges + field in 1927. Using Dirac's equation for electrons (1928) and Jordan's idea of quantized matter waves (second quantization), Werner Heisenberg and Wolfgang Pauli provided in 1929-1930 an extension of Dirac's radiation theory and the proof of its relativistic invariance. Meanwhile Enrico Fermi discovered independently a more elegant and pedagogical formulation. To appreciate the degree of historical necessity of the quantization of fields, and the value of contemporaneous critics to this approach, it was necessary to investigate some of the history of the old radiation theory. We present the various arguments however provisional or naïve or wrong they could be in retrospect. So we hope to contribute to a more vivid picture of notions which, once deprived of their historical setting, might seem abstruse to the modern user. Nous présentons une étude historique des origines d'un concept devenu essentiel dans la physique moderne des particules : le concept de champ quantique. Deux jeunes théoriciens franchirent les premières étapes : Pascual Jordan quantifia le champ électromagnétique en 1925 grâce aux règles formelles de la mécanique des matrices naissante, et Paul Dirac quantifia le système complet charges + champ en 1927. Au moyen de l'équation de l'électron de Dirac (1928) et de l'idée de Jordan d'ondes de matière quantifiées (deuxième quantification), Werner Heisenberg et Wolfgang Pauli donnèrent en 1929-1930 une extension de la théorie du rayonnement de Dirac et la preuve de son invariance relativiste. Pendant ce temps Enrico Fermi découvrit ind

  15. Pc2-mediated SUMOylation of WWOX is essential for its suppression of DU145 prostate tumorigenesis.

    PubMed

    Choi, Hye-Jin; Park, Jung-Hwan; Park, Jong-Hwan; Lee, Kyung Bok; Oh, Sang-Muk

    2015-12-21

    Tumor suppressor WW domain-containing oxidoreductase (WWOX) is depleted in various cancer types. Here we report that WWOX is modified by small ubiquitin-like modifier (SUMO) proteins and represses DU145 prostate cancer tumorigenesis in a SUMOylation-dependent manner. Ectopic WWOX was shown to associate with SUMO2/3 or E2 Ubc9. Furthermore, we revealed that WWOX SUMOylation was promoted by E3 ligase polycomb2 (Pc2), and that WWOX associated with Pc2. Meanwhile, anisomycin-induced activator protein-1 (AP-1) activity was markedly diminished by co-expression of SUMO and WWOX. Also, WWOX wild type (WT), but not WWOX SUMO mutant (K176A) markedly reduced both DU145 prostate cancer cell proliferation and xenograft tumorigenesis. Collectively, our findings demonstrate that SUMO modification of WWOX is essential for its suppressive activity for DU145 prostate cancer tumorigenesis. PMID:26592150

  16. Purification, identification and preliminary crystallographic studies of Pru du amandin, an allergenic protein from Prunus dulcis

    SciTech Connect

    Gaur, Vineet; Sethi, Dhruv K.; Salunke, Dinakar M.

    2008-01-01

    The purification, identification, crystallization and preliminary crystallographic studies of an allergy-related protein, Pru du amandin, from P. dulcis nuts are reported. Food allergies appear to be one of the foremost causes of hypersensitivity reactions. Nut allergies account for most food allergies and are often permanent. The 360 kDa hexameric protein Pru du amandin, a known allergen, was purified from almonds (Prunus dulcis) by ammonium sulfate fractionation and ion-exchange chromatography. The protein was identified by a BLAST homology search against the nonredundant sequence database. Pru du amandin belongs to the 11S legumin family of seed storage proteins characterized by the presence of a cupin motif. Crystals were obtained by the hanging-drop vapour-diffusion method. The crystals belong to space group P4{sub 1} (or P4{sub 3}), with unit-cell parameters a = b = 150.7, c = 164.9 Å.

  17. Contribution de l'altimetrie satellitaire a l'etude de la variabilite du niveau d'eau du Delta interieur du fleuve Niger

    NASA Astrophysics Data System (ADS)

