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Sample records for polarization resistance values

  1. Standard test method for conducting potentiodynamic polarization resistance measurements

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1997-01-01

    1.1 This test method covers an experimental procedure for polarization resistance measurements which can be used for the calibration of equipment and verification of experimental technique. The test method can provide reproducible corrosion potentials and potentiodynamic polarization resistance measurements. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  2. Polarization encoded all-optical multi-valued shift operators

    Science.gov (United States)

    Roy, Jitendra Nath; Bhowmik, Panchatapa

    2014-08-01

    Polarization encoded multi-valued (both ternary and quaternary logic) shift operators have been designed using linear optical devices only. There are six ternary and 24 quaternary shift operators in multi-valued system. These are also known as reversible literals. This circuit will be useful in future all-optical multi-valued logic based information processing system. Different states of polarization of light are taken as different logic states.

  3. Effect of composition on the polarization and ohmic resistances of ...

    Indian Academy of Sciences (India)

    2017-06-09

    Jun 9, 2017 ... Keywords. Solid oxide fuel cell; composite cathodes; polarization resistance; ohmic resistance; impedance spectroscopy. 1. Introduction ... cathode electrode and increase in the number of TPB's. ORR in LSM or LSM/YSZ ...... participation of increased number of TPB's from the cathode. Increased number of ...

  4. Effect of composition on the polarization and ohmic resistances of ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 40; Issue 3. Effect of composition on the polarization and ohmic resistances of LSM/YSZ composite cathodes in solid oxide fuel cell. B SHRI PRAKASH S SENTHIL KUMAR S T ARUNA. Volume 40 Issue 3 June 2017 pp 441-452 ...

  5. Effect of composition on the polarization and ohmic resistances of ...

    Indian Academy of Sciences (India)

    However, the ohmic resistance was highest for the same composition and amounted to 60% of the total resistance value. Compositional dependence of resistances has been explained based on the variations of the triple phase boundaries and width of the O 2 −ion migration path with the composition of the electrode.

  6. Conditioned Reinforcement Value and Resistance to Change

    Science.gov (United States)

    Shahan, Timothy A.; Podlesnik, Christopher A.

    2008-01-01

    Three experiments examined the effects of conditioned reinforcement value and primary reinforcement rate on resistance to change using a multiple schedule of observing-response procedures with pigeons. In the absence of observing responses in both components, unsignaled periods of variable-interval (VI) schedule food reinforcement alternated with…

  7. Apparent resistivity and spectral induced polarization in the submarine environment

    Directory of Open Access Journals (Sweden)

    HERCULES DE SOUZA

    2001-09-01

    Full Text Available Relatively few investigations have employed electrical methods in the submarine environment, which may be promising for mineral deposits or threatened by environmental problems. We have measured the electric field using both disk and bar electrodes in the sea water at three different levels: sea surface, seven meters deep, and sea bottom at a depth of ten meters, employing a 2 m spacing dipole-dipole array with 7 array spacings of investigation, and 13 values of frequencies at steps of (2N hertz, N = -2, -1, 0, 1, 2,.....10. The measurement allowed the analysis of the electric field as a function of frequency and spacing, and of the spectral induced polarization. Modelling and interpretation of the apparent resistivity yielded a good fit with previous drilling data. Analysis of the spectrum of the complex apparent resistivity and the comparison with equivalent circuits, provided information about the grain size, the mineral composition and the major induced polarization phenomenon occurring below the sea. Therefore the result of the present research show the feasibility of measuring the variation of seawater resistivity in situ, as well as the resistivity of sea bottom sediments.Relativamente poucas investigações têm empregado métodos elétricos no ambiente submarino, o qual pode ser promissor para depósitos minerais ou ameaçado por problemas ambientais. Nós medimos o campo elétrico usando eletrodos em forma de disco e de barra na água do mar, em três níveis distintos: superfície, sete metros de profundidade, e fundo do mar a dez metros de profundidade, empregando um dispositivo dipolo-dipolo com 2m de afastamento, 7 níveis de investigação e 13 valores de freqüência a intervalos de (2N hertz, N = -2, -1, 0, 1, 2, ... 10. A medida permitiu a análise do campo elétrico como uma função de freqüência e afastamento, e da polarização induzida espectral. A modelagem e a interpretação da resistividade aparente se ajustaram bem

  8. Building Better Electrodes for Electrical Resistivity and Induced Polarization Data

    Science.gov (United States)

    Adkins, P. L.; La Brecque, D. J.

    2007-12-01

    In the third year of a project to understand and mitigate the systematic noise in resistivity and induced polarization measurements, we put a significant effort into understanding and developing better electrodes. The simple metal electrodes commonly used for both transmitting and receiving of electrical geophysical data are likely the Achilles" heal of the resistivity method. Even stainless steel, a commonly used electrode material because of its durability, showed only average results in laboratory tests for electrode noise. Better results have been found with non-polarizing metal-metal salt electrodes, which are widely used as surface electrodes and in IP surveys. But although they produce small measurement errors, they are not durable enough for in-situ borehole resistivity surveys, and often contain compounds that are toxic to the environment. They are also very seldom used as transmitters. In laboratory studies, we are exploring other materials and configurations for low-noise compound electrodes that will be nontoxic, inexpensive, and durable and can be used as both transmitters and receivers. Testing of the electrical noise levels of electrodes is an arduous task involving repeated measurements under varying conditions at field scales. Thus it is important to find methods of sorting out likely candidates from the mass of possible electrode configurations and construction methods. Testing of electrode impedance versus current density appears to provide simple criteria for predicting the suitability of electrodes. The best electrodes show relatively low overall contact impedance, relatively small changes in impedance with increased current density, and relatively small changes in impedance with time. Furthermore it can be shown that resistivity and induced polarization performance of electrodes is strongly correlated, so that methods of finding electrodes with low impedance and good direct current performance usually provide better quality induced

  9. Anthropogenic antibiotic resistance genes mobilization to the polar regions.

    Science.gov (United States)

    Hernández, Jorge; González-Acuña, Daniel

    2016-01-01

    Anthropogenic influences in the southern polar region have been rare, but lately microorganisms associated with humans have reached Antarctica, possibly from military bases, fishing boats, scientific expeditions, and/or ship-borne tourism. Studies of seawater in areas of human intervention and proximal to fresh penguin feces revealed the presence of Escherichia coli strains least resistant to antibiotics in penguins, whereas E. coli from seawater elsewhere showed resistance to one or more of the following antibiotics: ampicillin, tetracycline, streptomycin, and trim-sulfa. In seawater samples, bacteria were found carrying extended-spectrum β-lactamase (ESBL)-type CTX-M genes in which multilocus sequencing typing (MLST) showed different sequence types (STs), previously reported in humans. In the Arctic, on the contrary, people have been present for a long time, and the presence of antibiotic resistance genes (ARGs) appears to be much more wide-spread than was previously reported. Studies of E coli from Arctic birds (Bering Strait) revealed reduced susceptibility to antibiotics, but one globally spreading clone of E. coli genotype O25b-ST131, carrying genes of ESBL-type CTX-M, was identified. In the few years between sample collections in the same area, differences in resistance pattern were observed, with E. coli from birds showing resistance to a maximum of five different antibiotics. Presence of resistance-type ESBLs (TEM, SHV, and CTX-M) in E. coli and Klebsiella pneumoniae was also confirmed by specified PCR methods. MLST revealed that those bacteria carried STs that connect them to previously described strains in humans. In conclusion, bacteria previously related to humans could be found in relatively pristine environments, and presently human-associated, antibiotic-resistant bacteria have reached a high global level of distribution that they are now found even in the polar regions.

  10. Anthropogenic antibiotic resistance genes mobilization to the polar regions

    Directory of Open Access Journals (Sweden)

    Jorge Hernández

    2016-12-01

    Full Text Available Anthropogenic influences in the southern polar region have been rare, but lately microorganisms associated with humans have reached Antarctica, possibly from military bases, fishing boats, scientific expeditions, and/or ship-borne tourism. Studies of seawater in areas of human intervention and proximal to fresh penguin feces revealed the presence of Escherichia coli strains least resistant to antibiotics in penguins, whereas E. coli from seawater elsewhere showed resistance to one or more of the following antibiotics: ampicillin, tetracycline, streptomycin, and trim-sulfa. In seawater samples, bacteria were found carrying extended-spectrum β-lactamase (ESBL-type CTX-M genes in which multilocus sequencing typing (MLST showed different sequence types (STs, previously reported in humans. In the Arctic, on the contrary, people have been present for a long time, and the presence of antibiotic resistance genes (ARGs appears to be much more wide-spread than was previously reported. Studies of E coli from Arctic birds (Bering Strait revealed reduced susceptibility to antibiotics, but one globally spreading clone of E. coli genotype O25b-ST131, carrying genes of ESBL-type CTX-M, was identified. In the few years between sample collections in the same area, differences in resistance pattern were observed, with E. coli from birds showing resistance to a maximum of five different antibiotics. Presence of resistance-type ESBLs (TEM, SHV, and CTX-M in E. coli and Klebsiella pneumoniae was also confirmed by specified PCR methods. MLST revealed that those bacteria carried STs that connect them to previously described strains in humans. In conclusion, bacteria previously related to humans could be found in relatively pristine environments, and presently human-associated, antibiotic-resistant bacteria have reached a high global level of distribution that they are now found even in the polar regions.

  11. Effect of composition on the polarization and ohmic resistances of ...

    Indian Academy of Sciences (India)

    2017-06-09

    % of the total resistance value. Compositional dependence of ..... C due to our experimental limitations. However, it would not have any ... TPB's are present) suggest the formation of face-to-face con- tacts between the cathode ...

  12. Polarization-coupled tunable resistive behavior in oxide ferroelectric heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Gruverman, Alexei [Univ. of Nebraska, Lincoln, NE (United States); Tsymbal, Evgeny Y. [Univ. of Nebraska, Lincoln, NE (United States); Eom, Chang-Beom [Univ. of Wisconsin, Madison, WI (United States)

    2017-05-03

    This research focuses on investigation of the physical mechanism of the electrically and mechanically tunable resistive behavior in oxide ferroelectric heterostructures with engineered interfaces realized via a strong coupling of ferroelectric polarization with tunneling electroresistance and metal-insulator (M-I) transitions. This report describes observation of electrically conductive domain walls in semiconducting ferroelectrics, voltage-free control of resistive switching and demonstration of a new mechanism of electrical control of 2D electron gas (2DEG) at oxide interfaces. The research goals are achieved by creating strong synergy between cutting-edge fabrication of epitaxial single-crystalline complex oxides, nanoscale electrical characterization by scanning probe microscopy and theoretical modeling of the observed phenomena. The concept of the ferroelectric devices with electrically and mechanically tunable nonvolatile resistance represents a new paradigm shift in realization of the next-generation of non-volatile memory devices and low-power logic switches.

  13. Validation of External Corrosion Growth-Rate Using Polarization Resistance and Soil Properties

    Science.gov (United States)

    2010-08-01

    The research project evaluated the use of the Linear Polarization Resistance (LPR) and the Electric Resistance (ER) technologies in estimating the external corrosion growth rates of buried steel pipelines. This was achieved by performing laboratory a...

  14. Three-dimensional induced polarization data inversion for complex resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Commer, M.; Newman, G.A.; Williams, K.H.; Hubbard, S.S.

    2011-03-15

    The conductive and capacitive material properties of the subsurface can be quantified through the frequency-dependent complex resistivity. However, the routine three-dimensional (3D) interpretation of voluminous induced polarization (IP) data sets still poses a challenge due to large computational demands and solution nonuniqueness. We have developed a flexible methodology for 3D (spectral) IP data inversion. Our inversion algorithm is adapted from a frequency-domain electromagnetic (EM) inversion method primarily developed for large-scale hydrocarbon and geothermal energy exploration purposes. The method has proven to be efficient by implementing the nonlinear conjugate gradient method with hierarchical parallelism and by using an optimal finite-difference forward modeling mesh design scheme. The method allows for a large range of survey scales, providing a tool for both exploration and environmental applications. We experimented with an image focusing technique to improve the poor depth resolution of surface data sets with small survey spreads. The algorithm's underlying forward modeling operator properly accounts for EM coupling effects; thus, traditionally used EM coupling correction procedures are not needed. The methodology was applied to both synthetic and field data. We tested the benefit of directly inverting EM coupling contaminated data using a synthetic large-scale exploration data set. Afterward, we further tested the monitoring capability of our method by inverting time-lapse data from an environmental remediation experiment near Rifle, Colorado. Similar trends observed in both our solution and another 2D inversion were in accordance with previous findings about the IP effects due to subsurface microbial activity.

  15. Polarization dependent asymmetric magneto-resistance features in nanocrystalline diamond films

    International Nuclear Information System (INIS)

    Bhattacharyya, Somnath; Churochkin, Dmitry

    2014-01-01

    Polar angle-dependence of magneto-resistance (AMR) in heavily nitrogen-incorporated ultra-nanocrystalline diamond (UNCD) films is recorded by applying high magnetic fields, which shows strong anisotropic features at low temperatures. The temperature-dependence of MR and AMR can reveal transport in the weak-localization regime, which is explained by using a superlattice model for arbitrary values of disorder and angles. While a propagative Fermi surface model explains the negative MR features for low degree of disorder the azimuthal angle-dependent MR shows field dependent anisotropy due to the aligned conducting channels on the layers normal to film growth direction. The analysis of MR and AMR can extract the temperature dependence of dephasing time with respect to the elastic scattering time which not only establishes quasi-two dimensional features in this system but also suggests a potential application in monitoring the performance of UNCD based quantum devices.

  16. Results of polarization resistance and impedance of steel bars embedded in carbonated concrete contaminated with chlorides

    International Nuclear Information System (INIS)

    Andrade, C.; Alonso, C.; Gonzalez, J.A.

    1989-01-01

    Laboratory results of the corrosion rate of steel embedded in carbonated concrete contaminated with chlorides determined through the Polarization Resistance method are presented here as examples of the possibilities offered by this technique in order to monitor the reinforcement corrosion process. The Rp technique has the advantages of fast response, simple and relatively accurate. Contrasts with gravimetric losses are presented. The A.C. Impedance measurements determined on the same specimens are also presented. The difficulties found in the interpretation of the results are stressed. R T values cannot easily be obtained. Several electrical circuits which may model the behaviour of the steel/concrete system are discussed. Finally, comments on the basic criteria to interpret results of both techniques are given. (author) 4 refs., 6 figs

  17. Design of polarization encoded all-optical 4-valued MAX logic gate and its applications

    Science.gov (United States)

    Chattopadhyay, Tanay; Nath Roy, Jitendra

    2013-07-01

    Quaternary maximum (QMAX) gate is one type of multi-valued logic gate. An all-optical scheme of polarization encoded quaternary (4-valued) MAX logic gate with the help of Terahertz Optical Asymmetric Demultiplexer (TOAD) based fiber interferometric switch is proposed and described. For the quaternary information processing in optics, the quaternary number (0, 1, 2, 3) can be represented by four discrete polarized states of light. Numerical simulation result confirming the described methods is given in this paper. Some applications of MAX gate in logical operation and memory device are also given.

  18. Multi-polar resistance switching and memory effect in copper phthalocyanine junctions

    International Nuclear Information System (INIS)

    Qiao Shi-Zhu; Kang Shi-Shou; Li Qiang; Zhong Hai; Kang Yun; Yu Shu-Yun; Han Guang-Bing; Yan Shi-Shen; Mei Liang-Mo; Qin Yu-Feng

    2014-01-01

    Copper phthalocyanine junctions, fabricated by magnetron sputtering and evaporating methods, show multi-polar (unipolar and bipolar) resistance switching and the memory effect. The multi-polar resistance switching has not been observed simultaneously in one organic material before. With both electrodes being cobalt, the unipolar resistance switching is universal. The high resistance state is switched to the low resistance state when the bias reaches the set voltage. Generally, the set voltage increases with the thickness of copper phthalocyanine and decreases with increasing dwell time of bias. Moreover, the low resistance state could be switched to the high resistance state by absorbing the phonon energy. The stability of the low resistance state could be tuned by different electrodes. In Au/copper phthalocyanine/Co system, the low resistance state is far more stable, and the bipolar resistance switching is found. Temperature dependence of electrical transport measurements demonstrates that there are no obvious differences in the electrical transport mechanism before and after the resistance switching. They fit quite well with Mott variable range hopping theory. The effect of Al 2 O 3 on the resistance switching is excluded by control experiments. The holes trapping and detrapping in copper phthalocyanine layer are responsible for the resistance switching, and the interfacial effect between electrodes and copper phthalocyanine layer affects the memory effect. (interdisciplinary physics and related areas of science and technology)

  19. Angular and Polarization Response of Multimode Sensors with Resistive-Grid Absorbers

    Science.gov (United States)

    Kusaka, Akito; Wollack, Edward J.; Stevenson, Thomas R.

    2014-01-01

    High sensitivity receiver systems with near ideal polarization sensitivity are highly desirable for development of millimeter and sub-millimeter radio astronomy. Multimoded bolometers provide a unique solution to achieve such sensitivity, for which hundreds of single-mode sensors would otherwise be required. The primary concern in employing such multimoded sensors for polarimetery is the control of the polarization systematics. In this paper, we examine the angular- and polarization- dependent absorption pattern of a thin resistive grid or membrane, which models an absorber used for a multimoded bolometer. The result shows that a freestanding thin resistive absorber with a surface resistivity of eta/2, where eta is the impedance of free space, attains a beam pattern with equal E- and H-plane responses, leading to zero cross polarization. For a resistive-grid absorber, the condition is met when a pair of grids is positioned orthogonal to each other and both have a resistivity of eta/2. When a reflective backshort termination is employed to improve absorption efficiency, the cross-polar level can be suppressed below -30 dB if acceptance angle of the sensor is limited to < or approx. 60deg. The small cross-polar systematics have even-parity patterns and do not contaminate the measurements of odd-parity polarization patterns, for which many of recent instruments for cosmic microwave background are designed. Underlying symmetry that suppresses these cross-polar systematics is discussed in detail. The estimates and formalism provided in this paper offer key tools in the design consideration of the instruments using the multimoded polarimeters.

  20. 2D Resistivity and Induced Polarization Measurement for Manganese Ore Exploration

    Science.gov (United States)

    Srigutomo, Wahyu; Trimadona; Pratomo, Prihandhanu M.

    2016-08-01

    2D Resistivity and Induced Polarization (IP) survey was conducted to delineate the presence of minerals containing manganese in form of manganese ore. The resistivity method concerns with resistivity (ohm.m) of rocks which indicates the electrical properties in terms of ability to resist the flow of electrical current. The presence of manganese in rocks generally lowers the resistivity. The Induced Polarization (IP) method deals with chargeability (in msec) which indicates the strength of polarization effects experienced by ions in the vicinity of metallic grains in rock. The presence of manganese in rocks increases the chargeability of the rock when measured using IP method. The low resistivity zones (resistivity zones may have been influenced by the presence of clay or weathered soil. In this case, the high chargeability zones will help in confirming the prospective zones caused by manganese ore. The thicknesses of the manganese ore layer vary from about 5 to 20 m based on the cross-sections. Based on the results, we estimated the geometry of the associated manganese prospective zones for resistivity (10 msec).

  1. Resistance Values in Palestinian Hip-hop Music

    OpenAIRE

    Alindah, Lutfiyah

    2012-01-01

    This research aims to describe popular culture of Palestine Hip-Hop and the values of songs. This research has purposes 1) to describe popular culture in Palestine Hip-Hop, and 2) to find resistance value in hip-hop songs. This research used popular culture approach of Adorno that analyzes three songs of DAM group, they are Who is the Terrorist?, Ghareeb fi Biladi, and Olive Trees. This research shows that 1) Hip-Hop music is the source of resistance Palestine through music media, 2) three of...

  2. Electrical Resistivity Tomography and Induced Polarization for Mapping the Subsurface of Alluvial Fans: A Case Study in Punata (Bolivia

    Directory of Open Access Journals (Sweden)

    Andres Gonzales Amaya

    2016-11-01

    Full Text Available Conceptual models of aquifer systems can be refined and complemented with geophysical data, and they can assist in understanding hydrogeological properties such as groundwater storage capacity. This research attempts to use geoelectrical methods, Electrical Resistivity Tomography and Induced Polarization parameters, for mapping the subsurface in alluvial fans and to demonstrate its applicability; the Punata alluvial fan was used as a case study. The resistivity measurements proved to be a good tool for mapping the subsurface in the fan, especially when used in combination with Induced Polarization parameters (i.e., Normalized Chargeability. The Punata alluvial fan characterization indicated that the top part of the subsurface is composed of boulders in a matrix of finer particles and that the grain size decreases with depth; the electrical resistivity of these deposits ranged from 200 to 1000 Ωm, while the values of normalized chargeability were lower than 0.05 mS/m. The bottom of the aquifer system consisted of a layer with high clay content, and the resistivity ranged from 10 to 100 Ωm, while the normalized chargeability is higher than 0.07 mS/m. With the integration of these results and lithological information, a refined conceptual model is proposed; this model gives a more detailed description of the local aquifer system. It can be concluded that geoelectrical methods are useful for mapping aquifer systems in alluvial fans.

  3. Lithological characterization of a contaminated site using Direct current resistivity and time domain Induced Polarization

    DEFF Research Database (Denmark)

    Maurya, Pradip Kumar; Fiandaca, Gianluca; Auken, Esben

    study a large contaminated site in Denmark was investigated using direct current resistivity and time domain induced polarization (DCIP). For this purpose 14 profiles were collected alongside a stream in order to investigate the contamination and delineate the lithological units. 2D inversion using...

  4. Resistivity, induced polarization, and self-potential methods in geothermal exploration

    Energy Technology Data Exchange (ETDEWEB)

    Ward, S.H.; Sill, W.R.

    1982-01-01

    An overview of the literature is presented. This is followed by a statement of some elementary electromagnetic theory necessary to establish the MKS system of units and the fundamental physics governing electrical methods of exploration. Next there is presented a reasonably detailed discussion of the electrical properties of earth materials including normal mode of conduction, surface conduction, electrode polarization, membrane polarization, semiconduction, melt conduction, real and complex resistivity, and the origin of self-potentials in geothermal systems. To illustrate how electrical methods are used within the framework of integrated geological, geochemical, and geophysical exploration, the case history of the Monroe-Red Hill hot springs system is presented.

  5. Genomic Prediction of Genetic Values for Resistance to Wheat Rusts

    Directory of Open Access Journals (Sweden)

    Leonardo Ornella

    2012-11-01

    Full Text Available Durable resistance to the rust diseases of wheat ( L. can be achieved by developing lines that have race-nonspecific adult plant resistance conferred by multiple minor slow-rusting genes. Genomic selection (GS is a promising tool for accumulating favorable alleles of slow-rusting genes. In this study, five CIMMYT wheat populations evaluated for resistance were used to predict resistance to stem rust ( and yellow rust ( using Bayesian least absolute shrinkage and selection operator (LASSO (BL, ridge regression (RR, and support vector regression with linear or radial basis function kernel models. All parents and populations were genotyped using 1400 Diversity Arrays Technology markers and different prediction problems were assessed. Results show that prediction ability for yellow rust was lower than for stem rust, probably due to differences in the conditions of infection of both diseases. For within population and environment, the correlation between predicted and observed values (Pearson’s correlation [ρ] was greater than 0.50 in 90% of the evaluations whereas for yellow rust, ρ ranged from 0.0637 to 0.6253. The BL and RR models have similar prediction ability, with a slight superiority of the BL confirming reports about the additive nature of rust resistance. When making predictions between environments and/or between populations, including information from another environment or environments or another population or populations improved prediction.

  6. Polarization and resistivity measurements of post-crystallization changes in amorphous Fe-B-Si alloys

    International Nuclear Information System (INIS)

    Chattoraj, I.; Bhattamishra, A.K.; Mitra, A.

    1993-01-01

    The effects of grain growth and compositional changes on the electrochemical behavior and the resistivity of amorphous iron-boron-silicon (Fe 77.5 B 15 Si 7.5 ) alloys after crystallization were studied. Deterioration of the protective passive film was observed, along with increased annealing. Potentiodynamic polarization provided excellent information about microstructural and chemical changes. It was concluded that electrochemical measurements could be used in conjunction with resistivity measurements in direct studies of grain growth and chemical changes occurring in different phases of the devitrified alloy

  7. The use of the multiple-gradient array for geoelectrical resistivity and induced polarization imaging

    Science.gov (United States)

    Aizebeokhai, Ahzegbobor P.; Oyeyemi, Kehinde D.

    2014-12-01

    The use of most conventional electrode configurations in electrical resistivity survey is often time consuming and labour intensive, especially when using manual data acquisition systems. Often, data acquisition teams tend to reduce data density so as to speed up field operation thereby reducing the survey cost; but this could significantly degrade the quality and resolution of the inverse models. In the present work, the potential of using the multiple-gradient array, a non-conventional electrode configuration, for practical cost effective and rapid subsurface resistivity and induced polarization mapping was evaluated. The array was used to conduct 2D resistivity and time-domain induced polarization imaging along two traverses in a study site at Ota, southwestern Nigeria. The subsurface was characterised and the main aquifer delineated using the inverse resistivity and chargeability images obtained. The performance of the multiple-gradient array was evaluated by correlating the 2D resistivity and chargeability images with those of the conventional Wenner array as well as the result of some soundings conducted along the same traverses using Schlumberger array. The multiple-gradient array has been found to have the advantage of measurement logistics and improved image resolution over the Wenner array.

  8. Mapping geological structures in bedrock via large-scale direct current resistivity and time-domain induced polarization tomography

    DEFF Research Database (Denmark)

    Rossi, Matteo; Olsson, Per-Ivar; Johansson, Sara

    2017-01-01

    An investigation of geological conditions is always a key point for planning infrastructure constructions. Bedrock surface and rock quality must be estimated carefully in the designing process of infrastructures. A large direct-current resistivity and time-domain induced-polarization survey has......, there are northwest-trending Permian dolerite dykes that are less deformed. Four 2D direct-current resistivity and time-domain induced-polarization profiles of about 1-km length have been carefully pre-processed to retrieve time-domain induced polarization responses and inverted to obtain the direct......-current resistivity distribution of the subsoil and the phase of the complex conductivity using a constant-phase angle model. The joint interpretation of electrical resistivity and induced-polarization models leads to a better understanding of complex three-dimensional subsoil geometries. The results have been...

  9. 77 GHz MEMS antennas on high-resistivity silicon for linear and circular polarization

    KAUST Repository

    Sallam, M. O.

    2011-07-01

    Two new MEMS antennas operating at 77 GHz are presented in this paper. The first antenna is linearly polarized. It possesses a vertical silicon wall that carries a dipole on top of it. The wall is located on top of silicon substrate covered with a ground plane. The other side of the substrate carries a microstrip feeding network in the form of U-turn that causes 180 phase shift. This phase-shifter feeds the arms of the dipole antenna via two vertical Through-Silicon Vias (TSVs) that go through the entire wafer. The second antenna is circularly polarized and formed using two linearly polarized antennas spatially rotated with respect to each other by 90 and excited with 90 phase shift. Both antennas are fabricated using novel process flow on a single high-resistivity silicon wafer via bulk micromachining. Only three processing steps are required to fabricate these antennas. The proposed antennas have appealing characteristics, such as high polarization purity, high gain, and high radiation efficiency. © 2011 IEEE.

  10. Comparison of radiance and polarization values observed in the Mediterranean Sea and simulated in a Monte Carlo model

    DEFF Research Database (Denmark)

    Adams, J.T.; Aas, E.; Højerslev, N.K.

    2002-01-01

    Measurements of the radiance and degree of polarization made in 1971 in the Mediterranean Sea are presented along with the simulation of all observed quantities by a Monte Carlo technique. It is shown that our independent scattering treatment utilizing a Stokes vector formalism to describe...... the polarization state of the light field produces remarkably good agreement with those values measured in situ. (C) 2002 Optical Society of America...

  11. The resistivity imaging application in groundwater exploration: resistivity value and soil type

    International Nuclear Information System (INIS)

    Mohd Khardzir Husain

    2006-01-01

    Malaysia is rich in water resources. Water development has fueled socio-economic development of the country during the past decades. Dams and thousands of kilometers of pipes and canals divert water from the rivers to sustain domestic, industrial and agricultural needs. Lately, the water situation for the country has changed from one of relative abundance to one of relative scarcity. The population growth and the expansion in urbanization, industrialization and irrigated agriculture are imposing rapidly growing demands and pressure on the water resources, besides contributing to the rising water pollution. Surface water resource, the traditional source of water supply in the past, has become inadequate in some areas. The problem becomes more acute in areas where surface water is affected by the increasing pollution from industrial and agricultural waste and where changes in land have adversely affected the quantity and quality of surface water supply. The development of groundwater as a source of water supply or as an alternative source is therefore a timely outlook. Lack in groundwater development will becoming disasters to country. Electrical resistivity had been used in groundwater exploration to get an accuracy result in a short time. This method measures the apparent resistivity of the subsurface, including effects of any or all of the following: soil type, bedrock fractures, contaminants and ground water. Variations in electrical resistivity may indicate changes in composition, layer thickness or contaminant levels. The resistivity values obtained from various groundwater exploration and experimental sites shows that the value differs also in related to the soil type. (Author)

  12. Large 3D resistivity and induced polarization acquisition using the Fullwaver system: towards an adapted processing methodology

    Science.gov (United States)

    Truffert, Catherine; Leite, Orlando; Gance, Julien; Texier, Benoît; Bernard, Jean

    2017-04-01

    Driven by needs in the mineral exploration market for ever faster and ever easier set-up of large 3D resistivity and induced polarization, autonomous and cableless recorded systems come to the forefront. Opposite to the traditional centralized acquisition, this new system permits a complete random distribution of receivers on the survey area allowing to obtain a real 3D imaging. This work presents the results of a 3 km2 large experiment up to 600m of depth performed with a new type of autonomous distributed receivers: the I&V-Fullwaver. With such system, all usual drawbacks induced by long cable set up over large 3D areas - time consuming, lack of accessibility, heavy weight, electromagnetic induction, etc. - disappear. The V-Fullwavers record the entire time series of voltage on two perpendicular axes, for a good determination of the data quality although I-Fullwaver records injected current simultaneously. For this survey, despite good assessment of each individual signal quality, on each channel of the set of Fullwaver systems, a significant number of negative apparent resistivity and chargeability remains present in the dataset (around 15%). These values are commonly not taken into account in the inversion software although they may be due to complex geological structure of interest (e.g. linked to the presence of sulfides in the earth). Taking into account that such distributed recording system aims to restitute the best 3D resistivity and IP tomography, how can 3D inversion be improved? In this work, we present the dataset, the processing chain and quality control of a large 3D survey. We show that the quality of the data selected is good enough to include it into the inversion processing. We propose a second way of processing based on the modulus of the apparent resistivity that stabilizes the inversion. We then discuss the results of both processing. We conclude that an effort could be made on the inclusion of negative apparent resistivity in the inversion

  13. CTLA-4Ig immunotherapy of obesity-induced insulin resistance by manipulation of macrophage polarization in adipose tissues

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Masakazu, E-mail: masakazu731079@yahoo.co.jp [Department of Internal Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Inoguchi, Toyoshi, E-mail: toyoshi@intmed3.med.kyushu-u.ac.jp [Department of Internal Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Innovation Center for Medical Redox Navigation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Batchuluun, Battsetseg, E-mail: battsetseg.batchuluun@gmail.com [Department of Internal Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Sugiyama, Naonobu, E-mail: nao1@intmed1.med.kyushu-u.ac.jp [Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Kobayashi, Kunihisa, E-mail: nihisak@fukuoka-u.ac.jp [Department of Endocrinology and Diabetes Mellitus, Fukuoka University Chikushi Hospital, 1-1-1 Zokumyoin, Chikushino, Fukuoka 818-8502 (Japan); Sonoda, Noriyuki, E-mail: noriyuki@intmed3.med.kyushu-u.ac.jp [Department of Internal Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Innovation Center for Medical Redox Navigation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Takayanagi, Ryoichi, E-mail: takayana@intmed3.med.kyushu-u.ac.jp [Department of Internal Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

    2013-08-16

    Highlights: •CTLA-4Ig completely alleviates HFD-induced insulin resistance. •CTLA-4Ig reduces epididymal and subcutaneous fat tissue weight and adipocyte size. •CTLA-4Ig alters ATM polarization from inflammatory M1 to anti-inflammatory M2. •CTLA-4Ig may lead to a novel anti-obesity/inflammation/insulin resistance agent. •We identified the mechanism of the novel favorable effects of CTLA-4lg. -- Abstract: It has been established that obesity alters the metabolic and endocrine function of adipose tissue and, together with accumulation of adipose tissue macrophages, contributes to insulin resistance. Although numerous studies have reported that shifting the polarization of macrophages from M1 to M2 can alleviate adipose tissue inflammation, manipulation of macrophage polarization has not been considered as a specific therapy. Here, we determined whether cytotoxic T-lymphocyte-associated antigen-4IgG1 (CTLA-4Ig) can ameliorate insulin resistance by induction of macrophages from proinflammatory M1 to anti-inflammatory M2 polarization in the adipose tissues of high fat diet-induced insulin-resistant mice. CTLA4-Ig treatment prevented insulin resistance by changing gene expression to M2 polarization, which increased the levels of arginase 1. Furthermore, flow cytometric analysis confirmed the alteration of polarization from CD11c (M1)- to CD206 (M2)-positive cells. Concomitantly, CTLA-4Ig treatment resulted in weight reductions of epididymal and subcutaneous adipose tissues, which may be closely related to overexpression of apoptosis inhibitors in macrophages. Moreover, proinflammatory cytokine and chemokine levels decreased significantly. In contrast, CCAAT enhancer binding protein α, peroxisome proliferator-activated receptor γ, and adiponectin expression increased significantly in subcutaneous adipose tissue. This novel mechanism of CTLA-4lg immunotherapy may lead to an ideal anti-obesity/inflammation/insulin resistance agent.

  14. CTLA-4Ig immunotherapy of obesity-induced insulin resistance by manipulation of macrophage polarization in adipose tissues

    International Nuclear Information System (INIS)

    Fujii, Masakazu; Inoguchi, Toyoshi; Batchuluun, Battsetseg; Sugiyama, Naonobu; Kobayashi, Kunihisa; Sonoda, Noriyuki; Takayanagi, Ryoichi

    2013-01-01

    Highlights: •CTLA-4Ig completely alleviates HFD-induced insulin resistance. •CTLA-4Ig reduces epididymal and subcutaneous fat tissue weight and adipocyte size. •CTLA-4Ig alters ATM polarization from inflammatory M1 to anti-inflammatory M2. •CTLA-4Ig may lead to a novel anti-obesity/inflammation/insulin resistance agent. •We identified the mechanism of the novel favorable effects of CTLA-4lg. -- Abstract: It has been established that obesity alters the metabolic and endocrine function of adipose tissue and, together with accumulation of adipose tissue macrophages, contributes to insulin resistance. Although numerous studies have reported that shifting the polarization of macrophages from M1 to M2 can alleviate adipose tissue inflammation, manipulation of macrophage polarization has not been considered as a specific therapy. Here, we determined whether cytotoxic T-lymphocyte-associated antigen-4IgG1 (CTLA-4Ig) can ameliorate insulin resistance by induction of macrophages from proinflammatory M1 to anti-inflammatory M2 polarization in the adipose tissues of high fat diet-induced insulin-resistant mice. CTLA4-Ig treatment prevented insulin resistance by changing gene expression to M2 polarization, which increased the levels of arginase 1. Furthermore, flow cytometric analysis confirmed the alteration of polarization from CD11c (M1)- to CD206 (M2)-positive cells. Concomitantly, CTLA-4Ig treatment resulted in weight reductions of epididymal and subcutaneous adipose tissues, which may be closely related to overexpression of apoptosis inhibitors in macrophages. Moreover, proinflammatory cytokine and chemokine levels decreased significantly. In contrast, CCAAT enhancer binding protein α, peroxisome proliferator-activated receptor γ, and adiponectin expression increased significantly in subcutaneous adipose tissue. This novel mechanism of CTLA-4lg immunotherapy may lead to an ideal anti-obesity/inflammation/insulin resistance agent

  15. The evaluation of the polarization resistance in a tubular electrode and its application to the hydrogen electrode reaction

    International Nuclear Information System (INIS)

    Montero, M.A.; Marozzi, C.A.; Chialvo, M.R. Gennero de; Chialvo, A.C.

    2007-01-01

    An alternative method for the determination of the kinetic parameters involved in the elementary steps of the reaction mechanism of the hydrogen electrode reaction is proposed. It is based on the determination of the variation of the polarization resistance in a tubular platinum electrode with a laminar flow of electrolyte as a function of the activity of protons of the electrolyte solution. A theoretical expression that relates the experimental variables and the equilibrium polarization resistance is developed, which takes into account the current distribution along the electrode surface. The results are compared with others obtained previously, contributing to the verification of the kinetic mechanism through a completely different experimental procedure

  16. Modeling and inversion Matlab algorithms for resistivity, induced polarization and seismic data

    Science.gov (United States)

    Karaoulis, M.; Revil, A.; Minsley, B. J.; Werkema, D. D.

    2011-12-01

    M. Karaoulis (1), D.D. Werkema (3), A. Revil (1,2), A., B. Minsley (4), (1) Colorado School of Mines, Dept. of Geophysics, Golden, CO, USA. (2) ISTerre, CNRS, UMR 5559, Université de Savoie, Equipe Volcan, Le Bourget du Lac, France. (3) U.S. EPA, ORD, NERL, ESD, CMB, Las Vegas, Nevada, USA . (4) USGS, Federal Center, Lakewood, 10, 80225-0046, CO. Abstract We propose 2D and 3D forward modeling and inversion package for DC resistivity, time domain induced polarization (IP), frequency-domain IP, and seismic refraction data. For the resistivity and IP case, discretization is based on rectangular cells, where each cell has as unknown resistivity in the case of DC modelling, resistivity and chargeability in the time domain IP modelling, and complex resistivity in the spectral IP modelling. The governing partial-differential equations are solved with the finite element method, which can be applied to both real and complex variables that are solved for. For the seismic case, forward modeling is based on solving the eikonal equation using a second-order fast marching method. The wavepaths are materialized by Fresnel volumes rather than by conventional rays. This approach accounts for complicated velocity models and is advantageous because it considers frequency effects on the velocity resolution. The inversion can accommodate data at a single time step, or as a time-lapse dataset if the geophysical data are gathered for monitoring purposes. The aim of time-lapse inversion is to find the change in the velocities or resistivities of each model cell as a function of time. Different time-lapse algorithms can be applied such as independent inversion, difference inversion, 4D inversion, and 4D active time constraint inversion. The forward algorithms are benchmarked against analytical solutions and inversion results are compared with existing ones. The algorithms are packaged as Matlab codes with a simple Graphical User Interface. Although the code is parallelized for multi

  17. A lesson from science in polar extreme environments: ethics and social values for primary school

    Science.gov (United States)

    La Longa, Federica; Crescimbene, Massimo; Alfonsi, Lucilla; Romano, Vincenzo; Cesaroni, Claudio

    2015-04-01

    One of the relevant objectives of the researchers should be filling the gap between the scientific research and the school. Such objective should be pursued methodically, through commitment, foresight and cooperation. In this frame the idea to communicate and to share the experience of the scientific research in Antarctica with the public and with the school is a challenge that a team of INGV researchers, engaged for many years in scientific missions in Antarctica, carries on with great enthusiasm within the several outreach activities of the Italian National Program for Antarctic Research (PNRA). The outreach activities, aiming to disseminate the knowledge and the culture of the polar regions, have been mainly addressed to a public of adults and students of the secondary school (11-19 years). Recently, the researchers matured the need to realize outreach paths addressed to pupils of the primary school (8-10 years), taking the advantage of the multidisciplinary themes offered by the Antarctic research. The present work reports the experience of the outreach laboratory "On a mission to the South Pole", realized in the frame of events organized by INGV (ScienzAperta 2012 e 2014) and dedicated to the primary school. The educational themes developed within the laboratory concern the research in Antarctica, with particular focus on the human aspects, the geophysics and the progress of new technologies. The innovative aspect of the laboratory stands in the strategy to deal with Antarctica with an educational aim, proposing Antarctica as a natural laboratory, not only from a scientific point of view, but also as a laboratory of shared human experiences. The didactic path, based on interactive methodology that uses the role-paly and the experiential activities, enable the children to acquire the knowledge on Antarctica (knowledge); to explore the Antarctic characteristics as a natural laboratory and to experiment an emotional education through individual and team

  18. Beta4 integrin-dependent formation of polarized three-dimensionalarchitecture confers resistance to apoptosis in normal and malignantmammary epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Valerie M.; Lelievre, Sophie; Lakins, Johnathon N.; Chrenek, Micah A.; Jones, Jonathan C.R.; Giancotti, Filippo; Werb, Zena; Bissell, Mina J.

    2002-08-27

    Tumor cells can evade chemotherapy by acquiring resistanceto apoptosis. We investigated the molecular mechanism whereby malignantand nonmalignant mammary epithelial cells become insensitive toapoptosis. We show that regardless of growth status formation ofpolarized, three-dimensional structures driven by basement membraneconfers protection to apoptosis in both nonmalignant and malignantmammary epithelial cells. By contrast, irrespective of their malignantstatus, nonpolarized structures are sensitive to induction of apoptosis.Resistance to apoptosis requires ligation of beta4 integrins, whichregulates tissue polarity, hemidesmosome formation and NFkB activation.Expression of beta4 integrin that lacks the hemidesmosome targetingdomain interferes with tissue polarity and NFkB activation and permitsapoptosis. These results indicate that integrin-induced polarity maydrive tumor cell resistance to apoptosis-inducing agents via effects onNFkB.

  19. Mapping geological structures in bedrock via large-scale direct current resistivity and time-domain induced polarization tomography

    DEFF Research Database (Denmark)

    Rossi, Matteo; Olsson, Per-Ivar; Johansson, Sara

    2017-01-01

    An investigation of geological conditions is always a key point for planning infrastructure constructions. Bedrock surface and rock quality must be estimated carefully in the designing process of infrastructures. A large direct-current resistivity and time-domain induced-polarization survey has b...... been performed in Dalby, Lund Municipality, southern Sweden, with the aim of mapping lithological variations in bedrock. The geology at the site is characterised by Precambrian granitic gneisses and amphibolites, which are intensely deformed, fractured, and partly weathered. In addition......-polarization profiles. The direct-current resistivity and time-domain induced-polarization methodology proved to be a suitable technique for extensively mapping weathered zones with poor geotechnical characteristics and tectonic structures, which can lead to severe problems for infrastructure construction and....../or constitute risk zones for aquifer contamination....

  20. Complementary resistive switching in BaTiO{sub 3}/NiO bilayer with opposite switching polarities

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shuo [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Institut d’Electronique de Micro-électronique et de Nanotechnologie (IEMN), CNRS, Université des Sciences et Technologies de Lille, avenue Poincaré, BP 60069, 59652, Villeneuve d’Ascq cedex (France); Wei, Xianhua, E-mail: weixianhua@swust.edu.cn [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Lei, Yao [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronics Science and Technology of China, Chengdu 610054 (China); Yuan, Xincai [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Zeng, Huizhong [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronics Science and Technology of China, Chengdu 610054 (China)

    2016-12-15

    Graphical abstract: Au/BaTiO{sub 3}/NiO/Pt bilayer device shows complementary resistive switching (CRS) without electroforming which is mainly ascribed to anti-serial stack of two RRAM cells with bipolar behaviors. - Highlights: • Complementary resistive switching (CRS) has been investigated in Au/BaTiO{sub 3}/NiO/Pt by stacking the two elements with different switching types. • The realization of complementary resistive switching (CRS) is mainly ascribed to the anti-serial stack of two RRAM cells with bipolar behaviors. • Complementary resistive switching (CRS) in bilayer is effective to solve the sneak current problem briefly and economically. - Abstract: Resistive switching behaviors have been investigated in the Au/BaTiO{sub 3}/NiO/Pt structure by stacking the two elements with different switching types. The conducting atomic force microscope measurements on BaTiO{sub 3} thin films and NiO thin films suggest that with the same active resistive switching region, the switching polarities in the two semiconductors are opposite to each other. It is in agreement with the bipolar hysteresis I–V curves with opposite switching polarities for single-layer devices. The bilayer devices show complementary resistive switching (CRS) without electroforming and unipolar resistive switching (URS) after electroforming. The coexistence of CRS and URS is mainly ascribed to the co-effect of electric field and Joule heating mechanisms, indicating that changeable of resistance in this device is dominated by the redistribution of oxygen vacancies in BaTiO{sub 3} and the formation, disruption, restoration of conducting filaments in NiO. CRS in bilayer with opposite switching polarities is effective to solve the sneak current without the introduction of any selector elements or an additional metal electrode.

  1. Estimating SPT-N Value Based on Soil Resistivity using Hybrid ANN-PSO Algorithm

    Science.gov (United States)

    Nur Asmawisham Alel, Mohd; Ruben Anak Upom, Mark; Asnida Abdullah, Rini; Hazreek Zainal Abidin, Mohd

    2018-04-01

    Standard Penetration Resistance (N value) is used in many empirical geotechnical engineering formulas. Meanwhile, soil resistivity is a measure of soil’s resistance to electrical flow. For a particular site, usually, only a limited N value data are available. In contrast, resistivity data can be obtained extensively. Moreover, previous studies showed evidence of a correlation between N value and resistivity value. Yet, no existing method is able to interpret resistivity data for estimation of N value. Thus, the aim is to develop a method for estimating N-value using resistivity data. This study proposes a hybrid Artificial Neural Network-Particle Swarm Optimization (ANN-PSO) method to estimate N value using resistivity data. Five different ANN-PSO models based on five boreholes were developed and analyzed. The performance metrics used were the coefficient of determination, R2 and mean absolute error, MAE. Analysis of result found that this method can estimate N value (R2 best=0.85 and MAEbest=0.54) given that the constraint, Δ {\\bar{l}}ref, is satisfied. The results suggest that ANN-PSO method can be used to estimate N value with good accuracy.

  2. Student Resistance Culture against School Values: An Ethnographic Research

    Science.gov (United States)

    Karakul, Aygülen Kayahan

    2016-01-01

    Schools operating within capitalism reproduce class differences, and aim to graduate students who comply with the capitalist system. On the other hand, according to the principles of dialectical materialism, while schools aim to produce obedience, they also produce resistance to themselves at the same time. Working class children sometimes refuse…

  3. Analytic parallel-polarized light imaging technique using various light-emitting diodes: a comparison with skin conductance values.

    Science.gov (United States)

    Kim, D H; Choi, J E; Ryu, H J; Seo, S H; Kye, Y C; Ahn, H H

    2015-05-01

    The quantitative difference of the light reflected from a skin surface can be analyzed using parallel-polarized light (PPL) photography when combined with an analytic technique similar to colorimetric photography. To improve the PPL photography technique as an assessment tool for the evaluation of skin condition using light-emitting diodes (LED) of different colors. Parallel-polarized light images were taken using white and green LED illuminators. The acquired images were transformed to CIELAB coordinates. An in-house skin conductance meter was constructed to assess skin hydration level. A dermatologist evaluated the clinical grading of dryness and glossiness. These clinical severities were also compared statistically with the CIELAB values. As with the green illuminator, the correlation analysis of whole sites showed that the L* value positively correlated with age (r = 0.18677, P < 0.05), and that the a* value has negative and positive relationships with age (r = -0.20528, P < 0.05) and glossiness (r = 0.20885, P < 0.05) respectively. The correlations between CIELAB values and multiple characteristics of skin were more significant when green LED was applied than when white light was applied. In addition, coherent relationships between the grade of dryness and skin conductance values showed that visual assessment could be appropriate for the study as with objective measurement. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Arbitrary control of the polarization and intensity profiles of diffraction-attenuation-resistant beams along their propagation direction

    OpenAIRE

    Corato-Zanarella, Mateus; Dorrah, Ahmed H.; Zamboni-Rached, Michel; Mojahedi, Mo

    2017-01-01

    We report on the theory and experimental generation of a class of diffraction-attenuation-resistant beams with state of polarization (SoP) and intensity that can be controlled on demand along the propagation direction. This is achieved by a suitable superposition of Bessel beams, whose parameters are systematically chosen based on closed-form analytic expressions provided by the Frozen Waves (FWs) method. Using an amplitude-only spatial light modulator, we experimentally demonstrate three sce...

  5. Simulation of AZ-PN100 resist pattern fluctuation in X-ray lithography, including synchrotron beam polarization

    International Nuclear Information System (INIS)

    Scheckler, E.W.; Ogawa, Taro; Tanaka, Toshihiko; Takeda, Eiji; Oizumi, Hiroaki.

    1993-01-01

    A new simulation model for nanometer-scale pattern fluctuation in X-ray lithography is presented and applied to a study of AZ-PN100 negative chemical amplification resist. The exposure simulation considers polarized photons from a synchrotron radiation (SR) source. Monte Carlo simulation of Auger and photoelectron generation is followed by electron scattering simulation to determine the deposited energy distribution at the nanometer scale, including beam polarization effects. An acid-catalyst random walk model simulates the post-exposure bake (PEB) step. Fourier transform infrared (FTIR) spectroscopy and developed resist thickness measurements are used to fit PEB and rate models for AZ-PN100. A polymer removal model for development simulation predicts the macroscopic resist shape and pattern roughness. The simulated 3σ linewidth variation is in excess of 24 nm. Simulation also shows a detrimental effect if the beam polarization is perpendicular to the line. Simulation assuming a theoretical ideal exposure yields a 50 nm minimum line for standard process conditions. (author)

  6. 1-D DC Resistivity Inversion Using Singular Value Decomposition and Levenberg-Marquardt’s Inversion Schemes

    OpenAIRE

    Heriyanto, Mohammad; Srigutomo, Wahyu

    2017-01-01

    Exploration of natural or energy resources requires geophysical survey to determine the subsurface structure, such as DC resistivity method. In this research, field and synthetic data were used using Schlumberger configuration. One-dimensional (1-D) DC resistivity inversion was carried out using Singular Value Decomposition (SVD) and Levenberg-Marquardt (LM) techniques to obtain layered resistivity structure. We have developed software to perform both inversion met...

  7. Resisting the Terms of Polar Questions through "Ani" ("No")-Prefacing in Korean Conversation

    Science.gov (United States)

    Kim, Stephanie Hyeri

    2015-01-01

    This article reports on the conversation-analytic investigation of "ani" "no"-prefaced responses to polar questions in Korean conversation, when "ani" is not used as a negative response particle to negate or disconfirm the truth conditional proposition of the question. Understanding polar questions as advancing the…

  8. Values, inter-attitudinal structure, and attitude change: value accessibility can increase a related attitude's resistance to change.

    Science.gov (United States)

    Blankenship, Kevin L; Wegener, Duane T; Murray, Renee A

    2015-12-01

    Accessibility is one of the most basic structural properties of an attitude and an important factor to consider in attitude strength. Despite its importance, relatively little work has examined the role of attitude accessibility in an inter-attitudinal context, particularly as it relates to the strength of related attitudes in the network. The present research examines accessibility as a property of one attitude (toward an abstract goal or end-state, that is, a value) that might influence the strength of a different but related attitude (toward a social policy conceptually related to the value). In Study 1, a highly accessible evaluative component of a value increased resistance to change of attitudes and behavioral intentions toward a social policy related to that value. Similarly, a manipulation of value accessibility (Studies 2 and 3) led to increased resistance of attitudes and behavioral intentions toward a social policy related to that value. Implications for the role of accessibility in inter-attitudinal strength are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

  9. Direct current (DC) resistivity and Induced Polarization (IP) monitoring of active layer dynamics at high temporal resolution

    DEFF Research Database (Denmark)

    Doetsch, J.; Fiandaca, G.; Ingeman-Nielsen, Thomas

    2015-01-01

    With permafrost thawing and changes in active layer dynamics induced by climate change, interactions between biogeochemical and thermal processes in the ground are of great importance. Here, active layer dynamics have been monitored using direct current (DC) resistivity and induced polarization (...... non-intrusively and reliably image freezing patterns and their lateral variation on a 10-100 m scale that is difficult to sample by point measurements.......) measurements at high temporal resolution at a heath tundra site on Disko Island on the west coast of Greenland (69°N). Borehole sediment characteristics and subsurface temperatures supplemented the DC-IP measurements. Data acquired during the freezing period of October 2013 – February 2014 clearly image...... the soil freezing as a strong increase in resistivity. While the freezing horizon generally moves deeper with time, some variations in the freezing depth are observed along the profile. Comparison with depth-specific soil temperature indicates an exponential relationship between resistivity and below-freezing...

  10. Enhanced bipolar resistive switching behavior in polar Cr-doped barium titanate thin films without electro-forming process

    Directory of Open Access Journals (Sweden)

    Atul Thakre

    2017-12-01

    Full Text Available An enhanced, repeatable and robust resistive switching phenomenon was observed in Cr substituted BaTiO3 polar ferroelectric thin films; fabricated and deposited by the sol-gel approach and spin coating technique, respectively. An enhanced bistable bipolar resistive switching (BRS phenomenon without electro-forming process, low switching voltage (∼ 2 V and moderate retention characteristics of 104 s along with a high Roff/Ron resistance ratio ∼103 was achieved. The current conduction analysis showed that the space charge limited conduction (SCLC and Schottky emission conduction dominate in the high voltage range, while thermally active charge carriers (ohmic in the lower voltage range. The impedance spectroscopy study indicates the formation of current conducting path and rupturing of oxygen vacancies during SET and RESET process.

  11. Enhanced bipolar resistive switching behavior in polar Cr-doped barium titanate thin films without electro-forming process

    Science.gov (United States)

    Thakre, Atul; Kumar, Ashok

    2017-12-01

    An enhanced, repeatable and robust resistive switching phenomenon was observed in Cr substituted BaTiO3 polar ferroelectric thin films; fabricated and deposited by the sol-gel approach and spin coating technique, respectively. An enhanced bistable bipolar resistive switching (BRS) phenomenon without electro-forming process, low switching voltage (˜ 2 V) and moderate retention characteristics of 104 s along with a high Roff/Ron resistance ratio ˜103 was achieved. The current conduction analysis showed that the space charge limited conduction (SCLC) and Schottky emission conduction dominate in the high voltage range, while thermally active charge carriers (ohmic) in the lower voltage range. The impedance spectroscopy study indicates the formation of current conducting path and rupturing of oxygen vacancies during SET and RESET process.

  12. Polar amplification of the early Eocene indicated by δ2H values of lignin methoxyl groups of mummified wood

    Science.gov (United States)

    Anhäuser, Tobias; Hook, Benjamin; Halfar, Jochen; Greule, Markus; Keppler, Frank

    2017-04-01

    A number of well-preserved mummified wood samples have been excavated during diamond mining operations in early Eocene (55-50 Ma) kimberlite deposits located near the Arctic Circle (64° N, 110° W) in the Canadian Northwest Territories. The preserved wood, containing multi-decadal length tree-ring information, therefore allows the reconstruction of an unprecedented snapshot of terrestrial high-latitude climate during the early Eocene. Here we used wood-derived stable hydrogen isotopes (δ2H) as proxy for paleoclimatic interpretations. While cellulose extractions are commonly used for the analysis of modern wood-derived δ2H values, the mummified wood samples had been affected by selective degradation leading to a strong or even complete loss of cellulose while leaving a lignin-rich material behind. We have therefore analyzed δ2H values of the lignin methoxyl groups that have previously been shown to reflect the δ2H values of the local precipitation and can thus be used to infer paleoclimate information such as temperature changes. We applied this proxy to specimens found in three adjacent kimberlite pipes (30 km apart) which represent a range of early Eocene ages (Rb/Sr dating: 55.5 ± 0.7, 55.2 ± 0.3 and 53.3 ± 0.6 Ma [2σ standard deviation]). The δ2H values were measured at annual resolution for the three mummified wood series (length of individual time series: 82, 62 and 40 years) and the mean δ2H value of precipitation for the three decadal-scale time slices was reconstructed. Finally, we used existing relationships between early Eocene temperatures and stable isotopes in precipitation to quantify temperature changes. Warming phases such as the one covered here (culminating in the Early Eocene Climatic Optimum [52 to 50 Ma]) are commonly accompanied by a stronger increase in arctic/subarctic surface air temperatures in comparison to the global average (the ratio of these temperature differences is referred to as the polar amplification). Our estimation

  13. Arbitrary Control of Polarization and Intensity Profiles of Diffraction-Attenuation-Resistant Beams along the Propagation Direction

    Science.gov (United States)

    Corato-Zanarella, Mateus; Dorrah, Ahmed H.; Zamboni-Rached, Michel; Mojahedi, Mo

    2018-02-01

    We report on the theory and experimental generation of a class of diffraction-attenuation-resistant beams with state of polarization (SOP) and intensity that can be controlled on demand along the propagation direction. This control is achieved by a suitable superposition of Bessel beams, whose parameters are systematically chosen based on closed-form analytic expressions provided by the frozen waves method. Using an amplitude-only spatial light modulator, we experimentally demonstrate three scenarios. In the first, the SOP of a horizontally polarized beam evolves to radial polarization and is then changed to vertical polarization, with the beam intensity held constant. In the second, we simultaneously control the SOP and the longitudinal intensity profile, which is chosen such that the beam's central ring can be switched off over predefined space regions, thus generating multiple foci with different SOPs and at different intensity levels along the propagation. Finally, the ability to control the SOP while overcoming attenuation inside lossy fluids is shown experimentally. We envision our proposed method to be of great interest for many applications, such as optical tweezers, atom guiding, material processing, microscopy, and optical communications.

  14. Are preference and resistance to change convergent expressions of stimulus value?

    Science.gov (United States)

    Podlesnik, Christopher A; Jimenez-Gomez, Corina; Shahan, Timothy A

    2013-07-01

    Behavioral momentum theory asserts that preference and relative resistance to disruption depend on reinforcement rates and provide converging expressions of the conditioned value of discriminative stimuli. However, preference and resistance to disruption diverge when assessing preference during brief extinction probes. We expanded upon this opposing relation by arranging target stimuli signaling equal variable-interval schedules across components of a multiple schedule. We paired one target stimulus with a richer reinforced alternative and the other with a leaner alternative. Furthermore, we varied reinforcement rates for the paired alternatives to assess the effects of manipulating relative conditioned value on preference and resistance to disruption by presession feeding, intercomponent food, and extinction. We replicated the opposing relation between preference and resistance to disruption but varying reinforcement rates for the paired alternatives did not systematically affect preference or resistance to disruption beyond levels observed in our initial condition. Importantly, we found that only preference between the target stimuli was related to relative baseline response rates in the presence of those stimuli. These findings suggest that preference during extinction probes might reveal more about baseline response rates between concurrently available alternatives than relative conditioned value. Resistance to disruption, conversely, appears to better reflect conditioned value because it is less confounded with baseline response rates and is a function of all sources of reinforcement obtained in the presence of a stimulus context. © Society for the Experimental Analysis of Behavior.

  15. Laser damage resistance of RbTiOPO(4): evidence of polarization dependent anisotropy.

    Science.gov (United States)

    Wagner, F R; Hildenbrand, A; Natoli, J Y; Commandré, M; Théodore, F; Albrecht, H

    2007-10-17

    Nanosecond-laser induced damage of RbTiOPO(4) crystals (RTP) has been studied at 1064 nm as a function of propagation direction and polarization orientation. A significant difference in the Laser Induced Damage Threshold (LIDT) was observed for x-cut and y-cut crystals in Pockels cell configuration, where the light propagation direction is along the x and y axes of the crystal respectively. In Pockels cell configuration the polarization is oriented at 45? with respect to the z-axis of the crystal. Experiments with the polarization oriented parallel to the principal axes of the crystal pointed out the importance of the polarization direction for the LIDT whereas the propagation direction did not significantly influence the LIDT. Comparison of the experimental data with a simple model reveals the influence of frequency doubling on the LIDT in Pockels cell configuration. In the case of the y-cut Pockels cell, the generation of frequency doubled light causes an LIDT below the LIDT of x and z-polarized light at the fundamental wavelength.

  16. Phosphorene/rhenium disulfide heterojunction-based negative differential resistance device for multi-valued logic

    Science.gov (United States)

    Shim, Jaewoo; Oh, Seyong; Kang, Dong-Ho; Jo, Seo-Hyeon; Ali, Muhammad Hasnain; Choi, Woo-Young; Heo, Keun; Jeon, Jaeho; Lee, Sungjoo; Kim, Minwoo; Song, Young Jae; Park, Jin-Hong

    2016-01-01

    Recently, negative differential resistance devices have attracted considerable attention due to their folded current–voltage characteristic, which presents multiple threshold voltage values. Because of this remarkable property, studies associated with the negative differential resistance devices have been explored for realizing multi-valued logic applications. Here we demonstrate a negative differential resistance device based on a phosphorene/rhenium disulfide (BP/ReS2) heterojunction that is formed by type-III broken-gap band alignment, showing high peak-to-valley current ratio values of 4.2 and 6.9 at room temperature and 180 K, respectively. Also, the carrier transport mechanism of the BP/ReS2 negative differential resistance device is investigated in detail by analysing the tunnelling and diffusion currents at various temperatures with the proposed analytic negative differential resistance device model. Finally, we demonstrate a ternary inverter as a multi-valued logic application. This study of a two-dimensional material heterojunction is a step forward toward future multi-valued logic device research. PMID:27819264

  17. Phosphorene/rhenium disulfide heterojunction-based negative differential resistance device for multi-valued logic

    Science.gov (United States)

    Shim, Jaewoo; Oh, Seyong; Kang, Dong-Ho; Jo, Seo-Hyeon; Ali, Muhammad Hasnain; Choi, Woo-Young; Heo, Keun; Jeon, Jaeho; Lee, Sungjoo; Kim, Minwoo; Song, Young Jae; Park, Jin-Hong

    2016-11-01

    Recently, negative differential resistance devices have attracted considerable attention due to their folded current-voltage characteristic, which presents multiple threshold voltage values. Because of this remarkable property, studies associated with the negative differential resistance devices have been explored for realizing multi-valued logic applications. Here we demonstrate a negative differential resistance device based on a phosphorene/rhenium disulfide (BP/ReS2) heterojunction that is formed by type-III broken-gap band alignment, showing high peak-to-valley current ratio values of 4.2 and 6.9 at room temperature and 180 K, respectively. Also, the carrier transport mechanism of the BP/ReS2 negative differential resistance device is investigated in detail by analysing the tunnelling and diffusion currents at various temperatures with the proposed analytic negative differential resistance device model. Finally, we demonstrate a ternary inverter as a multi-valued logic application. This study of a two-dimensional material heterojunction is a step forward toward future multi-valued logic device research.

