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Sample records for relative complex permittivity

  1. Estimation of complex permittivity using loop antenna

    DEFF Research Database (Denmark)

    Lenler-Eriksen, Hans-Rudolph; Meincke, Peter

    2004-01-01

    A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna.......A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna....

  2. Measurement of complex permittivity of composite materials using waveguide method

    NARCIS (Netherlands)

    Tereshchenko, O.V.; Buesink, Frederik Johannes Karel; Leferink, Frank Bernardus Johannes

    2011-01-01

    Complex dielectric permittivity of 4 different composite materials has been measured using the transmissionline method. A waveguide fixture in L, S, C and X band was used for the measurements. Measurement accuracy is influenced by air gaps between test fixtures and the materials tested. One of the

  3. Complex permittivity and conductivity of poly (p-phenylenediazo ...

    Indian Academy of Sciences (India)

    Conducting polymer composites were prepared by in situ polymerization of glyoxal and -phenylenediamine in different solvents containing different amounts of PVC, and silica. The microwave conductivity and complex permittivity of each sample was measured. The effect of dopants like HClO4 and HCl on these dielectric ...

  4. Measurement of relative permittivity of LTCC ceramic at different temperatures

    Directory of Open Access Journals (Sweden)

    Qiulin Tan

    2014-02-01

    Full Text Available Devices based on LTCC (low-temperature co-fired ceramic technology are more widely applied in high temperature environments, and the temperature-dependent properties of the LTCC material play an important role in measurements of the characteristics of these devices at high temperature. In this paper, the temperature-dependence of the relative permittivity of DuPont 951 LTCC ceramic is studied from room temperature to 500 °C. An expression for relative permittivity is obtained, which relates the relative permittivity to the resonant frequency, inductance, parasitic capacitance and electrode capacitance of the LTCC sample. Of these properties, the electrode capacitance is the most strongly temperature-dependent. The LTCC sample resonant frequency, inductance and parasitic capacitance were measured (from room temperature to 500 °C with a high temperature measurement system comprising a muffle furnace and network analyzer. We found that the resonant frequency reduced and the inductance and parasitic capacitance increased slightly as the temperature increases. The relative permittivity can be calculated from experimental frequency, inductance and parasitic capacitance measurements. Calculating results show that the relative permittivity of DuPont 951 LTCC ceramic ceramic increases to 8.21 from room temperature to 500 °C.

  5. The effective complex permittivity stability in filled polymer nanocomposites studied above the glass transition temperature

    Directory of Open Access Journals (Sweden)

    Elhaouzi F.

    2018-01-01

    Full Text Available The temperature effecton the dielectric response of nanocomposite at low frequencies range is reported. The investigated samples are formed by a semi-crystalline ethylene-co-butyl acrylate (EBA polymer filled with three concentrations of the dispersed conducting carbon black (CB nanoparticles. The temperature dependence of the complex permittivity has been analyzedabove the glass transition temperature of the neat polymer matrix Tg=-75°C. For all CB concentrations, the dielectric spectra follow a same trend in frequency range 100-106Hz. More interestingly, the stability of the effective complex permittivity ɛ=ɛ' -iɛ'' with the temperature range of 10-70°C is explored. While the imaginary part of the complex permittivity ɛ'' exhibits a slight decreasewith temperature, the real part ɛ' shows a significant reduction especially for high loading samples. The observed dielectric response may be related to the breakup of the three-dimensional structurenetwork formed by the aggregation of CB particles causing change at the interfaceEBA-CB.This interface is estimated bythe volume fraction of constrained polymer chain according to loss tangent data of dynamic mechanical analysis.

  6. Lithium ferrite: The study on magnetic and complex permittivity characteristics

    Directory of Open Access Journals (Sweden)

    Madhavaprasad Dasari

    2017-03-01

    Full Text Available Lithium ferrite (Li0.5Fe2.5O4 powder was prepared by solid state reaction method, which was finally pressed and sintered at 1150 °C. The spinel structure of the lithium ferrite was confirmed by X-ray diffraction and grain size estimation was obtained from scanning electron microscope (SEM. Fourier transform infrared spectroscopy (FTIR confirmed the presence of primary and secondary absorption bands characteristic for spinel structure. The force constants were estimated using absorption bands for the lithium ferrite. Magnetization and dielectric studies were carried out for the sintered sample. Saturation magnetization (Ms of 59.6 emu/g was achieved and variation of magnetization with temperature was used to identify the Curie temperature. The complex permittivity (ε∗ for the lithium ferrite sample was obtained for wide frequency range up to 3 GHz and discussed based on available models. The Curie temperature was estimated around 480 °C and verified from both magnetization versus temperature and dielectric constant versus temperature measurements.

  7. A broadband variable-temperature test system for complex permittivity measurements of solid and powder materials

    Science.gov (United States)

    Zhang, Yunpeng; Li, En; Zhang, Jing; Yu, Chengyong; Zheng, Hu; Guo, Gaofeng

    2018-02-01

    A microwave test system to measure the complex permittivity of solid and powder materials as a function of temperature has been developed. The system is based on a TM0n0 multi-mode cylindrical cavity with a slotting structure, which provides purer test modes compared to a traditional cavity. To ensure the safety, effectiveness, and longevity, heating and testing are carried out separately and the sample can move between two functional areas through an Alundum tube. Induction heating and a pneumatic platform are employed to, respectively, shorten the heating and cooling time of the sample. The single trigger function of the vector network analyzer is added to test software to suppress the drift of the resonance peak during testing. Complex permittivity is calculated by the rigorous field theoretical solution considering multilayer media loading. The variation of the cavity equivalent radius caused by the sample insertion holes is discussed in detail, and its influence to the test result is analyzed. The calibration method for the complex permittivity of the Alundum tube and quartz vial (for loading powder sample), which vary with the temperature, is given. The feasibility of the system has been verified by measuring different samples in a wide range of relative permittivity and loss tangent, and variable-temperature test results of fused quartz and SiO2 powder up to 1500 °C are compared with published data. The results indicate that the presented system is reliable and accurate. The stability of the system is verified by repeated and long-term tests, and error analysis is presented to estimate the error incurred due to the uncertainties in different error sources.

  8. Effect of swift heavy Kr ions on complex permittivity of silicon PIN diode

    International Nuclear Information System (INIS)

    Li, Yun; Su, Ping; Yang, Zhimei; Ma, Yao; Gong, Min

    2016-01-01

    Highlights: • The complex permittivity has been studied on Si PIN irradiated by heavy Kr ions. • DLTS was used to investigate damages formed in PIN diode during irradiation. • The recombination of carriers has important influence on the complex permittivity. - Abstract: The complex permittivity has been researched on silicon PIN diodes irradiated by 2150 MeV heavy Kr ions in this article. The difference of complex permittivity spectra from 1 to 10^7 Hz between irradiated and unirradiated were observed and discussed. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics were measured at room temperature (300 K) to study the change of electrical properties in diode after irradiation. Deep level transient spectroscopy (DLTS) was used to investigate damages caused by 2150 MeV heavy Kr ions in diode. Two extra electron traps were observed, which were located at E C -0.31 eV and E C -0.17 eV. It indicated that new defects have been formed in PIN diode during irradiation. A comparison of the results illustrated that not only the carrier density but also the recombination of electron-hole pair have important influences on the properties of complex permittivity. These results offer a further indication of the mechanism about the complex permittivity property of semiconductor device, which could help to make the applications for the semiconductor device controlled by electric signals come true in the fields of optoelectronic integrated circuits, plasma antenna and so on.

  9. Relative permittivity in the electrical double layer from nonlinear optics

    Science.gov (United States)

    Boamah, Mavis D.; Ohno, Paul E.; Geiger, Franz M.; Eisenthal, Kenneth B.

    2018-06-01

    Second harmonic generation (SHG) spectroscopy has been applied to probe the fused silica/water interface at pH 7 and the uncharged 11 ¯ 02 sapphire/water interface at pH 5.2 in contact with aqueous solutions of NaCl, NaBr, NaI, KCl, RbCl, and CsCl as low as several 10 μM. For ionic strengths up to about 0.1 mM, the SHG responses were observed to increase, reversibly for all salts surveyed, when compared to the condition of zero salt added. Further increases in the salt concentration led to monotonic decreases in the SHG response. The SHG increases followed by decreases are found to be consistent with recent reports of phase interference and phase matching in nonlinear optics. By varying the relative permittivity employed in common mean field theories used to describe electrical double layers and by comparing our results to available literature data, we find that models recapitulating the experimental observations are the ones in which (1) the relative permittivity of the diffuse layer is that of bulk water, with other possible values as low as 30, (2) the surface charge density varies with salt concentration, and (3) the charge in the Stern layer or its thickness varies with salt concentration. We also note that the experimental data exhibit sensitivity depending on whether the salt concentration is increased from low to high values or decreased from high to low values, which, however, is not borne out in the fits, at least within the current uncertainties associated with the model point estimates.

  10. Complex permeability and permittivity variation of carbonyl iron rubber in the frequency range of 2 to 18 GHz

    Directory of Open Access Journals (Sweden)

    Adriana Medeiros Gama

    2010-04-01

    Full Text Available The complex dielectric permittivity (e and magnetic permeability (m of Radar Absorbing Materials (RAM based on metallic magnetic particles (carbonyl iron particles embedded in a dielectric matrix (silicon rubber have been studied in the frequency range of 2 to 18 GHz. The relative permeability and permittivity of carbonyl iron-silicon composites for various mass fractions are measured by the transmission/reflection method using a vector network analyzer. The concentration dependence of permittivity and permeability on the frequency is analyzed. In a general way, the results show that e´ parameter shows a more significant variation among the evaluated parameters (e”, m”, m’. The comparison of dielectric and magnetic loss tangents (e”/e” and m”/m’, respectively shows more clearly the variation of both parameters (e and m according to the frequency. It is also observed that higher carbonyl iron content fractions favor both dielectric and magnetic loss tangents.

  11. Effect of swift heavy Kr ions on complex permittivity of silicon PIN diode

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yun [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China); Su, Ping, E-mail: pingsu@scu.edu.cn [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Key Lab of Microelectronics Sichuan Province, Sichuan University, Chengdu, Sichuan 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China); Yang, Zhimei; Ma, Yao [Key Lab of Microelectronics Sichuan Province, Sichuan University, Chengdu, Sichuan 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China); Gong, Min, E-mail: mgong@scu.edu.cn [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Key Lab of Microelectronics Sichuan Province, Sichuan University, Chengdu, Sichuan 610064 (China); College of Physical Science and Technology, Sichuan University, Chengdu, Sichuan 610064 (China)

    2016-12-01

    Highlights: • The complex permittivity has been studied on Si PIN irradiated by heavy Kr ions. • DLTS was used to investigate damages formed in PIN diode during irradiation. • The recombination of carriers has important influence on the complex permittivity. - Abstract: The complex permittivity has been researched on silicon PIN diodes irradiated by 2150 MeV heavy Kr ions in this article. The difference of complex permittivity spectra from 1 to 10^7 Hz between irradiated and unirradiated were observed and discussed. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics were measured at room temperature (300 K) to study the change of electrical properties in diode after irradiation. Deep level transient spectroscopy (DLTS) was used to investigate damages caused by 2150 MeV heavy Kr ions in diode. Two extra electron traps were observed, which were located at E{sub C}-0.31 eV and E{sub C}-0.17 eV. It indicated that new defects have been formed in PIN diode during irradiation. A comparison of the results illustrated that not only the carrier density but also the recombination of electron-hole pair have important influences on the properties of complex permittivity. These results offer a further indication of the mechanism about the complex permittivity property of semiconductor device, which could help to make the applications for the semiconductor device controlled by electric signals come true in the fields of optoelectronic integrated circuits, plasma antenna and so on.

  12. Complex permittivity measurement at millimetre-wave frequencies during the fermentation process of Japanese sake

    International Nuclear Information System (INIS)

    Kouzai, Masaki; Nishikata, Atsuhiro; Fukunaga, Kaori; Miyaoka, Shunsuke

    2007-01-01

    Various chemical reactions occur simultaneously in barrels during the fermentation processes of alcoholic beverages. Chemical analyses are employed to monitor the change in chemical components, such as glucose and ethyl alcohol. The tests are carried out with extracted specimens, are costly and require time. We have developed a permittivity measurement system for liquid specimens in the frequency range from 2.6 to 50 GHz, and applied the system to fermentation monitoring. Experimental results proved that the observed change in complex permittivity suggests a decrease in the amount of glucose and an increase in alcohol content, which are the key chemical components during the fermentation process

  13. Determination of the element-specific complex permittivity using a soft x-ray phase modulator

    Science.gov (United States)

    Kubota, Y.; Hirata, Y.; Miyawaki, J.; Yamamoto, S.; Akai, H.; Hobara, R.; Yamamoto, Sh.; Yamamoto, K.; Someya, T.; Takubo, K.; Yokoyama, Y.; Araki, M.; Taguchi, M.; Harada, Y.; Wadati, H.; Tsunoda, M.; Kinjo, R.; Kagamihata, A.; Seike, T.; Takeuchi, M.; Tanaka, T.; Shin, S.; Matsuda, I.

    2017-12-01

    We report on directly determining the complex permittivity tensor using a method combining a developed light source from a segmented cross undulator of synchrotron radiation and the magneto-optical Kerr effect. The empirical permittivity, which carries the electronic and magnetic information of a material, has element specificity and has perfect confirmation using the quantum-mechanical calculation for itinerant electrons systems. These results help in understanding the interaction of light and matter, and they provide an interesting approach to seek the best materials as optical elements, for example, in extended-ultraviolet lithographic technologies or in state-of-the-art laser technologies.

  14. In vivo and in situ measurement and modelling of intra-body effective complex permittivity

    DEFF Research Database (Denmark)

    Nadimi, Esmaeil S; Blanes-Vidal, Victoria; Harslund, Jakob L F

    2015-01-01

    Radio frequency tracking of medical micro-robots in minimally invasive medicine is usually investigated upon the assumption that the human body is a homogeneous propagation medium. In this Letter, the authors conducted various trial programs to measure and model the effective complex permittivity e...

  15. TDR measurements looking for complex dielectric permittivity and complex magnetic permeability in lossy materials

    Science.gov (United States)

    Persico, Raffaele

    2017-04-01

    TDR probes can be exploited for the measure of the electromagnetic characteristics of the soil, or of any penetrable material. They are commonly exploited as instruments for the measure of the propagation velocity of the electromagnetic waves in the probed medium [1], in its turn useful for the proper focusing of GPR data [2-5]. However, a more refined hardware and processing can allow to extrapolate from these probes also the discrimination between dielectric and magnetic characteristics of the material under test, which can be relevant for a better interpretation of the buried scenario or in order to infer physical-chemical characteristics of the material at hand. This requires a TDR probe that can work in frequency domain, and in particular that allows to retrieve the reflection coefficient at the air soil interface. It has been already shown [6] that in lossless cases this can be promising. In the present contribution, it will be shown at the EGU conference that it is possible to look for both the relative complex permittivity and the relative magnetic permeability of the probed material, on condition that the datum has an acceptable SNR and that some diversity of information is guaranteed, either by multifrequency data or by a TDR that can prolong its arms in the soil. References [1] F. Soldovieri, G. Prisco, R. Persico, Application of Microwave Tomography in Hydrogeophysics: some examples, Vadose Zone Journal, vol. 7, n. 1 pp. 160-170, Feb. 2008. [2] I. Catapano, L. Crocco, R. Persico, M. Pieraccini, F. Soldovieri, "Linear and Nonlinear Microwave Tomography Approaches for Subsurface Prospecting: Validation on Real Data", IEEE Trans. on Antennas and Wireless Propagation Letters, vol. 5, pp. 49-53, 2006. [3] G. Leucci, N. Masini, R. Persico, F. Soldovieri." GPR and sonic tomography for structural restoration : the case of the Cathedral of Tricarico", Journal of Geophysics and Engineering, vol. 8, pp. S76-S92, Aug. 2011. [4] S. Piscitelli, E. Rizzo, F. Cristallo

  16. Measurements in Vacuum of the Complex Permittivity of Planetary Regolith Analog Materials in Support of the OSIRIS-REx Mission

    Science.gov (United States)

    Boivin, A.; Hickson, D. C.; Cunje, A.; Tsai, C. A.; Ghent, R. R.; Daly, M. G.

    2017-12-01

    In preparation for the OSIRIS-REx sample return mission, ground based radar data have been used to help characterize the carbonaceous asteroid (101955) Bennu as well as to produce a 3-D shape model. Radar data have also been used to derive the near-surface bulk density of the asteroid, a key engineering factor for sample acquisition and return. The relationship between radar albedo and bulk density of the nearsurface depends on the relative permittivity of the material, in this case regolith. The relative permittivity is complex such that ɛ r = ɛ r' + i ɛ r'', where ɛ r' is the dielectric constant and ɛ r'' is the loss factor. Laboratory permittivity measurements have been made in the past on a myriad of samples including Earth materials, lunar Apollo and analog samples, Mars soil analog samples, some meteorites, and cometary analog samples in support of the Rosetta mission. These measurements have been made in different frequency bands and in various conditions; however, no measurements to date have systematically explored the effect of changes in mineralogy on the complex permittivity, and particularly the loss tangent (tanδ , the ratio of ɛ r'' to ɛ r'). The loss tangent controls the absorption of the signal by the material. Continuing our investigation of the effects of mineralogy on these properties, we will present for the first time results of complex permittivity measurements of the UCF/DSI-CI-2 CI asteroid regolith simulant produced by Deep Space Industries Inc. The simulant is mineralogically similar to the CI meteorite Orgueil. CI meteorites are the most spectrally similar meteorites to (101955) Bennu. Since the simulant has been provided to us un-mixed, several sub-samples will be created containing different amounts of carbon, thus allowing us to systematically investigate the effects of carbon content on the permittivity. In order to remove moisture from our samples, powders are baked at 250°C for 48hrs prior to being loaded into a coaxial

  17. Enhancing relative permittivity by incorporating PDMS-PEG multiblock copolymers in binary polymer blends

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Szabo, Peter; Skov, Anne Ladegaard

    Polydimethylsiloxane (PDMS) elastomers are well-known to be soft and highly stretchable, yet they never achieve maximum elongation when utilised as dielectric elastomers, simply because their dielectric permittivity remains rather low. Conversely, polyethyleneglycols (PEG) are not stretchable......, but they do possess high permittivity. Combining two such polymers in a block copolymer allows for further crosslinking and presents the possibility of substantial improvements in the actuation response of the resulting dielectric elastomer – if carefully designed. The objective is to synthesise a PDMS......, the discontinuity in PEG can be acquired and the relative permittivity (ε’) is significantly enhanced (60%) with 5wt% of PDMS-PEG block copolymer incorporated into the silicone elastomer....

  18. Complex bounds and microstructural recovery from measurements of sea ice permittivity

    International Nuclear Information System (INIS)

    Gully, A.; Backstrom, L.G.E.; Eicken, H.; Golden, K.M.

    2007-01-01

    Sea ice is a porous composite of pure ice with brine, air, and salt inclusions. The polar sea ice packs play a key role in the earth's ocean-climate system, and they host robust algal and bacterial communities that support the Arctic and Antarctic ecosystems. Monitoring the sea ice packs on global or regional scales is an increasingly important problem, typically involving the interaction of an electromagnetic wave with sea ice. In the quasistatic regime where the wavelength is much longer than the composite microstructural scale, the electromagnetic behavior is characterized by the effective complex permittivity tensor ε*. In assessing the impact of climate change on the polar sea ice covers, current satellites and algorithms can predict ice extent, but the thickness distribution remains an elusive, yet most important feature. In recent years, electromagnetic induction devices using low frequency waves have been deployed on ships, helicopters and planes to obtain thickness data. Here we compare two sets of theoretical bounds to extensive outdoor tank and in situ field data on ε* at 50MHz taken in the Arctic and Antarctic. The sea ice is assumed to be a two phase composite of ice and brine with known constituent permittivities. The first set of bounds assumes only knowledge of the brine volume fraction or porosity, and the second set further assumes statistical isotropy of the microstructure. We obtain excellent agreement between theory and experiment, and are able to observe the apparent violation of the isotropic bounds as the vertically oriented microstructure becomes increasingly connected for higher porosities. Moreover, these bounds are inverted to obtain estimates of the porosity from the measurements of ε*. We find that the temporal variations of the reconstructed porosity, which is directly related to temperature, closely follow the actual behavior

  19. How the relative permittivity of solar cell materials influences solar cell performance

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Huss-Hansen, Mathias K.; Hansen, Ole

    2017-01-01

    of the materials permittivity on the physics and performance of the solar cell by means of numerical simulation supported by analytical relations. We demonstrate that, depending on the specific solar cell configuration and materials properties, there are scenarios where the relative permittivity has a major......The relative permittivity of the materials constituting heterojunction solar cells is usually not considered as a design parameter when searching for novel combinations of heterojunction materials. In this work, we investigate the validity of such an approach. Specifically, we show the effect...... the heterojunction partner has a high permittivity, solar cells are consistently more robust against several non-idealities that are especially likely to occur in early-stage development, when the device is not yet optimized....

  20. Analytical Method to Estimate the Complex Permittivity of Oil Samples

    Directory of Open Access Journals (Sweden)

    Lijuan Su

    2018-03-01

    Full Text Available In this paper, an analytical method to estimate the complex dielectric constant of liquids is presented. The method is based on the measurement of the transmission coefficient in an embedded microstrip line loaded with a complementary split ring resonator (CSRR, which is etched in the ground plane. From this response, the dielectric constant and loss tangent of the liquid under test (LUT can be extracted, provided that the CSRR is surrounded by such LUT, and the liquid level extends beyond the region where the electromagnetic fields generated by the CSRR are present. For that purpose, a liquid container acting as a pool is added to the structure. The main advantage of this method, which is validated from the measurement of the complex dielectric constant of olive and castor oil, is that reference samples for calibration are not required.

  1. Phenomenological model to fit complex permittivity data of water from radio to optical frequencies.

    Science.gov (United States)

    Shubitidze, Fridon; Osterberg, Ulf

    2007-04-01

    A general factorized form of the dielectric function together with a fractional model-based parameter estimation method is used to provide an accurate analytical formula for the complex refractive index in water for the frequency range 10(8)-10(16)Hz . The analytical formula is derived using a combination of a microscopic frequency-dependent rational function for adjusting zeros and poles of the dielectric dispersion together with the macroscopic statistical Fermi-Dirac distribution to provide a description of both the real and imaginary parts of the complex permittivity for water. The Fermi-Dirac distribution allows us to model the dramatic reduction in the imaginary part of the permittivity in the visible window of the water spectrum.

  2. Complex Permittivity Measurements of Textiles and Leather in a Free Space: An Angular-Invariant Approach

    OpenAIRE

    Kapilevich, B.; Litvak, B.; Anisimov, M.; Hardon, D.; Pinhasi, Y.

    2012-01-01

    The paper describes the complex permittivity measurements of textiles and leathers in a free space at 330 GHz. The destructive role of the Rayleigh scattering effect is considered and the angular-invariant limit for an incidence angle has been found out experimentally within 25–30 degrees. If incidence angle exceeds this critical parameter, the uncertainty caused by the Rayleigh scattering is drastically increased preventing accurate measurements of the real and imaginary parts of a bulky mat...

  3. Microwave absorbing property and complex permittivity and permeability of graphene–CdS nanocomposite

    International Nuclear Information System (INIS)

    Zhang, Dong-Dong; Zhao, Dong-Lin; Zhang, Ji-Ming; Bai, Li-Zhong

    2014-01-01

    Graphical abstract: Graphene–CdS (G–CdS) nanocomposite with a good structural interface and enhanced microwave absorption has been successfully and directly synthesized from graphene oxide via a facile hydrothermal approach. The permittivity of G–CdS nanocomposite presents triple dielectric relaxations by constructing a good structural G–CdS interface. The triple dielectric relaxations are critical to improve the microwave absorption of the G–CdS nanocomposite. Highlights: • Graphene–CdS (G–CdS) nanocomposite was directly synthesized from graphene oxide. • The G–CdS nanocomposite exhibits enhanced microwave absorption. • The permittivity of G–CdS nanocomposite presents triple dielectric relaxations. -- Abstract: The graphene–CdS (G–CdS) nanocomposite with enhanced microwave absorption was directly synthesized from graphene oxide (GO) via a facile hydrothermal approach, during which the formation of CdS nanoparticles and the reduction of GO occured simultaneously. The morphology, structure, microwave absorbing property, complex permittivity and permeability of G–CdS nanocomposite were systematically investigated by transmission electron microscope, X-ray diffraction and the coaxial line method. The complex permittivity of G–CdS nanocomposite presents triple dielectric relaxations with constructing a good structural graphene–CdS interface. The triple dielectric relaxations were critical to improve the microwave absorption of G–CdS nanocomposite. The G–CdS nanocomposite achieved a reflection loss below –10 dB in the frequency range of 5.2–18 GHz when adjusting the thicknesses from 2 to 5 mm, which was mainly ascribed to the proper electromagnetic matching of the CdS nanoparticles and graphene sheets, and the triple dielectric relaxations. The G–CdS nanocomposite is promising as a lightweight and wide-frequency microwave absorber

  4. Complex Permittivity of Polyaniline-Carbon Nanotube and Nanofibre Composites in the X-band. PMMA Composites

    National Research Council Canada - National Science Library

    Makeiff, Darren A; Huber, Trisha; Saville, Paul

    2005-01-01

    ... the complex permittivity from transmission-reflection waveguide measurements in the X-band (8-12 GHz). PMMA composites containing PAni-MWNT or PAni-CNFs poorer, while PMMA composites containing PAni and MWNT mixed ex situ...

  5. Radiometric characterization of six soils in the microwave X-range through complex permittivity measurements

    International Nuclear Information System (INIS)

    Palme, U.W.

    1987-10-01

    Estimating and monitoring up-to-date soil moisture conditions over extensive areas through passive (or active) microwave remote sensing techniques requires the knowledge of the complex relative permittivity (ε r * ) in function of soil moisture. X-band measurements of ε r * for different moisture conditions were made in laboratory for soil samples of six important Soils (PV 2 , LV 3 , LR d , LE 1 , SAP and Sc). Using a theoretical model and computational programmes developed, these measurements allowed estimates of the emissive characteristics of the soils that would be expected with the X-Band Microwave Radiometer built at INPE. The results, new, for soils from tropical regions, showed that only the physical characteristics and properties of the soils are not sufficient to explain the behaviour of ε r * in function of soil moisture, indicating that the chemical and/or mineralogical properties of the soils do have an important contribution. The results also showed thast ε r * in function of soil moisture depends on soil class. (author) [pt

  6. Estimation of Relative Permittivity of Printed Circuit Board with Fiber Glass Epoxy as Dielectric for UHF Applications

    Directory of Open Access Journals (Sweden)

    Ronal D. Montoya-Montoya

    2013-11-01

    Full Text Available This paper presents the results of measuring relative permittivity of fiber glass printed circuit board (PCB’s, using a rectangular resonant cavity. The relative permittivity is presented as function of frequency. To obtain resonant frequencies, the return loss was measured using a network analyzer. Relative permittivity was calculated by finding frequencies of resonant cavity modes. The results are presented in a frequency span of 1 to 3.5GHz. It was clearly shown the nonlinear behavior of the relative permittivity for the dielectric laminate evaluated, even what happens respect to the frequency of the resonant modes below and above to frequency of 2 GHz.

  7. Exact Cavity Perturbation Technique to Determine Complex Permittivity of Dielectric Materials

    Science.gov (United States)

    Starr, Charles H.; Barmatz, Martin B.

    2011-01-01

    Cassini is an international spacecraft mission facilitated by NASA and ESA which seeks to understand the Saturn planetary system, including rings and moons. Launched in 1997, the Cassini spacecraft contains two major components: the Cassini orbiter that has been orbiting Saturn since October 2004, and the European-built Huygens probe that landed on Titan's surface in December 2004 to study its geology and atmosphere. Titan, Saturn's largest moon and the second largest moon in the solar system, possesses surface and atmospheric features similar to those of Earth, including lakes, seas, and mountains. A physical characterization of these features is critical to understanding the origin and evolution of Titan, whose surface composition reflects its geological history. Because Titan's atmosphere is largely composed of methane, it is believed that surfaces lakes are filled with mixtures of liquid hydrocarbons. The Cassini orbiter's RADAR instrument has been scanning Titan's surface at the atmosphere-penetrating microwave frequency of 13.8 Gigahertz since 2004. However, accurate interpretation of these data is limited by a lack of knowledge regarding dielectric properties of liquid hydrocarbons at cryogenic temperatures. Therefore, it is of specific interest to experimentally determine values for the complex permittivities of various liquid hydrocarbon mixtures at the surface conditions of Titan. In particular, more accurate values for complex permittivity would improve estimates of lake depth and surface composition obtained from the instrument's altimetry and backscatter modes.

  8. Enhancing relative permittivity by incorporating PDMS-PEG multi block copolymers in binary polymer blends

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Szabo, Peter; Skov, Anne Ladegaard

    Polydimethylsiloxanes (PDMS) are well-known to actuate with relatively large strains due to low modulus, but they possess lowpermittivity. Contrary, polyethyleneglycols (PEG) are not stretchable but possess high permittivity. Combination of the two polymers in a block copolymer depicts a possibil......Polydimethylsiloxanes (PDMS) are well-known to actuate with relatively large strains due to low modulus, but they possess lowpermittivity. Contrary, polyethyleneglycols (PEG) are not stretchable but possess high permittivity. Combination of the two polymers in a block copolymer depicts...... a possibility for substantial improvement of properties such as high permittivity, stretchability and non-conductivity – if carefully designed. The objective is to synthesize PDMS-PEG multiblock copolymer assembling into discontinuous morphologies in PEG based on variation of volume fractions of PDMS....... The utilized synthesis of PDMS-PEG multiblock copolymer is based on hydrosilylation reaction, which is amended from Klasner et al.1 and Jukarainen etal.2 Variation in the ratio between the two constituents introduces distinctive properties in terms of dielectric permittivity and rheological behaviour. PDMS...