    Telly Diepkile, Adama

    measurements were then corrected to bring them in the same altimetry reference level as Topex/Poseidon, thereby producing time series of 17 years (1992-2009). Following this analysis, we proposed a waveform retracking algorithm that integrates the backscattering coefficient to the time scale of penetration of the radar pulse in a medium with a presence of vegetation. The idea here is to consider the heterogeneity of a medium such as the Delta, which can be covered with vegetation. For this, we introduce into the equation of the waveform, the backscattering coefficient estimated from the so called water cloud model, to create a new algorithm called retracking algorithm of water cloud. This algorithm was applied to the Envisat and OSTM/Jason-2 data. The results of the algorithm were validated with in situ measurements of the Direction Nationale de l'Hydraulique du Mali and also with measurements acquired during a campaign of data collection conducted between August and October 2009. The observed differences are generally small (<+/- 1 m). The retracking algorithm of water cloud was compared to other existing algorithms. It shows a strong correlation with Ice-1 (R 2 = 0,84). Finally, we analyzed the influence of precipitation on the variations of the altimetry-derived water levels. Three sources of precipitations from satellite measurements and reanalysis data were considered in three catchments (basin Fouta Djallon in upstream, Bani basin and the inner basin in Mali). The analysis reveals the importance of precipitations, particularly in the basin of Fouta Djallon. Approximately 70% of sites analyzed in the Delta show a relatively strong correlation (R2 > 0,40) with the cumulative precipitations in the basins considered. Keywords : Remote Sensing, Satellite altimetry, Continental waters, Water level, Long term analysis, Inner Delta of Niger River, Water-cloud model, Envisat, Topex/Poseidon.

  18. Coronagraphy at Pic du Midi: Present state and future projects

    NASA Astrophysics Data System (ADS)

    Koechlin, L.

    2012-12-01

    The Pic du Midi coronagraph (CLIMSO) is a group of four instruments in parallel, taking images of the whole solar photosphere and low corona. It provides series of 2048*2048 pixels images taken nominally at 1 minute time intervals, all year long, weather permitting. A team of ≃q 60 persons, by groups of 2 or 3 each week, operate the instruments. Their work is programmed in collaboration with Institut de Recherches en astrophysique et planétologie (IRAP) of Observatoire Midi Pyrénées (OMP), and with Programme National Soleil Terre (PNST). The four instruments of CLIMSO (L1, C1, L2 and C2) collect images of the Sun as following: 1) L1 : photosphere in H-α (656.28 nm) ; 2) L2 : photosphere in Ca-II (393.37 nm) ; 3) C1 : prominences in H-α ; 4) C2 : prominences in He-I (1083.0 nm). The data taken are stored in fits format images and mpeg films. They are available publicly on data bases such as BASS 2000 Meudon ({http://bass2000.obspm.fr/home.php?lang=en} and BASS2000 Tarbes ({http://bass2000.bagn.obs-mip.fr/base/sun/index.php}). Several solar studies are carried in relation with these data. In addition to the raw fits images, new images will soon be sent to the data bases: they will be calibrated in solar surface emittance, expressed in W/m^2/nm/steradian. Series of mpeg films for each day are presented in superposed color layers, so as to visualize the multispectral information better. New instrumental developments are planned for the next years and already financed. They will use spectropolarimetry to measure the magnetic field and radial velocities in the photosphere and corona. The data will cover the entire solar disc and have a sample rate of one map per minute.

  19. Evaluation du niveau de connaissance des patients sur la gestion du traitement par les antis vitamines K dans le service de cardiologie de Ouagadougou

    PubMed Central

    Samadoulougou, André; Temoua Naibe, Dangwé; Mandi, Germain; Yameogo, Relwendé Aristide; Kabore, Elisé; Millogo, Georges; Yameogo, Nobila Valentin; Kologo, Jonas Koudougou; Thiam/Tall, Anna; Toguyeni, Boubacar Jean Yves; Zabsonre, Patrice

    2014-01-01

    Introduction Les antivitamines K (AVK), traitement anticoagulant oral le plus largement prescrit, posent un réel problème de santé publique du fait de leur risque iatrogène. L'objectif de cette étude était de préciser le niveau de connaissance des patients sur la gestion de leur traitement par les AVK. Méthodes Il s'est agi d'une enquête transversale descriptive réalisée au CHU-Yalgado Ouédraogo, sur une période de 03 mois : du 1er mars au 31 mai 2012. Un questionnaire a été administré aux patients bénéficiant d'un traitement AVK depuis au moins un mois. Résultats Soixante-dix patients ont été inclus dans l'étude dont 30 hommes. L'âge moyen était de 49 ans ± 16 ans. Les cardiopathies et la maladie thromboembolique veineuse justifiant l'institution du traitement AVK étaient retrouvées respectivement dans 58,6% et 41,4% des cas. Le nom de l'AVK et la raison exacte du traitement étaient connus respectivement dans 91,4% et 67,1% des cas. Plus de la moitié des patients (68,6%) savaient que les AVK rendaient le sang plus fluide. Quarante-six patients (65,7%) citaient l'INR comme examen biologique de surveillance du traitement et seulement 28 patients (40%) connaissaient les valeurs cibles. La majorité des patients ne connaissait pas les risques encourus en cas de surdosage (72,8%) et de sous-dosage (71,4%). Une automédication par anti-inflammatoire non stéroïdien était signalée par 18 patients (25,7%). Les choux (74,3%) et la laitue (62,9%), aliments à consommer avec modération, étaient les plus cités. Conclusion Les connaissances des patients sur la gestion des AVK étaient fragmentaires et insuffisantes pour assurer la sécurité et l'efficacité du traitement. La création d'un programme d'éducation thérapeutique sur les AVK s'avère alors nécessaire. PMID:25870741