  18. Direct current (DC) resistivity and induced polarization (IP) monitoring of active layer dynamics at high temporal resolution

    DEFF Research Database (Denmark)

    Doetsch, Joseph; Ingeman-Nielsen, Thomas; Christiansen, Anders V.

    2015-01-01

    With permafrost thawing and changes in active layer dynamics induced by climate change, interactions between biogeochemical and thermal processes in the ground are of great importance. Here, active layer dynamics have been monitored using direct current (DC) resistivity and induced polarization (IP...... and subsurface temperatures supplemented the DC-IP measurements. A time-lapse DC-IP monitoring system has been acquiring at least six datasets per day on a 42-electrode profile with 0.5. m electrode spacing since July 2013. Remote control of the data acquisition system enables interactive adaptation...

  19. Study of true-remanent polarization using remanent hysteresis task and resistive leakage analysis in ferroelectric 0.64Pb(Mg1/3Nb2/3)O3-0.36PbTiO3 ceramics

    Science.gov (United States)

    Joseph, Abhilash J.; Kumar, Binay

    2018-03-01

    The conventionally reported value of remanent polarization (Pr) contains contribution from non-remanent components which are not usable for memory device applications. This report presents techniques which extract the true-remanent (intrinsic) component of polarization after eliminating the non-remanent component in ferroelectric ceramics. For this, "remanent hysteresis task" and "positive-up-negative-down technique" were performed which utilized the switchable properties of polarizations to nullify the contributions from the non-remanent (non-switchable) components. The report also addresses the time-dependent leakage behavior of the ceramics focusing on the presence of resistive leakage (a time-dependent parameter) present in the ceramics. The techniques presented here are especially useful for polycrystalline ceramics where leakage current leads to an erroneous estimation of Pr.

  20. Dwindling the resistance value of PEDOT:PSS – coated on fabric yarns

    Energy Technology Data Exchange (ETDEWEB)

    Amba Sankar, K.N., E-mail: amb@psgias.ac.in; Kallol, Mohanta [Nanotechnology Research, Innovation & Incubation Centre, Organic Solar cell lab, PSG Institute of Advanced Studies, Coimbatore – 641 004, Tamilnadu (India)

    2016-05-23

    Herein we describe by dip coating method to transform typical fabric yarn to conductive fiber. Different types of yarns have been used to coat from a known conductive polymer, Poly (3,4ethylenedioxythiophene) Poly (styrene sulfonic acid). We have optimized the method to have lesser resistance of the conductive yarns. The minimum resistance achieved has a value of 77 Ω/cm. This value is not high as metals but could be comparable to that of metal oxides or semiconducting materials. However, flexibility of yarns and feeling of fabric combining with the conductivity developed in this process is suitable for wearable electronics and also as gas sensors, electromagnetic shielding.

  1. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal—Contribution of Fouling and Concentration Polarization to Filtration Resistance

    Directory of Open Access Journals (Sweden)

    Joerg Winter

    2017-07-01

    Full Text Available Nanofiltration (NF and tight ultrafiltration (tight UF membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP and fouling to the increase in resistance during filtration of natural organic matter (NOM with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM, the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM, the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  2. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal-Contribution of Fouling and Concentration Polarization to Filtration Resistance.

    Science.gov (United States)

    Winter, Joerg; Barbeau, Benoit; Bérubé, Pierre

    2017-07-02

    Nanofiltration (NF) and tight ultrafiltration (tight UF) membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP) and fouling to the increase in resistance during filtration of natural organic matter (NOM) with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs) of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM), the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM), the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  3. Effect of Contact Pressure on the Resistance Contact Value and Temperature Changes in Copper Busbar Connection

    Directory of Open Access Journals (Sweden)

    Agus Risdiyanto

    2012-12-01

    Full Text Available This paper discussed the influence of tightness or contacts pressure on copper busbar joints to determine changes in the value of the initial contact resistance and the maximum temperature at the joint due to high current load. The test sample was copper busbar 3 x 30 mm with configuration of bolted overlapping joint. Increasing contact pressure at the joint was measured to find out its effect on the value of contact resistance. The applied pressure was 6 to 36 MPa. Procedure of contact resistance measurement refer to the ASTM B539 standard using four-wire method. The sample subsequently loaded with the current of 350 A for 60 minutes and the maximum temperature at the joint was measured. The result showed that increasing contact pressure at the busbar joint will reduce the contact resistance and maximum temperature. The increase of contact pressure from 6 to 30 MPa causes decreasing contact resistance from 16 μΩ to 11 μΩ. Further increasing of contact pressure more than 30 MPa did not affect the contact resistance significantly. The lowest temperatur of busbar joint of 54°C was reached at a contact pressure of 36 Mpa.

  4. Resistance to consumption and Veganism: A Study about Motivations, Values, and Feelings

    OpenAIRE

    Moreira, Isabela Perez Campos; Acevedo, Claudia Rosa

    2015-01-01

    The purpose of this research is to study resistance to consumption as a recent phenomenon designed to bring about changes in societal values and consumptio habits. Specifically the objective of this paper is to comprehend the way in which anti-consumption behavior relates to Veganism, analyze factors that motivate its practice, and record values and feelings associated with the acceptance of the movement.This study utilized the ethnographic method of collection and analysis of data through pa...

  5. 1-D DC Resistivity Inversion Using Singular Value Decomposition and Levenberg-Marquardt’s Inversion Schemes

    Science.gov (United States)

    Heriyanto, M.; Srigutomo, W.

    2017-07-01

    Exploration of natural or energy resources requires geophysical survey to determine the subsurface structure, such as DC resistivity method. In this research, field and synthetic data were used using Schlumberger configuration. One-dimensional (1-D) DC resistivity inversion was carried out using Singular Value Decomposition (SVD) and Levenberg-Marquardt (LM) techniques to obtain layered resistivity structure. We have developed software to perform both inversion methods accompanied by a user-friendly interface. Both of the methods were compared one another to determine the number of iteration, robust to noise, elapsed time of computation, and inversion results. SVD inversion generated faster process and better results than LM did. The inversion showed both of these methods were appropriate to interpret subsurface resistivity structure.

  6. Dispositional resistance to change: Measurement equivalence and the link to personal values across 17 nations

    Czech Academy of Sciences Publication Activity Database

    Oreg, S.; Bayazit, M.; Vakola, M.; Arciniega, L.; Armenakis, A.; Barkauskiene, R.; Bozionelos, N.; Ferič, I.; Fujimoto, Y.; Gonzáles, L.; Han, J.; Hetland, H.; Hřebíčková, Martina; Jimmieson, N.; Kordačová, J.; Kotrla Topič, M.; Mitsuhashi, H.; Mlacić, B.; Ohly, S.; Saksvik, I.; Saksvik, P.O.; van Dam, K.

    2008-01-01

    Roč. 93, č. 4 (2008), s. 935-944 ISSN 0021-9010 R&D Projects: GA AV ČR IAA700250702 Institutional research plan: CEZ:AV0Z70250504 Keywords : resistance to change * personal values * measurement equivalence Subject RIV: AN - Psychology Impact factor: 3.769, year: 2008

  7. Analysis of Resistive-Vee Dipole Antennas for Producing Polarization Diversity

    Science.gov (United States)

    2014-08-01

    wooden block and wire is shown in Figure 56. The results for this experiment are shown in Figure 57. The wire target ap- pears as a strong blue on...flat surface, it should have a low co-polarization response and ap- pear red on the false color maps. The wire targets appear very similar with the Kim...radars,” IEEE Transactions on Electromagnetic Compatibility , vol. 36, no. 1, February 1994. [34] M. McFadden, “Analysis of the equiangular spiral antenna

  8. The Behaviour of Laboratory Soil Electrical Resistivity Value under Basic Soil Properties Influences

    International Nuclear Information System (INIS)

    Hazreek, Z A M; Aziman, M; Azhar, A T S; Chitral, W D; Fauziah, A; Rosli, S

    2015-01-01

    Electrical resistivity method (ERM) was a popular indirect geophysical tools adopted in engineering, environmental and archaeological studies. In the past, results of the electrical resistivity value (ERV) were always subjected to a long discussion and debate among the related parties such as an engineers, geophysicists and geologists due to its lack of clarification and evidences in quantitative point of view. Most of the results produced in the past was always been justified using qualitative ways which difficult to be accept by certain parties. In order to reduce the knowledge gap between those parties, this study has performed a laboratory experiment of soil box resistivity test which supported by an additional basic geotechnical test as referred to particle size distribution test (d), moisture content test (w), density test (ρ bulk ) and Atterberg limit test (LL, PL and PI). The test was performed to establish a series of electrical resistivity value with different quantity of water content for Clayey SILT and Silty SAND soil. It was found that the ERV of Silty SAND (600 - 7300 Ωm) was higher than Clayey SILT (13 - 7700 Ωm) due to the different quantity of basic soil properties value obtained from the basic geotechnical test. This study was successfully demonstrated that the fluctuation of ERV has greatly influenced by the variations of the soil physical properties (d, w, ρ bulk , LL, PL and PI). Hence, the confidence level of ERV interpretation will be increasingly meaningful since it able to be proved by others parameter generated by laboratory direct test

  9. The Energetic Value of Land-Based Foods in Western Hudson Bay and Their Potential to Alleviate Energy Deficits of Starving Adult Male Polar Bears.

    Science.gov (United States)

    Gormezano, Linda J; Rockwell, Robert F

    2015-01-01

    Climate change is predicted to expand the ice-free season in western Hudson Bay and when it grows to 180 days, 28-48% of adult male polar bears are projected to starve unless nutritional deficits can be offset by foods consumed on land. We updated a dynamic energy budget model developed by Molnar et al. to allow influx of additional energy from novel terrestrial foods (lesser snow geese, eggs, caribou) that polar bears currently consume as part of a mixed diet while on land. We calculated the units of each prey, alone and in combination, needed to alleviate these lethal energy deficits under conditions of resting or limited movement (2 km d-1) prior to starvation. We further considered the total energy available from each sex and age class of each animal prey over the period they would overlap land-bound polar bears and calculated the maximum number of starving adult males that could be sustained on each food during the ice-free season. Our results suggest that the net energy from land-based food, after subtracting costs of limited movement to obtain it, could eliminate all projected nutritional deficits of starving adult male polar bears and likely other demographic groups as well. The hunting tactics employed, success rates as well as behavior and abundance of each prey will determine the realized energetic values for individual polar bears. Although climate change may cause a phenological mismatch between polar bears and their historical ice-based prey, it may simultaneously yield a new match with certain land-based foods. If polar bears can transition their foraging behavior to effectively exploit these resources, predictions for starvation-related mortality may be overestimated for western Hudson Bay. We also discuss potential complications with stable-carbon isotope studies to evaluate utilization of land-based foods by polar bears including metabolic effects of capture-related stress and consuming a mixed diet.

  10. The Energetic Value of Land-Based Foods in Western Hudson Bay and Their Potential to Alleviate Energy Deficits of Starving Adult Male Polar Bears.

    Directory of Open Access Journals (Sweden)

    Linda J Gormezano

    Full Text Available Climate change is predicted to expand the ice-free season in western Hudson Bay and when it grows to 180 days, 28-48% of adult male polar bears are projected to starve unless nutritional deficits can be offset by foods consumed on land. We updated a dynamic energy budget model developed by Molnar et al. to allow influx of additional energy from novel terrestrial foods (lesser snow geese, eggs, caribou that polar bears currently consume as part of a mixed diet while on land. We calculated the units of each prey, alone and in combination, needed to alleviate these lethal energy deficits under conditions of resting or limited movement (2 km d-1 prior to starvation. We further considered the total energy available from each sex and age class of each animal prey over the period they would overlap land-bound polar bears and calculated the maximum number of starving adult males that could be sustained on each food during the ice-free season. Our results suggest that the net energy from land-based food, after subtracting costs of limited movement to obtain it, could eliminate all projected nutritional deficits of starving adult male polar bears and likely other demographic groups as well. The hunting tactics employed, success rates as well as behavior and abundance of each prey will determine the realized energetic values for individual polar bears. Although climate change may cause a phenological mismatch between polar bears and their historical ice-based prey, it may simultaneously yield a new match with certain land-based foods. If polar bears can transition their foraging behavior to effectively exploit these resources, predictions for starvation-related mortality may be overestimated for western Hudson Bay. We also discuss potential complications with stable-carbon isotope studies to evaluate utilization of land-based foods by polar bears including metabolic effects of capture-related stress and consuming a mixed diet.

  11. Host antitumor resistance improved by the macrophage polarization in a chimera model of patients with HCC.

    Science.gov (United States)

    Asai, Akira; Tsuchimoto, Yusuke; Ohama, Hideko; Fukunishi, Shinya; Tsuda, Yasuhiro; Kobayashi, Makiko; Higuchi, Kazuhide; Suzuki, Fujio

    2017-01-01

    Despite major advances in curative and palliative approaches, hepatocellular carcinoma (HCC) is still the third leading cause of cancer-related death worldwide. M1 macrophages (Mϕ) play a key role in host antitumor defenses in HCC. In our study, CD14 + cells were isolated from the peripheral blood of four groups of HCC patients (group-1, patients with stage 0 HCC; group-2, patients with stage A HCC; group-3, patients with stage B HCC; and group-4, patients with stage C HCC) and characterized phenotypically. Then, CD14 + cells from group-2 and group-3 HCC patients were induced to polarize and tested for their antitumor abilities in a chimera model of HCC patients. Human HCCs (HepG2 solid tumors) grew in a chimera model of group-3 patients (group-3 HCC chimeras) but not in a chimera model of group-2 patients (group-2 HCC chimeras). In response to HCC antigens, the majority of CD14 + cells from group-2 patients (group-2 CD14 + cells) switched to the M1 phenotype (IL-12 + IL-10 - iNOS + cells), whereas the majority of CD14 + cells from group-3 patients (group-3 CD14 + cells) did not switch to the M1 phenotype and continued to express M2b phenotypic properties (IL-12 - IL-10 + CCL1 + iNOS - cells). Group-3 CD14 + cells showed M1Mϕ polarization after treatment with CCL1 antisense oligodeoxynucleotide (ODN). Therefore, our study indicates that anti-HCC defenses of group-3 HCC chimeras are improved after CCL1 antisense ODN treatment.

  12. Determination of Soil Moisture Content using Laboratory Experimental and Field Electrical Resistivity Values

    Science.gov (United States)

    Hazreek, Z. A. M.; Rosli, S.; Fauziah, A.; Wijeyesekera, D. C.; Ashraf, M. I. M.; Faizal, T. B. M.; Kamarudin, A. F.; Rais, Y.; Dan, M. F. Md; Azhar, A. T. S.; Hafiz, Z. M.

    2018-04-01

    The efficiency of civil engineering structure require comprehensive geotechnical data obtained from site investigation. In the past, conventional site investigation was heavily related to drilling techniques thus suffer from several limitations such as time consuming, expensive and limited data collection. Consequently, this study presents determination of soil moisture content using laboratory experimental and field electrical resistivity values (ERV). Field and laboratory electrical resistivity (ER) test were performed using ABEM SAS4000 and Nilsson400 soil resistance meter. Soil sample used for resistivity test was tested for characterization test specifically on particle size distribution and moisture content test according to BS1377 (1990). Field ER data was processed using RES2DINV software while laboratory ER data was analyzed using SPSS and Excel software. Correlation of ERV and moisture content shows some medium relationship due to its r = 0.506. Moreover, coefficient of determination, R2 analyzed has demonstrate that the statistical correlation obtain was very good due to its R2 value of 0.9382. In order to determine soil moisture content based on statistical correlation (w = 110.68ρ-0.347), correction factor, C was established through laboratory and field ERV given as 19.27. Finally, this study has shown that soil basic geotechnical properties with particular reference to water content was applicably determined using integration of laboratory and field ERV data analysis thus able to compliment conventional approach due to its economic, fast and wider data coverage.

  13. Prediction of WBGT-based clothing adjustment values from evaporative resistance.

    Science.gov (United States)

    Bernard, Thomas E; Ashley, Candi D; Garzon, Ximena P; Kim, Jung-Hyun; Coca, Aitor

    2017-12-07

    Wet bulb globe temperature (WBGT) index is used by many professionals in combination with metabolic rate and clothing adjustments to assess whether a heat stress exposure is sustainable. The progressive heat stress protocol is a systematic method to prescribe a clothing adjustment value (CAV) from human wear trials, and it also provides an estimate of apparent total evaporative resistance (R e,T,a ). It is clear that there is a direct relationship between the two descriptors of clothing thermal effects with diminishing increases in CAV at high R e,T,a . There were data to suggest an interaction of CAV and R e,T,a with relative humidity at high evaporative resistance. Because human trials are expensive, manikin data can reduce the cost by considering the static total evaporative resistance (R e,T,s ). In fact, as the static evaporative resistance increases, the CAV increases in a similar fashion as R e,T,a . While the results look promising that R e,T,s can predict CAV, some validation remains, especially for high evaporative resistance. The data only supports air velocities near 0.5 m/s.

  14. 3D inversion of magnetic and electrical resistivity-induced polarization data for an epithermal Au-Ag and underlying porphyry deposit: A case study from British Columbia, Canada

    Science.gov (United States)

    Abbassi, B.; Huebert, J.; Liu, L.; Lee, B.; Cheng, L.; Richards, J. P.; Unsworth, M. J.; Oldenburg, D.

    2013-12-01

    The Newton property is an epithermal Au-Ag deposit containing precious metals in association with disseminated sulfide minerals such as pyrite. This type of deposit often shows variable geological patterns, so it is important to find fast and cost-efficient methods for their exploration. Aeromagnetic surveys and ground electrical resistivity-induced polarization methods were applied over the Newton property. From preliminary 3D inversion of ZTEM and aeromagnetic data, and joint 3D inversion of electrical resistivity-induced polarization data, we show that low-resistivity and high-chargeability regions are signatures of disseminated sulfide mineralization. Potassic alteration, characterized by hydrothermal biotite (now mostly chloritized) and magnetite is also present locally, and may be related to underlying porphyry-type mineralization. This type of alteration can be identified from its magnetic signature, but the occurrence of other magnetic formations in the deposit area made interpretations of magnetic data difficult. We show that filtering geological noises related to background magnetic anomalies is an essential step in focusing on potassic alteration zones. We used electrical resistivity and induced polarization chargeability models to remove the signals of barren magnetic zones to focus on the susceptibilities pertaining to deep potassic alterations. In order to test the credibility of these interpretations, extensive petrophysical measurements (magnetic susceptibility, electrical resistivity, and gamma ray spectra) were collected on drill-core samples. We show that potassic alteration can also be characterized accurately from high levels of potassium to thorium ratio (K/Th) in gamma ray spectrometric measurements, and that this correlation is stronger than the magnetic signal (likely because hydrothermal magnetite is variable in abundance). Therefore, we focused on magnetic susceptibility values correlated with high K/Th ratios in order to reduce the

  15. Vitamins A and E in liver, kidney, and whole blood of East Greenland polar bears sampled 1994–2008: reference values and temporal trends

    DEFF Research Database (Denmark)

    Bechshoft, T.; Sonne, C.; Jakobsen, Jette

    2015-01-01

    that POPs could be disrupting polar bear vitamin status. However, while the observed temporal increases in vitamin concentrations were likely POP related, the question remains as to whether they stem from influence of contaminants only or also, e.g., changes in prey species. Further studies are needed......Vitamins A (retinol) and E (α-tocopherol) are dietary vitamins, essential for, e.g., growth and development, reproduction, and immune function. Persistent organic pollutants (POPs) have been found to be related to vitamin A and E metabolism. However, few investigations have been published...... on this health issue in polar bears (Ursus maritimus). The aim of this study was thus to provide reference values for concentrations of vitamin A in liver, kidney cortex, and whole blood and vitamin E in kidney cortex and whole blood from 166 East Greenland polar bears, as well as to assess the relationship...

  16. Hyperhomocysteinemia Promotes Insulin Resistance and Adipose Tissue Inflammation in PCOS Mice Through Modulating M2 Macrophage Polarization via Estrogen Suppression.

    Science.gov (United States)

    Qi, Xinyu; Zhang, Bochun; Zhao, Yue; Li, Rong; Chang, Hsun-Ming; Pang, Yanli; Qiao, Jie

    2017-05-01

    It has been shown that serum homocysteine (Hcy) levels are higher in women with polycystic ovary syndrome (PCOS). However, the specific role of hyperhomocysteinemia (HHcy) in the development of PCOS has never been reported. Adipose tissue inflammation is featured by the infiltration of macrophages, which plays a critical role in the pathogenesis of glucose and insulin intolerance. In this study, C57BL/6 mice were treated with dehydroepiandrosterone (DHEA) and/or a high methionine diet to induce PCOS and HHcy mice models. We showed that DHEA induced a PCOS-like phenotypes, irregular estrous cycles, weight gain, abnormal sex hormone production, glucose and insulin resistance, and polycystic ovaries. HHcy further intensified the effects DHEA on the metabolic, endocrinal, hormonal, and morphological changes in PCOS-like mice. In addition, HHcy attenuated the DHEA-induced increase in serum estrogen levels in mice. Furthermore, HHcy may exacerbate the insulin resistance in PCOS-like mice, most likely through modulating the macrophage M1/M2 polarization pathways via the suppression of estrogen. Most important, our clinical data showed that there were increases in serum Hcy levels in patients with PCOS. These findings deepen our understanding of the pathological roles of HHcy in the development of PCOS and provide a promising target for PCOS therapy in clinical application. Copyright © 2017 Endocrine Society.

  17. Economic values of body weight, reproduction and parasite resistance traits for a Creole goat breeding goal.

    Science.gov (United States)

    Gunia, M; Mandonnet, N; Arquet, R; Alexandre, G; Gourdine, J-L; Naves, M; Angeon, V; Phocas, F

    2013-01-01

    A specific breeding goal definition was developed for Creole goats in Guadeloupe. This local breed is used for meat production. To ensure a balanced selection outcome, the breeding objective included two production traits, live weight (BW11) and dressing percentage (DP) at 11 months (the mating or selling age), one reproduction trait, fertility (FER), and two traits to assess animal response to parasite infection: packed cell volume (PCV), a resilience trait, and faecal worm eggs count (FEC), a resistance trait. A deterministic bio-economic model was developed to calculate the economic values based on the description of the profit of a Guadeloupean goat farm. The farm income came from the sale of animals for meat or as reproducers. The main costs were feeding and treatments against gastro-intestinal parasites. The economic values were 7.69€ per kg for BW11, 1.38€ per % for FER, 3.53€ per % for DP and 3 × 10(-4)€ per % for PCV. The economic value for FEC was derived by comparing the expected profit and average FEC in a normal situation and in an extreme situation where parasites had developed resistance to anthelmintics. This method yielded a maximum weighting for FEC, which was -18.85€ per log(eggs per gram). Alternative scenarios were tested to assess the robustness of the economic values to variations in the economic and environmental context. The economic values of PCV and DP were the most stable. Issues involved in paving the way for selective breeding on resistance or resilience to parasites are discussed.

  18. Geophysical modeling in gold deposit through DC Resistivity and Induced Polarization methods

    Directory of Open Access Journals (Sweden)

    César Augusto Moreira

    Full Text Available Abstract Ore mining fundamentally depends on the definition of its tenor and volume, something extremely complex in disseminated mineralization, as in the case of certain types of deposits of gold and sulfites. This article proposes the use of electrical tomography for definition of a geophysical signature in terms of electrical resistivity and chargeability, in an outcrop of mineralized quartz lode at the end of an inactive gold mine. One of the targets was to analyze the continuity of the mineralized body, the occurrence of new outcrops and the applicability of the method as an auxiliary tool in mineral extraction. Three parallel lines of electrical tomography in a dipole-dipole arrangement, being orthogonal to the orientation of the gold lode, were installed in an area outside the mine. The results allowed the geophysical characterization of the mineralized zone by high resistivity (above 1000Ω.m and high chargeability (above 30mV/V. The results of the 2D inversion models were interpolated in 3D visualization models, which allowed definition of the contour surfaces for the physical parameters measured, and the morphological pattern modeling of the mineralization. The data reveal the existence of a new lode in subsurface, localized 30m to the south of the lode outcrop. The versatility of the acquisition and data processing indicate the application potential of electrical tomography as a criterion for sampling and tenor definition in ore extraction activities, since it is objective and low cost.

  19. Sensitivity, specificity and predictive value of modified assays for activated protein C resistance in children.

    Science.gov (United States)

    Brandt, G; Gruppo, R; Glueck, C J; Stroop, D; Becker, A; Pillow, A; Wang, P

    1998-03-01

    Very little data is available assessing the clinical utility of coagulation-based APC resistance assays compared to DNA-based analysis for the factor V Leiden mutation in children. Therefore, the clinical utility of four aPTT-based assays for APC resistance was evaluated in 169 children, ages 3 months through 16 years. The prevalence of the Arg506 to Gln mutation was 7/169 (4.1%). Using cutoff points derived from the normal PCR-screened population (n = 162), two assays for APC resistance (APC-SR and n-APC-SR) gave poor concordance with the PCR assay (sensitivity 29% and 57%, respectively). Two modified assays (FDAPC-SR and n-FDAPC-SR), in which patient plasma was prediluted 1:5 in factor V deficient plasma, gave excellent concordance (sensitivity 100%). The predictive value of a positive test was 0.25, 0.44, 1.00 and 0.88 for the APC-SR, n-APC-SR, FDAPC-SR and n-FDAPC-SR, respectively. The FDAPC-SR and n-FDAPC-SR tests gave excellent discrimination using cutoff values derived from the total population (n = 169) without regard to previous PCR screening results.

  20. [Study on the corrosion resistance of Cr ahoy in the artificial saliva with different pH value].

    Science.gov (United States)

    Su, Run-Gang; Li, Chun-Hua; Qian, Ye

    2010-02-01

    To study the effect on the corrosion resistance of Cr alloy in the artificial saliva with different pH value in vitro. Compared to Ti alloy, electrochemical technique was used to measure the electric potential of corrosion (E(corr)), current density of corrosion (I(corr)) Cr alloy in the artificial saliva with different pH value. The corrosion and corrosion resistance mechanism on Cr alloy in the artificial saliva with different pH value had been investigated by the EIS curves. The corrosion resistance of Co-Cr alloy was better than Ti alloy. The value of I(corr) was lower and the value of R(p) was larger than Ti alloy. The corrosion resistance of Ni-Cr alloy was worse than Ti alloy. The value of I(corr) was larger and the value of R(p) was lower than Ti alloy. The pH value in the artificial saliva was decreased, the I(corr) value of three types of alloy increased, the R(p) value of three types of alloy decreased. But the changes of Co-Cr alloy was smaller than that of Ti alloy or Ni-Cr alloy. The corrosion resistance of Co-Cr alloy was superior to that of Ni-Cr alloy and Ti alloy. In the acid artificial saliva, the corrosion resistance of three types of alloy descended evidently.

  1. Low temporal variation in the intact polar lipid composition of North Sea coastal marine water reveals limited chemotaxonomic value

    NARCIS (Netherlands)

    Brandsma, J.; Hopmans, E.C.; Philippart, C.J.M.; Veldhuis, M.J.W.; Schouten, S.; Sinninghe Damsté, J.S.S.

    2012-01-01

    Temporal variations in the abundance and composition of intact polar lipids (IPLs) in North Sea coastal marine water were assessed over a one-year seasonal cycle, and compared with environmental parameters and the microbial community composition. Sulfoquinovosyldiacylglycerol (SQDG) was the most

  2. Defect-Resistant Radiative Performance of m-Plane Immiscible Al1-xInxN Epitaxial Nanostructures for Deep-Ultraviolet and Visible Polarized Light Emitters.

    Science.gov (United States)

    Chichibu, Shigefusa F; Kojima, Kazunobu; Uedono, Akira; Sato, Yoshitaka

    2017-02-01

    Planar vacuum-fluorescent-display devices emitting polarized UV-C, blue, and green light are demonstrated using immiscible Al 1- x In x N nanostructures grown in nonpolar m-directions. Despite the presence of high concentration of nonradiative recombination centers, the Al 1- x In x N nanostructures emit polarized light with the luminescence lifetimes of 22-32 ps at 300 K. This defect-resistant radiative performance suggests supernormal localized characteristics of electron-hole pairs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Prediction of Skid Resistance Value of Glass Fiber-Reinforced Tiling Materials

    Directory of Open Access Journals (Sweden)

    Sadik Alper Yildizel

    2017-01-01

    Full Text Available This research focuses on the use of adaptive artificial neural network system for evaluating the skid resistance value (British Pendulum Number; BPN of the glass fiber-reinforced tiling materials. During the creation of the neural model, four main factors were considered: fiber, calcium carbonate content, sand blasting, and polishing properties of the specimens. The model was trained, tested, and compared with the on-site test results. As per the comparison of the outcomes of the study, the analysis and on-site test results showed that there is a great potential for the prediction of BPN of glass fiber-reinforced tiling materials by using developed neural system.

  4. The value of second polar body detection 4 hours after insemination and early rescue ICSI in preventing complete fertilisation failure in patients with borderline semen.

    Science.gov (United States)

    Jin, Haixia; Shu, Yimin; Dai, Shanjun; Peng, Zhaofeng; Shi, Senlin; Sun, Yingpu

    2014-01-01

    In this study we evaluated the value of short-time insemination and early rescue intra-cytoplasmic sperm injection (ICSI) in preventing the occurrence of complete fertilisation failure for mild or moderate male infertility patients. A total of 866 couples with borderline semen who underwent in vitro fertilisation treatment in 2010 were included. Regular insemination was performed between January and June of 2010 and short-term insemination was performed from July through December 2010, where, as early as 4h after insemination, oocytes were denuded from cumulus cells and extrusion of the second polar body was evaluated. Of the 4153 mature oocytes with a detectable second polar body 4 h after insemination, 3874 (93.3%) showed signs of fertilisation on Day 1. Where no second polar body was present in any of the retrieved oocytes for a given patient, rescue ICSI was performed immediately. Similar rates of normal fertilisation and percentage of good-quality embryos were obtained between early rescue ICSI and regular ICSI. Clinical pregnancy occurred in 16 of 43 patients (37.2%) receiving early rescue ICSI. Our results showed early rescue ICSI in combination with evaluation of the second polar body 4 h following insemination is an effective method to prevent complete fertilisation failure for patients with mild or moderate male infertility.

  5. Theoretical investigation into negative differential resistance characteristics of resonant tunneling diodes based on lattice-matched and polarization-matched AlInN/GaN heterostructures

    Science.gov (United States)

    Rong, Taotao; Yang, Lin-An; Yang, Lin; Hao, Yue

    2018-01-01

    In this work, we report an investigation of resonant tunneling diodes (RTDs) with lattice-matched and polarization-matched AlInN/GaN heterostructures using the numerical simulation. Compared with the lattice-matched AlInN/GaN RTDs, the RTDs based on polarization-matched AlInN/GaN hetero-structures exhibit symmetrical conduction band profiles due to eliminating the polarization charge discontinuity, which achieve the equivalence of double barrier transmission coefficients, thereby the relatively high driving current, the high symmetry of current density, and the high peak-to-valley current ratio (PVCR) under the condition of the positive and the negative sweeping voltages. Simulations show that the peak current density approaches 1.2 × 107 A/cm2 at the bias voltage of 0.72 V and the PVCR approaches 1.37 at both sweeping voltages. It also shows that under the condition of the same shallow energy level, when the trap density reaches 1 × 1019 cm-3, the polarization-matched RTDs still have acceptable negative differential resistance (NDR) characteristics, while the NDR characteristics of lattice-matched RTDs become irregular. After introducing the deeper energy level of 1 eV into the polarization-matched and lattice-matched RTDs, 60 scans are performed under the same trap density. Simulation results show that the degradation of the polarization-matched RTDs is 22%, while lattice-matched RTDs have a degradation of 55%. It can be found that the polarization-matched RTDs have a greater defect tolerance than the lattice-matched RTDs, which is beneficial to the available manufacture of actual terahertz RTD devices.

  6. SGLT2 Inhibition by Empagliflozin Promotes Fat Utilization and Browning and Attenuates Inflammation and Insulin Resistance by Polarizing M2 Macrophages in Diet-induced Obese Mice.

    Science.gov (United States)

    Xu, Liang; Nagata, Naoto; Nagashimada, Mayumi; Zhuge, Fen; Ni, Yinhua; Chen, Guanliang; Mayoux, Eric; Kaneko, Shuichi; Ota, Tsuguhito

    2017-06-01

    Sodium-glucose cotransporter (SGLT) 2 inhibitors increase urinary glucose excretion (UGE), leading to blood glucose reductions and weight loss. However, the impacts of SGLT2 inhibition on energy homeostasis and obesity-induced insulin resistance are less well known. Here, we show that empagliflozin, a SGLT2 inhibitor, enhanced energy expenditure and attenuated inflammation and insulin resistance in high-fat-diet-induced obese (DIO) mice. C57BL/6J mice were pair-fed a high-fat diet (HFD) or a HFD with empagliflozin for 16weeks. Empagliflozin administration increased UGE in the DIO mice, whereas it suppressed HFD-induced weight gain, insulin resistance, and hepatic steatosis. Moreover, empagliflozin shifted energy metabolism towards fat utilization, elevated AMP-activated protein kinase and acetyl-CoA carbolxylase phosphorylation in skeletal muscle, and increased hepatic and plasma fibroblast growth factor 21 levels. Importantly, empagliflozin increased energy expenditure, heat production, and the expression of uncoupling protein 1 in brown fat and in inguinal and epididymal white adipose tissue (WAT). Furthermore, empagliflozin reduced M1-polarized macrophage accumulation while inducing the anti-inflammatory M2 phenotype of macrophages within WAT and liver, lowering plasma TNFα levels and attenuating obesity-related chronic inflammation. Thus, empagliflozin suppressed weight gain by enhancing fat utilization and browning and attenuated obesity-induced inflammation and insulin resistance by polarizing M2 macrophages in WAT and liver. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  7. SGLT2 Inhibition by Empagliflozin Promotes Fat Utilization and Browning and Attenuates Inflammation and Insulin Resistance by Polarizing M2 Macrophages in Diet-induced Obese Mice

    Directory of Open Access Journals (Sweden)

    Liang Xu

    2017-06-01

    Full Text Available Sodium-glucose cotransporter (SGLT 2 inhibitors increase urinary glucose excretion (UGE, leading to blood glucose reductions and weight loss. However, the impacts of SGLT2 inhibition on energy homeostasis and obesity-induced insulin resistance are less well known. Here, we show that empagliflozin, a SGLT2 inhibitor, enhanced energy expenditure and attenuated inflammation and insulin resistance in high-fat-diet-induced obese (DIO mice. C57BL/6J mice were pair-fed a high-fat diet (HFD or a HFD with empagliflozin for 16 weeks. Empagliflozin administration increased UGE in the DIO mice, whereas it suppressed HFD-induced weight gain, insulin resistance, and hepatic steatosis. Moreover, empagliflozin shifted energy metabolism towards fat utilization, elevated AMP-activated protein kinase and acetyl-CoA carbolxylase phosphorylation in skeletal muscle, and increased hepatic and plasma fibroblast growth factor 21 levels. Importantly, empagliflozin increased energy expenditure, heat production, and the expression of uncoupling protein 1 in brown fat and in inguinal and epididymal white adipose tissue (WAT. Furthermore, empagliflozin reduced M1-polarized macrophage accumulation while inducing the anti-inflammatory M2 phenotype of macrophages within WAT and liver, lowering plasma TNFα levels and attenuating obesity-related chronic inflammation. Thus, empagliflozin suppressed weight gain by enhancing fat utilization and browning and attenuated obesity-induced inflammation and insulin resistance by polarizing M2 macrophages in WAT and liver.

  8. The value of intrarenal resistive index in patients with liver cirrhosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Rae [Kangbuk Samsung Hospital, Seoul (Korea, Republic of)

    1997-08-01

    To determine whether the value of the intrarenal resistive index(RI) can be used to identify early kidney vasoconstriciton in patients with nonazotemic liver cirrhosis The intrarneal resistive index (RI), kidney and liver function and plasma renin activity were measured in 12 healthy control subjects, 13 cirrhotic patients without ascites and 29 cirrhotic patients with ascites. To evaluate the development of hepatorenal syndrome, patients were followed up for six months. RI was significantly higher in patients with cirrhosis (0.68{+-}0.06) than in healthy subjects (0.59{+-}0.04). In 42 cirrhotic patients, it was significantly higher in those with ascites (0.69{+-}0.05) than in those without ascites (0.64{+-}0.05) and correlated with creatinine clearance. Plasma renin activity was significantly highter in cirrhotic patients with ascites than in those without ascites and healthy subjects (p<0.05). During the six-month follow-up period, kidney dysfunction developed in 16%(7/42) of cirrhotic patiens, and in 37%(6/16) of those with an elevated RI. In contrast, only 4%(1/26) of patients with a normal RI has kidney dysfunction. The measurement of intrarenal resitive index(RI) using duplex Doppler ultrasound is a simple, noninvasive method of detecting even subtle derangements of renal hemodynamics in liver cirrhosis patients;the procedure can be used to identify those who are at higher risk of overt renal failure and to help decide whether a therapeutic approach involving paracentesis, diuretics, or nephrotoxic agents is most appropriate.

  9. Value of Resistive lndex of the lntrascrotal Artery in ScrotaI Inflammatory Disease

    International Nuclear Information System (INIS)

    Jee, Won Hee; Yoon, Yeo Dong; Hwang, Sung Su; Choi, Byung Gil; Son, Kyung Myung; Lee, Sung Yong; Kim, Ki Tae; Shinn, Kyung Sub

    1995-01-01

    This prospective study was designed to investigate the utility of resistive indices(RIs) of intratesticular and epididymal arteries in inflammatory scrotal disease. Gray-scale and color Doppler ultrasonographic images were obtained in 19 consecutive patients of scrotal inflammatory disease from Nov.1993 to Oct. 1994. Eleven cases of epididymitis and 11 of epididymoorchitis(EO) were included. RIs of epididymal and centripetal arteries were calculated in 19 patients and 30 cases of control. All EO and epididymitis cases showed increased color signal at color Doppler ultrasonogram at representative sites. Mean RI of centripetal artery was 0.46±0.06 in EO and 0.66±0.07 in normal control, hence RI in EO was significantly lower than that of normal control(P<0.001). The diagnostic sensitivity was 91% when the value of 0.5 or less is estimated abnormal.Mean RI of centripetal artery was 0.67±0.07 in epididymitis, and was not significantly different from that of normal control(P=0.687). Mean RI of epididymal artery in epididymitis and EO was 0.48±0.12 and resistive index of all patients were below 0.7. Color Doppler can demonstrate the hyperemic response to scrotal inflammatory disease that it can supplement the gray scale finding leading to increased diagnostic confidence. RI of centripetal artery may be confirmative in the diagnosis of inflammatory scrotal inflammatory scrotal diseases when increased color flow on color flow imaging is present

  10. Generalized form of boundary value problems method for material modeled as micro-polar media subjecting to the thermo-mechanical interaction

    Science.gov (United States)

    Zhang, Xiaomin; Zhang, Long; Chu, Zhongxiang; Peng, Song

    2016-09-01

    In this paper, the periodic structure material is modeled as the continuum homogeneous micro-polar media subjecting to thermo-mechanical interaction. Meanwhile, a series of equivalent quantities such as the equivalent stress, couple stress, displacement gradient and torsion tensor were defined by the integral forms of the boundary values of the external surface force, moment, displacement and the angular displacement, and were proved to satisfy the equivalence conditions of virtual work. Based on above works, the displacement boundary value problem was established to deduce the equivalent constitutive equation. Assume the representative volume element is composed of the spatial cross-framework, and applying the boundary value problem of displacement on frame structures, the equivalent elastic coefficients, temperature coefficients of equivalent stress and the temperature gradient coefficients of equivalent couple stress are deduced. In addition, themethod can also be extended to the stress boundary value problem to deduce the equivalent constitutive equation. The calculations indicate that the equivalent result can be obtained from the two kinds of boundary value problems.

  11. Prognostic Value of Pulmonary Vascular Resistance by Magnetic Resonance in Systolic Heart Failure

    Energy Technology Data Exchange (ETDEWEB)

    Fabregat-Andrés, Óscar, E-mail: osfabregat@gmail.com [Departamento de Cardiologia - Hospital General Universitario de Valencia, Valencia (Spain); Fundación para la Investigación - Hospital General Universitario de Valencia, Valencia (Spain); Estornell-Erill, Jordi [Unidad de Imagen Cardiaca - ERESA - Hospital General Universitario de Valencia, Valencia (Spain); Ridocci-Soriano, Francisco [Departamento de Cardiologia - Hospital General Universitario de Valencia, Valencia (Spain); Departamento de Medicina. Universitat de Valencia, Valencia (Spain); Pérez-Boscá, José Leandro [Departamento de Cardiologia - Hospital General Universitario de Valencia, Valencia (Spain); García-González, Pilar [Unidad de Imagen Cardiaca - ERESA - Hospital General Universitario de Valencia, Valencia (Spain); Payá-Serrano, Rafael [Departamento de Cardiologia - Hospital General Universitario de Valencia, Valencia (Spain); Departamento de Medicina. Universitat de Valencia, Valencia (Spain); Morell, Salvador [Departamento de Cardiologia - Hospital General Universitario de Valencia, Valencia (Spain); Cortijo, Julio [Fundación para la Investigación - Hospital General Universitario de Valencia, Valencia (Spain); Departamento de Farmacologia. Universitat de Valencia, Valencia (Spain)

    2016-03-15

    Pulmonary hypertension is associated with poor prognosis in heart failure. However, non-invasive diagnosis is still challenging in clinical practice. We sought to assess the prognostic utility of non-invasive estimation of pulmonary vascular resistances (PVR) by cardiovascular magnetic resonance to predict adverse cardiovascular outcomes in heart failure with reduced ejection fraction (HFrEF). Prospective registry of patients with left ventricular ejection fraction (LVEF) < 40% and recently admitted for decompensated heart failure during three years. PVRwere calculated based on right ventricular ejection fraction and average velocity of the pulmonary artery estimated during cardiac magnetic resonance. Readmission for heart failure and all-cause mortality were considered as adverse events at follow-up. 105 patients (average LVEF 26.0 ±7.7%, ischemic etiology 43%) were included. Patients with adverse events at long-term follow-up had higher values of PVR (6.93 ± 1.9 vs. 4.6 ± 1.7estimated Wood Units (eWu), p < 0.001). In multivariate Cox regression analysis, PVR ≥ 5 eWu(cutoff value according to ROC curve) was independently associated with increased risk of adverse events at 9 months follow-up (HR2.98; 95% CI 1.12-7.88; p < 0.03). In patients with HFrEF, the presence of PVR ≥ 5.0 Wu is associated with significantly worse clinical outcome at follow-up. Non-invasive estimation of PVR by cardiac magnetic resonance might be useful for risk stratification in HFrEF, irrespective of etiology, presence of late gadolinium enhancement or LVEF.

  12. Electrical resistivity and induced polarization tomography in identifying the plume of chlorinated hydrocarbons in sedimentary formation: a case study in Rho (Milan - Italy).

    Science.gov (United States)

    Cardarelli, Ettore; Di Filippo, Gerardina

    2009-09-01

    Resistivity and induced polarization surveying were originally developed for mineral exploration but are now finding new applications in the field of environmental and engineering geophysics. The present article reports the results of a geophysical survey performed with the aim of identifying a plume of chlorinated hydrocarbons in sedimentary formations of the Pandania plain. The tested site is characterized by three sand and gravel aquifers containing a quantity of clay particles which influence the overall bulk resistivity and chargeability. According to data obtained using shallow boreholes, mainly dense non-aqueous phase liquids were found as contaminants in the first and second aquifer. The aforementioned geo-electrical methods were applied in both two- and three-dimensional approaches. Steel and copper electrodes were used in the process of field data acquisition and the results of the survey were compared. The geophysical survey revealed some anomalies that could be explained by the presence of dense non-aqueous phase liquids in the soil medium. The concept of normalized chargeability facilitates the interpretation of detected induced polarization anomalies. The shape of the plume was inferred from maps of resistivity and chargeability to a depth of 25 m below the surface of the ground.

  13. The Isopach Mapping of Volcanic Deposits of Mount Samalas 1257 AD Based on the Values of Resistivity and Physical Properties

    Directory of Open Access Journals (Sweden)

    Hiden Hiden

    2017-08-01

    Full Text Available A detailed study had been conducted on the sediment of Mount Samalas’ volcanic eruption in 1257 AD. Using the framework of the reconstruction of the ancient eruption of Mount Samalas, the first step was to map and analyze the deposits of volcanic sediment. Secondly, we analyzed the effect of geomorphology and the distance function to the isopach thickness. The results show that a combination of methods allowed to provide a high resolution map of the distribution of the thickness of the volcanic deposits, both on the slope and in alluvial areas. Geo-electric survey results (both Vertical Electric Sound (VES and 2D mapping show consistent changes in the pattern of contrast resistivity layer interface, for all areas. The pattern changes in a row of the top layer, the high resistivity turned into the low. Furthermore, the second and third layer interface changes from low to the high resistivity. High resistivity on the top layer is interpreted as a layer of unconsolidated volcanic sediment. High resistivity values are range from 736 to 2000 Ohm.m on the top layer in the area of the slopes while in the area of alluvial, the resistivity values range from 20 to 958 Ohm.m. Generally, the volcanic deposits in the area of the slopes have a higher value of isopach (>17 m than in areas of alluvial (<25 m. The geomorphology seemed to have no significant effect on the isopach value, particularly pyroclastic fallout. Such is the case with distance from the source to the site, which is not linear. The value of isopach increases westward from 21 to 31 km, in contrast to the East, which began to occur at a distance of 14 km to 21 km.

  14. High accuracy of predicting hybrid performance of Fusarium head blight resistance by mid-parent values in wheat.

    Science.gov (United States)

    Miedaner, Thomas; Schulthess, Albert W; Gowda, Manje; Reif, Jochen C; Longin, C Friedrich H

    2017-02-01

    Mid-parent values of Fusarium head blight (FHB) resistance tested across several locations are a good predictor of hybrid performance caused by a preponderance of additive gene action in wheat. Hybrid breeding is intensively discussed as one solution to boost yield and yield stability including an enhanced biotic stress resistance. Our objectives were to investigate (1) the heterosis for Fusarium head blight (FHB) resistance, (2) the importance of general (GCA) vs. specific combining ability (SCA) for FHB resistance, and (3) the possibility to predict the FHB resistance of the hybrids by the parental means. We re-analyzed phenotypic data of a large population comprising 1604 hybrids and their 120 female and 15 male parental lines evaluated in inoculation trials across seven environments. Mid-parent heterosis of FHB severity averaged -9%, with a range from -36 to +35%. Mean better parent heterosis was 2% and 78 of the hybrids significantly (P hybrids (r = 0.09, P hybrid performance of FHB severity based on mid-parent values and on GCA effects was high (r = 0.70 and 0.86, respectively; P hybrids are an attractive alternative variety type to improve FHB resistance.

  15. Using a multi-method approach based on soil radon deficit, resistivity, and induced polarization measurements to monitor non-aqueous phase liquid contamination in two study areas in Italy and India.

    Science.gov (United States)

    Castelluccio, Mauro; Agrahari, Sudha; De Simone, Gabriele; Pompilj, Francesca; Lucchetti, Carlo; Sengupta, Debashish; Galli, Gianfranco; Friello, Pierluigi; Curatolo, Pierpaolo; Giorgi, Riccardo; Tuccimei, Paola

    2018-02-20

    Geochemical and geophysical surveys employing radon deficit, resistivity, and induced polarization (IP) measurements were undertaken on soil contaminated with non-aqueous phase liquids (NAPLs) in two different sites in India and in Italy. Radon deficit, validated through the comparison with average soil radon in reference unpolluted areas, shows the extension of contamination in the upper part of the unsaturated aquifers. In site 1 (Italy), the spill is not recent. A residual film of kerosene covers soil grains, inhibiting their chargeability and reducing electrical resistivity difference with background unpolluted areas. No correlation between the two parameters is observed. Soil volatile organic compounds (VOCs) concentration is not linked with radon deficit, supporting the old age of the spillage. NAPL pollution in sites 2a and 2b (India) is more recent and probably still active, as demonstrated by higher values of electrical resistivity. A good correlation with IP values suggests that NAPL is still distributed as droplets or as a continuous phase in the pores, strengthening the scenario of a fresh spill or leakage. Residual fraction of gasoline in the pore space of sites 2a and 2b is respectively 1.5 and 11.8 kg per cubic meter of terrain. This estimation is referred to the shallower portion of the unsaturated aquifer. Electrical resistivity is still very high indicating that the gasoline has not been strongly degraded yet. Temperature and soil water content influence differently radon deficit in the three areas, reducing soil radon concentration and partly masking the deficit in sites 2a and 2b.

  16. Polarization Optics

    OpenAIRE

    Fressengeas, Nicolas

    2010-01-01

    The physics of polarization optics *Polarized light propagation *Partially polarized light; DEA; After a brief introduction to polarization optics, this lecture reviews the basic formalisms for dealing with it: Jones Calculus for totally polarized light and Stokes parameters associated to Mueller Calculus for partially polarized light.

  17. Using Expectancy Value Theory as a Framework to Reduce Student Resistance to Active Learning: A Proof of Concept.

    Science.gov (United States)

    Cooper, Katelyn M; Ashley, Michael; Brownell, Sara E

    2017-01-01

    There has been a national movement to transition college science courses from passive lectures to active learning environments. Active learning has been shown to be a more effective way for students to learn, yet there is concern that some students are resistant to active learning approaches. Although there is much discussion about student resistance to active learning, few studies have explored this topic. Furthermore, a limited number of studies have applied theoretical frameworks to student engagement in active learning. We propose using a theoretical lens of expectancy value theory to understand student resistance to active learning. In this study, we examined student perceptions of active learning after participating in 40 hours of active learning. We used the principal components of expectancy value theory to probe student experience in active learning: student perceived self-efficacy in active learning, value of active learning, and potential cost of participating in active learning. We found that students showed positive changes in the components of expectancy value theory and reported high levels of engagement in active learning, which provide proof of concept that expectancy value theory can be used to boost student perceptions of active learning and their engagement in active learning classrooms. From these findings, we have built a theoretical framework of expectancy value theory applied to active learning.

  18. Restricted access Improved hydrogeophysical characterization and monitoring through parallel modeling and inversion of time-domain resistivity andinduced-polarization data

    Science.gov (United States)

    Johnson, Timothy C.; Versteeg, Roelof J.; Ward, Andy; Day-Lewis, Frederick D.; Revil, André

    2010-01-01

    Electrical geophysical methods have found wide use in the growing discipline of hydrogeophysics for characterizing the electrical properties of the subsurface and for monitoring subsurface processes in terms of the spatiotemporal changes in subsurface conductivity, chargeability, and source currents they govern. Presently, multichannel and multielectrode data collections systems can collect large data sets in relatively short periods of time. Practitioners, however, often are unable to fully utilize these large data sets and the information they contain because of standard desktop-computer processing limitations. These limitations can be addressed by utilizing the storage and processing capabilities of parallel computing environments. We have developed a parallel distributed-memory forward and inverse modeling algorithm for analyzing resistivity and time-domain induced polar-ization (IP) data. The primary components of the parallel computations include distributed computation of the pole solutions in forward mode, distributed storage and computation of the Jacobian matrix in inverse mode, and parallel execution of the inverse equation solver. We have tested the corresponding parallel code in three efforts: (1) resistivity characterization of the Hanford 300 Area Integrated Field Research Challenge site in Hanford, Washington, U.S.A., (2) resistivity characterization of a volcanic island in the southern Tyrrhenian Sea in Italy, and (3) resistivity and IP monitoring of biostimulation at a Superfund site in Brandywine, Maryland, U.S.A. Inverse analysis of each of these data sets would be limited or impossible in a standard serial computing environment, which underscores the need for parallel high-performance computing to fully utilize the potential of electrical geophysical methods in hydrogeophysical applications.

  19. Multiple antibiotic-resistant bacteria on fluted pumpkin leaves, a herb of therapeutic value.

    Science.gov (United States)

    Igbeneghu, Oluwatoyin A; Abdu, Abdulrasheed B

    2014-06-01

    Fluted pumpkin (Telfairia occidentalis) is a minimally-processed green leafy vegetable traditionally used for its antianaemic properties in the form of leaf juice without a heating or inactivation step before consumption. The aim of the study was to assess the presence of surface microbiota on T. occidentalis leaves and also to determine the antimicrobial susceptibility of isolated organisms. Bacterial contaminants on 50 samples of T. occidentalis leaves were isolated and characterized using standard biochemical methods and the antimicrobial susceptibility of isolated organisms was determined using the antibiotic disc diffusion assay. The results obtained show that the leaves of T. occidentalis is contaminated with organisms which included Enterobacter agglomerans (25.9%), Proteus vulgaris (24.9%), Klebsiella spp. (2.6%), and Serratia liquefaciens (2.1%). Other bacterial isolates recovered in order of frequency included: Staphylococcus spp. (33.7%), Bacillus spp. (8.3%), and Pseudomonas fluorescens (2.6%). Of the 193 bacterial isolates from the leaves of T. occidentalis samples tested for antimicrobial resistance, all (100%) were found to be resistant to ampicillin, cloxacillin, augmentin, erythromycin, and tetracycline while 96% of the isolates were resistant to cephalothin. Resistance to trimethoprim (93%) and gentamicin (83%) was also observed. Approximately, 22% of the isolates were resistant to ciprofloxacin; however, only 11 (5.8%) were resistant to ofloxacin. Thus, uncooked T. occidentalis is a potential source of highly-resistant epiphytic bacteria which could be opportunistic pathogens in consumers.

  20. Myeloid Sirtuin 6 Deficiency Causes Insulin Resistance in High-Fat Diet-Fed Mice by Eliciting Macrophage Polarization Toward an M1 Phenotype.

    Science.gov (United States)

    Lee, Youngyi; Ka, Sun-O; Cha, Hye-Na; Chae, Yu-Na; Kim, Mi-Kyung; Park, So-Young; Bae, Eun Ju; Park, Byung-Hyun

    2017-10-01

    Obesity-related insulin resistance is closely associated with macrophage accumulation and subsequent cytokine release in local tissues. Sirtuin 6 (Sirt6) is known to exert an anti-inflammatory function, but its role in macrophages in the context of obesity has not been investigated. We generated myeloid-specific Sirt6 knockout (mS6KO) mice and investigated the metabolic characteristics after high-fat diet (HFD) feeding for 16 weeks. Compared with their wild-type littermates, HFD-fed mS6KO mice exhibited greater increases in body weight, fasting blood glucose and insulin levels, hepatic steatosis, glucose intolerance, and insulin resistance. Gene expression, histology, and flow cytometric analyses demonstrated that liver and adipose tissue inflammation were elevated in HFD-fed mS6KO mice relative to wild type, with a greater accumulation of F4/80 + CD11b + CD11c + adipose tissue macrophages. Myeloid Sirt6 deletion facilitated proinflammatory M1 polarization of bone marrow macrophages and augmented the migration potential of macrophages toward adipose-derived chemoattractants. Mechanistically, Sirt6 deletion in macrophages promoted the activation of nuclear factor-κB (NF-κB) and endogenous production of interleukin-6, which led to STAT3 activation and the positive feedback circuits for NF-κB stimulation; this cross talk expedited an M1 polarization. We conclude that Sirt6 in macrophages is required for the prevention of obesity-associated tissue inflammation and insulin resistance. © 2017 by the American Diabetes Association.

  1. Polarity-Free Resistive Switching Characteristics of CuxO Films for Non-volatile Memory Applications

    International Nuclear Information System (INIS)

    Hang-Bing, Lv; Peng, Zhou; Xiu-Feng, Fu; Ming, Yin; Ya-Li, Song; Li, Tang; Ting-Ao, Tang; Yin-Yin, Lin

    2008-01-01

    Resistive switching characteristics of Cu x O films grown by plasma oxidation process at room temperature are investigated. Both bipolar and unipolar stable resistive switching behaviours are observed and confirmed by repeated current–voltage measurements. It is found that the RESET current is dependent on SET compliance current. The mechanism behind this new phenomenon can be understood in terms of conductive filaments formation/rupture with the contribution of Joule heating

  2. Value of American Thoracic Society guidelines in predicting infection or colonization with multidrug-resistant organisms in critically ill patients.

    Directory of Open Access Journals (Sweden)

    Jianfeng Xie

    Full Text Available The incidence rate of infection by multidrug-resistant organisms (MDROs can affect the accuracy of etiological diagnosis when using American Thoracic Society (ATS guidelines. We determined the accuracy of the ATS guidelines in predicting infection or colonization by MDROs over 18 months at a single ICU in eastern China.This prospective observational study examined consecutive patients who were admitted to an intensive care unit (ICU in Nanjing, China. MDROs were defined as bacteria that were resistant to at least three antimicrobial classes, such as methicillin-resistant Staphylococcus aureus (MRSA, vancomycin-resistant enterococci (VRE, Pseudomonas aeruginosa, Acinetobacter baumannii. Screening for MDROs was performed at ICU admission and discharge. Risk factors for infection or colonization with MDROs were recorded, and the accuracy of the ATS guidelines in predicting infection or colonization with MDROs was documented.There were 610 patients, 225 (37% of whom were colonized or infected with MDROs at ICU admission, and this increased to 311 (51% at discharge. At admission, the sensitivity (70.0%, specificity (31.6%, positive predictive value (38.2%, and negative predictive value (63.5%, all based on ATS guidelines for infection or colonization with MDROs were low. The negative predictive value was greater in patients from departments with MDRO infection rates of 31-40% than in patients from departments with MDRO infection rates of 30% or less and from departments with MDRO infection rates more than 40%.ATS criteria were not reliable in predicting infection or colonization with MDROs in our ICU. The negative predictive value was greater in patients from departments with intermediate rates of MDRO infection than in patients from departments with low or high rates of MDRO infection.ClinicalTrials.gov NCT01667991.

  3. The predictive value of renal vascular resistance for late renal allograft loss

    NARCIS (Netherlands)

    de Vries, APJ; van Son, WJ; van der Heide, JJH; Ploeg, RJ; Navis, G; de Jong, PE; Gans, ROB; Bakker, SJL; Gansevoort, RT

    The renal artery resistance index (RI), assessed by Doppler ultrasonography, was recently identified as a new risk marker for late renal allograft loss. This finding requires confirmation since RI in that study was not measured at predetermined time points and ultrasonography is operator-dependent.

  4. The predictive value of renal vascular resistance for late renal allograft loss

    NARCIS (Netherlands)

    de Vries, A. P. J.; van Son, W. J.; Homan van der Heide, J. J.; Ploeg, R. J.; Navis, G.; de Jong, P. E.; Gans, R. O. B.; Bakker, S. J. L.; Gansevoort, R. T.

    2006-01-01

    The renal artery resistance index (RI), assessed by Doppler ultrasonography, was recently identified as a new risk marker for late renal allograft loss. This finding requires confirmation since RI in that study was not measured at predetermined time points and ultrasonography is operator-dependent.

  5. Use of cyclic current reversal polarization voltammetry for investigating the relationship between corrosion resistance and heat-treatment induced variations in microstructures of 400 C martensitic stainless steels

    Science.gov (United States)

    Ambrose, John R.

    1992-01-01

    Software for running a cyclic current reversal polarization voltammagram has been developed for use with a EG&G Princeton Applied Research Model 273 potentiostat/galvanostat system. The program, which controls the magnitude, direction and duration of an impressed galvanostatic current, will produce data in ASCII spreadsheets (Lotus, Quattro) for graphical representation of CCRPV voltammograms. The program was used to determine differences in corrosion resistance of 440 C martenstic stainless steel produced as a result of changes in microstructure effected by tempering. It was determined that tempering at all temperatures above 400 F resulted in increased polarizability of the material, with the increased likelihood that pitting would be initiated upon exposure to marine environments. These results will be used in development of remedial procedures for lowering the susceptibility of these alloys toward the stress corrosion cracking experienced in bearings used in high pressure oxygen turbopumps used in the main engines of space shuttle orbiters.

  6. Development of MATLAB Scripts for the Calculation of Thermal Manikin Regional Resistance Values

    Science.gov (United States)

    2016-01-01

    EXECUTIVE SUMMARY A software tool has been developed via MATLAB® scripts to reduce the amount of repetitive and time-consuming calculations that are...the evaporative resistance of clothing using a sweating manikin. West Conshohocken, PA: ASTM International, 2010. 3. ISO 9920. Ergonomics of...producing heat at the rate of 58 W/m2) comfortable in an environment at 21°C, air movement 0.1 m/s, or roughly the insulation of a heavy business suit

  7. Evaluation of reference values for phenotypic tests to detect oxacillin resistance in coagulase-negative staphylococci.