  9. Complex dielectric permittivity and dielectric relaxation of heavy water along its curve of existence

    Energy Technology Data Exchange (ETDEWEB)

    Nabokov, O.A.; Lyubimov, Yu.A.

    1985-10-01

    The authors previously studied the complex dielectric permittivity of ordinary water at 70-200/sup 0/C. Similar measurements were performed in this work for D/sub 2/O by incomplete filling of a microwave resonator at a frequency of about 9.3 GHz. Distilled 99.8% D/sub 2/O was used. For D/sub 2/O, the value of tau/sub D/T/eta (where eta is the viscosity) increases with increasing temperature, so that at 140/sup 0/C its change goes beyond the limits of error of the measurement of tau/sub D/ and eta. The gradual increase in tau/sub D/T/eta and tau/sub D/D with temperature indicates weakening of the interaction between orientation and translation movements of the liquid D/sub 2/O molecules with increasing temperature. 11 references, 1 figure.

  10. Relative Permittivity of Carbon Dioxide + Ethanol Mixtures prediction by means of Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Gonzalo Astray

    2014-07-01

    Full Text Available CO2 + ethanol mixtures have a huge scientific interest and enormous relevance for many industrial processes. Obtaining of their chemical and physical properties is a fundamental task. Relative permittivity (r of these mixtures is a key property because allows a better knowledge of the structure and the interactions in other media. In this work predictive values of relative permittivity (r of carbon dioxide + ethanol mixtures were obtained implementing artificial neural networks (ANNs. They are used successfully in very different fields; therefore it is a very useful tool. In this case the obtained results enhance the ones from the usual multiple linear regression analysis. In both cases mass fraction, pressure and temperature experimental data from a direct capacitance method were used.

  11. TEMPERATURE TRENDS OF THE PERMITTIVITY IN COMPLEX OXIDES OF RARE-EARTH ELEMENTS WITH PEROVSKITE-TYPE STRUCTURE

    Directory of Open Access Journals (Sweden)

    A.G.Belous

    2003-01-01

    Full Text Available Ceramic materials based on complex oxides with both the perovskite structure (Ln2/3Nb2O6 and the structure of tetragonal tungsten bronze (Ba6-xLn8+2x/3Ti18O54 have been investigated over a wide frequency and temperature ranges. The results obtained for certain structures denote the presence of the temperature anomalies of dielectric parameters (ε, tanδ. These anomalies occur over the wide frequency range including submilimeter (SMM wavelength range, and are related neither with the processing peculiarities nor with the presence of the phase transitions. Temperature behavior of the permittivity has been considered in terms of the polarization mechanism based on the elastic-strain lattice oscillations. It has been assumed that the observed anomalies could be ascribed to a superposition of harmonic and anharmonic contribution to lattice oscillations that determines τε sign and magnitude.

  12. Measuring the complex permittivity tensor of uniaxial biological materials with coplanar waveguide transmission line

    Science.gov (United States)

    A simple and accurate technique is described for measuring the uniaxial permittivity tensor of biological materials with a coplanar waveguide transmission-line configuration. Permittivity tensor results are presented for several chicken and beef fresh meat samples at 2.45 GHz....

  13. Broadband permittivity measurements on porous planetary regoliths simulants, in relation with the Rosetta mission to 67P/C-G

    Science.gov (United States)

    Brouet, Yann; Levasseur-Regourd, Anny-Chantal; Encrenaz, Pierre; Sabouroux, Pierre; Heggy, Essam; Kofman, Wlodek; Thomas, Nick

    2015-04-01

    The Rosetta mission has successfully rendezvous comet 67P/Churyumov-Gerasimenko (hereafter 67P) last year and landed Philae module on its nucleus on 12 November it 2014. Among instruments onboard Rosetta, MIRO [1], composed of two radiometers, with receivers at 190 GHz and 563 GHz (center-band), is dedicated to the measurements of the subsurface and surface brightness temperatures. These values depend on the complex relative permittivity (hereafter permittivity) with ɛ' and ɛ'' the real and imaginary parts. The permittivity of the material depends on frequency, bulk density/porosity, composition and temperature [2]. Considering the very low bulk density of 67P nucleus (about 450 kg.m-3 [3]) and the suspected presence of a dust mantle in many areas of the nucleus [4], investigations on the permittivity of porous granular samples are needed to support the interpretation of MIRO data, as well as of other microwave experiments onboard Rosetta, e.g. CONSERT [5], a bistatic penetrating radar working at 90 MHz. We have developed a programme of permittivity measurements on porous granular samples over a frequency range from 50 MHz to 190 GHz under laboratory conditions (e.g. [6] and [7]). We present new results obtained on JSC-1A lunar soil simulant and ashes from Etna. The samples were split into several sub-samples with different size ranges covering a few to 500 μm. Bulk densities of the sub-samples were carefully measured and found to be in the 800-1400 kg.m-3 range. Sub-samples were also dried and volumetric moisture content was found to be below 0.6%. From 50 MHz to 6 GHz and at 190 GHz, the permittivity has been determined, respectively with a coaxial cell and with a quasi-optical bench mounted in transmission, both connected to a vector network analyzer. The results demonstrate the dispersive behaviours of ɛ' between 50 MHz and 190 GHz. Values of ɛ' remain within the 3.9-2.6 range for all sub-samples. At CONSERT frequency, ɛ'' is within the 0.01-0.09 range

  14. Coaxial Sensors For Broad-Band Complex Permittivity Measurements of Petroleum Fluids

    Energy Technology Data Exchange (ETDEWEB)

    Folgeroe, K.

    1996-12-31

    This doctoral thesis verifies that dielectric spectroscopy and microwave permittivity measurements can be used to characterize petroleum liquids. It concentrates on developing sensors for three potential industrial applications: quality characterization of crude oil and petroleum fractions, monitoring of gas-hydrate formation in water-in-oil emulsions, and determination of water-content in thin liquid layers. The development of a permittivity measurement system for crude oil and petroleum fractions is described. As black oils have low dielectric constant and loss, the system must be very sensitive in order to measure the dielectric spectra and to distinguish oils of different permittivity. Such a system was achieved by combining impedance and scattering parameter measurements with appropriate permittivity calculation methods. The frequency range from 10 kHz to 6 GHz was found convenient for observing the main dispersion of the oils. All the oils had dielectric constants between 2.1 and 2.9 and dielectric loss below 0.01. The oils studied were samples of the feedstock for the cracker and coke processes at a petroleum refinery. This verifies that dielectric spectroscopy is a potential technique for on-line quality monitoring of the feedstock at petroleum refineries. Gas hydrates may cause major problems like clogging of pipelines. Dielectric spectroscopy is proposed as a means of monitoring the formation of gas hydrates in emulsions. It is found that open-ended coaxial probes fulfill the sensitivity requirements for such sensors. 312 refs., 87 figs., 20 tabs.

  15. Voltage-stabilised elastomers with increased relative permittivity and high electrical breakdown strength by means of phase separating binary copolymer blends of silicone elastomers

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Yu, Liyun; Skov, Anne Ladegaard

    2017-01-01

    Increased electrical breakdown strength and increased dielectric permittivity of silicone-based dielectric elastomers are achieved by means of the addition of so-called voltage-stabilisers prepared from PDMS–PPMS copolymers as well as PDMS–PEG copolymers in order to compensate for the negative...... effect of softness on electrical stability of silicone elastomers. The voltage-stabilised elastomer, incorporating a high-permittivity PDMS–PEG copolymer, possesses increased relative permittivity, high electrical breakdown strength, excellent network integrity and low dielectric loss and paves the way...

  16. OPTIMIZATION OF SURFACE RESISTIVITY AND RELATIVE PERMITTIVITY OF SILICONE RUBBER FOR HIGH VOLTAGE APPLICATION USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    N.N. Ali

    2017-06-01

    Full Text Available Silicone Rubber (SiR is considered as one of the most established insulator in High Voltage (HV industry. SiR possess a great function ability such as its lighter weight, great heat resistance and substantial electrical insulation properties. Dynamic research were performed all around the world in order to explore the unique insulating behavior of SiR but very little are done on the optimization of SiR in term of their processing parameters and formulation. In this work, four materials and processing factors were introduced; A: Alumina Trihydrate (ATH, B: Dicumyl-Peroxide (DCP, C: mixing speed and D: mixing time in order to analyze its contribution towards improving the surface resistivity and relative permittivity of SIR rubber. The factors range were set based on prior screening and are defined as; ATH (10 – 50 pphr, Dicumyl Peroxide (0.50 -1.50 pphr, speed of mixer (40 – 70 rpm and mixing period (5 – 10 mins which were then varied accordingly to produce an overall 19 samples of SiR blends. The testing results were analyzed using statistical Design of Experiment (DOE by applying two level full factorial from Design Expert Software (v10 to discover the inter-correlation between the factors studied and benefaction of each factor in improving both surface resistivity and relative permittivity responses of produced SiR blends. The model analysis on surface resistivity shows the coefficient of determination R2 value of 88.72% while the one for relative permittivity shows R2 value of 82.34 %. Combination of both dependent variables had yielded an optimization suggestion for SiR formulation and processing strategy of ATH: 50 pphr, DCP: 0.50 pphr, mixing speed: 70 rpm and mixing period: 10 mins with the desirability level of 0.835. The optimized formulation had resulted in the production of SiR blend with the characteristic of surface resistivity of 1.02039x10^14 Ω/sq and relative permittivity of 4.0231, respectively. In conclusion, it can be

  17. Presentation of a complex permittivity-meter with applications for sensing the moisture and salinity of a porous media.

    Science.gov (United States)

    Chavanne, Xavier; Frangi, Jean-Pierre

    2014-08-26

    This paper describes a sensor dedicated to measuring the vertical profile of the complex permittivity and the temperature of any medium in which sensor electrodes are inserted. Potential applications are the estimate of the humidity and salinity in a porous medium, such as a soil. It consists of vertically-stacked capacitors along two conductive parallel cylinders of 5 cm in diameter and at a 10-cm distance to scan a significant volume of the medium (~1 L). It measures their admittances owing to a self-balanced impedance bridge operating at a frequency in the range of 1-20 MHz, possibly 30 MHz. Thanks to accurate design and electronic circuit theory-based modeling, the determination of the admittances takes into account all distortions due to lead and bridge electromagnetic effects inside the sensor when working at high frequencies. Calibration procedures and uncertainties are presented. The article also describes developments to make the present sensor autonomous on digital acquisition, basic data treatment and energy, as well as able to transfer stored data by a radio link. These steps in progress are prerequisites for a wireless network of sensors.

  18. Presentation of a Complex Permittivity-Meter with Applications for Sensing the Moisture and Salinity of a Porous Media

    Directory of Open Access Journals (Sweden)

    Xavier Chavanne

    2014-08-01

    Full Text Available This paper describes a sensor dedicated to measuring the vertical profile of the complex permittivity and the temperature of any medium in which sensor electrodes are inserted. Potential applications are the estimate of the humidity and salinity in a porous medium, such as a soil. It consists of vertically-stacked capacitors along two conductive parallel cylinders of 5 cm in diameter and at a 10-cm distance to scan a significant volume of the medium (~1 L. It measures their admittances owing to a self-balanced impedance bridge operating at a frequency in the range of 1–20 MHz, possibly 30 MHz. Thanks to accurate design and electronic circuit theory-based modeling, the determination of the admittances takes into account all distortions due to lead and bridge electromagnetic effects inside the sensor when working at high frequencies. Calibration procedures and uncertainties are presented. The article also describes developments to make the present sensor autonomous on digital acquisition, basic data treatment and energy, as well as able to transfer stored data by a radio link. These steps in progress are prerequisites for a wireless network of sensors.

  19. Influence of thermal stress on the relative permittivity of the AlGaN barrier layer in an AlGaN/GaN heterostructure Schottky contacts

    International Nuclear Information System (INIS)

    Lü Yuan-Jie; Lin Zhao-Jun; Zhang Yu; Meng Ling-Guo; Cao Zhi-Fang; Luan Chong-Biao; Chen Hong; Wang Zhan-Guo

    2011-01-01

    Ni Schottky contacts on AlGaN/GaN heterostructures were fabricated. Some samples were thermally treated in a furnace with N 2 ambience at 600 °C for different times (0.5 h, 4.5 h, 10.5 h, 18 h, 33 h, 48 h, and 72 h), the others were thermally treated for 0.5 h at different temperatures (500 °C, 600 °C, 700 °C, and 800 °C). With the measured current—voltage (I—V) and capacitance—voltage (C—V) curves and by self-consistently solving Schrodinger's and Poisson's equations, we found that the relative permittivity of the AlGaN barrier layer was related to the piezoelectric and the spontaneous polarization of the AlGaN barrier layer. The relative permittivity was in proportion to the strain of the AlGaN barrier layer. The relative permittivity and the strain reduced with the increased thermal stress time until the AlGaN barrier totally relaxed (after 18 h at 600 °C in the current study), and then the relative permittivity was almost a constant with the increased thermal stress time. When the sample was treated at 800 °C for 0.5 h, the relative permittivity was less than the constant due to the huge diffusion of the contact metal atoms. Considering the relation between the relative permittivity of the AlGaN barrier layer and the converse piezoelectric effect, the conclusion can be made that a moderate thermal stress can restrain the converse piezoelectric effect and can improve the stability of AlGaN/GaN heterostructure devices. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  20. Relations between temperature coefficients of permittivity and elastic compliances in PZT ceramics near the morphotropic phase boundary.

    Science.gov (United States)

    Boudys, M

    1991-01-01

    Variations of temperature coefficients of permittivity epsilon(33)(T), elastic compliances at constant electric fields s(11)(E), and constant polarization s(11)(P) with a Zr/Ti ratio of Pb(Zr(x)Ti(1-x))O(3) and Pb[(Sb(1/3)Mn(2/3))(0.05)Zr(x)Ti (0.95-x)]O(3) solid solutions, were investigated. Relations between temperature coefficients of epsilon(33)(T ), S(11)(E), and S(11) (P) were theoretically derived; a discrepancy was found between theoretical relations and experimental results. On the basis of the observed discrepancy, it is proposed that some extrinsic effects arising from the motion of interphase boundaries between the tetragonal and the rhombohedral phases which exist in grains contribute to values of both elastic compliances.

  1. Comparison of effective relative dielectric permittivities obtained by three independent ways for CeO2-Sm2O3 films prepared by EB-PVD (+IBAD) techniques

    International Nuclear Information System (INIS)

    Kundracik, F.; Neilinger, P.; Hartmanova, M.; Nadazdy, V.; Mansilla, C.

    2011-01-01

    Ceria, as material with relatively high dielectric permittivity, ε r , and ability to form films on the Si substrate, is a candidate for the gate dielectrics in the MOS devices. Doping with suitable e.g. trivalent rare earth oxides and suitable treatment after deposition (preparation) can improve their properties, e.g. ionic conductivity, dielectric permittivity and mechanical hardness. In this work, the dielectric properties of CeO 2 + Sm 2 O 3 films prepared by electron beam physical vapour deposition (EB-PVD) and some of them simultaneously also by the Ar + ionic beam assisted deposition (IBAD) techniques are analysed. (authors)

  2. Completeness relations for the electromagnetic modes of a cylindrical fibre with a radially dependent dielectric and magnetic permittivity and conductivity

    NARCIS (Netherlands)

    Hoenders, B.J.

    1986-01-01

    We consider an infinitely long conducting cylinder whose dielectric and magnetic permittivity and conductivity are functions of the distance from a point inside the cylinder to its axis. It is shown that the r-dependent part of the set of electromagnetic modes associated with such a cylinder is

  3. Nanodielectrics with giant permittivity

    Indian Academy of Sciences (India)

    Following the prediction, during the last couple of years we have investigated the effect of giant permittivity in one-dimensional systems of conventional metals and conjugated polymer chains. In this article, we have tried to summarize the works on giant permittivity and finally the fabrication of nanocapacitor using metal ...

  4. Excess molar volume along with viscosity, refractive index and relative permittivity for binary mixtures of exo-tetrahydrodicyclopentadiene with four octane isomers

    International Nuclear Information System (INIS)

    Yue, Lei; Qin, Xiaomei; Wu, Xi; Xu, Li; Guo, Yongsheng; Fang, Wenjun

    2015-01-01

    Highlights: • Binary mixtures of JP-10 with octane isomers are studied as model hydrocarbon fuels. • Density, viscosity, refractive index and relative permittivity are determined. • Excess molar volumes and viscosity deviations are calculated and correlated. - Abstract: The fundamental physical properties including density, viscosity, refractive index and relative permittivity, have been measured for binary mixtures of exo-tetrahydrodicyclopentadiene (JP-10) with four octane isomers (n-octane, 3-methylheptane, 2,4-dimethylhexane and 2,2,4-trimethylpentane) over the whole composition range at temperatures T = (293.15 to 313.15) K and pressure p = 0.1 MPa. The values of excess molar volume (V m E ), viscosity deviation (Δη), refractive index deviation (Δn D ) and relative permittivity deviation (Δε r ) are then calculated. All of the values of V m E and Δη are observed to be negative, while those of Δn D and Δε r are close to zero. The effects of temperature and composition on the variation of V m E values are discussed. The negative values of V m E and Δη are conductive to high-density and low-resistance of fuels, which is favorable for the design and preparation of advanced hydrocarbon fuels

  5. Nanodielectrics with giant permittivity

    Indian Academy of Sciences (India)

    Wintec

    Department of Materials Science, Indian Association for the Cultivation of Science, ... In particular, ... 10. ) permittivity value in an assembly of ultra fine silver metal particles as .... Chang S, Doremus R H, Ajayan P M and Siegel R W 2000.

  6. Algorithmic Relative Complexity

    Directory of Open Access Journals (Sweden)

    Daniele Cerra

    2011-04-01

    Full Text Available Information content and compression are tightly related concepts that can be addressed through both classical and algorithmic information theories, on the basis of Shannon entropy and Kolmogorov complexity, respectively. The definition of several entities in Kolmogorov’s framework relies upon ideas from classical information theory, and these two approaches share many common traits. In this work, we expand the relations between these two frameworks by introducing algorithmic cross-complexity and relative complexity, counterparts of the cross-entropy and relative entropy (or Kullback-Leibler divergence found in Shannon’s framework. We define the cross-complexity of an object x with respect to another object y as the amount of computational resources needed to specify x in terms of y, and the complexity of x related to y as the compression power which is lost when adopting such a description for x, compared to the shortest representation of x. Properties of analogous quantities in classical information theory hold for these new concepts. As these notions are incomputable, a suitable approximation based upon data compression is derived to enable the application to real data, yielding a divergence measure applicable to any pair of strings. Example applications are outlined, involving authorship attribution and satellite image classification, as well as a comparison to similar established techniques.

  7. Complex manifolds in relativity

    International Nuclear Information System (INIS)

    Flaherty, E.J. Jr.

    1975-01-01

    Complex manifold theory is applied to the study of certain problems in general relativity. The first half of the work is devoted to the mathematical theory of complex manifold. Then a brief review of general relativity is given. It is shown that any spacetime admits locally an almost Hermitian structure, suitably modified to be compatible with the indefinite metric of spacetime. This structure is integrable if and only if the spacetime admits two geodesic and shearfree null congruences, thus in particular if the spacetime is type D vacuum or electrified. The structure is ''half-integrable'' in a suitable sense if and only if the spacetime admits one geodesic and shearfree null congruence, thus in particular for all algebraically special vacuum spacetimes. Conditions for the modified Hermitian spacetime to be Kahlerian are presented. The most general metric for such a modified Kahlerian spacetime is found. It is shown that the type D vacuum and electrified spacetimes are conformally related to modified Kahlerian spacetimes by a generally complex conformal factor. These latter are shown to possess a very rich structure, including the existence of Killing tensors and Killing vectors. A new ''explanation'' of Newman's complex coordinate transformations is given. It is felt to be superior to previous ''explanations'' on several counts. For example, a physical interpretation in terms of a symmetry group is given. The existence of new complex coordinate transformations is established: Nt is shown that any type D vacuum spacetime is obtainable from either Schwarzschild spacetime or ''C'' spacetime by a complex coordinate transformation. Finally, some related topics are discussed and areas for future work are outlined. (Diss. Abstr. Int., B)

  8. Printed circuit board permittivity measurement using waveguide and resonator rings

    NARCIS (Netherlands)

    Op 't Land, Sjoerd; Tereshchenko, O.V.; Ramdani, Mohamed; Leferink, Frank Bernardus Johannes; Perdriau, Richard

    2014-01-01

    Knowing the frequency dependent complex permittivity of Printed Circuit Board (PCB) substrates is important in modern electronics. In this paper, two methods for measuring the permittivity are applied to the same Flame Resistant (FR4) substrate and the results are compared. The reference measurement

  9. Generalized dielectric permittivity tensor

    International Nuclear Information System (INIS)

    Borzdov, G.N.; Barkovskii, L.M.; Fedorov, F.I.

    1986-01-01

    The authors deal with the question of what is to be done with the formalism of the electrodynamics of dispersive media based on the introduction of dielectric-permittivity tensors for purely harmonic fields when Voigt waves and waves of more general form exist. An attempt is made to broaden and generalize the formalism to take into account dispersion of waves of the given type. In dispersive media, the polarization, magnetization, and conduction current-density vectors of point and time are determined by the values of the electromagnetic field vectors in the vicinity of this point (spatial dispersion) in the preceding instants of time (time dispersion). The dielectric-permittivity tensor and other tensors of electrodynamic parameters of the medium are introduced in terms of a set of evolution operators and not the set of harmonic function. It is noted that a magnetic-permeability tensor and an elastic-modulus tensor may be introduced for an acoustic field in dispersive anisotropic media with coupling equations of general form

  10. Test plan for prototype dielectric permittivity sensor

    International Nuclear Information System (INIS)

    Pfeifer, M.C.

    1993-07-01

    The digface characterization project funded by the Buried Waste Integrated Demonstration (BWID) is designed to test a new method of monitoring hazardous conditions during the remediation at waste sites. Often on a large scale, the exact cause of each anomaly is difficult to determine and ambiguities remain in the characterization of a site. The digface characterization concept is designed to alleviate some of this uncertainty by creating systems that monitor small volumes of soil and detect anomalous areas during remediation before they are encountered. The goal of the digface characterization demonstration is to detect changes in the physical properties from one volume to another and relate these changes in physical properties to changes in the level of contamination. Dielectric permittivity mapping is a method that might prove useful in digface characterization. In this project, the role of a dielectric permittivity monitoring device is under investigation. This project addresses two issues: what are the optimal means of mapping dielectric permittivity contrasts and what types of targets can be detected using dielectric permittivity mapping

  11. Longitudinal permittivity of a toroidal plasma near rational surfaces

    International Nuclear Information System (INIS)

    Nekrasov, F.M.

    1990-01-01

    A quite simple analytical formula for longitudinal permittivity, suitable for numerical processing on a computer, is determined. On the basis of a Fourier representation a poloidal angle a compact expression for the imaginary part of longitudinal permittivity near rational surfaces (m+nq=0) at an arbitrary relation between the bounce frequency and excited wave frequency is determined. A strongly magnetized collisionless plasma in the weak toroidality approximation is considered

  12. Experimental measurements and numerical simulation of permittivity and permeability of Teflon in X band

    Directory of Open Access Journals (Sweden)

    Adriano Luiz de Paula

    2011-01-01

    Full Text Available Recognizing the importance of an adequate characterization of radar absorbing materials, and consequently their development, the present study aims to contribute for the establishment and validation of experimental determination and numerical simulation of electromagnetic materials complex permittivity and permeability, using a Teflon® sample. The present paper branches out into two related topics. The first one is concerned about the implementation of a computational modeling to predict the behavior of electromagnetic materials in confined environment by using electromagnetic three-dimensional simulation. The second topic re-examines the Nicolson-Ross-Weir mathematical model to retrieve the constitutive parameters (complex permittivity and permeability of a homogeneous sample (Teflon®, from scattering coefficient measurements. The experimental and simulated results show a good convergence that guarantees the application of the used methodologies for the characterization of different radar absorbing materials samples.

  13. Influence of deposition conditions on electrical and mechanical properties of Sm2O3-doped CeO2 thin films prepared by EB-PVD (+IBAD) methods. Part 1: Effective relative permittivity

    Science.gov (United States)

    Hartmanová, Mária; Nádaždy, Vojtech; Kundracik, František; Mansilla, Catina

    2013-03-01

    Study is devoted to the effective relative permittivity ɛr of CeO2 + x. Sm2O3 thin films prepared by electron-beam physical vapour deposition and ionic beam-assisted deposition methods; ɛr was investigated by three independent ways from the bulk parallel capacitance Cp, impedance capacitance Cimp, and accumulation capacitance Cacc in dependence on the deposition conditions (deposition temperature, dopant amount x and Ar+ ion bombardment during the film deposition) used. Investigations were performed using impedance spectroscopy, capacitance-voltage and current-voltage characteristics as well as deep level transient spectroscopy. Results obtained are described and discussed.

  14. The influence of the relative thermal expansion and electric permittivity on phase transitions in the perovskite-type bidimensional layered NH3(CH2)3NH3CdBr4 compound

    Science.gov (United States)

    Staśkiewicz, Beata; Staśkiewicz, Anna

    2017-07-01

    Hydrothermal method has been used to synthesized the layered hybrid compound NH3(CH2)3NH3CdBr4 of perovskite architecture. Structural, dielectric and dilatometric properties of the compound have been analyzed. Negative thermal expansion (NTE) effect in the direction perpendicular to the perovskite plane as well as an unusual phase sequence have been reported based on X-ray diffraction analysis. Electric permittivity measurements evidenced the phase transitions at Tc1=326/328 K and Tc2=368/369 K. Relative linear expansion measurements almost confirmed these temperatures of phase transitions. Anomalies of electric permittivity and expansion behavior connected with the phase transitions are detected at practically the same temperatures as those observed earlier in differential scanning calorimetry (DSC), infrared (IR), far infrared (FIR) and Raman spectroscopy studies. Mechanism of the phase transitions is explained. Relative linear expansion study was prototype to estimate critical exponent value β for continuous phase transition at Tc1. It has been inferred that there is a strong interplay between the distortion of the inorganic network, those hydrogen bonds and the intermolecular interactions of the organic component.

  15. Artificial high effective permittivity medium in a SIW filled with metallic cylinders

    Science.gov (United States)

    Vicent, G.; Bronchalo, E.; Coves, A.; Torregrosa, G.

    2018-02-01

    A new topology of step-impedance band-pass filters in Substrate Integrated Waveguide (SIW) technology has been recently demonstrated in which low effective permittivity regions have been achieved by removing part of the substrate material and then shielding the perforated structure. Alternatively, in this work a new way to obtain an increased relative permittivity in the guiding region is proposed by periodically inserting metallic inclusions. This paper shows the results of a systematic study of the effective permittivity obtained in this way in a SIW in order to synthesize a higher effective permittivity, which can be used in the filter design.

  16. Pseudo-complex general relativity

    CERN Document Server

    Hess, Peter O; Greiner, Walter

    2016-01-01

    This volume presents an pseudo-complex extension of General Relativity which addresses these issues and presents proposals for experimental examinations in strong fields near a large mass. General Relativity is a beautiful and well tested theory of gravitation. Nevertheless, it implies conceptual problems like the creation of singularities (Black Holes) as a result of the collapse of large masses, or the appearance of event horizons which exclude parts of the space-time from the observation of external observers. The mathematical and geometrical foundations of this extension are displayed in detail, and applications including orbits and accretion disks around large central masses, neutron stars or cosmological models are introduced. Calculations both for classical and extended applications are often executed in the form of problems with extensive solutions, which makes this volume also a valuable resource for any student of General Relativity.

  17. Functional silicone copolymers and elastomers with high dielectric permittivity

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Daugaard, Anders Egede; Hvilsted, Søren

    Dielectric elastomers (DEs) are a new and promising transducer technology and are often referred to as ‘artificial muscles’, due to their ability to undergo large deformations when stimulated by electric fields. DEs consist of a soft and thin elastomeric film sandwiched between compliant electrodes......, thereby forming a capacitor [1]. Silicone elastomers are one of the most used materials for DEs due to their high efficiency, fast response times and low viscous losses. The major disadvantage of silicone elastomers is that they possess relatively low dielectric permittivity, which means that a high...... electrical field is necessary to operate the DE. The necessary electrical field can be lowered by creating silicone elastomers with higher dielectric permittivity, i.e. with a higher energy density.The aim of this work is to create new and improved silicone elastomers with high dielectric permittivity...

  18. Glycerol as high-permittivity liquid filler in dielectric silicone elastomers

    DEFF Research Database (Denmark)

    Mazurek, Piotr Stanislaw; Yu, Liyun; Skov, Anne Ladegaard

    of the composite. In combination with very low cost and easy preparation, the two property enhancements lead to a very attractive dielectric elastomer material. Experimental permittivity data are compared to various theoretical models that predict relative-permittivity changes as a function of filler loading...

  19. Influence of permittivity on gradient force exerted on Mie spheres.

    Science.gov (United States)

    Chen, Jun; Li, Kaikai; Li, Xiao

    2018-04-01

    In optical trapping, whether a particle could be stably trapped into the focus region greatly depends on the strength of the gradient force. Individual theoretical study on gradient force exerted on a Mie particle is rare because the mathematical separation of the gradient force and the scattering force in the Mie regime is difficult. Based on the recent forces separation work by Du et al. [Sci. Rep.7, 18042 (2017)SRCEC32045-232210.1038/s41598-017-17874-1], we investigate the influence of permittivity (an important macroscopic physical quantity) on the gradient force exerted on a Mie particle by cooperating numerical calculation using fast Fourier transform and analytical analysis using multipole expansion. It is revealed that gradient forces exerted on small spheres are mainly determined by the electric dipole moment except for certain permittivity with which the real part of polarizability of the electric dipole approaches zero, and gradient forces exerted on larger spheres are complex because of the superposition of the multipole moments. The classification of permittivity corresponding to different varying tendencies of gradient forces exerted on small spheres or larger Mie particles are illustrated. Absorption of particles favors the trapping of small spheres by gradient force, while it is bad for the trapping of larger particles. Moreover, the absolute values of the maximal gradient forces exerted on larger Mie particles decline greatly versus the varied imaginary part of permittivity. This work provides elaborate investigation on the different varying tendencies of gradient forces versus permittivity, which favors more accurate and free optical trapping.