  20. In vitro and in vivo antimycobacterial activities of a new quinolone, DU-6859a.

    PubMed Central

    Saito, H; Tomioka, H; Sato, K; Dekio, S

    1994-01-01

    A new fluoroquinolone, DU-6859a, was studied for its in vitro and in vivo antimycobacterial activities. MIC determination by the agar dilution method with 7H11 medium revealed that DU-6859a had MICs at which 90% of M. kansasii (0.78 microgram/ml), M. marinum (1.56 micrograms/ml), M. scrofulaceum (1.56 micrograms/ml), M. fortuitum (0.39 microgram/ml), M. chelonae subsp. abscessus (6.25 micrograms/ml), and M. chelonae subsp. chelonae (1.56 micrograms/ml) were inhibited were 4 to 32 times lower than those of ofloxacin and sparfloxacin. The MICs of DU-6859a at which 90% of M. tuberculosis (0.2 microgram/ml) and M. avium-M. intracellulare complex (12.5 micrograms/ml each) were inhibited were comparable to those of sparfloxacin but were four- to eightfold lower than those of ofloxacin. Thus, DU-6859a possessed more potent in vitro activity than sparfloxacin and ofloxacin against most mycobacterial species. DU-6859a exerted significant efficacy against infections caused by M. intracellulare and M. chelonae subsp. abscessus induced in mice when it was given at a dose of 1 mg per mouse (ca. 50 mg/kg of body weight) in terms of reducing the frequency of occurrence and the degree of gross pulmonary or renal lesions and bacterial loads in the lungs, spleens, or kidneys. The efficacy of DU-6859a was greater than that of ofloxacin and was more pronounced against M. chelonae infections than against M. intracellulare infections. PMID:7695276

  1. Long-term corrosion and leaching of depleted uranium (DU) in soil.

    PubMed

    Schimmack, W; Gerstmann, U; Schultz, W; Geipel, G

    2007-08-01

    Corrosion and leaching of depleted uranium (DU) was investigated for 3 years using six DU munitions (145-264 g DU) each buried in a column with a soil core of about 3.3 kg dry soil mass. The columns were installed in an air-conditioned laboratory. Each week they were irrigated and (238)U was determined in the effluents by inductively coupled plasma mass spectrometry. In addition, (235)U was measured occasionally to assure that the (238)U was predominantly from the DU munition. On average, 14.5 g corresponding to 7.9% of the initial DU mass was corroded after 3 years, indicating an increased corrosion as compared to the first year of observation. The leaching rates increased much stronger than the corrosion rates by factors of more than 100, resulting in a mean total amount of leached (238)U of 13 mg as compared to 0.03 mg after the first year. Uranium species identified in the seepage water by time-resolved laser-induced fluorescence spectroscopy were mainly hydroxo and carbonate compounds, while those in the corroded material were phosphate compounds. It is concluded that the dramatic increase of the leaching and its large temporal variability do not allow any extrapolation for the future. However, the high (238)U concentrations observed in the seepage water highlight the need for further investigations on the transport of (238)U through soil, in particular with regard to the potential future (238)U contamination of groundwater in areas affected by DU weapons. PMID:17549506