    Science.gov (United States)

    Pinheiro, Luiza; Mello, Priscila L; Abraão, Ligia M; Corrente, José Eduardo; Lourdes Rs Cunha, Maria de

    2018-03-09

    To evaluate the adequacy of the disc-diffusion test and E-test ® compared with detection of mecA for coagulase-negative staphylococci isolated from blood cultures, nasal swabs and wounds. Agreement between all techniques was observed in 65.7% of cases. The greatest discrepancy between mecA/susceptible E-test was observed for non-epidermidis species. A resistance breakpoint ≤19 mm using the oxacillin disc was found to best classify all coagulase-negative staphylococci isolates; Staphylococcus epidermidis, ≤19 mm (oxacillin) and ≤27 mm (cefoxitin); Staphylococcus haemolyticus and Staphylococcus capitis, ≤21 mm (oxacillin) and ≤18 mm (cefoxitin); Staphylococcus warneri, MICs ≥0.75 mg/l. Although no longer recommended by the Clinical Laboratory Standards Institute, we observed some cases in which only the oxacillin disc-diffusion test detected resistance. The discrepancy between phenotypic tests and mecA is probably due to heterogeneity and borderline resistance.

  8. Our Polar Past

    Science.gov (United States)

    Clary, Renee; Wandersee, James

    2009-01-01

    The study of polar exploration is fascinating and offers students insights into the history, culture, and politics that affect the developing sciences at the farthest ends of Earth. Therefore, the authors think there is value in incorporating polar exploration accounts within modern science classrooms, and so they conducted research to test their…

  9. Estimation Of Productive Value Of Czech Origin Scab-Resistant Apple Cultivars On Different Rootstocks

    Directory of Open Access Journals (Sweden)

    Sosna Ireneusz

    2014-12-01

    Full Text Available Apple cultivars resistant to scab are suitable for the conventional and organic cultivation. Rootstocks impact on the growth of trees, yield and fruit quality of scab-resistant cultivars were examined in the experiment conducted at Fruit Experimental Station - Samotwór near Wrocław, during the years 1998-2008. In the spring of 1998, the trees of five Czech origin scab-resistant apple cultivars ‘Rosana’, ‘Rubinola’, ‘Rajka’, ‘Goldstar’ and ‘Topaz’ each on M.9, P2, P60, P16 and P22 rootstocks were planted at a spacing of 3.5 × 1.2 m (2380 trees per hectare. The results of 11-year-long studies showed that ‘Rubinola’ and ‘Rajka’ were characterised by the strongest vigour, while ‘Rosana’ grew much weaker. Significant differences in the cumulative yield were not observed between cultivars, but rootstocks influenced cropping instantly. Trees on rootstock P60 had biggest cross-section area and canopy volume, and the highest cumulative yield. Fruit weight was highest from trees on M9 and P60. ‘Topaz’ and ‘Rosana’ formed significantly lightest fruits and ‘Goldstar’ the heaviest. Trees on the super-dwarfing P22 rootstock grew and yielded very weakly and produced very small fruits. The greatest susceptibility to powdery mildew (Podosphaera leucotricha was observed in ‘Topaz’ and ‘Rajka’. ‘Rubinola’ has the best potential for organic cultivation, especially on dwarfing rootstocks.

  10. Translational value of mechanical and vasomotor properties of mouse isolated mesenteric resistance-sized arteries

    DEFF Research Database (Denmark)

    Outzen, Emilie Middelbo; Zaki, Marina; Abdolalizadeh, Bahareh

    2015-01-01

    Mice are increasingly used in vascular research for studying perturbations and responses to vasoactive agents in small artery preparations. Historically, small artery function has preferably been studied in rat isolated mesenteric resistance-sized arteries (MRA) using the wire myograph technique...... for maximal active force development in mouse MRA were not significantly different to those determined in rat MRA. Furthermore, we found that the observed concentration-dependent vasomotor responses of mouse MRA to noradrenaline, phenylephrine, angiotensin II, sarafotoxin 6c, 5-hydroxytryptamine, carbachol...

  11. Value of a dual-polarized gap-filling radar in support of southern California post-fire debris-flow warnings

    Science.gov (United States)

    Jorgensen, David P.; Hanshaw, Maiana N.; Schmidt, Kevin M.; Laber, Jayme L; Staley, Dennis M.; Kean, Jason W.; Restrepo, Pedro J.

    2011-01-01

    A portable truck-mounted C-band Doppler weather radar was deployed to observe rainfall over the Station Fire burn area near Los Angeles, California, during the winter of 2009/10 to assist with debris-flow warning decisions. The deployments were a component of a joint NOAA–U.S. Geological Survey (USGS) research effort to improve definition of the rainfall conditions that trigger debris flows from steep topography within recent wildfire burn areas. A procedure was implemented to blend various dual-polarized estimators of precipitation (for radar observations taken below the freezing level) using threshold values for differential reflectivity and specific differential phase shift that improves the accuracy of the rainfall estimates over a specific burn area sited with terrestrial tipping-bucket rain gauges. The portable radar outperformed local Weather Surveillance Radar-1988 Doppler (WSR-88D) National Weather Service network radars in detecting rainfall capable of initiating post-fire runoff-generated debris flows. The network radars underestimated hourly precipitation totals by about 50%. Consistent with intensity–duration threshold curves determined from past debris-flow events in burned areas in Southern California, the portable radar-derived rainfall rates exceeded the empirical thresholds over a wider range of storm durations with a higher spatial resolution than local National Weather Service operational radars. Moreover, the truck-mounted C-band radar dual-polarimetric-derived estimates of rainfall intensity provided a better guide to the expected severity of debris-flow events, based on criteria derived from previous events using rain gauge data, than traditional radar-derived rainfall approaches using reflectivity–rainfall relationships for either the portable or operational network WSR-88D radars. Part of the reason for the improvement was due to siting the radar closer to the burn zone than the WSR-88Ds, but use of the dual-polarimetric variables

  12. Establishing streptomycin epidemiological cut-off values for Salmonella and Escherichia coli. Microbial Drug Resistance

    NARCIS (Netherlands)

    Garcia-Migura, L.; Sunde, M.; Karlsmose, S.; Veldman, K.T.; Schroeter, A.; Guerra, B.; Granier, S.A.; Perrin-Guyomard, A.; Gicquel-Bruneau, M.; Franco, A.; Englund, S.; Teale, C.; Heiska, H.; Clemente, L.; Boerlin, P.; Moreno, M.A.; Daignault, D.; Mevius, D.J.; Hendriksen, R.S.; Aarestrup, F.M.

    2012-01-01

    This study was conducted to elucidate the accuracy of the current streptomycin epidemiological cut-off value (ECOFF) for Escherichia coli and Salmonella spp. A total of 236 Salmonella enterica and 208 E. coli isolates exhibiting MICs between 4 and 32¿mg/L were selected from 12 countries. Isolates

  13. Combined DC resistivity and induced polarization (DC-IP) for mapping the internal composition of a mine waste rock pile in Nova Scotia, Canada

    Science.gov (United States)

    Power, Christopher; Tsourlos, Panagiotis; Ramasamy, Murugan; Nivorlis, Aristeidis; Mkandawire, Martin

    2018-03-01

    Mine waste rock piles (WRPs) can contain sulfidic minerals whose interaction with oxygen and water can generate acid mine drainage (AMD). Thus, WRPs can be a long-term source of environmental pollution. Since the generation of AMD and its release into the environment is dependent on the net volume and bulk composition of waste rock, effective characterization of WRPs is necessary for successful remedial design and monitoring. In this study, a combined DC resistivity and induced polarization (DC-IP) approach was employed to characterize an AMD-generating WRP in the Sydney Coalfield, Nova Scotia, Canada. Two-dimensional (2D) DC-IP imaging with 6 survey lines was performed to capture the full WRP landform. 2D DC results indicated a highly heterogeneous and moderately conductive waste rock underlain by a resistive bedrock containing numerous fractures. 2D IP (chargeability) results identified several highly-chargeable regions within the waste, with normalized chargeability delineating regions specific to waste mineralogy only. Three-dimensional (3D) DC-IP imaging, using 17 parallel lines on the plateau of the pile, was then used to focus on the composition of the waste rock. The full 3D inverted DC-IP distributions were used to identify coincident and continuous zones (isosurfaces) of low resistivity (0.4 mS/m) that were inferred as generated AMD (leachate) and stored AMD (sulfides), respectively. Integrated geological, hydrogeological and geochemical data increased confidence in the geoelectrical interpretations. Knowledge on the location of potentially more reactive waste material is extremely valuable for improved long-term AMD monitoring at the WRP.

  14. Culture as a predictor of resistance to change: a study of competing values in a psychiatric nursing context.

    Science.gov (United States)

    Johansson, Catrin; Åström, Sture; Kauffeldt, Anders; Helldin, Lars; Carlström, Eric

    2014-02-01

    It is well known that a conservative organizational culture can hinder the implementation of new organizational models. Prior to introducing something new it is important to identify the culture within the organization. This paper sets out to detect the feasibility of reform in a psychiatric clinic in a Swedish hospital prior to implementation of a new working method - a structured tool based on the International Classification of Functioning Disability and Health. A survey consisting of two instruments - an organizational values questionnaire (OVQ) and a resistance to change scale (RTC) - was distributed to registered and assistant nurses at the clinic. The association between the organizational subcultures and resistance to change was investigated with regression analysis. The results revealed that the dominating cultures in the outpatient centers and hospital wards were characterized by human relation properties such as flexibility, cohesion, belongingness, and trust. The mean resistance to change was low, but the subscale of cognitive rigidity was dominant, reflecting a tendency to avoid alternative ideas and perspectives. An instrument like the one employed in the study could be a useful tool for diagnosing the likelihood of extensive and costly interventions. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Opening the mind to close it: considering a message in light of important values increases message processing and later resistance to change.

    Science.gov (United States)

    Blankenship, Kevin L; Wegener, Duane T

    2008-02-01

    Past research showed that considering a persuasive message in light of important rather than unimportant values creates attitudes that resist later attack. The traditional explanation is that the attitudes come to express the value or that a cognitive link between the value and attitude enhances resistance. However, the current research showed that another explanation is plausible. Similar to other sources of involvement, considering important rather than unimportant values increases processing of the message considered in light of those values. This occurs when the values are identified as normatively high or low in importance and when the perceived importance differs across participants for the same values. The increase in processing creates resistance to later attacks, and unlike past research, individual-level measures of initial amount of processing mediate value importance effects on later resistance to change. Important values motivate processing because they increase personal involvement with the issue, rather than creating attitudes that represent or express core values. (c) 2008 APA, all rights reserved

  16. The cutoff values of indirect indices for measuring insulin resistance for metabolic syndrome in Korean children and adolescents

    Directory of Open Access Journals (Sweden)

    Jun Woo Kim

    2016-09-01

    Full Text Available PurposeThe prevalence rates of metabolic syndrome (MetS and percentile distribution of insulin resistance (IR among Korean children and adolescents were investigated. The cutoff values of IR were calculated to identify high-risk MetS groups.MethodsData from 3,313 Korean subjects (1,756 boys and 1,557 girls, aged 10–18 years were included from the Korean National Health and Nutrition Examination Survey conducted during 2007–2010. Three different sets of criteria for MetS were used. Indirect measures of IR were homeostasis model assessment (HOMA-IR and triglyceride and glucose (TyG index. The cutoff values of the HOMA-IR and TyG index were obtained from the receiver operation characteristic curves.ResultsAccording to the MetS criteria of de Ferranti el al., Cook et al., and the International Diabetes Federation, the prevalence rates in males and females were 13.9% and 12.3%, 4.6% and 3.6%, and 1.4% and 1.8%, respectively. Uses these 3 criteria, the cutoff values of the HOMA-IR and TyG index were 2.94 and 8.41, 3.29 and 8.38, and 3.54 and 8.66, respectively. The cutoff values using each of the 3 criteria approximately corresponds to the 50th–75th, 75th, and 75th–90th percentiles of normal HOMA-IR and TyG index levels.ConclusionThis study describes the prevalence rates of MetS in Korean children and adolescents, an index of IR, and the cutoff values for MetS with the aim of detecting high-risk groups. The usefulness of these criteria needs to be verified by further evaluation.

  17. The Heat Resistance of Microbial Cells Represented by D Values Can be Estimated by the Transition Temperature and the Coefficient of Linear Expansion.

    Science.gov (United States)

    Nakanishi, Koichi; Kogure, Akinori; Deuchi, Keiji; Kuwana, Ritsuko; Takamatsu, Hiromu; Ito, Kiyoshi

    2015-01-01

    We previously developed a method for evaluating the heat resistance of microorganisms by measuring the transition temperature at which the coefficient of linear expansion of a cell changes. Here, we performed heat resistance measurements using a scanning probe microscope with a nano thermal analysis system. The microorganisms studied included six strains of the genus Bacillus or related genera, one strain each of the thermophilic obligate anaerobic bacterial genera Thermoanaerobacter and Moorella, two strains of heat-resistant mold, two strains of non-sporulating bacteria, and one strain of yeast. Both vegetative cells and spores were evaluated. The transition temperature at which the coefficient of linear expansion due to heating changed from a positive value to a negative value correlated strongly with the heat resistance of the microorganism as estimated from the D value. The microorganisms with greater heat resistance exhibited higher transition temperatures. There was also a strong negative correlation between the coefficient of linear expansion and heat resistance in bacteria and yeast, such that microorganisms with greater heat resistance showed lower coefficients of linear expansion. These findings suggest that our method could be useful for evaluating the heat resistance of microorganisms.

  18. The value of effective public tuberculosis treatment: an analysis of opportunity costs associated with multidrug resistant tuberculosis in Latvia

    Science.gov (United States)

    2013-01-01

    Background A challenge to effective protection against tuberculosis is to sustain expensive and complex treatment public programs. Potential consequences of program failure include acquired drug resistance, poor patient outcomes, and potentially much higher system costs, however. In contrast, effective efforts have value illustrated by impacts they prevent. We compared the healthcare costs and treatment outcomes among multidrug-resistant tuberculosis (MDR-TB) and non MDR-TB patients in Latvia to identify benefits or costs associated with both. Methods We measured and compared costs, healthcare utilization, and outcomes for patients who began treatment through Latvia’s TB control program in 2002 using multivariate regression analysis and negative binomial regression. Results We analyzed data for 92 MDR-TB and 54 non MDR-TB patients. Most (67%) MDR-TB patients had history of prior tuberculosis treatment. MDR-TB was associated with lower cure rates (71% vs. 91%) and greater resource utilization. MDR-TB treatment cost almost $20,000 more than non MDR-TB. Conclusion Up to 2/3 of MDR-TB treated in our sample was preventable at a potential savings of over $1.3 million in healthcare resources as well as substantial individual health. PMID:23594422

  19. INFLUENCE OF SINTERING TEMPERATURE ON THE POLARIZATION RESISTANCE OF LaO20.6SrO20.4CoO20.2FeO20.8O3-δ - SDC CARBONATE COMPOSITE CATHODE

    Directory of Open Access Journals (Sweden)

    Nurul Akidah Baharuddin

    2016-05-01

    Full Text Available The effects of sintering temperature of an LSCF-samarium-doped ceria carbonate (SDCC cathode composite film on its polarization resistance (Rp were evaluated in this study. An LSCF-SDCC composite cathode was prepared for cathode film development by electrophoretic deposition (EPD. The LSCF-SDCC composite cathode was prepared at 50:50 weight percentage ratio. An EPD suspension which is based on an organic aqueous solution was used, and a mixture of ethanol and deionized water was used as medium with poly diallyl dimethyl ammonium chloride (PDADMAC as a dispersing agent. SDCC substrate was used, and EPD was performed on both sides. A symmetrical cell with cathode composite LSCF-SDCC films on both sides of the substrate was subjected to sintering at five different temperatures (from 550°C to 750°C. A symmetrical cell was painted using silver paste before undergoing electrochemical performance test (air condition, in which the impedance, Z data, was measured. The effects of sintering temperature change on element content and film porosity were first investigated by energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy, and J-image analysis. Ceramic-based cathode LSCF-SDCC that was sintered at 600°C exhibited the lowest Rp at a value of 0.68 Ω when operated at 650°C. This study proved that EPD has potential in developing IT-LT solid oxide fuel cell cathode components with high electrochemical performance in terms of Rp values.

  20. Polarization developments

    International Nuclear Information System (INIS)

    Prescott, C.Y.

    1993-07-01

    Recent developments in laser-driven photoemission sources of polarized electrons have made prospects for highly polarized electron beams in a future linear collider very promising. This talk discusses the experiences with the SLC polarized electron source, the recent progress with research into gallium arsenide and strained gallium arsenide as a photocathode material, and the suitability of these cathode materials for a future linear collider based on the parameters of the several linear collider designs that exist

  1. Limited predictive value of the IDF definition of metabolic syndrome for the diagnosis of insulin resistance measured with the oral minimal model.

    Science.gov (United States)

    Ghanassia, E; Raynaud de Mauverger, E; Brun, J-F; Fedou, C; Mercier, J

    2009-01-01

    To assess the agreement of the NCEP ATP-III and the IDF definitions of metabolic syndrome and to determine their predictive values for the diagnosis of insulin resistance. For this purpose, we recruited 150 subjects (94 women and 56 men) and determined the presence of metabolic syndrome using the NCEP-ATP III and IDF definitions. We evaluated their insulin sensitivity S(I) using Caumo's oral minimal model after a standardized hyperglucidic breakfast test. Subjects whose S(I) was in the lowest quartile were considered as insulin resistant. We then calculated sensitivity, specificity, positive and negative predictive values of both definitions for the diagnosis of insulin resistance. The prevalence of metabolic syndrome was 37.4% (NCEP-ATP III) and 40% (IDF). Agreement between the two definitions was 96%. Using NCEP-ATP III and IDF criteria for the identification of insulin resistant subjects, sensitivity was 55.3% and 63%, specificity was 68.8% and 67.8%, positive predictive value was 37.5% and 40%, negative predictive value was 81.9% and 84.5%, respectively. Positive predictive value increased with the number of criteria for both definitions. Whatever the definition, the scoring of metabolic syndrome is not a reliable tool for the individual diagnosis of insulin resistance, and is more useful for excluding this diagnosis.

  2. RHIC Polarized proton operation

    International Nuclear Information System (INIS)

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D'Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.E.; Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-01-01

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP 4 . A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  3. RHIC Polarized proton operation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D' Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R,; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; J.; Severino, F.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J. Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-03-28

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP{sup 4}. A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  4. Fractal analysis of polar bear hairs

    Directory of Open Access Journals (Sweden)

    Wang Qing-Li

    2015-01-01

    Full Text Available Hairs of a polar bear (Ursus maritimus are of superior properties such as the excellent thermal protection. Why do polar bears can resist such cold environment? The paper concludes that its fractal porosity plays an important role, and its fractal dimensions are very close to the golden mean, 1.618, revealing the possible optimal structure of polar bear hair.

  5. Polarization, political

    NARCIS (Netherlands)

    Wojcieszak, M.; Mazzoleni, G.; Barnhurst, K.G.; Ikeda, K.; Maia, R.C.M.; Wessler, H.

    2015-01-01

    Polarization has been studied in three different forms: on a social, group, and individual level. This entry first focuses on the undisputed phenomenon of elite polarization (i.e., increasing adherence of policy positions among the elites) and also outlines different approaches to assessing mass

  6. Polarization holography

    DEFF Research Database (Denmark)

    Nikolova, L.; Ramanujam, P.S.

    Current research into holography is concerned with applications in optically storing, retrieving, and processing information. Polarization holography has many unique properties compared to conventional holography. It gives results in high efficiency, achromaticity, and special polarization...... properties. This books reviews the research carried out in this field over the last 15 years. The authors provide basic concepts in polarization and the propagation of light through anisotropic materials, before presenting a sound theoretical basis for polarization holography. The fabrication...... and characterization of azobenzene based materials, which remain the most efficient for the purpose, is described in detail. This is followed by a description of other materials that are used in polarization holography. An in-depth description of various applications, including display holography and optical storage...

  7. Spectral Doppler Waveforms for Diagnosis of Appendicitis: Potential Utility of Point Peak Systolic Velocity and Resistive Index Values.

    Science.gov (United States)

    Shin, Lewis K; Jeffrey, R Brooke; Berry, Gerald J; Olcott, Eric W

    2017-12-01

    Purpose To test the hypothesis that appendiceal spectral Doppler waveforms can distinguish patients with and patients without appendicitis. Materials and Methods In this retrospective study, Doppler waveforms were obtained from intramural appendiceal arteries identified with color Doppler imaging in 60% (93 of 155) of consecutive patients whose appendices were visualized at graded compression ultrasonography (US) performed for suspected appendicitis (53 male and 40 female; age, 1-56 years; mean, 14.5 years) over the 5-month period from November 2015 through March 2016. Point, non-angle-corrected peak systolic velocity (PSV) and resistive index (RI) values were compared between patients with and patients without appendicitis by utilizing histopathologically proven appendicitis and 6-week clinical follow-up as diagnostic reference standards. Data were assessed by using the Student t test, exact binomial distribution, two-sample test of proportions, and receiver operating characteristic analysis. Results Among the 93 patients, 36 (38.7%) had proven appendicitis (mean PSV, 19.7 cm/sec; mean RI, 0.69) and 57 patients (61.2%) did not (mean PSV, 7.1 cm/sec, P appendicitis was 0.97 (95% confidence interval [CI]: 0.95, 1.00) for PSV and 0.86 (95% CI: 0.78, 0.95; P = .011) for RI. Chosen discriminatory criteria of PSV greater than 10 cm/sec and RI greater than 0.65 yielded specificity for appendicitis of 94.7% and 96.5% with sensitivity of 88.9% and 63.9% (P = .013) and negative predictive value of 93.1% and 80.9% (P = .045), respectively. Original clinical graded compression US interpretations based on established US findings demonstrated specificity of 96.2% and sensitivity of 100.0%. Considering the subset of 20 patients whose maximum outer diameter measured 6-8 mm, the discriminatory criteria of PSV greater than 10 cm/sec and RI greater than 0.65 yielded specificity for appendicitis of 88.9% each, with sensitivity of 100.0% and 63.6% and negative predictive value of 100

  8. Optimal Waist Circumference Cutoff Value Based on Insulin Resistance and Visceral Obesity in Koreans with Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Jung Soo Lim

    2015-06-01

    Full Text Available BackgroundVisceral obesity is the most powerful contributor to the development of metabolic syndrome (MetS and cardiovascular diseases. In light of visceral obesity, however, there is a paucity of data on the appropriate cutoff point of waist circumference (WC in subjects with type 2 diabetes. The aim of this study was to investigate the optimal cutoff value for WC that signals insulin resistance (IR and visceral obesity in Koreans with type 2 diabetes.MethodsWe evaluated 4,252 patients with type 2 diabetes (male 2,220, female 2,032, mean age 57.24 years who visited our clinic between January 2003 and June 2009. WC was measured at the midpoint between the lower rib and the iliac crest, and insulin sensitivity was assessed by the rate constant of plasma glucose disappearance (Kitt %/min using an insulin tolerance test. Visceral fat thickness was measured using ultrasonography. Statistical analysis was performed using receiver operating characteristic curve.ResultsThe optimal cutoff points for WC for identifying the presence of IR and visceral obesity, as well as two or more metabolic components, were 87 cm for men and 81 cm for women. Moreover, these cutoff points had the highest predictive powers for the presence of visceral obesity. The MetS defined by new criteria correlated with the increased carotid intima-media thickness in female subjects.ConclusionOur results suggest that the optimal cutoff values for WC in Koreans with type 2 diabetes should be reestablished based on IR and visceral obesity.

  9. The European iNPH Multicentre Study on the predictive values of resistance to CSF outflow and the CSF Tap Test in patients with idiopathic normal pressure hydrocephalus

    DEFF Research Database (Denmark)

    Wikkelsø, Carsten; Hellström, Per; Klinge, Petra Margarete

    2013-01-01

    The objective was to determine the sensitivity, specificity, and positive and negative predictive values of the CSF Tap Test (CSF TT) and resistance to CSF outflow (Rout) for the outcome of shunting in a sample of patients with idiopathic normal pressure hydrocephalus (iNPH).......The objective was to determine the sensitivity, specificity, and positive and negative predictive values of the CSF Tap Test (CSF TT) and resistance to CSF outflow (Rout) for the outcome of shunting in a sample of patients with idiopathic normal pressure hydrocephalus (iNPH)....

  10. Polar Bears

    Science.gov (United States)

    Amstrup, Steven C.; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

    2002-01-01

    Polar bears (Ursus maritimus) are hunted throughout most of their range. In addition to hunting polar bears of the Beaufort Sea region are exposed to mineral and petroleum extraction and related human activities such as shipping road-building, and seismic testing (Stirling 1990).Little was known at the start of this project about how polar bears move about in their environment, and although it was understood that many bears travel across political borders, the boundaries of populations had not been delineated (Amstrup 1986, Amstrup et al. 1986, Amstrup and DeMaster 1988, Garner et al. 1994, Amstrup 1995, Amstrup et al. 1995, Amstrup 2000).As human populations increase and demands for polar bears and other arctic resources escalate, managers must know the sizes and distributions of the polar bear populations. Resource managers also need reliable estimates of breeding rates, reproductive intervals, litter sizes, and survival of young and adults.Our objectives for this research were 1) to determine the seasonal and annual movements of polar bears in the Beaufort Sea, 2) to define the boundaries of the population(s) using this region, 3) to determine the size and status of the Beaufort Sea polar bear population, and 4) to establish reproduction and survival rates (Amstrup 2000).

  11. Clinical value of NPHS2 analysis in early- and adult-onset steroid-resistant nephrotic syndrome.

    Science.gov (United States)

    Santín, Sheila; Tazón-Vega, Bárbara; Silva, Irene; Cobo, María Ángeles; Giménez, Isabel; Ruíz, Patricia; García-Maset, Rafael; Ballarín, José; Torra, Roser; Ars, Elisabet

    2011-02-01

    To date, very few cases with adult-onset focal segmental glomerulosclerosis (FSGS) carrying NPHS2 variants have been described, all of them being compound heterozygous for the p.R229Q variant and one pathogenic mutation. Mutation analysis was performed in 148 unrelated Spanish patients, of whom 50 presented with FSGS after 18 years of age. Pathogenicity of amino acid substitutions was evaluated through an in silico scoring system. Haplotype analysis was carried out using NPHS2 single nucleotide polymorphism and microsatellite markers. Compound heterozygous or homozygous NPHS2 pathogenic mutations were identified in seven childhood-onset steroid-resistant nephrotic syndrome (SRNS) cases. Six additional cases with late childhood- and adult-onset SRNS were compound heterozygotes for p.R229Q and one pathogenic mutation, mostly p.A284V. p.R229Q was more frequent among SRNS cases relative to controls (odds ratio=2.65; P=0.02). Significantly higher age at onset of the disease and slower progression to ESRD were found in patients with one pathogenic mutation plus the p.R229Q variant in respect to patients with two NPHS2 pathogenic mutations. NPHS2 analysis has a clinical value in both childhood- and adult-onset SRNS patients. For adult-onset patients, the first step should be screening for p.R229Q and, if positive, for p.A284V. These alleles are present in conserved haplotypes, suggesting a common origin for these substitutions. Patients carrying this specific NPHS2 allele combination did not respond to corticoids or immunosuppressors and showed FSGS, average 8-year progression to ESRD, and low risk for recurrence of FSGS after kidney transplant.

  12. Effects of resistive bodies on DC electrical soundings

    Directory of Open Access Journals (Sweden)

    L. Alfano

    1996-06-01

    Full Text Available Some deep DC electrical soundings, performed in alpine and apenninic areas with the continuous polar dipole-dipole spread, show apparent resistivity curves with positive slopes. Measured values of apparent resistivity reach 30000 Wm. Applying the "surface charges" method we developed three dimensional mathematical models, by means of which we can state simple rules for determining the minimum extensions of the deep resistive bodies, fundamental information for a more precise interpretation of the field results.

  13. Defining landscape resistance values in least-cost connectivity models for the invasive grey squirrel: a comparison of approaches using expert-opinion and habitat suitability modelling.

    Directory of Open Access Journals (Sweden)

    Claire D Stevenson-Holt

    Full Text Available Least-cost models are widely used to study the functional connectivity of habitat within a varied landscape matrix. A critical step in the process is identifying resistance values for each land cover based upon the facilitating or impeding impact on species movement. Ideally resistance values would be parameterised with empirical data, but due to a shortage of such information, expert-opinion is often used. However, the use of expert-opinion is seen as subjective, human-centric and unreliable. This study derived resistance values from grey squirrel habitat suitability models (HSM in order to compare the utility and validity of this approach with more traditional, expert-led methods. Models were built and tested with MaxEnt, using squirrel presence records and a categorical land cover map for Cumbria, UK. Predictions on the likelihood of squirrel occurrence within each land cover type were inverted, providing resistance values which were used to parameterise a least-cost model. The resulting habitat networks were measured and compared to those derived from a least-cost model built with previously collated information from experts. The expert-derived and HSM-inferred least-cost networks differ in precision. The HSM-informed networks were smaller and more fragmented because of the higher resistance values attributed to most habitats. These results are discussed in relation to the applicability of both approaches for conservation and management objectives, providing guidance to researchers and practitioners attempting to apply and interpret a least-cost approach to mapping ecological networks.

  14. Defining landscape resistance values in least-cost connectivity models for the invasive grey squirrel: a comparison of approaches using expert-opinion and habitat suitability modelling.

    Science.gov (United States)

    Stevenson-Holt, Claire D; Watts, Kevin; Bellamy, Chloe C; Nevin, Owen T; Ramsey, Andrew D

    2014-01-01

    Least-cost models are widely used to study the functional connectivity of habitat within a varied landscape matrix. A critical step in the process is identifying resistance values for each land cover based upon the facilitating or impeding impact on species movement. Ideally resistance values would be parameterised with empirical data, but due to a shortage of such information, expert-opinion is often used. However, the use of expert-opinion is seen as subjective, human-centric and unreliable. This study derived resistance values from grey squirrel habitat suitability models (HSM) in order to compare the utility and validity of this approach with more traditional, expert-led methods. Models were built and tested with MaxEnt, using squirrel presence records and a categorical land cover map for Cumbria, UK. Predictions on the likelihood of squirrel occurrence within each land cover type were inverted, providing resistance values which were used to parameterise a least-cost model. The resulting habitat networks were measured and compared to those derived from a least-cost model built with previously collated information from experts. The expert-derived and HSM-inferred least-cost networks differ in precision. The HSM-informed networks were smaller and more fragmented because of the higher resistance values attributed to most habitats. These results are discussed in relation to the applicability of both approaches for conservation and management objectives, providing guidance to researchers and practitioners attempting to apply and interpret a least-cost approach to mapping ecological networks.

  15. System for measuring the proton polarization in a polarized target

    International Nuclear Information System (INIS)

    Karnaukhov, I.M.; Lukhanin, A.A.; Telegin, Yu.N.; Trotsenko, V.I.; Chechetenko, V.F.

    1984-01-01

    The system for measuring the proton polarization in a polarized target representing the high-sensitivity nuclear magnetic resonance (NMR) is described Q-meter with series connection and a circuit for measuring system resonance characteristic is used for NMR-absorption signal recording. Measuring coil is produced of a strip conductor in order to obtain uniform system sensitivity to polarization state in all target volume and improve signal-to-noise ratio. Polarization measuring system operates ion-line with the M-6000 computer. The total measuring error for the value of free proton polarization in target taking into account the error caused by local depolarization of working substance under irradiation by high-intense photon beam is <= 6%. Long-term application of the described system for measuring the proton polarization in the LUEh-20000 accelerator target used in the pion photoproduction experiments has demonstrated its high reliability

  16. A polarized alkali ion source

    International Nuclear Information System (INIS)

    Boettger, R.; Tungate, G.; Bauer, B.; Egelhof, P.; Moebius, K.H.; Steffens, E.

    1978-01-01

    The beam foil technique has been applied to detect nuclear vector polarization of a 10 keV 23 Na + beam. The result was about 70% of the atomic beam polarization thus limiting the depolarization by the surface ionizer to at most 30%. In a Coulomb excitation experiment with a tensor polarized 42 MeV 23 Na 7+ beam an effect of 0.011 +- 0.003 was measured yielding a value of t 20 approx. 0.04 for the beam polarization. The depolarization during the acceleration process can be estimated to be about 0.8. (orig.) [de

  17. Evaluation of epidemiological cut-off values indicates that biocide resistant subpopulations are uncommon in natural isolates of clinically-relevant microorganisms.

    Directory of Open Access Journals (Sweden)

    Ian Morrissey

    Full Text Available To date there are no clear criteria to determine whether a microbe is susceptible to biocides or not. As a starting point for distinguishing between wild-type and resistant organisms, we set out to determine the minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC distributions for four common biocides; triclosan, benzalkonium chloride, chlorhexidine and sodium hypochlorite for 3319 clinical isolates, with a particular focus on Staphylococcus aureus (N = 1635 and Salmonella spp. (N = 901 but also including Escherichia coli (N = 368, Candida albicans (N = 200, Klebsiella pneumoniae (N = 60, Enterobacter spp. (N = 54, Enterococcus faecium (N = 53, and Enterococcus faecalis (N = 56. From these data epidemiological cut-off values (ECOFFs are proposed. As would be expected, MBCs were higher than MICs for all biocides. In most cases both values followed a normal distribution. Bimodal distributions, indicating the existence of biocide resistant subpopulations were observed for Enterobacter chlorhexidine susceptibility (both MICs and MBCs and the susceptibility to triclosan of Enterobacter (MBC, E. coli (MBC and MIC and S. aureus (MBC and MIC. There is a concern on the potential selection of antibiotic resistance by biocides. Our results indicate however that resistance to biocides and, hence any potential association with antibiotic resistance, is uncommon in natural populations of clinically relevant microorganisms.

  18. Multi-Valued Planar Hall Resistance Manipulated by Current Induced Magnetic Field in Fe Films Grown on GaAs(001) Substrates

    Science.gov (United States)

    Khym, Sungwon; Yoo, Taehee; Lee, Hakjoon; Lee, Sangyeop; Lee, Sanghoon; Liu, Xinyu; Furdyna, Jacek K.; Lee, Dong Uk; Kim, Eun Kyu

    2012-09-01

    A Hall device was fabricated from single-crystal Fe film having two in-plane magnetic easy axes. Planar Hall resistance measured by sequential application of current pulses to the metal strip that was deposited on the top of a Hall bar showed a hysteresis similar to that observed by scanning an external magnetic field. It was shown that discrete Hall resistance values in the hysteresis, which correspond to specific multidomain structures in Fe film, can be created by the application of appropriate sequences of current pulses to the metal strip, and can thus be used for read/write logic applications.

  19. Political polarization

    OpenAIRE

    Dixit, Avinash K.; Weibull, Jörgen W.

    2007-01-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality.

  20. Political polarization.

    Science.gov (United States)

    Dixit, Avinash K; Weibull, Jörgen W

    2007-05-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality.

  1. Modeling charge polarization voltage for large lithium-ion batteries in electric vehicles

    Directory of Open Access Journals (Sweden)

    Yan Jiang

    2013-06-01

    Full Text Available Purpose: Polarization voltage of the lithium-ion battery is an important parameter that has direct influence on battery performance. The paper aims to analyze the impedance characteristics of the lithium-ion battery based on EIS data. Design/methodology/approach: The effects of currents, initial SOC of the battery on charge polarization voltage are investigated, which is approximately linear function of charge current. The change of charge polarization voltage is also analyzed with the gradient analytical method in the SOC domain. The charge polarization model with two RC networks is presented, and parts of model parameters like Ohmic resistance and charge transfer impedance are estimated by both EIS method and battery constant current testing method. Findings: This paper reveals that the Ohmic resistance accounts for much contribution to battery total polarization compared to charge transfer impedance. Practical implications: Experimental results demonstrate the efficacy of the model with the proposed identification method, which provides the foundation for battery charging optimization. Originality/value: The paper analyzed the impedance characteristics of the lithium-ion battery based on EIS data, presented a charge polarization model with two RC networks, and estimated parameters like Ohmic resistance and charge transfer impedance.

  2. The reinforcing value and liking of resistance training and aerobic exercise as predictors of adult’s physical actively behavior

    Science.gov (United States)

    Background: Reinforcing value is a stronger predictor than hedonic value (liking) for engaging in drug use, gambling, and eating. The associations of reinforcing value and liking with physical activity of adults have not yet been studied and may depend on the mode of exercise available during exerc...

  3. Kramers-Kronig relations for interstellar polarization

    International Nuclear Information System (INIS)

    Martin, P.G.

    1975-01-01

    The difficulties encountered in using the Kramers-Kronig relations to predict the behavior of interstellar polarization are pointed out, while at the same time their value in an interpretive role is acknowledged. Observations of interstellar circular polarization lead to restrictions on the interstellar grain composition, and additional constraints should be possible through measurement of linear polarization in the infrared and the ultraviolet

  4. Individual blood pressure responses to walking and resistance exercise in peripheral artery disease patients: Are the mean values describing what is happening?

    Science.gov (United States)

    Lima, Aluísio H R A; Miranda, Alessandra S; Correia, Marilia A; Soares, Antônio H G; Cucato, Gabriel G; Sobral Filho, Dario C; Gomes, Silvana L; Ritti-Dias, Raphael M

    2015-12-01

    The aim of this study was to analyze the average and individual blood pressure responses to walking and resistance exercise in patients with peripheral artery disease. Thirteen patients underwent three experimental sessions: walking exercise, resistance exercise, and control. Ambulatory blood pressure, heart rate, and rate pressure product were obtained before and until 24 hours after sessions. The mean cardiovascular values during 24 hours, awake, and sleep periods were similar (P > 0.05) after the three experimental sessions. The analysis of individual data revealed that during 24 hours, eight of 13 patients reduced systolic or diastolic blood pressure in ≥4.0 mm Hg in at least one of the exercise session; furthermore, most of these patients presented greater responses after resistance exercise. The clinical characteristics of patients seem to influence the blood pressure responses after exercises. Individual data showed that part of patients presented clinically significant decreases in blood pressure, showing that these patients have acute cardiovascular benefits after performing an acute bout of exercise. Although, in average, a bout of walking or resistance exercise did not decrease ambulatory blood pressure in peripheral artery disease patients, the individual data revealed that most patients presented clinically relevant blood pressure reductions, especially after resistance exercise. Copyright © 2015 Society for Vascular Nursing, Inc. Published by Elsevier Inc. All rights reserved.

  5. Insulin resistance (HOMA-IR) cut-off values and the metabolic syndrome in a general adult population: effect of gender and age: EPIRCE cross-sectional study.

    Science.gov (United States)

    Gayoso-Diz, Pilar; Otero-González, Alfonso; Rodriguez-Alvarez, María Xosé; Gude, Francisco; García, Fernando; De Francisco, Angel; Quintela, Arturo González

    2013-10-16

    Insulin resistance has been associated with metabolic and hemodynamic alterations and higher cardio metabolic risk. There is great variability in the threshold homeostasis model assessment of insulin resistance (HOMA-IR) levels to define insulin resistance. The purpose of this study was to describe the influence of age and gender in the estimation of HOMA-IR optimal cut-off values to identify subjects with higher cardio metabolic risk in a general adult population. It included 2459 adults (range 20-92 years, 58.4% women) in a random Spanish population sample. As an accurate indicator of cardio metabolic risk, Metabolic Syndrome (MetS), both by International Diabetes Federation criteria and by Adult Treatment Panel III criteria, were used. The effect of age was analyzed in individuals with and without diabetes mellitus separately. ROC regression methodology was used to evaluate the effect of age on HOMA-IR performance in classifying cardio metabolic risk. In Spanish population the threshold value of HOMA-IR drops from 3.46 using 90th percentile criteria to 2.05 taking into account of MetS components. In non-diabetic women, but no in men, we found a significant non-linear effect of age on the accuracy of HOMA-IR. In non-diabetic men, the cut-off values were 1.85. All values are between 70th-75th percentiles of HOMA-IR levels in adult Spanish population. The consideration of the cardio metabolic risk to establish the cut-off points of HOMA-IR, to define insulin resistance instead of using a percentile of the population distribution, would increase its clinical utility in identifying those patients in whom the presence of multiple metabolic risk factors imparts an increased metabolic and cardiovascular risk. The threshold levels must be modified by age in non-diabetic women.

  6. The value of nasal mupirocin in containing an outbreak of methicillin- resistant Staphylococcus aureus in an orthopaedic unit

    NARCIS (Netherlands)

    S.P. Barrett

    1990-01-01

    textabstractAn outbreak of methicillin-resistant Staphylococcus aureus (MRSA) occurred in two adjacent orthopaedic wards following the admission of a known carrier. The outbreak was not contained by ward closure or by standard infection control measures. Eventually several nasal carriers were

  7. FORCED OSCILLATION TECHNIQUE - REFERENCE VALUES FOR TOTAL RESPIRATORY RESISTANCE OBTAINED WITH THE SIEMENS SIREGNOST-FD5

    NARCIS (Netherlands)

    GIMENO, F; VANDERWEELE, LT; KOETER, GH; VANALTENA, R

    Total respiratory resistance (Rrs) was measured by the application of a sine wave of airflow to the mouth at an oscillation frequency of 10 Hz. The instrument used was the Siemens Siregnost FD5. The Rrs data were correlated with height, age, sex, and weight in 73 patients and 29 healthy subjects.

  8. Final report on RMO comparison SIM.EM-S10: High value resistance comparison with two-terminal cryogenic current comparators

    Science.gov (United States)

    Bierzychudek, Marcos E.; Elmquist, Randolph; Hernández, Felipe

    2014-01-01

    This work presents a supplementary comparison of high value resistance standards performed during 2012 and January 2013, following the guidelines presented in a document about measurement comparisons in the CIPM MRA. The purpose of this task was to compare the high resistance cryogenic current comparator scaling of the participating institutes: National Institute of Standards and Technology, USA (NIST), Centro Nacional de Metrología, Mexico (CENAM) and Instituto Nacional de Tecnología Industrial, Argentina (INTI), all of which are members of the Sistema Interamericano de Metrología (SIM) Regional Metrology Organization. All the measurements of this comparison were performed with two-terminal cryogenic current comparators (CCC). Degrees of equivalence of the participating institutes relative to the comparison reference values are given in the report for the measured resistance values. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by SIM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  9. Sacred values in the Israeli-Palestinian conflict: resistance to social influence, temporal discounting, and exit strategies.

    Science.gov (United States)

    Sheikh, Hammad; Ginges, Jeremy; Atran, Scott

    2013-09-01

    Conflicts over sacred values may be particularly difficult to resolve. Because sacred values are nonfungible with material values, standard attempts to negotiate, such as offering material incentives to compromise, often backfire, increasing moral outrage and support for violent action. We present studies with Palestinians in the West Bank and Gaza demonstrating three other ways sacred values may make conflict more intractable, focusing on what we call devoted actors, people who regard issues central to the Israel-Palestine conflict as sacred values. We show that devoted actors (1) were less amenable to social influence, (2) perceived conflict-related events in the past as well as expected events in the future to be temporally closer, and (3) were blind to individual opportunities to escape the conflict. These results suggest that sacred values may affect decision making in a number of ways, which, when combined, contribute to common defense and continuation of conflict. © 2013 New York Academy of Sciences.

  10. The value of microscopic-observation drug susceptibility assay in the diagnosis of tuberculosis and detection of multidrug resistance.

    Science.gov (United States)

    Sertel Şelale, Denİz; Uzun, Meltem

    2018-01-01

    Inexpensive, rapid, and reliable tests for detecting the presence and drug susceptibility of Mycobacterium tuberculosis complex (MTBC) are urgently needed to control the transmission of tuberculosis. In this study, we aimed to assess the accuracy and speed of the microscopic-observation drug susceptibility (MODS) assay in the identification of MTBC and detection of multidrug resistance. Sputum samples from patients suspected to have tuberculosis were simultaneously tested with MODS and conventional culture [Löwenstein-Jensen (LJ) culture, BACTEC MGIT™ 960 (MGIT) system], and drug susceptibility testing (MGIT system) methods. A total of 331 sputum samples were analyzed. Sensitivity and specificity of MODS assay for detection of MTBC strains were 96% and 98.8%, respectively. MODS assay detected multidrug resistant MTBC isolates with 92.3% sensitivity and 96.6% specificity. Median time to culture positivity was similar for MGIT (8 days) and MODS culture (8 days), but was significantly longer with LJ culture (20 days) (p tuberculosis and detection of multidrug resistance. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  11. Anodic Concentration Polarization in SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Williford, Rick E.; Chick, Lawrence A.; Maupin, Gary D.; Simner, Steve P.; Stevenson, Jeffry W.; Khaleel, Mohammad A.; Wachsman, ED, et al

    2003-08-01

    Concentration polarization is important because it determines the maximum power output of a solid oxide fuel cell (SOFC) at high fuel utilization. Anodic concentration polarization occurs when the demand for reactants exceeds the capacity of the porous ceramic anode to supply them by gas diffusion mechanisms. High tortuosities (bulk diffusion resistances) are often assumed to explain this behavior. However, recent experiments show that anodic concentration polarization originates in the immediate vicinity of the reactive triple phase boundary (TPB) sites near the anode/electrolyte interface. A model is proposed to describe how concentration polarization is controlled by two localized phenomena: competitive adsorption of reactants in areas adjacent to the reactive TPB sites, followed by relatively slow surface diffusion to the reactive sites. Results suggest that future SOFC design improvements should focus on optimization of the reactive area, adsorption, and surface diffusion at the anode/electrolyte interface.

  12. Spontaneous growth of polarizing refractory metal ‘nano-fins’

    Science.gov (United States)

    Tai, M. C.; Gentle, A. R.; Arnold, M. D.; Cortie, M. B.

    2018-03-01

    Traditional polymer polarizers degrade in harsh environments and at high temperatures, reducing the polarization effect. In contrast, polarizers produced with refractory metals have vastly improved thermal stability and resistance to harsh environments but are expensive to fabricate. Here we demonstrate prototype refractory metal wire grid polarizers produced by co-sputtering molybdenum and aluminum under specific conditions. Removal of the aluminum through selective dissolution enables the nanostructure array to transmit light. The polarization spans 500–1100 nm and the extinction ratio significantly increases to >100. Possessing broadband polarization and sufficient extinction ratios, the new polarizing film has potential applications in coatings for sunglasses, windows, pyrometers, scientific instruments, and LCD panels.

  13. Strategic Polarization.

    Science.gov (United States)

    Kalai, Adam; Kalai, Ehud

    2001-08-01

    In joint decision making, similarly minded people may take opposite positions. Consider the example of a marriage in which one spouse gives generously to charity while the other donates nothing. Such "polarization" may misrepresent what is, in actuality, a small discrepancy in preferences. It may be that the donating spouse would like to see 10% of their combined income go to charity each year, while the apparently frugal spouse would like to see 8% donated. A simple game-theoretic analysis suggests that the spouses will end up donating 10% and 0%, respectively. By generalizing this argument to a larger class of games, we provide strategic justification for polarization in many situations such as debates, shared living accommodations, and disciplining children. In some of these examples, an arbitrarily small disagreement in preferences leads to an arbitrarily large loss in utility for all participants. Such small disagreements may also destabilize what, from game-theoretic point of view, is a very stable equilibrium. Copyright 2001 Academic Press.

  14. Optimal cut-off value for homeostasis model assessment (HOMA) index of insulin-resistance in a population of patients admitted electively in a Portuguese cardiology ward.

    Science.gov (United States)

    Timóteo, Ana Teresa; Miranda, Fernando; Carmo, Miguel Mota; Ferreira, Rui Cruz

    2014-01-01

    Insulin resistance is the pathophysiological key to explain metabolic syndrome. Although clearly useful, the Homeostasis Model Assessment index (an insulin resistance measurement) has not been systematically applied in clinical practice. One of the main reasons is the discrepancy in cut-off values reported in different populations. We sought to evaluate in a Portuguese population the ideal cut-off for Homeostasis Model Assessment index and assess its relationship with metabolic syndrome. We selected a cohort of individuals admitted electively in a Cardiology ward with a BMI validation cohort of 300 individuals (no exclusion criteria applied). From 7 000 individuals, and after the exclusion criteria, there were left 1 784 individuals. The 90th percentile for Homeostasis Model Assessment index was 2.33. In the validation cohort, applying that cut-off, we have 49.3% of individuals with insulin resistance. However, only 69.9% of the metabolic syndrome patients had insulin resistance according to that cut-off. By ROC curve analysis, the ideal cut-off for metabolic syndrome is 2.41. Homeostasis Model Assessment index correlated with BMI (r = 0.371, p < 0.001) and is an independent predictor of the presence of metabolic syndrome (OR 19.4, 95% CI 6.6 - 57.2, p < 0.001). Our study showed that in a Portuguese population of patients admitted electively in a Cardiology ward, 2.33 is the Homeostasis Model Assessment index cut-off for insulin resistance and 2.41 for metabolic syndrome. Homeostasis Model Assessment index is directly correlated with BMI and is an independent predictor of metabolic syndrome.

  15. HAWC+/SOFIA Instrumental Polarization Calibration

    Science.gov (United States)

    Michail, Joseph M.; Chuss, David; Dowell, Charles D.; Santos, Fabio; Siah, Javad; Vaillancourt, John; HAWC+ Instrument Team

    2018-01-01

    HAWC+ is a new far-infrared polarimeter for the NASA/DLR SOFIA (Stratospheric Observatory for Infrared Astronomy) telescope. HAWC+ has the capability to measure the polarization of astronomical sources with unprecedented sensitivity and angular resolution in four bands from 50-250 microns. Using data obtained during commissioning flights, we implemented a calibration strategy that separates the astronomical polarization signal from the induced instrumental polarization. The result of this analysis is a map of the instrumental polarization as a function of position in the instrument's focal plane in each band. The results show consistency between bands, as well as with other methods used to determine preliminary instrumental polarization values.

  16. Geomagnetic polarity transitions

    Science.gov (United States)

    Merrill, Ronald T.; McFadden, Phillip L.

    1999-05-01

    reasonable to draw the following conclusions with varying degrees of confidence. There appears to be a substantial decrease in the mean intensity of the dipole field during a transition to ˜25% of its usual value. The duration of an average geomagnetic polarity transition is not well known but probably lies between 1000 and 8000 years. Values outside these bounds have been reported, but we give reasons as to why such outliers are likely to be artifacts. The reversal process is probably longer than the manifestation of the reversal at Earth's surface as recorded in paleomagnetic directional data. Convection hiatus during a geomagnetic polarity transition seems unlikely, and free-decay models for reversals appear to be generally incompatible with the data. This implies that certain theorems in dynamo theory, such as Cowling's theorem, should not be invoked to explain the origin of reversals. Unfortunately, the detailed description of directional changes during transitions remains controversial. Contrary to common belief, certain low-degree nondipole fields can produce significant longitudinal confinement of virtual geomagnetic poles (VGP) during a transition. The data are currently inadequate to refute or verify claims of longitudinal dipole confinement, VGP clustering, or other systematics during polarity transitions.

  17. The use of genomic information increases the accuracy of breeding value predictions for sea louse (Caligus rogercresseyi) resistance in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Correa, Katharina; Bangera, Rama; Figueroa, René; Lhorente, Jean P; Yáñez, José M

    2017-01-31

    Sea lice infestations caused by Caligus rogercresseyi are a main concern to the salmon farming industry due to associated economic losses. Resistance to this parasite was shown to have low to moderate genetic variation and its genetic architecture was suggested to be polygenic. The aim of this study was to compare accuracies of breeding value predictions obtained with pedigree-based best linear unbiased prediction (P-BLUP) methodology against different genomic prediction approaches: genomic BLUP (G-BLUP), Bayesian Lasso, and Bayes C. To achieve this, 2404 individuals from 118 families were measured for C. rogercresseyi count after a challenge and genotyped using 37 K single nucleotide polymorphisms. Accuracies were assessed using fivefold cross-validation and SNP densities of 0.5, 1, 5, 10, 25 and 37 K. Accuracy of genomic predictions increased with increasing SNP density and was higher than pedigree-based BLUP predictions by up to 22%. Both Bayesian and G-BLUP methods can predict breeding values with higher accuracies than pedigree-based BLUP, however, G-BLUP may be the preferred method because of reduced computation time and ease of implementation. A relatively low marker density (i.e. 10 K) is sufficient for maximal increase in accuracy when using G-BLUP or Bayesian methods for genomic prediction of C. rogercresseyi resistance in Atlantic salmon.

  18. Precessing deuteron polarization

    International Nuclear Information System (INIS)

    Sitnik, I.M.; Volkov, V.I.; Kirillov, D.A.; Piskunov, N.M.; Plis, Yu.A.

    2002-01-01

    The feasibility of the acceleration in the Nuclotron of deuterons polarized in the horizontal plane is considered. This horizontal polarization is named precessing polarization. The effects of the main magnetic field and synchrotron oscillations are included. The precessing polarization is supposed to be used in studying the polarization parameters of the elastic dp back-scattering and other experiments

  19. The Prognostic Value of Plasma YKL-40 in Patients With Chemotherapy-Resistant Ovarian Cancer Treated With Bevacizumab

    DEFF Research Database (Denmark)

    Boisen, Mogens K; Madsen, Christine V; Dehlendorff, Christian

    2016-01-01

    with ovarian cancer treated with bevacizumab. METHODS: One hundred forty patients with chemotherapy-refractory epithelian ovarian cancer were treated with single-agent bevacizumab 10 mg/kg every 3 weeks in a prospective trial. Plasma YKL-40 was determined by enzyme-linked immunosorbent assay before and during...... = 0.003). Increase in plasma YKL-40 during bevacizumab treatment, with correction for baseline plasma YKL-40, was a predictor of shorter PFS. Using normal versus elevated plasma YKL-40 as a cutoff did not provide the same discriminative value. CONCLUSIONS: Low plasma YKL-40 at baseline and during...... treatment is associated with improved outcomes in patients with chemotherapy-refractory advanced ovarian cancer treated with single-agent bevacizumab....

  20. Racial/ethnic differences in the influence of cultural values, alcohol resistance self-efficacy, and alcohol expectancies on risk for alcohol initiation.

    Science.gov (United States)

    Shih, Regina A; Miles, Jeremy N V; Tucker, Joan S; Zhou, Annie J; D'Amico, Elizabeth J

    2012-09-01

    Prior research has reported racial/ethnic differences in the early initiation of alcohol use, suggesting that cultural values that are central to specific racial/ethnic groups may be influencing these differences. This 1-year longitudinal study examines associations between two types of cultural values, parental respect (honor for one's parents) and familism (connectedness with family), both measured at baseline, and subsequent alcohol initiation in a sample of 6,054 (approximately 49% male, 57% Hispanic, 22% Asian, 18% non-Hispanic White, and 4% non-Hispanic Black) middle school students in Southern California. We tested whether the associations of cultural values with alcohol initiation could be explained by baseline measures of alcohol resistance self-efficacy (RSE) and alcohol expectancies. We also explored whether these pathways differed by race/ethnicity. In the full sample, adolescents with higher parental respect were less likely to initiate alcohol use, an association that was partially explained by higher RSE and fewer positive alcohol expectancies. Familism was not significantly related to alcohol initiation. Comparing racial/ethnic groups, higher parental respect was protective against alcohol initiation for Whites and Asians, but not Blacks or Hispanics. There were no racial/ethnic differences in the association between familism and alcohol initiation. Results suggest that cultural values are important factors in the decision to use alcohol and these values appear to operate in part, by influencing alcohol positive expectancies and RSE. Interventions that focus on maintaining strong cultural values and building strong bonds between adolescents and their families may help reduce the risk of alcohol initiation. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  1. Polare maskuliniteter

    Directory of Open Access Journals (Sweden)

    Marit Anne Hauan

    2012-05-01

    Full Text Available In this paper my aim is to read and understand the journal of Gerrit de Veer from the last journey of William Barents to the Arctic Regions in 1596 and the journal of captain Junge on his hunting trip from Tromsø to Svalbard in 1834.It is nearly 240 years between this to voyages. The first journal is known as the earliest report from the arctic era. Gerrit de Veer adds instructive copper engravings to his text and give us insight in the crews meeting with this new land. Captain Junges journal is found together with his dead crew in a house in a fjord nearby Ny-Ålesund and has no drawings, but word. Both of these journals may be read as sources of the knowledge and understanding of the polar region. They might also unveil the ideas of how to deal with and survive under the challenges that is given. In addition one can ask if the sources can tell us more about how men describe their challenges. Can the way they expressed themselves in the journals give us an understanding of masculinity? And not least help us to create good questions of the change in the ideas of masculinities which is said to follow the change in understanding of the wilderness.

  2. Deletion of IL-33R (ST2 abrogates resistance to EAE in BALB/C mice by enhancing polarization of APC to inflammatory phenotype.

    Directory of Open Access Journals (Sweden)

    Marija Milovanovic

    Full Text Available The administration of interleukin 33 and deletion of IL-33 receptor, ST2 molecule, affects the induction of autoimmunity in different experimental models of human autoimmune diseases. The aim of this study was to analyze the effect of ST2 deletion on the induction of experimental autoimmune encephalomyelitis (EAE in resistant BALB/c mice. Mice were immunized with MOG(35-55 peptide or disease was induced by passive transfer of encephalitogenic singenic cells and EAE was clinically and histologically evaluated. Expression of intracellular inflammatory cytokines, markers of activation and chemokine receptors on lymphoid tissue and CNS infiltrating mononuclear cells was analyzed by flow cytometry. We report here that deletion of ST2(-/- molecule abrogates resistance of BALB/c mice to EAE induction based on clinical and histopathological findings. Brain and spinal cord infiltrates of ST2(-/- mice had significantly higher number of CD4(+ T lymphocytes containing inflammatory cytokines compared to BALB/c WT mice. Adoptive transfer of ST2(-/- primed lymphocytes induced clinical signs of the disease in ST2(-/- as well as in WT mice. MOG(35-55 restimulated ST2(-/- CD4(+ cells as well as ex vivo analyzed lymph node cells had higher expression of T-bet and IL-17, IFN-γ, TNF-α and GM-CSF in comparison with WT CD4(+ cells. ST2(-/- mice had higher percentages of CD4(+ cells expressing chemokine receptors important for migration to CNS in comparison with WT CD4(+ cells. Draining lymph nodes of ST2(-/- mice contained higher percentage of CD11c(+CD11b(+CD8(- cells containing inflammatory cytokines IL-6 and IL-12 with higher expression of activation markers. Transfer of ST2(-/- but not WT dendritic cells induced EAE in MOG(35-55 immunized WT mice. Our results indicate that ST2 deficiency attenuates inherent resistance of BALB/c mice to EAE induction by enhancing differentiation of proinflammatory antigen presenting cells and consecutive differentiation of

  3. A study of insulin resistance by HOMA-IR and its cut-off value to identify metabolic syndrome in urban Indian adolescents.

    Science.gov (United States)

    Singh, Yashpal; Garg, M K; Tandon, Nikhil; Marwaha, Raman Kumar

    2013-01-01

    Insulin resistance (IR) and associated metabolic abnormalities are increasingly being reported in the adolescent population. Cut-off value of homeostasis model of assessment IR (HOMA-IR) as an indicator of metabolic syndrome (MS) in adolescents has not been established. This study aimed to investigate IR by HOMA-IR in urban Indian adolescents and to establish cut-off values of HOMA-IR for defining MS. A total of 691 apparently healthy adolescents (295 with normal body mass index (BMI), 205 overweight, and 199 obese) were included in this cross-sectional study. MS in adolescents was defined by International Diabetes Federation (IDF) and Adult Treatment Panel III (ATP III) criteria. IR was calculated using the HOMA model. Mean height, waist circumference (WC), waist/hip ratio (WHR), waist/height ratio (WHtR), and blood pressure were significantly higher in boys as compared to girls. The HOMA-IR values increased progressively from normal weight to obese adolescents in both sexes. Mean HOMA-IR values increased progressively according to sexual maturity rating in both sexes. HOMA-IR value of 2.5 had a sensitivity of >70% and specificity of >60% for MS. This cut-off identified larger number of adolescents with MS in different BMI categories (19.7% in normal weight, 51.7% in overweight, and 77.0% in obese subjects) as compared to the use of IDF or ATP III criteria for diagnosing MS. Odds ratio for having IR (HOMA-IR of >2.5) was highest with WHtR (4.9, p pHOMA-IR increased with sexual maturity and with progression from normal to obese. A HOMA-IR cut-off of 2.5 provided the maximum sensitivity and specificity in diagnosing MS in both genders as per ATP III and IDF criteria.

  4. The value of the renal resistive index in the measurement of renal perfusion before and after extracorporal shock wave lithotripsy in correlation to the scintigraphy, to the magnetic resonance perfusion imaging and to big-endothelin values

    International Nuclear Information System (INIS)

    Palwein-Prettner, L.

    1999-07-01

    Purpose: the goal of this study was to evaluate effects of extracorporeal shock wave lithotripsy (ESWL) on the renal perfusion using the resistive index (RI), perfusion scintigraphy, magnetic resonance (MR) perfusion imaging and plasma big-endothelin (big-ET-1) values. Method/materials: In 21 patients divided in 3 age-groups the RI was measured before and 1,3,6 and 24 hours after ESWL. Big-ET-1, a potent vasoconstrictor peptid was correlated with the RI values. The RI and Big-ET-1 results was compared to the results of the MR perfusion imaging and the scintigraphy, the gold-standard method. Results: The RI of the treated kidneys increased significantly from 0,64±0,05 to 0,72±0,08 after the ESWL (p<0,001) and in the untreated kidneys from 0,63±0,05 to 0,68±0,09 (p=0,003). The hightest age group shows the most significant increase. The Big-ET-values also increased only in this age group significantly from 0,78±0,24 fmol/l to 1,58±0,52 fmol/l. In the scintigraphy the decrease of the renal plasma flow (RPF) in this age group was most significant. The MR perfusion Imaging shows in all age groups significant decrease (p<0,001). Conclusion: we conclude that the ESWL causes considerable renal parenchymal damage only in the elderly patients. The following changes in renal perfusion were measured very sensitively with the RI which had a good correlation to the results of the perfusion scintigraphy and the MR perfusion imaging. Further studies with larger series have to evaluate these results. (author)

  5. Ratio of low molecular weight serum adiponectin to the total adiponectin value is associated with type 2 diabetes through its relation to increasing insulin resistance.