  20. Simultaneous reconstruction of permittivity and conductivity using multi-frequency admittance measurement in electrical capacitance tomography

    International Nuclear Information System (INIS)

    Zhang, Maomao; Soleimani, Manuchehr

    2016-01-01

    Electrical capacitance tomography (ECT) is an imaging method mainly capable of reconstructing dielectric permittivity. Generally, the reactance part of complex admittance is measured in a selected frequency. This paper presents for the first time an in depth and systematic analysis of complex admittance data for simultaneous reconstruction of both electrical conductivity and dielectric permittivity. A complex-valued forward model, Jacobian matrix and inverse solution are developed in the time harmonic excitation mode to allow for multi-frequency measurements. Realistic noise models are used to evaluate the performance of complex admittance ECT in a range of excitation frequencies. This paper demonstrates far greater potential for ECT as a versatile imaging tool through novel analysis of complex admittance imaging using a dual conductivity permittivity inversion method. The paper demonstrates that various classes of contactless capacitance based measurement devices can be analysed through complex multi-frequency ECT. (paper)

  1. Effective conductivity and permittivity of unsaturated porous materials in the frequency range 1 mHz–1GHz

    Science.gov (United States)

    Revil, A

    2013-01-01

    A model combining low-frequency complex conductivity and high-frequency permittivity is developed in the frequency range from 1 mHz to 1 GHz. The low-frequency conductivity depends on pore water and surface conductivities. Surface conductivity is controlled by the electrical diffuse layer, the outer component of the electrical double layer coating the surface of the minerals. The frequency dependence of the effective quadrature conductivity shows three domains. Below a critical frequency fp, which depends on the dynamic pore throat size Λ, the quadrature conductivity is frequency dependent. Between fp and a second critical frequency fd, the quadrature conductivity is generally well described by a plateau when clay minerals are present in the material. Clay-free porous materials with a narrow grain size distribution are described by a Cole-Cole model. The characteristic frequency fd controls the transition between double layer polarization and the effect of the high-frequency permittivity of the material. The Maxwell-Wagner polarization is found to be relatively negligible. For a broad range of frequencies below 1 MHz, the effective permittivity exhibits a strong dependence with the cation exchange capacity and the specific surface area. At high frequency, above the critical frequency fd, the effective permittivity reaches a high-frequency asymptotic limit that is controlled by the two Archie's exponents m and n like the low-frequency electrical conductivity. The unified model is compared with various data sets from the literature and is able to explain fairly well a broad number of observations with a very small number of textural and electrochemical parameters. It could be therefore used to interpret induced polarization, induction-based electromagnetic methods, and ground penetrating radar data to characterize the vadose zone. PMID:23576823

  2. Superspace de Rham complex and relative cohomology

    Energy Technology Data Exchange (ETDEWEB)

    III, William D. Linch; Randall, Stephen [Center for String and Particle Theory,Department of Physics, University of Maryland at College Park,College Park, MD 20742-4111 (United States)

    2015-09-28

    We investigate the super-de Rham complex of five-dimensional superforms with N=1 supersymmetry. By introducing a free supercommutative algebra of auxiliary variables, we show that this complex is equivalent to the Chevalley-Eilenberg complex of the translation supergroup with values in superfields. Each cocycle of this complex is defined by a Lorentz- and iso-spin-irreducible superfield subject to a set of constraints. Restricting to constant coefficients results in a subcomplex in which components of the cocycles are coboundaries while the constraints on the defining superfields span the cohomology. This reduces the computation of all of the superspace Bianchi identities to a single linear algebra problem the solution of which implies new features not present in the standard four-dimensional, N=1 complex. These include splitting/joining in the complex and the existence of cocycles that do not correspond to irreducible supermultiplets of closed differential forms. Interpreting the five-dimensional de Rham complex as arising from dimensional reduction from the six-dimensional complex, we find a second five-dimensional complex associated to the relative de Rham complex of the embedding of the latter in the former. This gives rise to a second source of closed differential forms previously attributed to the phenomenon called “Weyl triviality”.

  3. Effective permittivity of finite inhomogeneous objects

    NARCIS (Netherlands)

    Raghunathan, S.B.; Budko, N.V.

    2010-01-01

    A generalization of the S-parameter retrieval method for finite three-dimensional inhomogeneous objects under arbitrary illumination and observation conditions is presented. The effective permittivity of such objects may be rigorously defined as a solution of a nonlinear inverse scattering problem.

  4. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

    International Nuclear Information System (INIS)

    Farace, Paolo; Antolini, Renzo; Pontalti, Rolando; Cristoforetti, Luca; Scarpa, Marina

    1997-01-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

  5. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Farace, Paolo; Antolini, Renzo [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy); Pontalti, Rolando; Cristoforetti, Luca [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Scarpa, Marina [Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy)

    1997-11-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

  6. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning.

    Science.gov (United States)

    Farace, P; Pontalti, R; Cristoforetti, L; Antolini, R; Scarpa, M

    1997-11-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning.

  7. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Farace, Paolo; Antolini, Renzo [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy); Pontalti, Rolando; Cristoforetti, Luca [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Scarpa, Marina [Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy)

    1997-11-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

  8. Multiband Negative Permittivity Metamaterials and Absorbers

    Directory of Open Access Journals (Sweden)

    Yiran Tian

    2013-01-01

    Full Text Available Design and characteristics of multiband negative permittivity metamaterial and its absorber configuration are presented in this paper. The proposed multiband metamaterial is composed of a novel multibranch resonator which can possess four electric resonance frequencies. It is shown that, by controlling the length of the main branches of such resonator, the resonant frequencies and corresponding absorbing bands of metamaterial absorber can be shifted in a large frequency band.

  9. Identifying modular relations in complex brain networks

    DEFF Research Database (Denmark)

    Andersen, Kasper Winther; Mørup, Morten; Siebner, Hartwig

    2012-01-01

    We evaluate the infinite relational model (IRM) against two simpler alternative nonparametric Bayesian models for identifying structures in multi subject brain networks. The models are evaluated for their ability to predict new data and infer reproducible structures. Prediction and reproducibility...... and obtains comparable reproducibility and predictability. For resting state functional magnetic resonance imaging data from 30 healthy controls the IRM model is also superior to the two simpler alternatives, suggesting that brain networks indeed exhibit universal complex relational structure...

  10. The complex relation between morality and empathy.

    Science.gov (United States)

    Decety, Jean; Cowell, Jason M

    2014-07-01

    Morality and empathy are fundamental components of human nature across cultures. However, the wealth of empirical findings from developmental, behavioral, and social neuroscience demonstrates a complex relation between morality and empathy. At times, empathy guides moral judgment, yet other times empathy can interfere with it. To better understand such relations, we propose abandoning the catchall term of empathy in favor of more precise concepts, such as emotional sharing, empathic concern, and affective perspective-taking. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Ionic conductivity and dielectric permittivity of polymer electrolyte plasticized with polyethylene glycol

    Science.gov (United States)

    Das, S.; Ghosh, A.

    2016-05-01

    We have studied ionic conductivity and dielectric permittivity of PEO-LiClO4 solid polymer electrolyte plasticized with polyethylene glycol (PEG). The temperature dependence of the ionic conductivity has been well interpreted using Vogel-Tamman-Fulcher equation. The maximum dielectric constant is observed for 30 wt. % of PEG content. To get further insights into the ion dynamics, the complex dielectric permittivity has been studied with Havriliak-Negami function. The variation of relaxation time with inverse temperature obtained from HN formalism follows VTF nature.

  12. Direct 2-D reconstructions of conductivity and permittivity from EIT data on a human chest.

    Science.gov (United States)

    Herrera, Claudia N L; Vallejo, Miguel F M; Mueller, Jennifer L; Lima, Raul G

    2015-01-01

    A novel direct D-bar reconstruction algorithm is presented for reconstructing a complex conductivity distribution from 2-D EIT data. The method is applied to simulated data and archival human chest data. Permittivity reconstructions with the aforementioned method and conductivity reconstructions with the previously existing nonlinear D-bar method for real-valued conductivities depicting ventilation and perfusion in the human chest are presented. This constitutes the first fully nonlinear D-bar reconstructions of human chest data and the first D-bar permittivity reconstructions of experimental data. The results of the human chest data reconstructions are compared on a circular domain versus a chest-shaped domain.

  13. Simultaneous measurement of hysteresis in capillary pressure and electric permittivity for multiphase flow through porous media

    NARCIS (Netherlands)

    Plug, W.J.; Slob, E.C.; Bruining, J.; Moreno Tirado, L.M.

    2007-01-01

    We present a tool that simultaneously measures the complex permittivity and the capillary pressure characteristics for multiphase flow. The sample holder is a parallel plate capacitor. A precision component analyzer is used to measure the impedance amplitude and phase angle as a function of

  14. Study on the Microwave Permittivity of Single-Walled Carbon Nanotube

    Science.gov (United States)

    Liu, Xiaolai; Zhao, Donglin

    2009-01-01

    In this article, we studied the microwave permittivity of the complex of the single-walled carbon nanotube and paraffin in 2-18GHz. In the range, the dielectric loss of single-walled carbon nanotube is higher, and the real part and the imaginary part of the dielectric constant decrease with the increase of frequency, and the dielectric constant…

  15. Determination of permittivity of pulses and cereals using metamaterial split ring resonator

    Science.gov (United States)

    Chakyar, Sreedevi P.; Sikha Simon, K.; Murali, Aathira; Shanto T., A.; Andrews, Jolly; Joseph V., P.

    2017-06-01

    Relative permittivity of wide variety of pulses and cereals are precisely determined with the help of metamaterial Split Ring Resonator (SRR) operating at microwave frequencies using a simple extraction procedure. The unknown permittivity of food samples in powder form are evaluated from a calibration curve drawn between the dielectric constant of some standard samples and LC resonant frequency of SRR test probe with the sample placed over it. The experimental setup consists of SRR test probe arranged between transmitting and receiving probes connected to a vector network analyzer. Unknown relative permittivity of the sample is obtained by placing it on the SRR surface and is evaluated from the calibration curve which is found to be in good agreement with the expected standard values. The possible applications of this sensitive and easy technique are analyzed in the field of food preservation, quality checking, adulteration etc.

  16. INVESTIGATION OF THE FREQUENCY-TEMPERATURE RELATIONSHIP OF THE DIELECTRIC PERMITTIVITY OF THE PZT PIEZOCERAMICS IN THE LOW FREQUENCY RANGE

    Directory of Open Access Journals (Sweden)

    A. I. ZOLOTAREVSKIY

    2018-05-01

    Full Text Available Purpose. To investigate the frequency-temperature relationship of the dielectric permittivity of PZT piezoceramics in the low frequency range. Methodology. To obtain the frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics, a technique was used to determine the capacitance of the capacitor, between which plates the sample was placed. The value of the dielectric permittivity of the sample was calculated from the capacitor capacitance obtained. Findings. The frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics in the low frequency range has been obtained by the authors. The dielectric permittivity is not practically related to the frequency of the alternating voltage at a low temperature, with increasing in temperature its value increases and frequency relationship is observed. The temperature relationship of the dielectric permittivity of the PZT piezoceramics is satisfactorily described by the exponential functional dependence in the low-temperature range. The activation energy of the PZT piezoceramics polarization is determined from the graph of the dependence of the logarithm of the dielectric permittivity upon the inverse temperature. Different values of the activation energy for the two temperature regions prove on the existence of different mechanisms of the PZT piezoceramics polarization in the temperature range being investigated. Originality. The authors investigated the frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics in the low-frequency range. It is established that the temperature relationship of the dielectric permittivity of the PZT piezoceramics is satisfactorily described by an exponential functional relationship in the lowtemperature range. The activation energy of polarization is determined for two temperature sections. Practical value. The research results can be used to study the mechanism of polarization of

  17. Large electrical manipulation of permittivity in BaTiO3 and Pb(Zr,Ti)O3 bimorph heterostructure

    International Nuclear Information System (INIS)

    Ci, Penghong; Liu, Guoxi; Dong, Shuxiang; Zhang, Li

    2014-01-01

    We report a strain-mediated electric field manipulation of permittivity in BaTiO 3 (barium titanate, BT) ceramic by a Pb(Zr,Ti)O 3 (PZT) bimorph. This BT/PZT heterostructure exhibited a relatively large permittivity tunability of BT up to ±10% in a wide frequency range under an electric field of ±4 kV/cm applied to the PZT bimorph. The permittivity tunability is attributed to the strain in BT produced by the PZT bimorph. Calculations of the relationship between permittivity and applied electric field were developed, and corresponded well with measurements. The BT/PZT heterostructure has potential for applications in broadband field tunable smart electronic devices.

  18. Capillary pressure as a unique function of electric permittivity and water saturation

    NARCIS (Netherlands)

    Plug, W.J.; Slob, E.; Van Turnhout, J.; Bruining, J.

    2007-01-01

    The relation between capillary pressure (Pc) and interfacial area has been investigated by measuring Pc and the electric permittivity at 100 kHz simultaneously as function of the water saturation, (Sw). Drainage and imbibition experiments have been conducted for sand-distilled water-gas (CO2/N2)

  19. Preliminary Broadband Measurements of Dielectric Permittivity of Planetary Regolith Analog Materials Using a Coaxial Airline

    Science.gov (United States)

    Boivin, A.; Tsai, C. A.; Ghent, R. R.; Daly, M. G.

    2014-12-01

    When considering radar observations of airless bodies containing regolith, the radar backscatter coefficient is dependent upon the complex dielectric permittivity of the regolith materials. In many current applications of imaging radar data, uncertainty in the dielectric permittivity precludes quantitative estimates of such important parameters as regolith thickness and depth to buried features (e.g., lava flows on the Aristarchus Plateau on the Moon and the flows that surround the Quetzalpetlatl Corona on Venus). For asteroids, radar is an important tool for detecting and characterizing regoliths. Many previous measurements of the real and/or complex parts of the dielectric permittivity have been made, particularly for the Moon (on both Apollo samples and regolith analogues). However, no studies to date have systematically explored the relationship between permittivity and the various mineralogical components such as presence of FeO and TiO2. For lunar materials, the presence of the mineral ilmenite (FeTiO3), which contains equal portions FeO and TiO2, is thought to be the dominant factor controlling the loss tangent (tanδ, the ratio of the imaginary and real components of the dielectric permittivity). Ilmenite, however, is not the only mineral to contain iron in the lunar soil and our understanding of the effect of iron on the loss tangent is insufficient. Beyond the Moon, little is known about the effects on permittivity of carbonaceous materials. This is particularly relevant for missions to asteroids, such as the OSIRIS-REx mission to (101955) Bennu, a carbonaceous asteroid whose regolith composition is largely unknown. Here we present preliminary broadband (300 Mhz to 14 GHz) measurements on materials intended as planetary regolith analogs. Our ultimate goal is to establish a database of the effects of a wide range mineralogical components on dielectric permittivity, in support of the OSIRIS REx mission and ongoing Earth-based radar investigation of the Moon

  20. An X-band waveguide measurement technique for the accurate characterization of materials with low dielectric loss permittivity

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Kenneth W., E-mail: kenneth.allen@gtri.gatech.edu; Scott, Mark M.; Reid, David R.; Bean, Jeffrey A.; Ellis, Jeremy D.; Morris, Andrew P.; Marsh, Jeramy M. [Advanced Concepts Laboratory, Georgia Tech Research Institute, Atlanta, Georgia 30318 (United States)

    2016-05-15

    In this work, we present a new X-band waveguide (WR90) measurement method that permits the broadband characterization of the complex permittivity for low dielectric loss tangent material specimens with improved accuracy. An electrically long polypropylene specimen that partially fills the cross-section is inserted into the waveguide and the transmitted scattering parameter (S{sub 21}) is measured. The extraction method relies on computational electromagnetic simulations, coupled with a genetic algorithm, to match the experimental S{sub 21} measurement. The sensitivity of the technique to sample length was explored by simulating specimen lengths from 2.54 to 15.24 cm, in 2.54 cm increments. Analysis of our simulated data predicts the technique will have the sensitivity to measure loss tangent values on the order of 10{sup −3} for materials such as polymers with relatively low real permittivity values. The ability to accurately characterize low-loss dielectric material specimens of polypropylene is demonstrated experimentally. The method was validated by excellent agreement with a free-space focused-beam system measurement of a polypropylene sheet. This technique provides the material measurement community with the ability to accurately extract material properties of low-loss material specimen over the entire X-band range. This technique could easily be extended to other frequency bands.

  1. [Cancer-vitamins-minerals: Complex relation].

    Science.gov (United States)

    Adrianza de Baptista, Gertrudis; Murillo Melo, Carolain

    2014-12-01

    Since nutrition can influence the process of carcinogenesis, this study's objectives are to review the relationship between nutrition and cancer from the point of view of the role of micronutrients in the treatment of cancer patients, and to get to know the deficit relationship and the excess of micronutrients, with the etiology and cancer treatment. At the same time the patient's weight loss relates, among other things, to the type of cancerous tumor, its location, stage thereof, reason for which it may be associated with the deficiency of macro and micronutrients as from psychogenic, anorectics and mal-absorption effects or with mechanical effects as obstruction, among other toxic effects that are common in the treatment of cancer. Hence, the importance that the nutrition expert must have in making an adequate overall nutritional evaluation that allows the nutritional diagnosis, in studying the dietary patterns, to determine the toxic effects of the antineoplastic treatment in order to handle the treatment's timing excellence, symptoms and signs, and thus act effectively optiimizing the patient's life quality, and therewith his/her survival. There are controversies as to which specific dietary factors are related to cancer etiology and the results of studies on metabolic factors, and therefore, the relationship Cancer-Nutrition is quiet complex.

  2. Accuracy enhancement of laser induced breakdown spectra using permittivity and size optimized plasma confinement rings.

    Science.gov (United States)

    Li, An; Guo, Shuai; Wazir, Nasrullah; Chai, Ke; Liang, Liang; Zhang, Min; Hao, Yan; Nan, Pengfei; Liu, Ruibin

    2017-10-30

    The inevitable problems in laser induced breakdown spectroscopy are matrix effect and statistical fluctuation of the spectral signal, which can be partly avoided by utilizing a proper confined unit. The dependences of spectral signal enhancement on relative permittivity were studied by varying materials to confine the plasma, which include polytetrafluoroethylene(PTFE), nylon/dacron, silicagel, and nitrile-butadiene rubber (NBR) with the relative permittivity 2.2, ~3.3, 3.6, 8~13, 15~22. We found that higher relative permittivity rings induce stronger enhancement ability, which restricts the energy dissipation of plasma better and due to the reflected electromagnetic wave from the wall of different materials, the electromagnetic field of plasma can be well confined and makes the distribution of plasma more orderly. The spectral intensities of the characteristic lines Si I 243.5 nm and Si I 263.1 nm increased approximately 2 times with relative permittivity values from 2.2 to ~20. The size dependent enhancement of PTFE was further checked and the maximum gain was realized by using a confinement ring with a diameter size of 5 mm and a height of 3 mm (D5mmH3mm), and the rings with D2mmH1mm and D3mmH2mm also show higher enhancement factor. In view of peak shift, peak lost and accidental peaks in the obtained spectra were properly treated in data progressing; the spectral fluctuation decreased drastically for various materials with different relative permittivities as confined units, which means the core of plasma is stabilized, attributing to the confinement effect. Furthermore, the quantitative analysis in coal shows wonderful results-the prediction fitting coefficient R 2 reaches 0.98 for ash and 0.99 for both volatile and carbon.

  3. Permittivity and density of the systems (monoglyme, diglyme, triglyme, or tetraglyme + n-heptane) at several temperatures

    International Nuclear Information System (INIS)

    Riadigos, C.F.; Iglesias, R.; Rivas, M.A.; Iglesias, T.P.

    2011-01-01

    Relative permittivity and density on mixing at atmospheric pressure and temperatures from (288.15 to 308.15) K and atmospheric pressure have been measured over the entire composition range of mixing for {CH 3 O(CH 2 CH 2 O) m CH 3 with m = 1, 2, 3, 4 (also called monoglyme, diglyme, triglyme, or tetraglyme) + n-heptane}. The permittivity values were fitted as a function of the volume fraction and temperature to a logarithmic equation. The excess permittivity is calculated considering a definition that has been recently established in terms of the volume fraction. Excess molar volumes on mixing for the above systems have also been calculated. The density and excess molar volumes were fitted as a function of both mole fraction and temperature to a polynomial equation. The temperature dependence of derived magnitudes, (∂V m E /∂T) P,x and (∂H m E /∂P) T,x , was computed, given their importance in the study of specific molecular interactions. The experimental values of permittivity have been compared to those estimated by usual models of literature and the results indicate that the predictions are better when the volume change on mixing is incorporated in calculations. From the values of permittivity and density on mixing the dipole moment for tetraglyme was calculated. The work concludes with an interpretation of the sign of excess permittivity and its behaviour with temperature and that of excess molar volume.

  4. A microcontroller-based microwave free-space measurement system for permittivity determination of lossy liquid materials.

    Science.gov (United States)

    Hasar, U C

    2009-05-01

    A microcontroller-based noncontact and nondestructive microwave free-space measurement system for real-time and dynamic determination of complex permittivity of lossy liquid materials has been proposed. The system is comprised of two main sections--microwave and electronic. While the microwave section provides for measuring only the amplitudes of reflection coefficients, the electronic section processes these data and determines the complex permittivity using a general purpose microcontroller. The proposed method eliminates elaborate liquid sample holder preparation and only requires microwave components to perform reflection measurements from one side of the holder. In addition, it explicitly determines the permittivity of lossy liquid samples from reflection measurements at different frequencies without any knowledge on sample thickness. In order to reduce systematic errors in the system, we propose a simple calibration technique, which employs simple and readily available standards. The measurement system can be a good candidate for industrial-based applications.

  5. On the Huygens principle for bianisotropic mediums with symmetric permittivity and permeability dyadics

    Energy Technology Data Exchange (ETDEWEB)

    Faryad, Muhammad, E-mail: muhammad.faryad@lums.edu.pk [Department of Physics, Lahore University of Management Sciences, Lahore 54792 (Pakistan); Lakhtakia, Akhlesh [Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2017-02-19

    Mathematical statements of the Huygens principle relate the electric and magnetic field phasors at an arbitrary location in a source-free region enclosed by a surface to the tangential components of the electric and magnetic field phasors over that surface, via the dyadic Green functions applicable to the linear homogeneous medium occupying that region. We have mathematically formulated the Huygens principle for the electric and magnetic field phasors when the permittivity and permeability dyadics of the medium are symmetric, the symmetric parts of the two magnetoelectric dyadics of the medium are negative of each other, and both magnetoelectric dyadics also contain anti-symmetric terms. We have also formulated the Huygens principle for the electric (resp. magnetic) field phasor in a medium whose permittivity (resp. permeability) is scalar, the permeability (resp. permittivity) is symmetric, the symmetric parts of the two magnetoelectric dyadics reduce to dissimilar scalars, and anti-symmetric parts of the two magnetoelectric dyadics are identical. - Highlights: • The Huygens principle was formulated for bianistropic mediums when the permittivity and permeability dyadics of the medium are symmetric. • The formulation covers isotropic, biisotropic, and gyrotropic-like uniaxial mediums for which the Huygens principle is already available. • The formulation also covers new mediums like biaxial, chiro-omega, pseudo chiral, gyrotropic-like biaxial, and Lorentz reciprocal mediums.

  6. Carbon-hydrogen-related complexes in Si

    Science.gov (United States)

    Kolkovsky, Vl.; Stübner, R.; Gwozdz, K.; Weber, J.

    2018-04-01

    Several deep level transient spectroscopy (DLTS) peaks (E42, E65, E75, E90, E262, and H180) are observed in n- and p-type Czochralski-grown Si samples subjected to hydrogenation by a dc H plasma treatment. The concentration of the defects is found to be proportional to the carbon and hydrogen content in our samples. The analysis of the depth profiles performed in Si samples hydrogenated by wet chemically etching shows that all these defects contain a single H atom. E65 and E75 appear only in samples with a high oxygen content which shows that oxygen is a constituent of these defects. The analysis of the enhancement of the emission rate of the defects with electric field shows that E65, E75, E90, and E262 are single acceptors whereas E42 is a double acceptor. The presence of a barrier for hole capture (about 53 meV) can explain the absence of the enhancement of the emission rate of H180, which can be attributed to a single acceptor state. From a comparison with theory, we assign E90 to CH1BC, E42 (E262) to CH1AB, and H180 to CH1Td. The similarity of the electrical properties of E65 and E75 to those of E90 suggest that E65 and E75 may originate from the CH1BC defect with an oxygen atom in its nearest neighborhood. Our results on the CH-related complexes give a conclusive explanation of some previously reported controversial experimental data.

  7. Communication: Modeling electrolyte mixtures with concentration dependent dielectric permittivity

    Science.gov (United States)

    Chen, Hsieh; Panagiotopoulos, Athanassios Z.

    2018-01-01

    We report a new implicit-solvent simulation model for electrolyte mixtures based on the concept of concentration dependent dielectric permittivity. A combining rule is found to predict the dielectric permittivity of electrolyte mixtures based on the experimentally measured dielectric permittivity for pure electrolytes as well as the mole fractions of the electrolytes in mixtures. Using grand canonical Monte Carlo simulations, we demonstrate that this approach allows us to accurately reproduce the mean ionic activity coefficients of NaCl in NaCl-CaCl2 mixtures at ionic strengths up to I = 3M. These results are important for thermodynamic studies of geologically relevant brines and physiological fluids.

  8. Ring complexes and related rocks in Africa

    Science.gov (United States)

    Vail, J. R.

    Over 625 igneous complexes throughout Africa and Arabia have been selected and classified on the basis of petrographic association and chronology into six broad age groups forming 29 provinces. The groups range from Mid-Proterozoic to Tertiary and include gabbro, granite, syenite, foid syenite and carbonatite plutonic rocks, the majority in the form of ring-dykes, cone-sheets, plugs, circular intrusions, and their associated extrusive phases. Pan-African late or post-orogenic complexes (720-490 Ma) are common in the Arabian-Nubian and Tuareg shields of north Africa originating from subduction zone derived magmatism. Anorogenic complexes in Egypt, NE and central Sudan, Niger, Nigeria, Cameroon, Zaïre-Burundi, Malawi, Mozambique, Zimbabwe, Namibia and Angola span 550 to 50 Ma and are dominantly alkali granites and foid syenites. Many groups occur as en-echelon bands within linear arrays, and show migrating centres of intrusion in variable directions. In W. Africa there was a progressive shift of emplacement southwards during early Ordovician to Mid-Cretaceous times. Distribution patterns suggest thatdeep seated features, such as shear zones associated with lithospheric plate movements,controlled melting, and the resultant location of the complexes. Economic mineralization is not widespread in the rocks of the African ring complexes and is mainly restricted to small deposits of Sn, W, F, U and Nb.

  9. Internal homogenization: effective permittivity of a coated sphere.

    Science.gov (United States)

    Chettiar, Uday K; Engheta, Nader

    2012-10-08

    The concept of internal homogenization is introduced as a complementary approach to the conventional homogenization schemes, which could be termed as external homogenization. The theory for the internal homogenization of the permittivity of subwavelength coated spheres is presented. The effective permittivity derived from the internal homogenization of coreshells is discussed for plasmonic and dielectric constituent materials. The effective model provided by the homogenization is a useful design tool in constructing coated particles with desired resonant properties.

  10. Kubo formula for frequency dispersion of dielectric permittivity and static conductivity of the Coulomb system

    International Nuclear Information System (INIS)

    Bobrov, V.B.; Trigger, S.A.; Zagorodny, A.G.

    2010-01-01

    It is proved that the Kubo formula for the conductivity σ(ω) is valid at real frequencies ω. On this basis, an exact relation is derived for the static conductivity σ st of the Coulomb system. It is shown that the static conductivity is determined by the time correlation function in the limit t→∞. It is proved that the permittivity ε(ω) satisfies the Kramers-Kronig relations which take into account a singularity associated with static conductivity.

  11. Symmetry, Contingency, Complexity: Accommodating Uncertainty in Public Relations Theory.

    Science.gov (United States)

    Murphy, Priscilla

    2000-01-01

    Explores the potential of complexity theory as a unifying theory in public relations, where scholars have recently raised problems involving flux, uncertainty, adaptiveness, and loss of control. Describes specific complexity-based methodologies and their potential for public relations studies. Offers an account of complexity theory, its…

  12. Complex permittivity measurements of ferroelectric employing composite dielectric resonator technique

    Czech Academy of Sciences Publication Activity Database

    Krupka, J.; Zychowicz, T.; Bovtun, Viktor; Veljko, Sergiy

    2006-01-01

    Roč. 53, č. 10 (2006), s. 1883-1888 ISSN 0885-3010 R&D Projects: GA AV ČR(CZ) IAA1010213; GA ČR(CZ) GA202/04/0993; GA ČR(CZ) GA202/06/0403 Institutional research plan: CEZ:AV0Z10100520 Keywords : dielectric resonator * ferroelectrics * microwave measurements Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.729, year: 2006

  13. Fabrication of Composite Filaments with High Dielectric Permittivity for Fused Deposition 3D Printing.

    Science.gov (United States)

    Wu, Yingwei; Isakov, Dmitry; Grant, Patrick S

    2017-10-23

    Additive manufacturing of complex structures with spatially varying electromagnetic properties can enable new applications in high-technology sectors such as communications and sensors. This work presents the fabrication method as well as microstructural and dielectric characterization of bespoke composite filaments for fused deposition modeling (FDM) 3D printing of microwave devices with a high relative dielectric permittivity ϵ = 11 in the GHz frequency range. The filament is composed of 32 vol % of ferroelectric barium titanate (BaTiO 3 ) micro-particles in a polymeric acrylonitrile butadiene styrene (ABS) matrix. An ionic organic ester surfactant was added during formulation to enhance the compatibility between the polymer and the BaTiO 3 . To promote reproducible and robust printability of the fabricated filament, and to promote plasticity, dibutyl phthalate was additionally used. The combined effect of 1 wt % surfactant and 5 wt % plasticizer resulted in a uniform, many hundreds of meters, continuous filament of commercial quality capable of many hours of uninterrupted 3D printing. We demonstrate the feasibility of using the high dielectric constant filament for 3D printing through the fabrication of a range of optical devices. The approach herein may be used as a guide for the successful fabrication of many types of composite filament with varying functions for a broad range of applications.