  2. Docetaxel induces Bcl-2- and pro-apoptotic caspase-independent death of human prostate cancer DU145 cells

    PubMed Central

    OGURA, TAKEHARU; TANAKA, YOSHIYUKI; TAMAKI, HIROKI; HARADA, MAMORU

    2016-01-01

    Docetaxel is a useful chemotherapeutic agent for the first-line treatment of hormone-refractory prostate cancer. Abnormal expression of Bcl-2 is commonly found in cancer cells, which increases their anti-apoptotic potency and chemo-resistance. We investigated the effects of Bcl-2 expression status on the susceptibility of DU145 cells, an androgen-independent human prostate cancer cell line, to docetaxel and other anticancer agents. A panel of Bcl-2-expressing DU145 cell lines was established. Bcl-2 expression levels were unrelated to the susceptibility of DU145 cells to docetaxel. The sensitivity of DU145 cells to cisplatin fluctuated, and the sensitivity to tumor necrosis factor (TNF)-α was decreased by Bcl-2 overexpression. In a xenograft mouse model, overexpression of Bcl-2 drastically decreased the sensitivity of DU145 cells to cisplatin and TNF-α; however, there was no change in the response to docetaxel. Fluorescent microscopy revealed that Bcl-2-overexpression had no effect on the docetaxel-induced death of DU145 cells, but significantly decreased DU145 cell death induced by cisplatin or TNF-α. Interestingly, docetaxel hardly induced caspase-3/7 activation in control or Bcl-2-overexpressing DU145 cells, but did at a low level in LNCaP cells, another prostate cancer cell line. Moreover, in contrast to LNCaP cells, the reduced viabilities of docetaxel-treated control and Bcl-2-overexpressing DU145 cells were not restored by the addition of either a Bid inhibitor or a panel of pro-apoptotic caspase inhibitors. These findings indicate that the antitumor effects of docetaxel on DU145 cells are independent of both Bcl-2 and pro-apoptotic caspases. PMID:27082738

  3. Docetaxel induces Bcl-2- and pro-apoptotic caspase-independent death of human prostate cancer DU145 cells.

    PubMed

    Ogura, Takeharu; Tanaka, Yoshiyuki; Tamaki, Hiroki; Harada, Mamoru

    2016-06-01

    Docetaxel is a useful chemotherapeutic agent for the first-line treatment of hormone-refractory prostate cancer. Abnormal expression of Bcl-2 is commonly found in cancer cells, which increases their anti-apoptotic potency and chemoresistance. We investigated the effects of Bcl-2 expression status on the susceptibility of DU145 cells, an androgen-independent human prostate cancer cell line, to docetaxel and other anticancer agents. A panel of Bcl-2-expressing DU145 cell lines was established. Bcl-2 expression levels were unrelated to the susceptibility of DU145 cells to docetaxel. The sensitivity of DU145 cells to cisplatin fluctuated, and the sensitivity to tumor necrosis factor (TNF)-α was decreased by Bcl-2 overexpression. In a xenograft mouse model, overexpression of Bcl-2 drastically decreased the sensitivity of DU145 cells to cisplatin and TNF-α; however, there was no change in the response to docetaxel. Fluorescent microscopy revealed that Bcl-2-overexpression had no effect on the docetaxel-induced death of DU145 cells, but significantly decreased DU145 cell death induced by cisplatin or TNF-α. Interestingly, docetaxel hardly induced caspase-3/7 activation in control or Bcl-2-overexpressing DU145 cells, but did at a low level in LNCaP cells, another prostate cancer cell line. Moreover, in contrast to LNCaP cells, the reduced viabilities of docetaxel-treated control and Bcl-2-overexpressing DU145 cells were not restored by the addition of either a Bid inhibitor or a panel of pro-apoptotic caspase inhibitors. These findings indicate that the antitumor effects of docetaxel on DU145 cells are independent of both Bcl-2 and pro-apoptotic caspases. PMID:27082738

  4. DuPont/HFM forum on carpet in health care facilities.

    PubMed

    1994-02-01

    DuPont and Health Facilities Management magazine invited 20 national experts to Dalton, GA--the carpet-manufacturing capital of the world--last year to take part in Dupont's first-ever Forum on Carpet in Health Care Facilities. During the two-hour roundtable discussion, moderated by DuPont's C. Jack Murph and HFM's Michael Hemmes, ender-users, interior designers and carpet mill representatives talked about the aesthetic, economic and performance aspects of using carpet in health care settings. Here's an edited version of what they said. PMID:10131499

  5. Dépistage précoce des retards du développement moteur

    PubMed Central

    Harris, Susan R.

    2016-01-01

    Résumé Objectif Décrire le test HINT (Harris Infant Neuromotor Test), un test d’évaluation du développement neuromoteur chez les nourrissons publié en 2010, qui s’appuie sur les normes canadiennes et peut être utilisé pour dépister les retards du développement moteur durant la première année de la vie. Qualité des données D’abondantes recherches ont été publiées sur la fiabilité intra-évaluateur, inter-évaluateur et test-retest ainsi que sur la validité convergente, prédictive, du contenu et des groupes connus du test HINT, de même que sur la sensibilité, la spécificité et les valeurs prédictives négatives et positives des inquiétudes des parents, telles qu’évaluées par le test HINT. La plupart des données probantes sont de niveau II. Message principal Il est important de diagnostiquer les retards du développement moteur durant la première année de vie, car ils sont souvent le signe de retards du développement généralisés ou de déficiences précises, telles que la paralysie cérébrale. Les inquiétudes des parents quant au développement moteur de leur enfant sont une valeur prédictive robuste de diagnostics subséquents de retard du développement moteur. Conclusion Seul le dépistage précoce des retards du développement moteur, initialement par l’entremise d’outils de dépistage comme le test HINT, permet de recommander le patient à une intervention précoce qui profiterait tant à l’enfant qu’à sa famille. PMID:27521405