    Science.gov (United States)

    Iwata, Minoru; Hara, Kazuo; Kamura, Yutaka; Honoki, Hisae; Fujisaka, Shiho; Ishiki, Manabu; Usui, Isao; Yagi, Kunimasa; Fukushima, Yasuo; Takano, Atsuko; Kato, Hiromi; Murakami, Shihou; Higuchi, Kiyohiro; Kobashi, Chikaaki; Fukuda, Kazuhito; Koshimizu, Yukiko; Tobe, Kazuyuki

    2018-01-01

    Among the three adiponectin isoforms, a lower ratio of high molecular weight (HMW) adiponectin to total adiponectin (TA) is well known to cause insulin resistance and type 2 diabetes (T2D). However, how the levels of other adiponectin isoforms, such as the middle molecular weight (MMW) and low molecular weight (LMW) isoforms, and their relative ratio to TA change in T2D subjects has not been determined. Therefore, we investigated the association of these adiponectin-related parameters with T2D. We examined the associations between adiponectin-related parameters and diabetes in a group of 394 T2D subjects and 374 controls (1st group) randomly selected from among the participants in our previous study. The associations between these parameters and the HOMA-IR in a 2nd group, consisting of the subjects remaining in the 1st group after the exclusion of subjects receiving diabetic medication, were also examined. In the 1st group, after adjusting for confounding factor, the levels of all the adiponectin isoforms and the HMW/TA ratio were significantly lower among the diabetic subjects than among the controls (all P values resistance.

  6. RHIC FY15 pp Run RHIC and AGS polarization analysis

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Adams, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-02-20

    The polarization information is important for the spin physics program in Relativistic Heavy Ion Collider (RHIC). There are discrepancies between AGS and RHIC polarization measurements. First, the face value of AGS polarization is higher than RHIC ones in general. Second, the measured polarization profile (described by the profile ratio R) is stronger in AGS than in RHIC. This note analyzes the polarization data from FY15 pp run period. The results show that the differences between AGS and RHIC polarization measurements are reasonable, but the R value difference is puzzling. The difference between blue and yellow ring is worth of spin simulation to explain.

  7. Polarized electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Prepost, R. [Univ. of Wisconsin, Madison, WI (United States)

    1994-12-01

    The fundamentals of polarized electron sources are described with particular application to the Stanford Linear Accelerator Center. The SLAC polarized electron source is based on the principle of polarized photoemission from Gallium Arsenide. Recent developments using epitaxially grown, strained Gallium Arsenide cathodes have made it possible to obtain electron polarization significantly in excess of the conventional 50% polarization limit. The basic principles for Gallium and Arsenide polarized photoemitters are reviewed, and the extension of the basic technique to strained cathode structures is described. Results from laboratory measurements of strained photocathodes as well as operational results from the SLAC polarized source are presented.

  8. Dynamic nuclear polarization of irradiated target materials

    International Nuclear Information System (INIS)

    Seely, M.L.

    1982-01-01

    Polarized nucleon targets used in high energy physics experiments usually employ the method of dynamic nuclear polarization (DNP) to polarize the protons or deuterons in an alcohol. DNP requires the presence of paramagnetic centers, which are customarily provided by a chemical dopant. These chemically doped targets have a relatively low polarizable nucleon content and suffer from loss of polarization when subjected to high doses of ionizing radiation. If the paramagnetic centers formed when the target is irradiated can be used in the DNP process, it becomes possible to produce targets using materials which have a relatively high polarizable nucleon content, but which are not easily doped by chemical means. Furthermore, the polarization of such targets may be much more radiation resistant. Dynamic nuclear polarization in ammonia, deuterated ammonia, ammonium hydroxide, methylamine, borane ammonia, butonal, ethane and lithium borohydride has been studied. These studies were conducted at the Stanford Linear Accelerator Center using the Yale-SLAC polarized target system. Results indicate that the use of ammonia and deuterated ammonia as polarized target materials would make significant increases in polarized target performance possible

  9. Apparent resistivity of detector grade cadmium telluride

    International Nuclear Information System (INIS)

    Siffert, P.; Rabin, B.; Tabatabai, H.Y.; Stuck, R.

    1977-01-01

    The resistivity of both chlorine compensated and undoped cadmium telluride, grown by the THM or programmed solution growth techniques, have been measured by several methods. Values up to 10 9 Ω.cm have been reached for these P-type samples, in agreement with the literature. However, when used in the detector manufacturing, the total depletion layer thickness at a certain voltage was much less as expected, indicating much lower real resistivities. The origin of this effect is probably due to fast polarization. A procedure is proposed to evaluate quickly the real extension of the depletion layer thickness

  10. System for measuring of proton polarization in polarized target

    International Nuclear Information System (INIS)

    Derkach, A.Ya.; Lukhanin, A.A.; Karnaukhov, I.M.; Kuz'menko, V.S.; Telegin, Yu.N.; Trotsenko, V.I.; Chechetenko, V.F.

    1981-01-01

    Measurement system of proton polarization in the target, which uses the method of nuclear magnetic resonance is described. To record the signal of NMR-absorption a parallel Q-meter of voltage with analogous subtraction of resonance characteristics of measurement circuit is used. To obtain gradual sensitivity of the system to polarization state in the whole volume of the target the measurement coils is made of tape conductor. The analysis and mathematical modelling of Q-meter are carried out. Corrections for nonlinearity and dispersion are calculated. Key diagrams of the main electron blocks of Q-meter are presented. The system described operates on line with the M6000 computer. Total error of measurement of polarization value of free protons in the target does not exceed 6% [ru

  11. Egalitarian norms, economic development, and ethnic polarization

    NARCIS (Netherlands)

    Haagsma, R.; Mouche, van P.H.M.

    2013-01-01

    Economic development generally implies that traditional egalitarian norms and beliefs are replaced by modern individualistic values. Particularly when opportunities for advancement are unequally presented to people, this transformation may be accompanied by polarization and violent conflict. We

  12. Polar drive on OMEGA

    Directory of Open Access Journals (Sweden)

    Radha P.B.

    2013-11-01

    Full Text Available High-convergence polar-drive experiments are being conducted on OMEGA [T. R. Boehly et al., Opt. Commum. 133, 495 (1997] using triple-picket laser pulses. The goal of OMEGA experiments is to validate modeling of oblique laser deposition, heat conduction in the presence of nonradial thermal gradients in the corona, and implosion energetics in the presence of laser–plasma interactions such as crossed-beam energy transfer. Simulated shock velocities near the equator, where the beams are obliquely incident, are within 5% of experimentally inferred values in warm plastic shells, well within the required accuracy for ignition. High, near-one-dimensional areal density is obtained in warm-plastic-shell implosions. Simulated backlit images of the compressing core are in good agreement with measured images. Outstanding questions that will be addressed in the future relate to the role of cross-beam transfer in polar drive irradiation and increasing the energy coupled into the target by decreasing beam obliquity.

  13. Geographical Income Polarization

    DEFF Research Database (Denmark)

    Azhar, Hussain; Jonassen, Anders Bruun

    inter municipal income inequality. Counter factual simulations show that rising property prices to a large part explain the rise in polarization. One side-effect of polarization is tendencies towards a parallel polarization of residence location patterns, where low skilled individuals tend to live......In this paper we estimate the degree, composition and development of geographical income polarization based on data at the individual and municipal level in Denmark from 1984 to 2002. Rising income polarization is reconfirmed when applying new polarization measures, the driving force being greater...

  14. Large enhancement of deuteron polarization with frequency modulated microwaves

    CERN Document Server

    Adeva, B; Arik, S; Arvidson, A; Badelek, B; Ballintijn, M K; Bardin,; Baum, G; Berglund, P; Betev, L; Birda, I G; Birsa, R; Bjrkholm, P; Bonner, B E; de Botton, N; Boutemeur, M; Bradamante, Franco; Bressan, A; Brullc, A; Buchanan, J; Bültmann, S; Burtin, E; Cavata, C; Chen, J P; Clement, J; Clocchiatti, M; Corcoran, M D; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Deshpande, S; Dalla Torre, A; Van Dantzig, R; Dhawan, S; Dulya, C; Dyring, A; Eichblatt, S; Faivre, Jean-Claude; Fasching, D; Day, D; Feinstein, F; Fernández, C; Frois, B; Garabatos, C; Garzón, J A; Gaussiran, T; Giorgi, M; von Goeler, E; Goloutvin, Igor A; Gómez, A; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Gülmez, E; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, D; von Harrach, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; De Jong, M; Kabu, E M; Kageya, T; Kaiser, R; Karev, A; Kessler, H J; Ketel, T J; Kiryushin, Yu T; Kishi, A; Kisselev, Yu; Klostermann, L; Krämer, Dietrich; Kukhtin, V; Kyynarinen, J; Lamanna, M; Landgraf, U; Lau, V; Krivokhijinea, K; Layda, T; Le Go, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Lindqvist, T; Litmaath, M; López-Ponte, S; Loewe, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B; McCarthy, J S; van Middelkoop, K; Medved, G; Miller, D; Mitchell, J; Mori, K; Moromisato, J; Mutchler, G S; Nagaitsev, A; Nassalski, J; Naumann, Lutz; Neganov, B; Niinikoski, T O; Oberski, J E J; Ogawa, A; Okumi, S; Ozben, C S; Penzo, Aldo L; Pérez, C A; Perrot-Kunne, F; Piegaia, R; Pinsky, L; Platchkov, S; Pló, M; Pose, D; Postma, D; Peshekhonov, H; Pretz, J; Pussieux, T; Pyrlik, J; Reyhancan, I; Rieubland, Jean Michel; Rijllart, A; Roberts, J B; Rock, S E; Rodríguez, M; Rondio, E; Rondon, O; Ropelewski, Leszek; Rosado, A; Sabo, I; Saborido, J; Salvato, G; Sandacz, A; Sanders, D; Savin, I; Schiavon, Paolo; Schüler, K P; Segel, R; Seitz, R; Semertzidis, Y; Sergeev, S; Sever, F; Shanahan, P; Sichtermann, E P; Smirnov, G; Staude, A; Steinmetz, A; Stuhrmann, H; Teichert, K M; Tessarotto, F; Thiel, W; Velasco, M; Vogt, J; Voss, R; Weinstein, R; Whitten, C; Willumeit, R; Windmolders, R; Wislicki, W; Witzmann, A; Yañez, A; Zanetti, A M; Zhao, J; Zamiatin, N I

    1996-01-01

    We report a large enhancement of 1.7 in deuteron polarization up to values of 0.6 due to frequency modulation of the polarizing microwaves in a two liters polarized target using the method of dynamic nuclear polarization. This target was used during a deep inelastic polarized muon-deuteron scattering experiment at CERN. Measurements of the electron paramagnetic resonance absorption spectra show that frequency modulation gives rise to additional microwave absorption in the spectral wings. Although these results are not understood theoretically, they may provide a useful testing ground for the deeper understanding of dynamic nuclear polarization.

  15. Polarized Light Corridor Demonstrations.

    Science.gov (United States)

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  16. Study of corrosion resistance of chromium-nickel steel in calcium - hypochlorite solution. Part 1. Steels uranus b6

    Directory of Open Access Journals (Sweden)

    Tošković D.

    2002-01-01

    Full Text Available Corrosion resistance of Cr - Ni (special steels specimen is tested by electrochemical methods, numerical method of linear polarization and polarization resistance method in calcium-hypochlorite (Ca(OCl2 solutions. With increasing of Ca(OCl2 concentration, pH value of the solution increases, as well as active chlorine concentration and corrosion activity of the medium. According to the quantitative method of the corrosion resistance determination it can be concluded that the steels tested in 1 wt % Ca(OCl2 solution are resistant, in 10 wt % solution constant, and in 50 wt % suspension less resistant. URANUS B6 showed the best corrosion resistance of all tested chromium - nickel steels in all tested corrosion mediums.

  17. Polarized Moessbauer transitions

    International Nuclear Information System (INIS)

    Barb, D.

    1975-01-01

    Theoretical aspects of the emission, absorption and scattering of polarized gamma rays are reviewed for a general case of combined magnetic and electric hyperfine interactions; various possibilities of obtaining polarized gamma sources are described and examples are given of the applications of Moessbauer spectroscopy with polarized gamma rays in solving problems of solid state physics. (A.K.)

  18. Polarization Properties of Laser Solitons

    Directory of Open Access Journals (Sweden)

    Pedro Rodriguez

    2017-04-01

    Full Text Available The objective of this paper is to summarize the results obtained for the state of polarization in the emission of a vertical-cavity surface-emitting laser with frequency-selective feedback added. We start our research with the single soliton; this situation presents two perpendicular main orientations, connected by a hysteresis loop. In addition, we also find the formation of a ring-shaped intensity distribution, the vortex state, that shows two homogeneous states of polarization with very close values to those found in the soliton. For both cases above, the study shows the spatially resolved value of the orientation angle. It is important to also remark the appearance of a non-negligible amount of circular light that gives vectorial character to all the different emissions investigated.

  19. The Physics of Polarization

    Science.gov (United States)

    Landi Degl'Innocenti, Egidio

    2015-10-01

    The introductory lecture that has been delivered at this Symposium is a condensed version of an extended course held by the author at the XII Canary Island Winter School from November 13 to November 21, 2000. The full series of lectures can be found in Landi Degl'Innocenti (2002). The original reference is organized in 20 Sections that are here itemized: 1. Introduction, 2. Description of polarized radiation, 3. Polarization and optical devices: Jones calculus and Muller matrices, 4. The Fresnel equations, 5. Dichroism and anomalous dispersion, 6. Polarization in everyday life, 7. Polarization due to radiating charges, 8. The linear antenna, 9. Thomson scattering, 10. Rayleigh scattering, 11. A digression on Mie scattering, 12. Bremsstrahlung radiation, 13. Cyclotron radiation, 14. Synchrotron radiation, 15. Polarization in spectral lines, 16. Density matrix and atomic polarization, 17. Radiative transfer and statistical equilibrium equations, 18. The amplification condition in polarized radiative transfer, and 19. Coupling radiative transfer and statistical equilibrium equations.

  20. Predictive value of prior colonization and antibiotic use for third-generation cephalosporin-resistant enterobacteriaceae bacteremia in patients with sepsis.

    Science.gov (United States)

    Rottier, Wouter C; Bamberg, Yara R P; Dorigo-Zetsma, J Wendelien; van der Linden, Paul D; Ammerlaan, Heidi S M; Bonten, Marc J M

    2015-06-01

    To prevent inappropriate empiric antibiotic treatment in patients with bacteremia caused by third-generation cephalosporin (3GC)-resistant Enterobacteriaceae (3GC-R EB), Dutch guidelines recommend β-lactam and aminoglycoside combination therapy or carbapenem monotherapy in patients with prior 3GC-R EB colonization and/or recent cephalosporin or fluoroquinolone usage. Positive predictive values (PPVs) of these determinants are unknown. We retrospectively studied patients with a clinical infection in whom blood cultures were obtained and empiric therapy with broad-spectrum β-lactams and/or aminoglycosides and/or fluoroquinolones was started. We determined the PPVs of prior colonization and antibiotic use for 3GC-R EB bacteremia, and the consequences of guideline adherence on appropriateness of empiric treatment. Of 9422 episodes, 773 (8.2%) were EB bacteremias and 64 (0.7%) were caused by 3GC-R EB. For bacteremia caused by 3GC-R EB, PPVs of prior colonization with 3GC-R EB (90-day window) and prior usage of cephalosporins or fluoroquinolones (30-day window) were 7.4% and 1.3%, respectively, and PPV was 1.8% for the presence of any of these predictors. Adherence to Dutch sepsis guideline recommendations was 27%. Of bacteremia episodes caused by 3GC-R and 3GC-sensitive EB, 56% and 94%, respectively, were initially treated with appropriate antibiotics. Full adherence to guideline recommendations would hardly augment proportions of appropriate therapy, but could considerably increase carbapenem use. In patients receiving empiric treatment for sepsis, prior colonization with 3GC-R EB and prior antibiotic use have low PPV for infections caused by 3GC-R EB. Strict guideline adherence would unnecessarily stimulate broad-spectrum antibiotic use. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. Emission polarization study on quartz and calcite.

    Science.gov (United States)

    Vincent, R. K.

    1972-01-01

    Calculation of the spectral emission polarization of quartz and calcite polished plates for observation angles of 20 and 70 deg by the substitution of complex index of refraction values for each mineral into Fresnel's equations. The emission polarization is shown to be quite wavelength-dependent, demonstrating that selected narrow or medium-width spectral bands exhibit a significantly higher percentage of polarization than a broad spectral band for these two minerals. Field measurements with a broadband infrared radiometer yield polarizations on the order of 2% for a coarse-grained granite rock and beach sand (both quartz-rich). This implies that a more sensitive detector with a selected medium-width filter may be capable of measuring emission polarization accurately enough to make this parameter useful as a remote sensing tool for discrimination among rocks on the basis of texture.

  2. In vitro activity of ertapenem versus ceftriaxone against Neisseria gonorrhoeae isolates with highly diverse ceftriaxone MIC values and effects of ceftriaxone resistance determinants: ertapenem for treatment of gonorrhea?

    Science.gov (United States)

    Unemo, Magnus; Golparian, Daniel; Limnios, Athena; Whiley, David; Ohnishi, Makoto; Lahra, Monica M; Tapsall, John W

    2012-07-01

    Clinical resistance to the currently recommended extended-spectrum cephalosporins (ESCs), the last remaining treatment options for gonorrhea, is being reported. Gonorrhea may become untreatable, and new treatment options are crucial. We investigated the in vitro activity of ertapenem, relative to ceftriaxone, against N. gonorrhoeae isolates and the effects of ESC resistance determinants on ertapenem. MICs were determined using agar dilution technique or Etest for international reference strains (n = 17) and clinical N. gonorrhoeae isolates (n = 257), which included the two extensively drug-resistant (XDR) strains H041 and F89 and additional isolates with high ESC MICs, clinical ESC resistance, and other types of clinical high-level and multidrug resistance (MDR). Genetic resistance determinants for ESCs (penA, mtrR, and penB) were sequenced. In general, the MICs of ertapenem (MIC(50) = 0.032 μg/ml; MIC(90) = 0.064 μg/ml) paralleled those of ceftriaxone (MIC(50) = 0.032 μg/ml; MIC(90) = 0.125 μg/ml). The ESC resistance determinants mainly increased the ertapenem MIC and ceftriaxone MIC at similar levels. However, the MIC ranges for ertapenem (0.002 to 0.125 μg/ml) and ceftriaxone (gonorrhea, particularly for the currently identified ESC-resistant cases and possibly in a dual antimicrobial therapy regimen. However, further knowledge regarding the genetic determinants (and their evolution) conferring resistance to both antimicrobials, and clear correlates between genetic and phenotypic laboratory parameters and clinical treatment outcomes, is essential.

  3. In Vitro Activity of Ertapenem versus Ceftriaxone against Neisseria gonorrhoeae Isolates with Highly Diverse Ceftriaxone MIC Values and Effects of Ceftriaxone Resistance Determinants: Ertapenem for Treatment of Gonorrhea?

    Science.gov (United States)

    Golparian, Daniel; Limnios, Athena; Whiley, David; Ohnishi, Makoto; Lahra, Monica M.; Tapsall, John W.

    2012-01-01

    Clinical resistance to the currently recommended extended-spectrum cephalosporins (ESCs), the last remaining treatment options for gonorrhea, is being reported. Gonorrhea may become untreatable, and new treatment options are crucial. We investigated the in vitro activity of ertapenem, relative to ceftriaxone, against N. gonorrhoeae isolates and the effects of ESC resistance determinants on ertapenem. MICs were determined using agar dilution technique or Etest for international reference strains (n = 17) and clinical N. gonorrhoeae isolates (n = 257), which included the two extensively drug-resistant (XDR) strains H041 and F89 and additional isolates with high ESC MICs, clinical ESC resistance, and other types of clinical high-level and multidrug resistance (MDR). Genetic resistance determinants for ESCs (penA, mtrR, and penB) were sequenced. In general, the MICs of ertapenem (MIC50 = 0.032 μg/ml; MIC90 = 0.064 μg/ml) paralleled those of ceftriaxone (MIC50 = 0.032 μg/ml; MIC90 = 0.125 μg/ml). The ESC resistance determinants mainly increased the ertapenem MIC and ceftriaxone MIC at similar levels. However, the MIC ranges for ertapenem (0.002 to 0.125 μg/ml) and ceftriaxone (gonorrhea, particularly for the currently identified ESC-resistant cases and possibly in a dual antimicrobial therapy regimen. However, further knowledge regarding the genetic determinants (and their evolution) conferring resistance to both antimicrobials, and clear correlates between genetic and phenotypic laboratory parameters and clinical treatment outcomes, is essential. PMID:22547617

  4. Replicative phenotyping adds value to genotypic resistance testing in heavily pre-treated HIV-infected individuals - the Swiss HIV Cohort Study

    Directory of Open Access Journals (Sweden)

    Martinetti Gladys

    2011-01-01

    Full Text Available Abstract Background Replicative phenotypic HIV resistance testing (rPRT uses recombinant infectious virus to measure viral replication in the presence of antiretroviral drugs. Due to its high sensitivity of detection of viral minorities and its dissecting power for complex viral resistance patterns and mixed virus populations rPRT might help to improve HIV resistance diagnostics, particularly for patients with multiple drug failures. The aim was to investigate whether the addition of rPRT to genotypic resistance testing (GRT compared to GRT alone is beneficial for obtaining a virological response in heavily pre-treated HIV-infected patients. Methods Patients with resistance tests between 2002 and 2006 were followed within the Swiss HIV Cohort Study (SHCS. We assessed patients' virological success after their antiretroviral therapy was switched following resistance testing. Multilevel logistic regression models with SHCS centre as a random effect were used to investigate the association between the type of resistance test and virological response (HIV-1 RNA Results Of 1158 individuals with resistance tests 221 with GRT+rPRT and 937 with GRT were eligible for analysis. Overall virological response rates were 85.1% for GRT+rPRT and 81.4% for GRT. In the subgroup of patients with >2 previous failures, the odds ratio (OR for virological response of GRT+rPRT compared to GRT was 1.45 (95% CI 1.00-2.09. Multivariate analyses indicate a significant improvement with GRT+rPRT compared to GRT alone (OR 1.68, 95% CI 1.31-2.15. Conclusions In heavily pre-treated patients rPRT-based resistance information adds benefit, contributing to a higher rate of treatment success.

  5. Polarized proton target with horizontal spin orientation

    International Nuclear Information System (INIS)

    Bunyatova, Eh.I.; Kiselev, Yu.F.; Kozlenko, N.G.

    1988-01-01

    Proton target, the polarization vector of which may be arbitrary oriented in horizontal plane relatively to the beam, is developed and tested. 70% value of polarization is obtained. 0.6 K temperature is acquired through 3 He pumping out continuous cycle. 1.2-propylene glycol - Cr(V) was used as working medium. Magnetic system is made in the form of Helmholtz sperconducting coils with working curren close to critical one. Target polarization is measured by NMR technique using original system of proton signal processing

  6. [Review] Polarization and Polarimetry

    Science.gov (United States)

    Trippe, Sascha

    2014-02-01

    Polarization is a basic property of light and is fundamentally linked to the internal geometry of a source of radiation. Polarimetry complements photometric, spectroscopic, and imaging analyses of sources of radiation and has made possible multiple astrophysical discoveries. In this article I review (i) the physical basics of polarization: electromagnetic waves, photons, and parameterizations; (ii) astrophysical sources of polarization: scattering, synchrotron radiation, active media, and the Zeeman, Goldreich-Kylafis, and Hanle effects, as well as interactions between polarization and matter (like birefringence, Faraday rotation, or the Chandrasekhar-Fermi effect); (iii) observational methodology: on-sky geometry, influence of atmosphere and instrumental polarization, polarization statistics, and observational techniques for radio, optical, and X/γ wavelengths; and (iv) science cases for astronomical polarimetry: solar and stellar physics, planetary system bodies, interstellar matter, astrobiology, astronomical masers, pulsars, galactic magnetic fields, gamma-ray bursts, active galactic nuclei, and cosmic microwave background radiation.

  7. Direct observation of hopping induced spin polarization current in oxygen deficient Co-doped ZnO by Andreev reflection technique

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kung-Shang; Huang, Tzu-Yu; Dwivedi, G.D. [Department of Physics, National Sun Yat-sen University, Kaohsiung, Taiwan (China); Lin, Lu-Kuei; Lee, Shang-Fan [Taiwan Institute of Physics, Academia Sinica, Taipei, Taiwan (China); Sun, Shih-Jye [Department of Applied Physics, National Kaohsiung University, Kaohsiung, Taiwan (China); Chou, Hsiung, E-mail: hchou@mail.nsysu.edu.tw [Department of Physics, National Sun Yat-sen University, Kaohsiung, Taiwan (China)

    2017-07-01

    Highlights: • Co-doped ZnO thin-films were grown with varying V{sub O} concentartion. • PCAR measurements were done to study the SPC. • High spin polarization was observed above a certain V{sub O} concentartion. • High V{sub O} samples provide a high density of completed percolation path. • This complete percolation path gives rise to high SPC. - Abstract: Oxygen vacancy induced ferromagnetic coupling in diluted magnetic oxide (DMO) semiconductors have been reported in several studies, but technologically more crucial spin-polarized current (SPC) is still under-developed in DMOs. Few studies have claimed that VRH mechanism can originate the SPC, but, how VRH mechanism associated with percolation path, is not clearly understood. We used Point-contact Andreev reflection (PCAR) technique to probe the SPC in Co-doped ZnO (CZO) films. Since the high resistance samples cause broadening in conductance(G)-voltage(V) curves, which may result in an unreliable evaluation of spin polarization, we include two extra parameters, (i) effective temperature and (ii) spreading resistance, for the simulation to avoid the uncertainty in extracting spin polarization. The effective G-V curves and higher spin polarization can be obtained above a certain oxygen vacancy concentration. The number of completed and fragmentary percolation paths is proportional to the concentration of oxygen vacancies. For low oxygen vacancy samples, the Pb-tip has a higher probability of covering fragmentary percolation paths than the complete ones, due to its small contact size. The completed paths may remain independent of one another and get polarized in different directions, resulting in lower spin-polarization value. High oxygen vacancy samples provide a high density of completed path, most of them link to one another by crossing over, and gives rise to high spin-polarization value.

  8. Worrisome trends in rising minimum inhibitory concentration values of antibiotics against methicillin resistant Staphylococcus aureus – Insights from a tertiary care center, South India

    Directory of Open Access Journals (Sweden)

    Nagasundaram Niveditha

    2015-11-01

    Conclusion: MIC creep was notably observed with vancomycin, and to some extent with tigecycline and linezolid. Selection pressure may result in creeping MICs, which may herald the emergence of resistant organisms.

  9. In Vitro Activity of Ertapenem versus Ceftriaxone against Neisseria gonorrhoeae Isolates with Highly Diverse Ceftriaxone MIC Values and Effects of Ceftriaxone Resistance Determinants: Ertapenem for Treatment of Gonorrhea?

    OpenAIRE

    Unemo, Magnus; Golparian, Daniel; Limnios, Athena; Whiley, David; Ohnishi, Makoto; Lahra, Monica M.; Tapsall, John W.

    2012-01-01

    Clinical resistance to the currently recommended extended-spectrum cephalosporins (ESCs), the last remaining treatment options for gonorrhea, is being reported. Gonorrhea may become untreatable, and new treatment options are crucial. We investigated the in vitro activity of ertapenem, relative to ceftriaxone, against N. gonorrhoeae isolates and the effects of ESC resistance determinants on ertapenem. MICs were determined using agar dilution technique or Etest for international reference strai...

  10. Polarization feedback laser stabilization

    Science.gov (United States)

    Esherick, P.; Owyoung, A.

    1987-09-28

    A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other. 4 figs.

  11. Polarization in Sagittarius A*

    OpenAIRE

    Bower, Geoffrey C.

    2000-01-01

    We summarize the current state of polarization observations of Sagittarius A*, the compact radio source and supermassive black hole candidate in the Galactic Center. These observations are providing new tools for understanding accretion disks, jets and their environments. Linear polarization observations have shown that Sgr A* is unpolarized at frequencies as high as 86 GHz. However, recent single-dish observations indicate that Sgr A* may have strong linear polarization at frequencies higher...

  12. Airborne Laser Polarization Sensor

    Science.gov (United States)

    Kalshoven, James, Jr.; Dabney, Philip

    1991-01-01

    Instrument measures polarization characteristics of Earth at three wavelengths. Airborne Laser Polarization Sensor (ALPS) measures optical polarization characteristics of land surface. Designed to be flown at altitudes of approximately 300 m to minimize any polarizing or depolarizing effects of intervening atmosphere and to look along nadir to minimize any effects depending on look angle. Data from measurements used in conjunction with data from ground surveys and aircraft-mounted video recorders to refine mathematical models used in interpretation of higher-altitude polarimetric measurements of reflected sunlight.

  13. Polarization at SLC

    International Nuclear Information System (INIS)

    Swartz, M.L.

    1988-07-01

    The SLAC Linear Collider has been designed to readily accommodate polarized electron beams. Considerable effort has been made to implement a polarized source, a spin rotation system, and a system to monitor the beam polarization. Nearly all major components have been fabricated. At the current time, several source and polarimeter components have been installed. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. It is expected that a beam polarization of 45% will be achieved with no loss in luminosity. 13 refs., 15 figs

  14. Adding value(s)

    DEFF Research Database (Denmark)

    Carré, David

    2015-01-01

    Most economic inquires revolve around agents making decisions. Getting the ‘best value’, it is assumed, drives such decisions: gaining most while risking least. This assumption has been debunked by showing that people does not always choose neither maximum benefit nor less risk (Kahneman & Tversky......, 1992). In response, behavioral economics (Camerer, 1999) has shown that agents have values other than optimization underpinning their decisions. Therefore, concerns arose regarding which values are guiding the agent but not about how such values became relevant for the agent. In this presentation, I...... will explore the consequences of shifting to the latter perspective, i.e. looking for the generative framework of values. Here I argue that economic behavior should also be seen as a sense-making process, guided by values that are chosen/rejected along with fellow human beings, in specific socio...

  15. An experiment of spectral induced polarization

    Directory of Open Access Journals (Sweden)

    L. Sambuelli

    1994-06-01

    Full Text Available A Spectral Induced Polarization (SIP survey was carried out in a mining test site in Sardinia (Italy. Measurements were developed along a profile by using an axial dipole-dipole array with 10 AB positions and 6 MN positions for cach AB. The amplitude and phase spectra of the apparent resistivity were acquired in the 0.25-4096 Hz frequeney range. The results obtained through the processing and inversion step seem to confirm that, with respect to the classical TD/FD Induced Polarization, SIP allows better discrimination of some important characteristics of mineral deposits such as mineral content and grain size.

  16. Role for risk-scoring tools in identifying resistant pathogens in pneumonia: reassessing the value of healthcare-associated pneumonia as a concept.

    Science.gov (United States)

    Shorr, Andrew F; Zilberberg, Marya D

    2015-05-01

    Resistant organisms remain a concern in patients presenting to hospital with pneumonia. Although in this setting the prevalence of various organisms such as methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa varies across the globe, patients infected with these pathogens are at increased risk for receiving an initially inappropriate antibiotic regimen - a major driver of mortality in all forms of pneumonia. The concept of healthcare-associated pneumonia (HCAP) was created to help clinicians identify persons at risk for infection with resistant pathogens, despite the onset of their infections occurring outside the hospital. However, it appears that HCAP, as currently defined, lacks adequate sensitivity and specificity for this purpose. Investigators have created various risk-scoring tools to stratify patients as to the likelihood that their infection is caused by a pathogen such as methicillin-resistant S. aureus or P. aeruginosa. These scores provide more precision at correctly segregating patients on the basis of the eventual recovery of resistant bacteria than does the HCAP syndrome. Most of these risk scores are easy to calculate and apply, and several have been externally validated. Physicians should consider adopting these tools in their approach to patients with pneumonia presenting to hospital.

  17. The Value of Value

    DEFF Research Database (Denmark)

    Sørensen, Asger

    and the regularity of such a phenomenon is both hard to verify and, if true, difficult to explain, it seems fair to say that since the Enlightenment, an approaching fin-de-siecle has brought an increased interest in matters concerning morality and ethics.1 The present peak has in public-political discourse and some...... parts of business ethics given prominence to especially one term, namely `value'. The question that interests me is the following: What does the articulation of ethics and morality in terms of values mean for ethics and morality as such. Or, to put the question in a more fashionably way: What...... is the value of value for morality and ethics?To make things a bit more precise, we can make use of the common distinction between ethics and morality, i.e. that morality is the immediate, collective and unconscious employment of morals, whereas ethics is the systematic, individual and conscious reflections...

  18. Modeling of permeate flux and mass transfer resistances in the reclamation of molasses wastewater by a novel gas-sparged nanofiltration

    International Nuclear Information System (INIS)

    Patel, Tejal Manish; Nath, Kaushik

    2014-01-01

    A semi-empirical model has been applied to predict the permeate flux and mass transfer resistances during the cross flow nanofiltration of molasses wastewater in flat-sheet module. The model includes laminar flow regime as well as flow in presence of gas sparging at two different gas velocities. Membrane hydraulic resistance (R m ), osmotic pressure resistance (R osm ) and the concentration polarization resistance (R cp ) were considered in series. The concentration polarization resistance was correlated to the operating conditions, namely, the feed concentration, the trans-membrane pressure difference and the cross flow velocity for a selected range of experiments. There was an appreciable reduction of concentration polarization resistance R cp spar in presence of gas sparging. Both the concentration polarization resistance R cp lam and osmotic pressure resistance R osm decreased with cross-flow velocity, but increased with feed concentration and the operating pressure. Experimental and theoretical permeate flux values as a function of cross flow velocity for both the cases, in the presence and absence of gas sparging, were also compared

  19. Terahertz polarization imaging

    NARCIS (Netherlands)

    Van der Valk, N.C.J.; Van der Marel, W.A.M.; Planken, P.C.M.

    2005-01-01

    We present a new method to measure the polarization state of a terahertz pulse by using a modified electrooptic sampling setup. To illustrate the power of this method, we show two examples in which the knowledge of the polarization of the terahertz pulse is essential for interpreting the results:

  20. Polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    The acceleration of polarized proton beams in circular accelerators is complicated by the presence of numerous depolarizing spin resonances. Careful and tedious minimization of polarization loss at each of these resonances allowed acceleration of polarized proton beams up to 22 GeV. It has been the hope that Siberian Snakes, which are local spin rotators inserted into ring accelerators, would eliminate these resonances and allow acceleration of polarized beams with the same ease and efficiency that is now routine for unpolarized beams. First tests at IUCF with a full Siberian Snake showed that the spin dynamics with a Snake can be understood in detail. The author now has results of the first tests of a partial Siberian Snake at the AGS, accelerating polarized protons to an energy of about 25 GeV. These successful tests of storage and acceleration of polarized proton beams open up new possibilities such as stored polarized beams for internal target experiments and high energy polarized proton colliders

  1. Polar Science Is Cool!

    Science.gov (United States)

    Weeks, Sophie

    2012-01-01

    Children are fascinated by the fact that polar scientists do research in extremely cold and dangerous places. In the Arctic they might be viewed as lunch by a polar bear. In the Antarctic, they could lose toes and fingers to frostbite and the wind is so fast it can rip skin off. They camp on ice in continuous daylight, weeks from any form of…

  2. Precision Polarization of Neutrons

    Science.gov (United States)

    Martin, Elise; Barron-Palos, Libertad; Couture, Aaron; Crawford, Christopher; Chupp, Tim; Danagoulian, Areg; Estes, Mary; Hona, Binita; Jones, Gordon; Klein, Andi; Penttila, Seppo; Sharma, Monisha; Wilburn, Scott

    2009-05-01

    Determining polarization of a cold neutron beam to high precision is required for the next generation neutron decay correlation experiments at the SNS, such as the proposed abBA and PANDA experiments. Precision polarimetry measurements were conducted at Los Alamos National Laboratory with the goal of determining the beam polarization to the level of 10-3 or better. The cold neutrons from FP12 were polarized using optically polarized ^3He gas as a spin filter, which has a highly spin-dependent absorption cross section. A second ^ 3He spin filter was used to analyze the neutron polarization after passing through a resonant RF spin rotator. A discussion of the experiment and results will be given.

  3. Optically polarized 3He

    Science.gov (United States)

    Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

    2018-01-01

    This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements. PMID:29503479

  4. Optically polarized 3He

    Science.gov (United States)

    Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

    2017-10-01

    This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements.

  5. Parallel Polarization State Generation.

    Science.gov (United States)

    She, Alan; Capasso, Federico

    2016-05-17

    The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security.

  6. Predictive Value of Prior Colonization and Antibiotic Use for Third-Generation Cephalosporin-Resistant Enterobacteriaceae Bacteremia in Patients With Sepsis

    NARCIS (Netherlands)

    Rottier, Wouter C.; Bamberg, Yara R. P.; Dorigo-Zetsma, J. Wendelien; van der Linden, Paul D.; Ammerlaan, Heidi S. M.; Bonten, Marc J. M.

    2015-01-01

    Background. To prevent inappropriate empiric antibiotic treatment in patients with bacteremia caused by third-generation cephalosporin (3GC)-resistant Enterobacteriaceae (3GC-R EB), Dutch guidelines recommend beta-lactam and aminoglycoside combination therapy or carbapenem monotherapy in patients

  7. Genomic selection models double the accuracy of predicted breeding values for bacterial cold water disease resistance compared to a traditional pedigree-based model in rainbow trout aquaculture

    Science.gov (United States)

    Previously we have shown that bacterial cold water disease (BCWD) resistance in rainbow trout can be improved using traditional family-based selection, but progress has been limited to exploiting only between-family genetic variation. Genomic selection (GS) is a new alternative enabling exploitation...

  8. Low prevalence of methicillin-resistant Staphylococcus aureus (MRSA) at hospital admission in the Netherlands: the value of search and destroy and restrictive antibiotic use

    NARCIS (Netherlands)

    Wertheim, H. F. L.; Vos, M. C.; Boelens, H. A. M.; Voss, A.; Vandenbroucke-Grauls, C. M. J. E.; Meester, M. H. M.; Kluytmans, J. A. J. W.; van Keulen, P. H. J.; Verbrugh, H. A.

    2004-01-01

    In the Netherlands, less than 1% of clinical isolates of Staphylococcus aureus are methicillin-resistant (MRSA). A national search and destroy policy prevents MRSA from becoming endemic. Some MRSA outbreaks cannot be related to patients at risk for MRSA carriage. This study was designed to measure

  9. Low prevalence of methicillin-resistant Staphylococcus aureus (MRSA) at hospital admission in the Netherlands: the value of search and destroy and restrictive antibiotic use.

    NARCIS (Netherlands)

    Wertheim, HF; Vos, MC; Boelens, HA; Voss, A; Vandenbroucke-Grauls, C.M.J.E.; Meester, MH; Kluytmans, J.A.; Keulen, van PH; Verbrugh, H.A.

    2004-01-01

    In the Netherlands, less than 1% of clinical isolates of Staphylococcus aureus are methicillin-resistant (MRSA). A national search and destroy policy prevents MRSA from becoming endemic. Some MRSA outbreaks cannot be related to patients at risk for MRSA carriage. This study was designed to measure

  10. Genome-enabled selection doubles the accuracy of predicted breeding values for bacterial cold water disease resistance compared to traditional family-based selection in rainbow trout aquaculture

    Science.gov (United States)

    We have shown previously that bacterial cold water disease (BCWD) resistance in rainbow trout can be improved using traditional family-based selection, but progress has been limited to exploiting only between-family genetic variation. Genomic selection (GS) is a new alternative enabling exploitation...

  11. Polarization of submillimetre lines from interstellar medium

    Science.gov (United States)

    Zhang, Heshou; Yan, Huirong

    2018-04-01

    Magnetic fields play important roles in many astrophysical processes. However, there is no universal diagnostic for the magnetic fields in the interstellar medium (ISM) and each magnetic tracer has its limitation. Any new detection method is thus valuable. Theoretical studies have shown that submillimetre fine-structure lines are polarized due to atomic alignment by ultraviolet photon-excitation, which opens up a new avenue to probe interstellar magnetic fields. We will, for the first time, perform synthetic observations on the simulated three-dimensional ISM to demonstrate the measurability of the polarization of submillimetre atomic lines. The maximum polarization for different absorption and emission lines expected from various sources, including star-forming regions are provided. Our results demonstrate that the polarization of submillimetre atomic lines is a powerful magnetic tracer and add great value to the observational studies of the submilimetre astronomy.

  12. Corrosion rate transients observed by linear polarization techniques at Zr-1%Nb alloy

    International Nuclear Information System (INIS)

    Beran, J.; Cerny, K.

    1997-01-01

    Momentary corrosion rate of Zr-1%Nb alloy during nonisothermal autoclave experiments at temperature up to 328 deg. C in various solutions was determined by T/R p values (T - absolute temperature, R p - polarization resistance), multiplied by temperature independent conversion factor. This factor was found by comparison of conventional corrosion loss evaluation with electrochemical measurements. Corrosion rate transients in boric acid solutions and in lithium hydroxide differed significantly. Great differences were also found in stabilized corrosion rates at the end of experiments. Temperature irregularities caused considerable changes in corrosion rate. (author). 5 refs, 5 figs, 1 tab

  13. The polarized platypus polarized neutron reflectometry made possible

    International Nuclear Information System (INIS)

    Saerbeck, Thomas

    2009-01-01

    Full text: The magnetic moment of the neutron, together with it's highly penetrating non destructive manner, make polarized neutron reflectometry an excellent tool to study magnetic phenomena across surfaces and interfaces of thin films. Unlike other magnetometry techniques which ordinarily yield only average magnetization values or, in case of probes with higher spatial resolution (e.g. electron microscopy or scanning tunnelling microscopy), show a high surface sensitivity, PNR together with magnetic x-ray scattering provides the ability to spatially resolve vector magnetization well beneath the surface [1] The ability to obtain vector magnetization profiles across interfaces and surfaces of thin films and multilayers offers the intriguing possibility to study systematically magnetic configurations and magnetic exchange interactions through intervening layers. In this paper we present the performance of the new polarization system installed on the time of flight neutron reflectometer PLATYPUS at ANSTO's Bragg Institute. The spin state of the neutrons is polarized and analysed by spatial separation of different neutron spin states using polarizing Fe/Si supermirrors before, and after the sample stage. The supermirrors have a large wavelength acceptance bandwidth of 3 A to 12 A. To control the desired spin direction of the incoming and reflected beam from the sample, two sets of RF spin flippers are installed. In the free space between the spin flippers and the sample stage the neutron spin direction is maintained by two sets of magnetic guide field coils. The new sample environment for studies of magnetic samples includes a 1 T electromagnet and a closed cycle refrigerator which gives access to a temperature range from 4K to 3 50 K .

  14. Morphology-dependent space charge polarization and dielectric relaxation of CdO nanomorphotypes

    Directory of Open Access Journals (Sweden)

    Paulose Thomas

    2016-12-01

    Full Text Available A versatile approach signifying the morphology-dependent dielectric polarization and relaxation mechanisms of cadmium oxide (CdO nanosphere, nanoflakes and nanoparallelepiped morphotypes as a function of frequency and temperature is presented. Variation of dielectric property is observed due to the changes of space charge/interfacial polarization resulting from the variations of surface to volume ratio of nanomorphology. Accordingly, colossal dielectric constant value has been observed in CdO nanosphere having larger surface to volume ratio. The order of dielectric constant (dc values observed for the present nanomorphologies is: dc of sphere > dc of flakes > dc of parallelepiped resembles the order of surface to volume ratios of the present morphologies respectively. The experimental data of complex impedance values are numerically fitted using theoretical models which provide the information of role of grain resistance on dielectric polarization and Cole–Cole type mechanism of dielectric relaxation process. The activation energies for electron transport are found to be 0.087eV for spheres, 0.074eV for flakes and 0.067 for parallelepiped nanomorphotypes of CdO. The dielectric and impedance spectroscopic analysis of the present material opens up wide scope for morphology-dependent tuning of nanomaterials for electrical applications.

  15. Layered and Laterally Constrained 2D Inversion of Time Domain Induced Polarization Data

    DEFF Research Database (Denmark)

    Fiandaca, Gianluca; Ramm, James; Auken, Esben

    transform of a complex resistivity forward response and the inversion extracts the spectral information of the time domain measures in terms of the Cole-Cole parameters. The developed forward code and inversion algorithm use the full time decay of the induced polarization response, together with an accurate...... algorithm retrieves consistent values for both the Cole-Cole parameters and the layer thicknesses and is a promising tool for identifying formation boundaries, e.g. in for discriminating sand and clay layers or pollution fans, due to the chargeability of these layers.......In a sedimentary environment, quasi-layered models often represent the actual geology more accurately than smooth minimum-structure models. We have developed a new layered and laterally constrained inversion algorithm for time domain induced polarization data. The algorithm is based on the time...

  16. Synthesis and Biological Evaluation of Polar Functionalities Containing Nitrodihydroimidazooxazoles as Anti-TB Agents.

    Science.gov (United States)

    Yempalla, Kushalava Reddy; Munagala, Gurunadham; Singh, Samsher; Kour, Gurleen; Sharma, Shweta; Chib, Reena; Kumar, Sunil; Wazir, Priya; Singh, G D; Raina, Sushil; Bharate, Sonali S; Khan, Inshad Ali; Vishwakarma, Ram A; Singh, Parvinder Pal

    2015-10-08

    Novel polar functionalities containing 6-nitro-2,3-dihydroimidazooxazole (NHIO) analogues were synthesized to produce a compound with enhanced solubility. Polar functionalities including sulfonyl, uridyl, and thiouridyl-bearing NHIO analogues were synthesized and evaluated against Mycobacterium tuberculosis (MTB) H37Rv. The aqueous solubility of compounds with MIC values ≤0.5 μg/mL were tested, and six compounds showed enhanced aqueous solubility. The best six compounds were further tested against resistant (Rif(R) and MDR) and dormant strains of MTB and tested for cytotoxicity in HepG2 cell line. Based on its overall in vitro characteristics and solubility profile, compound 6d was further shown to possess high microsomal stability, solubility under all tested biological conditions (PBS, SGF and SIF), and favorable oral in vivo pharmacokinetics and in vivo efficacy.

  17. Polarization at the SLC

    Energy Technology Data Exchange (ETDEWEB)

    Moffeit, K.C.

    1988-10-01

    The Stanford Linear collider was designed to accommodate polarized electron beams. Longitudinally polarized electrons colliding with unpolarized positrons at a center of mass energy near the Z/sup 0/ mass can be used as novel and sensitive probes of the electroweak process. A gallium arsenide based photon emission source will provide a beam of longitudinally polarized electrons of about 45 percent polarization. A system of bend magnets and a superconducting solenoid will be used to rotate the spins so that the polarization is preserved while the 1.21 GeV electrons are stored in the damping ring. Another set of bend magnets and two superconducting solenoids orient the spin vectors so that longitudinal polarization of the electrons is achieved at the collision point with the unpolarized positrons. A system to monitor the polarization based on Moller and Compton scattering will be used. Nearly all major components have been fabricated and tested. Subsystems of the source and polarimeters have been installed, and studies are in progress. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. 8 refs., 16 figs., 1 tab.

  18. Exploring Science Through Polar Exploration

    Science.gov (United States)

    Pfirman, S. L.; Bell, R. E.; Zadoff, L.; Kelsey, R.

    2003-12-01

    Exploring the Poles is a First Year Seminar course taught at Barnard College, Columbia University. First Year Seminars are required of incoming students and are designed to encourage critical analysis in a small class setting with focused discussion. The class links historical polar exploration with current research in order to: introduce non-scientists to the value of environmental science through polar literature; discuss issues related to venturing into the unknown that are of relevance to any discipline: self-reliance, leadership, preparation, decisions under uncertainty; show students the human face of science; change attitudes about science and scientists; use data to engage students in exploring/understanding the environment and help them learn to draw conclusions from data; integrate research and education. These goals are met by bringing analysis of early exploration efforts together with a modern understanding of the polar environment. To date to class has followed the efforts of Nansen in the Fram, Scott and Amundsen in their race to the pole, and Shackleton's Endurance. As students read turn-of-the-century expedition journals, expedition progress is progressively revealed on an interactive map showing the environmental context. To bring the exploration process to life, students are assigned to expedition teams for specific years and the fates of the student "expeditions" are based on their own decisions. For example, in the Arctic, they navigate coastal sea ice and become frozen into the ice north of Siberia, re-creating Nansen's polar drift. Fates of the teams varied tremendously: some safely emerged at Fram Strait in 4 years, while others nearly became hopelessly lost in the Beaufort Gyre. Students thus learn about variability in the current polar environment through first hand experience, enabling them to appreciate the experiences, decisions, and, in some cases, the luck, of polar explorers. Evaluation by the Columbia Center for New Media, Teaching

  19. Polarized atomic beams for targets

    International Nuclear Information System (INIS)

    Grueebler, W.

    1984-01-01

    The basic principle of the production of polarized atomic hydrogen and deuterium beams are reviewed. The status of the present available polarization, density and intensity are presented. The improvement of atomic beam density by cooling the hydrogen atoms to low velocity is discussed. The possible use of polarized atomic beams as targets in storage rings is shown. It is proposed that polarized atomic beams can be used to produce polarized gas targets with high polarization and greatly improved density

  20. Polarized scintillator targets

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.; Mango, S.

    2000-05-01

    The hydrogen nuclei in an organic scintillator have been polarized to more than 80% and the deuterons in its fully deuterated version to 24%. The scintillator, doped with TEMPO, has been polarized dynamically in a field of 2.5 T in a vertical dilution refrigerator in which a plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat. Sizeable solid samples with acceptable optical properties and light output have been prepared and successfully operated as "live" polarized targets in nuclear physics experiments.

  1. Polarized scintillator targets

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, B. van den E-mail: vandenbrandt@psi.ch; Bunyatova, E.I.; Hautle, P.; Konter, J.A.; Mango, S

    2000-05-21

    The hydrogen nuclei in an organic scintillator have been polarized to more than 80% and the deuterons in its fully deuterated version to 24%. The scintillator, doped with TEMPO, has been polarized dynamically in a field of 2.5 T in a vertical dilution refrigerator in which a plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat. Sizeable solid samples with acceptable optical properties and light output have been prepared and successfully operated as 'live' polarized targets in nuclear physics experiments.

  2. Heidelberg polarized alkali source

    International Nuclear Information System (INIS)

    Kraemer, D.; Steffens, E.; Jaensch, H.; Philipps Universitaet, Marburg, Germany)

    1984-01-01

    A new atomic beam type polarized alkali ion source has been installed at Heidelberg. In order to improve the beam polarization considerably optical pumping is applied in combination with an adiabatic medium field transition which results in beams in single hyperfine sublevels. The m state population is determined by laser-induced fluorescence spectroscopy. Highly polarized beams (P/sub s/ > 0.9, s = z, zz) with intensities of 30 to 130 μA can be extracted for Li + and Na + , respectively

  3. Polarization measurement in the COMPASS polarized target

    CERN Document Server

    Kondo, K; Baum, G; Berglund, P; Doshita, N; Gautheron, F; Görtz, S; Hasegawa, T; Horikawa, N; Ishimoto, S; Iwata, T; Kisselev, Yu V; Koivuniemi, J H; Le Goff, J M; Magnon, A; Meyer, W; Reicherz, G; Matsuda, T

    2004-01-01

    Continuous wave nuclear magnetic resonance (NMR) is used to determine the target polarization in the COMPASS experiment. The system is made of the so-called Liverpool Q-meters, Yale-cards, and VME modules for data taking and system controlling. In 2001 the NMR coils were embedded in the target material, while in 2002 and 2003 the coils were mounted on the outer surface of the target cells to increase the packing factor of the material. Though the error of the measurement became larger with the outer coils than with the inner coils, we have performed stable measurements throughout the COMPASS run time for 3 years. The maximum polarization was +57% and -53% as the average in the target cells.

  4. DUAL POLARIZATION ANTENNA ARRAY WITH VERY LOW CROSS POLARIZATION AND LOW SIDE LOBES

    DEFF Research Database (Denmark)

    1997-01-01

    formation of grating lobes are inhibited in selected directions of the radiation and cross polarization within the main lobe is suppressed at least 30 dB below the main lobe peak value. According to a preferred embodiment of the invention, the antenna elements of the antenna array comprise probe-fed patches......The present invention relates to an antenna array adapted to radiate or receive electromagnetic waves of one or two polarizations with very low cross polarization and low side lobes. An antenna array comprising many antenna elements, e.g. more than ten antenna elements, is provided in which...

  5. Dynamic nuclear spin polarization

    Energy Technology Data Exchange (ETDEWEB)

    Stuhrmann, H.B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany)

    1996-11-01

    Polarized neutron scattering from dynamic polarized targets has been applied to various hydrogenous materials at different laboratories. In situ structures of macromolecular components have been determined by nuclear spin contrast variation with an unprecedented precision. The experiments of selective nuclear spin depolarisation not only opened a new dimension to structural studies but also revealed phenomena related to propagation of nuclear spin polarization and the interplay of nuclear polarisation with the electronic spin system. The observation of electron spin label dependent nuclear spin polarisation domains by NMR and polarized neutron scattering opens a way to generalize the method of nuclear spin contrast variation and most importantly it avoids precontrasting by specific deuteration. It also likely might tell us more about the mechanism of dynamic nuclear spin polarisation. (author) 4 figs., refs.

  6. Time Domain Induced Polarization

    DEFF Research Database (Denmark)

    Fiandaca, Gianluca; Auken, Esben; Christiansen, Anders Vest

    2012-01-01

    Time-domain-induced polarization has significantly broadened its field of reference during the last decade, from mineral exploration to environmental geophysics, e.g., for clay and peat identification and landfill characterization. Though, insufficient modeling tools have hitherto limited the use...... of time-domaininduced polarization for wider purposes. For these reasons, a new forward code and inversion algorithm have been developed using the full-time decay of the induced polarization response, together with an accurate description of the transmitter waveform and of the receiver transfer function......%. Furthermore, the presence of low-pass filters in time-domain-induced polarization instruments affects the early times of the acquired decays (typically up to 100 ms) and has to be modeled in the forward response to avoid significant loss of resolution. The developed forward code has been implemented in a 1D...

  7. Polarized proton colliders

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. This will allow the study of the spin structure of the proton and also the verification of the many well documented expectations of spin effects in perturbative QCD and parity violation in W and Z production. Proposals for polarized proton acceleration for several high energy colliders have been developed. A partial Siberian Snake in the AGS has recently been successfully tested and full Siberian Snakes, spin rotators, and polarimeters for RHIC are being developed to make the acceleration of polarized beams to 250 GeV possible. This allows for the unique possibility of colliding two 250 GeV polarized proton beams at luminosities of up to 2 x 10 32 cm -2 s -1

  8. Plasma polarization spectroscopy

    International Nuclear Information System (INIS)

    Iwamae, Atsushi; Horimoto, Yasuhiro; Fujimoto, Takashi; Hasegawa, Noboru; Sukegawa, Kouta; Kawachi, Tetsuya

    2005-01-01

    The electron velocity distribution function (EVDF) in plasma can be anisotropic in laser-produced plasmas. We have developed a new technique to evaluate the polarization degree of the emission lines in the extreme vacuum ultra violet wavelength region. The polarization of the emission lines and the continuums from the lithium-like nitrogen and from helium- and hydrogen-like carbon in recombining plasma is evaluated. Particle simulation in the velocity space gives the time scale for relaxation of anisotropic EVDFs. (author)

  9. Ultracold Polar Molecules

    Science.gov (United States)

    2016-04-01

    AFRL-AFOSR-UK-TR-2016-0005 Ultracold Polar Molecules Jeremy Hutson UNIVERSITY OF DURHAM Final Report 04/01/2016 DISTRIBUTION A: Distribution approved...DATES COVERED (From - To) 15-Jan-2010 to 14-Jul-2015 4. TITLE AND SUBTITLE Final Report on Grant FA8655-10-1-3033 on Ultracold Polar Molecules 5a...formation of ultracold 87RbCs molecules in their rovibrational ground state by magnetoassociation followed by STIRAP, resulting in 14 papers acknowledging

  10. Potentiodynamic polarization study of the corrosion behavior of palladium-silver dental alloys.

    Science.gov (United States)

    Sun, Desheng; Brantley, William A; Frankel, Gerald S; Heshmati, Reza H; Johnston, William M

    2018-04-01

    Although palladium-silver alloys have been marketed for over 3 decades for metal-ceramic restorations, understanding of the corrosion behavior of current alloys is incomplete; this understanding is critical for evaluating biocompatibility and clinical performance. The purpose of this in vitro study was to characterize the corrosion behavior of 3 representative Pd-Ag alloys in simulated body fluid and oral environments and to compare them with a high-noble Au-Pd alloy. The study obtained values of important electrochemical corrosion parameters, with clinical relevance, for the rational selection of casting alloys. The room temperature in vitro corrosion characteristics of the 3 Pd-Ag alloys and the high-noble Au-Pd alloy were evaluated in 0.9% NaCl, 0.09% NaCl, and Fusayama solutions. After simulated porcelain firing heat treatment, 5 specimens of each alloy were immersed in the electrolytes for 24 hours. For each specimen, the open-circuit potential (OCP) was first recorded, and linear polarization was then performed from -20 mV to +20 mV (versus OCP) at a rate of 0.125 mV/s. Cyclic polarization was subsequently performed on 3 specimens of each alloy from -300 mV to +1000 mV and back to -300 mV (versus OCP) at a scanning rate of 1 mV/s. The differences in OCP and corrosion resistance parameters (zero-current potential and polarization resistance) among alloys and electrolyte combinations were compared with the 2-factor ANOVA (maximum-likelihood method) with post hoc Tukey adjustments (α=.05). The 24-hour OCPs and polarization resistance values of the 3 Pd-Ag alloys and the Au-Pd alloy were not significantly different (P=.233 and P=.211, respectively) for the same electrolyte, but significant differences were found for corrosion test results in different electrolytes (Palloy and electrolyte (P=.249 and P=.713, respectively). The 3 Pd-Ag silver alloys appeared to be resistant to chloride ion corrosion, and passivation and de-alloying were identified for these

  11. Validity of Wearable Activity Monitors during Cycling and Resistance Exercise.

    Science.gov (United States)

    Boudreaux, Benjamin D; Hebert, Edward P; Hollander, Daniel B; Williams, Brian M; Cormier, Corinne L; Naquin, Mildred R; Gillan, Wynn W; Gusew, Emily E; Kraemer, Robert R

    2018-03-01

    The use of wearable activity monitors has seen rapid growth; however, the mode and intensity of exercise could affect the validity of heart rate (HR) and caloric (energy) expenditure (EE) readings. There is a lack of data regarding the validity of wearable activity monitors during graded cycling regimen and a standard resistance exercise. The present study determined the validity of eight monitors for HR compared with an ECG and seven monitors for EE compared with a metabolic analyzer during graded cycling and resistance exercise. Fifty subjects (28 women, 22 men) completed separate trials of graded cycling and three sets of four resistance exercises at a 10-repetition-maximum load. Monitors included the following: Apple Watch Series 2, Fitbit Blaze, Fitbit Charge 2, Polar H7, Polar A360, Garmin Vivosmart HR, TomTom Touch, and Bose SoundSport Pulse (BSP) headphones. HR was recorded after each cycling intensity and after each resistance exercise set. EE was recorded after both protocols. Validity was established as having a mean absolute percent error (MAPE) value of ≤10%. The Polar H7 and BSP were valid during both exercise modes (cycling: MAPE = 6.87%, R = 0.79; resistance exercise: MAPE = 6.31%, R = 0.83). During cycling, the Apple Watch Series 2 revealed the greatest HR validity (MAPE = 4.14%, R = 0.80). The BSP revealed the greatest HR accuracy during resistance exercise (MAPE = 6.24%, R = 0.86). Across all devices, as exercise intensity increased, there was greater underestimation of HR. No device was valid for EE during cycling or resistance exercise. HR from wearable devices differed at different exercise intensities; EE estimates from wearable devices were inaccurate. Wearable devices are not medical devices, and users should be cautious when using these devices for monitoring physiological responses to exercise.

  12. Hsp Polarization Verification

    Science.gov (United States)

    Bless, Robert

    1991-07-01

    This proposal defines the procedure for determining the instrumental polarization of the polarimetric IDT (IDT#1, POL) on the HSP. 1 of 2 unpolarized standard stars wil be observed using various filter-polarizer combinations. These observations will permit the instrumental polarization to be calibrated. The instrumental polarization must be determined to a high precision in order to vectoriallly remove it from HSP polarization observations to determine the actual astronomical polarization. Final run of proposal will look at one of 2 possible stars previously observed to get another look at the throughput. Revision History: Mark H. Slovak 8/30/88 Translated to V2 proposal instructions (RPSS V6.2) S. Laurent 1/20/89 Updated: Sally Laurent 2/24/89, 3/20/89, 4/13/89, 5/12/89 Modified: P. Stanley 1/15/90 - change to use CTA selected targets only; Fixes for aberration problem - SALM 7/30/90; Based on SV/HSP 1386. New submission changed targets and revised scheduling strategy. Revised: 26 Aug 92 J. Dolan, L. Walter, P. Reppert want to re-run the proposal (3985) one last time to bring down errors.