  14. Fabrication of Composite Filaments with High Dielectric Permittivity for Fused Deposition 3D Printing

    Directory of Open Access Journals (Sweden)

    Yingwei Wu

    2017-10-01

    Full Text Available Additive manufacturing of complex structures with spatially varying electromagnetic properties can enable new applications in high-technology sectors such as communications and sensors. This work presents the fabrication method as well as microstructural and dielectric characterization of bespoke composite filaments for fused deposition modeling (FDM 3D printing of microwave devices with a high relative dielectric permittivity ϵ = 11 in the GHz frequency range. The filament is composed of 32 vol % of ferroelectric barium titanate (BaTiO 3 micro-particles in a polymeric acrylonitrile butadiene styrene (ABS matrix. An ionic organic ester surfactant was added during formulation to enhance the compatibility between the polymer and the BaTiO 3 . To promote reproducible and robust printability of the fabricated filament, and to promote plasticity, dibutyl phthalate was additionally used. The combined effect of 1 wt % surfactant and 5 wt % plasticizer resulted in a uniform, many hundreds of meters, continuous filament of commercial quality capable of many hours of uninterrupted 3D printing. We demonstrate the feasibility of using the high dielectric constant filament for 3D printing through the fabrication of a range of optical devices. The approach herein may be used as a guide for the successful fabrication of many types of composite filament with varying functions for a broad range of applications.

  15. Application of Jonscher model for the characterization of the dielectric permittivity of concrete

    International Nuclear Information System (INIS)

    Bourdi, Taoufik; Rhazi, Jamal Eddine; Ballivy, Gerard; Boone, Francois

    2008-01-01

    The study of electromagnetic waves propagating in concrete is a complex problem. Understanding the phenomenon of interaction between the wave and the matter is related to the knowledge of the variation process of concrete's electromagnetic properties in terms of its physical characteristics. In particular, dielectric permittivity of concrete is affected by moisture content and change in the frequency of the electromagnetic field applied. In this study, we apply the three-parameter Jonscher model (n, χ r , ε ∞ ) to show the dispersive aspect of the concrete. The validation of this model is carried out through tests on mortar and concrete at the laboratory, on the one hand, and by comparison of the results with data obtained previously by other researchers, on the other hand. The Jonscher model matches very well the experimental measurements of the concrete. At different moisture levels, heterogeneities and porosities, the results obtained are very good. This shows that this model is very effective and very suitable to represent the dielectric properties of concrete.

  16. Application of Jonscher model for the characterization of the dielectric permittivity of concrete

    Energy Technology Data Exchange (ETDEWEB)

    Bourdi, Taoufik; Rhazi, Jamal Eddine; Ballivy, Gerard [Groupe de recherche en auscultation et instrumentation, Department of Civil Engineering, University of Sherbrooke, Sherbrooke (QC), J1K2R1 (Canada); Boone, Francois [Laboratoire d' Electronique Micro-Ondes, Department of Electrical Engineering and Engineering computer, University of Sherbrooke, Sherbrooke (QC), J1K2R1 (Canada)], E-mail: Taoufik.Bourdi@Usherbrooke.ca

    2008-10-21

    The study of electromagnetic waves propagating in concrete is a complex problem. Understanding the phenomenon of interaction between the wave and the matter is related to the knowledge of the variation process of concrete's electromagnetic properties in terms of its physical characteristics. In particular, dielectric permittivity of concrete is affected by moisture content and change in the frequency of the electromagnetic field applied. In this study, we apply the three-parameter Jonscher model (n, {chi}{sub r}, {epsilon}{sub {infinity}}) to show the dispersive aspect of the concrete. The validation of this model is carried out through tests on mortar and concrete at the laboratory, on the one hand, and by comparison of the results with data obtained previously by other researchers, on the other hand. The Jonscher model matches very well the experimental measurements of the concrete. At different moisture levels, heterogeneities and porosities, the results obtained are very good. This shows that this model is very effective and very suitable to represent the dielectric properties of concrete.

  17. The precipitation in annealing and its effect on permittivity of Fe–Si–Al powders

    International Nuclear Information System (INIS)

    Li, Gang; Cui, Yin; Zhang, Nan; Wang, Xin; Xie, Jian Liang

    2016-01-01

    SEM images show that some precipitates distributed on the surface of as-annealed Fe–Si–Al powders. Subsequent experimental results indicate that both morphology and microstructure of as-annealed Fe–Si–Al powders change with increasing annealing temperature. Meanwhile, dielectric properties analysis suggesting that both real part ε′ and imaginary part ε″ of the Fe–Si–Al powders decrease significantly after annealed at 450 °C or higher temperature. We assume that it’s the precipitates with low electrical conductivity developed on the surface of powders that increase the surface resistivity of as-annealed powders and leading to a lower imagine part of permittivity. The drop of real part ε′ ascribed to the weakened interfacial polarization which resulted from the decrease of structural defects such as grain boundaries and interfaces during annealing process. - Highlights: • As-milled Fe–Si–Al powders were annealed at various temperature. • The change of morphology and microstructure of as-annealed Fe–Si–Al was examined. • Complex permittivity decrease significantly after annealed over 400 °C and permeability increase as annealing temperature rises. • The precipitation process in annealing and its effect on permittivity were analyzed.

  18. Electron irradiation induced reduction of the permittivity in chalcogenide glass (As2S3) thin film

    KAUST Repository

    San Roman Alerigi, Damian; Anjum, Dalaver H.; Zhang, Yaping; Yang, Xiaoming; Ben Slimane, Ahmed; Ng, Tien Khee; Hedhili, Mohamed N.; Alsunaidi, Mohammad; Ooi, Boon S.

    2013-01-01

    In this paper, we investigate the effect of electron beam irradiation on the dielectric properties of As 2 S 3 chalcogenide glass. By means of low-loss electron energy loss spectroscopy, we derive the permittivity function, its dispersive relation, and calculate the refractive index and absorption coefficients under the constant permeability approximation. The measured and calculated results show a heretofore unseen phenomenon: a reduction in the permittivity of ? 40 %. Consequently a reduction of the refractive index of 20%, hence, suggests a conspicuous change in the optical properties of the material under irradiation with a 300 keV electron beam. The plausible physical phenomena leading to these observations are discussed in terms of the homopolar and heteropolar bond dynamics under high energy absorption. The reported phenomena, exhibited by As 2 S 3-thin film, can be crucial for the development of photonics integrated circuits using electron beam irradiation method. © 2013 American Institute of Physics.

  19. Super soft silicone elastomers with high dielectric permittivity

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Hvilsted, Søren

    2015-01-01

    Dielectric elastomers (DEs) have many favourable properties. The obstacle of high driving voltages, however, limits the commercial viability of the technology at present. Driving voltage can be lowered by decreasing the Young’s modulus and increasing the dielectric permittivity of silicone...... elastomers. A decrease in Young’s modulus, however, is often accompanied by the loss of mechanical stability and thereby the lifetime of the DE. New soft elastomer matrices with high dielectric permittivity and low Young’s modulus, with no loss of mechanical stability, were prepared by two different...... approaches using chloropropyl-functional silicone polymers. The first approach was based on synthesised chloropropyl-functional copolymers that were cross-linkable and thereby formed the basis of new silicone networks with high dielectric permittivity (e.g. a 43% increase). These networks were soft without...

  20. An automated phase correction algorithm for retrieving permittivity and permeability of electromagnetic metamaterials

    Directory of Open Access Journals (Sweden)

    Z. X. Cao

    2014-06-01

    Full Text Available To retrieve complex-valued effective permittivity and permeability of electromagnetic metamaterials (EMMs based on resonant effect from scattering parameters using a complex logarithmic function is not inevitable. When complex values are expressed in terms of magnitude and phase, an infinite number of permissible phase angles is permissible due to the multi-valued property of complex logarithmic functions. Special attention needs to be paid to ensure continuity of the effective permittivity and permeability of lossy metamaterials as frequency sweeps. In this paper, an automated phase correction (APC algorithm is proposed to properly trace and compensate phase angles of the complex logarithmic function which may experience abrupt phase jumps near the resonant frequency region of the concerned EMMs, and hence the continuity of the effective optical properties of lossy metamaterials is ensured. The algorithm is then verified to extract effective optical properties from the simulated scattering parameters of the four different types of metamaterial media: a cut-wire cell array, a split ring resonator (SRR cell array, an electric-LC (E-LC resonator cell array, and a combined SRR and wire cell array respectively. The results demonstrate that the proposed algorithm is highly accurate and effective.

  1. Dielectric elastomer actuators using Slide-Ring Material® with increased permittivity

    International Nuclear Information System (INIS)

    Tsuchitani, Shigeki; Miki, Hirofumi; Sunahara, Tokiharu

    2015-01-01

    The inclusion of high permittivity nanoparticles in elastomeric materials for dielectric elastomer actuators (DEAs) is one promising method to achieve large strain at relatively low applied voltages. However, the addition of these nanoparticles tends to increase the stiffness of the elastomer and disturbs the actuation of the DEA. This is attributed to restriction of the chain motion in the elastomer by the nanoparticles. Slide-Ring Material ® (SRM) is a cross-linked polymeric material with freely movable cross-linking sites. The internal stresses in this structure are dramatically homogenized by the pulley effect; therefore, the restriction of chain motion due to the nanoparticles is expected to be significantly reduced. We have employed SRM as a host elastomer for a DEA with the addition of ferroelectric BaTiO 3 (BT) nanoparticles. The effects of BT addition on the permittivity, stiffness and viscosity of the SRM–BT nanocomposites, and the actuation strain of DEAs using SRM were evaluated. The permittivity of the nanocomposites increased linearly with the concentration of BT and reached 3.6 times that for pure SRM at 50 wt%. The elastic modulus and the viscosity remained almost constant up to 20 wt% and then decreased above this concentration. The actuation strain of a planar actuator using SRM and 50 wt% BT was four times larger than that of the DEA with pure SRM. (paper)

  2. The Effect of Variation in Permittivity of Different Tissues on Induced Electric Field in the Brain during Transcranial Magnetic Stimulation

    Science.gov (United States)

    Hadimani, Ravi; Porzig, Konstantin; Crowther, Lawrence; Brauer, Hartmut; Toepfer, Hannes; Jiles, David; Department of Electrical and Computer Engineering, Iowa State University Team; Department of Advanced Electromagnetics, Ilmenau University of Technology Team

    2013-03-01

    Estimation of electric field in the brain during Transcranial Magnetic Stimulation (TMS) requires knowledge of the electric property of brain tissue. Grey and white matters have unusually high relative permittivities of ~ 106 at low frequencies. However, relative permittivity of cerebrospinal fluid is ~ 102. With such a variation it is necessary to consider the effect of boundaries. A model consisting of 2 hemispheres was used in the model with the properties of one hemisphere kept constant at σ1 = 0.1Sm-1 and ɛr 1 = 10 while the properties of the second hemisphere were changed kept at σ2 = 0.1Sm-1 to 2Sm-1 and ɛr 2 = 102 to 105. A 70 mm diameter double coil was used as the source of the magnetic field. The amplitude of the current in the coil was 5488 A at a frequency of 2.9 kHz. The results show that the electric field, E induced during magnetic stimulation is independent of the relative permittivity, ɛr and varies with the conductivity. Thus the variation in E, calculated with homogeneous and heterogeneous head models was due to variation in conductivity of the tissues and not due to variation in permittivities.

  3. Permittivity disorder induced Anderson localization in magnetophotonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Abdi-Ghaleh, R., E-mail: r.abdi@bonabu.ac.ir [Department of Laser and Optical Engineering, University of Bonab, 5551761167 Bonab (Iran, Islamic Republic of); Namdar, A. [Faculty of Physics, University of Tabriz, 5166614766 Tabriz (Iran, Islamic Republic of)

    2016-11-15

    This theoretical study was carried out to investigate the permittivity disorder induced Anderson localization of light in one-dimensional magnetophotonic crystals. It was shown that the disorder create the resonant transmittance modes associated with enhanced Faraday rotations inside the photonic band gap. The average localization length of the right- and left-handed circular polarizations (RCP and LCP), the total transmittance together with the ensemble average of the RCP and LCP phases, and the Faraday rotation of the structure were also investigated. For this purpose, the off-diagonal elements of the permittivity tensor were varied for various wavelengths of incident light. The obtained results revealed the nonreciprocal property of circular eigen modes. This study can potentially open up a new aspect for utilizing the disorder magnetophotonic structures in nonreciprocal systems such as isolators and circulators. - Highlights: • We theoretically investigated the permittivity disorder induced Anderson localization of light in magnetophotonic crystals. • The disorder considered in the diagonal elements of the permittivity tensor of magneto-optical layers. • The disorder create the resonant transmittance modes associated with enhanced Faraday rotations in the photonic band gap. • The average localization length of the circular polarizations and the ensemble average of their phases were investigated. • The obtained results revealed the nonreciprocal property of circular eigen modes.

  4. Spinor formalism and complex-vector formalism of general relativity

    International Nuclear Information System (INIS)

    Han-ying, G.; Yong-shi, W.; Gendao, L.

    1974-01-01

    In this paper, using E. Cartan's exterior calculus, we give the spinor form of the structure equations, which leads naturally to the Newman--Penrose equations. Furthermore, starting from the spinor spaces and the el (2C) algebra, we construct the general complex-vector formalism of general relativity. We find that both the Cahen--Debever--Defrise complex-vector formalism and that of Brans are its special cases. Thus, the spinor formalism and the complex-vector formalism of general relativity are unified on the basis of the uni-modular group SL(2C) and its Lie algebra

  5. Spatial analogies pervade complex relational reasoning: Evidence from spontaneous gestures.

    Science.gov (United States)

    Cooperrider, Kensy; Gentner, Dedre; Goldin-Meadow, Susan

    2016-01-01

    How do people think about complex phenomena like the behavior of ecosystems? Here we hypothesize that people reason about such relational systems in part by creating spatial analogies, and we explore this possibility by examining spontaneous gestures. In two studies, participants read a written lesson describing positive and negative feedback systems and then explained the differences between them. Though the lesson was highly abstract and people were not instructed to gesture, people produced spatial gestures in abundance during their explanations. These gestures used space to represent simple abstract relations (e.g., increase ) and sometimes more complex relational structures (e.g., negative feedback ). Moreover, over the course of their explanations, participants' gestures often cohered into larger analogical models of relational structure. Importantly, the spatial ideas evident in the hands were largely unaccompanied by spatial words. Gesture thus suggests that spatial analogies are pervasive in complex relational reasoning, even when language does not.

  6. Improving dielectric permittivity by incorporating PDMS-PEG block copolymer into PDMS network

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Szabo, Peter; Skov, Anne Ladegaard

    introduces different properties in terms of contact angles, dielectric permittivity and rheological behaviour. All morphologies of PDMS-PEG block copolymer in this study exhibit high storage permittivity; at the same time the loss permittivity is even higher which implies that the synthesized PDMS-PEG block...

  7. Novel encapsulation technique for incorporation of high permittivity fillers into silicone elastomers

    DEFF Research Database (Denmark)

    Mazurek, Piotr Stanislaw; Hvilsted, Søren; Skov, Anne Ladegaard

    2014-01-01

    permittivity fillers, 2) Grafting of high permittivity molecules onto the polymer backbone in the elastomer, and 3) Encapsulation of high permittivity fillers. The approach investigated here is a new type of encapsulation which does not interfere with the mechanical properties to the same content...

  8. Imaging electrical conductivity, permeability, and/or permittivity contrasts using the Born Scattering Inversion (BSI)

    Science.gov (United States)

    Darrh, A.; Downs, C. M.; Poppeliers, C.

    2017-12-01

    Born Scattering Inversion (BSI) of electromagnetic (EM) data is a geophysical imaging methodology for mapping weak conductivity, permeability, and/or permittivity contrasts in the subsurface. The high computational cost of full waveform inversion is reduced by adopting the First Born Approximation for scattered EM fields. This linearizes the inverse problem in terms of Born scattering amplitudes for a set of effective EM body sources within a 3D imaging volume. Estimation of scatterer amplitudes is subsequently achieved by solving the normal equations. Our present BSI numerical experiments entail Fourier transforming real-valued synthetic EM data to the frequency-domain, and minimizing the L2 residual between complex-valued observed and predicted data. We are testing the ability of BSI to resolve simple scattering models. For our initial experiments, synthetic data are acquired by three-component (3C) electric field receivers distributed on a plane above a single point electric dipole within a homogeneous and isotropic wholespace. To suppress artifacts, candidate Born scatterer locations are confined to a volume beneath the receiver array. Also, we explore two different numerical linear algebra algorithms for solving the normal equations: Damped Least Squares (DLS), and Non-Negative Least Squares (NNLS). Results from NNLS accurately recover the source location only for a large dense 3C receiver array, but fail when the array is decimated, or is restricted to horizontal component data. Using all receiver stations and all components per station, NNLS results are relatively insensitive to a sub-sampled frequency spectrum, suggesting that coarse frequency-domain sampling may be adequate for good target resolution. Results from DLS are insensitive to diminishing array density, but contain spatially oscillatory structure. DLS-generated images are consistently centered at the known point source location, despite an abundance of surrounding structure.

  9. Quantum physics, relativity and complex spacetime towards a new synthesis

    CERN Document Server

    Kaiser, Gerald

    1990-01-01

    A new synthesis of the principles of quantum mechanics and Relativity is proposed in the context of complex differential geometry. The positivity of the energy implies that wave functions and fields can be extended to complex spacetime, and it is shown that this complexification has a solid physical interpretation as an extended phase space. The extended fields can be said to be realistic wavelet transforms of the original fields. A new, algebraic theory of wavelets is developed.

  10. Effective permittivity of random composite media: A comparative study

    International Nuclear Information System (INIS)

    Prasad, Ashutosh; Prasad, K.

    2007-01-01

    In the present study, experimental data for effective permittivity of amorphous, polycrystalline thick films, and ceramic form of samples, taken from the literature, have been chosen for their comparison with those yielded by different mixture equations. In order to test the acceptability of dielectric mixture equations for high volume fractions of the inclusion material in the mixture, eleven such equations have been chosen. It is found that equations given by Cuming, Maxwell-Wagner, Webmann, Skipetrov and modified Cule-Torquato show their coherence and minimal deviation from the experimental results of permittivity for all the chosen test materials almost over the entire measurement range of volume fractions. It is further found that Maxwell-Wagner, Webmann, and Skipetrov equations yielded equivalent results and consequently they have been combined together and reckoned as a single equation named MWWS. The study revealed that the Cuming equation had the highest degree of acceptability (errors <±1-5%) in all the cases

  11. Effective Permittivity for FDTD Calculation of Plasmonic Materials

    Directory of Open Access Journals (Sweden)

    James B. Cole

    2012-03-01

    Full Text Available We present a new effective permittivity (EP model to accurately calculate surface plasmons (SPs using the finite-difference time-domain (FDTD method. The computational representation of physical structures with curved interfaces causes inherent errors in FDTD calculations, especially when the numerical grid is coarse. Conventional EP models improve the errors, but they are not effective for SPs because the SP resonance condition determined by the original permittivity is changed by the interpolated EP values. We perform FDTD simulations using the proposed model for an infinitely-long silver cylinder and gold sphere, and the results are compared with Mie theory. Our model gives better accuracy than the conventional staircase and EP models for SPs.

  12. Negative permittivity chamber inside a stack of silver nanorings

    Science.gov (United States)

    Chen, Sheng Chung; Shiu Chau, Jr.

    2010-05-01

    The interactions of silver nanorings with polarized optical wave are numerically studied. If the resonant conditions are tuned, the polarization of incident field, inside the nanoring hole, will be reversed by the single silver nanoring due to the surface plasmon resonance, thus, the nanoring hole becomes a region of which permittivity is negative. Put two identical silver nanorings closely, there are two nodes happened between nanorings. It indicates that there is a very steep gradient of electric field and quasi-standing waves exist between nanorings. If many silver nanorings are lined up, the holes of the nanorings will form a negative permittivity chamber. The more close to the center of the chamber, the more ideal the polarization is reversed.

  13. Principal spectra describing magnetooptic permittivity tensor in cubic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Hamrlová, Jana [Nanotechnology Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); IT4Innovations Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Legut, Dominik [IT4Innovations Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Veis, Martin [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, Prague, 121 16 Czech Republic (Czech Republic); Pištora, Jaromír [Nanotechnology Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Hamrle, Jaroslav, E-mail: jaroslav.hamrle@vsb.cz [IT4Innovations Centre, VSB – Technical University of Ostrava, listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic); Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, Prague, 121 16 Czech Republic (Czech Republic); Department of Physics, VSB – Technical University of Ostrava, 17. listopadu 15, Ostrava, 708 33 Czech Republic (Czech Republic)

    2016-12-15

    We provide unified phenomenological description of magnetooptic effects being linear and quadratic in magnetization. The description is based on few principal spectra, describing elements of permittivity tensor up to the second order in magnetization. Each permittivity tensor element for any magnetization direction and any sample surface orientation is simply determined by weighted summation of the principal spectra, where weights are given by crystallographic and magnetization orientations. The number of principal spectra depends on the symmetry of the crystal. In cubic crystals owning point symmetry we need only four principal spectra. Here, the principal spectra are expressed by ab initio calculations for bcc Fe, fcc Co and fcc Ni in optical range as well as in hard and soft x-ray energy range, i.e. at the 2p- and 3p-edges. We also express principal spectra analytically using modified Kubo formula.

  14. Dipolar cross-linkers for PDMS networks with enhanced dielectric permittivity and low dielectric loss

    DEFF Research Database (Denmark)

    Bahrt, Frederikke; Daugaard, Anders Egede; Hvilsted, Søren

    2013-01-01

    -(4-((4-nitrophenyl)diazenyl)phenoxy)-prop-1-yn-1-ylium, with a synthesized silicone compatible azide-functional cross-linker by click chemistry. The thermal, mechanical and electromechanical properties were investigated for PDMS films with 0 to 3.6 wt% of dipole-cross-linker. The relative dielectric permittivity......Dipole grafted cross-linkers were utilized to prepare polydimethylsiloxane (PDMS) elastomers with various chain lengths and with various concentrations of functional cross-linker. The grafted cross-linkers were prepared by reaction of two alkyne-functional dipoles, 1-ethynyl-4-nitrobenzene and 3...

  15. Understanding dyadic promoter-stakeholder relations in complex projects

    Directory of Open Access Journals (Sweden)

    Janita Vos

    2016-01-01

    Full Text Available In this study, we propose a Bilateral Double Motive framework of stakeholder cooperation in complex projects. The framework analyses and explains dyadic promoter-stakeholder relationships at a micro level by acknowledging both transactional and relational motives. We demonstrate the framework’s usefulness by illustrating its explanatory power in two instances of cooperation and two of non-cooperation within two health information technology projects. The study contributes to project management theory through its combined focus on transactional and relational motives. Further, the study contributes to practice by providing a tool for planning and evaluating cooperation in health Information Technology projects and similar complex multi-stakeholder environments.

  16. Estimating porosity and solid dielectric permittivity in the Miami Limestone using high-frequency ground penetrating radar (GPR) measurements at the laboratory scale

    Science.gov (United States)

    Mount, Gregory J.; Comas, Xavier

    2014-10-01

    Subsurface water flow in South Florida is largely controlled by the heterogeneous nature of the karst limestone in the Biscayne aquifer and its upper formation, the Miami Limestone. These heterogeneities are amplified by dissolution structures that induce changes in the aquifer's material and physical properties (i.e., porosity and dielectric permittivity) and create preferential flow paths. Understanding such patterns are critical for the development of realistic groundwater flow models, particularly in the Everglades, where restoration of hydrological conditions is intended. In this work, we used noninvasive ground penetrating radar (GPR) to estimate the spatial variability in porosity and the dielectric permittivity of the solid phase of the limestone at centimeter-scale resolution to evaluate the potential for field-based GPR studies. A laboratory setup that included high-frequency GPR measurements under completely unsaturated and saturated conditions was used to estimate changes in electromagnetic wave velocity through Miami Limestone samples. The Complex Refractive Index Model was used to derive estimates of porosity and dielectric permittivity of the solid phase of the limestone. Porosity estimates of the samples ranged between 45.2 and 66.0% and showed good correspondence with estimates of porosity using analytical and digital image techniques. Solid dielectric permittivity values ranged between 7.0 and 13.0. This study shows the ability of GPR to image the spatial variability of porosity and dielectric permittivity in the Miami Limestone and shows potential for expanding these results to larger scales and other karst aquifers.

  17. Permittivity and modulus spectroscopic study of BaFe0.5Nb0.5O3 ceramics

    Directory of Open Access Journals (Sweden)

    Subrat K. Kar

    2013-12-01

    Full Text Available Ba(Fe0.5Nb0.5O3 (BFN powder was synthesized in single perovskite phase by conventional solid state reaction route and BFN ceramic was obtained by uniaxial pressing and sintering at 1350 °C. Complex immittance like: permittivity and modulus spectroscopic formalism were simultaneously used to explain dielectric behaviour of the ceramics. The activation energy calculated from dielectric relaxation below 100 °C was found to be ~0.19 eV. The activation energy obtained from modulus spectra above 100 °C was ~0.59 eV. The space charge polarization model was used to explain the origin of relaxation and “giant” permittivity of BFN ceramics near room temperature.

  18. Pedagogy of complex relationality exploring complexity theory, neuro-phenomenology, and attentiveness for education

    Science.gov (United States)

    Khattar, Randa

    What do the new sciences of complex relationality offer education? This work draws on complexity theory, neurological understandings of biology and phenomenology, and attentiveness to study what the new sciences might offer education and the possibilities of a pedagogical understanding of embodied knowing. Complexity theory provides understandings of local-global relationality, self-organization, far-from-equilibrium conditions, and emergent dynamics that are important for describing pedagogical relationality. In itself, however, complexity theory is lacking an attention to issues of embodiment that respond directly to an ethical understanding of relationality. Phenomenology provides important views on the human experience of perception, for example, Merleau-Ponty's, whose research opens up possibilities for embodiment and attentiveness. At the level of pedagogical practice, I will pose, following biologists Humberto Maturana and Francisco Varela's autopoietic self-making understanding of life, that attentiveness perspectives, which have been largely absent from western pedagogical theory and practice, are crucial to promoting embodied knowing for education. Maturana and Varela's autopoietic perspective offers an embodied understanding of living---and therefore education---which opens up necessary attentive spaces to listen to one another in non judgmental awareness in the present moment of experience. I offer insights into a relationally complex conception of education drawing on this biological and autopoietically-grounded framework. These insights are framed in the context of five clusters of relations: (1) emergence, far-from-equilibrium, and local-global relationality; (2) autopoietic autonomy, structural determination and sensory-motor coupling; (3) triggering perturbations, structural plasticity, and autopoietic organization; (4) knowing as adequate action, domains of interaction, and blind spots; and (5) attentiveness and responsive relationality. Four

  19. Development and characterization of ultrathin hafnium titanates as high permittivity gate insulators

    Science.gov (United States)

    Li, Min

    High permittivity or high-kappa materials are being developed for use as gate insulators for future ultrascaled metal oxide semiconductor field effect transistors (MOSFETs). Hafnium containing compounds are the leading candidates. Due to its moderate permittivity, however, it is difficult to achieve HfO2 gate structures with an EOT well below 1.0 nm. One approach to increase HfO2 permittivity is combining it with a very high-kappa material, such as TiO2. In this thesis, we systematically studied the electrical and physical characteristics of high-kappa hafnium titanates films as gate insulators. A series of HfxTi1-xO2 films with well-controlled composition were deposited using an MOCVD system. The physical properties of the films were analyzed using a variety of characterization techniques. X-ray micro diffraction indicates that the Ti-rich thin film is more immune to crystallization. TEM analysis showed that the thick stoichiometric HfTiO 4 film has an orthorhombic structure and large anisotropic grains. The C-V curves from the devices with the hafnium titanates films displayed relatively low hysteresis. In a certain composition range, the interfacial layer (IL) EOT and permittivity of HfxTi1-x O2 increases linearly with increasing Ti. The charge is negative for HfxTi1-xO2/IL and positive for Si/IL interface, and the magnitude increases as Hf increases. For ultra-thin films (less than 2 nm EOT), the leakage current increases with increasing HE Moreover, the Hf-rich sample has weaker temperature dependence of the current. In the MOSFET devices with the hafnium titanates films, normal transistor characteristics were observed, also electron mobility degradation. Next, we investigated the effects that different pre-deposition surface treatments, including HF dipping, NH3 surface nitridation, and HfO2 deposition, have on the electrical properties of hafnium titanates. Surface nitridation shows stronger effect than the thin HfO2 layer. The nitrided samples displayed a

  20. Complex Hollow Nanostructures: Synthesis and Energy-Related Applications.

    Science.gov (United States)

    Yu, Le; Hu, Han; Wu, Hao Bin; Lou, Xiong Wen David

    2017-04-01

    Hollow nanostructures offer promising potential for advanced energy storage and conversion applications. In the past decade, considerable research efforts have been devoted to the design and synthesis of hollow nanostructures with high complexity by manipulating their geometric morphology, chemical composition, and building block and interior architecture to boost their electrochemical performance, fulfilling the increasing global demand for renewable and sustainable energy sources. In this Review, we present a comprehensive overview of the synthesis and energy-related applications of complex hollow nanostructures. After a brief classification, the design and synthesis of complex hollow nanostructures are described in detail, which include hierarchical hollow spheres, hierarchical tubular structures, hollow polyhedra, and multi-shelled hollow structures, as well as their hybrids with nanocarbon materials. Thereafter, we discuss their niche applications as electrode materials for lithium-ion batteries and hybrid supercapacitors, sulfur hosts for lithium-sulfur batteries, and electrocatalysts for oxygen- and hydrogen-involving energy conversion reactions. The potential superiorities of complex hollow nanostructures for these applications are particularly highlighted. Finally, we conclude this Review with urgent challenges and further research directions of complex hollow nanostructures for energy-related applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. The semiotics of control and modeling relations in complex systems.