  6. PHOTOMETRIC ANALYSIS OF HS Aqr, EG Cep, VW LMi, AND DU Boo

    SciTech Connect

    Djurasevic, G.; Latkovic, O.; Bastuerk, Oe.; Y Latin-Small-Letter-Dotless-I lmaz, M.; Cal Latin-Small-Letter-Dotless-I skan, S.; Senavc Latin-Small-Letter-Dotless-I , H. V.; K Latin-Small-Letter-Dotless-I l Latin-Small-Letter-Dotless-I coglu, T.; Ekmekci, F.; Tanr Latin-Small-Letter-Dotless-I verdi, T.

    2013-03-15

    We analyze new multicolor light curves for four close late-type binaries: HS Aqr, EG Cep, VW LMi, and DU Boo, in order to determine the orbital and physical parameters of the systems and estimate the distances. The analysis is done using the modeling code of G. Djurasevic, and is based on up-to-date measurements of spectroscopic elements. All four systems have complex, asymmetric light curves that we model by including bright or dark spots on one or both components. Our findings indicate that HS Aqr and EG Cep are in semi-detached, while VW LMi and DU Boo are in overcontact configurations.

  7. Intubation Difficile Chez le Brule de la Face et du Cou a la Phase de Sequelles

    PubMed Central

    Siah, S.; El Wali, A.; Ababou, K.; Nassim Sabah, T.; Drissi, N.K.; Ihrai, I.

    2006-01-01

    Summary L'intubation trachéale chez le brûlé de la face et du cou au stade de séquelles peut être difficile voire impossible chez certains patients. La technique de ventilation à l'aide d'un masque laryngé ou d'intubation avec un fibroscope bronchique permet de résoudre la plupart des problèmes d'intubation difficile. Les Auteurs rapportent deux observations chez deux patientes porteuses de séquelles de brûlures de la face et du cou. PMID:21991028

  8. Teton Wilderness, Teton Corridor, and Du Noir addition to Washakie Wilderness, Wyoming

    SciTech Connect

    Antweiler, J.C.; Williams, F.E.

    1984-01-01

    Field investigations were conducted during the summers of 1972, 1973, and 1974 by the USGS and the USBM to evaluate the mineral-resource potential of the Teton Wilderness, the Teton Corridor, and the Du Noir Addition to the Washakie Wilderness. As a result of this study it was determined that there is little promise for the occurrence of metallic mineral resources, but there is probable potential for oil and gas resources in two anticlines in the western part of the Teton Wilderness and in the postulated Younts Basin in the eastern part of the wilderness and the eastern part of the Du Noir Addition. The Whetstone anticline is the largest.

  9. Nanobridge SQUIDs as calorimetric inductive particle detectors

    NASA Astrophysics Data System (ADS)

    Gallop, John; Cox, David; Hao, Ling

    2015-08-01

    Superconducting transition edge sensors (TESs) have made dramatic progress since their invention some 65 years ago (Andrews et al 1949 Phys. Rev. 76 154-155 Irwin and Hilton 2005 Topics Appl. Phys. 99 63-149) until now there are major imaging arrays of TESs with as many as 7588 separate sensors. These are extensively used by astronomers for some ground-breaking observations (Hattori et al 2013 Nucl. Instrum. Methods Phys. Res. A 732 299-302). The great success of TES systems has tended to overshadow other superconducting sensor developments. However there are other types (Sobolewski et al 2003 IEEE Trans. Appl. Supercond. 13 1151-7 Hadfield 2009 Nat. Photonics 3 696-705) which are discussed in papers within this special edition of the journal. Here we describe a quite different type of detector, also applicable to single photon detection but possessing possible advantages (higher sensitivity, higher operating temperature) over the conventional TES, at least for single detectors.

  10. Calorimetric measurement of energy of ultrasonic cleaners

    SciTech Connect

    Harding, W.B.

    1994-11-01

    The development of a calorimeter that measured the power within an ultrasonic cleaning tank is presented. The principle involved is explained. Several types of calorimeter that were tested are described. Measurement of the power in an ultrasonic cleaner permits: (1) comparing different ultrasonic cleaners; (2) monitoring the performance of a specific cleaner; (3) measuring the distribution of power in a cleaning tank, and (4) evaluating the effects of process variables on the power.