  13. Bronchial histamine challenge in the diagnosis of asthma. The predictive value of changes in airway resistance determined by the interrupter method

    DEFF Research Database (Denmark)

    Madsen, F; Holstein-Rathlou, N H; Frølund, L

    1986-01-01

    The predictive value of a bronchial challenge with histamine was determined in a prospective survey on a population with a high prevalence of asthma (0.62). Without knowledge of the bronchial responsiveness 133 patients were classified as asthmatics (83) or non-asthmatics (50) according....../ml the predictive value of a negative test in the diagnosis of asthma was increased to 0.81. The interrupter technique is suitable for diagnostic purposes in the detection and exclusion of bronchial asthma....

  14. Resistência à mudança organizacional: perspectiva valorativa e organizacional = Resistance to organizational change: values and organizational perspective = Resistencia al cambio organizacional: perspectiva valorativos y organizacionales

    Directory of Open Access Journals (Sweden)

    Freires, Dayse Ayres do Nascimento

    2014-01-01

    Full Text Available Este estudo objetivou conhecer os correlatos valorativos e organizacionais da resistência à mudança organizacional, propondo um modelo explicativo que considera o desempenho autopercebido como variável critério. Considerou-se uma amostra de conveniência de 227 funcionários de uma empresa pública de João Pessoa, que tinham idade média de 40 anos, a maioria do sexo masculino (83,3%. Estes responderam a Escala de Resistência à Mudança Organizacional, Escala de Clima Organizacional, Questionários dos Valores Básicos, Escala de Autoavaliação de Desempenho e perguntas demográficas. Os resultados indicaram que os valores idealistas e o clima organizacional explicaram a resistência à mudança organizacional, que predisse o desempenho autopercebido. Concluiu-se que este modelo pode ser útil para compreender a aceitação das mudanças no contexto organizacional, favorecendo práticas de gestão que considerem variáveis psicológicas e organizacionais dos trabalhadores

  15. The Value of Value

    DEFF Research Database (Denmark)

    Sørensen, Asger

    As a social scientist of ethics and morality, Luhmann has noticed the ethical wave that has recently swept across the western world, and states that this particular kind of wave seems to have a wavelength of about one hundred years (cf. Luhmann 1989: 9 ff.). Even though the frequency and the regu......As a social scientist of ethics and morality, Luhmann has noticed the ethical wave that has recently swept across the western world, and states that this particular kind of wave seems to have a wavelength of about one hundred years (cf. Luhmann 1989: 9 ff.). Even though the frequency...... and the regularity of such a phenomenon is both hard to verify and, if true, difficult to explain, it seems fair to say that since the Enlightenment, an approaching fin-de-siecle has brought an increased interest in matters concerning morality and ethics.1 The present peak has in public-political discourse and some...... parts of business ethics given prominence to especially one term, namely `value'. The question that interests me is the following: What does the articulation of ethics and morality in terms of values mean for ethics and morality as such. Or, to put the question in a more fashionably way: What...

  16. Polarized Light Microscopy

    Science.gov (United States)

    Frandsen, Athela F.

    2016-01-01

    Polarized light microscopy (PLM) is a technique which employs the use of polarizing filters to obtain substantial optical property information about the material which is being observed. This information can be combined with other microscopy techniques to confirm or elucidate the identity of an unknown material, determine whether a particular contaminant is present (as with asbestos analysis), or to provide important information that can be used to refine a manufacturing or chemical process. PLM was the major microscopy technique in use for identification of materials for nearly a century since its introduction in 1834 by William Fox Talbot, as other techniques such as SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared spectroscopy), XPD (X-ray Powder Diffraction), and TEM (Transmission Electron Microscopy) had not yet been developed. Today, it is still the only technique approved by the Environmental Protection Agency (EPA) for asbestos analysis, and is often the technique first applied for identification of unknown materials. PLM uses different configurations in order to determine different material properties. With each configuration additional clues can be gathered, leading to a conclusion of material identity. With no polarizing filter, the microscope can be used just as a stereo optical microscope, and view qualities such as morphology, size, and number of phases. With a single polarizing filter (single polars), additional properties can be established, such as pleochroism, individual refractive indices, and dispersion staining. With two polarizing filters (crossed polars), even more can be deduced: isotropy vs. anisotropy, extinction angle, birefringence/degree of birefringence, sign of elongation, and anomalous polarization colors, among others. With the use of PLM many of these properties can be determined in a matter of seconds, even for those who are not highly trained. McCrone, a leader in the field of polarized light microscopy, often

  17. The evolution of tensor polarization

    International Nuclear Information System (INIS)

    Huang, H.; Lee, S.Y.; Ratner, L.

    1993-01-01

    By using the equation of motion for the vector polarization, the spin transfer matrix for spin tensor polarization, the spin transfer matrix for spin tensor polarization is derived. The evolution equation for the tensor polarization is studied in the presence of an isolate spin resonance and in the presence of a spin rotor, or snake

  18. Circular polarization measurements with a Ge(Li) detector

    DEFF Research Database (Denmark)

    Kopecký, J.; Warming, Inge Elisabeth

    1969-01-01

    This paper presents the results obtained in measurements of the degree of circular polarization of gamma transitions to bound states of 33S, 36Cl, 49Ti, 56Mn, 57Fe, 60Co and 64Cu following the capture of polarized thermal neutrons. Spin values have been determined on the basis of these results....

  19. Effect of spin polarization on the structural properties and bond ...

    Indian Academy of Sciences (India)

    coupled to semi-empirical hardness theory proved effective in hardness prediction for the metal borides which agree well with the experimental values. These results would help to gain insight into the spin-polarized effect on the structural and bond hardness. Keywords. Iron boride; DFT; spin polarized; critical pressure; ...

  20. Direct Probes of Linearly Polarized Gluons inside Unpolarized Hadrons

    NARCIS (Netherlands)

    Boer, D.; Brodsky, S. J.; Mulders, P.J.G.; Pisano, C.

    2011-01-01

    We show that linearly polarized gluons inside unpolarized hadrons can be directly probed in jet or heavy quark pair production in electron-hadron collisions. We discuss the simplest cos2 asymmetries and estimate their maximal value, concluding that measurements of the unknown linearly polarized

  1. Multiscale Electrochemical Investigation of the Corrosion Resistance of Various Alloys Used in Dental Prostheses

    Science.gov (United States)

    Iacoban, Sorin; Mareci, Daniel; Bolat, Georgiana; Munteanu, Corneliu; Souto, Ricardo Manuel

    2015-04-01

    The electrochemical behavior of Ag-Pd (Paliag), Ni-Cr (Heraenium NA), and Co-Cr (Heraenium CE) alloys used in dental prosthetics construction of crowns and bridges was studied in 0.9 pct NaCl solution at 298 K (25 °C). The localized electrochemical characteristics related to corrosion resistance and eventual breakdown of the protecting oxide layers were investigated by scanning electrochemical microscopy (SECM), whereas potentiodynamic polarization and electrochemical impedance spectroscopy techniques were employed to establish oxide stability. When the corrosion resistance of the alloys was evaluated by means of the corrosion current value determined around their corresponding open circuit potential in 0.9 pct NaCl solution, good protection can be expected resulting from their spontaneous passivation (low current densities in the order of tenths of μA cm-2). The polarization resistance of all the samples increased with immersion time, in the sequence Ag-Pd Ag-Pd instead.

  2. Polarized Electrons at Jefferson Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, C.K.

    1997-12-31

    The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously.initial operational experience with the polarized source will be presented.

  3. Polarized electrons at Jefferson laboratory

    International Nuclear Information System (INIS)

    The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously. Initial operational experience with the polarized source will be presented

  4. Magnetization reversal of ferromagnetic nanoparticles induced by a stream of polarized electrons

    Energy Technology Data Exchange (ETDEWEB)

    Kozhushner, M.A.; Gatin, A.K.; Grishin, M.V.; Shub, B.R. [Semenov Institute of Chemical Physics of RAS, 4, Kosygin Street, Moscow 119991 (Russian Federation); Kim, V.P.; Khomutov, G.B. [Faculty of Physics, Lomonosov Moscow State University, Lenin Gory 1-2, Moscow 119991 (Russian Federation); Ilegbusi, O.J. [University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816-2450 (United States); Trakhtenberg, L.I. [Semenov Institute of Chemical Physics of RAS, 4, Kosygin Street, Moscow 119991 (Russian Federation)

    2016-09-15

    The remagnetization of ferromagnetic Fe{sub 3}O{sub 4} nanoparticles of several thousand cubic nanometers by spin-polarized current is investigated. For this purpose, magnetite nanoparticles are synthesized and deposited on a conductive nonmagnetic substrate. The remagnetization is conducted in high-vacuum scanning tunneling microscope (STM). The STM tip from magnetized iron wire constitutes one electrode while the ferromagnetic nanoparticle on the graphite surface represents the second electrode. The measured threshold value of remagnetization current (I{sub thresh}=9 nA) is the lowest value of current at which remagnetization occurs. The change in nanoparticle magnetization is detected by the effect of giant magnetic resistance, specifically, the dependence of the weak polarized current (Ipolarized current on magnetic moment of small ferromagnetic nanoclusters. The peculiarities of size dependence of the observed effects are explained. - Highlights: • Ferromagnetic nanoparticle in STM with ferromagnetic tip. • Change of the direction of nanoparticle magnetization by current I>I{sub cr}=9 nA. • GMR effect used to control change of magnetization.

  5. Polar low monitoring

    Science.gov (United States)

    Bobylev, Leonid; Zabolotskikh, Elizaveta; Mitnik, Leonid

    2010-05-01

    Polar lows are intense mesoscale atmospheric low pressure weather systems, developing poleward of the main baroclinic zone and associated with high surface wind speeds. Small size and short lifetime, sparse in-situ observations in the regions of their development complicate polar low study. Our knowledge of polar lows and mesocyclones has come almost entirely during the period of satellite remote sensing since, by virtue of their small horizontal scale, it was rarely possible to analyse these lows on conventional weather charts using only the data from the synoptic observing network. However, the effects of intense polar lows have been felt by coastal communities and seafarers since the earliest times. These weather systems are thought to be responsible for the loss of many small vessels over the centuries, although the nature of the storms was not understood and their arrival could not be predicted. The actuality of the polar low research is stipulated by their high destructive power: they are a threat to such businesses as oil and gas exploration, fisheries and shipping. They could worsen because of global warming: a shrinking of sea ice around the North Pole, which thawed to its record minimum in the summer of 2007, is likely to give rise to more powerful storms that form only over open water and can cause hurricane-strength winds. Therefore, study of polar lows, their timely detection, tracking and forecasting represents a challenge for today meteorology. Satellite passive microwave data, starting from Special Sensor Microwave Imager (SSM/I) onboard Defense Meteorological Satellite Program (DMSP) satellite, remain invaluable source of regularly available remotely sensed data to study polar lows. The sounding in this spectral range has several advantages in comparison with observations in visible and infrared ranges and Synthetic Aperture Radar (SAR) data: independence on day time and clouds, regularity and high temporal resolution in Polar Regions. Satellite

  6. Polarized protons at RHIC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1990-12-01

    The Physics case is presented for the use of polarized protons at RHIC for one or two months each year. This would provide a facility with polarizations of approx-gt 50% high luminosity ∼2.0 x 10 32 cm -2 s -1 , the possibility of both longitudinal and transverse polarization at the interaction regions, and frequent polarization reversal for control of systematic errors. The annual integrated luminosity for such running (∼10 6 sec per year) would be ∫ Ldt = 2 x 10 38 cm -2 -- roughly 20 times the total luminosity integrated in ∼ 10 years of operation of the CERN Collider (∼10 inverse picobarns, 10 37 cm -2 ). This facility would be unique in the ability to perform parity-violating measurements and polarization test of QCD. Also, the existence of p-p collisions in a new energy range would permit the study of ''classical'' reactions like the total cross section and elastic scattering, etc., and serve as a complement to measurements from p-bar p colliders. 11 refs

  7. The Bochum Polarized Target

    International Nuclear Information System (INIS)

    Reicherz, G.; Goertz, S.; Harmsen, J.; Heckmann, J.; Meier, A.; Meyer, W.; Radtke, E.

    2001-01-01

    The Bochum 'Polarized Target' group develops the target material 6 LiD for the COMPASS experiment at CERN. Several different materials like alcohols, alcanes and ammonia are under investigation. Solid State Targets are polarized in magnetic fields higher than B=2.5T and at temperatures below T=1K. For the Dynamic Nuclear Polarization process, paramagnetic centers are induced chemically or by irradiation with ionizing beams. The radical density is a critical factor for optimization of polarization and relaxation times at adequate magnetic fields and temperatures. In a high sensitive EPR--apparatus, an evaporator and a dilution cryostat with a continuous wave NMR--system, the materials are investigated and optimized. To improve the polarization measurement, the Liverpool NMR-box is modified by exchanging the fixed capacitor for a varicap diode which not only makes the tuning very easy but also provides a continuously tuned circuit. The dependence of the signal area upon the circuit current is measured and it is shown that it follows a linear function

  8. In-line Fiber Polarizer

    OpenAIRE

    Perumalsamy, Priya

    1998-01-01

    Polarizers and polarization devices are important components in fiber optic communication and sensor systems. There is a growing need for efficient low loss components that are compatible with optical fibers. An all fiber in-line polarizer is a more desirable alternative that could be placed at appropriate intervals along communication links. An in-line fiber polarizer was fabricated and tested. The in-line fiber polarizer operates by coupling optical energy propagatin...

  9. Insulin Resistance Distribution and Cut-Off Value in Koreans from the 2008-2010 Korean National Health and Nutrition Examination Survey

    Science.gov (United States)

    Yun, Kyung-Jin; Han, Kyungdo; Kim, Mee Kyoung; Park, Yong-Moon; Baek, Ki-Hyun; Song, Ki-Ho; Kwon, Hyuk-Sang

    2016-01-01

    Background We sought to identify the distribution and cut-off value of the ‘homeostasis model assessment of insulin resistance’ (HOMA-IR) according to gender and menopausal status for metabolic syndrome in Koreans. Methods Data were from the Korean National Health and Nutrition Examination Survey in 2008–2010. The subjects included adults aged 20 years or older. We excluded participants who had diabetes or fasting serum glucose ≥ 7 mmol/L. Finally, 11,121 subjects (4,911 men, 3,597 premenopausal women, 2,613 postmenopausal women) were enrolled. The modified Adult Treatment Panel III criteria were used to define metabolic syndrome. Results The mean HOMA-IR was 2.11 (2.07–2.15) for men, 2.0 (1.97–2.04) for premenopausal women, and 2.14 (2.2–2.19) for postmenopausal women. The first cut-off values in men, premenopausal women, and postmenopausal women were 2.23 (sensitivity 70.6%, specificity 66.9%), 2.39 (sensitivity 72.3%, specificity 76.4%), and 2.48 (sensitivity 51.9%, specificity 80.2%), respectively. Based on the first HOMA-IR cut-off value, the prevalence of metabolic syndrome was 22.9% in men, 13.7% in premenopausal women, and 51.6% in postmenopausal women. The second cut-off value was around 3.2 in all three groups. Based on the second HOMA-IR cut-off value, the prevalence of metabolic syndrome was 50.8% in men, 42.5% in premenopausal women, and 71.6% in postmenopausal women. Conclusion In conclusion, the first cut-off values for HOMA-IR were 2.2–2.5 and the second cut-off value was 3.2 in Korea. The distribution of HOMA-IR showed differences according to gender and menopausal status. When we apply HOMA-IR, we should consider gender, menopausal status, and the prevalence of metabolic syndrome. PMID:27128847

  10. Conceptual design and first results of a combined electrical resistivity and induced polarization monitoring at the Aiguille du Midi rock permafrost summit (Mont Blanc Massif, French/Italian Alps)

    Science.gov (United States)

    Krautblatter, M.; Verleysdonk, S.; Flores-Orozco, A.; Kemna, A.; Deline, P.; Ravanel, L.; Pogliotti, P.; Coviello, V.; Malet, E.

    2009-04-01

    Monitoring of systemic changes in high mountain rock permafrost proves to be of increasing significance. The association with ongoing and future climate change raises the need for monitoring schemes to enable modelling of future scenarios. Due to the high degree of tourist utilisation and the good accessibility via cable car, the Aiguille du Midi represents the ideal premises to establish a long-term monitoring site. At 3842 m a.s.l. the steep granite summit offers access to all aspects in combination with persistent ice in the rock face and different rock mechanical settings. The geophysical monitoring presented here integrates into the framework of the French-Italian PERMAdataROC project and is presently considered for the EU co-funded project PermaNET (Permafrost long-term monitoring network: www.permanet-alpinespace.eu). ERT and IP were conducted along three transects at the Aiguille du Midi in December 2008. Two transects were installed along galleries and in the rock faces that are accessible from the public platform at 3770 m a.s.l.. A further transect was installed by abseiling from the summit to the steep north and south face. The southern limb of the transect goes past the meteorological station installed in a vertical rock section. All transects were measured with a Syscal Pro device with high voltages of 800 V and we applied 48 steel electrodes per transect placed firmly in drilled holes. For optimum coverage we developed a high-resolution ERT protocol with approximately 3000 dipole-dipole measurements per array and 200 cross-borehole type measurements. Time domain IP was measured alongside to check chargeability of clefts with fine-grained fillings. Simultaneously, a survey of all important clefts was made to reference chargeability values. Both ERT and IP measurements were recorded in normal and reciprocal orientation and are used to define the error levels inherent in the measurements. A smoothness-constrained Occam's inversion is then adjusted to

  11. Multiple negative differential resistance devices with ultra-high peak-to-valley current ratio for practical multi-valued logic and memory applications

    Science.gov (United States)

    Shin, Sunhae; Rok Kim, Kyung

    2015-06-01

    In this paper, we propose a novel multiple negative differential resistance (NDR) device with ultra-high peak-to-valley current ratio (PVCR) over 106 by combining tunnel diode with a conventional MOSFET, which suppresses the valley current with transistor off-leakage level. Band-to-band tunneling (BTBT) in tunnel junction provides the first peak, and the second peak and valley are generated from the suppression of diffusion current in tunnel diode by the off-state MOSFET. The multiple NDR curves can be controlled by doping concentration of tunnel junction and the threshold voltage of MOSFET. By using complementary multiple NDR devices, five-state memory is demonstrated only with six transistors.

  12. Dispersing surface-modified imogolite nanotubes in polar and non-polar solvents

    Science.gov (United States)

    Li, Ming; Brant, Jonathan A.

    2018-02-01

    Furthering the development of nanocomposite structures, namely membranes for water treatment applications, requires that methods be developed to ensure nanoparticle dispersion in polar and non-polar solvents, as both are widely used in associated synthesis techniques. Here, we report on a two-step method to graft polyvinylpyrrolidone (PVP), and a one-step method for octadecylphosphonic acid (OPA), onto the outer surfaces of imogolite nanotubes. The goal of these approaches was to improve and maintain nanotube dispersion in polymer compatible polar and non-polar solvents. The PVP coating modified the imogolite surface charge from positive to weakly negative at pH ≤ 9; the OPA made it weakly positive at acidic pH values to negative at pH ≥ 7. The PVP surface coating stabilized the nanotubes through steric hindrance in polar protic, dipolar aprotic, and chloroform. In difference to the PVP, the OPA surface coating allowed the nanotubes to be dispersed in n-hexane and chloroform, but not in the polar solvents. The lack of miscibility in the polar solvents, as well as the better dispersion in n-hexane, was attributed to the stronger hydrophobicity of the OPA polymer relative to the PVP. [Figure not available: see fulltext.

  13. Political Competition and Polarization

    DEFF Research Database (Denmark)

    Schultz, Christian

    This paper considers political competition and the consequences of political polarization when parties are better informed about how the economy functions than voters are. Specifically, parties know the cost producing a public good, voters do not. An incumbent's choice of policy acts like a signa...... for costs before an upcoming election. It is shown that the more polarized the political parties the more distorted the incumbent's policy choice.......This paper considers political competition and the consequences of political polarization when parties are better informed about how the economy functions than voters are. Specifically, parties know the cost producing a public good, voters do not. An incumbent's choice of policy acts like a signal...

  14. Physics of polarized targets

    CERN Document Server

    Niinikoski, Tapio

    2014-01-01

    For developing, building and operating solid polarized targets we need to understand several fields of physics that have seen sub stantial advances during the last 50 years. W e shall briefly review a selection of those that are important today. These are: 1) quantum statistical methods to describe saturation and relaxation in magnetic resonance; 2) equal spin temperature model for dy namic nuclear polarization; 3 ) weak saturation during NMR polarization measurement; 4 ) refrigeration using the quantum fluid properties of helium isotopes. These, combined with superconducting magnet technologies, permit today to reach nearly complete pola rization of almost any nuclear spins. Targets can be operated in frozen spin mode in rather low and inhomogeneous field of any orientation, and in DNP mode in beams of high intensity. Beyond such experiments of nuclear and particle physics, applications a re also emerging in macromolecular chemistry and in magnetic resonance imaging. This talk is a tribute to Michel Borghini...

  15. No More Polarization, Please!

    DEFF Research Database (Denmark)

    Hansen, Mia Reinholt

    The organizational science literature on motivation has for long been polarized into two main positions; the organizational economic position focusing on extrinsic motivation and the organizational behavior position emphasizing intrinsic motivation. With the rise of the knowledge economy...... and the increasing levels of complexities it entails, such polarization is not fruitful in the attempt to explain motivation of organizational members. This paper claims that a more nuanced perspective on motivation, acknowledging the co-existence of intrinsic and extrinsic motivation, the possible interaction...... between the two as well as different types of motivations filling in the gap between the two polar types, is urgently needed in the organizational science literature. By drawing on the research on intrinsic and extrinsic motivation conducted in social psychology and combining this with contributions from...

  16. Polarized source upgrading

    International Nuclear Information System (INIS)

    Clegg, T.B.; Rummel, R.L.; Carter, E.P.; Westerfeldt, C.R.; Lovette, A.W.; Edwards, S.E.

    1985-01-01

    The decision was made this past year to move the Lamb-shift polarized ion source which was first installed in the laboratory in 1970. The motivation was the need to improve the flexibility of spin-axis orientation by installing the ion source with a new Wien-filter spin precessor which is capable of rotating physically about the beam axis. The move of the polarized source was accomplished in approximately two months, with the accelerator being turned off for experiments during approximately four weeks of this time. The occasion of the move provided the opportunity to rewire completely the entire polarized ion source frame and to rebuild approximately half of the electronic chassis on the source. The result is an ion source which is now logically wired and carefully documented. Beams obtained from the source are much more stable than those previously available

  17. A lunar polar expedition

    Science.gov (United States)

    Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

    1992-09-01

    Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

  18. POLARIZED NEUTRONS IN RHIC

    Energy Technology Data Exchange (ETDEWEB)

    COURANT,E.D.

    1998-04-27

    There does not appear to be any obvious way to accelerate neutrons, polarized or otherwise, to high energies by themselves. To investigate the behavior of polarized neutrons the authors therefore have to obtain them by accelerating them as components of heavier nuclei, and then sorting out the contribution of the neutrons in the analysis of the reactions produced by the heavy ion beams. The best neutron carriers for this purpose are probably {sup 3}He nuclei and deuterons. A polarized deuteron is primarily a combination of a proton and a neutron with their spins pointing in the same direction; in the {sup 3}He nucleus the spins of the two protons are opposite and the net spin (and magnetic moment) is almost the same as that of a free neutron. Polarized ions other than protons may be accelerated, stored and collided in a ring such as RHIC provided the techniques proposed for polarized proton operation can be adapted (or replaced by other strategies) for these ions. To accelerate polarized particles in a ring, one must make provisions for overcoming the depolarizing resonances that occur at certain energies. These resonances arise when the spin tune (ratio of spin precession frequency to orbit frequency) resonates with a component present in the horizontal field. The horizontal field oscillates with the vertical motion of the particles (due to vertical focusing); its frequency spectrum is dominated by the vertical oscillation frequency and its modulation by the periodic structure of the accelerator ring. In addition, the magnet imperfections that distort the closed orbit vertically contain all integral Fourier harmonics of the orbit frequency.

  19. Dark Polar Dunes

    Science.gov (United States)

    2005-01-01

    20 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, acquired during northern summer in December 2004, shows dark, windblown sand dunes in the north polar region of Mars. A vast sea of sand dunes nearly surrounds the north polar cap. These landforms are located near 80.3oN, 144.1oW. Light-toned features in the image are exposures of the substrate that underlies the dune field. The image covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.

  20. Imaging with Polarized Neutrons

    Directory of Open Access Journals (Sweden)

    Nikolay Kardjilov

    2018-01-01

    Full Text Available Owing to their zero charge, neutrons are able to pass through thick layers of matter (typically several centimeters while being sensitive to magnetic fields due to their intrinsic magnetic moment. Therefore, in addition to the conventional attenuation contrast image, the magnetic field inside and around a sample can be visualized by detecting changes of polarization in a transmitted beam. The method is based on the spatially resolved measurement of the cumulative precession angles of a collimated, polarized, monochromatic neutron beam that traverses a magnetic field or sample.

  1. The polar mesosphere

    International Nuclear Information System (INIS)

    Morris, Ray; Murphy, Damian

    2008-01-01

    The mesosphere region, which lies at the edge of space, contains the coldest layer of the Earth's atmosphere, with summer temperatures as low as minus 130 °C. In this extreme environment ice aerosol layers have appeared since the dawn of industrialization—whose existence may arguably be linked to human influence—on yet another layer of the Earth's fragile atmosphere. Ground-based and space-based experiments conducted in the Arctic and Antarctic during the International Polar Year (IPY) aim to address limitations in our knowledge and to advance our understanding of thermal and dynamical processes at play in the polar mesosphere

  2. Internal polarized targets

    Energy Technology Data Exchange (ETDEWEB)

    Kinney, E.R.; Coulter, K.; Gilman, R.; Holt, R.J.; Kowalczyk, R.S.; Napolitano, J.; Potterveld, D.H.; Young, L. (Argonne National Lab., IL (USA)); Mishnev, S.I.; Nikolenko, D.M.; Popov, S.G.; Rachek, I.A.; Temnykh, A.B.; Toporkov, D.K.; Tsentalovich, E.P.; Wojtsekhowski, B.B. (AN SSSR, Novosibirsk (USSR). Inst. Yadernoj Fiziki)

    1989-01-01

    Internal polarized targets offer a number of advantages over external targets. After a brief review of the basic motivation and principles behind internal polarized targets, the technical aspects of the atomic storage cell will be discussed in particular. Sources of depolarization and the means by which their effects can be ameliorated will be described, especially depolarization by the intense magnetic fields arising from the circulating particle beam. The experience of the Argonne Novosibirsk collaboration with the use of a storage cell in a 2 GeV electron storage ring will be the focus of this technical discussion. 17 refs., 11 figs.

  3. AGS polarized H- source

    International Nuclear Information System (INIS)

    Kponou, A.; Alessi, J.G.; Sluyters, T.

    1985-01-01

    The AGS polarized H - source is now operational. During a month-long experimental physics run in July 1984, pulses equivalent to 15 μA x 300 μs (approx. 3 x 10 10 protons) were injected into the RFQ preaccelerator. Beam polarization, measured at 200 MeV, was approx. 75%. After the run, a program to increase the H - yield of the source was begun and significant progress has been made. The H - current is now frequently 20 to 30 μA. A description of the source and some details of our operating experience are given. We also briefly describe the improvement program

  4. Polarization transfer from polarized nuclear spin to μ- spin in muonic atom

    International Nuclear Information System (INIS)

    Kuno, Yoshitaka; Nagamine, Kanetada; Yamazaki, Toshimitsu.

    1987-02-01

    A theoretical study of polarization transfer from an initially-polarized nuclear spin to a μ - spin in a muonic atom is given. The switching of the hyperfine interaction at excited muonic states as well as at the ground 1s state is taken into account. The upper state of hyperfine doublet at the muonic 1s state is considered to proceed down to the lower state. It is found that as the hyperfine interaction becomes effective at higher excited muonic orbitals, a less extent of polarization is transferred from the nuclear spin to the μ - spin. The theoretical values obtained are compared with the recent experiment of μ - repolarization in a polarized 209 Bi target. (author)

  5. Effect of light source parameters on the polarization properties of the beam

    Science.gov (United States)

    Liu, Dan; Liu, Yan; Jiang, Hui-lin; Liu, Zhi; Zhou, Xin; Fang, Hanhan

    2013-08-01

    Polarized laser has been widely used in free space optical communication, laser radar, and laser ranging system because of its advantages of good performance in recent years. The changes of laser polarization properties in the process of transmission in atmospheric turbulence have a certain impact on the system performance. The paper research on the rule of polarization properties changes of Gauss Schell model beam in turbulent conditions. And analysis the main factors to affect the polarization properties by numerical simulation using MATLAB software tools. The factors mainly including: initial polarization, coherence coefficient, spot size and the intensity of the atmospheric turbulent. The simulation results show that, the degree of polarization will converge to the initial polarization when the beam propagation in turbulent conditions. The degrees of polarization change to different value when initial polarization of beam is different in a short distance. And, the degrees of polarization converge to the initial polarization after long distance. Beam coherence coefficient bigger, the degree of polarization and change range increases bigger. The change of polarization more slowly for spot size is bigger. The change of polarization change is faster for longer wavelength. The conclusion of the study indicated that the light source parameters effect the changes of polarization properties under turbulent conditions. The research provides theory basis for the polarization properties of the laser propagation, and it will plays a significant role in optical communication and target recognition.

  6. The physics of polarization

    Science.gov (United States)

    Landi Degl'Innocenti, Egidio

    This course is intended to give a description of the basic physical concepts which underlie the study and the interpretation of polarization phenomena. Apart from a brief historical introduction (Sect. 1), the course is organized in three parts. A first part (Sects. 2 - 6) covers the most relevant facts about the polarization phenomena that are typically encountered in laboratory applications and in everyday life. In Sect. 2, the modern description of polarization in terms of the Stokes parameters is recalled, whereas Sect. 3 is devoted to introduce the basic tools of laboratory polarimetry, such as the Jones calculus and the Mueller matrices. The polarization phenomena which are met in the reflection and refraction of a beam of radiation at the separation surface between two dielectrics, or between a dielectric and a metal, are recalled in Sect. 4. Finally, Sect. 5 gives an introduction to the phenomena of dichroism and of anomalous dispersion and Sect. 6 summarizes the polarization phenomena that are commonly encountered in everyday life. The second part of this course (Sects. 7-14) deals with the description, within the formalism of classical physics, of the spectro-polarimetric properties of the radiation emitted by accelerated charges. Such properties are derived by taking as starting point the Liénard and Wiechert equations that are recalled and discussed in Sect. 7 both in the general case and in the non-relativistic approximation. The results are developed to find the percentage polarization, the radiation diagram, the cross-section and the spectral characteristics of the radiation emitted in different phenomena particularly relevant from the astrophysical point of view. The emission of a linear antenna is derived in Sect. 8. The other Sections are devoted to Thomson scattering (Sect. 9), Rayleigh scattering (Sect. 10), Mie scattering (Sect. 11), bremsstrahlung radiation (Sect. 12), cyclotron radiation (Sect. 13), and synchrotron radiation (Sect. 14

  7. Polarized Proton Collisions at RHIC

    CERN Document Server

    Bai, Mei; Alekseev, Igor G; Alessi, James; Beebe-Wang, Joanne; Blaskiewicz, Michael; Bravar, Alessandro; Brennan, Joseph M; Bruno, Donald; Bunce, Gerry; Butler, John J; Cameron, Peter; Connolly, Roger; De Long, Joseph; Drees, Angelika; Fischer, Wolfram; Ganetis, George; Gardner, Chris J; Glenn, Joseph; Hayes, Thomas; Hseuh Hsiao Chaun; Huang, Haixin; Ingrassia, Peter; Iriso, Ubaldo; Laster, Jonathan S; Lee, Roger C; Luccio, Alfredo U; Luo, Yun; MacKay, William W; Makdisi, Yousef; Marr, Gregory J; Marusic, Al; McIntyre, Gary; Michnoff, Robert; Montag, Christoph; Morris, John; Nicoletti, Tony; Oddo, Peter; Oerter, Brian; Osamu, Jinnouchi; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Roser, Thomas; Satogata, Todd; Smith, Kevin T; Svirida, Dima; Tepikian, Steven; Tomas, Rogelio; Trbojevic, Dejan; Tsoupas, Nicholaos; Tuozzolo, Joseph; Vetter, Kurt; Wilinski, Michelle; Zaltsman, Alex; Zelenski, Anatoli; Zeno, Keith; Zhang, S Y

    2005-01-01

    The Relativistic Heavy Ion Collider~(RHIC) provides not only collisions of ions but also collisions of polarized protons. In a circular accelerator, the polarization of polarized proton beam can be partially or fully lost when a spin depolarizing resonance is encountered. To preserve the beam polarization during acceleration, two full Siberian snakes were employed in RHIC to avoid depolarizing resonances. In 2003, polarized proton beams were accelerated to 100~GeV and collided in RHIC. Beams were brought into collisions with longitudinal polarization at the experiments STAR and PHENIX by using spin rotators. RHIC polarized proton run experience demonstrates that optimizing polarization transmission efficiency and improving luminosity performance are significant challenges. Currently, the luminosity lifetime in RHIC is limited by the beam-beam effect. The current state of RHIC polarized proton program, including its dedicated physics run in 2005 and efforts to optimize luminosity production in beam-beam limite...

  8. Backscattering and negative polarization of agglomerate particles.

    Science.gov (United States)

    Zubko, Evgenij; Shkuratov, Yuriy; Hart, Matthew; Eversole, Jay; Videen, Gorden

    2003-09-01

    We used the discrete dipole approximation to study the backscattering of agglomerate particles consisting of oblong monomers. We varied the aspect ratio of the monomers from approximately 1 (sphere) to 4, while we kept the total particle volume equivalent to that of an x = 10 sphere for m = 1.59 + i0 and 1.50 + i0 and considered two values of agglomerate packing density: rho = 0.25 and rho = 0.1. We found that these particles do not display a prominent brightness opposition effect but do produce significant negative polarization over a range of near-backscattering angles. Increasing the monomers' aspect ratio can make the negative polarization much more prominent. We have noted also that decreasing m and p can reduce the amplitude of the negative polarization for these particles.

  9. Research progress on polar lipids of deinococcus radiodurans

    International Nuclear Information System (INIS)

    Feng Qiong; Tian Bing; Hua Yuejin

    2013-01-01

    Deinococcus radiodurans is extremely resistant to radiation, desiccation, oxidizing agents and other extreme conditions. One of the unique lipids in Deinococcus radiodurans is the polar lipid phosphoglycolipid with alkylamine as the main component. Alkylamine derived from fatty acids. The composition characteristic of lipids is one of the classification criterias of Deinococcus. This article provided an overview of the main features of the Deinococcus radiodurans and introduced special polar lipids that have been found as well as the taxonomy significances of such lipids. The research progress of the relationship between lipids and their resistance mechanisms and the prospects of special lipids in Deinococcus radidurans have also been discussed. (authors)

  10. Lobbying and political polarization

    OpenAIRE

    Ursprung, Heinrich W.

    2002-01-01

    Standard spatial models of political competition give rise to equilibria in which the competing political parties or candidates converge to a common position. In this paper I show how political polarization can be generated in models that focus on the nexus between pre-election interest group lobbying and electoral competition.

  11. Fluorescence confocal polarizing microscopy

    Indian Academy of Sciences (India)

    Much of the modern understanding of orientational order in liquid crystals (LCs) is based on polarizing microscopy (PM). A PM image bears only two-dimensional (2D) information, integrating the 3D pattern of optical birefringence over the path of light. Recently, we proposed a technique to image 3D director patterns by ...

  12. Polarization of Bremsstrahlung

    International Nuclear Information System (INIS)

    Miller, J.

    1957-01-01

    The numerical results for the polarization of Bremsstrahlung are presented. The multiple scattering of electrons in the target is taken into account. The angular-and photon energy dependences are seen on the curves for an incident 25 MeV electron energy. (Author) [fr

  13. DESY: HERA polarization

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The new HERA electron-proton collider at DESY in Hamburg achieved the first luminosity for electron-proton collisions on 19 October last year. Only one month later, on 20 November, HERA passed another important milestone with the observation of transverse electron polarization

  14. Titan Polar Landscape Evolution

    Science.gov (United States)

    Moore, Jeffrey M.

    2016-01-01

    With the ongoing Cassini-era observations and studies of Titan it is clear that the intensity and distribution of surface processes (particularly fluvial erosion by methane and Aeolian transport) has changed through time. Currently however, alternate hypotheses substantially differ among specific scenarios with respect to the effects of atmospheric evolution, seasonal changes, and endogenic processes. We have studied the evolution of Titan's polar region through a combination of analysis of imaging, elevation data, and geomorphic mapping, spatially explicit simulations of landform evolution, and quantitative comparison of the simulated landscapes with corresponding Titan morphology. We have quantitatively evaluated alternate scenarios for the landform evolution of Titan's polar terrain. The investigations have been guided by recent geomorphic mapping and topographic characterization of the polar regions that are used to frame hypotheses of process interactions, which have been evaluated using simulation modeling. Topographic information about Titan's polar region is be based on SAR-Topography and altimetry archived on PDS, SAR-based stereo radar-grammetry, radar-sounding lake depth measurements, and superposition relationships between geomorphologic map units, which we will use to create a generalized topographic map.

  15. Graphics of polar figure

    International Nuclear Information System (INIS)

    Macias B, L.R.

    1991-11-01

    The objective of this work, is that starting from a data file coming from a spectra that has been softened, and of the one that have been generated its coordinates to project it in stereographic form, to create the corresponding polar figure making use of the Cyber computer of the ININ by means of the GRAPHOS package. This work only requires a Beta, Fi and Intensity (I) enter data file. It starts of the existence of a softened spectra of which have been generated already with these data, making use of some language that in this case was FORTRAN for the Cyber computer, a program is generated supported in the Graphos package that allows starting of a reading of the Beta, Fi, I file, to generate the points in a stereographic projection and that it culminates with the graph of the corresponding polar figure. The program will request the pertinent information that is wanted to capture in the polar figure just as: date, name of the enter file, indexes of the polar figure, number of levels, radio of the stereographic projection (cms.), crystalline system to which belongs the sample, name the neuter graph file by create and to add the own general data. (Author)

  16. Genetic variance and breeding values for resistance to a wind-borne disease [Sphaerotheca macularis (Wallr. ex Fr.)] in strawberry (Fragaria x ananassa Duch.) estimated by exploring mixed and spatial models and pedigree information.

    Science.gov (United States)

    Davik, Jahn; Honne, Bjørn Ivar

    2005-07-01

    A mixed model approach was used to estimate variance components and heritabilities for resistance to powdery mildew, a wind-borne disease in strawberry. In order to improve precision in the statistical computations, spatial error control effects were included to account for systematic environmental variations in the large field trials. Pedigree information was included where feasible. Seedling families obtained from an incomplete 63-by-63 diallel cross were grown at six locations and scored subjectively for mildew attack three times during the growing season. The 63 parents included both European and American cultivars as well as advanced selections from various breeding programmes. A total of 298 full-sib families were realized, including 26 reciprocal families. No reciprocal differences were found. On a plot-mean basis, the broad-sense heritability was found to be intermediate, H(2) = 0.44-0.50, depending on whether the pedigree information was included in the model or not. The increase was mainly due to a substantial increase in the additive variance component. Likewise, the narrow-sense heritability increased from h(2) = 0.39 to h(2) = 0.45 when the pedigree information was included, while the ratio of the specific combining ability variance to the general combining ability variance fell from 13% to 10%. The predicted breeding values of the 63 parents demonstrate that important cultivars such as Elsanta and Korona are unlikely to produce progenies with a high degree of resistance. On the other hand, the Norwegian cultivar Solprins, the Canadian cultivar Kent and the Italian cultivar Patty appeared to give highly resistant progeny. At the full-sib level, the estimated disease scores ranged from 1.15 (Kent x Induka) to 4.19 (Cavendish x Avanta), revealing a huge range of variation for powdery mildew resistance available for selection.

  17. Tolerance of polar phytoplankton communities to metals

    International Nuclear Information System (INIS)

    Echeveste, P.; Tovar-Sánchez, A.; Agustí, S.

    2014-01-01

    Large amounts of pollutants reach polar regions, particularly the Arctic, impacting their communities. In this study we analyzed the toxic levels of Hg, Cd and Pb to natural phytoplankton communities of the Arctic and Southern Oceans, and compared their sensitivities with those observed on phytoplankton natural communities from temperate areas. Mercury was the most toxic metal for both Arctic and Antarctic communities, while both Cd and Pb were toxic only for the Antarctic phytoplankton. Total cell abundance of the populations forming the Arctic community increased under high Cd and Pb concentrations, probably due to a decrease of the grazing pressure or the increase of the most resistant species, although analysis of individual cells indicated that cell death was already induced at the highest levels. These results suggest that phytoplankton may have acquired adapting mechanisms to face high levels of Pb and Cd in the Arctic Ocean. Highlights: • First study analyzing the toxicity of Hg, Cd or Pb to natural polar phytoplankton. • Arctic Ocean communities highly resistant to Cd and Pb, but not to Hg. • Southern Ocean communities sensitive to Cd, Pb and Hg. • Both communities incorporated Pb at a similar level. • Arctic phytoplankton may have acquired adapting mechanisms against Cd and Pb. -- Polar phytoplankton communities are tolerant to Cd and Pb, specially the Arctic ones, suggesting the acquisition of adapting mechanisms to face metals' toxicity

  18. Polarization-Insensitive Surface Plasmon Polarization Electro-Absorption Modulator Based on Epsilon-Near-Zero Indium Tin Oxide.

    Science.gov (United States)

    Jin, Lin; Wen, Long; Liang, Li; Chen, Qin; Sun, Yunfei

    2018-02-03

    CMOS-compatible plasmonic modulators operating at the telecom wavelength are significant for a variety of on-chip applications. Relying on the manipulation of the transverse magnetic (TM) mode excited on the metal-dielectric interface, most of the previous demonstrations are designed to response only for specific polarization state. In this case, it will lead to a high polarization dependent loss, when the polarization-sensitive modulator integrates to a fiber with random polarization state. Herein, we propose a plasmonic modulator utilizing a metal-oxide indium tin oxide (ITO) wrapped around the silicon waveguide and investigate its optical modulation ability for both the vertical and horizontal polarized guiding light by tuning electro-absorption of ITO with the field-induced carrier injection. The electrically biased modulator with electron accumulated at the ITO/oxide interface allows for epsilon-near-zero (ENZ) mode to be excited at the top or lateral portion of the interface depending on the polarization state of the guiding light. Because of the high localized feature of ENZ mode, efficient electro-absorption can be achieved under the "OFF" state of the device, thus leading to large extinction ratio (ER) for both polarizations in our proposed modulator. Further, the polarization-insensitive modulation is realized by properly tailoring the thickness of oxide in two different stacking directions and therefore matching the ER values for device operating at vertical and horizontal polarized modes. For the optimized geometry configuration, the difference between the ER values of two polarization modes, i.e., the ΔER, as small as 0.01 dB/μm is demonstrated and, simultaneously with coupling efficiency above 74%, is obtained for both polarizations at a wavelength of 1.55 μm. The proposed plasmonic-combined modulator has a potential application in guiding and processing of light from a fiber with a random polarization state.

  19. Polarization-Insensitive Surface Plasmon Polarization Electro-Absorption Modulator Based on Epsilon-Near-Zero Indium Tin Oxide

    Science.gov (United States)

    Jin, Lin; Wen, Long; Liang, Li; Chen, Qin; Sun, Yunfei

    2018-02-01

    CMOS-compatible plasmonic modulators operating at the telecom wavelength are significant for a variety of on-chip applications. Relying on the manipulation of the transverse magnetic (TM) mode excited on the metal-dielectric interface, most of the previous demonstrations are designed to response only for specific polarization state. In this case, it will lead to a high polarization dependent loss, when the polarization-sensitive modulator integrates to a fiber with random polarization state. Herein, we propose a plasmonic modulator utilizing a metal-oxide indium tin oxide (ITO) wrapped around the silicon waveguide and investigate its optical modulation ability for both the vertical and horizontal polarized guiding light by tuning electro-absorption of ITO with the field-induced carrier injection. The electrically biased modulator with electron accumulated at the ITO/oxide interface allows for epsilon-near-zero (ENZ) mode to be excited at the top or lateral portion of the interface depending on the polarization state of the guiding light. Because of the high localized feature of ENZ mode, efficient electro-absorption can be achieved under the "OFF" state of the device, thus leading to large extinction ratio (ER) for both polarizations in our proposed modulator. Further, the polarization-insensitive modulation is realized by properly tailoring the thickness of oxide in two different stacking directions and therefore matching the ER values for device operating at vertical and horizontal polarized modes. For the optimized geometry configuration, the difference between the ER values of two polarization modes, i.e., the ΔER, as small as 0.01 dB/μm is demonstrated and, simultaneously with coupling efficiency above 74%, is obtained for both polarizations at a wavelength of 1.55 μm. The proposed plasmonic-combined modulator has a potential application in guiding and processing of light from a fiber with a random polarization state.

  20. Laser detection of spin-polarized hydrogen from HCl and HBr photodissociation: comparison of H- and halogen-atom polarizations.

    Science.gov (United States)

    Sofikitis, Dimitris; Rubio-Lago, Luis; Bougas, Lykourgos; Alexander, Andrew J; Rakitzis, T Peter

    2008-10-14

    Thermal HCl and HBr molecules were photodissociated using circularly polarized 193 nm light, and the speed-dependent spin polarization of the H-atom photofragments was measured using polarized fluorescence at 121.6 nm. Both polarization components, described by the a(0)(1)(perpendicular) and Re[a(1)(1)(parallel, perpendicular)] parameters which arise from incoherent and coherent dissociation mechanisms, are measured. The values of the a(0)(1)(perpendicular) parameter, for both HCl and HBr photodissociation, are within experimental error of the predictions of both ab initio calculations and of previous measurements of the polarization of the halide cofragments. The experimental and ab initio theoretical values of the Re[a(1)(1)(parallel, perpendicular)] parameter show some disagreement, suggesting that further theoretical investigations are required. Overall, good agreement occurs despite the fact that the current experiments photodissociate molecules at 295 K, whereas previous measurements were conducted at rotational temperatures of about 15 K.

  1. Polarized Raman microspectroscopy on intact human hair.

    Science.gov (United States)

    Ackermann, Katrin R; Koster, Joachim; Schlücker, Sebastian

    2008-10-01

    Polarization-resolved Raman microspectroscopy with near-infrared laser excitation was applied to intact human hair in order to non-invasively investigate the conformation and orientation of the polypeptide chains. By varying the orientation of the hair shaft relative to the polarization directions of the laser/analyzer, a set of four polarized Raman spectra is obtained; this allows to simultaneously determine both the secondary structure of hair proteins and the orientation of the polypeptide strands relative to the axis of the hair shaft. For the amide I band, results from a quantitative analysis of the polarized Raman spectra are compared with theoretically expected values for fibers with uniaxial symmetry. Based on the polarization behavior of the amide I band and further vibrational bands, a partial ordering of alpha-helical polypeptide strands parallel to the hair shaft can be concluded. We suggest that this microspectroscopic approach may be used for human hair diagnostics by detecting structural or orientational alterations of keratins.

  2. Study on the thermal structure of the Venusian polar atmosphere

    Science.gov (United States)

    Takamura, M.; Taguchi, M.; Fukuhara, T.; Kouyama, T.; Imamura, T.; Sato, T. M.; Futaguchi, M.; Yamada, T.; Nakamura, M.; Iwagami, N.; Suzuki, M.; Ueno, M.; Sato, M.; Hashimoto, G. L.; Takagi, S.

    2017-12-01

    The Venus atmosphere exhibits characteristic thermal features called `polar dipoles' and `polar collars' in both polar regions. The polar dipole which locates around the center of the polar region is warmer than mid-latitudes and the polar collar surrounding the polar dipole is colder than the other regions at the same altitude. These features were revealed by infrared observations of Venus by the previous missions. The previous observations showed that shapes of the polar dipoles can be characterized by three patterns which are the zonal wave numbers of 0-2, and that they change with time. The rotation periods of polar dipoles were determined to be 2.5 and 2.8-3.2 Earth days for the southern and northern polar regions, respectively. It has not been clear that the difference and variability in the rotation period is due to just a temporal variation, influence of solar activity, or other reasons. Sato et al. compared the appearances of both polar hot regions by a ground-based observation, rotation of the hot regions is synchronized between the northern and southern hemispheres. However, rotation periods of the northern and southern polar dipoles have not yet been directly compared. The Japanese Venus orbiter Akatsuki is a planetary meteorological satellite aiming at understanding the atmosphere dynamics of Venus. The Longwave Infrared Camera (LIR), observes thermal emission from the cloud top ( 65km). Akatsuki is in an equatorial orbit, which is suitable for simultaneous observations of both northern and southern polar regions. Rotation periods of polar vortices were derived using the LIR data by tracking a zonal position of maximum temperature. The rotation periods of polar vortices of southern and northern hemispheres are determined to be 3.0 - 8.2 and 1.6 - 5.5 Earth days, respectively (Fig.1). These rotation periods of southern polar vortex are longer than the values observed in the past. As a next step, we will derive rotation periods of the polar vortices for

  3. Characteristics of volume polarization holography with linear polarization light

    Science.gov (United States)

    Zang, Jinliang; Wu, An'an; Liu, Ying; Wang, Jue; Lin, Xiao; Tan, Xiaodi; Shimura, Tsutomu; Kuroda, Kazuo

    2015-10-01

    Volume polarization holographic recording in phenanthrenequinone-doped poly(methyl methacrylate) (PQ-PMMA) photopolymer with linear polarized light is obtained. The characteristics of the volume polarization hologram are experimentally investigated. It is found that beyond the paraxial approximation the polarization states of the holographic reconstruction light are generally different from the signal light. Based on vector wave theoretical analyses and material properties, the special exposure condition for correctly holographic reconstruction is obtained and experimentally demonstrated.

  4. Experiments with Fermilab polarized proton and polarized antiproton beams

    International Nuclear Information System (INIS)

    Yokosawa, A.

    1990-01-01

    We summarize activities concerning the Fermilab polarized beams. They include a brief description of the polarized-beam facility, measurements of beam polarization by polarimeters, asymmetry measurements in the π degree production at high p perpendicular and in the Λ (Σ degree), π ± , π degree production at large x F , and Δσ L (pp, bar pp) measurements. 18 refs

  5. NUCLEON POLARIZATION IN 3-BODY MODELS OF POLARIZED LI-6

    NARCIS (Netherlands)

    SCHELLINGERHOUT, NW; KOK, LP; COON, SA; ADAM, RM

    1993-01-01

    Just as He-3 --> can be approximately characterized as a polarized neutron target, polarized Li-6D has been advocated as a good isoscalar nuclear target for the extraction of the polarized gluon content of the nucleon. The original argument rests upon a presumed ''alpha + deuteron'' picture of Li-6,

  6. Universal spin-polarization fluctuations in one-dimensional wires with magnetic impurities

    DEFF Research Database (Denmark)

    Mortensen, Asger; Egues, J.C.

    2002-01-01

    -flip suppresses conductance fluctuations while enhancing spin-polarization fluctuations. More importantly, spin-polarization fluctuations attain a universal value 1/3 for large enough spin-flip strengths. This intrinsic spin-polarization fluctuation may pose a severe limiting factor to the realization of steady...

  7. Polarized electron beams at SLAC

    International Nuclear Information System (INIS)

    Moffeit, K.C.

    1992-11-01

    SLAC has successfully accelerated high energy polarized electrons for the Stanford Linear Collider and fixed polarized nuclear target experiments. The polarized electron beams at SLAC use a gallium arsenide (GaAlAs for E-142) photon emission source to provide the beam of polarized electrons with polarization of approximately 28% (41% for E-142). While the beam emittance is reduced in the damping ring for SLC operation a system of bend magnets and superconducting solenoids preserve and orient the spin direction for maximum longitudinal polarization at the collision point. The electron polarization is monitored with a Compton scattering polarimeter, and was typically 22% at the e+e- collision point for the 1992 run. Improvements are discussed to increase the source polarization and to reduce the depolarization effects between the source and the collision point

  8. Analytical polarization calculations beyond SLIM

    International Nuclear Information System (INIS)

    Barber, D.P.

    1989-01-01

    A comparison is made between the theories of Bell and Leinaas and of Derbenev and Kondratenko for the spin polarization in electron storage rings. A calculation of polarization in HERA using the program SMILE of Mane is presented

  9. Polarized particle levitation in hexapole field

    International Nuclear Information System (INIS)

    Jones, T.B.; Kallio, G.A.; Robinson, K.S.

    1976-06-01

    Proposed here is a novel electrostatic levitation scheme which uses the force exerted by a non-uniform electric field on a polarized particle. The scheme differs from conventional quadrupole levitation devices principally in that the levitated particle is uncharged. In order to provide the proper force required to achieve dynamic stabilization, a very intense non-uniform time-varying electric field produced by a three-dimensional hexapole electrode structure is utilized. The primary advantage of this levitation scheme might accrue in target fabrication operations where particle charge is undesirable or where reproducible charging of the particles themselves is difficult, due to high resistivity. The disadvantages of this scheme, as compared to charged particle levitation, are (i) a more complex electrode structure and (ii) significantly higher voltages. The scheme has possible application to molecular mass spectrometry, in situations where un-ionized but strongly polar or polarizable molecules are to be trapped or confined for analysis

  10. Carbon ions of different linear energy transfer (LET) values induce apoptosis & G2 cell cycle arrest in radio-resistant melanoma cells.

    Science.gov (United States)

    Jelena, Žakula; Lela, Korićanac; Otilija, Keta; Danijela, Todorović; Cirrone Giuseppe, A P; Francesco, Romano; Giacomo, Cuttone; Ivan, Petrović; Aleksandra, Ristić-Fira

    2016-05-01

    The main goal when treating malignancies with radiation is to deprive tumour cells of their reproductive potential. One approach is to induce tumour cell apoptosis. This study was conducted to evaluate the ability of carbon ions ( [12] C) to induce apoptosis and cell cycle arrest in human HTB140 melanoma cells. In this in vitro study, human melanoma HTB140 cells were irradiated with the 62 MeV/n carbon ( [12] C) ion beam, having two different linear energy transfer (LET) values: 197 and 382 keV/μm. The dose range was 2 to 16 Gy. Cell viability was estimated by the sulforhodamine B assay seven days after irradiation. The cell cycle and apoptosis were evaluated 48 h after irradiation using flow cytometry. At the same time point, protein and gene expression of apoptotic regulators were estimated using the Western blot and q-PCR methods, respectively. Cell viability experiments indicated strong anti-tumour effects of [12] C ions. The analysis of cell cycle showed that [12] C ions blocked HTB140 cells in G2 phase and induced the dose dependent increase of apoptosis. The maximum value of 21.8 per cent was attained after irradiation with LET of 197 keV/μm at the dose level of 16 Gy. Pro-apoptotic effects of [12] C ions were confirmed by changes of key apoptotic molecules: the p53, Bax, Bcl-2, poly ADP ribose polymerase (PARP) as well as nuclear factor kappa B (NFκB). At the level of protein expression, the results indicated significant increases of p53, NFκB and Bax/Bcl-2 ratio and PARP cleavage. The Bax/Bcl-2 mRNA ratio was also increased, while no change was detected in the level of NFκB mRNA. The present results indicated that anti-tumour effects of [12] C ions in human melanoma HTB140 cells were accomplished through induction of the mitochondrial apoptotic pathway as well as G2 arrest.

  11. On Determinants of Political Polarization

    OpenAIRE

    Grechyna, Daryna

    2015-01-01

    Political polarization has been shown to significantly influence a country's economic performance. However, little is known about the drivers of political polarization. In this article, we aim to identify the main determinants of political polarization using Bayesian Model Averaging to overcome the problem of model uncertainty. We find that the level of trust within a country and the degree of income inequality are the most robust determinants of political polarization.

  12. Spin-Polarization in Quasi-Magnetic Tunnel Junctions

    Science.gov (United States)

    Xie, Zheng-Wei; Li, Ling

    2017-05-01

    Spin polarization in ferromagnetic metal/insulator/spin-filter barrier/nonmagnetic metal, referred to as quasi-magnetic tunnel junctions, is studied within the free-electron model. Our results show that large positive or negative spin-polarization can be obtained at high bias in quasi-magnetic tunnel junctions, and within large bias variation regions, the degree of spin-polarization can be linearly tuned by bias. These linear variation regions of spin-polarization with bias are influenced by the barrier thicknesses, barrier heights and molecular fields in the spin-filter (SF) layer. Among them, the variations of thickness and heights of the insulating and SF barrier layers have influence on the value of spin-polarization and the linear variation regions of spin-polarization with bias. However, the variations of molecular field in the SF layer only have influence on the values of the spin-polarization and the influences on the linear variation regions of spin-polarization with bias are slight. Supported by the Key Natural Science Fund of Sichuan Province Education Department under Grant Nos 13ZA0149 and 16ZA0047, and the Construction Plan for Scientific Research Innovation Team of Universities in Sichuan Province under Grant No 12TD008.

  13. The impacts of surface polarity on the solubility of nanoparticle

    International Nuclear Information System (INIS)

    Zhu, Jianzhuo; Su, Jiguo; Ou, Xinwen; Li, Jingyuan

    2016-01-01

    In order to study the dependence of water solubility and hydration behavior of nanoparticles on their surface polarity, we designed polar nanoparticles with varying surface polarity by assigning atomic partial charge to the surface of C60. The water solubility of the nanoparticle is enhanced by several orders of magnitude after the introduction of surface polarity. Nevertheless, when the atomic partial charge grows beyond a certain value (q M ), the solubility continuously decreases to the level of nonpolar nanoparticle. It should be noted that such q M is comparable with atomic partial charge of a variety of functional groups. The hydration behaviors of nanoparticles were then studied to investigate the non-monotonic dependence of solubility on the surface polarity. The interaction between the polar nanoparticle and the hydration water is stronger than the nonpolar counterpart, which should facilitate the dissolution of the nanoparticles. On the other hand, the surface polarity also reduces the interaction of hydration water with the other water molecules and enhances the interaction between the nanoparticles which may hinder their dispersion. Besides, the introduction of surface polarity disturbs and even rearranges the hydration structure of nonpolar nanoparticle. Interestingly, the polar nanoparticle with less ordered hydration structure tends to have higher water solubility.

  14. Measurement of deuteron beam polarization before and after acceleration

    Directory of Open Access Journals (Sweden)

    A Ramazani Moghaddam Arani

    2017-02-01

    Full Text Available Beam polarization measurement in scattering experiments with a high accuracy and the lowest possible cost is an important issue. In this regard, deuteron beam polarization was measured in the low-energy beam line easily with a relatively low cost procedure and in a very short time by Lamb Shift Polarimeter (LSP. Also, the beam polarization has been measured in high-energy beam line with BINA. In low-energy line, a polarized beam of deuterons delivered by POLIS was decelerated and focused on LSP detection system. Three resonances between 52mT and 63mT show the distribution of different spin states of polarized deuteron beam. In high-energy beam line, polarization can be measured employing BINA via the H(d,dp reaction. The asymmetry ratio, was obtained as a function of azimuthal angle, φ, for several polar scattering angles. Knowing values of the analyzing powers, the ratio has been used to extract the polarization results. The obtained results show that polarization of deuteron beam that is accelerated up to the energy of 130 MeV is almost the same before and after acceleration

  15. Polarized electrogowdy spacetimes censored

    Energy Technology Data Exchange (ETDEWEB)

    Nungesser, Ernesto, E-mail: ernesto.nungesser@aei.mpg.d [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, 14476 Potsdam (Germany)

    2010-05-01

    A sketch of the proof of strong cosmic censorship is presented for a class of solutions of the Einstein-Maxwell equations, those with polarized Gowdy symmetry. A key element of the argument is the observation that by means of a suitable choice of variables the central equations in this problem can be written in a form where they are identical to the central equations for general (i.e. non-polarized) vacuum Gowdy spacetimes. Using this it is seen that the results of Ringstroem on strong cosmic censorship in the vacuum case have implications for the Einstein-Maxwell case. Working out the geometrical meaning of these analytical results leads to the main conclusion.

  16. HST observations of the limb polarization of Titan

    Science.gov (United States)

    Bazzon, A.; Schmid, H. M.; Buenzli, E.

    2014-12-01

    Context. Titan is an excellent test case for detailed studies of the scattering polarization from thick hazy atmospheres. Accurate scattering and polarization parameters have been provided by the in situ measurements of the Cassini-Huygens landing probe. For Earth-bound observations Titan can only be observed at a backscattering situation, where the disk-integrated polarization is close to zero. However, with resolved imaging polarimetry a second order polarization signal along the entire limb of Titan can be measured. Aims: We present the first limb polarization measurements of Titan, which are compared as a test to our limb polarization models. Methods: Previously unpublished imaging polarimetry from the HST archive is presented, which resolves the disk of Titan. We determine flux-weighted averages of the limb polarization and radial limb polarization profiles, and investigate the degradation and cancelation effects in the polarization signal due to the limited spatial resolution of our observations. Taking this into account we derive corrected values for the limb polarization in Titan. The results are compared with limb polarization models, using atmosphere and haze scattering parameters from the literature. Results: In the wavelength bands between 250 nm and 2 μm a strong limb polarization of about 2 - 7% is detected with a position angle perpendicular to the limb. The fractional polarization is highest around 1 μm. As a first approximation, the polarization seems to be equally strong along the entire limb. The comparison of our data with model calculations and the literature shows that the detected polarization is compatible with expectations from previous polarimetric observations taken with Voyager 2, Pioneer 11, and the Huygens probe. Conclusions: Our results indicate that ground-based monitoring measurements of the limb-polarization of Titan could be useful for investigating local haze properties and the impact of short-term and seasonal variations of

  17. PEPPo: Using a Polarized Electron Beam to Produce Polarized Positrons

    Energy Technology Data Exchange (ETDEWEB)

    Adeyemi, Adeleke H. [Hampton Univ., Hampton, VA (United States); et al.