    Science.gov (United States)

    Joslyn, C

    2001-01-01

    We provide a conceptual analysis of ideas and principles from the systems theory discourse which underlie Pattee's semantic or semiotic closure, which is itself foundational for a school of theoretical biology derived from systems theory and cybernetics, and is now being related to biological semiotics and explicated in the relational biological school of Rashevsky and Rosen. Atomic control systems and models are described as the canonical forms of semiotic organization, sharing measurement relations, but differing topologically in that control systems are circularly and models linearly related to their environments. Computation in control systems is introduced, motivating hierarchical decomposition, hybrid modeling and control systems, and anticipatory or model-based control. The semiotic relations in complex control systems are described in terms of relational constraints, and rules and laws are distinguished as contingent and necessary functional entailments, respectively. Finally, selection as a meta-level of constraint is introduced as the necessary condition for semantic relations in control systems and models.

  2. Development of a new medium frequency EM device: Mapping soil water content variations using electrical conductivity and dielectric permittivity

    Science.gov (United States)

    Kessouri, P.; Buvat, S.; Tabbagh, A.

    2012-12-01

    Both electrical conductivity and dielectric permittivity of soil are influenced by its water content. Dielectric permittivity is usually measured in the high frequency range, using GPR or TDR, where the sensitivity to water content is high. However, its evaluation is limited by a low investigation depth, especially for clay rich soils. Electrical conductivity is closely related not only to soil water content, but also to clay content and soil structure. A simultaneous estimation of these electrical parameters can allow the mapping of soil water content variations for an investigation depth close to 1m. In order to estimate simultaneously both soil electrical conductivity and dielectric permittivity, an electromagnetic device working in the medium frequency range (between 100 kHz and 10 MHz) has been designed. We adopted Slingram geometry for the EM prototype: its PERP configuration (vertical transmission loop Tx and horizontal measuring loop Rx) was defined using 1D ground models. As the required investigation depth is around 1m, the coil spacing was fixed to 1.2m. This prototype works in a frequency range between 1 and 5 MHz. After calibration, we tested the response of prototype to objects with known properties. The first in situ measurements were led on experimental sites with different types of soils and different water content variations (artificially created or natural): sandy alluvium on a plot of INRA (French National Institute for Agricultural Research) in Orléans (Centre, France), a clay-loam soil on an experimental site in Estrée-Mons (Picardie, France) and fractured limestone at the vicinity of Grand (Vosges, France). In the case of the sandy alluvium, the values of dielectric permittivity measured are close to those of HF permittivity and allow the use of existing theoretical models to determine the soil water content. For soils containing higher amount of clay, the coupled information brought by the electrical conductivity and the dielectric

  3. Semiotic aspects of control and modeling relations in complex systems

    Energy Technology Data Exchange (ETDEWEB)

    Joslyn, C.

    1996-08-01

    A conceptual analysis of the semiotic nature of control is provided with the goal of elucidating its nature in complex systems. Control is identified as a canonical form of semiotic relation of a system to its environment. As a form of constraint between a system and its environment, its necessary and sufficient conditions are established, and the stabilities resulting from control are distinguished from other forms of stability. These result from the presence of semantic coding relations, and thus the class of control systems is hypothesized to be equivalent to that of semiotic systems. Control systems are contrasted with models, which, while they have the same measurement functions as control systems, do not necessarily require semantic relations because of the lack of the requirement of an interpreter. A hybrid construction of models in control systems is detailed. Towards the goal of considering the nature of control in complex systems, the possible relations among collections of control systems are considered. Powers arguments on conflict among control systems and the possible nature of control in social systems are reviewed, and reconsidered based on our observations about hierarchical control. Finally, we discuss the necessary semantic functions which must be present in complex systems for control in this sense to be present at all.

  4. Environmental influences on neural systems of relational complexity

    Directory of Open Access Journals (Sweden)

    Layne eKalbfleisch

    2013-09-01

    Full Text Available Constructivist learning theory contends that we construct knowledge by experience and that environmental context influences learning. To explore this principle, we examined the cognitive process relational complexity (RC, defined as the number of visual dimensions considered during problem solving on a matrix reasoning task and a well-documented measure of mature reasoning capacity. We sought to determine how the visual environment influences RC by examining the influence of color and visual contrast on RC in a neuroimaging task. To specify the contributions of sensory demand and relational integration to reasoning, our participants performed a non-verbal matrix task comprised of color, no-color line, or black-white visual contrast conditions parametrically varied by complexity (relations 0, 1, 2. The use of matrix reasoning is ecologically valid for its psychometric relevance and for its potential to link the processing of psychophysically specific visual properties with various levels of relational complexity during reasoning. The role of these elements is important because matrix tests assess intellectual aptitude based on these seemingly context-less exercises. This experiment is a first step toward examining the psychophysical underpinnings of performance on these types of problems. The importance of this is increased in light of recent evidence that intelligence can be linked to visual discrimination. We submit three main findings. First, color and black-white visual contrast add demand at a basic sensory level, but contributions from color and from black-white visual contrast are dissociable in cortex such that color engages a reasoning heuristic and black-white visual contrast engages a sensory heuristic. Second, color supports contextual sense-making by boosting salience resulting in faster problem solving. Lastly, when visual complexity reaches 2-relations, color and visual contrast relinquish salience to other dimensions of problem

  5. Relating Complexity and Error Rates of Ontology Concepts. More Complex NCIt Concepts Have More Errors.

    Science.gov (United States)

    Min, Hua; Zheng, Ling; Perl, Yehoshua; Halper, Michael; De Coronado, Sherri; Ochs, Christopher

    2017-05-18

    Ontologies are knowledge structures that lend support to many health-information systems. A study is carried out to assess the quality of ontological concepts based on a measure of their complexity. The results show a relation between complexity of concepts and error rates of concepts. A measure of lateral complexity defined as the number of exhibited role types is used to distinguish between more complex and simpler concepts. Using a framework called an area taxonomy, a kind of abstraction network that summarizes the structural organization of an ontology, concepts are divided into two groups along these lines. Various concepts from each group are then subjected to a two-phase QA analysis to uncover and verify errors and inconsistencies in their modeling. A hierarchy of the National Cancer Institute thesaurus (NCIt) is used as our test-bed. A hypothesis pertaining to the expected error rates of the complex and simple concepts is tested. Our study was done on the NCIt's Biological Process hierarchy. Various errors, including missing roles, incorrect role targets, and incorrectly assigned roles, were discovered and verified in the two phases of our QA analysis. The overall findings confirmed our hypothesis by showing a statistically significant difference between the amounts of errors exhibited by more laterally complex concepts vis-à-vis simpler concepts. QA is an essential part of any ontology's maintenance regimen. In this paper, we reported on the results of a QA study targeting two groups of ontology concepts distinguished by their level of complexity, defined in terms of the number of exhibited role types. The study was carried out on a major component of an important ontology, the NCIt. The findings suggest that more complex concepts tend to have a higher error rate than simpler concepts. These findings can be utilized to guide ongoing efforts in ontology QA.

  6. Simultaneous identification of electric permittivity and magnetic permeability

    International Nuclear Information System (INIS)

    Feng, Hui; Jiang, Daijun; Zou, Jun

    2010-01-01

    In this paper we investigate the simultaneous reconstruction of the electric permittivity and magnetic permeability. The two physical parameters are allowed to be highly discontinuous in the concerned physical domain. The ill-posed inverse problem is formulated into an output least-squares nonlinear minimization with BV-regularization. The regularizing effect and mathematical properties of the regularized system are justified and analysed. A fully discrete Nedelec's edge element method is applied to approximate the regularized nonlinear optimization system, and its convergence is demonstrated

  7. Self-Healing, High-Permittivity Silicone Dielectric Elastomer

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Skov, Anne Ladegaard

    2016-01-01

    possesses high dielectric permittivity and consists of an interpenetrating polymer network of silicone elastomer and ionic silicone species that are cross-linked through proton exchange between amines and acids. The ionically cross-linked silicone provides self-healing properties after electrical breakdown...... or cuts made directly to the material due to the reassembly of the ionic bonds that are broken during damage. The dielectric elastomers presented in this paper pave the way to increased lifetimes and the ability of dielectric elastomers to survive millions of cycles in high-voltage conditions....

  8. Measurement of mortar permittivity during setting using a coplanar waveguide

    International Nuclear Information System (INIS)

    Juan-García, P; Torrents, J M

    2010-01-01

    A sensor based on a coplanar waveguide structure was designed to perform non-destructive tests for material characterization in which the measurement can be done only on one side of the sample. The measurements were compared with the impedance of a capacitor filled with the same material. The permittivity and insertion loss of the sensor showed valuable information about the setting process of a mortar slab during the first 28 days of the hardening process, and a good correlation between both measurements was obtained, so the proposed setup can be useful for structural surveillance and moisture detection in civil structures

  9. Near surface bulk density estimates of NEAs from radar observations and permittivity measurements of powdered geologic material

    Science.gov (United States)

    Hickson, Dylan; Boivin, Alexandre; Daly, Michael G.; Ghent, Rebecca; Nolan, Michael C.; Tait, Kimberly; Cunje, Alister; Tsai, Chun An

    2018-05-01

    The variations in near-surface properties and regolith structure of asteroids are currently not well constrained by remote sensing techniques. Radar is a useful tool for such determinations of Near-Earth Asteroids (NEAs) as the power of the reflected signal from the surface is dependent on the bulk density, ρbd, and dielectric permittivity. In this study, high precision complex permittivity measurements of powdered aluminum oxide and dunite samples are used to characterize the change in the real part of the permittivity with the bulk density of the sample. In this work, we use silica aerogel for the first time to increase the void space in the samples (and decrease the bulk density) without significantly altering the electrical properties. We fit various mixing equations to the experimental results. The Looyenga-Landau-Lifshitz mixing formula has the best fit and the Lichtenecker mixing formula, which is typically used to approximate planetary regolith, does not model the results well. We find that the Looyenga-Landau-Lifshitz formula adequately matches Lunar regolith permittivity measurements, and we incorporate it into an existing model for obtaining asteroid regolith bulk density from radar returns which is then used to estimate the bulk density in the near surface of NEA's (101955) Bennu and (25143) Itokawa. Constraints on the material properties appropriate for either asteroid give average estimates of ρbd = 1.27 ± 0.33g/cm3 for Bennu and ρbd = 1.68 ± 0.53g/cm3 for Itokawa. We conclude that our data suggest that the Looyenga-Landau-Lifshitz mixing model, in tandem with an appropriate radar scattering model, is the best method for estimating bulk densities of regoliths from radar observations of airless bodies.

  10. Australian diagnosis related groups: Drivers of complexity adjustment.

    Science.gov (United States)

    Jackson, Terri; Dimitropoulos, Vera; Madden, Richard; Gillett, Steve

    2015-11-01

    In undertaking a major revision to the Australian Refined Diagnosis Related Group (ARDRG) classification, we set out to contrast Australia's approach to using data on additional (not principal) diagnoses with major international approaches in splitting base or Adjacent Diagnosis Related Groups (ADRGs). Comparative policy analysis/narrative review of peer-reviewed and grey literature on international approaches to use of additional (secondary) diagnoses in the development of Australian and international DRG systems. European and US approaches to characterise complexity of inpatient care are well-documented, providing useful points of comparison with Australia's. Australia, with good data sources, has continued to refine its national DRG classification using increasingly sophisticated approaches. Hospital funders in Australia and in other systems are often under pressure from provider groups to expand classifications to reflect clinical complexity. DRG development in most healthcare systems reviewed here reflects four critical factors: these socio-political factors, the quality and depth of the coded data available to characterise the mix of cases in a healthcare system, the size of the underlying population, and the intended scope and use of the classification. Australia's relatively small national population has constrained the size of its DRG classifications, and development has been concentrated on inpatient care in public hospitals. Development of casemix classifications in health care is driven by both technical and socio-political factors. Use of additional diagnoses to adjust for patient complexity and cost needs to respond to these in each casemix application. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. [Complex Trauma-related Disorders in Research and Practice].

    Science.gov (United States)

    Metzner, Franka; Pahlke, Stephanie; Diesing, Alice; Marin, Nina; Klasen, Fionna; Pawils, Silke; Schulte-Markwort, Michael; Richter-Appelt, Hertha

    2018-03-01

    Complex Trauma-related Disorders in Research and Practice Frequent traumata in childhood and adolescence are long-term or repeated interpersonal traumata caused by perpetrators in the close environment of the minors. For the description of the extensive symptoms after interpersonal Type II traumata, the complex trauma-related disorders Complex Posttraumatic Stress Disorder (CPTSD) or Disorder of Extreme Stress Not Otherwise Specified (DESNOS) and the Developmental Trauma Disorder (DTD) are being discussed for inclusion in the classification systems for mental disorders. Scientific knowledge and practical experiences regarding CPTSD, DESNOS and DTD in children and adolescents up to 18 years were examined by 1) a Systematic Review of 1,070 publications identified by database research and additional search strategies, and 2) a nationwide online survey of 374 psychotherapists and psychiatrists for children and adolescents in Germany. Of 13 included empirical studies (8 CPTSD or DESNOS, 5 DTD), 9 were conducted in the USA, 4 based on file coding and 3 on secondary data analysis and only 7 reported diagnosis rates (range: 0-78 %). Of the interviewed therapists, 100 % considered the CPTSD as being met with at least one patient with interpersonal traumata up to 18 years of age in 2014 and 99 % gave this estimate for the DTD. Two thirds of therapists rated the diagnostic option CPTSD and DTD as "very often" or "often" helpful for their therapeutic work with children and adolescents. While empirical data available is to be considered insufficient and characterized by methodological limitations, the relevance of complex trauma-related disorders is perceived as high by practitioners.

  12. Compact complex surfaces with geometric structures related to split quaternions

    International Nuclear Information System (INIS)

    Davidov, Johann; Grantcharov, Gueo; Mushkarov, Oleg; Yotov, Miroslav

    2012-01-01

    We study the problem of existence of geometric structures on compact complex surfaces that are related to split quaternions. These structures, called para-hypercomplex, para-hyperhermitian and para-hyperkähler, are analogs of the hypercomplex, hyperhermitian and hyperkähler structures in the definite case. We show that a compact 4-manifold carries a para-hyperkähler structure iff it has a metric of split signature together with two parallel, null, orthogonal, pointwise linearly independent vector fields. Every compact complex surface admitting a para-hyperhermitian structure has vanishing first Chern class and we show that, unlike the definite case, many of these surfaces carry infinite-dimensional families of such structures. We provide also compact examples of complex surfaces with para-hyperhermitian structures which are not locally conformally para-hyperkähler. Finally, we discuss the problem of non-existence of para-hyperhermitian structures on Inoue surfaces of type S 0 and provide a list of compact complex surfaces which could carry para-hypercomplex structures.

  13. Investigation of embedded perovskite nanoparticles for enhanced capacitor permittivities.

    Science.gov (United States)

    Krause, Andreas; Weber, Walter M; Pohl, Darius; Rellinghaus, Bernd; Verheijen, Marcel; Mikolajick, Thomas

    2014-11-26

    Growth experiments show significant differences in the crystallization of ultrathin CaTiO3 layers on polycrystalline Pt surfaces. While the deposition of ultrathin layers below crystallization temperature inhibits the full layer crystallization, local epitaxial growth of CaTiO3 crystals on top of specific oriented Pt crystals occurs. The result is a formation of crystals embedded in an amorphous matrix. An epitaxial alignment of the cubic CaTiO3 ⟨111⟩ direction on top of the underlying Pt {111} surface has been observed. A reduced forming energy is attributed to an interplay of surface energies at the {111} interface of both materials and CaTiO3 nanocrystallites facets. The preferential texturing of CaTiO3 layers on top of Pt has been used in the preparation of ultrathin metal-insulator-metal capacitors with 5-30 nm oxide thickness. The effective CaTiO3 permittivity in the capacitor stack increases to 55 compared to capacitors with amorphous layers and a permittivity of 28. The isolated CaTiO3 crystals exhibit a passivation of the CaTiO3 grain surfaces by the surrounding amorphous matrix, which keeps the capacitor leakage current at ideally low values comparable for those of amorphous thin film capacitors.

  14. An Ontology for Modeling Complex Inter-relational Organizations

    Science.gov (United States)

    Wautelet, Yves; Neysen, Nicolas; Kolp, Manuel

    This paper presents an ontology for organizational modeling through multiple complementary aspects. The primary goal of the ontology is to dispose of an adequate set of related concepts for studying complex organizations involved in a lot of relationships at the same time. In this paper, we define complex organizations as networked organizations involved in a market eco-system that are playing several roles simultaneously. In such a context, traditional approaches focus on the macro analytic level of transactions; this is supplemented here with a micro analytic study of the actors' rationale. At first, the paper overviews enterprise ontologies literature to position our proposal and exposes its contributions and limitations. The ontology is then brought to an advanced level of formalization: a meta-model in the form of a UML class diagram allows to overview the ontology concepts and their relationships which are formally defined. Finally, the paper presents the case study on which the ontology has been validated.

  15. Infinite Multiple Membership Relational Modeling for Complex Networks

    DEFF Research Database (Denmark)

    Mørup, Morten; Schmidt, Mikkel Nørgaard; Hansen, Lars Kai

    Learning latent structure in complex networks has become an important problem fueled by many types of networked data originating from practically all fields of science. In this paper, we propose a new non-parametric Bayesian multiplemembership latent feature model for networks. Contrary to existing...... multiplemembership models that scale quadratically in the number of vertices the proposedmodel scales linearly in the number of links admittingmultiple-membership analysis in large scale networks. We demonstrate a connection between the single membership relational model and multiple membership models and show...

  16. Nano-laminate vs. direct deposition of high permittivity gadolinium scandate on silicon by high pressure sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Feijoo, P.C., E-mail: pedronska@fis.ucm.es [Dpto. Física Aplicada III (Electricidad y Electrónica), Universidad Complutense de Madrid, Fac. de CC. Físicas. Av/Complutense S/N, E-28040 Madrid (Spain); Pampillón, M.A.; San Andrés, E. [Dpto. Física Aplicada III (Electricidad y Electrónica), Universidad Complutense de Madrid, Fac. de CC. Físicas. Av/Complutense S/N, E-28040 Madrid (Spain); Fierro, J.L.G. [Instituto de Catálisis y Petroleoquímica, Consejo Superior de Investigaciones Científicas, C/Marie Curie 2, E-28049 Cantoblanco (Spain)

    2015-10-30

    In this work we use the high pressure sputtering technique to deposit the high permittivity dielectric gadolinium scandate on silicon substrates. This nonconventional deposition technique prevents substrate damage and allows for growth of ternary compounds with controlled composition. Two different approaches were assessed: the first one consists of depositing the material directly from a stoichiometric GdScO{sub 3} target; in the second one, we anneal a nano-laminate of < 0.5 nm thick Gd{sub 2}O{sub 3} and Sc{sub 2}O{sub 3} films in order to control the composition of the scandate. Metal–insulator–semiconductor capacitors were fabricated with platinum gates for electrical characterization. Accordingly, we grew a Gd-rich Gd{sub 2−x}Sc{sub x}O{sub 3} film that, in spite of higher leakage currents, presents a better effective relative permittivity of 21 and lower density of defects. - Highlights: • GdScO is deposited on Si as a high permittivity dielectric by two procedures. • Films sputtered from GdScO{sub 3} target are Sc-rich and present thick interface SiO{sub x}. • Gd-rich GdScO is obtained from a nano-laminate sputtered from Sc{sub 2}O{sub 3} and Gd{sub 2}O{sub 3}. • Gd{sub 1.8}Sc{sub 0.2}O{sub 3} shows good effective permittivity and electrical properties.

  17. The permittivity of a plasma at cyclotron resonance in large amplitude e.m. fields

    NARCIS (Netherlands)

    Schram, D.C.

    1970-01-01

    The permittivity of a collisionless plasma as a function of field parameters is measured in standing and in travelling waves. In both experiments the permittivity remains finite at cyclotron resonance; the resonance is broadened and shifted towards higher values of the magnetic field strength. The

  18. Soil permittivity response to bulk electrical conductivity for selected soil water sensors

    Science.gov (United States)

    Bulk electrical conductivity can dominate the low frequency dielectric loss spectrum in soils, masking changes in the real permittivity and causing errors in estimated water content. We examined the dependence of measured apparent permittivity (Ka) on bulk electrical conductivity in contrasting soil...

  19. Making mobility-related disability better: a complex response to a complex problem

    Directory of Open Access Journals (Sweden)

    Rockwood Kenneth

    2012-10-01

    Full Text Available Abstract Mobility disability in older adults can arise from single system problems, such as discrete musculoskeletal injury. In frail older adults, however, mobility disability is part of a complex web of problems. The approach to their rehabilitation must take that complexity into account, as is reported by Fairhall et al. First, their overall health state must be assessed, which is achieved by a comprehensive geriatric assessment. The assessment can show how a particular patient came to be disabled, so that an individualized care plan can be worked out. Whether this approach works in general can be evaluated by looking at group differences in mean mobility test scores. Knowing whether it has worked in the individual patient requires an individualized measure. This is because not every patient starts from the same point, and not every patient achieves success by aiming for the same goal. For one patient, walking unassisted for three metres would be a triumph; for another it would be a tragedy. Unless we understand the complexity of the needs of frail older adults, we will neither be able to treat them effectively nor evaluate our efforts sensibly. Please see related article http://www.biomedcentral.com/1741-7015/10/120

  20. Making mobility-related disability better: a complex response to a complex problem.

    Science.gov (United States)

    Rockwood, Kenneth

    2012-10-15

    Mobility disability in older adults can arise from single system problems, such as discrete musculoskeletal injury. In frail older adults, however, mobility disability is part of a complex web of problems. The approach to their rehabilitation must take that complexity into account, as is reported by Fairhall et al. First, their overall health state must be assessed, which is achieved by a comprehensive geriatric assessment. The assessment can show how a particular patient came to be disabled, so that an individualized care plan can be worked out. Whether this approach works in general can be evaluated by looking at group differences in mean mobility test scores. Knowing whether it has worked in the individual patient requires an individualized measure. This is because not every patient starts from the same point, and not every patient achieves success by aiming for the same goal. For one patient, walking unassisted for three metres would be a triumph; for another it would be a tragedy. Unless we understand the complexity of the needs of frail older adults, we will neither be able to treat them effectively nor evaluate our efforts sensibly.Please see related article http://www.biomedcentral.com/1741-7015/10/120.

  1. The equivalent electrical permittivity of gas-solid mixtures at intermediate solid volume fractions.

    Energy Technology Data Exchange (ETDEWEB)

    Torczynski, John Robert; Ceccio, Steven Louis; Tortora, Paul Richard

    2005-07-01

    Several mixture models are evaluated for their suitability in predicting the equivalent permittivity of dielectric particles in a dielectric medium for intermediate solid volume fractions (0.4 to 0.6). Predictions of the Maxwell, Rayleigh, Bottcher and Bruggeman models are compared to computational simulations of several arrangements of solid particles in a gas and to the experimentally determined permittivity of a static particle bed. The experiment uses spherical glass beads in air, so air and glass permittivity values (1 and 7, respectively) are used with all of the models and simulations. The experimental system used to measure the permittivity of the static particle bed and its calibration are described. The Rayleigh model is found to be suitable for predicting permittivity over the entire range of solid volume fractions (0-0.6).

  2. Age-Related Changes in Electroencephalographic Signal Complexity

    Science.gov (United States)

    Zappasodi, Filippo; Marzetti, Laura; Olejarczyk, Elzbieta; Tecchio, Franca; Pizzella, Vittorio

    2015-01-01

    The study of active and healthy aging is a primary focus for social and neuroscientific communities. Here, we move a step forward in assessing electrophysiological neuronal activity changes in the brain with healthy aging. To this end, electroencephalographic (EEG) resting state activity was acquired in 40 healthy subjects (age 16–85). We evaluated Fractal Dimension (FD) according to the Higuchi algorithm, a measure which quantifies the presence of statistical similarity at different scales in temporal fluctuations of EEG signals. Our results showed that FD increases from age twenty to age fifty and then decreases. The curve that best fits the changes in FD values across age over the whole sample is a parabola, with the vertex located around age fifty. Moreover, FD changes are site specific, with interhemispheric FD asymmetry being pronounced in elderly individuals in the frontal and central regions. The present results indicate that fractal dimension well describes the modulations of brain activity with age. Since fractal dimension has been proposed to be related to the complexity of the signal dynamics, our data demonstrate that the complexity of neuronal electric activity changes across the life span of an individual, with a steady increase during young adulthood and a decrease in the elderly population. PMID:26536036

  3. Complex and real Hermite polynomials and related quantizations

    International Nuclear Information System (INIS)

    Cotfas, Nicolae; Gazeau, Jean Pierre; Gorska, Katarzyna

    2010-01-01

    It is known that the anti-Wick (or standard coherent state) quantization of the complex plane produces both canonical commutation rule and quantum spectrum of the harmonic oscillator (up to the addition of a constant). In this work, we show that these two issues are not necessarily coupled: there exists a family of separable Hilbert spaces, including the usual Fock-Bargmann space, and in each element in this family there exists an overcomplete set of unit-norm states resolving the unity. With the exception of the Fock-Bargmann case, they all produce non-canonical commutation relation whereas the quantum spectrum of the harmonic oscillator remains the same up to the addition of a constant. The statistical aspects of these non-equivalent coherent state quantizations are investigated. We also explore the localization aspects in the real line yielded by similar quantizations based on real Hermite polynomials.

  4. Changes in permittivity and density of molecular liquids under high pressure.

    Science.gov (United States)

    Kiselev, Vladimir D; Kornilov, Dmitry A; Konovalov, Alexander I

    2014-04-03

    We collected and analyzed the density and permittivity of 57 nonpolar and dipolar molecular liquids at different temperatures (143 sets) and pressures (555 sets). No equation was found that could accurately predict the change to polar liquid permittivity by the change of its density in the range of the pressures and temperatures tested. Consequently, the influence of high hydrostatic pressure and temperature on liquid permittivity may be a more complicated process compared to density changes. The pressure and temperature coefficients of permittivity can be drastically larger than the pressure and temperature coefficients of density, indicating that pressure and particularly temperature significantly affect the structure of molecular liquids. These changes have less influence on the density change but can strongly affect the permittivity change. The clear relationship between the tangent and secant moduli of the permittivity curvatures under pressure for various molecular liquids at different temperatures was obtained, from which one can calculate the Tait equation coefficients from the experimental values of the pressure influence on the permittivity at ambient pressure.

  5. Polymorphous GdScO3 as high permittivity dielectric

    International Nuclear Information System (INIS)

    Schäfer, A.; Rahmanizadeh, K.; Bihlmayer, G.; Luysberg, M.; Wendt, F.; Besmehn, A.; Fox, A.

    2015-01-01

    Four different polymorphs of GdScO 3 are assessed theoretically and experimentally with respect to their suitability as a dielectric. The calculations carried out by density functional theory reveal lattice constants, band gaps and the energies of formation of three crystal phases. Experimentally all three crystal phases and the amorphous phase can be realized as thin films by pulsed laser deposition using various growth templates. Their respective crystal structures are confirmed by X-ray diffraction and transmission electron microscopy reflecting the calculated lattice constants. X-ray photoelectron spectroscopy unveils the band gaps of the different polymorphs of GdScO 3 which are above 5 eV for all films demonstrating good insulating properties. From capacitance voltage measurements, high permittivities of up to 27 for hexagonal GdScO 3 are deduced. - Highlights: • Different epitaxial polymorph phases of GdScO 3 were grown by pulsed laser deposition. • The cubic phase of GdScO 3 is reported for the first time. • All phases are proven to be useful for the use in silicon based and III–V based microelectronic devices.

  6. PERMITTIVITY RESEARCH OF BIOLOGICAL SOLUTIONS IN GIGAHERTZ FREQUENCY RANGE

    Directory of Open Access Journals (Sweden)

    Anton S. Demin

    2017-07-01

    Full Text Available Subject of Research. We present results of permittivity research in gigahertz frequency range for saline and glucose solutions used in medical practice. Experiment results are substantiated theoretically on the basis of Debye-Cole model. Method. Researches have been carried out on blood plasma of healthy donor, water, normal saline and glucose solutions with different concentration from 3 to 12 mmol/l. Experiments have been performed by an active nearfield method based on measuring the impedance of a plane air-liquid boundary with open end of coaxial waveguide in the frequency range from 1 to 12 GHz. Measurement results have been processed with the use of vector analyzer computer system from Rohde & Schwarz. Transmittance spectra have been determined by means of IR-spectrometer from TENZOR-Bruker. Main Results. Simulation results have shown good agreement between the experimental results and the model, as well as the choice of the main parameters of the Debye-Cole model in the studied frequency range for all media. It has been shown that the range of 3-6 GHz can be considered as the main one in the development of diagnostic sensors for the non-invasive analysis of the glucose concentration in the human blood. Practical Relevance. Electrodynamic models of test fluid replacing human blood give the possibility to simulate the sensor basic characteristics for qualitative and quantitative estimation of glucose concentration in human blood and can be used to create an experimental sample of a non- invasive glucometer.

  7. Explicitly solvable complex Chebyshev approximation problems related to sine polynomials

    Science.gov (United States)

    Freund, Roland

    1989-01-01

    Explicitly solvable real Chebyshev approximation problems on the unit interval are typically characterized by simple error curves. A similar principle is presented for complex approximation problems with error curves induced by sine polynomials. As an application, some new explicit formulae for complex best approximations are derived.