    2015-09-01

    Polarized positron beams have been identified as either an essential or a significant ingredient for the experimental program of both the present and next generation of lepton accelerators (JLab, Super KEK B, ILC, CLIC). An experiment demonstrating a new method for producing polarized positrons has been performed at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. The PEPPo (Polarized Electrons for Polarized Positrons) concept relies on the production of polarized e⁻/e⁺ pairs from the bremsstrahlung radiation of a longitudinally polarized electron beam interacting within a high-Z conversion target. PEPPo demonstrated the effective transfer of spin-polarization of an 8.2 MeV/c polarized (P~85%) electron beam to positrons produced in varying thickness tungsten production targets, and collected and measured in the range of 3.1 to 6.2 MeV/c. In comparison to other methods this technique reveals a new pathway for producing either high-energy or thermal polarized positron beams using a relatively low polarized electron beam energy (~10MeV) .This presentation will describe the PEPPo concept, the motivations of the experiment and high positron polarization achieved.

  18. Polarization induced doped transistor

    Science.gov (United States)

    Xing, Huili; Jena, Debdeep; Nomoto, Kazuki; Song, Bo; Zhu, Mingda; Hu, Zongyang

    2016-06-07

    A nitride-based field effect transistor (FET) comprises a compositionally graded and polarization induced doped p-layer underlying at least one gate contact and a compositionally graded and doped n-channel underlying a source contact. The n-channel is converted from the p-layer to the n-channel by ion implantation, a buffer underlies the doped p-layer and the n-channel, and a drain underlies the buffer.

  19. Polar bears, Ursus maritimus

    Science.gov (United States)

    Rode, Karyn D.; Stirling, Ian

    2017-01-01

    Polar bears are the largest of the eight species of bears found worldwide and are covered in a pigment-free fur giving them the appearance of being white. They are the most carnivorous of bear species consuming a high-fat diet, primarily of ice-associated seals and other marine mammals. They range throughout the circumpolar Arctic to the southernmost extent of seasonal pack ice.

  20. Polarized advanced fuel reactors

    International Nuclear Information System (INIS)

    Kulsrud, R.M.

    1987-07-01

    The d- 3 He reaction has the same spin dependence as the d-t reaction. It produces no neutrons, so that if the d-d reactivity could be reduced, it would lead to a neutron-lean reactor. The current understanding of the possible suppression of the d-d reactivity by spin polarization is discussed. The question as to whether a suppression is possible is still unresolved. Other advanced fuel reactions are briefly discussed. 11 refs

  1. On polarization in biomembranes

    DEFF Research Database (Denmark)

    Zecchi, Karis Amata

    close to physiological conditions, making these effects biologically relevant. In this work, we consider the case of asymmetric membranes which can display spontaneous polarization in the absence of a field. Close to the phase transition, we find that the membrane displays piezoelectric, flexoelectric...... on different geometries point in the direction of a flexoelectric mechanism behind current rectification in lipid bilayers. Finally, we suggest that our updated equivalent circuit should be included in the interpretation of elctrophysiological data....

  2. Multifrequency Behaviour of Polars

    Directory of Open Access Journals (Sweden)

    K. Reinsch

    2015-02-01

    Full Text Available Cataclysmic variables emit over a wide range of the electromagnetic spectrum. In this paper I will review observations of polars in relevant passbands obtained during the last decade and will discuss their diagnostical potential to access the physics of the main components within the binary systems. This will include a discussion of intrinsic source variability and the quest for simultaneous multi-frequency observations.

  3. Field-scale electrical geophysics over an olive oil mill waste deposition site: Evaluating the information content of resistivity versus induced polarization (IP) images for delineating the spatial extent of organic contamination

    Science.gov (United States)

    Ntarlagiannis, Dimitrios; Robinson, Judith; Soupios, Pantelis; Slater, Lee

    2016-12-01

    We performed 2D resistivity and IP measurements over a known olive oil mill waste plume at a site in western Crete, Greece. The objectives of the survey were: (1) to determine whether IP is more diagnostic in delineating the spatial extent of the plume relative to resistivity measurements alone; (2) to evaluate whether the additional information content obtained from IP is worth the effort given longer data acquisition times and higher measurement errors that inevitably characterize field IP data acquisition. Complex conductivity inversion of the field IP dataset revealed that the organic plume is characterized as a region of high electrical conductivity (real part of complex conductivity) consistent with the conceptual model for the electrical structure of a biodegraded LNAPL contaminant plume. The plume is also characterized by a region of high polarizability (imaginary part of complex conductivity) that is more localized to the known plume location (based on conventional monitoring) relative to the high conductivity region in the electrical conductivity image. This observation is attributed to the fact that electrical conductivity is more strongly controlled by hydrogeological and geological characteristics of the site that mask the response from the biodegraded plume. This result encourages the use of field IP to improve the spatial delineation of organic contamination in the subsurface. However, more laborious field procedures are required to acquire reliable field IP data and the inversion of field IP data remains more challenging than resistivity data alone.

  4. Polar Business Design

    Directory of Open Access Journals (Sweden)

    Sébastien Caisse

    2014-02-01

    Full Text Available Polar business design aims to enable entrepreneurs, managers, consultants, researchers, and business students to better tackle model-based analysis, creation, and transformation of businesses, ventures, and, more generically, collective endeavors of any size and purpose. It is based on a systems-thinking approach that builds on a few interrelated core concepts to create holistic visual frameworks. These core concepts act as poles linked by meaningful dyads, flows, and faces arranged in geometric shapes. The article presents two such polar frameworks as key findings in an ongoing analytic autoethnography: the three-pole Value−Activity−Stakeholder (VAS triquetra and the four-pole Offer−Creation−Character−Stakeholder (OCCS tetrahedron. The VAS triquetra is a more aggregated model of collective endeavors. The OCCS tetrahedron makes a trade-off between a steeper learning curve and deeper, richer representation potential. This article discusses how to use these two frameworks as well as their limits, and explores the potential that polar business design offers for future research.

  5. Public Values

    DEFF Research Database (Denmark)

    Beck Jørgensen, Torben; Rutgers, Mark R.

    2015-01-01

    administration is approached in terms of processes guided or restricted by public values and as public value creating: public management and public policy-making are both concerned with establishing, following and realizing public values. To study public values a broad perspective is needed. The article suggest...

  6. Evaluation of Extraction Protocols for Simultaneous Polar and Non-Polar Yeast Metabolite Analysis Using Multivariate Projection Methods

    Directory of Open Access Journals (Sweden)

    Nicolas P. Tambellini

    2013-07-01

    Full Text Available Metabolomic and lipidomic approaches aim to measure metabolites or lipids in the cell. Metabolite extraction is a key step in obtaining useful and reliable data for successful metabolite studies. Significant efforts have been made to identify the optimal extraction protocol for various platforms and biological systems, for both polar and non-polar metabolites. Here we report an approach utilizing chemoinformatics for systematic comparison of protocols to extract both from a single sample of the model yeast organism Saccharomyces cerevisiae. Three chloroform/methanol/water partitioning based extraction protocols found in literature were evaluated for their effectiveness at reproducibly extracting both polar and non-polar metabolites. Fatty acid methyl esters and methoxyamine/trimethylsilyl derivatized aqueous compounds were analyzed by gas chromatography mass spectrometry to evaluate non-polar or polar metabolite analysis. The comparative breadth and amount of recovered metabolites was evaluated using multivariate projection methods. This approach identified an optimal protocol consisting of 64 identified polar metabolites from 105 ion hits and 12 fatty acids recovered, and will potentially attenuate the error and variation associated with combining metabolite profiles from different samples for untargeted analysis with both polar and non-polar analytes. It also confirmed the value of using multivariate projection methods to compare established extraction protocols.

  7. Resistive Threshold Logic

    OpenAIRE

    James, A. P.; Francis, L. R. V. J.; Kumar, D.

    2013-01-01

    We report a resistance based threshold logic family useful for mimicking brain like large variable logic functions in VLSI. A universal Boolean logic cell based on an analog resistive divider and threshold logic circuit is presented. The resistive divider is implemented using memristors and provides output voltage as a summation of weighted product of input voltages. The output of resistive divider is converted into a binary value by a threshold operation implemented by CMOS inverter and/or O...

  8. Deep Value

    DEFF Research Database (Denmark)

    Asness, Clifford S.; Liew, John M.; Pedersen, Lasse Heje

    We define "deep value" as episodes where the valuation spread between cheap and expensive securities is wide relative to its history. Examining deep value across global individual equities, equity index futures, currencies, and global bonds provides new evidence on competing theories for the valu....... Lastly, we find that deep value episodes tend to cluster and a deep value trading strategy generates excess returns not explained by traditional risk factors.......We define "deep value" as episodes where the valuation spread between cheap and expensive securities is wide relative to its history. Examining deep value across global individual equities, equity index futures, currencies, and global bonds provides new evidence on competing theories for the value...... premium. Following these episodes, the value strategy has (1) high average returns; (2) low market betas, but high betas to a global value factor; (3) deteriorating fundamentals; (4) negative news sentiment; (5) selling pressure; (6) increased limits to arbitrage; and (7) increased arbitrage activity...

  9. The predictive value of ERG protein expression for development of castration-resistant prostate cancer in hormone-naïve advanced prostate cancer treated with primary androgen deprivation therapy

    DEFF Research Database (Denmark)

    Berg, Kasper Drimer; Røder, Martin A; Thomsen, Frederik B

    2015-01-01

    BACKGROUND: Biomarkers predicting response to primary androgen deprivation therapy (ADT) and risk of castration-resistant prostate cancer (CRPC) is lacking. We aimed to analyse the predictive value of ERG expression for development of CRPC. METHODS: In total, 194 patients with advanced and....../or metastatic prostate cancer (PCa) treated with first-line castration-based ADT were included. ERG protein expression was analysed in diagnostic specimens using immunohistochemistry (anti-ERG, EPR3864). Time to CRPC was compared between ERG subgroups using multiple cause-specific Cox regression stratified...... on ERG-status. Risk reclassification and time-dependent area under the ROC curves were used to assess the discriminative ability of ERG-status. Time to PSA-nadir, proportion achieving PSA-nadir ≤0.2 ng/ml, and risk of PCa-specific death were secondary endpoints. RESULTS: Median follow-up was 6.8 years...

  10. Circular polarization in a non-magnetic resonant tunneling device

    Directory of Open Access Journals (Sweden)

    Airey Robert

    2011-01-01

    Full Text Available Abstract We have investigated the polarization-resolved photoluminescence (PL in an asymmetric n-type GaAs/AlAs/GaAlAs resonant tunneling diode under magnetic field parallel to the tunnel current. The quantum well (QW PL presents strong circular polarization (values up to -70% at 19 T. The optical emission from GaAs contact layers shows evidence of highly spin-polarized two-dimensional electron and hole gases which affects the spin polarization of carriers in the QW. However, the circular polarization degree in the QW also depends on various other parameters, including the g-factors of the different layers, the density of carriers along the structure, and the Zeeman and Rashba effects.

  11. Steroid hormone profile in female polar bears (Ursus maritimus)

    DEFF Research Database (Denmark)

    Gustavson, Lisa; Jenssen, Bjorn Munro; Bytingsvik, Jenny

    2015-01-01

    -4 pathway in polar bears, similar to rodents. The large individual variability in steroid levels reported here most likely reflects the differences in reproductive status of the female polar bears during mating season. The steroid data establish reference values of steroid hormones and may...... is the first study to report circulating concentrations of nine steroid hormones (i.e., estrogens, androgens and progestagens) in female polar bears (Ursus maritimus). The aim of the study was to investigate the effects of age, condition, location and reproductive status on steroid profile in female polar...... bears. Levels of pregnenolone (PRE), progesterone, androstenedione (AN), dehydroepiandrosterone (DHEA), testosterone, dihydrotestosterone, estrone (E1), 17α-estradiol (αE2) and 17β-estradiol (βE2) were quantified in blood (serum) of free-living female polar bears (n = 15) from Svalbard, Norway, by gas...

  12. Meteorite Impact "Earthquake" Features (Rock Liquefaction, Surface Wave Deformations, Seismites) from Ground Penetrating Radar (GPR) and Geoelectric Complex Resistivity/Induced Polarization (IP) Measurements, Chiemgau (Alpine Foreland, Southeast Germany)

    Science.gov (United States)

    Ernstson, K.; Poßekel, J.

    2017-12-01

    Densely spaced GPR and complex resistivity measurements on a 30,000 square meters site in a region of enigmatic sinkhole occurrences in unconsolidated Quaternary sediments have featured unexpected and highlighting results from both a meteorite impact research and an engineering geology point of view. The GPR measurements and a complex resistivity/IP electrical imaging revealed extended subrosion depressions related with a uniformly but in various degrees of intensity deformed loamy and gravelly ground down to at least 10 m depth. Two principle observations could be made from both the GPR high-resolution measurements and the more integrating resistivity and IP soundings with both petrophysical evidences in good complement. Subrosion can be shown to be the result of prominent sandy-gravelly intrusions and extrusions typical of rock liquefaction processes well known to occur during strong earthquakes. Funnel-shaped structures with diameters up to 25 m near the surface and reaching down to the floating ground water level at 10 m depth were measured. GPR radargrams could trace prominent gravelly-material transport bottom-up within the funnels. Seen in both GPR tomography and resistivity/IP sections more or less the whole investigated area is overprinted by wavy deformations of the unconsolidated sediments with wavelengths of the order of 5 - 10 m and amplitudes up to half a meter, likewise down to 10 m depth. Substantial earthquakes are not known in this region. Hence, the observed heavy underground disorder is considered the result of the prominent earthquake shattering that must have occurred during the Holocene (Bronze Age/Celtic era) Chiemgau meteorite impact event that produced a 60 km x 30 km sized crater strewn field directly hosting the investigated site. Depending on depth and size of floating aquifers local concentrations of rock liquefaction and seismic surface waves (probably LOVE waves) to produce the wavy deformations could develop, when the big

  13. QCD Analysis of Polarized Scattering Data and New Polarized Parton Distributions

    International Nuclear Information System (INIS)

    Bluemlein, J.; Boettcher, H.

    2002-01-01

    In this talk results from a new QCD analysis in Leading (LO) and Next-to-Leading (NLO) Order are presented. New parametrizations of the polarized quark and gluon densities are derived together with parametrizations of their fully correlated 1σ error bands. Furthermore the value of α s (M 2 Z ) is determined. Finally a number of low moments of the polarized parton densities are compared with results from lattice simulations. All details of the analysis are given in J. Bluemlein, H. Boettcher, Nucl. Phys. B636, 225 (2002). (author)

  14. Polarization-angle dependence of photoluminescence intensity of ordered GaInP{sub 2} layers: observation of polarization memory

    Energy Technology Data Exchange (ETDEWEB)

    Prutskij, T.; Brito-Orta, R. [Instituto de Ciencias, BUAP, Puebla (Mexico); Pelosi, C. [IMEM/CNR, Parma (Italy)

    2008-09-15

    We compare measured and calculated polarization-angle dependencies of the intensity of the photoluminescence emission from MOVPE-grown GaInP{sub 2} layers with different ordering parameters. We measured the polarization-angle dependencies of the emission propagating along the [001],[110] and [1 anti 10] directions at room temperature. Symmetry considerations were used to calculate the dependence of the relative intensity of the PL emission which was linearly polarized along different directions and to estimate the value of the valence-band splitting by fitting the measured dependencies with calculated curves. An intriguing influence of the polarization of the exciting beam on the relative amount of the polarized PL emission was observed in the emission from the (110) plane. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Circularly polarized antennas

    CERN Document Server

    Gao, Steven; Zhu, Fuguo

    2013-01-01

    This book presents a comprehensive insight into the design techniques for different types of CP antenna elements and arrays In this book, the authors address a broad range of topics on circularly polarized (CP) antennas. Firstly, it introduces to the reader basic principles, design techniques and characteristics of various types of CP antennas, such as CP patch antennas, CP helix antennas, quadrifilar helix antennas (QHA), printed quadrifilar helix antennas (PQHA), spiral antenna, CP slot antennas, CP dielectric resonator antennas, loop antennas, crossed dipoles, monopoles and CP horns. Adva

  16. Plasma polarization spectroscopy

    CERN Document Server

    Iwamae, Atsushi

    2008-01-01

    Plasma Polarization Spectroscopy (PPS) is now becoming a standard diagnostic technique for working with laboratory plasmas. This new area needs a comprehensive framework, both experimental and theoretical. This book reviews the historical development of PPS, develops a general theoretical formulation to deal with this phenomenon, along with an overview of relevant cross sections, and reports on laboratory experiments so far performed. It also includes various facets that are interesting from this standpoint, e.g. X-ray lasers and effects of microwave irradiation. It also offers a timely discussion of instrumentation that is quite important in a practical PPS experiment.

  17. Polarization of a stored electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Chao, A.W.

    1981-07-01

    Synchrotron radiation by a point charge is a familiar subject in classical electrodynamics. Perhaps less familiar are some quantum mechanical corrections to the classical results. Some of those quantum aspects of synchrotron radiation are described. One of the quantum effects leads to the expectation that electrons in a storage ring will polarize themselves to 92% - a surprisingly high value. A semi-classical derivation of the quantum effects is given. An effort has been made to minimize the need of using quantum mechanics. Results are put together to derive a final expression of beam polarization. Conditions under which the expected 92% polarization is destroyed are found and attributed to depolarization resonances. The various depolarization mechanisms are first illustrated by an idealized example and then systematically treated by a matrix formalism. It is shown that the strength of depolarization is specified by a key quantity called the spin chromaticity. Finally as an application of the obtained results, an estimate of the achievable level of beam polarization for two existing electron storage rings, SPEAR and PEP, is given.

  18. Resistance in psychotherapy with adolescents.

    Science.gov (United States)

    Graafsma, T; Anbeek, M

    1984-03-01

    Resistances are of considerable significance in psychoterapy with adolescents. In this article, that significance is investigated further, because the way in which resistances are valued is very important in treatment. The forms in which it appears and, the source and intention of resistances are discussed. It is proposed that the investigation of resistances should not be aimed primarily at their removal.

  19. DETECTING EXOMOONS AROUND SELF-LUMINOUS GIANT EXOPLANETS THROUGH POLARIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Sujan [Indian Institute of Astrophysics, Koramangala 2nd Block, Bangalore 560 034 (India); Marley, Mark S., E-mail: sujan@iiap.res.in, E-mail: Mark.S.Marley@NASA.gov [NASA Ames Research Center, MS-245-3, Moffett Field, CA 94035 (United States)

    2016-06-20

    Many of the directly imaged self-luminous gas-giant exoplanets have been found to have cloudy atmospheres. Scattering of the emergent thermal radiation from these planets by the dust grains in their atmospheres should locally give rise to significant linear polarization of the emitted radiation. However, the observable disk-averaged polarization should be zero if the planet is spherically symmetric. Rotation-induced oblateness may yield a net non-zero disk-averaged polarization if the planets have sufficiently high spin rotation velocity. On the other hand, when a large natural satellite or exomoon transits a planet with a cloudy atmosphere along the line of sight, the asymmetry induced during the transit should give rise to a net non-zero, time-resolved linear polarization signal. The peak amplitude of such time-dependent polarization may be detectable even for slowly rotating exoplanets. Therefore, we suggest that large exomoons around directly imaged self-luminous exoplanets may be detectable through time-resolved imaging polarimetry. Adopting detailed atmospheric models for several values of effective temperature and surface gravity that are appropriate for self-luminous exoplanets, we present the polarization profiles of these objects in the infrared during the transit phase and estimate the peak amplitude of polarization that occurs during the inner contacts of the transit ingress/egress phase. The peak polarization is predicted to range between 0.1% and 0.3% in the infrared.

  20. DETECTING EXOMOONS AROUND SELF-LUMINOUS GIANT EXOPLANETS THROUGH POLARIZATION.

    Science.gov (United States)

    Sengupta, Sujan; Marley, Mark S

    2016-01-01

    Many of the directly imaged self-luminous gas giant exoplanets have been found to have cloudy atmospheres. Scattering of the emergent thermal radiation from these planets by the dust grains in their atmospheres should locally give rise to significant linear polarization of the emitted radiation. However, the observable disk averaged polarization should be zero if the planet is spherically symmetric. Rotation-induced oblateness may yield a net non-zero disk averaged polarization if the planets have sufficiently high spin rotation velocity. On the other hand, when a large natural satellite or exomoon transits a planet with cloudy atmosphere along the line of sight, the asymmetry induced during the transit should give rise to a net non-zero, time resolved linear polarization signal. The peak amplitude of such time dependent polarization may be detectable even for slowly rotating exoplanets. Therefore, we suggest that large exomoons around directly imaged self-luminous exoplanets may be detectable through time resolved imaging polarimetry. Adopting detailed atmospheric models for several values of effective temperature and surface gravity which are appropriate for self-luminous exoplanets, we present the polarization profiles of these objects in the infrared during transit phase and estimate the peak amplitude of polarization that occurs during the inner contacts of the transit ingress/egress phase. The peak polarization is predicted to range between 0.1 and 0.3 % in the infrared.

  1. Optical characterization and polarization calibration for rigid endoscopes

    Science.gov (United States)

    Garcia, Missael; Gruev, Viktor

    2017-02-01

    Polarization measurements give orthogonal information to spectral images making them a great tool in the characterization of environmental parameters in nature. Thus, polarization imagery has proven to be remarkably useful in a vast range of biomedical applications. One such application is the early diagnosis of flat cancerous lesions in murine colorectal tumor models, where polarization data complements NIR fluorescence analysis. Advances in nanotechnology have led to compact and precise bio-inspired imaging sensors capable of accurately co-registering multidimensional spectral and polarization information. As more applications emerge for these imagers, the optics used in these instruments get very complex and can potentially compromise the original polarization state of the incident light. Here we present a complete optical and polarization characterization of three rigid endoscopes of size 1.9mm x 10cm (Karl Storz, Germany), 5mm x 30cm, and 10mm x 33cm (Olympus, Germany), used in colonoscopy for the prevention of colitis-associated cancer. Characterization results show that the telescope optics act as retarders and effectively depolarize the linear component. These incorrect readings can cause false-positives or false-negatives leading to an improper diagnosis. In this paper, we offer a polarization calibration scheme for these endoscopes based on Mueller calculus. By modeling the optical properties from training data as real-valued Mueller matrices, we are able to successfully reconstruct the initial polarization state acquired by the imaging system.

  2. Computing the hadronic vacuum polarization function by analytic continuation

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xu [KEK National High Energy Physics, Tsukuba (Japan); Hashimoto, Shoji [KEK National High Energy Physics, Tsukuba (Japan); The Graduate Univ. for Advanced Studies, Tsukuba (Japan). School of High Energy Accelerator Science; Hotzel, Grit [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Petschlies, Marcus [The Cyprus Institute, Nicosia (Cyprus); Renner, Dru B. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2013-07-15

    We propose a method to compute the hadronic vacuum polarization function on the lattice at continuous values of photon momenta bridging between the space-like and time-like regions. We provide two independent derivations of this method showing that it leads to the desired hadronic vacuum polarization function in Minkowski space-time. We show with the example of the leading- order QCD correction to the muon anomalous magnetic moment that this approach can provide a valuable alternative method for calculations of physical quantities where the hadronic vacuum polarization function enters.

  3. Scale dependence and small x behaviour of polarized parton distributions

    CERN Document Server

    Ball, R D; Ridolfi, G; Forte, S; Ridolfi, G

    1995-01-01

    We discuss perturbative evolution of the polarized structure function g_1 in the (x,Q^2) plane, with special regard to the small-x region. We determine g_1 in terms of polarized quark and gluon distributions using coefficient functions to order alpha_s. At small x g_1 then displays substantial scale dependence, which necessarily implies a corresponding scale dependence in the large-x region. This scale dependence has significant consequences for the extraction of the first moment from the experimental data, reducing its value while increasing the error. Conversely, the scale dependence may be used to constrain the size of the polarized gluon distribution.

  4. Radiative capture of polarized neutrons by aluminium and manganese nuclei

    International Nuclear Information System (INIS)

    1979-01-01

    This investigation treats the angular dependence of the intensity and of the circular polarization of gamma-radiation, that is emitted after capture of polarized neutrons by polarized and unpolarized targets. Interference effects between the (n,γ)-reaction amplitudes with different channel spin are discussed and angular distribution coefficients are calculated in case mixing of dipole and quadrupole radiation occurs. It is indicated how the influence of p-wave capture may be taken into account. The nuclear orientation experiments on aluminium yield the values of the angular distribution coefficients of primary and secondary gamma-ray transitions and by a chi 2 -analysis five spin values are assigned uniquely and several α-values are determined. The nuclear orientation experiments on manganese lead to α-values and unique spin assigments for thirteen nuclear states in 56 Mn. (Auth.)

  5. Polarized proton collider at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S.Y.; Luccio, A.; MacKay, W.W. E-mail: mackay@bnl.govhttp://www.rhichome.bnl.gov/People/waldowaldo@bnl.gov; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A.N

    2003-03-01

    In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998, reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to {radical}s=500 GeV.

  6. Spin exchange in polarized deuterium

    International Nuclear Information System (INIS)

    Przewoski, B. von; Meyer, H.O.; Balewski, J.; Doskow, J.; Ibald, R.; Pollock, R.E.; Rinckel, T.; Wellinghausen, A.; Whitaker, T.J.; Daehnick, W.W.; Haeberli, W.; Schwartz, B.; Wise, T.; Lorentz, B.; Rathmann, F.; Pancella, P.V.; Saha, Swapan K.; Thoerngren-Engblom, P.

    2003-01-01

    We have measured the vector and tensor polarization of an atomic deuterium target as a function of the target density. The polarized deuterium was produced in an atomic beam source and injected into a storage cell. For this experiment, the atomic beam source was operated without rf transitions, in order to avoid complications from the unknown efficiency of these transitions. In this mode, the atomic beam is vector and tensor polarized and both polarizations can be measured simultaneously. We used a 1.2-cm-diam and 27-cm-long storage cell, which yielded an average target density between 3 and 9x10 11 at/cm 3 . We find that the tensor polarization decreases with increasing target density while the vector polarization remains constant. The data are in quantitative agreement with the calculated effect of spin exchange between deuterium atoms at low field

  7. Polarization-resolved angular patterns of nematic liquid crystal cells: Topological events driven by incident light polarization

    Science.gov (United States)

    Kiselev, Alexei D.; Vovk, Roman G.; Egorov, Roman I.; Chigrinov, Vladimir G.

    2008-09-01

    We study the angular structure of polarization of light transmitted through a nematic liquid crystal (NLC) cell by analyzing the polarization state as a function of the incidence angles and the polarization of the incident wave. The polarization-resolved angular (conoscopic) patterns emerging after the NLC cell illuminated by the convergent light beam are described in terms of the polarization singularities such as C points (points of circular polarization) and L lines (lines of linear polarization). For the homeotropically aligned cell, the Stokes polarimetry technique is used to measure the polarization resolved conoscopic patterns at different values of the ellipticity of the incident light, γell(inc) , impinging onto the cell. Using the exact analytical expressions for the transfer matrix we show that variations of the ellipticity, γell(inc) , induce transformations of the angular pattern exhibiting the effect of avoided L -line crossings and characterized by topological events such as creation and annihilation of the C points. The predictions of the theory are found to be in good agreement with the experimental results.

  8. Optimal cut-off values for the homeostasis model assessment of insulin resistance (HOMA-IR) and pre-diabetes screening: Developments in research and prospects for the future.

    Science.gov (United States)

    Tang, Qi; Li, Xueqin; Song, Peipei; Xu, Lingzhong

    2015-12-01

    Diabetes mellitus (DM) appears to be increasing rapidly, threatening to reduce life expectancy for humans around the globe. The International Diabetes Federation (IDF) has estimated that there will be 642 million people living with the disease by 2040 and half as many again who will be not diagnosed. This means that pre-DM screening is a critical issue. Insulin resistance (IR) has emerged as a major pathophysiological factor in the development and progression of DM since it is evident in susceptible individuals at the early stages of DM, and particularly type 2 DM (T2DM). Therefore, assessment of IR via the homeostasis model assessment of IR (HOMA-IR) is a key index for the primary prevention of DM and is thus found in guidelines for screening of high-risk groups. However, the cut-off values of HOMA-IR differ for different races, ages, genders, diseases, complications, etc. due to the complexity of IR. This hampers the determination of specific cut-off values of HOMA-IR in different places and in different situations. China has not published an official index to gauge IR for primary prevention of T2DM in the diabetic and non-diabetic population except for children and adolescents ages 6-12 years. Hence, this article summarizes developments in research on IR, HOMA-IR, and pre-DM screening in order to provide a reference for optimal cut-off values of HOMA-IR for the diagnosis of DM in the Chinese population.

  9. Linear polarization of BY Draconis

    International Nuclear Information System (INIS)

    Koch, R.H.; Pfeiffer, R.J.

    1976-01-01

    Linear polarization measurements are reported in four bandpasses for the flare star BY Dra. The red polarization is intrinsically variable at a confidence level greater than 99 percent. On a time scale of many months, the variability is not phase-locked to either a rotational or a Keplerian ephemeris. The observations of the three other bandpasses are useful principally to indicate a polarization spectrum rising toward shorter wavelengths

  10. Polarity in Mammalian Epithelial Morphogenesis

    OpenAIRE

    Roignot, Julie; Peng, Xiao; Mostov, Keith

    2013-01-01

    Cell polarity is fundamental for the architecture and function of epithelial tissues. Epithelial polarization requires the intervention of several fundamental cell processes, whose integration in space and time is only starting to be elucidated. To understand what governs the building of epithelial tissues during development, it is essential to consider the polarization process in the context of the whole tissue. To this end, the development of three-dimensional organotypic cell culture model...

  11. The Complex Resistivity Spectrum Characteristics About Stratabound Sulfide Deposits

    Science.gov (United States)

    Dong, P.; Sun, B.; Wang, L.; Chen, Z.; Dong, Z.; Wu, Y.

    2010-12-01

    Complex resistivity method has become the key technique of deep prospecting, and widely applied in stratabound sulfide deposits which often form massive ores. However, the complex resistivity spectrum characteristics of stratabound sulfide deposits remains unknown. Through studying variation problem of two-dimensional polarization medium, deducing the differential equations and calculating formula,we applied Cole-Cole model to deduce the spectrum of complex resistivity based on the model of three-node and four-node finite element method, and programmed homologous procedure. We utilized the Earth Model of Geological Layers which has accurate analytical solution to test rationality and accuracy of our modeling. We applied the layer structure provided by drilling results in Chenmenshan copper mine,which is typical strata-bound sulfide deposits in Jiangxi province,China, and calculated the spectra of complex resistivity, then made comparison between modeled and measured values. We find good corellation between them. Our studies may have imporved the interpretation of complex resistivity data, which help apply complex resistivity methods of propecting on stratabound sulfide deposites.

  12. Corrosion resistant metallic glasses for biosensing applications

    Science.gov (United States)

    Sagasti, Ariane; Lopes, Ana Catarina; Lasheras, Andoni; Palomares, Verónica; Carrizo, Javier; Gutierrez, Jon; Barandiaran, J. Manuel

    2018-04-01

    We report the fabrication by melt spinning, the magnetic and magnetoelastic characterization and corrosion behaviour study (by potentiodynamic methods) of an Fe-based, Fe-Ni-Cr-Si-B metallic glass to be used as resonant platform for biological and chemical detection purposes. The same study has been performed in Fe-Co-Si-B (with excellent magnetoelastic properties) and Fe-Ni-B (with good corrosion properties due to the substitution of Co by Ni) composition amorphous alloys. The well-known, commercial metallic glass with high corrosion resistance Metglas 2826MB®(Fe40Ni38Mo4B18), widely used for such biological and chemical detection purposes, has been also fully characterized and used as reference. For our Fe-Ni-Cr-Si-B alloy, we have measured values of magnetization (1.22 T), magnetostriction (11.5 ppm) and ΔE effect (6.8 %) values, as well as corrosion potential (-0.25 V), current density (2.54 A/m2), and polarization resistance (56.22 Ω.cm2) that make this composition very promising for the desired biosensing applications. The obtained parameters from our exhaustive characterization are compared with the values obtained for the other different composition metallic glasses and discussed in terms of Ni and Cr content.

  13. Recovering actinide values

    International Nuclear Information System (INIS)

    Horwitz, E.P.; Mason, G.W.

    1980-01-01

    Actinide values are recovered from sodium carbonate scrub waste solutions containing these and other values along with organic compounds resulting from the radiolytic and hydrolytic degradation of neutral organophosphorus extractants such as tri-n butyl phosphate (TBP) and dihexyl-N, N-diethyl carbamylmethylene phosphonate (DHDECMP) which have been used in the reprocessing of irradiated nuclear reactor fuels. The scrub waste solution is made acidic with mineral acid, to form a feed solution which is then contacted with a water-immiscible, highly polar organic extractant which selectively extracts the degradation products from the feed solution. The feed solution can then be processed to recover the actinides for storage or recycled back into the high-level waste process stream. The extractant can be recycled after stripping the degradation products with a neutral sodium carbonate solution. (author)

  14. The SLAC polarized electron source

    International Nuclear Information System (INIS)

    Tang, H.; Alley, R.; Frisch, J.

    1995-06-01

    The SLAC polarized electron source employs a photocathode DC high voltage gun with a loadlock and a YAG pumped Ti:sapphire laser system for colliding beam experiments or a flash lamp pumped Ti:sapphire laser for fixed target experiments. It uses a thin, strained GaAs(100) photocathode, and is capable of producing a pulsed beam with a polarization of ≥80% and a peak current exceeding 10 A. Its operating efficiency has reached 99%. The physics and technology of producing high polarization electron beams from a GaAs photocathode will be reviewed. The prospects of realizing a polarized electron source for future linear colliders will also be discussed

  15. Default values

    International Nuclear Information System (INIS)

    1987-08-01

    In making calculations for the purposes of radiation protection, numerical values for parameters used in the calculations are selected. In some cases, data directly applicable to the set of conditions for which the calculations are to be made are unavailable. Therefore, the selection of the values for these parameters may be based on more general data available from the literature or other sources. These values may be referred to as 'default values', that is, values used in default of those based on directly applicable data. The following policy will be applied by Atomic Energy Control Board (AECB) staff in reviewing the radiation protection aspects of submissions associated with licensing, in participating with other organizations in the development of codes and standards, and in any other work which relies to some extent on using default values

  16. Value Investing

    OpenAIRE

    Liptáková, Lenka

    2014-01-01

    This bachelor's thesis deals with value investing in the form defined by Benjamin Graham. In clarifying the theoretical aspects, particular attention is given to an intrinsic value of stocks and to its calculation methods. A way to overcome the deficiencies in the two most widely used models of calculation is introduced. It is value screening, which by defining of certain criteria makes an assumption of undervalued stocks. Then the investment approach of the most successful investor, Warren B...

  17. An analysis of heat conduction in polar bear hairs using one-dimensional fractional model

    Directory of Open Access Journals (Sweden)

    Zhu Wei-Hong

    2016-01-01

    Full Text Available Hairs of a polar bear are of superior properties such as the excellent thermal protection. The polar bears can perennially live in an extremely cold environment and can maintain body temperature at around 37 °C. Why do polar bears can resist such cold environment? Its membrane-pore structure plays an important role. In the previous work, we established a 1-D fractional heat conduction equation to reveal the hidden mechanism for the hairs. In this paper, we further discuss solutions and parameters of the equation established and analyze heat conduction in polar bear hairs.

  18. Polarization, alignment, and orientation in atomic collisions

    CERN Document Server

    Andersen, Nils

    2017-01-01

    This book covers polarization, alignment, and orientation effects in atomic collisions induced by electron, heavy particle, or photon impact. The first part of the book presents introductory chapters on light and particle polarization, experimental and computational methods, and the density matrix and state multipole formalism. Examples and exercises are included. The second part of the book deals with case studies of electron impact and heavy particle excitation, electron transfer, impact ionization, and autoionization. A separate chapter on photo-induced processes by new-generation light sources has been added. The last chapter discusses related topics and applications. Part III includes examples of charge clouds and introductory summaries of selected seminal papers of tutorial value from the early history of the field (1925 – 1975). The book is a significant update to the previous (first) edition, particularly in experimental and computational methods, the inclusion of key results obtained during the pas...

  19. Which insulin resistance-based definition of metabolic syndrome has superior diagnostic value in detection of poor health-related quality of life? Cross-sectional findings from Tehran Lipid and Glucose Study.

    Science.gov (United States)

    Deihim, Tina; Amiri, Parisa; Taherian, Reza; Tohidi, Maryam; Ghasemi, Asghar; Cheraghi, Leila; Azizi, Fereidoun

    2015-12-09

    The superiority of the diagnostic power of different definitions of metabolic syndrome (MetS) in detecting objective and subjective cardiovascular outcomes is under debate. We sought to compare diagnostic values of different insulin resistance (IR)-based definitions of MetS in detecting poor health-related quality of life (HRQoL) in a large sample of Tehranian adults. This cross-sectional study conducted within the framework of the Tehran Lipid and Glucose Study on a total sample of 742 individuals, aged ≥ 20 years. Metabolic syndrome was defined according to the World Health Organization (WHO), the European Group for the study of Insulin Resistance (EGIR), and the American Association of Clinical Endocrinology (AACE). Health-related quality of life was assessed using the Short Form Health Survey (SF-36). Logistic regression analysis and Receiver Operating Characteristic (ROC) curve were used to investigate the impact of the three IR-based definitions of MetS on HRQoL and compare their discriminative powers in predicting poor HRQoL. Compared with other definitions, the WHO definition identified more participants with MetS (41.8 %). Although the AACE definition had higher adjusted odds ratios for reporting poor physical HRQoL (OR: 1.95; CI: 0.84-4.53 and OR: 1.01; CI: 0.55-1.85 in men and women respectively) and mental HRQoL (OR: 0.97; CI: 0.41-2.28 and OR: 1.00; CI: 0.56-1.79 in men and women respectively), none of the three studied definitions were significantly associated with poor physical or mental HRQoL in either gender; nor did ROC curves show any significant difference in the discriminative powers of IR-based definitions in detecting poor HRQoL in either gender. None of the three studied IR-based definitions of MetS could significantly detect poor HRQoL in the physical or mental domains, indicating no significant superior diagnostic value for any of these definitions.

  20. Forestland values.

    Science.gov (United States)

    John H. Beuter; Ralph J. Alig

    2004-01-01

    This issue of the journal of Forestry is devoted to articles about forestland values. Viewed broadly, natural resources and humans are our two basic resources. An expression of the importance of land as a foundation for forest ecosystems is forestland value. Our attitudes about land and the forest ecosystems that they support have changed considerably in recent years....

  1. Parallel screening of wild-type and drug-resistant targets for anti-resistance neuraminidase inhibitors.

    Directory of Open Access Journals (Sweden)

    Kai-Cheng Hsu

    Full Text Available Infection with influenza virus is a major public health problem, causing serious illness and death each year. Emergence of drug-resistant influenza virus strains limits the effectiveness of drug treatment. Importantly, a dual H275Y/I223R mutation detected in the pandemic influenza A 2009 virus strain results in multidrug resistance to current neuraminidase (NA drugs. Therefore, discovery of new agents for treating multiple drug-resistant (MDR influenza virus infections is important. Here, we propose a parallel screening strategy that simultaneously screens wild-type (WT and MDR NAs, and identifies inhibitors matching the subsite characteristics of both NA-binding sites. These may maintain their potency when drug-resistant mutations arise. Initially, we analyzed the subsite of the dual H275Y/I223R NA mutant. Analysis of the site-moiety maps of NA protein structures show that the mutant subsite has a relatively small volume and is highly polar compared with the WT subsite. Moreover, the mutant subsite has a high preference for forming hydrogen-bonding interactions with polar moieties. These changes may drive multidrug resistance. Using this strategy, we identified a new inhibitor, Remazol Brilliant Blue R (RB19, an anthraquinone dye, which inhibited WT NA and MDR NA with IC(50 values of 3.4 and 4.5 µM, respectively. RB19 comprises a rigid core scaffold and a flexible chain with a large polar moiety. The former interacts with highly conserved residues, decreasing the probability of resistance. The latter forms van der Waals contacts with the WT subsite and yields hydrogen bonds with the mutant subsite by switching the orientation of its flexible side chain. Both scaffolds of RB19 are good starting points for lead optimization. The results reveal a parallel screening strategy for identifying resistance mechanisms and discovering anti-resistance neuraminidase inhibitors. We believe that this strategy may be applied to other diseases with high

  2. Dielectric polarization in random media

    International Nuclear Information System (INIS)

    Ramshaw, J.D.

    1984-01-01

    The theory of dielectric polarization in random media is systematically formulated in terms of response kernels. The primary response kernel K(12) governs the mean dielectric response at the point r 1 to the external electric field at the point r 2 in an infinite system. The inverse of K(12) is denoted by L(12);. it is simpler and more fundamental than K(12) itself. Rigorous expressions are obtained for the effective dielectric constant epsilon( in terms of L(12) and K(12). The latter expression involves the Onsger-Kirkwood function (epsilon(-epsilon 0 (2epsilon(+epsilon 0 )/epsilon 0 epsilon( (where epsilon 0 is an arbitrary reference value), and appears to be new to the random medium context. A wide variety of series representations for epsilon( are generated by means of general perturbation expansions for K(12) and L(12). A discussion is given of certain pitfalls in the theory, most of which are related to the fact that the response kernels are long ranged. It is shown how the dielectric behavior of nonpolar molecular fluids may be treated as a special case of the general theory. The present results for epsilon( apply equally well to other effective phenomenological coefficients of the same generic type, such as thermal and electrical conductivity, magnetic susceptibility, and diffusion coefficients

  3. Polar Biomedical Research - An Assessment.

    Science.gov (United States)

    1982-10-01

    to grow more crops in subpolar Alaska. The severity of the polar conditions in Antarctica allow no practical method for providing volumes of plant food...for an expanded population. Any experiments in polar regions in food production involving geothermal heat, solar energy, hydroponics , or aquaculture

  4. Create a Polarized Light Show.

    Science.gov (United States)

    Conrad, William H.

    1992-01-01

    Presents a lesson that introduces students to polarized light using a problem-solving approach. After illustrating the concept using a slinky and poster board with a vertical slot, students solve the problem of creating a polarized light show using Polya's problem-solving methods. (MDH)

  5. Carbon nanotube fiber terahertz polarizer

    Energy Technology Data Exchange (ETDEWEB)

    Zubair, Ahmed [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Tsentalovich, Dmitri E.; Young, Colin C. [Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005 (United States); Heimbeck, Martin S. [Charles M. Bowden Laboratory, Aviation & Missile Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal, Alabama 35898 (United States); Everitt, Henry O. [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Charles M. Bowden Laboratory, Aviation & Missile Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal, Alabama 35898 (United States); Pasquali, Matteo [Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005 (United States); Department of Chemistry, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Kono, Junichiro, E-mail: kono@rice.edu [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States)

    2016-04-04

    Conventional, commercially available terahertz (THz) polarizers are made of uniformly and precisely spaced metallic wires. They are fragile and expensive, with performance characteristics highly reliant on wire diameters and spacings. Here, we report a simple and highly error-tolerant method for fabricating a freestanding THz polarizer with nearly ideal performance, reliant on the intrinsically one-dimensional character of conduction electrons in well-aligned carbon nanotubes (CNTs). The polarizer was constructed on a mechanical frame over which we manually wound acid-doped CNT fibers with ultrahigh electrical conductivity. We demonstrated that the polarizer has an extinction ratio of ∼−30 dB with a low insertion loss (<0.5 dB) throughout a frequency range of 0.2–1.1 THz. In addition, we used a THz ellipsometer to measure the Müller matrix of the CNT-fiber polarizer and found comparable attenuation to a commercial metallic wire-grid polarizer. Furthermore, based on the classical theory of light transmission through an array of metallic wires, we demonstrated the most striking difference between the CNT-fiber and metallic wire-grid polarizers: the latter fails to work in the zero-spacing limit, where it acts as a simple mirror, while the former continues to work as an excellent polarizer even in that limit due to the one-dimensional conductivity of individual CNTs.

  6. Polarization-preserving holey fibers

    DEFF Research Database (Denmark)

    Broeng, Jes; Mogilevtsev, Dmitri; Libori, Stig E. Barkou

    2001-01-01

    In this work we suggest and discuss a microstructure of air capillaries with elliptical cross-section in a tread of glass that gives opportunity for Creation of polarization-preserving fiber with very small beat length between the fundamental modes of different polarization...

  7. Polarized Scintillating Targets at Psi

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.; Mango, S.

    2001-02-01

    Scintillating polarized targets are now routinely available: blocks of 18×18×5 mm scintillating organic polymer, doped with TEMPO, polarized dynamically in a field of 2.5 T in a vertical 3He-4He dilution refrigerator. A 19 mm diameter plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat.

  8. UV Coatings, Polarization, and Coronagraphy

    Science.gov (United States)

    Bolcar, Matthew R.; Quijada, Manuel; West, Garrett; Balasubramanian, Bala; Krist, John; Martin, Stefan; Sabatke, Derek

    2016-01-01

    Presenation for the Large UltraViolet Optical Infrared (LUVOIR) and Habitable Exoplanet Imager (HabEx) Science and Technology Definition Teams (STDT) on technical considerations regarding ultraviolet coatings, polarization, and coronagraphy. The presentations review the state-of-the-art in ultraviolet coatings, how those coatings generate polarization aberrations, and recent study results from both the LUVOIR and HabEx teams.

  9. Polarization Imaging and Insect Vision

    Science.gov (United States)

    Green, Adam S.; Ohmann, Paul R.; Leininger, Nick E.; Kavanaugh, James A.

    2010-01-01

    For several years we have included discussions about insect vision in the optics units of our introductory physics courses. This topic is a natural extension of demonstrations involving Brewster's reflection and Rayleigh scattering of polarized light because many insects heavily rely on optical polarization for navigation and communication.…

  10. Climate Drives Polar Bear Origins

    Science.gov (United States)

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

  11. Coexistence of antiferromagnetism and spin polarization in double perovskite SrLaVMoO6

    International Nuclear Information System (INIS)

    Asano, H; Gotoh, H; Matsushima, H; Takeda, Y; Zhong, J; Rajanikanth, A; Hono, K

    2010-01-01

    The magnetic and transport properties of SrLaVMoO 6 bulk samples with an ordered double perovskite structure have been investigated. Magnetization measurements have indicated that the SrLaVMoO 6 compound exhibits a cusp at 125 K, which is attributable to an antiferromagnetic transition. Electrical resistivity ρ for the compound showed metallic temperature dependence from 10 to 300 K, and a spin polarization P value was measured to be 0.50 using the point-contact Andreev reflection (PCAR) technique. It has been found from X-ray photoemission spectroscopy (XPS) study that SrLaVMoO 6 closely resembles the half-metallic Sr 2 FeMoO 6 in the electronic state of the Mo.

  12. Integrins and epithelial cell polarity.

    Science.gov (United States)

    Lee, Jessica L; Streuli, Charles H

    2014-08-01

    Cell polarity is characterised by differences in structure, composition and function between at least two poles of a cell. In epithelial cells, these spatial differences allow for the formation of defined apical and basal membranes. It has been increasingly recognised that cell-matrix interactions and integrins play an essential role in creating epithelial cell polarity, although key gaps in our knowledge remain. This Commentary will discuss the mounting evidence for the role of integrins in polarising epithelial cells. We build a model in which both inside-out signals to polarise basement membrane assembly at the basal surface, and outside-in signals to control microtubule apical-basal orientation and vesicular trafficking are required for establishing and maintaining the orientation of epithelial cell polarity. Finally, we discuss the relevance of the basal integrin polarity axis to cancer. This article is part of a Minifocus on Establishing polarity. © 2014. Published by The Company of Biologists Ltd.

  13. Hyperon polarization: An experimental overview

    International Nuclear Information System (INIS)

    Lach, J.

    1992-12-01

    The fact that inclusively produced hyperons are produced with significant polarization was first discovered at Fermilab about seventeen years ago. This and subsequent experiments showed that Λ degree were produced polarized while bar Λ degree had no polarization in the same kinematical region. This set the stage for many experiments which showed that most hyperons are produced polarized. Recent Fermilab experiments have showed that this phenomena is even more complex than previously thought and theoretical understanding is still lacking. Nevertheless polarized hyperon beams have been an extremely useful experimental tool in measuring hyperon magnetic moments and hyperon β-decay. Recently, hyperon radiative decays have been studied and magnetic moment precession of channeled particles in bent crystals has been observed

  14. A review of polarized ion sources

    International Nuclear Information System (INIS)

    Schmor, P.W.

    1995-06-01

    The two main types of polarized ion sources in use on accelerators today are the Atomic Beam Polarized Ion Source (ABIS) source and the Optically Pumped Polarized Ion Source (OPPIS). Both types can provide beams of nuclearly polarized light ions which are either positively or negatively charged. Heavy ion polarized ion sources for accelerators are being developed. (author). 35 refs., 1 tab

  15. Promoting Diversity Through Polar Interdisciplinary Coordinated Education (Polar ICE)

    Science.gov (United States)

    McDonnell, J. D.; Hotaling, L. A.; Garza, C.; Van Dyk, P. B.; Hunter-thomson, K. I.; Middendorf, J.; Daniel, A.; Matsumoto, G. I.; Schofield, O.

    2017-12-01

    Polar Interdisciplinary Coordinated Education (ICE) is an education and outreach program designed to provide public access to the Antarctic and Arctic regions through polar data and interactions with the scientists. The program provides multi-faceted science communication training for early career scientists that consist of a face-to face workshop and opportunities to apply these skills. The key components of the scientist training workshop include cultural competency training, deconstructing/decoding science for non-expert audiences, the art of telling science stories, and networking with members of the education and outreach community and reflecting on communication skills. Scientists partner with educators to provide professional development for K-12 educators and support for student research symposia. Polar ICE has initiated a Polar Literacy initiative that provides both a grounding in big ideas in polar science and science communication training designed to underscore the importance of the Polar Regions to the public while promoting interdisciplinary collaborations between scientists and educators. Our ultimate objective is to promote STEM identity through professional development of scientists and educators while developing career awareness of STEM pathways in Polar science.

  16. The Value of Value Sets

    DEFF Research Database (Denmark)

    Sløk-Madsen, Stefan Kirkegaard; Christensen, Jesper

    The world over classrooms in business schools are being taught that corporate values can impact performance. The argument is typically that culture matter more than strategy plans and culture can be influenced and indeed changed by a shared corporate value set. While the claim seems intuitively...

  17. Values Research

    Science.gov (United States)

    2009-10-01

    that individualistic employees in individualistic organizations and collectivistic employees in collectivistic organizations show greater job...fit subsumes needs-supplies and demands-abilities perspectives . 38 Values and Retention Relationship among different conceptualizations of P-E

  18. Optical Polarization Modulation and Gain Anisotropy in an Electrically Injected Spin Laser

    Science.gov (United States)

    Basu, D.; Saha, D.; Bhattacharya, P.

    2009-03-01

    The effects of spin-induced gain anisotropy on output polarization and threshold current reduction of electrically pumped spin-polarized lasers have been studied. Analytical forms of these parameters are derived by considering diffusive transport from the spin injector to the active region. The calculated values of the parameter are in excellent agreement with values obtained from measurements made at 200 K on an InAs/GaAs quantum dot spin-polarized vertical cavity surface-emitting laser. Electrical modulation of the output polarization of the laser is demonstrated with a peak modulation index of 0.6.

  19. Unravelling Value

    DEFF Research Database (Denmark)

    Walsh, Matthew

    Paper presented in the symposium “What’s It All Worth? Material Possessions and Value in Past Societies” at 22nd Annual Meeting of the European Association of Archaeologists, Vilnius, Lithuania.......Paper presented in the symposium “What’s It All Worth? Material Possessions and Value in Past Societies” at 22nd Annual Meeting of the European Association of Archaeologists, Vilnius, Lithuania....

  20. The effect of Electro Discharge Machining (EDM) on the corrosion resistance of dental alloys.

    Science.gov (United States)

    Ntasi, Argyro; Mueller, Wolf Dieter; Eliades, George; Zinelis, Spiros

    2010-12-01

    The aim of the present study was to evaluate the effect of Electro Discharge Machining (EDM) on the corrosion resistance of two types of dental alloys used for fabrication of implant retained superstructures. Two groups of specimens were prepared from a Co-Cr (Okta-C) and a grade II cpTi (Biotan) alloys respectively. Half of the specimens were subjected to EDM with Cu electrodes and the rest were conventionally finished (CF). The corrosion resistance of the alloys was evaluated by anodic polarization in Ringer's solution. Morphological and elemental alterations before and after corrosion testing were studied by SEM/EDX. Six regions were analyzed on each surface before and after corrosion testing and the results were statistically analyzed by paired t-test (a=0.05). EDM demonstrated inferior corrosion resistance compared to CF surfaces, the latter being passive in a wider range of potential demonstrating higher polarization resistance and lower I(corr) values. Morphological alterations were found before and after corrosion testing for both materials tested after SEM analysis. EDX showed a significant decrease in Mo, Cr, Co, Cu (Co-Cr) and Ti, Cu (cpTi) after electrochemical testing plus an increase in C. According to the results of this study the EDM procedure decreases the corrosion resistance of both the alloys tested, increasing thus the risk of possible adverse biological reactions. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  1. Characterization of the internal resistance of a plant microbial fuel cell

    NARCIS (Netherlands)

    Timmers, R.A.; Strik, D.P.B.T.B.; Hamelers, H.V.M.; Buisman, C.J.N.

    2012-01-01

    The objective of this research was to clarify the internal resistance of the PMFC. To characterize internal resistances of the PMFC current interrupt and polarization were used, and partial resistances were calculated. The internal resistance consisted mainly of anode resistance and membrane

  2. POLARIZED LIGHT IN PHYSIOTHERAPY

    Directory of Open Access Journals (Sweden)

    L. D. Tondiy

    2015-12-01

    Full Text Available The data on polarized light (PS - a new promising treatment, rehabilitation and prevention, which took its deserved place among the known therapeutic physical factors and may even compete with laser radiation of low and LED therapy. It is reflected the significant contribution of domestic scientists in the study of aircraft action on the body, its introduction in the treatment, rehabilitation and prevention of grippe, ARI. These action's mechanisms of the aircraft on the electro-physiological processes in the body that have the leading role in the regulation of its life. The new moment in the study of aircraft on the body is the evidence of its positive impact on the mechanisms of self body - its different units: the disease's banning - a revitalization of the stress-protective, stress-limiting system antioxidial, detoxification and other protection systems, the formation by the body antiviral and antimicrobial specific substances (interferon and lysozyme, activation of the immune system, phagocytosis, protective functions of skin. The protective and mobilizing role of the second link is studied: which is triggered in case of occurrence of disease or preexisting diseases: PL mobilized processes of restitution, reparations, compensation, immunity and microcirculation. The authors studied the possibility of aircraft's using to enhance performance, reduce side effects of physical factors, which are often used in the treatment (electric methods, treatment by sound, fresh and mineral water, etc..

  3. Update of the Polar SWIFT model for polar stratospheric ozone loss (Polar SWIFT version 2)

    Science.gov (United States)

    Wohltmann, Ingo; Lehmann, Ralph; Rex, Markus

    2017-07-01

    The Polar SWIFT model is a fast scheme for calculating the chemistry of stratospheric ozone depletion in polar winter. It is intended for use in global climate models (GCMs) and Earth system models (ESMs) to enable the simulation of mutual interactions between the ozone layer and climate. To date, climate models often use prescribed ozone fields, since a full stratospheric chemistry scheme is computationally very expensive. Polar SWIFT is based on a set of coupled differential equations, which simulate the polar vortex-averaged mixing ratios of the key species involved in polar ozone depletion on a given vertical level. These species are O3, chemically active chlorine (ClOx), HCl, ClONO2 and HNO3. The only external input parameters that drive the model are the fraction of the polar vortex in sunlight and the fraction of the polar vortex below the temperatures necessary for the formation of polar stratospheric clouds. Here, we present an update of the Polar SWIFT model introducing several improvements over the original model formulation. In particular, the model is now trained on vortex-averaged reaction rates of the ATLAS Chemistry and Transport Model, which enables a detailed look at individual processes and an independent validation of the different parameterizations contained in the differential equations. The training of the original Polar SWIFT model was based on fitting complete model runs to satellite observations and did not allow for this. A revised formulation of the system of differential equations is developed, which closely fits vortex-averaged reaction rates from ATLAS that represent the main chemical processes influencing ozone. In addition, a parameterization for the HNO3 change by denitrification is included. The rates of change of the concentrations of the chemical species of the Polar SWIFT model are purely chemical rates of change in the new version, whereas in the original Polar SWIFT model, they included a transport effect caused by the

  4. Microstructural evolution and pitting resistance of annealed lean duplex stainless steel UNS S32304

    International Nuclear Information System (INIS)

    Zhang Ziying; Han Dong; Jiang Yiming; Shi Chong; Li Jin

    2012-01-01

    Highlights: ► The relationship between pitting corrosion resistance and annealing temperature for UNS S32304 was systemically studied. ► The specimens annealed at 1080 °C for 1 h, quenched in water exhibit the best pitting corrosion resistance. ► The relationship between microstructural evolution and pitting resistance of annealed UNS S32304 was discussed in detail. ► The pitting corrosion resistance is consistent with pitting resistance equivalent number of weaker phase for UNS S32304 alloy. - Abstract: The effect of annealing temperature in the range from 1000 to 1200 °C on the pitting corrosion behavior of duplex stainless steel UNS S32304 was investigated by the potentiodynamic polarization and potentiostatic critical pitting temperature techniques. The microstructural evolution and pit morphologies were studied using a scanning electron microscopy with energy dispersive X-ray spectroscopy. The results demonstrated that the nucleation of metastable pits transformed from austenite phase to ferrite phase with the increasing annealing temperature. As the annealing temperature increased, the pitting corrosion resistance firstly increased and then decreased. The highest pitting corrosion resistance was obtained at 1080 °C with the highest critical pitting temperature value and pitting nucleation resistance. The results could be well explained by the microstructural evolution of ferrite and austenite phases induced by annealing treatment.

  5. Electrode polarization vs. Maxwell-Wagner-Sillars interfacial polarization in dielectric spectra of materials: Characteristic frequencies and scaling laws

    Science.gov (United States)

    Samet, M.; Levchenko, V.; Boiteux, G.; Seytre, G.; Kallel, A.; Serghei, A.

    2015-05-01

    The characteristic frequencies of electrode polarization and of interfacial polarization effects in dielectric spectra of ionic liquids and of polymer bi-layers are determined and systematically analyzed, based on dielectric measurements by means of broadband dielectric spectroscopy, numerical simulations, and analytical calculations. It is shown that, to a large extent, identical scaling laws can be derived for these two dielectric phenomena taking place at external and internal interfaces. Surprisingly, a fundamentally different behavior concerning the interrelation between the characteristic frequencies is found. This brings direct evidence that different manifestations of the phenomenon of electrical polarization can be discriminated by examining the inter-relation governing their characteristic frequencies, which can be of significant importance in disseminating the nature of different contributions appearing in the dielectric spectra of complex materials. Based on our analysis, we derive a new formula, valid for both electrode polarization and interfacial polarization effects, that allows one to determine the conductivity value from the frequency position of the Maxwell-Wagner-Sillars peak. An excellent agreement between experiment and calculations is obtained. The formula can be used, furthermore, to estimate the thickness of the interfacial layers formed due to electrode polarization effects. Values in the order of several nanometers, increasing with decreasing temperature, are reported.

  6. Nuclear physics with polarized particles

    CERN Document Server

    Paetz gen Schieck, Hans

    2012-01-01

    The measurement of spin-polarization observables in reactions of nuclei and particles is of great utility and advantage when the effects of single-spin sub-states are to be investigated. Indeed, the unpolarized differential cross-section encompasses the averaging over the spin states of the particles, and thus loses details of the interaction process. This introductory text combines, in a single volume, course-based lecture notes on spin physics and on polarized-ion sources with the aim of providing a concise yet self-contained starting point for newcomers to the field, as well as for lecturers in search of suitable material for their courses and seminars. A significant part of the book is devoted to introducing the formal theory-a description of polarization and of nuclear reactions with polarized particles. The remainder of the text describes the physical basis of methods and devices necessary to perform experiments with polarized particles and to measure polarization and polarization effects in nuclear rea...

  7. Few-body experiments with polarized beams and polarized targets

    International Nuclear Information System (INIS)

    Simmons, J.E.

    1983-01-01

    A survey is presented concerning recent polarization experiments in the elastic p-d, p- 3 He, and p- 4 He systems. Mention is made of selected neutron experiments. The nominal energy range is 10 to 1000 MeV. Recent results and interpretations of the p-d system near 10 MeV are discussed. New experiments on the energy dependence of back angle p-d tensor polarization are discussed with respect to resolution of discrepancies and difficulty of theoretical interpretation. Progress is noted concerning multiple scattering interpretation of forward p-d deuteron polarization. Some new results are presented concerning the p- 3 He system and higher energy p- 4 He polarization experiments. 52 references

  8. Bipolar resistive switching and charge transport in silicon oxide memristor

    Energy Technology Data Exchange (ETDEWEB)

    Mikhaylov, Alexey N., E-mail: mian@nifti.unn.ru [Lobachevsky State University of Nizhni Novgorod, 23/3 Gagarin Prospect, Nizhni Novgorod 603950 (Russian Federation); Belov, Alexey I.; Guseinov, Davud V.; Korolev, Dmitry S.; Antonov, Ivan N.; Efimovykh, Denis V.; Tikhov, Stanislav V.; Kasatkin, Alexander P.; Gorshkov, Oleg N.; Tetelbaum, David I.; Bobrov, Alexander I.; Malekhonova, Natalia V.; Pavlov, Dmitry A. [Lobachevsky State University of Nizhni Novgorod, 23/3 Gagarin Prospect, Nizhni Novgorod 603950 (Russian Federation); Gryaznov, Evgeny G. [Lobachevsky State University of Nizhni Novgorod, 23/3 Gagarin Prospect, Nizhni Novgorod 603950 (Russian Federation); Sedakov Scientific-Research Institute, GSP-486, Nizhny Novgorod 603950 (Russian Federation); Yatmanov, Alexander P. [Sedakov Scientific-Research Institute, GSP-486, Nizhny Novgorod 603950 (Russian Federation)

    2015-04-15

    Graphical abstract: - Highlights: • Si-based thin-film memristor structure was fabricated by magnetron sputtering. • We study bipolar resistive switching and charge transport mechanisms. • Resistive switching parameters are determined by a balance between redox reactions. - Abstract: Reproducible bipolar resistive switching has been studied in SiO{sub x}-based thin-film memristor structures deposited by magnetron sputtering technique on the TiN/Ti metalized SiO{sub 2}/Si substrates. It is established that, after electroforming, the structure can be switched between the quasi-ohmic low-resistance state related to silicon chains (conducting filaments) and the high-resistance state with semiconductor-like hopping mechanism of charge transport through the defects in silicon oxide. The switching parameters are determined by a balance between the reduction and oxidation processes that, in turn, are driven by the value and polarity of voltage bias, current, temperature and device environment. The results can be used for the development of silicon-based nonvolatile memory and memristive systems as a key component of future electronics.

  9. Resistance-resistant antibiotics.

    Science.gov (United States)

    Oldfield, Eric; Feng, Xinxin

    2014-12-01

    New antibiotics are needed because drug resistance is increasing while the introduction of new antibiotics is decreasing. We discuss here six possible approaches to develop 'resistance-resistant' antibiotics. First, multitarget inhibitors in which a single compound inhibits more than one target may be easier to develop than conventional combination therapies with two new drugs. Second, inhibiting multiple targets in the same metabolic pathway is expected to be an effective strategy owing to synergy. Third, discovering multiple-target inhibitors should be possible by using sequential virtual screening. Fourth, repurposing existing drugs can lead to combinations of multitarget therapeutics. Fifth, targets need not be proteins. Sixth, inhibiting virulence factor formation and boosting innate immunity may also lead to decreased susceptibility to resistance. Although it is not possible to eliminate resistance, the approaches reviewed here offer several possibilities for reducing the effects of mutations and, in some cases, suggest that sensitivity to existing antibiotics may be restored in otherwise drug-resistant organisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Elite Polarization and Public Opinion

    DEFF Research Database (Denmark)

    Robison, Joshua; Mullinix, Kevin

    2016-01-01

    Elite polarization has reshaped American politics and is an increasingly salient aspect of news coverage within the United States. As a consequence, a burgeoning body of research attempts to unravel the effects of elite polarization on the mass public. However, we know very little about how...... attitudes. In our first study, we show that criticism of polarization leads partisans to more positively evaluate the argument offered by their non-preferred party, increases support for bi-partisanship, but ultimately does not change the extent to which partisans follow their party’s policy endorsements...

  11. Acceleration of polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1998-01-01

    The acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian snakes are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator

  12. Polarimetry with azimuthally polarized light

    Science.gov (United States)

    de Sande, Juan Carlos González; Piquero, Gemma; Santarsiero, Massimo

    2018-03-01

    Nonuniformly polarized light can be used for Mueller polarimetry of homogeneous linear samples. In this work, a set up based on using azimuthally polarized input light and a modified commercial light polarimeter is proposed and developed. With this set up, a Mueller submatrix of a sample can be obtained by measuring the Stokes parameters at only three different positions across the output beam section. Symmetry constraints for linear deterministic samples allow the complete Mueller matrix to be deduced for this kind of specimens. The experimental results obtained for phase plates and for a linear polarizer confirm the validity of the proposed method.

  13. Polarized deuteron elastic scattering from a polarized proton target

    International Nuclear Information System (INIS)

    Schmelzer, R.; Kuiper, H.; Schoeberl, M.; Berber, S.; Hilmert, H.; Koeppel, R.; Pferdmenges, R.; Zankel, H.

    1983-01-01

    Measurements are reported of the spin correlation parameter Cy,y for the elastic scattering of 10.0 MeV vector polarized deuterons from a polarized proton target at five CM angles (76 0 ,85 0 ,98 0 ,115 0 ,132 0 ). The experimental results are compared with different predictions. A Faddeev type calculation on the basis of local potentials also including approximate Coulomb distortion is favoured by our experimental results. (orig.)

  14. PolarHub: A Global Hub for Polar Data Discovery

    Science.gov (United States)

    Li, W.

    2014-12-01

    This paper reports the outcome of a NSF project in developing a large-scale web crawler PolarHub to discover automatically the distributed polar dataset in the format of OGC web services (OWS) in the cyberspace. PolarHub is a machine robot; its goal is to visit as many webpages as possible to find those containing information about polar OWS, extract this information and store it into the backend data repository. This is a very challenging task given huge data volume of webpages on the Web. Three unique features was introduced in PolarHub to make it distinctive from earlier crawler solutions: (1) a multi-task, multi-user, multi-thread support to the crawling tasks; (2) an extensive use of thread pool and Data Access Object (DAO) design patterns to separate persistent data storage and business logic to achieve high extendibility of the crawler tool; (3) a pattern-matching based customizable crawling algorithm to support discovery of multi-type geospatial web services; and (4) a universal and portable client-server communication mechanism combining a server-push and client pull strategies for enhanced asynchronous processing. A series of experiments were conducted to identify the impact of crawling parameters to the overall system performance. The geographical distribution pattern of all PolarHub identified services is also demonstrated. We expect this work to make a major contribution to the field of geospatial information retrieval and geospatial interoperability, to bridge the gap between data provider and data consumer, and to accelerate polar science by enhancing the accessibility and reusability of adequate polar data.

  15. Polarization diversity scheme on spectral polarization coding optical code-division multiple-access network

    Science.gov (United States)

    Yen, Chih-Ta; Huang, Jen-Fa; Chang, Yao-Tang; Chen, Bo-Hau

    2010-12-01

    We present an experiment demonstrating the spectral-polarization coding optical code-division multiple-access system introduced with a nonideal state of polarization (SOP) matching conditions. In the proposed system, the encoding and double balanced-detection processes are implemented using a polarization-diversity scheme. Because of the quasiorthogonality of Hadamard codes combining with array waveguide grating routers and a polarization beam splitter, the proposed codec pair can encode-decode multiple code words of Hadamard code while retaining the ability for multiple-access interference cancellation. The experimental results demonstrate that when the system is maintained with an orthogonal SOP for each user, an effective reduction in the phase-induced intensity noise is obtained. The analytical SNR values are found to overstate the experimental results by around 2 dB when the received effective power is large. This is mainly limited by insertion losses of components and a nonflattened optical light source. Furthermore, the matching conditions can be improved by decreasing nonideal influences.

  16. Dietary biomagnification of organochlorine contaminants in Alaskan polar bears

    Science.gov (United States)

    Bentzen, T.W.; Follmann, Erich H.; Amstrup, Steven C.; York, G.S.; Wooller, M.J.; Muir, D.C.G.; O'Hara, T. M.

    2008-01-01

    Concentrations of organochlorine contaminants in the adipose tissue of polar bears (Ursus maritimus Phipps, 1774) vary throughout the Arctic. The range in concentrations has not been explained fully by bear age, sex, condition, location, or reproductive status. Dietary pathways expose polar bears to a variety of contaminant profiles and concentrations. Prey range from lower trophic level bowhead whales (Balaena mysticetus L., 1758), one of the least contaminated marine mammals, to highly contaminated upper trophic level ringed seals (Phoca hispida (Schreber, 1775)). We used ??15N and ??13C signatures to estimate the trophic status of 42 polar bears sampled along Alaska's Beaufort Sea coast to determine the relationship between organochlorine concentration and trophic level. The ?? 15N values in the cellular portions of blood ranged from 18.2% to 20.7%. We found strong positive relationships between concentrations of the most recalcitrant polychlorinated biphenyls (PCBs) and ??15N values in models incorporating age, lipid content, and ??13C value. Specifically these models accounted for 67% and 76% of the variation in PCB153 and oxychlordane concentration in male polar bears and 85% and 93% in females, respectively. These results are strong indicators of variation in diet and biomagnification of organochlorines among polar bears related to their sex, age, and trophic position. ?? 2008 NRC.

  17. Chemical passivation as a method of improving the electrochemical corrosion resistance of Co-Cr-based dental alloy.

    Science.gov (United States)

    Rylska, Dorota; Sokołowski, Grzegorz; Sokołowski, Jerzy; Łukomska-Szymańska, Monika

    2017-01-01

    The purpose of the study was to evaluate corrosion resistance of Wirobond C® alloy after chemical passivation treatment. The alloy surface undergone chemical passivation treatment in four different media. Corrosion studies were carried out by means of electrochemical methods in saline solution. Corrosion effects were determined using SEM. The greatest increase in the alloy polarization resistance was observed for passive layer produced in Na2SO4 solution with graphite. The same layer caused the highest increase in corrosion current. Generally speaking, the alloy passivation in Na2SO4 solution with graphite caused a substantial improvement of the corrosion resistance. The sample after passivation in Na2SO4 solution without graphite, contrary to others, lost its protective properties along with successive anodic polarization cycles. The alloy passivation in Na3PO4 solution with graphite was the only one that caused a decrease in the alloy corrosion properties. The SEM studies of all samples after chemical passivation revealed no pit corrosion - in contrast to the sample without any modification. Every successive polarization cycle in anodic direction of pure Wirobond C® alloy enhances corrosion resistance shifting corrosion potential in the positive direction and decreasing corrosion current value. The chemical passivation in solutions with low pH values decreases susceptibility to electrochemical corrosion of Co-Cr dental alloy. The best protection against corrosion was obtained after chemical passivation of Wirobond C® in Na2SO4 solution with graphite. Passivation with Na2SO4 in solution of high pH does not cause an increase in corrosion resistance of WIROBOND C. Passivation process increases alloy resistance to pit corrosion.

  18. The addition of Si to the Ti–35Nb alloy and its effect on the corrosion resistance, when applied to biomedical materials

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, A.M.G.; Fernandes, B.S.; Souza, S.A.; Batista, W.W.; Cunha, F.G.C. [Department of Materials Science and Engineering, Federal University of Sergipe, 49100-000 São Cristóvão, SE (Brazil); Landers, R. [Institute of Physics Gleb Wataghin, State University of Campinas – UNICAMP, 13083-859 Campinas, SP (Brazil); Macedo, M.C.S.S., E-mail: michellecardinales@gmail.com [Department of Materials Science and Engineering, Federal University of Sergipe, 49100-000 São Cristóvão, SE (Brazil)

    2014-04-05

    Highlights: • An investigation of the corrosion resistance of Ti–Nb–Si was proposed. • The study was based on polarization curves, OCP, electrochemical impedance, XPS. • The addition of Si to 0.35% increased the corrosion resistance of the alloys. • Data suggest that the studied alloys are promising for biomedical applications. -- Abstract: Alloy elements such as niobium and silicon have been added to titanium as an alternative for new materials to be used in orthopedic implants once they present biocompatibility and favor reductions in the elastic modulus. However, these new materials’ behavior, in face of corrosion is still demanding careful investigations because they will be subjected to an aggressive environ, such as the human body. The corrosion resistance of the Ti–35Nb–(0; 0.15; 0.35; 0.55)Si (% in mass) when in physiological medium was assessed by means of polarization curves, open circuit potential and electrochemical impedance spectroscopy. The compositions of the passive films were analyzed by X-ray photoelectron spectroscopy (XPS). Outcomes show that the alloys presented good rapid repassivation capacity after film breaking under high potentials. The high values of resistance to polarization – Rp – pinpoint that the formed oxide films are resistive. They work as a protecting barrier against aggressive ions. Data suggest that the studied alloys are promising for orthopedic implant applications.

  19. A New Concept for Non-Volatile Memory: The Electric-Pulse Induced Resistive Change Effect in Colossal Magnetoresistive Thin Films

    Science.gov (United States)

    Liu, S. Q.; Wu, N. J.; Ignatiev, A.

    2001-01-01

    A novel electric pulse-induced resistive change (EPIR) effect has been found in thin film colossal magnetoresistive (CMR) materials, and has shown promise for the development of resistive, nonvolatile memory. The EPIR effect is induced by the application of low voltage (resistance of the thin film sample depending on pulse polarity. The sample resistance change has been shown to be over two orders of magnitude, and is nonvolatile after pulsing. The sample resistance can also be changed through multiple levels - as many as 50 have been shown. Such a device can provide a way for the development of a new kind of nonvolatile multiple-valued memory with high density, fast write/read speed, low power-consumption, and potential high radiation-hardness.

  20. Polar source analysis : technical memorandum

    Science.gov (United States)

    2017-09-29

    The following technical memorandum describes the development, testing and analysis of various polar source data sets. The memorandum also includes recommendation for potential inclusion in future releases of AEDT. This memorandum is the final deliver...

  1. The definition of cross polarization

    DEFF Research Database (Denmark)

    Ludwig, Arthur

    1973-01-01

    There are at least three different definitions of cross polarization used in the literature. The alternative definitions are discussed with respect to several applications, and the definition which corresponds to one standard measurement practice is proposed as the best choice....

  2. Dynamic elections and ideological polarization

    Czech Academy of Sciences Publication Activity Database

    Nunnari, S.; Zápal, Jan

    2017-01-01

    Roč. 25, č. 4 (2017), s. 505-534 ISSN 1047-1987 Institutional support: Progres-Q24 Keywords : elections * political polarization Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 3.361, year: 2016

  3. Dynamic elections and ideological polarization

    Czech Academy of Sciences Publication Activity Database

    Nunnari, S.; Zápal, Jan

    2017-01-01

    Roč. 25, č. 4 (2017), s. 505-534 ISSN 1047-1987 Institutional support: RVO:67985998 Keywords : elections * political polarization Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 3.361, year: 2016

  4. Polarization at LEP. Vol. 2

    International Nuclear Information System (INIS)

    Alexander, G.; Altarelli, G.; Blondel, A.; Coignet, G.; Keil, E.; Plane, D.E.; Treille, D.

    1988-01-01

    This report contains a collection of papers covering the most important part of studies carried out by five study groups in view of a programme of experiments with polarized beams at LEP, the Large Electron-Positron collider under construction at CERN. The emphasis is on precision measurements at the Z peak. Such measurements are shown to be of considerable theoretical interest as well as very clean from the point of view of theoretical and experimental uncertainties. The measurement of the beam polarization can certainly be performed with sufficient accuracy, thanks to the availability of both e + and e - beam polarization. The normalization of the data taken with different beam helicities poses certain constraints that are described. Substantial progress has been made in understanding the possibility of providing longitudinally polarized beams in the LEP machine: The design of new wigglers and spin rotators, the study of correction procedures and results of numerical simulations are presented. (orig.)

  5. Mechanical writing of ferroelectric polarization.

    Science.gov (United States)

    Lu, H; Bark, C-W; Esque de los Ojos, D; Alcala, J; Eom, C B; Catalan, G; Gruverman, A

    2012-04-06

    Ferroelectric materials are characterized by a permanent electric dipole that can be reversed through the application of an external voltage, but a strong intrinsic coupling between polarization and deformation also causes all ferroelectrics to be piezoelectric, leading to applications in sensors and high-displacement actuators. A less explored property is flexoelectricity, the coupling between polarization and a strain gradient. We demonstrate that the stress gradient generated by the tip of an atomic force microscope can mechanically switch the polarization in the nanoscale volume of a ferroelectric film. Pure mechanical force can therefore be used as a dynamic tool for polarization control and may enable applications in which memory bits are written mechanically and read electrically.

  6. Mechanical Writing of Ferroelectric Polarization

    Science.gov (United States)

    Lu, H.; Bark, C.-W.; Esque de los Ojos, D.; Alcala, J.; Eom, C. B.; Catalan, G.; Gruverman, A.

    2012-04-01

    Ferroelectric materials are characterized by a permanent electric dipole that can be reversed through the application of an external voltage, but a strong intrinsic coupling between polarization and deformation also causes all ferroelectrics to be piezoelectric, leading to applications in sensors and high-displacement actuators. A less explored property is flexoelectricity, the coupling between polarization and a strain gradient. We demonstrate that the stress gradient generated by the tip of an atomic force microscope can mechanically switch the polarization in the nanoscale volume of a ferroelectric film. Pure mechanical force can therefore be used as a dynamic tool for polarization control and may enable applications in which memory bits are written mechanically and read electrically.

  7. The {sup 68}Ga/{sup 177}Lu theragnostic concept in PSMA targeting of castration-resistant prostate cancer: correlation of SUV{sub max} values and absorbed dose estimates

    Energy Technology Data Exchange (ETDEWEB)

    Scarpa, Lorenza; Buxbaum, Sabine; Kendler, Dorota; Decristoforo, Clemens; Uprimny, Christian; Virgolini, Irene [Medical University Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Fink, Katharina [Medical University Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Medical University of Innsbruck, Department of Radiotherapy / Radiation Oncology, Innsbruck (Austria); Bektic, Jasmin; Horninger, Wolfgang [Medical University of Innsbruck, Department of Urology, Innsbruck (Austria); Gruber, Leonhard [Medical University of Innsbruck, Department of Radiology, Innsbruck (Austria); Lukas, Peter [Medical University of Innsbruck, Department of Radiotherapy / Radiation Oncology, Innsbruck (Austria)

    2017-05-15

    A targeted theragnostic approach based on increased expression of prostate-specific membrane antigen (PSMA) on PC cells is an attractive treatment option for patients with metastatic castration-resistant prostate cancer (mCRPC). Ten consecutive mCRPC patients were selected for {sup 177}Lu-PSMA617 therapy on the basis of PSMA-targeted {sup 68}Ga-PSMA-HBED-CC PET/CT diagnosis showing extensive and progressive tumour load. Following dosimetry along with the first therapy cycle restaging ({sup 68}Ga-PSMA-HBED-CC and {sup 18}F-NaF PET/CT) was performed after 2 and 3 therapy cycles (each 6.1 ± 0.3 GBq, range 5.4-6.5 GBq) given intravenously over 30 minutes, 9 ± 1 weeks apart. PET/CT scans were compared to {sup 177}Lu-PSMA617 24-hour whole-body scans and contrast-enhanced dual-phase CT. Detailed comparison of SUVmax values and absorbed tumour doses was performed. {sup 177}Lu-PSMA617 dosimetry indicated high tumour doses for skeletal (3.4 ± 1.9 Gy/GBq; range 1.1-7.2 Gy/GBq), lymph node (2.6 ± 0.4 Gy/GBq; range 2.3-2.9 Gy/GBq) as well as liver (2.4 ± 0.8 Gy/GBq; range 1.7-3.3 Gy/GBq) metastases whereas the dose for tissues/organs was acceptable in all patients for an intention-to-treat activity of 18 ± 0.3 GBq. Three patients showed partial remission, three mixed response, one stable and three progressive disease. Decreased {sup 177}Lu-PSMA617 and {sup 68}Ga-PSMA-HBED-CC uptake (mean SUVmax values 20.2 before and 15.0 after 2 cycles and 11.5 after 3 cycles, p < 0.05) was found in 41/54 skeletal lesions, 12/13 lymph node metastases, 3/5 visceral metastases and 4/4 primary PC lesions. Due to substantial individual variance, dosimetry is mandatory for a patient-specific approach following {sup 177}Lu-PSMA617 therapy. Higher activities and/or shorter treatment intervals should be applied in a larger prospective study. (orig.)

  8. Modeling optical and UV polarization of AGNs. IV. Polarization timing

    Science.gov (United States)

    Rojas Lobos, P. A.; Goosmann, R. W.; Marin, F.; Savić, D.

    2018-03-01

    Context. Optical observations cannot resolve the structure of active galactic nuclei (AGN), and a unified model for AGN was inferred mostly from indirect methods, such as spectroscopy and variability studies. Optical reverberation mapping allowed us to constrain the spatial dimension of the broad emission line region and thereby to measure the mass of supermassive black holes. Recently, reverberation was also applied to the polarized signal emerging from different AGN components. In principle, this should allow us to measure the spatial dimensions of the sub-parsec reprocessing media. Aim. We conduct numerical modeling of polarization reverberation and provide theoretical predictions for the polarization time lag induced by different AGN components. The model parameters are adjusted to the observational appearance of the Seyfert 1 galaxy NGC 4151. Methods: We modeled scattering-induced polarization and tested different geometries for the circumnuclear dust component. Our tests included the effects of clumpiness and different dust prescriptions. To further extend the model, we also explored the effects of additional ionized winds stretched along the polar direction, and of an equatorial scattering ring that is responsible for the polarization angle observed in pole-on AGN. The simulations were run using a time-dependent version of the STOKES code. Results: Our modeling confirms the previously found polarization characteristics as a function of the observer`s viewing angle. When the dust adopts a flared-disk geometry, the lags reveal a clear difference between type 1 and type 2 AGN. This distinction is less clear for a torus geometry where the time lag is more sensitive to the geometry and optical depth of the inner surface layers of the funnel. The presence of a scattering equatorial ring and ionized outflows increased the recorded polarization time lags, and the polar outflows smooths out dependence on viewing angle, especially for the higher optical depth of the

  9. Solid Polarized Targets and Applications

    International Nuclear Information System (INIS)

    Crabb, D. G.

    2008-01-01

    Examples are given of dynamically polarized targets in use today and how the subsystems have changed to meet the needs of todays experiments. Particular emphasis is placed on target materials such as ammonia and lithium deuteride. Recent polarization studies of irradiated materials such as butanol, deuterated butanol, polyethylene, and deuterated polyethylene are presented. The operation of two non-DNP target systems as well as applications of traditional DNP targets are briefly discussed

  10. Artificial anisotropy and polarizing filters.

    Science.gov (United States)

    Flory, François; Escoubas, Ludovic; Lazaridès, Basile

    2002-06-01

    The calculated spectral transmittance of a multilayer laser mirror is used to determine the effective index of the single layer equivalent to the multilayer stack. We measure the artificial anisotropy of photoresist thin films whose structure is a one-dimensional, subwavelength grating obtained from interference fringes. The limitation of the theory of the first-order effective index homogenization is discussed. We designed normal-incidence, polarizing coating and a polarization rotator by embedding anisotropic films in simple multilayer structures.

  11. Polarization bremsstrahlung in α decay

    International Nuclear Information System (INIS)

    Amusia, M. Ya.; Zon, B. A.; Kretinin, I. Yu.

    2007-01-01

    A mechanism of formation of electromagnetic radiation that accompanies α decay and is associated with the emission of photons by electrons of atomic shells due to the scattering of α particles by these atoms (polarization bremsstrahlung) is proposed. It is shown that, when the photon energy is no higher than the energy of K electrons of an atom, polarization bremsstrahlung makes a significant contribution to the bremsstrahlung in α decay

  12. Coherent states with elliptical polarization

    OpenAIRE

    Colavita, E.; Hacyan, S.

    2004-01-01

    Coherent states of the two dimensional harmonic oscillator are constructed as superpositions of energy and angular momentum eigenstates. It is shown that these states are Gaussian wave-packets moving along a classical trajectory, with a well defined elliptical polarization. They are coherent correlated states with respect to the usual cartesian position and momentum operators. A set of creation and annihilation operators is defined in polar coordinates, and it is shown that these same states ...

  13. Polarization of Coronal Forbidden Lines

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hao; Qu, Zhongquan [Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan 650011 (China); Landi Degl’Innocenti, Egidio, E-mail: sayahoro@ynao.ac.cn [Dipartimento di Astronomia e Scienza dello Spazio, Università di Firenze, Largo E. Fermi 2, I-50125 Firenze (Italy)

    2017-03-20

    Since the magnetic field is responsible for most manifestations of solar activity, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields, particularly in the outer atmosphere. To this end, it is important to develop rigorous diagnostic tools to interpret polarimetric observations in suitable spectral lines. This paper is devoted to analyzing the diagnostic content of linear polarization imaging observations in coronal forbidden lines. Although this technique is restricted to off-limb observations, it represents a significant tool to diagnose the magnetic field structure in the solar corona, where the magnetic field is intrinsically weak and still poorly known. We adopt the quantum theory of polarized line formation developed in the framework of the density matrix formalism, and synthesize images of the emergent linear polarization signal in coronal forbidden lines using potential-field source-surface magnetic field models. The influence of electronic collisions, active regions, and Thomson scattering on the linear polarization of coronal forbidden lines is also examined. It is found that active regions and Thomson scattering are capable of conspicuously influencing the orientation of the linear polarization. These effects have to be carefully taken into account to increase the accuracy of the field diagnostics. We also found that linear polarization observation in suitable lines can give valuable information on the long-term evolution of the magnetic field in the solar corona.

  14. Polarization in free electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Papadichev, V.A. [Lebedev Physical Institute, Moscow (Russian Federation)

    1995-12-31

    Polarization of electromagnetic radiation is required very often in numerous scientific and industrial applications: studying of crystals, molecules and intermolecular interaction high-temperature superconductivity, semiconductors and their transitions, polymers and liquid crystals. Using polarized radiation allows to obtain important data (otherwise inaccessible) in astrophysics, meteorology and oceanology. It is promising in chemistry and biology for selective influence on definite parts of molecules in chain synthesis reactions, precise control of various processes at cell and subcell levels, genetic engineering etc. Though polarization methods are well elaborated in optics, they can fail in far-infrared, vacuum-ultraviolet and X-ray regions because of lack of suitable non-absorbing materials and damaging of optical elements at high specific power levels. Therefore, it is of some interest to analyse polarization of untreated FEL radiation obtained with various types of undulators, with and without axial magnetic field. The polarization is studied using solutions for electron orbits in various cases: plane or helical undulator with or without axial magnetic field, two plane undulators, a combination of right- and left-handed helical undulators with equal periods, but different field amplitudes. Some examples of how a desired polarization (elliptical circular or linear) can be obtained or changed quickly, which is necessary in many experiments, are given.

  15. Add Value

    DEFF Research Database (Denmark)

    Kobbelgaard, Cecilie Elisabeth

    2016-01-01

    "Add Value – kend din kunde" er et brætspil, som giver både offentlige og private virksomheder unikke muligheder for at forbedre deres service overfor kunderne. Spillet giver, på en alternativ og handlingsorienteret måde, mulighed for at blive skarpere på kundeoplevelsen – hvor er der værdi...... at hente, og hvor kan der spares på tid og ressourcer? Dette samtidig med, at kunderne får den oplevelse og service, de forventer. Når I spiller "Add Value – kend din kunde" sættes der fokus på Jeres kundeservice ud fra kundens perspektiv, og det er i alle Jeres kontaktflader med kunden. Lige fra kunden...

  16. Conservation Value

    OpenAIRE

    Tisdell, Clement A.

    2010-01-01

    This paper outlines the significance of the concept of conservation value and discusses ways in which it is determined paying attention to views stemming from utilitarian ethics and from deontological ethics. The importance of user costs in relation to economic decisions about the conservation and use of natural resources is emphasised. Particular attention is given to competing views about the importance of conserving natural resources in order to achieve economic sustainability. This then l...

  17. Body water distribution in severe obesity and its assessment from eight-polar bioelectrical impedance analysis.

    Science.gov (United States)

    Sartorio, A; Malavolti, M; Agosti, F; Marinone, P G; Caiti, O; Battistini, N; Bedogni, G

    2005-02-01

    To measure body water distribution and to evaluate the accuracy of eight-polar bioelectrical impedance analysis (BIA) for the assessment of total body water (TBW) and extracellular water (ECW) in severe obesity. Cross-sectional study. Obesity clinic. In all, 75 women aged 18-66 y, 25 with body mass index (BMI) between 19.1 and 29.9 kg/m(2) (ie not obese), 25 with BMI between 30.0 and 39.9 kg/m(2) (ie class I and II obese), and 25 with BMI between 40.0 and 48.2 kg/m(2) (ie class III obese). TBW and ECW were measured by (2)H(2)O and Br dilution. Body resistance (R) was obtained by summing the resistances of arms, trunk and legs as measured by eight-polar BIA (InBody 3.0, Biospace, Seoul, Korea). The resistance index at a frequency of x kHz (RI(x)) was calculated as height (2)/R(x). ECW : TBW was similar in women with class III (46+/-3%, mean+/-s.d.) and class I-II obesity (45+/-3%) but higher than in nonobese women (39+/-3%, P<0.05). In a random subsample of 37 subjects, RI(500) explained 82% of TBW variance (P<0.0001) and cross-validation of the obtained algorithm in the remaining 38 subjects gave a percent root mean square error (RMSE%) of 5% and a pure error (PE) of 2.1 l. In the same subjects, RI(5) explained 87% of ECW variance (P<0.0001) and cross-validation of the obtained algorithm gave a RMSE% of 8% and a PE of 1.4 l. The contribution of weight and BMI to the prediction of TBW and ECW was nil or negligible on practical grounds. ECW : TBW is similar in women with class I-II and class III obesity up to BMI values of 48.2 kg/m(2). Eight-polar BIA offers accurate estimates of TBW and ECW in women with a wide range of BMI (19.1-48.2 kg/m(2)) without the need of population-specific formulae.

  18. Induced polarization imaging applied to exploration for low-sulfidation epithermal Au-Ag deposits, Seongsan mineralized district, South Korea

    Science.gov (United States)

    Han, Man-Ho; Shin, Seung Wook; Park, Samgyu; Cho, Seong-Jun; Kim, Jung-Ho

    2016-10-01

    The determination of mineralization boundaries during mineral exploration for undiscovered low-sulfidation epithermal Au-Ag deposits is a significant challenge because of the extensive survey areas required. Induced polarization (IP) imaging is an effective geophysical technique for the detection of sulfides or clay. Thus, this method is considered useful to determine the boundaries of subsurface mineralization and hydrothermal alteration associated with epithermal deposits. We used 2D and 3D IP imaging to define the silicification and mineralization boundaries of the Moisan deposit in the Seongsan mineralized district, which is geologically well-known. The boundaries of the silicification zone were defined by high resistivity values of 600 Ω-m, and those of the mineralization zone were defined by high global chargeability values of 3 mV V-1. The continuity of the high resistivity anomaly corresponded well to the silicification (quartz veins) exposed in outcrop. In addition, it is geologically reasonable that the chargeability anomaly, ⩾3 mV V-1, associated with the mineralization/hydrothermal alteration zone was concentrated at near-surface depths, and extensively surrounding the resistivity anomaly, ⩾600 Ω-m, associated with the silicification zone.

  19. Circular polarization in the optical afterglow of GRB 121024A.

    Science.gov (United States)

    Wiersema, K; Covino, S; Toma, K; van der Horst, A J; Varela, K; Min, M; Greiner, J; Starling, R L C; Tanvir, N R; Wijers, R A M J; Campana, S; Curran, P A; Fan, Y; Fynbo, J P U; Gorosabel, J; Gomboc, A; Götz, D; Hjorth, J; Jin, Z P; Kobayashi, S; Kouveliotou, C; Mundell, C; O'Brien, P T; Pian, E; Rowlinson, A; Russell, D M; Salvaterra, R; di Serego Alighieri, S; Tagliaferri, G; Vergani, S D; Elliott, J; Fariña, C; Hartoog, O E; Karjalainen, R; Klose, S; Knust, F; Levan, A J; Schady, P; Sudilovsky, V; Willingale, R

    2014-05-08

    Gamma-ray bursts (GRBs) are most probably powered by collimated relativistic outflows (jets) from accreting black holes at cosmological distances. Bright afterglows are produced when the outflow collides with the ambient medium. Afterglow polarization directly probes the magnetic properties of the jet when measured minutes after the burst, and it probes the geometric properties of the jet and the ambient medium when measured hours to days after the burst. High values of optical polarization detected minutes after the burst of GRB 120308A indicate the presence of large-scale ordered magnetic fields originating from the central engine (the power source of the GRB). Theoretical models predict low degrees of linear polarization and no circular polarization at late times, when the energy in the original ejecta is quickly transferred to the ambient medium and propagates farther into the medium as a blast wave. Here we report the detection of circularly polarized light in the afterglow of GRB 121024A, measured 0.15 days after the burst. We show that the circular polarization is intrinsic to the afterglow and unlikely to be produced by dust scattering or plasma propagation effects. A possible explanation is to invoke anisotropic (rather than the commonly assumed isotropic) electron pitch-angle distributions, and we suggest that new models are required to produce the complex microphysics of realistic shocks in relativistic jets.

  20. Superconducting polarizing magnet for a movable polarized target

    International Nuclear Information System (INIS)

    Anishchenko, N.G.; Bartenev, V.D.; Blinov, N.A.

    1998-01-01

    The superconducting polarizing magnet was constructed for the JINR (Dubna) movable polarized target (MPT) with working volume 200 mm long and 30 mm in diameter. The magnet provides a polarizing magnetic field up to 6 T in the centre with the uniformity of 4.5 x 10 -4 in the working volume of the target. The magnet contains a main solenoidal winding 558 mm long and 206/144 mm in diameters, and compensating and correcting winding placed at its ends. The windings are made of a NbTi wire, impregnated with the epoxy resin and placed in the horizontal cryostat. The diameter of the 'warm' aperture of the magnet cryostat is 96 mm. The design and technology of the magnet winding are described. Results of the magnetic field map measurements, using a NMR-magnetometer are given. A similar magnet constructed at DAPNIA, CEA/Saclay (France), represented a model for the present development. The MPT array is installed in the beam line of polarized neutrons produced by break-up of polarized deuterons extracted from the synchrophasotron of the Laboratory of High Energies (LHE), JINR (Dubna)

  1. Circular polarization of γ-quanta radiated in the capture of polarized neutrons by protons and the quark compound bag model

    International Nuclear Information System (INIS)

    Grach, I.L.; Shmatkov, M.Zh.

    1983-01-01

    The circular polarization Psub(γ) of γ-quanta radiated in the capture of polarized neutrons by protons is calculated The contribution of the M1 and E2 radiation of nucleons to Psub(γ) is found using the accurate wave functions of the continuous spectrum. The contribution of the six-quark bag to the polarization Psub(γ) is determined. The value of Psub(γ) is related to the admixture of the 6q-bag in the deuteron. Experimental value of Psub(γ) corresponds to small (< or approximately 0.7%) admixture of the bag

  2. Commissioning of the Delta Polarizing Undulator at LCLS

    Energy Technology Data Exchange (ETDEWEB)

    Nuhn, Heinz-Dieter

    2015-09-25

    The Linac Coherent Light Source (LCLS) generates linearly polarized, intense, high-brightness x-ray pulses from planar fixed-gap undulators. While the fixed-gap design supports a very successful and tightly controlled alignment concept, it provides only limited taper capability (up to 1% through canted pole and horizontal position adjustability) and lacks polarization control. The latter is of great importance for soft x-ray experiments. A new 3.2-m-long compact undulator (based on the Cornell University Delta design) has been developed and installed in place of the last LCLS undulator segment (U33) in October 2014. This undulator provides full control of the polarization degree and K value. Used on its own, it produces fully polarized radiation in the selected state (linear, circular or elliptical) but at low intensity. To increase the output power by orders of magnitude, the electron beam is micro-bunched by several (~10) of the upstream LCLS undulator segments operated in the linear FEL regime. As unavoidable by-product, this microbunching process produces moderate amounts of horizontally linear polarized radiation which mixes with the radiation produced by the Delta undulator. This unwanted radiation component has been greatly reduced by the reverse taper configuration, as suggested by E. Schneidmiller and M. Yurkov. Full elimination of the linear polarized component was achieved through spatial separation combined with transverse collimation. The paper describes these and other methods tested during commissioning. It also presents results of polarization measurements showing high degrees of circular polarization in the soft x-ray wavelength range (500 eV - 1500 eV).

  3. The effects of polarized light therapy in pressure ulcer healing

    Directory of Open Access Journals (Sweden)

    Đurović Aleksandar

    2008-01-01

    Full Text Available Background/Aim. Neglecting polarized light as an adjuvant therapy for pressure ulcers and methodology distinctions in the trials engaging polarized light are the reasons for many dilemmas and contradictions. The aim of this study was to establish the effects of polarized light therapy in pressure ulcer healing. Methods. This prospective randomized single-blind study involved 40 patients with stage I-III of pressure ulcer. The patients in the experimental group (E were subjected, besides polarized light therapy, to standard wound cleaning and dressing. Standard wound cleaning and dressing were the only treatment used in the control group (C. A polarized light source was a Bioptron lamp. Polarized light therapy was applied for six min daily, five times a week, four weeks. The Pressure Ulcer Scale for Healing (PUSH was used in the assessment of outcome. Statistic analysis included Mann Whitney Test, Fisher Exact Test, Wilcoxon Signed Rank test. Results. There were significant differences between the groups at the end of the treatment regarding the surface of pressure ulcer (E: 10.80±19.18; C: 22,97±25,47; p = 0.0005, rank of pressure ulcer (E: 5.90±2.48; C: 8.6±1.05; p = 0.0005 and total PUSH score (E: 7.35±3.17; C: 11.85±2.35; p = 0,0003. The patients in the experimental group had significantly better values of the parameters monitored than the patients in the control group. Conclusion. After a four-week polarized light therapy 20 patients with stage I-III ulcer had significant improvement in pressure ulcer healing, so it could be useful to apply polarized light in the treatment of pressure ulcers.

  4. The effects of polarized light therapy in pressure ulcer healing.

    Science.gov (United States)

    Durović, Aleksandar; Marić, Dragan; Brdareski, Zorica; Jevtić, Miodrag; Durdević, Slavisa

    2008-12-01

    Neglecting polarized light as an adjuvant therapy for pressure ulcers and methodology distinctions in the trials engaging polarized light are the reasons for many dilemmas and contradictions. The aim of this study was to establish the effects of polarized light therapy in pressure ulcer healing. This prospective randomized single-blind study involved 40 patients with stage I-III of pressure ulcer. The patients in the experimental group (E) were subjected, besides polarized light therapy, to standard wound cleaning and dressing. Standard wound cleaning and dressing were the only treatment used in the control group (C). A polarized light source was a Bioptron lamp. Polarized light therapy was applied for six min daily, five times a week, four weeks. The Pressure Ulcer Scale for Healing (PUSH) was used in the assessment of outcome. Statistic analysis included Mann Whitney Test, Fisher Exact Test, Wilcoxon Signed Rank test. There were significant differences between the groups at the end of the treatment regarding the surface of pressure ulcer (E: 10.80 +/- 19.18; C: 22,97 +/- 25,47; p = 0.0005), rank of pressure ulcer (E: 5.90 +/- 2.48; C: 8.6 +/- 1.05; p = 0.0005) and total PUSH score (E: 7.35 +/- 3.17; C: 11.85 +/- 2.35; p = 0,0003). The patients in the experimental group had significantly better values of the parameters monitored than the patients in the control group. After a four-week polarized light therapy 20 patients with stage I-III ulcer had significant improvement in pressure ulcer healing, so it could be useful to apply polarized light in the treatment of pressure ulcers.

  5. Polarization fluctuations in stationary light beams

    International Nuclear Information System (INIS)

    Shevchenko, A.; Setaelae, T.; Kaivola, M.; Friberg, A.T.; Royal Institute of Technology , Department of Microelectronics and Applied Physics; Sweden)

    2009-01-01

    For stationary beams the degree of polarization contains only limited information on time dependent polarization. Two approaches towards assessing a beams polarization dynamics, one based on Poincare and the other on Jones vector formalism, are described leading to the notion of polarization time. Specific examples of partially temporally coherent electromagnetic beams are discussed. (Author)

  6. FIRST POLARIZED PROTON COLLISIONS AT RHIC

    International Nuclear Information System (INIS)

    ROSER, T.; AHRENS, L.; ALESSI, J.; BAI, M.; BEEBE-WANG, J.; BRENNAN, J.M.; BROWN, K.A.; BUNCE, G.; CAMERON, P.; COURANT, E.D.; DREES, A.; FISCHER, W.; FLILLER, R. III; GLENN, W.; HUANG, H.; LUCCIO, A.U.; MACKAY, W.W.; MAKDISI, Y.; MONTAG, C.; PILAT, F.; PTITSYN, V.; SATOGATA, T.

    2002-01-01

    We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180 o about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV

  7. Apico-basal polarity complex and cancer

    Indian Academy of Sciences (India)

    Apico-basal polarity is a cardinal molecular feature of adult eukaryotic epithelial cells and appears to be involved in several key cellular processes including polarized cell migration and maintenance of tissue architecture. Epithelial cell polarity is maintained by three well-conserved polarity complexes, namely, PAR, Crumbs ...

  8. Inclusive quasielastic scattering of polarized electrons from polarized nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Amaro, J.E. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Center for Theoretical Physics]|[Universidad de Granada (Spain). Dept. de Fisica Moderna]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Lab. for Nuclear Science]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics; Caballero, J.A. [Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain). Inst. de Estructura de la Materia]|[Sevilla Univ. (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Donnelly, T.W. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Center for Theoretical Physics]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Lab. for Nuclear Science]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics; Moya de Guerra, E. [Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain). Inst. de Estructura de la Materia

    1996-12-23

    The inclusive quasielastic response functions that appear in the scattering of polarized electrons from polarized nuclei are computed and analyzed for several closed-shell-minus-one nuclei with special attention paid to {sup 39}K. Results are presented using two models for the ejected nucleon - when described by a distorted wave in the continuum shell model or by a plane wave in PWIA with on- and off-shell nucleons. Relativistic effects in kinematics and in the electromagnetic current have been incorporated throughout. Specifically, the recently obtained expansion of the electromagnetic current in powers only of the struck nucleon`s momentum is employed for the on-shell current and the effects of the first-order terms (spin-orbit and convection) are compared with the zeroth-order (charge and magnetization) contributions. The use of polarized inclusive quasielastic electron scattering as a tool for determining near-valence nucleon momentum distributions is discussed. (orig.).

  9. System of measurement of proton polarization in a polarized target

    Energy Technology Data Exchange (ETDEWEB)

    Karnaukov, I.M.; Chechetenko, V.F.; Lukhanin, A.A.; Telegin, Y.N.; Trotsenko, V.I.

    1985-05-01

    This paper describes a nuclear magnetic resonance spectrometer with high sensitivity. The signal of NMR absorption is recorded by a Q-meter with a series circuit and a circuit for compensation of the resonance characteristic of the measuring circuit. In order to ensure uniform sensitivity of the system to the state of polarization throughout the volume of the target and to enhance the S/N ration the measuring coil is made of a flat conductor. The polarization-measuring system works on-line with an M-6000 computer. The total error of measurement of the polarization of free protons in a target with allowance for the error due to local depolarization of free protons in a target with allowance for the error due to local depolarization of the working substance under irradiation with an intense photon beam is less than or equal to 6%.

  10. Electrical resistivities of rocks from Chalk River

    International Nuclear Information System (INIS)

    Katsube, T.J.; Hume, J.P.

    1989-01-01

    Bulk rock resistivity and bulk surface resistivity measurements have been obtained for 40 gneissic rock samples from Chalk River, Ontario. Though bulk rock resistivity is a function of pore structure, pore-fluid resistivity and pore-surface resistivity, the amount of data documented for pore-surface resistivity is small compared to that for pore structure and pore-fluid resistivity. This study indicates that pore-surface resistivity has a significant effect on bulk rock resistivity. It is important that this fact be considered when interpreting resistivity data obtained by geophysical methods. In addition, a group of mafic gneiss samples had pore-surface resistivity values that were much lower than those reported for clays, glass beads or petroleum reservoir rocks. This is thought to be due to metallic minerals lining the pore walls. Other rock samples collected from the same area showed pore-surface resistivity value similar to those reported in the literature

  11. The addition of Si to the Ti-35Nb alloy and its effect on the corrosion resistance, when applied to biomedical materials; Efeito da adicao de Si sobre a resistencia a corrosao da liga Ti-35Nb para aplicacoes biomedicas

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, A.M.G.; Souza, S.A.; Batista, W.W.; Macedo, M.C.S.S., E-mail: sasouza.sandra@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Ciencia e Engenharia de Materiais

    2014-07-01

    Alloy elements such as niobium and silicon have been added to titanium as an alternative for new materials to be used in orthopedic implants. However, these new materials' behavior, in face of corrosion is still demanding careful investigations because they will be subjected to an aggressive environ, such as the human body. This study, the corrosion resistance of the Ti-35Nb-(0; 0,15; 0,35; 0,55)Si (% in mass) when in physiological medium was assessed by means of polarization curves, open circuit potential and electrochemical impedance spectroscopy. The compositions of the passive films were analyzed by XPS. Outcomes show that the alloys presented good rapid repassivation capacity after film breaking under high potentials. The high values of resistance to polarization- Rp-pinpoint that the formed oxide films are resistive. They work as a protecting barrier against aggressive ions. Data suggest that the studied alloys are promising for orthopedic implant applications. (author)

  12. Protecting polar wilderness : Just a western philosophical idea or a useful concept for regulating human activities in the polar regions?

    NARCIS (Netherlands)

    Bastmeijer, Kees; Leary, D.; Koivurova, T.; Alfredsson, G.

    2009-01-01

    Governments involved in Arctic and Antarctic governance have been well aware of the increasing human pressure on the Polar Regions and particularly the last two decades many initiatives have been taken to protect the Arctic and Antarctic environment. But what values are to be protected? This paper

  13. Performance of the SLC polarized electron source with high polarization

    International Nuclear Information System (INIS)

    Clendenin, J.E.; Alley, R.K.; Aoyagi, H.

    1993-04-01

    For the 1992 operating cycle of the SLAC Linear Collider (SLC), the polarized electron source (PES) during its maiden run successfully met the pulse intensity and overall efficiency requirements of the SLC. However, the polarization of the bulk GaAs cathode was low (∼27%) and the pulse-to-pulse stability was marginal. We have shown that adequate charge for the SLC can be extracted from a strained layer cathode having P e ∼80% even though the quantum efficiency (QE) is - beam stability. The performance of the PES during the 1993 SLC operating cycle with these and other improvements is discussed

  14. PIPER: Primordial Inflation Polarization Explorer

    Science.gov (United States)

    Lazear, Justin; Benford, D.; Chuss, D.; Fixsen, D.; Hinderks, J.; Hinshaw, G.; Jhabvala, C.; Johnson, B.; Kogut, A.; Mirel, P.; Mosely, H.; Staguhn, J.; Wollack, E.; Weston, A.; Vlahacos, K.; Bennett, C.; Eimer, J.; Halpern, M.; Irwin, K.; Dotson, J.; Ade, P.; Tucker, C.

    2011-05-01

    The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne instrument to measure the polarization of the cosmic microwave background in search of the expected signature of primordial gravity waves excited during an inflationary epoch shortly after the Big Bang. PIPER consists of two co-aligned telescopes, one sensitive to the Q Stokes parameter and the other to U. Sky signals will be detected with 5120 transition edge sensor (TES) bolometers distributed in four rectangular close-packed arrays maintained at 100 mK. To maximize the sensitivity of the instrument, both telescopes are mounted within a single open bucket dewar and are maintained at 1.5 K throughout flight, with no ambient-temperature windows between the sky and the detectors. To mitigate the effects of systematic errors, the polarized sky signals will be modulated using a variable-delay polarization modulator. PIPER will observe at frequencies 200, 270, 350, and 600 GHz to separate the CMB from polarized dust emission within the Galaxy. A series of flights alternating between northern and southern hemisphere launch sites will produce nearly full-sky maps in Stokes I, Q, U, and V. I will discuss the current status and potential science returns from the PIPER project.

  15. Polar metals by geometric design

    Science.gov (United States)

    Kim, T. H.; Puggioni, D.; Yuan, Y.; Xie, L.; Zhou, H.; Campbell, N.; Ryan, P. J.; Choi, Y.; Kim, J.-W.; Patzner, J. R.; Ryu, S.; Podkaminer, J. P.; Irwin, J.; Ma, Y.; Fennie, C. J.; Rzchowski, M. S.; Pan, X. Q.; Gopalan, V.; Rondinelli, J. M.; Eom, C. B.

    2016-05-01

    Gauss’s law dictates that the net electric field inside a conductor in electrostatic equilibrium is zero by effective charge screening; free carriers within a metal eliminate internal dipoles that may arise owing to asymmetric charge distributions. Quantum physics supports this view, demonstrating that delocalized electrons make a static macroscopic polarization, an ill-defined quantity in metals—it is exceedingly unusual to find a polar metal that exhibits long-range ordered dipoles owing to cooperative atomic displacements aligned from dipolar interactions as in insulating phases. Here we describe the quantum mechanical design and experimental realization of room-temperature polar metals in thin-film ANiO3 perovskite nickelates using a strategy based on atomic-scale control of inversion-preserving (centric) displacements. We predict with ab initio calculations that cooperative polar A cation displacements are geometrically stabilized with a non-equilibrium amplitude and tilt pattern of the corner-connected NiO6 octahedra—the structural signatures of perovskites—owing to geometric constraints imposed by the underlying substrate. Heteroepitaxial thin-films grown on LaAlO3 (111) substrates fulfil the design principles. We achieve both a conducting polar monoclinic oxide that is inaccessible in compositionally identical films grown on (001) substrates, and observe a hidden, previously unreported, non-equilibrium structure in thin-film geometries. We expect that the geometric stabilization approach will provide novel avenues for realizing new multifunctional materials with unusual coexisting properties.

  16. Planck intermediate results. XX. Comparison of polarized thermal emission from Galactic dust with simulations of MHD turbulence

    DEFF Research Database (Denmark)

    Cardoso, J. F.; Delabrouille, J.; Ganga, K.

    2015-01-01

    Polarized emission observed by Planck HFI at 353 GHz towards a sample of nearby fields is presented, focusing on the statistics of polarization fractions p and angles ψ. The polarization fractions and column densities in these nearby fields are representative of the range of values obtained over...... the whole sky. We find that: (i) the largest polarization fractions are reached in the most diffuse fields; (ii) the maximum polarization fraction pmax decreases with column density NH in the more opaque fields with NH> 1021 cm-2; and (iii) the polarization fraction along a given line of sight is correlated...... of the maximum polarization fraction with column density in nearby molecular clouds is well reproduced in the simulations, indicating that it is essentially due to the turbulent structure of the magnetic field: an accumulation of variously polarized structures along the line of sight leads to such an anti...

  17. A study of proton polarization in ammonia (NH sub 3 ) under irradiation and annealing

    Energy Technology Data Exchange (ETDEWEB)

    Belyaev, A.A.; Get' man, V.A.; Dzyubak, A.P.; Karnaukhov, I.M.; Lukhanin, A.A.; Neffa, A.Yu.; Semisalov, I.L.; Sorokin, P.V.; Sporov, E.S.; Telegin, Yu.N.; Tolmachev, I.A.; Trotsenko, V.I. (Kharkov Institute of Physics and Technology, Ukrainian SSR, Academy of Sciences, 310108 Kharkov, USSR (UA))

    1989-05-05

    The proton polarization in irradiated NH{sub 3} has been measured as a function of the irradiation dose and annealing temperature. The analysis of the experimental data obtained shows that under low-temperature'' irradiation along with the NH{sup {minus}}{sub 2} the e{sub tr}-radical is likely to be formed which contributes to the polarization build-up and relaxation and influences the radiation damage resistance of the target.

  18. NMR dispersion measurement of dynamic nuclear polarization

    International Nuclear Information System (INIS)

    Davies, K.; Cox, S.F.J.

    1978-01-01

    The feasibility of monitoring dynamic nuclear polarization from the NMR dispersive susceptibility is examined. Two prototype instruments are tested in a polarized proton target using organic target material. The more promising employs a tunnel diode oscillator, inside the target cavity, and should provide a precise polarization measurement working at a frequency far enough from the main resonance for the disturbance of the measured polarization to be negligible. Other existing methods for measuring target polarization are briefly reviewed. (author)

  19. Polarization in electron and proton beams

    International Nuclear Information System (INIS)

    Buon, J.

    1986-03-01

    One first introduces the concept of polarization for spin 1/2 particle beams and discusses properties of spin kinetics in a stationary magnetic field. Then the acceleration of polarized protons in synchrotrons is studied with emphasis on depolarization when resonances are crossed and on the cures for reducing it. Finally, transverse polarization of electrons in storage rings is discussed as an equilibrium between polarizing and depolarizing effects of synchrotron radiation. Means for obtaining longitudinal polarization are also treated

  20. Polarization-tuned diode behaviour in multiferroic BiFeO3 thin films

    KAUST Repository

    Yao, Yingbang

    2012-12-28

    Asymmetric rectifying I-V behaviour of multiferroic BiFeO3 (BFO) thin films grown on transparent ITO-coated glass was quantitatively studied as a function of ferroelectric polarization. Different polarized states were established by unipolar or bipolar poling with various applied electric fields. The effects of polarization relaxation and fatigue on the currents were also investigated. We found that the conduction currents and the associated rectifications were controlled by the amplitude and direction of the polarization. We clearly observed the linear dependence of the current on the polarization. It is suggested that the space-charge-limited conduction and the charge injection at the Schottky interface between the film and the electrodes dominate the current. The electrically controlled rectifying behaviour observed in this study may be useful in nonvolatile resistance memory devices or tunable diodes. © 2013 IOP Publishing Ltd.

  1. Fair Value or Market Value?

    Directory of Open Access Journals (Sweden)

    Bogdan Cosmin Gomoi

    2014-12-01

    Full Text Available When taking into consideration the issue of defining the “fair value” concept, those less experimented in the area often fall in the “price trap”, which is considered as an equivalent of the fair value of financial structures. This valuation basis appears as a consequence of the trial to provide an “accurate image” by the financial statements and, also, as an opportunity for the premises offered by the activity continuing principle. The specialized literature generates ample controversies regarding the “fair value” concept and the “market value” concept. The paper aims to debate this issue, taking into account various opinions.

  2. Frequency dependent polarization in blazars

    International Nuclear Information System (INIS)

    Bjoernsson, C.I.

    1984-10-01

    It is argued that the intrinsic frequency dependent polarization in blazars finds its most straightforward explanations in terms of a single rather than a multicomponent sourcemodel. In order to reproduce the observations, under the assumption that the emission mechanism is optically thin synchrotron radiation, both a well ordered magnetic field and an electron distribution with a sharp break or cuttoff are necessary. Non-uniform pitch angle distribution and/or environments where synchrotron losses are important are both conducive to producing strong frequency dependent polarization. Reasons are put forth as to why such conditions ar expected to occur in blazars. Two specific models are discussed in detail and it is shown that they are both able to produce strong frequency dependent polarization, even when the spectral index changes by a small amount only. (orig.)

  3. Report of the polarization group

    International Nuclear Information System (INIS)

    Ford, W.; Kondo, K.; Martin, F.; Manning, G.; Miller, D.; Prescott, C.

    1975-01-01

    The use of longitudinal polarization in the reaction e + e - → μ + μ - was studied. Modifications of the magnetic insertion which could reduce synchrotron radiation by two or more were considered. In addition, a specific design is suggested which incorporates the optimized magnetic configuration; it is assumed that no particle detection is necessary near the interaction vertex and the synchrotron radiation is ''dumped'' up - and downstream. Also considered were vacuum chambers in which the synchrotron radiation is absorbed locally so that shielded regions are provided for detectors near the interaction vertex. A scheme for rotating the polarization outside the experiment areas is detailed; in this way the design of experiments is greatly simplified. Local intense ionization of residual gas in the interaction region due to synchrotron radiation at the insertion was studied. Finally, some general considerations in the production and measurement of beam polarization are summarized. 2 figures

  4. Uses of laser optical pumping to produce polarized ion beams

    International Nuclear Information System (INIS)

    Anderson, L.W.

    1983-01-01

    Laser optical pumping can be used to produce polarized alkali atom beams or polarized alkali vapor targets. Polarized alkali atom beams can be converted into polarized alkali ion beams, and polarized alkali vapor targets can be used to produce polarized H - or 3 He - ion beams. In this paper the authors discuss how the polarized alkali atom beams and polarized alkali vapor targets are used to produce polarized ion beams with emphasis on the production of polarized negative ion beams

  5. Polarization-Dependent Multi-Functional Metamaterial as Polarization Filter, Transparent Wall and Circular Polarizer using Ring-Cross Resonator

    Directory of Open Access Journals (Sweden)

    Z. Zhang

    2017-09-01

    Full Text Available We propose a polarization-dependent multi-functional metamaterial using ring-cross resonator. Based on the analysis of surface current distributions induced by different polarized incidence, we demonstrate that the proposed metamaterial serves as a polarization filter, a transparent wall and a circular polarizer under different polarization normal incidence. Additionally, parameter analyses on the control of resonance are discussed to complementally explain the physical origin. Simulated results show that the proposed metamaterial functions as a polarization filter eliminating the x-polarization wave at 10.1 GHz and y-polarization wave at 14.3 GHz, a transparent wall transmitting both x-polarized and y-polarized incident waves at 12.6 GHz, and a broadband circular polarizer converting the +45° polarized (-45° polarized incident wave to the left (right handed circularly polarized wave from 10.8 to 12.8 GHz, respectively. Measured results agree well with the simulation and validate the performance of the proposed multifunctional metamaterial.

  6. Robust reflective ghost imaging against different partially polarized thermal light

    Science.gov (United States)

    Li, Hong-Guo; Wang, Yan; Zhang, Rui-Xue; Zhang, De-Jian; Liu, Hong-Chao; Li, Zong-Guo; Xiong, Jun

    2018-03-01

    We theoretically study the influence of degree of polarization (DOP) of thermal light on the contrast-to-noise ratio (CNR) of the reflective ghost imaging (RGI), which is a novel and indirect imaging modality. An expression for the CNR of RGI with partially polarized thermal light is carefully derived, which suggests a weak dependence of CNR on the DOP, especially when the ratio of the object size to the speckle size of thermal light has a large value. Different from conventional imaging approaches, our work reveals that RGI is much more robust against the DOP of the light source, which thereby has advantages in practical applications, such as remote sensing.

  7. Spin-polarized photoemission from SiGe heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, A.; Bottegoni, F.; Isella, G.; Cecchi, S.; Chrastina, D.; Finazzi, M.; Ciccacci, F. [LNESS-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)

    2013-12-04

    We apply the principles of Optical Orientation to measure by Mott polarimetry the spin polarization of electrons photoemitted from different group-IV heterostructures. The maximum measured spin polarization, obtained from a Ge/Si{sub 0.31}Ge{sub 0.69} strained film, undoubtedly exceeds the maximum value of 50% attainable in bulk structures. The explanation we give for this result lies in the enhanced band orbital mixing between light hole and split-off valence bands as a consequence of the compressive strain experienced by the thin Ge layer.

  8. Moral opinion polarization and the erosion of trust

    DEFF Research Database (Denmark)

    Rapp, Carolin

    2016-01-01

    generalized trust, we focus on opinion polarization as another potential impact factor on trust. In more detail, we investigate the extent to which polarization over morally charged issues such as homsexuality, abortion and euthanasia affects individuals' likelihood to trust others. We hypothesize that moral...... issues have a natural tendency to divide societies' opinions into opposing poles and, thus, to challenge social cohesion in modern civil societies. Based on hierarchical analyses of the fifth wave of the World Values Survey (WVS) - comprising a sample of 39 countries - our results reveal that individuals...

  9. Retention of intermediate polarization states in ferroelectric materials enabling memories for multi-bit data storage

    Science.gov (United States)

    Zhao, Dong; Katsouras, Ilias; Asadi, Kamal; Groen, Wilhelm A.; Blom, Paul W. M.; de Leeuw, Dago M.

    2016-06-01

    A homogeneous ferroelectric single crystal exhibits only two remanent polarization states that are stable over time, whereas intermediate, or unsaturated, polarization states are thermodynamically instable. Commonly used ferroelectric materials however, are inhomogeneous polycrystalline thin films or ceramics. To investigate the stability of intermediate polarization states, formed upon incomplete, or partial, switching, we have systematically studied their retention in capacitors comprising two classic ferroelectric materials, viz. random copolymer of vinylidene fluoride with trifluoroethylene, P(VDF-TrFE), and Pb(Zr,Ti)O3. Each experiment started from a discharged and electrically depolarized ferroelectric capacitor. Voltage pulses were applied to set the given polarization states. The retention was measured as a function of time at various temperatures. The intermediate polarization states are stable over time, up to the Curie temperature. We argue that the remarkable stability originates from the coexistence of effectively independent domains, with different values of polarization and coercive field. A domain growth model is derived quantitatively describing deterministic switching between the intermediate polarization states. We show that by using well-defined voltage pulses, the polarization can be set to any arbitrary value, allowing arithmetic programming. The feasibility of arithmetic programming along with the inherent stability of intermediate polarization states makes ferroelectric materials ideal candidates for multibit data storage.