  8. Relationship between tolerance factor and temperature coefficient of permittivity of temperature-stable high permittivity BaTiO3–Bi(MeO3 compounds

    Directory of Open Access Journals (Sweden)

    Natthaphon Raengthon

    2016-03-01

    Full Text Available The temperature coefficient of permittivity (TCε of BaTiO3–Bi(MeO3 solid solutions were investigated. It was determined that as the tolerance factor was decreased with the addition of Bi(MeO3, the TCε shifted from large negative values to TCε values approaching zero. It is proposed that the different bonding nature of the dopant cation affects the magnitude and temperature stability of the permittivity. This study suggests that the relationship between tolerance factor and TCε can be used as a guide to design new dielectric compounds exhibiting temperature-stable high permittivity characteristics, which is similar to past research on perovskite and pyrochlore-based microwave dielectrics.

  9. Ultra-high polarity ceramics induced extrinsic high permittivity of polymers contributing to high permittivity of 2-2 series composites

    Science.gov (United States)

    Feng, Yefeng; Zhang, Jianxiong; Hu, Jianbing; Peng, Cheng; He, Renqi

    2018-01-01

    Induced polarization at interface has been confirmed to have significant impact on the dielectric properties of 2-2 series composites bearing Si-based semi-conductor sheet and polymer layer. By compositing, the significantly elevated high permittivity in Si-based semi-conductor sheet should be responsible for the obtained high permittivity in composites. In that case, interface interaction could include two aspects namely a strong electrostatic force from high polarity polymeric layer and a newborn high polarity induced in Si-based ceramic sheet. In this work, this class of interface induced polarization was successfully extended into another 2-2 series composite system made up of ultra-high polarity ceramic sheet and high polarity polymer layer. By compositing, the greatly improved high permittivity in high polarity polymer layer was confirmed to strongly contribute to the high permittivity achieved in composites. In this case, interface interaction should consist of a rather large electrostatic force from ultra-high polarity ceramic sheet with ionic crystal structure and an enhanced high polarity induced in polymer layer based on a large polarizability of high polarity covalent dipoles in polymer. The dielectric and conductive properties of four designed 2-2 series composites and their components have been detailedly investigated. Increasing of polymer inborn polarity would lead to a significant elevating of polymer overall polarity in composite. Decline of inherent polarities in two components would result in a mild improving of polymer total polarity in composite. Introducing of non-polarity polymeric layer would give rise to a hardly unaltered polymer overall polarity in composite. The best 2-2 composite could possess a permittivity of ˜463 at 100 Hz 25.7 times of the original permittivity of polymer in it. This work might offer a facile route for achieving the promising composite dielectrics by constructing the 2-2 series samples from two high polarity

  10. Wireless network of stand-alone end effect probes for soil in situ permittivity measurements over the 100MHZ-6GHz frequency range

    Science.gov (United States)

    Demontoux, François; Bircher, Simone; Ruffié, Gilles; Bonnaudiin, Fabrice; Wigneron, Jean-Pierre; Kerr, Yann

    2017-04-01

    Microwave remote sensing and non-destructive analysis are a powerful way to provide properties estimation of materials. Numerous applications using microwave frequency behavior of materials (remote sensing above land surfaces, non-destructive analysis…) are strongly dependent on the material's permittivity (i.e. dielectric properties). This permittivity depends on numerous parameters such as moisture, texture, temperature, frequency or bulk density. Permittivity measurements are generally carried out in the laboratory. Additionally, dielectric mixing models allow, over a restricted range of conditions, the assessment of a material's permittivity. in-situ measurements are more difficult to obtain. Some in situ measurement probes based on permittivity properties of soil exist (e.g. Time Domain Reflectometers and Transmissometers, capacitance and impedance sensors). They are dedicated to the acquisition of soil moisture data based on permittivity (mainly the real part) estimations over a range of frequencies from around 50 MHz to 1 or 2 GHz. Other Dielectric Assessment Kits exist but they are expensive and they are rather dedicated to laboratory measurements. Furthermore, the user can't address specific issues related to particular materials (e.g. organic soils) or specific measurement conditions (in situ long time records). At the IMS Laboratory we develop probes for in situ soil permittivity measurements (real and imaginary parts) in the 0.5 - 6 GHz frequency range. They are based on the end effect phenomenon of a coaxial waveguide and so are called end effect probes in this paper. The probes can be connected to a portable Vector Network Analyzer (VNA, ANRITSU MS2026A) for the S11 coefficient measurements needed to compute permittivity. It is connected to a PC to record data using an USB connection. This measurement set-up is already used for in situ measurement of soil properties in the framework of the European Space Agency's (ESA) SMOS space mission. However

  11. Electromechanical stability of electro-active silicone filled with high permittivity particles undergoing large deformation

    International Nuclear Information System (INIS)

    Liu, Liwu; Liu, Yanju; Zhang, Zhen; Leng, Jinsong; Li, Bo

    2010-01-01

    In this paper, an expression for the permittivity of electro-active silicone undergoing large deformation with high permittivity particles filled uniformly has been proposed. Two expressions are proposed for the permittivity, one based on experimental tests and the other based on the theory of composite material. By applying the thermodynamic model incorporating linear dielectric permittivity and nonlinear hyperelastic performance, the mechanical performance and electromechanical stability of the coupling system constituted by silicone filled with PMN–PT have been studied. The results show that the critical electric field decreases, namely the stability performance of the system declines when the content of PMN–PT c(v) increases and the electrostrictive coefficients increase. The results are beneficial for us to understand deeply the influence of the filled particle on the stability performance of silicone and to guide the design and manufacture of actuators and sensors based on dielectric elastomers

  12. Light cones in relativity: Real, complex, and virtual, with applications

    International Nuclear Information System (INIS)

    Adamo, T. M.; Newman, E. T.

    2011-01-01

    We study geometric structures associated with shear-free null geodesic congruences in Minkowski space-time and asymptotically shear-free null geodesic congruences in asymptotically flat space-times. We show how in both the flat and asymptotically flat settings, complexified future null infinity I C + acts as a ''holographic screen,'' interpolating between two dual descriptions of the null geodesic congruence. One description constructs a complex null geodesic congruence in a complex space-time whose source is a complex worldline, a virtual source as viewed from the holographic screen. This complex null geodesic congruence intersects the real asymptotic boundary when its source lies on a particular open-string type structure in the complex space-time. The other description constructs a real, twisting, shear-free or asymptotically shear-free null geodesic congruence in the real space-time, whose source (at least in Minkowski space) is in general a closed-string structure: the caustic set of the congruence. Finally we show that virtually all of the interior space-time physical quantities that are identified at null infinity I + (center of mass, spin, angular momentum, linear momentum, and force) are given kinematic meaning and dynamical descriptions in terms of the complex worldline.

  13. Combustion-related studies using weakly-bonded complexes

    Energy Technology Data Exchange (ETDEWEB)

    Beaudet, R.A. [Univ. of Southern California, Los Angeles (United States)

    1993-12-01

    Binary van der Waals complexes involving species of interest to combustion research are prepared in supersonic free-jet expansions, and their photochemical and photophysical properties are probed by using IR tunable diode laser (TDL) spectroscopy. In the first phase, geometries and other molecular properties are being determined from vibration-rotational spectra. In the second phase, these complexes will be used as precursors to study photoinitiated reactions in precursor geometry limited environments. Two complementary classes of binary complexes are being investigated. The first involves molecular oxygen and hydrogen containing constituents (e.g. O{sub 2}-HCN, O{sub 2}-HF, O{sub 2}-HCl, O{sub 2}-HBr, O{sub 2}-HI and O{sub 2}-hydrocarbons). These species are interesting candidates for study since upon photodissociating the hydride portion, the reaction H and O{sub 2} via the vibrationally excited HO{sub 2} intermediate can conceivably be studied, (e.g. BrH-O{sub 2} + hv(193 nm) {yields} Br-H-O{sub 2} {yields} Br + HO{sub 2} {yields} Br + OH + O). High resolution IR spectroscopy of such complexes have not been obtained previously and the structural information deriving from IR spectra is certainly very useful for better designing and understanding photoinitiated reactions that occur in these complexes.

  14. On conductivity, permittivity, apparent diffusion coefficient, and their usefulness as cancer markers at MRI frequencies.

    Science.gov (United States)

    Hancu, Ileana; Roberts, Jeannette Christine; Bulumulla, Selaka; Lee, Seung-Kyun

    2015-05-01

    To investigate the permittivity and conductivity of cancerous and normal tissues, their correlation to the apparent diffusion coefficient (ADC), and the specificity that they could add to cancer detection. Breast and prostate carcinomas were induced in rats. Conductivity and permittivity measurements were performed in the anesthetized animals using a dielectric probe and an impedance analyzer between 50 and 270 MHz. The correlations between ADCs (measured at 128 MHz) and conductivity values were investigated. Frequency-dependent discriminant functions were computed to assess the value that each parameter adds to cancer detection. Tumors exhibited higher permittivity than muscle tissue by 27%/12%/5% at 64/128/270MHz. Frequency independent, 15-20% higher conductivity was also noted in tumors compared to muscle tissue over the same frequency range. Strong negative correlation was observed between tissue conductivity and ADC. Whereas permittivity had the strongest discriminatory power at 64 MHz, it became comparable to ADC at 128 MHz and less important than ADC at 270 MHz. Conductivity measurements offered limited advantages in separating cancer from normal tissue beyond what ADC already provided; conversely, permittivity added separation power when added to the discriminant function. The moderately high cancerous tissue permittivity and conductivity impose strong constraints on the capability of MRI-based tissue electrical property measurements. © 2014 Wiley Periodicals, Inc.

  15. Ionic conductivity and dielectric permittivity of PEO-LiClO4 solid polymer electrolyte plasticized with propylene carbonate

    Directory of Open Access Journals (Sweden)

    S. Das

    2015-02-01

    Full Text Available We have studied ionic conductivity and dielectric permittivity of PEO-LiClO4 solid polymer electrolyte plasticized with propylene carbonate. Differential scanning calorimetry and X-ray diffraction studies confirm minimum volume fraction of crystalline phase for the polymer electrolyte with 40 wt. % propylene carbonate. The ionic conductivity exhibits a maximum for the same composition. The temperature dependence of the ionic conductivity has been well interpreted using Vogel-Tamman-Fulcher equation. Ion-ion interactions in the polymer electrolytes have been studied using Raman spectra and the concentrations of free ions, ion-pairs and ion-aggregates have been determined. The ionic conductivity increases due to the increase of free ions with the increase of propylene carbonate content. But for higher content of propylene carbonate, the ionic conductivity decreases due to the increase of concentrations of ion-pairs and ion-aggregates. To get further insights into the ion dynamics, the experimental data for the complex dielectric permittivity have been studied using Havriliak–Negami function. The variation of relaxation time with temperature obtained from this formalism follows Vogel-Tamman-Fulcher equation similar to the ionic conductivity.

  16. Ionic conductivity and dielectric permittivity of PEO-LiClO{sub 4} solid polymer electrolyte plasticized with propylene carbonate

    Energy Technology Data Exchange (ETDEWEB)

    Das, S.; Ghosh, A., E-mail: sspag@iacs.res.in [Department of Solid State Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India)

    2015-02-15

    We have studied ionic conductivity and dielectric permittivity of PEO-LiClO{sub 4} solid polymer electrolyte plasticized with propylene carbonate. Differential scanning calorimetry and X-ray diffraction studies confirm minimum volume fraction of crystalline phase for the polymer electrolyte with 40 wt. % propylene carbonate. The ionic conductivity exhibits a maximum for the same composition. The temperature dependence of the ionic conductivity has been well interpreted using Vogel-Tamman-Fulcher equation. Ion-ion interactions in the polymer electrolytes have been studied using Raman spectra and the concentrations of free ions, ion-pairs and ion-aggregates have been determined. The ionic conductivity increases due to the increase of free ions with the increase of propylene carbonate content. But for higher content of propylene carbonate, the ionic conductivity decreases due to the increase of concentrations of ion-pairs and ion-aggregates. To get further insights into the ion dynamics, the experimental data for the complex dielectric permittivity have been studied using Havriliak–Negami function. The variation of relaxation time with temperature obtained from this formalism follows Vogel-Tamman-Fulcher equation similar to the ionic conductivity.

  17. A study on the identification of cognitive complexity factors related to the complexity of procedural steps

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Kyun; Jeong, Kwang Sup; Jung, Won Dea [KAERI, Taejon (Korea, Republic of)

    2004-07-01

    In complex systems, it is well recognized that the provision of understandable procedures that allow operators to clarify 'what needs to be done' and 'how to do it' is one of the requisites to confirm their safety. In this regard, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is evinced from the comparisons between SC scores and operators' performance data. To this end, the comparisons between operators' performance data with their behavior in conducting prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect operators' cognitive burden are identified. Although a well-designed experiment is indispensable in confirming the appropriateness of cognitive complexity factors, it is strongly believed that the change of an operator's performance can be more authentically explained if they are taken into consideration.

  18. A study on the identification of cognitive complexity factors related to the complexity of procedural steps

    International Nuclear Information System (INIS)

    Park, Jin Kyun; Jeong, Kwang Sup; Jung, Won Dea

    2004-01-01

    In complex systems, it is well recognized that the provision of understandable procedures that allow operators to clarify 'what needs to be done' and 'how to do it' is one of the requisites to confirm their safety. In this regard, the step complexity (SC) measure that can quantify the complexity of procedural steps in emergency operating procedures (EOPs) of a nuclear power plant (NPP) was suggested. However, the necessity of additional complexity factors that can consider a cognitive aspect in evaluating the complexity of procedural steps is evinced from the comparisons between SC scores and operators' performance data. To this end, the comparisons between operators' performance data with their behavior in conducting prescribed activities of procedural steps are conducted in this study. As a result, two kinds of complexity factors (the abstraction level of knowledge and the level of engineering decision) that could affect operators' cognitive burden are identified. Although a well-designed experiment is indispensable in confirming the appropriateness of cognitive complexity factors, it is strongly believed that the change of an operator's performance can be more authentically explained if they are taken into consideration

  19. Group 4 Metalloporphyrin diolato Complexes and Catalytic Application of Metalloporphyrins and Related Transition Metal Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Du, Guodong [Iowa State Univ., Ames, IA (United States)

    2003-01-01

    In this work, the first examples of group 4 metalloporphyrin 1,2-diolato complexes were synthesized through a number of strategies. In general, treatment of imido metalloporphyrin complexes, (TTP)M=NR, (M = Ti, Zr, Hf), with vicinal diols led to the formation of a series of diolato complexes. Alternatively, the chelating pinacolate complexes could be prepared by metathesis of (TTP)MCl2 (M = Ti, Hf) with disodium pinacolate. These complexes were found to undergo C-C cleavage reactions to produce organic carbonyl compounds. For titanium porphyrins, treatment of a titanium(II) alkyne adduct, (TTP)Ti(η2-PhC≡CPh), with aromatic aldehydes or aryl ketones resulted in reductive coupling of the carbonyl groups to produce the corresponding diolato complexes. Aliphatic aldehydes or ketones were not reactive towards (TTP)Ti(η2-PhC≡CPh). However, these carbonyl compounds could be incorporated into a diolato complex on reaction with a reactive precursor, (TTP)Ti[O(Ph)2C(Ph)2O] to provide unsymmetrical diolato complexes via cross coupling reactions. In addition, an enediolato complex (TTP)Ti(OCPhCPhO) was obtained from the reaction of (TTP)Ti(η2-PhC≡CPh) with benzoin. Titanium porphyrin diolato complexes were found to be intermediates in the (TTP)Ti=O-catalyzed cleavage reactions of vicinal diols, in which atmospheric oxygen was the oxidant. Furthermore, (TTP)Ti=O was capable of catalyzing the oxidation of benzyl alcohol and α-hydroxy ketones to benzaldehyde and α-diketones, respectively. Other high valent metalloporphyrin complexes also can catalyze the oxidative diol cleavage and the benzyl alcohol oxidation reactions with dioxygen. A comparison of Ti(IV) and Sn(IV) porphyrin chemistry was undertaken. While chelated diolato complexes were invariably obtained for titanium porphyrins on treatment with 1,2-diols, the reaction of vicinal diols with tin porphyrins gave a number of products, including mono

  20. Complexity of Configurators Relative to Integrations and Field of Application

    DEFF Research Database (Denmark)

    Kristjansdottir, Katrin; Shafiee, Sara; Battistello, Loris

    . Moreover, configurators are commonly integrated to various IT systems within companies. The complexity of configurators is an important factor when it comes to performance, development and maintenance of the systems. A direct comparison of the complexity based on the different application...... integrations to other IT systems. The research method adopted in the paper is based on a survey followed with interviews where the unit of analysis is based on operating configurators within a company.......Configurators are applied widely to automate the specification processes at companies. The literature describes the industrial application of configurators supporting both sales and engineering processes, where configurators supporting the engineering processes are described more challenging...

  1. Microfluidic-based Broadband Measurements of Fluid Permittivity and Permeability to 100 GHz

    Science.gov (United States)

    Little, Charles A. E.

    This dissertation concerns the development of unique microfluidic microwave devices and associated microwave calibrations to quantitatively extract the broadband permittivity and permeability of fluids between 100 kHz and 110 GHz. The devices presented here consist of SU-8- and PDMS-based microfluidic channels integrated lithographically with coplanar waveguides (CPWs), measured via an external vector network analyzer (VNA). By applying our hybrid set of microwave calibrations to the raw data we extract distributed circuit parameters, representative of the electromagnetic response of the microfluidic channel. We then correlate these parameters to the permittivity and permeability of the fluid within the channels. We are primarily focused on developing devices, calibrations, and analyses to characterize various chemical and biological systems. The small fluid volumes and overall scale of our devices lends the technique to point-of-care blood and cell analysis, as well as to the analysis of high-value chemicals. Broadband microwave microfluidics is sensitive to three primary categories of phenomena: Ionic, dipolar, and magnetic resonances. All three can occur in complex fluids such as blood, proteins and particle suspensions. In order to make quantitative measurements, we need to be able to model and separate all three types of responses. Here we first measure saline solutions (NaCl and water) as an ideal system to better understanding both the ionic and dipolar response. Specifically, we are targeting the electrical double-layer (EDL) response, an ionic effect, which dominates over the intrinsic fluid response at lower frequencies. We have found that the EDL response for saline obeys a strict Debye-type relaxation model, the frequency response of which is dependent solely on the conductivity of the solution. To develop a better understanding of the magnetic response, we first measure magnetic nanoparticles; showing it is possible to detect the magnetic resonances of

  2. Novel Complexity Indicator of Manufacturing Process Chains and Its Relations to Indirect Complexity Indicators

    Directory of Open Access Journals (Sweden)

    Vladimir Modrak

    2017-01-01

    Full Text Available Manufacturing systems can be considered as a network of machines/workstations, where parts are produced in flow shop or job shop environment, respectively. Such network of machines/workstations can be depicted as a graph, with machines as nodes and material flow between the nodes as links. The aim of this paper is to use sequences of operations and machine network to measure static complexity of manufacturing processes. In this order existing approaches to measure the static complexity of manufacturing systems are analyzed and subsequently compared. For this purpose, analyzed competitive complexity indicators were tested on two different manufacturing layout examples. A subsequent analysis showed relevant potential of the proposed method.

  3. The estimate of permittivity of anisotropic composites with lamellar inclusions by the self-assessment method

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2015-01-01

    Full Text Available Composites are widely used as structural or thermal protection materials; they are used as well as functional materials in a large number of different electrical devices and as dielectrics. This composite has one of the most important characteristics the relative permittivity. It depends primarily on the dielectric properties of the inclusions and the matrix as well as the shape and volume content of the inclusions.In this paper, a mathematical model of the interaction of the electrostatic fields in an isotropic plate and in the surrounding homogeneous anisotropic medium is constructed. This model describes the dielectric properties of the composite with such inclusions. A variant of the same orientation of lamellar inclusions is considered, which leads to the special case of anisotropy of the dielectric properties of the composite that has transverse isotropy towards the direction perpendicular to the inclusions. The shape of inclusions is represented as an oblate ellipsoid of revolution (spheroid. Transformation of the differential equation describing the distribution of the electric potential transversely to isotropic medium surrounding the spheroidal inclusion, to the Laplace equation with the subsequent transition from the initial spheroid to the given ellipsoid of rotation allows us to apply the self-assessment method for the determination of the dielectric properties of the composite. This method equates the result of averaging the perturbation of the electrostatic field in the inclusions and the matrix particles towards the unperturbed fields in the environment to zero.The constructed mathematical model allows us to determine the electrostatic field disturbance in the inclusions and the matrix particles towards the unperturbed field given in the environment at a distance from the inclusions and the matrix particles, much larger than their characteristic dimensions. By averaging the perturbation of the electrostatic field in all the

  4. Relating illness complexity to reimbursement in CKD patients.

    Science.gov (United States)

    Bessette, Russell W; Carter, Randy L

    2011-01-01

    Despite significant investments of federal and state dollars to transition patient medical records to an all-electronic system, a chasm still exists between health care quality and payment for it. A major reason for this gap is the difficulty in evaluating health care outcomes based on claims data. Since both payers and patients may not appreciate how illness complexity impacts treatment outcomes, it is difficult to determine fair provider compensation. Chronic kidney disease (CKD) typifies these problems and is often associated with comorbidities that impact cost, health, and work productivity. Thus, the objective of this study was to evaluate an illness complexity score (ICS) based on a linear regression of select blood values that might assist in predicting average monthly reimbursements in CKD patients. A second objective was to compare the results of this ICS prediction to results obtained by prediction of average monthly reimbursement using CKD stage. A third objective was to analyze the relationship between the change in ICS, estimated glomerular filtration rate (eGFR), and CKD stage over time to average monthly reimbursement. We calculated parsimonious values for select variables associated with CKD patients and compared the ICS to ordinal staging of renal disease. Data from 177 de-identified patients over 13 months was collected, which included 15 blood chemistry observations along with complete claims data for all medical expenses. To test for the relationship between average blood chemistry values, stages of CKD, age, and average monthly reimbursement, we modeled an association through a linear regression function of age, eGFR, and the Z-scores calculated from average monthly values of phosphorus, parathyroid hormone, glucose, hemoglobin, bicarbonate, albumin, creatinine, blood urea nitrogen, potassium, calcium, sodium, alkaline phosphatase, alanine aminotransferase, and white blood cells. The results of our study demonstrated that the association

  5. Qualitative Reasoning about Relative Directions : Computational Complexity and Practical Algorithm

    OpenAIRE

    Lee, Jae Hee

    2013-01-01

    Qualitative spatial reasoning (QSR) enables cognitive agents to reason about space using abstract symbols. Among several aspects of space (e.g., topology, direction, distance) directional information is useful for agents navigating in space. Observers typically describe their environment by specifying the relative directions in which they see other objects or other people from their point of view. As such, qualitative reasoning about relative directions, i.e., determining whether a given stat...

  6. CHANGE MANAGEMENT STRATEGIES RELATED TO THE GLOBAL ENVIRONMENT COMPLEXITY

    Directory of Open Access Journals (Sweden)

    Elena DOVAL

    2016-12-01

    Full Text Available The changes in organizations appear as a reaction to the organizational environment changes. In order to manage these changes successfully, the managers need to anticipate and design alternative strategies by preparing different options.  Nevertheless, the complexity of the global environment forces the managers to adopt strategies for their organizations that are facilitating the creation of new strategic competences and competitive advantages to face the environmental rapid changes. In this context, this paper is aiming to illustrate the main directions the change management may consider to change the organization strategies in order to harmonize them to the external environment, such as: integration versus externalization, flexible specialization and flexible organization, standardization versus adaptation, market segmentation, relationship building and maintaining and communication integration.  However, the new strategies are based on a changed attitude of the managers towards the competitive advantage that is dynamic and focused on creation rather then to operations.

  7. Relating illness complexity to reimbursement in CKD patients

    Directory of Open Access Journals (Sweden)

    Bessette RW

    2011-09-01

    Full Text Available Russell W Bessette1, Randy L Carter2,3 1Department of Health Sciences, Institute for Healthcare Informatics, 2Department of Biostatistics, 3Population Health Observatory, University at Buffalo, State University of New York, Buffalo, NY, USA Background: Despite significant investments of federal and state dollars to transition patient medical records to an all-electronic system, a chasm still exists between health care quality and payment for it. A major reason for this gap is the difficulty in evaluating health care outcomes based on claims data. Since both payers and patients may not appreciate how illness complexity impacts treatment outcomes, it is difficult to determine fair provider compensation. Objectives: Chronic kidney disease (CKD typifies these problems and is often associated with comorbidities that impact cost, health, and work productivity. Thus, the objective of this study was to evaluate an illness complexity score (ICS based on a linear regression of select blood values that might assist in predicting average monthly reimbursements in CKD patients. A second objective was to compare the results of this ICS prediction to results obtained by prediction of average monthly reimbursement using CKD stage. A third objective was to analyze the relationship between the change in ICS, estimated glomerular filtration rate (eGFR, and CKD stage over time to average monthly reimbursement. Methods: We calculated parsimonious values for select variables associated with CKD patients and compared the ICS to ordinal staging of renal disease. Data from 177 de-identified patients over 13 months was collected, which included 15 blood chemistry observations along with complete claims data for all medical expenses. To test for the relationship between average blood chemistry values, stages of CKD, age, and average monthly reimbursement, we modeled an association through a linear regression function of age, eGFR, and the Z-scores calculated from average

  8. Electrical studies of Fe-related defect complexes in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chi Kwong

    2012-09-15

    Iron (Fe) is an important impurity in solar-grade silicon which contributes substantially in degrading the efficiency of solar cells. The degradation is mainly caused by the Fe atoms situating at an unperturbed tetrahedral interstitial sites (Fei) in the silicon crystal, consequently acting as a recombination center. By altering the position and the neighbouring environment at which the Fe atoms reside, there are opportunities in minimizing or neutralizing the electrical activity of Fe. Furthermore, utilizing the high mobility of Fe, one can increase the performance of a device by accumulating the Fe atoms from critical regions into regions where Fe can be tolerated. These approaches can help in realizing high efficient solar cells based on cheap and highly Fe-contaminated silicon. In this work, we have investigated the interaction between Fe and defects relevant to solar cells, using mainly electrical characterization methods such as capacitance-voltage measurement, deep level transient spectroscopy and admittance spectroscopy. From the study of potential hydrogen passivation of Fe, hydrogen was introduced through wet chemical etching and further driven to a defined region. Using depth profiles, it is found that incorporation of hydrogen stimulates the dissociation of the iron-boron (Fe-B) pair, releasing and resulting in the unwanted Fei. At the same time, no passivation of Fe by hydrogen has been observed. On the investigation of the mechanism of phosphorus gettering of metal impurities, vacancies have been generated through proton-irradiation. The resulting irradiation-induced defects were examined for reactions with Fe after heat treatments. Based on the evolution of defect concentrations by isochronal annealings, it is found that Fe interacts with the divacancy and the vacancy-oxygen complexes, forming deep levels of 0.28 eV and 0.34 eV above the valence band edge (EV), respectively. In the search for substitutional Fe to investigate its electrical activity

  9. Homogenization via the strong-permittivity-fluctuation theory with nonzero depolarization volume

    Science.gov (United States)

    Mackay, Tom G.

    2004-08-01

    The depolarization dyadic provides the scattering response of a single inclusion particle embedded within a homogenous background medium. These dyadics play a central role in formalisms used to estimate the effective constitutive parameters of homogenized composite mediums (HCMs). Conventionally, the inclusion particle is taken to be vanishingly small; this allows the pointwise singularity of the dyadic Green function associated with the background medium to be employed as the depolarization dyadic. A more accurate approach is pursued in this communication by taking into account the nonzero spatial extent of inclusion particles. Depolarization dyadics corresponding to inclusion particles of nonzero volume are incorporated within the strong-permittivity-fluctuation theory (SPFT). The linear dimensions of inclusion particles are assumed to be small relative to the electromagnetic wavelength(s) and the SPFT correlation length. The influence of the size of inclusion particles upon SPFT estimates of the HCM constitutive parameters is investigated for anisotropic dielectric HCMs.In particular, the interplay between correlation length and inclusion size is explored.

  10. The permittivity and refractive index measurements of doped barium titanate (BT-BCN)

    Science.gov (United States)

    Meeker, Michael A.; Kundu, Souvik; Maurya, Deepam; Kang, Min-Gyu; Sosa, Alejandro; Mudiyanselage, Rathsara R. H. H.; Clavel, Michael; Gollapudi, Sreenivasulu; Hudait, Mantu K.; Priya, Shashank; Khodaparast, Giti A.

    2017-11-01

    While piezoelectric- ferroelectric materials offer great potential for nonvolatile random access memory, most commonly implemented ferroelectrics contain lead which imposes a challenge in meeting environmental regulations. One promising candidate for lead-free, ferroelectric material based memory is (1 - x) BaTiO3 - xBa(Cu1 / 3 Nb2 / 3) O3 (BT-BCN), x = 0.025 . The samples studied here were grown on a Si substrate with an HfO2 buffer layer, thereby preventing the interdiffusion of BT-BTCN into Si. This study provides further insight into the physical behavior of BT-BCN that will strengthen the foundation for developing switching devices. The sample thicknesses ranged from 1.5 to 120 nm, and piezoelectric force microscopy was employed in order to understand the local ferroelectric behaviors. Dielectric constant as a function of frequency demonstrated enhanced frequency dispersion indicating the polar nature of the composition. The relative permittivity was found to change significantly with varying bias voltage and exhibited a tunability of 82%. The difference in the peak position during up and down sweeps is due to the presence of the spontaneous polarization. Furthermore, reflectometry was performed to determine the refractive index of samples with differing thicknesses. Our results demonstrate that refractive indices are similar to that of barium titanate. This is a promising result indicating that improved ferroelectric properties are obtained without compromising the optical properties.