  10. Electrical tuning of the polarization state of light using graphene-integrated anisotropic metasurfaces

    Science.gov (United States)

    Dutta-Gupta, Shourya; Dabidian, Nima; Kholmanov, Iskandar; Belkin, Mikhail A.; Shvets, Gennady

    2017-03-01

    Plasmonic metasurfaces have been employed for moulding the flow of transmitted and reflected light, thereby enabling numerous applications that benefit from their ultra-thin sub-wavelength format. Their appeal is further enhanced by the incorporation of active electro-optic elements, paving the way for dynamic control of light's properties. In this paper, we realize a dynamic polarization state generator using a graphene-integrated anisotropic metasurface (GIAM) that converts the linear polarization of the incident light into an elliptical one. This is accomplished by using an anisotropic metasurface with two principal polarization axes, one of which possesses a Fano-type resonance. A gate-controlled single-layer graphene integrated with the metasurface was employed as an electro-optic element controlling the phase and intensity of light polarized along the resonant axis of the GIAM. When the incident light is polarized at an angle to the resonant axis of the metasurface, the ellipticity of the reflected light can be dynamically controlled by the application of a gate voltage. Thus accomplished dynamic polarization control is experimentally demonstrated and characterized by measuring the Stokes polarization parameters. Large changes of the ellipticity and the tilt angle of the polarization ellipse are observed. Our measurements show that the tilt angle can be changed from positive values through zero to negative values while keeping the ellipticity constant, potentially paving the way to rapid ellipsometry and other characterization techniques requiring fast polarization shifting. This article is part of the themed issue 'New horizons for nanophotonics'.

  11. Alpha prime effect on mechanical properties and corrosion resistance of UR 52N+ duplex stainless steel

    International Nuclear Information System (INIS)

    Fontes, Talita Filier

    2009-01-01

    Alpha prime phase leads to decreased corrosion resistance and mechanical properties losses of duplex stainless steels. In this work mechanical and electrochemical tests were performed in duplex stainless steel UR 52N+ aged at 475 degree C for various periods in order to determine the sensibility of these tests to alpha prime presence. Hardness tests showed a gradual increase in its values; on the other hand, impact tests revealed that the material aged for 12h losses about 80% of energy absorption capacity of the solution annealed sample. Notwithstanding cyclic polarization tests showed that significant changes are only noted for aging times greater than 96h. (author)

  12. Polarized electroluminescence from silicon nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Bagraev, Nikolay; Danilovsky, Eduard; Gets, Dmitry; Klyachkin, Leonid; Kudryavtsev, Andrey; Kuzmin, Roman; Malyarenko, Anna [Ioffe Physical-Technical Institute, 194021 St. Petersburg (Russian Federation); Mashkov, Vladimir [St. Petersburg State Polytechnical University, 195251 St. Petersburg (Russian Federation)

    2012-05-15

    We present the first findings of the circularly polarized electroluminescence (CPEL) from silicon nanostructures which are the p-type ultra-narrow silicon quantum well (Si-QW) confined by {delta}-barriers heavily doped with boron. The CPEL dependences on the forward current and lateral electric field show the circularly polarized light emission which appears to be caused by the exciton recombination through the negative-U dipole boron centers at the Si-QW-{delta}-barriers interface with the assistance of phosphorus donors. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. All-fiber polarization switch

    Science.gov (United States)

    Knape, Harald; Margulis, Walter

    2007-03-01

    We report an all-fiber polarization switch made out of silica-based microstructured fiber suitable for Q-switching all-fiber lasers. Nanosecond high-voltage pulses are used to heat and expand an internal electrode to cause λ/2-polarization rotation in less than 10 ns for 1.5 μm light. The 10 cm long component has an experimentally measured optical insertion loss of 0.2 dB and a 0-10 kHz repetition frequency capacity and has been durability tested for more than 109 pulses.

  14. The sensitivity of income polarization

    DEFF Research Database (Denmark)

    Hussain, Azhar

    2009-01-01

    This study looks at polarization and its components' sensitivity to assumptions about equivalence scales, income definition, ethical income distribution parameters, and the income accounting period. A representative sample of Danish individual incomes from 1984 to 2002 is utilised. Results show...... that polarization has increased over time, regardless of the applied measure, when the last part of the period is compared to the first part of the period; primary causes being increased inequality (alienation) and faster income growth among high incomes relative to those in the middle of the distribution...

  15. Valuing vaccination.

    Science.gov (United States)

    Bärnighausen, Till; Bloom, David E; Cafiero-Fonseca, Elizabeth T; O'Brien, Jennifer Carroll

    2014-08-26

    Vaccination has led to remarkable health gains over the last century. However, large coverage gaps remain, which will require significant financial resources and political will to address. In recent years, a compelling line of inquiry has established the economic benefits of health, at both the individual and aggregate levels. Most existing economic evaluations of particular health interventions fail to account for this new research, leading to potentially sizable undervaluation of those interventions. In line with this new research, we set forth a framework for conceptualizing the full benefits of vaccination, including avoided medical care costs, outcome-related productivity gains, behavior-related productivity gains, community health externalities, community economic externalities, and the value of risk reduction and pure health gains. We also review literature highlighting the magnitude of these sources of benefit for different vaccinations. Finally, we outline the steps that need to be taken to implement a broad-approach economic evaluation and discuss the implications of this work for research, policy, and resource allocation for vaccine development and delivery.

  16. Valuing vaccination

    Science.gov (United States)

    Bärnighausen, Till; Bloom, David E.; Cafiero-Fonseca, Elizabeth T.; O’Brien, Jennifer Carroll

    2014-01-01

    Vaccination has led to remarkable health gains over the last century. However, large coverage gaps remain, which will require significant financial resources and political will to address. In recent years, a compelling line of inquiry has established the economic benefits of health, at both the individual and aggregate levels. Most existing economic evaluations of particular health interventions fail to account for this new research, leading to potentially sizable undervaluation of those interventions. In line with this new research, we set forth a framework for conceptualizing the full benefits of vaccination, including avoided medical care costs, outcome-related productivity gains, behavior-related productivity gains, community health externalities, community economic externalities, and the value of risk reduction and pure health gains. We also review literature highlighting the magnitude of these sources of benefit for different vaccinations. Finally, we outline the steps that need to be taken to implement a broad-approach economic evaluation and discuss the implications of this work for research, policy, and resource allocation for vaccine development and delivery. PMID:25136129

  17. Graphics of polar figure; Graficado de figura polar

    Energy Technology Data Exchange (ETDEWEB)

    Macias B, L.R

    1991-11-15

    The objective of this work, is that starting from a data file coming from a spectra that has been softened, and of the one that have been generated its coordinates to project it in stereographic form, to create the corresponding polar figure making use of the Cyber computer of the ININ by means of the GRAPHOS package. This work only requires a Beta, Fi and Intensity (I) enter data file. It starts of the existence of a softened spectra of which have been generated already with these data, making use of some language that in this case was FORTRAN for the Cyber computer, a program is generated supported in the Graphos package that allows starting of a reading of the Beta, Fi, I file, to generate the points in a stereographic projection and that it culminates with the graph of the corresponding polar figure. The program will request the pertinent information that is wanted to capture in the polar figure just as: date, name of the enter file, indexes of the polar figure, number of levels, radio of the stereographic projection (cms.), crystalline system to which belongs the sample, name the neuter graph file by create and to add the own general data. (Author)

  18. Corrosion resistance of surface modified nickel titanium archwires.

    Science.gov (United States)

    Krishnan, Manu; Seema, Saraswathy; Kumar, A Vinod; Varthini, N Parvatha; Sukumaran, Kalathil; Pawar, Vasant R; Arora, Vimal

    2014-03-01

    To compare the corrosion behavior of commercially available surface modified nickel titanium (NiTi) arch wires with respect to a conventional NiTi and to evaluate its association with surface characteristics. Five types of surface modified arch wires and a conventional NiTi arch wire, all from different manufacturers, were evaluated for their corrosion resistance from breakdown potential in an anodic polarization scan in Ringer's solution. Surface characteristics were determined from scanning electron microscopy, atomic force microscopy, and energy dispersive analysis. One-way analysis of variance and post hoc Duncan's multiple range tests were used to evaluate statistical significance. Surface modified NiTi wires showed significant improvement in corrosion resistance and reduction in surface roughness values. Breakdown potentials increased in the order of group 6 (conventional; 204 mV) corrosion resistance and decreasing surface roughness. However, neither factor could maintain a direct, one-to-one relationship. It meant that the type and nature of coating material can effectively influence the anticorrosive features of NiTi wires, compared with its surface roughness values.

  19. Optimization of s-Polarization Sensitivity in Apertureless Near-Field Optical Microscopy

    Directory of Open Access Journals (Sweden)

    Yuika Saito

    2012-01-01

    Full Text Available It is a general belief in apertureless near-field microscopy that the so-called p-polarization configuration, where the incident light is polarized parallel to the axis of the probe, is advantageous to its counterpart, the s-polarization configuration, where the incident light is polarized perpendicular to the probe axis. While this is true for most samples under common near-field experimental conditions, there are samples which respond better to the s-polarization configuration due to their orientations. Indeed, there have been several reports that have discussed such samples. This leads us to an important requirement that the near-field experimental setup should be equipped with proper sensitivity for measurements with s-polarization configuration. This requires not only creation of effective s-polarized illumination at the near-field probe, but also proper enhancement of s-polarized light by the probe. In this paper, we have examined the s-polarization enhancement sensitivity of near-field probes by measuring and evaluating the near-field Rayleigh scattering images constructed by a variety of probes. We found that the s-polarization enhancement sensitivity strongly depends on the sharpness of the apex of near-field probes. We have discussed the efficient value of probe sharpness by considering a balance between the enhancement and the spatial resolution, both of which are essential requirements of apertureless near-field microscopy.

  20. Assessing resistance of stabilized corrosion resistant steels to intergranular corrosion

    International Nuclear Information System (INIS)

    Karas, A.; Cihal, V. Jr.; Vanek, V.; Herzan, J.; Protiva, K.; Cihal, V.

    1987-01-01

    Resistance to intergranular corrosion was determined for four types of titanium-stabilized steels from the coefficients of stabilization efficiency according to the degree the chemical composition was known. The ATA SUPER steel showed the highest resistance parameter value. The resistance of this type of steel of a specific composition, showing a relatively low value of mean nitrogen content was compared with steel of an optimized chemical composition and with low-carbon niobium stabilized, molybdenum modified steels. The comparison showed guarantees of a sufficient resistance of the steel to intergranular corrosion. The method of assessing the resistance to intergranular corrosion using the calculation of the minimum content of Cr', i.e., the effective chromium content, and the maximum effective carbon content C' giving the resistance parameter k seems to be prospective for practical use in the production of corrosion resistant steels. (author). 1 tab., 5 figs., 15 refs

  1. Evaluation of the nanotube intrinsic resistance across the tip-carbon nanotube-metal substrate junction by Atomic Force Microscopy.

    Science.gov (United States)

    Dominiczak, Maguy; Otubo, Larissa; Alamarguy, David; Houzé, Frédéric; Volz, Sebastian; Noël, Sophie; Bai, Jinbo

    2011-04-14

    Using an atomic force microscope (AFM) at a controlled contact force, we report the electrical signal response of multi-walled carbon nanotubes (MWCNTs) disposed on a golden thin film. In this investigation, we highlight first the theoretical calculation of the contact resistance between two types of conductive tips (metal-coated and doped diamond-coated), individual MWCNTs and golden substrate. We also propose a circuit analysis model to schematize the «tip-CNT-substrate» junction by means of a series-parallel resistance network. We estimate the contact resistance R of each contribution of the junction such as Rtip-CNT, RCNT-substrate and Rtip-substrate by using the Sharvin resistance model. Our final objective is thus to deduce the CNT intrinsic radial resistance taking into account the calculated electrical resistance values with the global resistance measured experimentally. An unwished electrochemical phenomenon at the tip apex has also been evidenced by performing measurements at different bias voltages with diamond tips. For negative tip-substrate bias, a systematic degradation in color and contrast of the electrical cartography occurs, consisting of an important and non-reversible increase of the measured resistance. This effect is attributed to the oxidation of some amorphous carbon areas scattered over the diamond layer covering the tip. For a direct polarization, the CNT and substrate surface can in turn be modified by an oxidation mechanism.

  2. Evaluation of the nanotube intrinsic resistance across the tip-carbon nanotube-metal substrate junction by Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Alamarguy David

    2011-01-01

    Full Text Available Abstract Using an atomic force microscope (AFM at a controlled contact force, we report the electrical signal response of multi-walled carbon nanotubes (MWCNTs disposed on a golden thin film. In this investigation, we highlight first the theoretical calculation of the contact resistance between two types of conductive tips (metal-coated and doped diamond-coated, individual MWCNTs and golden substrate. We also propose a circuit analysis model to schematize the «tip-CNT-substrate» junction by means of a series-parallel resistance network. We estimate the contact resistance R of each contribution of the junction such as R tip-CNT, R CNT-substrate and R tip-substrate by using the Sharvin resistance model. Our final objective is thus to deduce the CNT intrinsic radial resistance taking into account the calculated electrical resistance values with the global resistance measured experimentally. An unwished electrochemical phenomenon at the tip apex has also been evidenced by performing measurements at different bias voltages with diamond tips. For negative tip-substrate bias, a systematic degradation in color and contrast of the electrical cartography occurs, consisting of an important and non-reversible increase of the measured resistance. This effect is attributed to the oxidation of some amorphous carbon areas scattered over the diamond layer covering the tip. For a direct polarization, the CNT and substrate surface can in turn be modified by an oxidation mechanism.

  3. Polarized proton parameters for the 2015 PP-on-Au setup in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-08-25

    Values are given for RHIC circumference shifts due to snakes for various situations. Relevant parameters are tabulated for polarized protons (PP) in the booster and in AGS and RHIC for PP-on-Au stores.

  4. Polarized proton parameters for the 2015 PP-on-Aluminum setup in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-10-02

    Values are given for RHIC circumference shifts due to snakes for various situations. Relevant parameters are tabulated for polarized protons (PP) in the booster and in AGS and RHIC for PP-on-Aluminum stores.

  5. VIIRS/J1 polarization narrative

    Science.gov (United States)

    Waluschka, Eugene; McCorkel, Joel; McIntire, Jeff; Moyer, David; McAndrew, Brendan; Brown, Steven W.; Lykke, Keith R.; Young, James B.; Fest, Eric; Butler, James; Wang, Tung R.; Monroy, Eslim O.; Turpie, Kevin; Meister, Gerhard; Thome, Kurtis J.

    2015-09-01

    The polarization sensitivity of the Visible/NearIR (VISNIR) bands in the Joint Polar Satellite Sensor 1 (J1) Visible Infrared Imaging Radiometer Suite (VIIRS) instrument was measured using a broadband source. While polarization sensitivity for bands M5-M7, I1, and I2 was less than 2.5 %, the maximum polarization sensitivity for bands M1, M2, M3, and M4 was measured to be 6.4 %, 4.4 %, 3.1 %, and 4.3 %, respectively with a polarization characterization uncertainty of less than 0.38%. A detailed polarization model indicated that the large polarization sensitivity observed in the M1 to M4 bands is mainly due to the large polarization sensitivity introduced at the leading and trailing edges of the newly manufactured VISNIR bandpass focal plane filters installed in front of the VISNIR detectors. This was confirmed by polarization measurements of bands M1 and M4 bands using monochromatic light. Discussed are the activities leading up to and including the two polarization tests, some discussion of the polarization model and the model results, the role of the focal plane filters, the polarization testing of the Aft-Optics-Assembly, the testing of the polarizers at the National Aeronautics and Space Administration's (NASA) Goddard center and at the National Institute of Science and Technology (NIST) facility and the use of NIST's Traveling Spectral Irradiance and Radiance responsivity Calibrations using Uniform Sources (T-SIRCUS) for polarization testing and associated analyses and results.

  6. VIIRS-J1 Polarization Narrative

    Science.gov (United States)

    Waluschka, Eugene; McCorkel, Joel; McIntire, Jeff; Moyer, David; McAndrew, Brendan; Brown, Steven W.; Lykke, Keith; Butler, James; Meister, Gerhard; Thome, Kurtis J.

    2015-01-01

    The VIS/NIR bands polarization sensitivity of Joint Polar Satellite Sensor 1 (JPSS1) Visible/Infrared Imaging Radiometer Suite (VIIRS) instrument was measured using a broadband source. While polarization sensitivity for bands M5-M7, I1, and I2 was less than 2.5%, the maximum polarization sensitivity for bands M1, M2, M3, and M4 was measured to be 6.4%, 4.4%, 3.1%, and 4.3%, respectively with a polarization characterization uncertainty of less than 0.3%. A detailed polarization model indicated that the large polarization sensitivity observed in the M1 to M4 bands was mainly due to the large polarization sensitivity introduced at the leading and trailing edges of the newly manufactured VISNIR bandpass focal plane filters installed in front of the VISNIR detectors. This was confirmed by polarization measurements of bands M1 and M4 bands using monochromatic light. Discussed are the activities leading up to and including the instruments two polarization tests, some discussion of the polarization model and the model results, the role of the focal plane filters, the polarization testing of the Aft-Optics-Assembly, the testing of the polarizers at Goddard and NIST and the use of NIST's T-SIRCUS for polarization testing and associated analyses and results.

  7. Influences of surface and flexoelectric polarization on the effective anchoring energy in nematic liquid crystal

    International Nuclear Information System (INIS)

    Guan Rong-Hua; Ye Wen-Jiang; Xing Hong-Yu

    2015-01-01

    The physical effects on surface and flexoelectric polarization in a weak anchoring nematic liquid crystal cell are investigated systematically. We derive the analytic expressions of two effective anchoring energies for lower and upper substrates respectively as well as their effective anchoring strengths and corresponding tilt angles of effective easy direction. All of these quantities are relevant to the magnitudes of both two polarizations and the applied voltage U. Based on these expressions, the variations of effective anchoring strength and the tilt angle with the applied voltage are calculated for the fixed values of two polarizations. For an original weak anchoring hybrid aligned nematic cell, it may be equivalent to a planar cell for a small value of U and has a threshold voltage. The variation of reduced threshold voltage with reduced surface polarization strength is also calculated. The role of surface polarization is important without the adsorptive ions considered. (paper)

  8. Polarization dependent switching of asymmetric nanorings with a circular field

    Directory of Open Access Journals (Sweden)

    Nihar R. Pradhan

    2016-01-01

    Full Text Available We experimentally investigated the switching from onion to vortex states in asymmetric cobalt nanorings by an applied circular field. An in-plane field is applied along the symmetric or asymmetric axis of the ring to establish domain walls (DWs with symmetric or asymmetric polarization. A circular field is then applied to switch from the onion state to the vortex state, moving the DWs in the process. The asymmetry of the ring leads to different switching fields depending on the location of the DWs and direction of applied field. For polarization along the asymmetric axis, the field required to move the DWs to the narrow side of the ring is smaller than the field required to move the DWs to the larger side of the ring. For polarization along the symmetric axis, establishing one DW in the narrow side and one on the wide side, the field required to switch to the vortex state is an intermediate value.

  9. Moral opinion polarization and the erosion of trust.

    Science.gov (United States)

    Rapp, Carolin

    2016-07-01

    Since Puntam's seminal work on declining levels of social capital, the question of how social trust is formed has reached unprecedented heights of critical enquiry. While most of the current research concentrates on ethnic diversity and income inequality as the main influences driving down generalized trust, we focus on opinion polarization as another potential impact factor on trust. In more detail, we investigate the extent to which polarization over morally charged issues such as homsexuality, abortion and euthanasia affects individuals' likelihood to trust others. We hypothesize that moral issues have a natural tendency to divide societies' opinions into opposing poles and, thus, to challenge social cohesion in modern civil societies. Based on hierarchical analyses of the fifth wave of the World Values Survey (WVS) - comprising a sample of 39 countries - our results reveal that individuals living in countries characterized by more opinion polarization tend to have less trust in other people. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Measurement of inclusive quasielastic scattering of polarized electrons from polarized 3He

    International Nuclear Information System (INIS)

    Woodward, C.E.; Beise, E.J.; Belz, J.E.; Carr, R.W.; Filippone, B.W.; Lorenzon, W.B.; McKeown, R.D.; Mueller, B.; O'Neill, T.G.; Dodson, G.; Dow, K.; Farkhondeh, M.; Kowalski, S.; Lee, K.; Makins, N.; Milner, R.; Thompson, A.; Tieger, D.; van den Brand, J.; Young, A.; Yu, X.; Zumbro, J.

    1990-01-01

    We report a measurement of the asymmetry in spin-dependent quasielastic scattering of longitudinally polarized electrons from a polarized 3 He gas target. This measurement represents the first demonstration of a new method for studying electromagnetic nuclear structure: the scattering of polarized electrons from a polarized nuclear target. The measured asymmetry is in good agreement with a Faddeev calculation and supports the picture of spin-dependent quasielastic scattering from polarized 3 He as predominantly scattering from a polarized neutron

  11. Planck intermediate results. XXI. Comparison of polarized thermal emission from Galactic dust at 353 GHz with interstellar polarization in the visible

    DEFF Research Database (Denmark)

    Cardoso, J.F.; Delabrouille, J.; Ganga, K.

    2015-01-01

    ) in the visible with that in the submillimetre. For those lines of sight through the diffuse interstellar medium with comparable values of the estimated column density and polarization directions close to orthogonal, we correlate properties in the submillimetre and visible to find two ratios, RS/V = (PS......The Planck survey provides unprecedented full-sky coverage of the submillimetre polarized emission from Galactic dust. In addition to the information on the direction of the Galactic magnetic field, this also brings new constraints on the properties of dust. The dust grains that emit the radiation...... seen by Planck in the submillimetre also extinguish and polarize starlight in the visible. Comparison of the polarization of the emission and of the interstellar polarization on selected lines of sight probed by stars provides unique new diagnostics of the emission and light scattering properties...

  12. Lunar Polar Landing Sites

    Science.gov (United States)

    Kamps, Oscar; Foing, Bernard H.; Flahaut, Jessica

    2016-07-01

    An important step for a scientific mission is to assess on where the mission should be conducted. This study on landing site selection focuses on a mission to the poles of the Moon where an in-situ mission should be conducted to answer the questions with respect to volatiles and ices. The European interest for a mission to the poles of the Moon is presented in the mission concept called Heracles. This mission would be a tele-operated, sample return mission where astronauts will controlling a rover from an Orion capsule in cislunar orbit. The primary selection of landing sites was based on the scientific interest of areas near the poles. The maximum temperature map from Diviner was used to select sites where CO^2¬ should always be stable. This means that the maximum temperature is lower than 54K which is the sublimation temperature for CO^2¬ in lunar atmospheric pressure. Around these areas 14 potential regions of interest were selected. Further selection was based on the epoch of the surface in these regions of interest. It was thought that it would be of high scientific value if sites are sampled which have another epoch than already sampled by one of the Apollo or Luna missions. Only 6 sites on both North as South Pole could contain stable CO^2 ¬and were older than (Pre-)Necterian. Before a landing site and rover traverse was planned these six sites were compared on their accessibility of the areas which could contain stable CO^2. It was assumed that slope lower than 20^o is doable to rove. Eventually Amundsen and Rozhdestvenskiy West were selected as regions of interest. Assumptions for selecting landing sites was that area should have a slope lower than 5^o, a diameter of 1km, in partial illuminated area, and should not be isolated but inside an area which is in previous steps marked as accessible area to rove. By using multiple tools in ArcGIS it is possible to present the area's which were marked as potential landing sites. The closest potential landing

  13. Hyperon polarization: theory and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Magnin, J.; Simao, F.R.A.

    1996-01-01

    We give a brief review of the experimental situation concerning hyperon polarization. We mention also the current models developed to understand the experimental results and make some comments on some theoretical aspects contained in the Thomas precession model. (author). 8 ref.

  14. Tau physics with polarized beams

    Energy Technology Data Exchange (ETDEWEB)

    Daoudi, M.

    1995-11-01

    We present the first results on tau physics using polarized beams. These include measurements of the {tau} Michel parameters {xi} and {xi}{delta} and the {tau} neutrino helicity h{sub {nu}}. The measurements were performed using the SLD detector at the Stanford Linear Collider (SLC).

  15. Circular polarization observed in bioluminescence

    NARCIS (Netherlands)

    Wijnberg, Hans; Meijer, E.W.; Hummelen, J.C.; Dekkers, H.P.J.M.; Schippers, P.H.; Carlson, A.D.

    1980-01-01

    While investigating circular polarization in luminescence, and having found it in chemiluminescence, we have studied bioluminescence because it is such a widespread and dramatic natural phenomenon. We report here that left and right lanterns of live larvae of the fireflies, Photuris lucicrescens and

  16. Verum focus and polar questions

    Directory of Open Access Journals (Sweden)

    Ion Giurgea

    2012-11-01

    Full Text Available We argue that some word order phenomena in Romanian and Sardinian are the result of a checking operation in the left periphery involving verum focus (i.e. focus on the polarity component of the sentence. In particular, this operation accounts for some word order patterns found in polar questions. In Romanian, polarity fronting is realized as head-movement of (V+T to a higher peripheral head which bears a Focus-probe. This licenses VS orders for predications in which VS is not allowed as a neutral order (i-level predicates, iteratives, generics. In Sardinian, an entire phrase headed by the lexical predicate (verbal non-finite form or non-verbal predicate is fronted before the auxiliary. We argue that this order is obtained by two movement operations, head-raising of Aux to Foc and movement of the predicate phrase to SpecFoc. We also present the semantics of polarity focus, distinguishing several types of focus (informational, emphatic, contrastive.

  17. Free radicals and polarized targets

    Science.gov (United States)

    Bunyatova, E. I.

    2004-06-01

    Many free radicals were added to organic compounds in search of high proton and deuteron polarizations. Few found practical application. A short review is presented, and special attention is given to some stable nitroxyl radicals which have lately been admixed to organic compounds solid at room temperature, in particular to scintillators.

  18. Free radicals and polarized targets

    Energy Technology Data Exchange (ETDEWEB)

    Bunyatova, E.I. E-mail: bunyatel@nusun.jinr.ru

    2004-06-21

    Many free radicals were added to organic compounds in search of high proton and deuteron polarizations. Few found practical application. A short review is presented, and special attention is given to some stable nitroxyl radicals which have lately been admixed to organic compounds solid at room temperature, in particular to scintillators.

  19. History of the polarized beam

    Energy Technology Data Exchange (ETDEWEB)

    Parker, E F

    1979-01-01

    In 1973, the first high energy polarized proton beam was developed at the Argonne Zero Gradient Synchrotron (ZGS). It operated very successfully and productively until 1979 when the ZGS was shut down permanently. This report describes the development, characteristics, and operations of this facility.

  20. TREC Dynamic Domain: Polar Science

    Science.gov (United States)

    2015-11-20

    similarity. However, not all teams that submitted web crawls to this dataset applied their jaccard- similarity algorithms . 4.2 Data Format ...analysis. These algorithms were focused then on allowing better answers to the below representative science queries of our Polar data: 1. What...

  1. Bacteriophage in polar inland waters

    Science.gov (United States)

    Säwström, Christin; Lisle, John; Anesio, A.M.; Priscu, John C.; Laybourn-Parry, J.

    2008-01-01

    Bacteriophages are found wherever microbial life is present and play a significant role in aquatic ecosystems. They mediate microbial abundance, production, respiration, diversity, genetic transfer, nutrient cycling and particle size distribution. Most studies of bacteriophage ecology have been undertaken at temperate latitudes. Data on bacteriophages in polar inland waters are scant but the indications are that they play an active and dynamic role in these microbially dominated polar ecosystems. This review summarises what is presently known about polar inland bacteriophages, ranging from subglacial Antarctic lakes to glacial ecosystems in the Arctic. The review examines interactions between bacteriophages and their hosts and the abiotic and biotic variables that influence these interactions in polar inland waters. In addition, we consider the proportion of the bacteria in Arctic and Antarctic lake and glacial waters that are lysogenic and visibly infected with viruses. We assess the relevance of bacteriophages in the microbial loop in the extreme environments of Antarctic and Arctic inland waters with an emphasis on carbon cycling.

  2. High current polarized proton sources

    Energy Technology Data Exchange (ETDEWEB)

    Alessi, J.G.

    1988-01-01

    Polarized proton sources are now being used more frequently on linacs. In pulsed operation up to 10 mA of /rvec H//sup +/ and 0.4 mA of /rvec H//sup /minus// have been produced. The present status of these sources, and developments to reach even higher intensities, are reviewed. 39 refs., 1 tab.

  3. the effect of surface polarity

    Indian Academy of Sciences (India)

    Abstract. An implant material when comes in contact with blood fluids (e.g., blood and lymph), adsorb proteins spontaneously on its surface. Notably, blood coagulation is influenced by many factors, including mainly chemical structure and polarity (charge) of the material. The present study describes the methodology to ...

  4. Verum focus and polar questions

    Directory of Open Access Journals (Sweden)

    Ion Giurgea

    2012-01-01

    Full Text Available We argue that some word order phenomena in Romanian and Sardinian are the result of a checkingoperation in the left periphery involving verum focus (i.e. focus on the polarity component of the sentence.In particular, this operation accounts for some word order patterns found in polar questions. In Romanian,polarity fronting is realized as head-movement of (V+T to a higher peripheral head which bears a Focusprobe.This licenses VS orders for predications in which VS is not allowed as a neutral order (i-levelpredicates, iteratives, generics. In Sardinian, an entire phrase headed by the lexical predicate (verbal nonfiniteform or non-verbal predicate is fronted before the auxiliary. We argue that this order is obtained bytwo movement operations, head-raising of Aux to Foc and movement of the predicate phrase to SpecFoc. Wealso present the semantics of polarity focus, distinguishing several types of focus (informational, emphatic,contrastive.

  5. The SLC polarized electron source

    International Nuclear Information System (INIS)

    Clendenin, J.E.

    1990-10-01

    A polarized electron source consisting of a 3-electrode photocathode gun and a flashlamp-pumped dye laser has been designed and built for the SLC and is currently undergoing commissioning. The source is described, and the operating configuration is discussed. The present status of the source and future plans are briefly indicated. 7 refs., 4 figs

  6. Polar heating in Saturn's thermosphere

    Directory of Open Access Journals (Sweden)

    C. G. A. Smith

    2005-10-01

    Full Text Available A 3-D numerical global circulation model of the Kronian thermosphere has been used to investigate the influence of polar heating. The distributions of temperature and winds resulting from a general heat source in the polar regions are described. We show that both the total energy input and its vertical distribution are important to the resulting thermal structure. We find that the form of the topside heating profile is particularly important in determining exospheric temperatures. We compare our results to exospheric temperatures from Voyager occultation measurements (Smith et al., 1983; Festou and Atreya, 1982 and auroral H3+ temperatures from ground-based spectroscopic observations (e.g. Miller et al., 2000. We find that a polar heat source is consistent with both the Smith et al. determination of T∞~400 K at ~30° N and auroral temperatures. The required heat source is also consistent with recent estimates of the Joule heating rate at Saturn (Cowley et al., 2004. However, our results show that a polar heat source can probably not explain the Festou and Atreya determination of T∞~800 K at ~4° N and the auroral temperatures simultaneously. Keywords. Ionosphere (Planetary ionosphere – Magnetospherica physics (Planetary magnetospheres – Meterology and atmospheric dynamics (Thermospheric dynamics

  7. Chemical Observations of a Polar Vortex Intrusion

    Science.gov (United States)

    Schoeberl, M. R.; Kawa, S. R.; Douglass, A. R.; McGee, T. J.; Browell, E.; Waters, J.; Livesey, N.; Read, W.; Froidevaux, L.

    2006-01-01

    An intrusion of vortex edge air in D the interior of the Arctic polar vortex was observed on the January 31,2005 flight of the NASA DC-8 aircraft. This intrusion was identified as anomalously high values of ozone by the AROTAL and DIAL lidars. Our analysis shows that this intrusion formed when a blocking feature near Iceland collapsed, allowing edge air to sweep into the vortex interior. along the DC-8 flight track also shows the intrusion in both ozone and HNO3. Polar Stratospheric Clouds (PSCs) were observed by the DIAL lidar on the DC-8. The spatial variability of the PSCs can be explained using MLS HNO3 and H2O observations and meteorological analysis temperatures. We also estimate vortex denitrification using the relationship between N2O and HNO3. Reverse domain fill back trajectory calculations are used to focus on the features in the MLS data. The trajectory results improve the agreement between lidar measured ozone and MLS ozone and also improve the agreement between the HNO3 measurements PSC locations. The back trajectory calculations allow us to compute the local denitrification rate and reduction of HCl within the filament. We estimate a denitrification rate of about lO%/day after exposure to below PSC formation temperature. Analysis of Aura MLS observations made

  8. Polarity Checks in Sectors 23 & 78

    CERN Document Server

    Calaga, R; Lamont, M; Ponce, L; Sun, Y; Tomás, R; Venturini-Delsolaro, W; Zimmermann, F

    2009-01-01

    During the first three LHC synchronization tests on August 10, August 24, and September 7, 2008, linear and higher-order polarity checks were performed with beam 1 in Sector 23 and beam 2 in Sector 78. The main principle of these checks was to launch free betatron oscillations and use the difference trajectory measurements with respect to inverted polarities of circuits under investigation. In the case of zero nominal strength for a circuit, a finite value was introduced. The magnet circuits subjected to these tests were the QT and QTL trim quadrupoles, the MQS skew quadrupoles, the SF and SD arc sextupole circuits, the MCS b3 spool pieces, the OD and OF Landau octupoles, and the MSS skew sextupoles. For some of these circuits sensitivity was enhanced by introducing large momentum offsets. To detect and remove improve spurious contributions from initially off-center orbits, four sets of trajectories were recorded, namely with and without oscillation, and with two magnet strength settings, respectively. We rep...

  9. Continuum treatment of electronic polarization effect.

    Science.gov (United States)

    Tan, Yu-Hong; Luo, Ray

    2007-03-07

    A continuum treatment of electronic polarization has been explored for in molecular mechanics simulations in implicit solvents. The dielectric constant for molecule interior is the only parameter in the continuum polarizable model. A value of 4 is found to yield optimal agreement with high-level ab initio quantum mechanical calculations for the tested molecular systems. Interestingly, its performance is not sensitive to the definition of molecular volume, in which the continuum electronic polarization is defined. In this model, quantum mechanical electrostatic field in different dielectric environments from vacuum, low-dielectric organic solvent, and water can be used simultaneously in atomic charge fitting to achieve consistent treatment of electrostatic interactions. The tests show that a single set of atomic charges can be used consistently in different dielectric environments and different molecular conformations, and the atomic charges transfer well from training monomers to tested dimers. The preliminary study gives us the hope of developing a continuum polarizable force field for more consistent simulations of proteins and nucleic acids in implicit solvents.

  10. Continuum treatment of electronic polarization effect

    Science.gov (United States)

    Tan, Yu-Hong; Luo, Ray

    2007-03-01

    A continuum treatment of electronic polarization has been explored for in molecular mechanics simulations in implicit solvents. The dielectric constant for molecule interior is the only parameter in the continuum polarizable model. A value of 4 is found to yield optimal agreement with high-level ab initio quantum mechanical calculations for the tested molecular systems. Interestingly, its performance is not sensitive to the definition of molecular volume, in which the continuum electronic polarization is defined. In this model, quantum mechanical electrostatic field in different dielectric environments from vacuum, low-dielectric organic solvent, and water can be used simultaneously in atomic charge fitting to achieve consistent treatment of electrostatic interactions. The tests show that a single set of atomic charges can be used consistently in different dielectric environments and different molecular conformations, and the atomic charges transfer well from training monomers to tested dimers. The preliminary study gives us the hope of developing a continuum polarizable force field for more consistent simulations of proteins and nucleic acids in implicit solvents.

  11. Polarized 3He gas circulating technologies for neutron analyzers

    Energy Technology Data Exchange (ETDEWEB)

    Watt, David W. [Xemed, LLC, Durham, NH (United States)

    2017-10-02

    with asymptotic to 45 percent, which was below expectations. This low value resulted from a stationary thermal inversion in the cell that caused most of the laser power to be absorbed near the laser inlet window and deprived the lower portions of the cell of pumping laser light. Possible solutions to this problem include enhanced cooling of the cell near the laser entry and slight detuning of the laser. 6. Ongoing work. Our polarizer development efforts are ongoing to pursue our interest in neutron analyzers, nuclear targets, and providing helium for medical imaging. Current tests in the pipeline include: 1. Testing cooling enhancements to improve laser penetration of spectrally narrow lasers; 2. Testing of a cell with isolation valves that minimizes diffusive contact with gas handling hardware during polarization; 3. Testing of smaller hybrid cells with reduced alkali loading; 4. Producing polarized helium-3 for MRI imaging at the University of Missouri.

  12. The State and Future of Mars Polar Science and Exploration

    Science.gov (United States)

    Clifford, Stephen M.; Crisp, David; Fisher, David A.; Herkenhoff, Ken E.; Smrekar, Suzanne E.; Thomas, Peter C.; Wynn-Williams, David D.; Zurek, Richard W.; Barnes, Jeffrey R.; Bills, Bruce G.

    2000-01-01

    As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of approx. 10(exp 6)sq km and total as much as 3-4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to he comparatively young-preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust over the past approx. 10(exp 5)-10(exp 8) years. For this reason, the martian polar deposits may serve as a Rosetta Stone for understanding the geologic and climatic history of the planet-documenting variations in insolation (due to quasiperiodic oscillations in the planet's obliquity and orbital elements), volatile mass balance, atmospheric composition, dust storm activity, volcanic eruptions, large impacts, catastrophic floods, solar luminosity, supernovae, and perhaps even a record of microbial life. Beyond their scientific value, the polar regions may soon prove important for another reason-providing a valuable and accessible reservoir of water to support the long-term human exploration of Mars. In this paper we assess the current state of Mars polar research, identify the key questions that motivate the exploration of the polar regions, discuss the extent to which current missions will address these questions, and speculate about what additional capabilities and investigations may be required to address the issues that remain outstanding.

  13. Local field in LiD polarized target material

    CERN Document Server

    Kisselev, Yu V; Baum, G; Berglund, P; Doshita, N; Gautheron, F; Görtz, S; Horikawa, N; Koivuniemi, J H; Kondo, K; Magnon, A; Meyer, Werner T; Reicherz, G

    2004-01-01

    We have experimentally studied the first and the second moments of D, **6Li and **7Li (I greater than 1/2) NMR lines in a granulated LiD- target material as a function of nuclear polarizations and the data has been compared with a theory elaborated by Abragam, Roinel and Bouffard for monocrystalline samples. The experiments were carried out in the large COMPASS twin-target at CERN. The static local magnetic field of the polarized nuclei was measured by frequency shift between the NMR-signals in the two oppositely polarized cells and lead to the first moment, whereas the investigation of the second moment was done through Gaussian approximation. The average field magnitude in granulated material was estimated 20% larger than the value given by the calculations for monocrystalline samples of cylindrical shape. The second moment shows a qualitative agreement with the theory but it is slightly larger at the negative than at the positive polarization. In a polarized mode, the moments depend on the saturated microw...

  14. The State and Future of Mars Polar Science and Exploration

    Science.gov (United States)

    Clifford, S.M.; Crisp, D.; Fisher, D.A.; Herkenhoff, K. E.; Smrekar, S.E.; Thomas, P.C.; Wynn-Williams, D. D.; Zurek, R.W.; Barnes, J.R.; Bills, B.G.; Blake, E.W.; Calvin, W.M.; Cameron, J.M.; Carr, M.H.; Christensen, P.R.; Clark, B. C.; Clow, G.D.; Cutts, J.A.; Dahl-Jensen, D.; Durham, W.B.; Fanale, F.P.; Farmer, J.D.; Forget, F.; Gotto-Azuma, K.; Grard, R.; Haberle, R.M.; Harrison, W.; Harvey, R.; Howard, A.D.; Ingersoll, A.P.; James, P.B.; Kargel, J.S.; Kieffer, H.H.; Larsen, J.; Lepper, K.; Malin, M.C.; McCleese, D.J.; Murray, B.; Nye, J.F.; Paige, D.A.; Platt, S.R.; Plaut, J.J.; Reeh, N.; Rice, J.W.; Smith, D.E.; Stoker, C.R.; Tanaka, K.L.; Mosley-Thompson, E.; Thorsteinsson, T.; Wood, S.E.; Zent, A.; Zuber, M.T.; Zwally, H.J.

    2000-01-01

    As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ???106 km2 and total as much as 3-4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young - preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust over the past ???105-108 years. For this reason, the martian polar deposits may serve as a Rosetta Stone for understanding the geologic and climatic history of the planet - documenting variations in insolation (due to quasiperiodic oscillations in the planet's obliquity and orbital elements), volatile mass balance, atmospheric composition, dust storm activity, volcanic eruptions, large impacts, catastrophic floods, solar luminosity, supernovae, and perhaps even a record of microbial life. Beyond their scientific value, the polar regions may soon prove important for another reason - providing a valuable and accessible reservoir of water to support the long-term human exploration of Mars. In this paper we assess the current state of Mars polar research, identify the key questions that motivate the exploration of the polar regions, discuss the extent to which current missions will address these questions, and speculate about what additional capabilities and investigations may be required to address the issues that remain outstanding. ?? 2000 Academic Press.

  15. The voices in the infant context: the polarization in evidence

    Directory of Open Access Journals (Sweden)

    Analúcia Morais Vieira

    2008-12-01

    Full Text Available This paper has the intention of reflecting on the subtleties of the discourse of the educators, assistants and the children, which happens in the early childhood daily routine, upon the polarization slant. What I call polarization has to do with the dualities of the discourse of the educators and children about their knowings and doings, such as right and wrong, speak and shut up, learn and play, start and end, beautiful and ugly, good and bad, viz, the existence of two poles for the discourse: a positive one and a negative one. In this text we support the idea that, in early childhood education, the educators, assistants and the children should pay more attention to their discourse, so that they could break with the polarization, avoiding undesirable results. Together, they may start to talk about the present moment as something of the now, and not as something that has a dual value. Besides, we believe that it is relevant that since the beginning of the schooldays of the children there be no polarization of the discourse by the adults that accompany them. Keywords: Early Childhood Education, Discourse, Polarization

  16. Realization of beam polarization at the linear collider and its application to EW processes

    Energy Technology Data Exchange (ETDEWEB)

    Franco-Sollova, F.

    2006-07-15

    The use of beam polarization at the future ILC e{sup +}e{sup -} linear collider will benefit the physics program significantly. This thesis explores three aspects of beam polarization: the application of beam polarization to the study of electroweak processes, the precise measurement of the beam polarization, and finally, the production of polarized positrons at a test beam experiment. In the first part of the thesis the importance of beam polarization at the future ILC is exhibited: the benefits of employing transverse beam polarization (in both beams) for the measurement of triple gauge boson couplings (TGCs) in the W-pair production process are studied. The sensitivity to anomalous TGC values is compared for the cases of transverse and longitudinal beam polarization at a center of mass energy of 500 GeV. Due to the suppressed contribution of the t-channel {nu} exchange, the sensitivity is higher for longitudinal polarization. For some physics analyses the usual polarimetry techniques do not provide the required accuracy for the measurement of the beam polarization (around 0.25% with Compton polarimetry). The second part of the thesis deals with a complementary method to measure the beam polarization employing physics data acquired with two polarization modes. The process of single-W production is chosen due to its high cross section. The expected precision for 500 fb{sup -1} and W{yields}{mu}{nu} decays only, is {delta}P{sub e{sup -}}/P{sub e{sup -}}=0.26% and {delta}P{sub e{sup +}}/P{sub e{sup +}}=0.33%, which can be further improved by employing additional W-decay channels. The first results of an attempt to produce polarized positrons at the E-166 experiment are shown in the last part of the thesis. The E-166 experiment, located at the Final Focus Test Beam at SLAC's LINAC employs a helical undulator to induce the emission of circularly polarized gamma rays by the beam electrons. These gamma rays are converted into longitudinally polarized electron

  17. Influence of casting procedures on the corrosion resistance of clinical dental alloys containing palladium.

    Science.gov (United States)

    Viennot, Stéphane; Lissac, Michèle; Malquarti, Guillaume; Dalard, Francis; Grosgogeat, Brigitte

    2006-05-01

    The aim of this study was to compare the in vitro corrosion resistance in artificial saliva of two palladium-silver alloys (a Pd-Ag (Pors on 4) and an Ag-Pd (Palliag LTG)), with and without casting defects; 1 nickel-chrome alloy and 1 high-gold alloy, cast under recommended conditions, served as controls. For each of the palladium-based alloys, three specimens corresponding to three different casting conditions were used: under recommended conditions, with the use of a graphite-containing investment and crucible, and by reusing the sprues and sprue button. The electrochemical tests were run in Fusayama-Meyer artificial saliva. The open-circuit potential was recorded in mV/SCE at t=24h. Then, potentiodynamic polarization was performed to measure the polarization resistance (R(p)) in kOmega cm(2) and the corrosion current (i(corr)) in microA cm(-2). Data were evaluated with one-way analysis of variance and multiple comparisons test (alpha=0.05). In addition, each specimen was examined by scanning electron microscopy. Compared to the control alloys, the electrochemical experiments in artificial saliva indicated satisfactory corrosion resistance for the Pd-Ag and Ag-Pd alloys; these results are related to their high noble metal content and stable substructure. The Pd-Ag alloy displayed superior electrochemical properties to those of the Ag-Pd alloy regardless of the casting condition. The use of the graphite-containing crucible and investment during the cast process did not dramatically reduce the corrosion resistance values, but the reuse of sprues and the sprue button did. The optimal corrosion resistance values were obtained for the alloys cast according to the recommended conditions.

  18. Magnetostatics of the uniformly polarized torus

    DEFF Research Database (Denmark)

    Beleggia, Marco; De Graef, Marc; Millev, Yonko

    2009-01-01

    We provide an exhaustive description of the magnetostatics of the uniformly polarized torus and its derivative self-intersecting (spindle) shapes. In the process, two complementary approaches have been implemented, position-space analysis of the Laplace equation with inhomogeneous boundary...... conditions and a Fourier-space analysis, starting from the determination of the shape amplitude of this topologically non-trivial body. The stray field and the demagnetization tensor have been determined as rapidly converging series of toroidal functions. The single independent demagnetization......-tensor eigenvalue has been determined as a function of the unique aspect ratio α of the torus. Throughout the range of values of the ratio, corresponding to a multiply connected torus proper, the axial demagnetization factor Nz remains close to one half. There is no breach of smoothness of Nz(α) at the topological...

  19. The Polar BEAR magnetic field experiment

    Science.gov (United States)

    Bythrow, P. F.; Potemra, T. A.; Zanetti, L. J.; Mobley, F. F.; Scheer, L.; Radford, W. E.

    1987-09-01

    The objectives and the instrumentation of the Polar BEAR magnetic field experiment are described along with the preliminary results from simultaneous measurements of Birkeland currents and UV auroral emissions. The experiment consists of an integrated sensor head, analog electronics, and digital electronics. The sensor head is a single unit containing sensor windings for each of the three orthogonal axes, oriented parrallel to the spacecraft coordinates; to minimize interference from spacecraft-generated magnetic fields, the sensor unit is located at the end of the +y solar panel. The digital electronics package is essentially identical to that flown on HILAT. A signal processor digitizes the analog outputs of the three orthogonal axes of the flux-gate magnetometer to a 13-bit resolution, yielding a magnetic field range of + or - 63,000 nT and a resolution of 15.2 nT. The full-resolution magnetic field values are recovered by data processing techniques on the ground.

  20. Production of polarized vector mesons off nuclei

    International Nuclear Information System (INIS)

    Kopeliovich, B. Z.; Nemchik, J.; Schmidt, Ivan

    2007-01-01

    Using the light-cone QCD dipole formalism we investigate manifestations of color transparency (CT) and coherence length (CL) effects in electroproduction of longitudinally (L) and transversally (T) polarized vector mesons. Motivated by forthcoming data from the HERMES experiment we predict both the A and Q 2 dependence of the L/T ratios for ρ 0 mesons produced coherently and incoherently off nuclei. For an incoherent reaction the CT and CL effects add up and result in a monotonic A dependence of the L/T ratio at different values of Q 2 . In contrast, for a coherent process the contraction of the CL with Q 2 causes an effect opposite to that of CT and we expect quite a nontrivial A dependence

  1. Polarized Neutron Reflectometry of Nickel Corrosion Inhibitors.

    Science.gov (United States)

    Wood, Mary H; Welbourn, Rebecca J L; Zarbakhsh, Ali; Gutfreund, Philipp; Clarke, Stuart M

    2015-06-30

    Polarized neutron reflectometry has been used to investigate the detailed adsorption behavior and corrosion inhibition mechanism of two surfactants on a nickel surface under acidic conditions. Both the corrosion of the nickel surface and the structure of the adsorbed surfactant layer could be monitored in situ by the use of different solvent contrasts. Layer thicknesses and roughnesses were evaluated over a range of pH values, showing distinctly the superior corrosion inhibition of one negatively charged surfactant (sodium dodecyl sulfate) compared to a positively charged example (dodecyl trimethylammonium bromide) due to its stronger binding interaction with the surface. It was found that adequate corrosion inhibition occurs at significantly less than full surface coverage.

  2. Polarized few-nucleon targets: new developments

    International Nuclear Information System (INIS)

    Haeusser, O.

    1992-09-01

    We discuss recent improvements in producing polarized few-nucleon targets for nuclear and particle physics experiments. The emphasis is on progress with polarized gas targets intended for experiments at electron and proton storage rings. (author) 54 refs., 1 tab

  3. {tau} polarization in SUSY cascade decays

    Energy Technology Data Exchange (ETDEWEB)

    Choi, S.Y. [Chonbuk Univ., Jeonju (Korea), Dept. of Physics and RIPC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hagiwara, K. [KEK National High Energy Physics, Tsukuba (Japan); Kim, Y.G. [Sejong Univ., Seoul (Korea). ARCSEC; Mawatari, K. [Korea Institute for Advanced Study, Seoul (Korea). School of Physics; Zerwas, P.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[KEK National High Energy Physics, Tsukuba (Japan)

    2006-12-15

    {tau} leptons emitted in cascade decays of supersymmetric particles are polarized. The polarization may be exploited to determine spin and mixing properties of the neutralinos and stau particles involved. (orig.)

  4. Summary of the polarized beam working group

    International Nuclear Information System (INIS)

    Wienands, U.; Dyck, O. van.

    1989-05-01

    The polarized beam working group reviewed the AGS Bookster and TRIUMF KAON Factory facilities, heard an overview of the subject of siberian snakes, discussed internal polarized gas targets, and made recommendations for further study

  5. Antimicrobial Resistance

    Science.gov (United States)

    ... least 10 countries (Australia, Austria, Canada, France, Japan, Norway, Slovenia, South Africa, Sweden and the United Kingdom ... plan Global report on surveillance Country situation analysis Policy to combat antimicrobial resistance More on antimicrobial resistance ...

  6. Ultra-wideband polarization insensitive UT-shaped metamaterial absorber

    Science.gov (United States)

    Karampour, Nasrollah; Nozhat, Najmeh

    2017-05-01

    In this paper, an ultra-wideband metamaterial absorber (MMA) with U and T shaped resonators has been proposed. The resonators and the ground plane consist of gold (Au) and titanium (Ti) layers. The resistive sheet effect of Ti layer and the resonance elements in the structure cause a broad absorption spectrum. The simulations are based on the finite element method (FEM) and the results show that the absorption of the proposed structure is more than 90% between 150 and 300 THz that is much larger than previous works. Moreover, by applying the interference theory, we have demonstrated that the simulation results are in good agreement with the theoretical results. The primary proposed MMA is polarization sensitive. Therefore, a polarization insensitive metamaterial absorber has been suggested. Also, because of the extra resonance elements the full width at 90% absorption increases about 35 THz. This ultra-wideband MMA has various applications in microbalometer, imaging, thermal emitters, photovoltaic, and energy harvesting.

  7. Spin dependence studies with the ZGS polarized proton beam

    International Nuclear Information System (INIS)

    Wicklund, A.B.

    1977-01-01

    Selected results are summarized of recent measurements using a polarized proton beam at the Argonne ZGS. The polarized target asymmetry and the beam-target spin correlation are measured in pp→pp at 6 and 12 GeV/c. Asymmetry is slowly varying with energy while spin correlation increases considerably from 6 to 12 GeV/c. The polarized parameters in pp→pp and pn→pn elastic scattering are compared. The data show that pp and pn polarizations tend to approach mirror symmetry as the energy increases. The effective mass spectrometer has been used to study the pp→pπ + n, pn→pπ - p reactions from 2 to 6 GeV/c. For small -t values (-t 2 ) these reactions are dominated by π exchange. At large -t values other mechanisms besides π-exchange become important. The 3-body diffraction dissociation reactions have been measured at 6 GeV/c with hydrogen and deuterium targets. The reactions are pp→pπ + π - (p); pd→pπ + π - (p+n). Comparison of hydrogen and deuterium cross section reveals a considerable coherent contribution of deuterium, which has an approximately 20% larger cross section per nucleon than hydrogen

  8. Remote biopsy darting and marking of polar bears

    Science.gov (United States)

    Pagano, Anthony M.; Peacock, Elizabeth; McKinney, Melissa A.

    2014-01-01

    Remote biopsy darting of polar bears (Ursus maritimus) is less invasive and time intensive than physical capture and is therefore useful when capture is challenging or unsafe. We worked with two manufacturers to develop a combination biopsy and marking dart for use on polar bears. We had an 80% success rate of collecting a tissue sample with a single biopsy dart and collected tissue samples from 143 polar bears on land, in water, and on sea ice. Dye marks ensured that 96% of the bears were not resampled during the same sampling period, and we recovered 96% of the darts fired. Biopsy heads with 5 mm diameters collected an average of 0.12 g of fur, tissue, and subcutaneous adipose tissue, while biopsy heads with 7 mm diameters collected an average of 0.32 g. Tissue samples were 99.3% successful (142 of 143 samples) in providing a genetic and sex identification of individuals. We had a 64% success rate collecting adipose tissue and we successfully examined fatty acid signatures in all adipose samples. Adipose lipid content values were lower compared to values from immobilized or harvested polar bears, indicating that our method was not suitable for quantifying adipose lipid content.

  9. Statistics of polarization speckle: theory versus experiment

    DEFF Research Database (Denmark)

    Wang, Wei; Hanson, Steen Grüner; Takeda, Mitsuo

    2010-01-01

    In this paper, we reviewed our recent work on the statistical properties of polarization speckle, described by stochastic Stokes parameters fluctuating in space. Based on the Gaussian assumption for the random electric field components and polar-interferometer, we investigated theoretically...... and experimentally the statistics of Stokes parameters of polarization speckle, including probability density function of Stokes parameters with the spatial degree of polarization, autocorrelation of Stokes vector and statistics of spatial derivatives for Stokes parameters....

  10. Some developments in polarized ion sources

    International Nuclear Information System (INIS)

    Witteveen, G.J.

    1979-01-01

    Investigations concerning an atomic beam source are presented and a new polarized ion source of a more universal type is introduced. Polarized and unpolarized beams of positively or negatively charged ions can be produced with this new version and the theoretical limits are a polarized negative hydrogen ion beam with an intensity of about 1 mH and a polarized proton beam with an intensity of 10 mH. (C.F.)

  11. Probing lateral magnetic nanostructures by polarized GISANS

    International Nuclear Information System (INIS)

    Kentzinger, E.; Frielinghaus, H.; Ruecker, U.; Ioffe, A.; Richter, D.; Brueckel, Th.

    2007-01-01

    While structural and magnetic lateral correlations in thin film materials can be investigated at the μm length scale by neutron off-specular scattering (OSS) with polarization analysis, they can also be investigated at the nm length scale by grazing incidence small-angle scattering of polarized neutrons (polarized GISANS). We exemplify this issue showing a combined OSS and GISANS study of the lateral correlations in a remanent polarizing supermirror

  12. Probing lateral magnetic nanostructures by polarized GISANS

    Science.gov (United States)

    Kentzinger, E.; Frielinghaus, H.; Rücker, U.; Ioffe, A.; Richter, D.; Brückel, Th.

    2007-07-01

    While structural and magnetic lateral correlations in thin film materials can be investigated at the μm length scale by neutron off-specular scattering (OSS) with polarization analysis, they can also be investigated at the nm length scale by grazing incidence small-angle scattering of polarized neutrons (polarized GISANS). We exemplify this issue showing a combined OSS and GISANS study of the lateral correlations in a remanent polarizing supermirror.

  13. Political Polarization and the Size of Government

    OpenAIRE

    Lindqvist, Erik; Östling, Robert

    2008-01-01

    We study the effect of political polarization on government spending and redistribution using the dispersion of self-reported political preferences as our measure of polarization. Politically polarized countries have lower levels of redistribution and government consumption. The relationship between political polarization and the size of government is stronger in democratic countries, indicating that the effect goes through the political system. The results are robust to a large set of contro...

  14. Baryon spectroscopy with polarization observables from CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Strauch, Steffen [Univ. of South Carolina, Columbia, SC (United States)

    2016-08-01

    Meson photoproduction is an important tool in the study of baryon resonances. The spectrum of broad and overlapping nucleon excitations can be greatly clarified by use of polarization observables. The N* program at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) includes experimental studies with linearly and circularly polarized tagged photon beams, longitudinally and transversely polarized nucleon targets, and recoil polarizations. An overview of these experimental studies and recent results will be given.

  15. Silicon photonic thermometer operating on multiple polarizations

    DEFF Research Database (Denmark)

    Guan, Xiaowei; Wang, Xiaoyan; Frandsen, Lars Hagedorn

    2016-01-01

    A silicon photonics optical thermometer simultaneously operating on the multiple polarizations is designed and experimentally demonstrated. Measured sensitivities are 86pm/°C and 48pm/°C for the transverse-electric and transverse-magnetic polarizations, respectively.......A silicon photonics optical thermometer simultaneously operating on the multiple polarizations is designed and experimentally demonstrated. Measured sensitivities are 86pm/°C and 48pm/°C for the transverse-electric and transverse-magnetic polarizations, respectively....

  16. Polarization Measurements in the Vacuum Ultraviolet

    Science.gov (United States)

    West, E. A.; Kobayashi, K.; Noble, M.

    2005-01-01

    This paper will describe the VUV polarization testing of the NSSTC Solar Ultraviolet Magnetograph (SUMI) optics. SUMI is being developed for a sounding rocket payload to prove the feasibility of making magnetic field measurements in the transition region. This paper will cover the polarization properties of the VUV calibration polarizers, the instrumental polarization of the VUV chamber, SUMI's toroidal varied-line-space gratings and the SUMI polarimeter.

  17. RHIC Polarized proton performance in run-8

    International Nuclear Information System (INIS)

    Montag, C.; Bai, M.; MacKay, W.W.; Roser, T.; Abreu, N.; Ahrens, L.; Barton, D.; Beebe-Wang, J.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Bunce, G.; Calaga, R.; Cameron, P.; Connolly, R.; D'Ottavio, T.; Drees, A.; Fedotov, A.V.; Fischer, W.; Ganetis, G.; Gardner, C.; Glenn, J.; Hayes, T.; Huang, H.; Ingrassia, P.; Kayran, D.A.; Kewisch, J.; Lee, R.C.; Lin, F.; Litvinenko, V.N.; Luccio, A.U.; Luo, Y.; Makdisi, Y.; Malitsky, N.; Marr, G.; Marusic, A.; Michnoff, R.; Morris, J.; Oerter, B.; Pilat, F.; Pile, P.; Robert-Demolaize, G.; Russo, T.; Satogata, T.; Schultheiss, C.; Sivertz, M.; Smith, K.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2008-01-01

    During Run-8, the Relativistic Heavy Ion Collider (RHIC) provided collisions of spin-polarized proton beams at two interaction regions. Physics data were taken with vertical orientation of the beam polarization, which in the 'Yellow' RHIC ring was significantly lower than in previous years. We present recent developments and improvements as well as the luminosity and polarization performance achieved during Run-8, and we discuss possible causes of the not as high as previously achieved polarization performance of the 'Yellow' ring.

  18. Drug Resistance

    Science.gov (United States)

    ... infected with a drug-resistant strain of HIV. Drug-resistance testing results are used to decide which HIV medicines to include in a person’s first HIV regimen. After treatment is started, drug-resistance testing is repeated if ...

  19. The influence of non-polar lipids on tear film dynamics

    KAUST Repository

    Bruna, M.

    2014-04-04

    © 2014 Cambridge University Press. In this paper we examine the effect that physiological non-polar lipids, residing on the surface of an aqueous tear film, have on the film evolution. In our model we track the evolution of the thickness of the non-polar lipid layer, the thickness of the aqueous layer and the concentration of polar lipids which reside at the interface between the two. We also utilise a force balance in the non-polar lipid layer in order to determine its velocity. We show how to obtain previous models in the literature from our model by making particular choices of the parameters. We see the formation of boundary layers in some of these submodels, across which the concentration of polar lipid and the non-polar lipid velocity and film thickness vary. We solve our model numerically for physically realistic parameter values, and we find that the evolution of the aqueous layer and the polar lipid layer are similar to that described by previous authors. However, there are interesting dynamics for the non-polar lipid layer. The effects of altering the key parameters are highlighted and discussed. In particular, we see that the Marangoni number plays a key role in determining how far over the eye the non-polar lipid spreads.

  20. Polarized Moessbauer transitions in mixed hyperfine interactions

    International Nuclear Information System (INIS)

    Barb, D.; Tarina, D.

    1975-01-01

    A contribution to the theory of elliptical polarization in the Moessbauer effect for transitions between mixed nuclear states is reported. A relation between the two-dimensional complex vector parameterization and the photon polarization density matrix was used in describing changes in the polarization of the gamma-ray involved. (A.K.)