  11. Improving dielectric permittivity by incorporating PDMS-PEG block copolymer into PDMS network

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Szabo, Peter; Skov, Anne Ladegaard

    Polydimethylsiloxane (PDMS) based elastomers are well-known to actuate with large strain mainly due to their low modulus and their non-conducting nature. On the other hand, polyethyleneglycols(PEG) are not stretchable but they have high permittivity and are conductive. Combination of the two...... polymers as a block copolymer depicts a possibility for substantial improvement of properties such as high permittivity and non-conductivity – if carefully designed. The objective is to synthesize PDMS-PEG multiblock copolymer assembling into different morphologies1 such as lamellar,cylinder, gyroid...... and spheres based on variation of volume fractions of PDMS and PEG. The synthesisis amended from Klasner et al.2 and Jukarainen et al.3 Variation in the ratio between the two constituents introduces distinctive properties in terms of dielectric permittivity and rheological behaviour. PDMS-PEG multiblock...

  12. Realizability of metamaterials with prescribed electric permittivity and magnetic permeability tensors

    International Nuclear Information System (INIS)

    Milton, Graeme W

    2010-01-01

    We show that any pair of real symmetric tensors ε and μ can be realized as the effective electric permittivity and effective magnetic permeability of a metamaterial at a given fixed frequency. The construction starts with two extremely low-loss metamaterials, with arbitrarily small microstructure, whose existence is ensured by the work of Bouchitte and Bourel and Bouchitte and Schweizer: one having, at the given frequency, a permittivity tensor with exactly one negative eigenvalue, and a positive permeability tensor; and the other having a positive permittivity tensor, and a permeability tensor having exactly one negative eigenvalue. To achieve the desired effective properties, these materials are laminated together in a hierarchical multiple rank laminate structure, with widely separated length scales, and varying directions of lamination, but with the largest length scale still much shorter than the wavelengths and attenuation lengths in the macroscopic effective medium.

  13. Studies of permittivity and permeability of dielectric matrix with cuboid metallic inclusions in different orientations

    Directory of Open Access Journals (Sweden)

    W. M. Wu

    2014-10-01

    Full Text Available In this paper, we investigate the possibility of using the heterogeneous materials, with cuboid metallic inclusions inside a dielectric substrate (host to control the effective permittivity. We find that in the gigahertz range, such a material demonstrates a significantly larger permittivity compared to the pure dielectric substrate. Three principal orientations of microscale cuboid inclusions have been taken into account in this study. The highest permittivity is observed when the orientation provides the largest polarization (electric dipole moment. The detrimental side effect of the metallic inclusion, which leads to the decrease of the effective magnetic permeability, can be suppressed by the proper choice of shape and orientation of the inclusions. This choice can in fact reduce the induced current and hence maximize the permeability. The dissipative losses are shown to be negligible in the relevant range of frequencies and cuboid dimensions.

  14. Exponential model normalization for electrical capacitance tomography with external electrodes under gap permittivity conditions

    International Nuclear Information System (INIS)

    Baidillah, Marlin R; Takei, Masahiro

    2017-01-01

    A nonlinear normalization model which is called exponential model for electrical capacitance tomography (ECT) with external electrodes under gap permittivity conditions has been developed. The exponential model normalization is proposed based on the inherently nonlinear relationship characteristic between the mixture permittivity and the measured capacitance due to the gap permittivity of inner wall. The parameters of exponential equation are derived by using an exponential fitting curve based on the simulation and a scaling function is added to adjust the experiment system condition. The exponential model normalization was applied to two dimensional low and high contrast dielectric distribution phantoms by using simulation and experimental studies. The proposed normalization model has been compared with other normalization models i.e. Parallel, Series, Maxwell and Böttcher models. Based on the comparison of image reconstruction results, the exponential model is reliable to predict the nonlinear normalization of measured capacitance in term of low and high contrast dielectric distribution. (paper)

  15. A simple method for reducing inevitable dielectric loss in high-permittivity dielectric elastomers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Mazurek, Piotr Stanislaw

    2016-01-01

    elastomer matrix, with high dielectric permittivity and a low Young's modulus, aligned with no loss of mechanical stability, was prepared through the use of commercially available chloropropyl-functional silicone oil mixed into a tough commercial liquid silicone rubber silicone elastomer. The addition...... also decreased the dielectric losses of an elastomer containing dielectric permittivity-enhancing TiO2 fillers. Commercially available chloropropyl-functional silicone oil thus constitutes a facile method for improved silicone DEs, with very low dielectric losses.......Commercial viability of dielectric elastomers (DEs) is currently limited by a few obstacles, including high driving voltages (in the kV range). Driving voltage can be lowered by either decreasing the Young's modulus or increasing the dielectric permittivity of silicone elastomers, or a combination...

  16. Modeled effects on permittivity measurements of water content in high surface area porous media

    International Nuclear Information System (INIS)

    Jones, S.B.; Or, Dani

    2003-01-01

    Time domain reflectometry (TDR) has become an important measurement technique for determination of porous media water content and electrical conductivity due to its accuracy, fast response and automation capability. Water content is inferred from the measured bulk dielectric constant based on travel time analysis along simple transmission lines. TDR measurements in low surface area porous media accurately describe water content using an empirical relationship. Measurement discrepancies arise from dominating influences such as bound water due to high surface area, extreme aspect ratio particles or atypical water phase configuration. Our objectives were to highlight primary factors affecting dielectric permittivity measurements for water content determination in porous mixtures, and demonstrate the influence of these factors on mixture permittivity as predicted by a three-phase dielectric mixture model. Modeled results considering water binding, higher porosity, constituent geometry or phase configuration suggest any of these effects individually are capable of causing permittivity reduction, though all likely contribute in high surface area porous media

  17. Plasmonic modulator optimized by patterning of active layer and tuning permittivity

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Lavrinenko, Andrei

    2012-01-01

    as electrodes. External field changes carrier density in the ultra-thin ITO layer, which influences the permittivity. The metal-insulator-metal system possesses a plasmon resonance, and it is strongly affected by changes in the permittivity of the active layer. To improve performance of the structure we propose...... several optimizations. We examine influence of the ITO permittivity on the modulator's performance and point out appropriate values. We analyze eigenmodes of the waveguide structure and specify the range for its efficient operation. We show that substituting the continuous active layer by a one......-dimension periodic stripes increases transmittance through the device and keeps the modulator's performance at the same level. The dependence on the pattern size and filling factor of the active material is analyzed and optimum parameters are found. Patterned ITO layers allow us to design a Bragg grating inside...

  18. Theoretical and Experimental Study on the Permittivity of CdTe in the Terahertz Band

    Directory of Open Access Journals (Sweden)

    Sun Wang

    2018-02-01

    Full Text Available The phonon dispersion spectrum, eigenvector, and lattice vibration frequency of cadmium telluride with a zinc blende structure have been investigated using the density functional theory, and the permittivity of cadmium telluride crystal is numerically calculated. The permittivity of the crystal is measured using the terahertz time-domain spectroscopy system. The experimental results are consistent with the theoretical calculations on the modified local density approximation, the general gradient approximation, and the modified general gradient approximation. Finally, the differences among the three approximate exchange correlation potentials indicate that in the terahertz region, the permittivity of cadmium telluride is dominantly contributed by the coupling between electron and phonon; however, the phonon frequencies of transverse wave and longitudinal wave were sensitive to electron density distribution.

  19. Dielectric elastomers, with very high dielectric permittivity, based on silicone and ionic interpenetrating networks

    DEFF Research Database (Denmark)

    Yu, Liyun; Madsen, Frederikke Bahrt; Hvilsted, Søren

    2015-01-01

    permittivity and the Young's modulus of the elastomer. One system that potentially achieves this involves interpenetrating polymer networks (IPNs), based on commercial silicone elastomers and ionic networks from amino- and carboxylic acid-functional silicones. The applicability of these materials as DEs...... are obtained while dielectric breakdown strength and Young's modulus are not compromised. These good overall properties stem from the softening effect and very high permittivity of ionic networks – as high as ε′ = 7500 at 0.1 Hz – while the silicone elastomer part of the IPN provides mechanical integrity...

  20. Role of doping and CuO segregation in improving the giant permittivity of CaCu3Ti4O12

    International Nuclear Information System (INIS)

    Capsoni, D.; Bini, M.; Massarotti, V.; Chiodelli, G.; Mozzatic, M.C.; Azzoni, C.B.

    2004-01-01

    The dopant role on the electric and dielectric properties of the perovskite-type CaCu 3 Ti 4 O 12 (CCTO) compound is evidenced. Impedance spectroscopy measurements show that the relevant permittivity value attributed to sintered CCTO is due to grain boundary (g.b.) effects. The g.b. permittivity value of the pure CCTO can be increased of 1-2 orders of magnitude by cation substitution on Ti site and/or segregation of CuO phase, while the bulk permittivity keeps values 90εr180. Bulk and g.b. conductivity contributions are discussed: electrons are responsible for the charge transport and a mean bulk activation energy of 0.07eV is obtained at room temperature for all the examined samples. The g.b. activation energy ranges between 0.54 and 0.76eV. Defect models related to the transport properties are proposed, supported by electron paramagnetic resonance measurements

  1. Complexities in euthanasia or physician-assisted suicide as perceived by Dutch physicians and patients' relatives.

    Science.gov (United States)

    Snijdewind, Marianne C; van Tol, Donald G; Onwuteaka-Philipsen, Bregje D; Willems, Dick L

    2014-12-01

    The practice of euthanasia and physician-assisted suicide (EAS) is always complex, but some cases are more complex than others. The nature of these unusually complex cases is not known. To identify and categorize the characteristics of EAS requests that are more complex than others. We held in-depth interviews with 28 Dutch physicians about their perception of complex cases of EAS requests. We also interviewed 26 relatives of patients who had died by EAS. We used open coding and inductive analysis to identify various different aspects of the complexities described by the participants. Complexities can be categorized into relational difficulties-such as miscommunication, invisible suffering, and the absence of a process of growth toward EAS-and complexities that arise from unexpected situations, such as the capricious progress of a disease or the obligation to move the patient. The interviews showed that relatives of the patient influence the process toward EAS. First, the process toward EAS may be disrupted, causing a complex situation. Second, the course of the process toward EAS is influenced not only by the patient and his/her attending physician but also by the relatives who are involved. Communicating and clarifying expectations throughout the process may help to prevent the occurrence of unusually complex situations. Copyright © 2014 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  2. Probing the negative permittivity perfect lens at optical frequencies using near-field optics and single molecule detection

    NARCIS (Netherlands)

    Moerland, R.J.; van Hulst, N.F.; Gersen, H.; Kuipers, L.

    2005-01-01

    Recently, the existence of a perfect lens has been predicted, made of an artificial material that has a negative electric permittivity and a negative magnetic permeability. For optical frequencies a poormans version is predicted to exist in the sub-wavelength limit. Then, only the permittivity has

  3. On the definition of dielectric permittivity for media with temporal dispersion in the presence of free charge carriers

    International Nuclear Information System (INIS)

    Bordag, M; Geyer, B; Klimchitskaya, G L; Mostepanenko, V M

    2010-01-01

    We show that in the presence of free charge carriers the definition of the frequency-dependent dielectric permittivity requires additional regularization. As an example, the dielectric permittivity of the Drude model is considered and its time-dependent counterpart is derived and analyzed. The respective electric displacement cannot be represented in terms of the standard Fourier integral. The regularization procedure allowing the circumvention of these difficulties is suggested. For the purpose of comparison it is shown that the frequency-dependent dielectric permittivity of insulators satisfies all rigorous mathematical criteria. This permits us to conclude that in the presence of free charge carriers the concept of dielectric permittivity is not as well defined as for insulators and we make a link to widely discussed puzzles in the theory of thermal Casimir force which might be caused by the use of this kind of permittivities.

  4. On the definition of dielectric permittivity for media with temporal dispersion in the presence of free charge carriers

    Energy Technology Data Exchange (ETDEWEB)

    Bordag, M; Geyer, B; Klimchitskaya, G L; Mostepanenko, V M [Institute for Theoretical Physics, Leipzig University, Postfach 100920, D-04009, Leipzig (Germany)

    2010-01-08

    We show that in the presence of free charge carriers the definition of the frequency-dependent dielectric permittivity requires additional regularization. As an example, the dielectric permittivity of the Drude model is considered and its time-dependent counterpart is derived and analyzed. The respective electric displacement cannot be represented in terms of the standard Fourier integral. The regularization procedure allowing the circumvention of these difficulties is suggested. For the purpose of comparison it is shown that the frequency-dependent dielectric permittivity of insulators satisfies all rigorous mathematical criteria. This permits us to conclude that in the presence of free charge carriers the concept of dielectric permittivity is not as well defined as for insulators and we make a link to widely discussed puzzles in the theory of thermal Casimir force which might be caused by the use of this kind of permittivities.

  5. High dielectric permittivity elastomers from well-dispersed expanded graphite in low concentrations

    DEFF Research Database (Denmark)

    Daugaard, Anders Egede; Hassouneh, Suzan Sager; Kostrzewska, Malgorzata

    2013-01-01

    The development of elastomer materials with a high dielectric permittivity has attracted increased interest over the last years due to their use in for example dielectric electroactive polymers. For this particular use, both the electrically insulating properties - as well as the mechanical...

  6. EBG structures on high permittivity substrate to reduce noise in power distribution networks

    NARCIS (Netherlands)

    Tereshchenko, O.V.; Buesink, Frederik Johannes Karel; Leferink, Frank Bernardus Johannes

    2012-01-01

    The noise reduction effect in a Power Distribution Network (PDN) by implementing Electromagnetic Band Gap structures (EBG) on standard and high permittivity substrates has been investigated. Boards with different EBG structures have been modelled and designed. Using the EBG structures the Power

  7. Divergence of dielectric permittivity near phase transition within ferroelectric domain boundaries

    Czech Academy of Sciences Publication Activity Database

    Márton, Pavel; Stepkova, Vilgelmina; Hlinka, Jiří

    2013-01-01

    Roč. 86, č. 1 (2013), s. 103-108 ISSN 0141-1594 R&D Projects: GA ČR GAP204/10/0616 Institutional support: RVO:68378271 Keywords : Bloch wall * domain boundary * BaTiO 3 * Ginzburg-Landau-Devonshire theory * permittivity Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.044, year: 2013

  8. 2 filler on the dielectric permittivity and electrical modulus of PMMA

    Indian Academy of Sciences (India)

    The real and imaginary part of the dielectric permittivity decreased with the increase in frequency but increased with temperature. The electrical conductivity measurement showed a plateau-like behaviour in the low-frequency region and dispersion in the high-frequency region. The frequency-dependent electrical modulus ...

  9. Microstructure-based numerical modeling method for effective permittivity of ceramic/polymer composites

    Science.gov (United States)

    Jylhä, Liisi; Honkamo, Johanna; Jantunen, Heli; Sihvola, Ari

    2005-05-01

    Effective permittivity was modeled and measured for composites that consist of up to 35vol% of titanium dioxide powder dispersed in a continuous epoxy matrix. The study demonstrates a method that enables fast and accurate numerical modeling of the effective permittivity values of ceramic/polymer composites. The model requires electrostatic Monte Carlo simulations, where randomly oriented homogeneous prism-shaped inclusions occupy random positions in the background phase. The computation cost of solving the electrostatic problem by a finite-element code is decreased by the use of an averaging method where the same simulated sample is solved three times with orthogonal field directions. This helps to minimize the artificial anisotropy that results from the pseudorandomness inherent in the limited computational domains. All the required parameters for numerical simulations are calculated from the lattice structure of titanium dioxide. The results show a very good agreement between the measured and numerically calculated effective permittivities. When the prisms are approximated by oblate spheroids with the corresponding axial ratio, a fairly good prediction for the effective permittivity of the mixture can be achieved with the use of an advanced analytical mixing formula.

  10. Silicone elastomers with high dielectric permittivity and high dielectric breakdown strength based on tunable functionalized copolymers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Daugaard, Anders Egede

    2015-01-01

    system, with respect to functionalization, is achieved. It is investigated how the different functionalization variables affect essential DE properties, including dielectric permittivity, dielectric loss, elastic modulus and dielectric breakdown strength, and the optimal degree of chemical......%) was obtained without compromising other vital DE properties such as elastic modulus, gel fraction, dielectric and viscous loss and electrical breakdown strength....

  11. Silicone elastomers with high dielectric permittivity and high dielectric breakdown strength based on dipolar copolymers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Daugaard, Anders Egede

    2014-01-01

    Dielectric elastomers (DES) are a promising new transducer technology, but high driving voltages limit their current commercial potential. One method used to lower driving voltage is to increase dielectric permittivity of the elastomer. A novel silicone elastomer system with high dielectric...

  12. [Patient-related complexity in nursing care - Collective case studies in the acute care hospital].

    Science.gov (United States)

    Gurtner, Caroline; Spirig, Rebecca; Staudacher, Diana; Huber, Evelyn

    2018-06-04

    Patient-related complexity in nursing care - Collective case studies in the acute care hospital Abstract. Patient-related complexity of nursing is defined by the three characteristics "instability", "uncertainty", and "variability". Complexity increased in the past years, due to reduced hospital length of stay and a growing number of patients with chronic and multiple diseases. We investigated the phenomenon of patient-related complexity from the point of view of nurses and clinical nurse specialists in an acute care hospital. In the context of a collective case study design, nurses and clinical nurse specialists assessed the complexity of nursing situations with a questionnaire. Subsequently, we interviewed nurses and clinical nurse specialists about their evaluation of patient-related complexity. In a within-case-analysis we summarized data inductively to create case narratives. By means of a cross-case-analysis we compared the cases with regard to deductively derived characteristics. The four cases exemplarily showed that the degree of complexity depends on the controllability and predictability of clinical problems. Additionally, complexity increases or decreases, according to patients' individual resources. Complex patient situations demand professional expertise, experience, communicative competencies and the ability for reflection. Beginner nurses would benefit from support and advice by experienced nurses to develop these skills.

  13. The development and application of composite complexity models and a relative complexity metric in a software maintenance environment

    Science.gov (United States)

    Hops, J. M.; Sherif, J. S.

    1994-01-01

    A great deal of effort is now being devoted to the study, analysis, prediction, and minimization of software maintenance expected cost, long before software is delivered to users or customers. It has been estimated that, on the average, the effort spent on software maintenance is as costly as the effort spent on all other software costs. Software design methods should be the starting point to aid in alleviating the problems of software maintenance complexity and high costs. Two aspects of maintenance deserve attention: (1) protocols for locating and rectifying defects, and for ensuring that noe new defects are introduced in the development phase of the software process; and (2) protocols for modification, enhancement, and upgrading. This article focuses primarily on the second aspect, the development of protocols to help increase the quality and reduce the costs associated with modifications, enhancements, and upgrades of existing software. This study developed parsimonious models and a relative complexity metric for complexity measurement of software that were used to rank the modules in the system relative to one another. Some success was achieved in using the models and the relative metric to identify maintenance-prone modules.

  14. Complexity Triggered by Economic Globalisation— The Issue of On-Line Betting-Related Match Fixing

    OpenAIRE

    Wladimir Andreff

    2017-01-01

    Complexity in mainstream economics consists in high intermediary consumption of mathematics. A new approach to complexity economics dwells upon path-dependent global systems; their emergence and evolving organisation. The focus here is on the complexity of the real economic world due to globalisation. On-line betting related match-fixing is a case in point about which the article presents non-exhaustive empirical evidence and shows how it is analysed with the standard model of the economics o...

  15. Flexible Ultrahigh-Temperature Polymer-Based Dielectrics with High Permittivity for Film Capacitor Applications

    Directory of Open Access Journals (Sweden)

    Zejun Pu

    2017-11-01

    Full Text Available In this report, flexible cross-linked polyarylene ether nitrile/functionalized barium titanate(CPEN/F-BaTiO3 dielectrics films with high permittivitywere prepared and characterized. The effects of both the F-BaTiO3 and matrix curing on the mechanical, thermal and dielectric properties of the CPEN/F-BaTiO3 dielectric films were investigated in detail. Compared to pristine BaTiO3, the surface modified BaTiO3 particles effectively improved their dispersibility and interfacial adhesion in the polymer matrix. Moreover, the introduction of F-BaTiO3 particles enhanced dielectric properties of the composites, with a relatively high permittivity of 15.2 and a quite low loss tangent of 0.022 (1 kHz when particle contents of 40 wt % were utilized. In addition, the cyano (–CN groups of functional layer also can serve as potential sites for cross-linking with polyarylene ether nitrile terminated phthalonitrile (PEN-Ph matrix and make it transform from thermoplastic to thermosetting. Comparing with the pure PEN-ph film, the latter results indicated that the formation of cross-linked network in the polymer-based system resulted in increased tensile strength by ~67%, improved glass transition temperature (Tg by ~190 °C. More importantly, the CPEN/F-BaTiO3 composite films filled with 30 wt % F-BaTiO3 particles showed greater energy density by nearly 190% when compared to pure CPEN film. These findings enable broader applications of PEN-based composites in high-performance electronics and energy storage devices materials used at high temperature.

  16. Using Complex Auditory-Visual Samples to Produce Emergent Relations in Children with Autism

    Science.gov (United States)

    Groskreutz, Nicole C.; Karsina, Allen; Miguel, Caio F.; Groskreutz, Mark P.

    2010-01-01

    Six participants with autism learned conditional relations between complex auditory-visual sample stimuli (dictated words and pictures) and simple visual comparisons (printed words) using matching-to-sample training procedures. Pre- and posttests examined potential stimulus control by each element of the complex sample when presented individually…

  17. The Complex Trauma Questionnaire (ComplexTQ:Development and preliminary psychometric properties of an instrument for measuring early relational trauma

    Directory of Open Access Journals (Sweden)

    Carola eMaggiora Vergano

    2015-09-01

    Full Text Available Research on the etiology of adult psychopathology and its relationship with childhood trauma has focused primarily on specific forms of maltreatment. This study developed an instrument for the assessment of childhood and adolescence trauma that would aid in identifying the role of co-occurring childhood stressors and chronic adverse conditions. The Complex Trauma Questionnaire (ComplexTQ, in both clinician and self-report versions, is a measure for the assessment of multi-type maltreatment: physical, psychological, and sexual abuse; physical and emotional neglect as well as other traumatic experiences, such rejection, role reversal, witnessing domestic violence, separations, and losses. The four-point Likert scale allows to specifically indicate with which caregiver the traumatic experience has occurred. A total of 229 participants, a sample of 79 nonclinical and that of 150 high-risk and clinical participants, were assessed with the ComplexTQ clinician version applied to Adult Attachment Interview (AAI transcripts. Initial analyses indicate acceptable inter-rater reliability. A good fit to a 6-factor model regarding the experience with the mother and to a 5-factor model with the experience with the father was obtained; the internal consistency of factors derived was good. Convergent validity was provided with the AAI scales. ComplexTQ factors discriminated normative from high-risk and clinical samples. The findings suggest a promising, reliable, and valid measurement of early relational trauma that is reported; furthermore, it is easy to complete and is useful for both research and clinical practice.

  18. Novel Behavioral and Neural Evidences for Age-Related changes in Force complexity.

    Science.gov (United States)

    Chen, Yi-Ching; Lin, Linda L; Hwang, Ing-Shiou

    2018-02-17

    This study investigated age-related changes in behavioral and neural complexity for a polyrhythmic movement, which appeared to be an exception to the loss of complexity hypothesis. Young (n = 15; age = 24.2 years) and older (15; 68.1 years) adults performed low-level force-tracking with isometric index abduction to couple a compound sinusoidal target. Multi-scale entropy (MSE) of tracking force and inter-spike interval (ISI) of motor unit (MU) in the first dorsal interosseus muscle were assessed. The MSE area of tracking force at shorter time scales of older adults was greater (more complex) than that of young adults, whereas an opposite trend (less complex for the elders) was noted at longer time scales. The MSE area of force fluctuations (the stochastic component of the tracking force) were generally smaller (less complex) for older adults. Along with greater mean and coefficient of ISI, the MSE area of the cumulative discharge rate of elders tended to be lower (less complex) than that of young adults. In conclusion, age-related complexity changes in polyrhythmic force-tracking depended on the time scale. The adaptive behavioral consequences could be multi-factorial origins of the age-related impairment in rate coding, increased discharge noises, and lower discharge complexity of pooled MUs.

  19. Cosmochemical implications of CONSERT permittivity characterization of 67P/C-G

    Science.gov (United States)

    Levasseur-Regourd, A.; Hérique, Alain; Kofman, Wlodek; Beck, Pierre; Bonal, Lydie; Buttarazzi, Ilaria; Heggy, Essam; Lasue, Jeremie; Quirico, Eric; Zine, Sonia

    2016-10-01

    Unique information about the internal structure of the nucleus of comet 67P/C-G was provided by the CONSERT bistatic radar on-board Rosetta and Philae [1]. Analysis of the propagation of its signal throughout the small lobe indicated that the real part of the permittivity at 90 MHz is of (1.27±0.05). The first interpretation of this value using dielectric properties of mixtures of dust and ices (H2O, CO2), led to the conclusion that the comet porosity ranges between 75-85%. In addition, the dust/ice ratio was found to range between 0.4-2.6 and the permittivity of dust (including 30% of porosity) was determined to be lower than 2.9.The dust permittivity estimate is now reduced by taking into account the updated values of nucleus density and of dust/ice ratio, in order of providing further insights into the nature of the constituents of comet 67P/C-G [2]. We adopt a systematic approach: i) determination of the dust permittivity as a function of the ice (I) to dust (D) and vacuum (V) volume fraction; ii) comparison with the permittivity of meteoritic, mineral and organic materials from literature and laboratory measurements; iii) test of several composition models of the nucleus, corresponding to cosmochemical end members of 67P/C-G. For each of these models the location in the ternary I/D/V diagram is calculated based on available dielectric measurements, and confronted to the locus of 67P/C-G. The number of compliant models is small and the cosmochemical implications of each are discussed [2]. An important fraction of carbonaceous material is required in the dust in order to match CONSERT permittivity observations, establishing that comets represent a massive carbon reservoir.Support from Centre National d'Études Spatiales (CNES, France) for this work, based on observations with CONSERT on board Rosetta, is acknowledged. The CONSERT instrument was designed, built and operated by IPAG, LATMOS and MPS and was financially supported by CNES, CNRS, UJF/UGA, DLR and MPS

  20. Nonlinear permittivity spectra of supercooled ionic liquids: Observation of a "hump" in the third-order permittivity spectra and comparison to double-well potential models.

    Science.gov (United States)

    Patro, L N; Burghaus, O; Roling, B

    2017-04-21

    We have measured the third-order permittivity spectra ε 3 3 of a monocationic and of a dicationic liquid close to the glass transition temperature by applying ac electric fields with large amplitudes up to 180 kV/cm. A peak ("hump") in the modulus of ε 3 3 is observed for a mono-cationic liquid after subtraction of the dc contribution from the imaginary part of ε 3 3 . We show that the origin of this experimental "hump" is a peak in the imaginary part of ε 3 3 , with the peak height strongly increasing with decreasing temperature. Overall, the spectral shape of the third-order permittivity of both ionic liquids is similar to the predictions of a symmetric double well potential model, although this model does not predict a "hump" in the modulus. In contrast, an asymmetric double well potential model predicts a "hump," but the spectral shape of both the real and imaginary part of ε 3 3 deviates significantly from the experimental spectra. These results show that not only the modulus of ε 3 3 but also its phase is an important quantity when comparing experimental results with theoretical predictions.

  1. Structurally related hydrazone-based metal complexes with different antitumor activities variably induce apoptotic cell death.

    Science.gov (United States)

    Megger, Dominik A; Rosowski, Kristin; Radunsky, Christian; Kösters, Jutta; Sitek, Barbara; Müller, Jens

    2017-04-05

    Three new complexes bearing the tridentate hydrazone-based ligand 2-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)pyridine (L) were synthesized and structurally characterized. Biological tests indicate that the Zn(ii) complex [ZnCl 2 (L)] is of low cytotoxicity against the hepatocellular carcinoma cell line HepG2. In contrast, the Cu(ii) and Mn(ii) complexes [CuCl 2 (L)] and [MnCl 2 (L)] are highly cytotoxic with EC 50 values of 1.25 ± 0.01 μM and 20 ± 1 μM, respectively. A quantitative proteome analysis reveals that treatment of the cells with the Cu(ii) complex leads to a significantly altered abundance of 102 apoptosis-related proteins, whereas 38 proteins were up- or down-regulated by the Mn(ii) complex. A closer inspection of those proteins regulated only by the Cu(ii) complex suggests that the superior cytotoxic activity of this complex is likely to be related to an initiation of the caspase-independent cell death (CICD). In addition, an increased generation of reactive oxygen species (ROS) and a strong up-regulation of proteins responsive to oxidative stress suggest that alterations of the cellular redox metabolism likely contribute to the cytotoxicity of the Cu(ii) complex.

  2. The effects of annealing temperature on the permittivity and electromagnetic attenuation performance of reduced graphene oxide

    Science.gov (United States)

    Wu, Fan; Zeng, Qiao; Xia, Yilu; Sun, Mengxiao; Xie, Aming

    2018-05-01

    Reduced graphene oxide (RGO) has been prepared through the thermal reduction method with different annealing temperatures to explore the effects of temperature on the permittivity and electromagnetic attenuation performance. The real and imaginary parts of permittivity increase along with the decrease in the oxygen functional group and the increase in the filler loading ratio. A composite only loaded with 1 wt. % of RGO can possess an effective electromagnetic absorption bandwidth of 7.60 GHz, when graphene oxide was reduced under 300 °C for 2 h. With the annealing temperature increased to 700 °C and the well reduced RGO loaded 7 wt. % in the composite, the electromagnetic interference shielding efficiency can get higher than 35 dB from 2 to 18 GHz. This study shows that controlling the oxygen functional groups on the RGO surface can also obtain an ideal electromagnetic attenuation performance without any other decorated nanomaterials.

  3. Low frequency modelling of hysteresis behaviour and dielectric permittivity in ferroelectric ceramics under electric field

    International Nuclear Information System (INIS)

    Ducharne, B; Guyomar, D; Sebald, G

    2007-01-01

    The properties of ferroelectric ceramics strongly depend on the electromechanical loading and their measurement conditions. In this paper, a nonlinear phenomenological one-dimensional model based on the dry friction concept is presented to describe the hysteretic polarization behaviour. Dielectric permittivities versus dc electric field (or capacitance C versus voltage V) loops are determined for the characterization of ferroelectric material. The ε 33 coefficient is used for the ceramic characterization because it is strongly correlated with the ceramic quality. The purpose of this paper is to develop a model of reversal polarization behaviour close to physical realities, able to provide good performances on the simulation of dielectric permittivity loop ε 33 (E dc ). Simulated behaviours are finally compared with experimental results on a typically soft PZT ferroelectric ceramic

  4. Influence of the local structure in phase-change materials on their dielectric permittivity.

    Science.gov (United States)

    Shportko, Kostiantyn V; Venger, Eugen F

    2015-01-01

    Ge-Sb-Te alloys, which belong to the phase-change materials, are promising materials for data storage and display and data visualization applications due to their unique properties. This includes a remarkable difference of their electrical and optical properties in the amorphous and crystalline state. Pronounced change of optical properties for Ge-Sb-Te alloys is linked to the different bonding types and different atomic arrangements in amorphous and crystalline states. The dielectric function of phase-change materials has been investigated in the far infrared (FIR) range. Phonons have been detected by FTIR spectroscopy. Difference of the dispersion of the dielectric permittivity of amorphous and crystalline samples is caused by different structures in different states which contribute to the dielectric permittivity.

  5. Relation between task complexity and variability of procedure progression during an emergency operation

    International Nuclear Information System (INIS)

    Kim, Yochan; Park, Jinkyun; Jung, Wondea

    2013-01-01

    Highlights: • The relation between task complexity and the variability of procedure progression was investigated. • The two quantitative measures, TACOM and VPP, were applied to this study. • The task complexity was positively related with the operator’s procedural variability. • The VPP measure can be useful for explaining the operator’s behaviors. - Abstract: In this study, the relation between task complexity and variability of procedure progression during an emergency operation was investigated by comparing the two quantitative measures. To this end, the TACOM measure and VPP measure were applied to evaluate the complexity of tasks and variability of procedure progression, respectively. The TACOM scores and VPP scores were obtained for 60 tasks in the OPERA database, and a correlation analysis between two measures and a multiple regression analysis between the sub-measures of the TACOM measure and VPP measure were conducted. The results showed that the TACOM measure is positively associated with the VPP measure, and the abstraction hierarchy complexity mainly affected the variability among the sub-measures of TACOM. From these findings, it was discussed that the task complexity is related to an operator’s procedural variability and VPP measure can be useful for explaining the operator’s behaviors

  6. Development of a new prototype system for measuring the permittivity of dielectric materials

    Directory of Open Access Journals (Sweden)

    Jiajia Jiang

    2014-06-01

    Full Text Available A simple prototype for measuring the properties of dielectric materials is introduced in this Letter. A homogeneous dielectric sample placed in a field produced by a nearby antenna will affect the input impedance of the antenna. The permittivity and the loss of the dielectric sample can then be determined from the change of the input impedance of the antenna. The prototype has been validated by experiments.

  7. Enhancement of dielectric permittivity by incorporating PDMS-PEG multiblock copolymers in silicone elastomers

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Szabo, Peter; Skov, Anne Ladegaard

    2015-01-01

    A silicone elastomer from PDMS-PEG multiblock copolymer has been prepared by use of silylation reactions for both copolymer preparation and crosslinking. The dielectric and mechanical properties of the silicone elastomers were carefully investigated, as well as the morphology of the elastomers wa...... to a significantly increased dielectric permittivity. The conductivity also remained low due to the resulting discontinuity in PEG within the silicone matrix....

  8. Experimental Investigation of Electrical Conductivity and Permittivity of SC-TiO 2 -EG Nanofluids

    Science.gov (United States)

    Fal, Jacek; Barylyak, Adriana; Besaha, Khrystyna; Bobitski, Yaroslav V.; Cholewa, Marian; Zawlik, Izabela; Szmuc, Kamil; Cebulski, Józef; żyła, Gaweł

    2016-08-01

    The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration were investigated. Based on the curves of ac conductivity, dc conductivity was calculated, and 400 % enhancement in dc conductivity was exposed.

  9. Light harvesting complexes of Chromera velia, photosynthetic relative of apicomplexan parasites

    KAUST Repository

    Tichý, Josef

    2013-06-01

    The structure and composition of the light harvesting complexes from the unicellular alga Chromera velia were studied by means of optical spectroscopy, biochemical and electron microscopy methods. Two different types of antennae systems were identified. One exhibited a molecular weight (18-19 kDa) similar to FCP (fucoxanthin chlorophyll protein) complexes from diatoms, however, single particle analysis and circular dichroism spectroscopy indicated similarity of this structure to the recently characterized XLH antenna of xanthophytes. In light of these data we denote this antenna complex CLH, for "Chromera Light Harvesting" complex. The other system was identified as the photosystem I with bound Light Harvesting Complexes (PSI-LHCr) related to the red algae LHCI antennae. The result of this study is the finding that C. velia, when grown in natural light conditions, possesses light harvesting antennae typically found in two different, evolutionary distant, groups of photosynthetic organisms. © 2013 Elsevier B.V. All rights reserved.

  10. Effect of Substrate Permittivity and Thickness on Performance of Single-Layer, Wideband, U-Slot Antennas on Microwave Substrates

    National Research Council Canada - National Science Library

    Natarajan, V; Chatterjee, D

    2004-01-01

    This paper presents effects of substrate permittivity and thickness on the performance characteristics like impedance bandwidth, radiation efficiency and gain of a single-layer, wideband, U-slot antenna...

  11. Complexity Triggered by Economic Globalisation— The Issue of On-Line Betting-Related Match Fixing

    Directory of Open Access Journals (Sweden)

    Wladimir Andreff

    2017-02-01

    Full Text Available Complexity in mainstream economics consists in high intermediary consumption of mathematics. A new approach to complexity economics dwells upon path-dependent global systems; their emergence and evolving organisation. The focus here is on the complexity of the real economic world due to globalisation. On-line betting related match-fixing is a case in point about which the article presents non-exhaustive empirical evidence and shows how it is analysed with the standard model of the economics of crime. There is no room for complexity in such an individualistic approach to corrupt behaviour applied to bet-related fixes. A more complex model is sketched based on interactions between a global (though underground market for fixes and the actual partly legal, partly illegal global sport betting market. These interactions exhibit how complex is the issue of combating betting-related match fixing. Reviewing those major policies envisaged for containing the latter—prohibition; sanctions; regulation; privatisation (betting rights—the article opts for a global ‘Sportbettobin’ tax on sport betting gains; in the same vein as the famous Tobin tax on international capital transfers. The novelty in this approach is a variable (increasing rate applied to increasing tranches of taxation (gains which should dry up the worst cases of on-line bettingrelated match fixing.

  12. Typological diversity of tall buildings and complexes in relation to their functional structure

    Science.gov (United States)

    Generalov, Viktor P.; Generalova, Elena M.; Kalinkina, Nadezhda A.; Zhdanova, Irina V.

    2018-03-01

    The paper focuses on peculiarities of tall buildings and complexes, their typology and its formation in relation to their functional structure. The research is based on the analysis of tall buildings and complexes and identifies the following main functional elements of their formation: residential, administrative (office), hotel elements. The paper also considers the following services as «disseminated» in the space-planning structure: shops, medicine, entertainment, kids and sports facilities, etc., their location in the structure of the total bulk of the building and their impact on typological diversity. Research results include suggestions to add such concepts as «single-function tall buildings» and «mixed-use tall buildings and complexes» into the classification of tall buildings. In addition, if a single-function building or complex performs serving functions, it is proposed to add such concepts as «a residential tall building (complex) with provision of services», «an administrative (public) tall building (complex) with provision of services» into the classification of tall buildings. For mixed-use buildings and complexes the following terms are suggested: «a mixed-use tall building with provision of services», «a mixed-use tall complex with provision of services».

  13. Characterization of the permittivity of controlled porous water ice-dust mixtures to support the radar exploration of icy bodies

    OpenAIRE

    Brouet, Y.; Neves, L.; Sabouroux, P.; Levasseur-Regourd, A. C.; Poch, O.; Encrenaz, P.; Pommerol, Antoine; Thomas, N.; Kofman, W.

    2016-01-01

    The internal properties of porous and icy bodies in the solar system can be investigated by ground-penetrating radars (GPRs), like the COmet Nucleus Sounding Experiment by Radiowave Transmission instrument on board the Rosetta spacecraft which has sounded the interior of the nucleus of comet 67P/Churyumov-Gerasimenko. Accurate constraints on the permittivity of icy media are needed for the interpretation of the data. We report novel permittivity measurements performed on water ice samples and...

  14. A Variational Approach to the Estimate of the Permittivity of a Composite with Dispersed Inclusions

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2015-01-01

    Full Text Available Composites are inhomogeneous materials (heterogeneous solid body, which fall into the matrix and inclusions. The matrix in a composite is a binder between the inclusions. The properties of the inclusions mainly determine the application of composites. Selection of the characteristics of the matrix and inclusions enables us to meet the requirements for materials to be used in various fields of technology. Composites are widely used as structural or thermal protection material and as functional materials in various electrical devices, including dielectrics. One of the most important characteristics of the composite dielectric is the relative permittivity. The latter is primarily determined by the dielectric properties of the matrix and inclusions, as well as the shape and volume concentration of inclusions.For a composite with dispersed inclusions we are able to construct adequate mathematical models which enable us to predict sufficiently reliably the dependence of its dielectric constant on these defining parameters. In this paper, among the various approaches to the construction of such models we emphasize a variational approach which allows us not only to determine this dependence, but also obtain guaranteed bilateral boundaries of the area of possible values of the dielectric constant of the composite used to estimate the highest accuracy of calculated values.The representative element of the composite structure with inclusions of spherical shape modeling the form of dispersed inclusions with dimensions close to all directions is considered. For the representative element we obtained the electrostatic potential distribution that is permissible for the minimized functional. The latter is the part of the variational form of a mathematical model which describes the dielectric properties of the considered composite. From the equality of the values of this functional on the received permissible distribution in a representative element of the

  15. NHL and RCGA Based Multi-Relational Fuzzy Cognitive Map Modeling for Complex Systems

    Directory of Open Access Journals (Sweden)

    Zhen Peng

    2015-11-01

    Full Text Available In order to model multi-dimensions and multi-granularities oriented complex systems, this paper firstly proposes a kind of multi-relational Fuzzy Cognitive Map (FCM to simulate the multi-relational system and its auto construct algorithm integrating Nonlinear Hebbian Learning (NHL and Real Code Genetic Algorithm (RCGA. The multi-relational FCM fits to model the complex system with multi-dimensions and multi-granularities. The auto construct algorithm can learn the multi-relational FCM from multi-relational data resources to eliminate human intervention. The Multi-Relational Data Mining (MRDM algorithm integrates multi-instance oriented NHL and RCGA of FCM. NHL is extended to mine the causal relationships between coarse-granularity concept and its fined-granularity concepts driven by multi-instances in the multi-relational system. RCGA is used to establish high-quality high-level FCM driven by data. The multi-relational FCM and the integrating algorithm have been applied in complex system of Mutagenesis. The experiment demonstrates not only that they get better classification accuracy, but it also shows the causal relationships among the concepts of the system.

  16. On El Naschie's complex time, Hawking's imaginary time and special relativity

    International Nuclear Information System (INIS)

    Mejias, Antonio; Di Sigalotti, Leonardo G.; Sira, Eloy; De Felice, Fernando

    2004-01-01

    The idea of complex time, as first proposed by El Naschie in 1995, not only provided a very important mathematical utility in clarifying the nature of nowness, but also opened a definite possibility for the instantaneous transmission of information through the theoretical prediction of massless particles travelling at velocities larger than the speed of light. Based on a very simple thought experiment, here we show that the complex nature of time arises when two independent inertial observers, in relative uniform motion, communicate via a light signal in order to compare their own proper time measurements for the same event. The observation that the time employed by the signal to go from one observer to the other is calculable, but not measurable, permits to build up a general expression for the complex time, which not only complies with the possibility of time decomposition into two dimensions, but also conciliates with the idea of a complex space. In particular, we find that El Naschie's complex time can be interpreted as an asymptotic limit when the velocity of the moving observer equals that of light. Within this new formulation, the inverse Lorentz transformations of special relativity follow as a direct consequence of the complex time

  17. Self-complexity as a cognitive buffer against stress-related illness and depression.

    Science.gov (United States)

    Linville, P W

    1987-04-01

    This prospective study tested the self-complexity buffering hypothesis that greater self-complexity moderates the adverse impact of stress on depression and illness. This hypothesis follows from a model that assumes self-knowledge is represented in terms of multiple self-aspects. As defined in this model, greater self-complexity involves representing the self in terms of a greater number of cognitive self-aspects and maintaining greater distinctions among self-aspects. Subjects completed measures of stressful events, self-complexity, depression, and illness in two sessions separated by 2 weeks. A multiple regression analysis used depression and illness at Time 2 as outcomes, stressful life events and self-complexity at Time 1 as predictors, and depression and illness at Time 1 as control variables. The Stress X Self-Complexity interaction provided strong support for the buffering hypothesis. Subjects higher in self-complexity were less prone to depression, perceived stress, physical symptoms, and occurrence of the flu and other illnesses following high levels of stressful events. These results suggest that vulnerability to stress-related depression and illness is due, in part, to differences in cognitive representations of the self.

  18. The Complex Neutrosophic Soft Expert Relation and Its Multiple Attribute Decision-Making Method

    Directory of Open Access Journals (Sweden)

    Ashraf Al-Quran

    2018-01-01

    Full Text Available This paper introduces a novel soft computing technique, called the complex neutrosophic soft expert relation (CNSER, to evaluate the degree of interaction between two hybrid models called complex neutrosophic soft expert sets (CNSESs. CNSESs are used to represent two-dimensional data that are imprecise, uncertain, incomplete and indeterminate. Moreover, it has a mechanism to incorporate the parameter set and the opinions of all experts in one model, thus making it highly suitable for use in decision-making problems where the time factor plays a key role in determining the final decision. The complex neutrosophic soft expert set and complex neutrosophic soft expert relation are both defined. Utilizing the properties of CNSER introduced, an empirical study is conducted on the relationship between the variability of the currency exchange rate and Malaysian exports and the time frame (phase of the interaction between these two variables. This study is supported further by an algorithm to determine the type and the degree of this relationship. A comparison between different existing relations and CNSER to show the ascendancy of our proposed CNSER is provided. Then, the notion of the inverse, complement and composition of CNSERs along with some related theorems and properties are introduced. Finally, we define the symmetry, transitivity and reflexivity of CNSERs, as well as the equivalence relation and equivalence classes on CNSESs. Some interesting properties are also obtained.

  19. Measurement of the permittivity and loss of high-loss materials using a Near-Field Scanning Microwave Microscope

    International Nuclear Information System (INIS)

    Gregory, A.P.; Blackburn, J.F.; Lees, K.; Clarke, R.N.; Hodgetts, T.E.; Hanham, S.M.; Klein, N.

    2016-01-01

    In this paper improvements to a Near-Field Scanning Microwave Microscope (NSMM) are presented that allow the loss of high loss dielectric materials to be measured accurately at microwave frequencies. This is demonstrated by measuring polar liquids (loss tangent tanδ≈1) for which traceable data is available. The instrument described uses a wire probe that is electromagnetically coupled to a resonant cavity. An optical beam deflection system is incorporated within the instrument to allow contact mode between samples and the probe tip to be obtained. Liquids are contained in a measurement cell with a window of ultrathin glass. The calibration process for the microscope, which is based on image-charge electrostatic models, has been adapted to use the Laplacian ‘complex frequency’. Measurements of the loss tangent of polar liquids that are consistent with reference data were obtained following calibration against single-crystal specimens that have very low loss. - Highlights: • Design of a microwave microscope with resolution on the micron scale. • Improved theory for obtaining permittivity and loss tangent of high loss materials. • Polar reference liquids are used as test samples. • Traceable measurements with accuracy approximately ±10% in ε′ and ±20% in tan δ.

  20. Critical dynamics and domain motion from permittivity of the electronic ferroelectric (TMTTF){sub 2}AsF{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Brazovskii, Serguei, E-mail: brazov@lptms.u-psud.fr [LPTMS, UMR8626, CNRS & University Paris-Sud, Bat. 100, Orsay F-91405 (France); International Institute of Physics, 59078-400 Natal, Rio Grande do Norte (Brazil); Monceau, Pierre [CNRS & University Grenoble Alpes, Institute NEEL, F-38042 Grenoble (France); Nad, Felix Ya.

    2015-03-01

    The quasi one-dimensional organic conductor (TMTTF){sub 2}AsF{sub 6} shows the charge ordering transition at T{sub CO}=101 K to a state of the ferroelectric Mott insulator which is still well conducting. We present and interpret the experimental data on the gigantic dielectric response in the vicinity of T{sub CO}, concentrating on the frequency dependence of the inverse 1/ε of the complex permittivity ε=ε′+iε′′. Surprisingly for a ferroelectric, we could closely approach the 2nd order phase transition and to deeply reach the critical dynamics of the polarization. We could analyze the critical slowing-down when approaching T{sub CO} from both sides and to extract the anomalous power law for the frequency dependence of the order parameter viscosity. Moreover, below T{sub CO} we could extract a sharp absorption feature coming from a motion of domain walls which shows up at a frequency well below the relaxation rate.

  1. Intrathecal synthesis of antibodies to HTLV-III in patients without AIDS or AIDS related complex

    NARCIS (Netherlands)

    Goudsmit, J.; Wolters, E. C.; Bakker, M.; Smit, L.; van der Noordaa, J.; Hische, E. A.; Tutuarima, J. A.; van der Helm, H. J.

    1986-01-01

    De novo synthesis in the central nervous system of IgG antibodies to human T cell lymphotropic virus type III (HTLV-III) (lymphadenopathy associated virus) was shown in seven of 10 seropositive men who had syphilis but not the acquired immune deficiency syndrome (AIDS) or AIDS related complex. None

  2. A spatial compression technique for head-related transfer function interpolation and complexity estimation

    DEFF Research Database (Denmark)

    Shekarchi, Sayedali; Christensen-Dalsgaard, Jakob; Hallam, John

    2015-01-01

    A head-related transfer function (HRTF) model employing Legendre polynomials (LPs) is evaluated as an HRTF spatial complexity indicator and interpolation technique in the azimuth plane. LPs are a set of orthogonal functions derived on the sphere which can be used to compress an HRTF dataset...

  3. Reduced anterior cingulate and orbitofrontal volumes in child abuse-related complex PTSD

    NARCIS (Netherlands)

    Thomaes, K.; Dorrepaal, E.; Draijer, P.J.; de Ruiter, M.B.; van Balkom, A.J.L.M.; Smit, J.H.; Veltman, D.J.

    2010-01-01

    Objective: Classic posttraumatic stress disorder (PTSD) is associated with smaller hippocampus, amygdala, and anterior cingulate cortex (ACC) volumes. We investigated whether child abuse-related complex PTSD - a severe form of PTSD with affect dysregulation and high comorbidity-showed similar brain

  4. Reduced Anterior Cingulate and Orbitofrontal Volumes in Child Abuse-Related Complex PTSD

    NARCIS (Netherlands)

    Thomaes, Kathleen; Dorrepaal, Ethy; Draijer, Nel; de Ruiter, Michiel B.; van Balkom, Anton J.; Smit, Johannes H.; Veltman, Dick J.

    2010-01-01

    Objective: Classic posttraumatic stress disorder (PTSD) is associated with smaller hippocampus, amygdala, and anterior cingulate cortex (ACC) volumes. We investigated whether child abuse-related complex PTSD a severe form of PTSD with affect dysregulation and high comorbidity-showed similar brain

  5. Commentary on the Inclusion of Persistent Complex Bereavement-Related Disorder in DSM-5

    Science.gov (United States)

    Boelen, Paul A.; Prigerson, Holly G.

    2012-01-01

    The DSM-5 Anxiety, Obsessive-Compulsive Spectrum, Posttraumatic, and Dissociative Disorders Work Group has proposed criteria for Persistent Complex Bereavement-Related Disorder (PCBRD) for inclusion in the appendix of DSM-5. The authors feel that it is important that dysfunctional grief will become a formal condition in DSM-5 because that would…

  6. A complex linear least-squares method to derive relative and absolute orientations of seismic sensors

    OpenAIRE

    F. Grigoli; Simone Cesca; Torsten Dahm; L. Krieger

    2012-01-01

    Determining the relative orientation of the horizontal components of seismic sensors is a common problem that limits data analysis and interpretation for several acquisition setups, including linear arrays of geophones deployed in borehole installations or ocean bottom seismometers deployed at the seafloor. To solve this problem we propose a new inversion method based on a complex linear algebra approach. Relative orientation angles are retrieved by minimizing, in a least-squares sense, the l...

  7. The complex and quaternionic quantum bit from relativity of simultaneity on an interferometer.

    Science.gov (United States)

    Garner, Andrew J P; Müller, Markus P; Dahlsten, Oscar C O

    2017-12-01

    The patterns of fringes produced by an interferometer have long been important testbeds for our best contemporary theories of physics. Historically, interference has been used to contrast quantum mechanics with classical physics, but recently experiments have been performed that test quantum theory against even more exotic alternatives. A physically motivated family of theories are those where the state space of a two-level system is given by a sphere of arbitrary dimension. This includes classical bits, and real, complex and quaternionic quantum theory. In this paper, we consider relativity of simultaneity (i.e. that observers may disagree about the order of events at different locations) as applied to a two-armed interferometer, and show that this forbids most interference phenomena more complicated than those of complex quantum theory. If interference must depend on some relational property of the setting (such as path difference), then relativity of simultaneity will limit state spaces to standard complex quantum theory, or a subspace thereof. If this relational assumption is relaxed, we find one additional theory compatible with relativity of simultaneity: quaternionic quantum theory. Our results have consequences for current laboratory interference experiments: they have to be designed carefully to avoid rendering beyond-quantum effects invisible by relativity of simultaneity.

  8. Task Complexity Modulates Sleep-Related Offline Learning in Sequential Motor Skills

    Directory of Open Access Journals (Sweden)

    Klaus Blischke

    2017-07-01

    Full Text Available Recently, a number of authors have advocated the introduction of gross motor tasks into research on sleep-related motor offline learning. Such tasks are often designed to be more complex than traditional key-pressing tasks. However, until now, little effort has been undertaken to scrutinize the role of task complexity in any systematic way. Therefore, the effect of task complexity on the consolidation of gross motor sequence memory was examined by our group in a series of three experiments. Criterion tasks always required participants to produce unrestrained arm movement sequences by successively fitting a small peg into target holes on a pegboard. The sequences always followed a certain spatial pattern in the horizontal plane. The targets were visualized prior to each transport movement on a computer screen. The tasks differed with respect to sequence length and structural complexity. In each experiment, half of the participants initially learned the task in the morning and were retested 12 h later following a wake retention interval. The other half of the subjects underwent practice in the evening and was retested 12 h later following a night of sleep. The dependent variables were the error rate and total sequence execution time (inverse to the sequence execution speed. Performance generally improved during acquisition. The error rate was always low and remained stable during retention. The sequence execution time significantly decreased again following sleep but not after waking when the sequence length was long and structural complexity was high. However, sleep-related offline improvements were absent when the sequence length was short or when subjects performed a highly regular movement pattern. It is assumed that the occurrence of sleep-related offline performance improvements in sequential motor tasks is associated with a sufficient amount of motor task complexity.

  9. Noncovalent Complexation of Monoamine Neurotransmitters and Related Ammonium Ions by Tetramethoxy Tetraglucosylcalix[4]arene

    Science.gov (United States)

    Torvinen, Mika; Kalenius, Elina; Sansone, Francesco; Casnati, Alessandro; Jänis, Janne

    2012-02-01

    The noncovalent complexation of monoamine neurotransmitters and related ammonium and quaternary ammonium ions by a conformationally flexible tetramethoxy glucosylcalix[4]arene was studied by electrospray ionization Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry. The glucosylcalixarene exhibited highest binding affinity towards serotonin, norepinephrine, epinephrine, and dopamine. Structural properties of the guests, such as the number, location, and type of hydrogen bonding groups, length of the alkyl spacer between the ammonium head-group and the aromatic ring structure, and the degree of nitrogen substitution affected the complexation. Competition experiments and guest-exchange reactions indicated that the hydroxyl groups of guests participate in intermolecular hydrogen bonding with the glucocalixarene.

  10. Caring as emancipatory nursing praxis: the theory of relational caring complexity.

    Science.gov (United States)

    Ray, Marilyn A; Turkel, Marian C

    2014-01-01

    In the culture of health care, nurses are challenged to understand their values and beliefs as humanistic within complex technical and economically driven bureaucratic systems. This article outlines the language of social justice and human rights and the advance of a Theory of Relational Caring Complexity, which offers insights into caring as emancipatory nursing praxis. Recommendations provide knowledge of the struggle to balance economics, technology, and caring. As nurses practice from a value-driven, philosophical, and ethical social justice framework, they will find "their voice" and realize the full potential that the power of caring has on patient and organizational outcomes.

  11. Mediation, moderation, and context: Understanding complex relations among cognition, affect, and health behaviour.

    Science.gov (United States)

    Kiviniemi, Marc T; Ellis, Erin M; Hall, Marissa G; Moss, Jennifer L; Lillie, Sarah E; Brewer, Noel T; Klein, William M P

    2018-01-01

    Researchers have historically treated cognition and affect as separate constructs in motivating health behaviour. We present a framework and empirical evidence for complex relations between cognition and affect in predicting health behaviour. Main Outcome, Design and Results: First, affect and cognition can mediate each other's relation to health behaviour. Second, affect and cognition can moderate the other's impact. Third, context can change the interplay of affect and cognition. Fourth, affect and cognition may be indelibly fused in some psychological constructs (e.g. worry, anticipated regret and reactance). These four propositions in our framework are not mutually exclusive. Examination of the types of complex relations described here can benefit theory development, empirical testing of theories and intervention design. Doing so will advance the understanding of mechanisms involved in regulation of health behaviours and the effectiveness of interventions to change health behaviours.

  12. Permittivity, molar volume and crytical phenomena near the lambda-point in liquid 4He

    International Nuclear Information System (INIS)

    Panov, V.I.; Khvostikov, V.A.

    1982-01-01

    The permittivity, molar volume and thermal expansion coefficient at the saturated vapor pressure are measured for liquid helium 4 He in the temperature range from 1.4 to 4.2 K. It is shown that the thermal expansion coefficient at saturated vapor pressure near the lambda-transition can be described with a high degree of accuracy by a logarithmic function. The values of the critical indexes obtained by studying the nature of the divergence of the isobaric thermal expansion coefficient at 1x10sup(-5) Tsub(lambda) and α'=0.000+-0.0025 for T 4 He near the lambda transition

  13. Predictors of Health-Related Quality-of-Life After Complex Adult Spinal Deformity Surgery

    DEFF Research Database (Denmark)

    Carreon, Leah Y.; Glassman, Steven D.; Shaffrey, Christopher I.

    2017-01-01

    , treatment effectiveness is assessed by the extent to which the procedure improves a patient's health-related quality of life (HRQOL). This is especially true in patients with complex adult spinal deformity. Methods The data set from the Scoli-Risk-1 study was queried for patients with complete 2-year SF-36......Study Design Longitudinal cohort. Objectives To identify variables that predict 2-year Short Form-36 Physical Composite Summary Score (SF-36PCS) and the Scoliosis Research Society-22R (SRS22-R) Total score after surgery for complex adult spinal deformity. Summary of Background Data Increasingly...... = .049) and type of neurologic complication (p = .068). Factors predictive of 2-year SRS-22R Total scores were maximum preoperative Cobb angle (p = .001) and the number of serious adverse events (p = .071). Conclusions Factors predictive of lower 2-year HRQOLs after surgery for complex adult spinal...

  14. Hydrogen-related complexes in Li-diffused ZnO single crystals

    Science.gov (United States)

    Corolewski, Caleb D.; Parmar, Narendra S.; Lynn, Kelvin G.; McCluskey, Matthew D.

    2016-07-01

    Zinc oxide (ZnO) is a wide band gap semiconductor and a potential candidate for next generation white solid state lighting applications. In this work, hydrogen-related complexes in lithium diffused ZnO single crystals were studied. In addition to the well-known Li-OH complex, several other hydrogen defects were observed. When a mixture of Li2O and ZnO is used as the dopant source, zinc vacancies are suppressed and the bulk Li concentration is very high (>1019 cm-3). In that case, the predominant hydrogen complex has a vibrational frequency of 3677 cm-1, attributed to surface O-H species. When Li2CO3 is used, a structured blue luminescence band and O-H mode at 3327 cm-1 are observed at 10 K. These observations, along with positron annihilation measurements, suggest a zinc vacancy-hydrogen complex, with an acceptor level ˜0.3 eV above the valence-band maximum. This relatively shallow acceptor could be beneficial for p-type ZnO.

  15. Hydrogen-related complexes in Li-diffused ZnO single crystals

    International Nuclear Information System (INIS)

    Corolewski, Caleb D.; Parmar, Narendra S.; Lynn, Kelvin G.; McCluskey, Matthew D.

    2016-01-01

    Zinc oxide (ZnO) is a wide band gap semiconductor and a potential candidate for next generation white solid state lighting applications. In this work, hydrogen-related complexes in lithium diffused ZnO single crystals were studied. In addition to the well-known Li-OH complex, several other hydrogen defects were observed. When a mixture of Li_2O and ZnO is used as the dopant source, zinc vacancies are suppressed and the bulk Li concentration is very high (>10"1"9" cm"−"3). In that case, the predominant hydrogen complex has a vibrational frequency of 3677 cm"−"1, attributed to surface O-H species. When Li_2CO_3 is used, a structured blue luminescence band and O-H mode at 3327 cm"−"1 are observed at 10 K. These observations, along with positron annihilation measurements, suggest a zinc vacancy–hydrogen complex, with an acceptor level ∼0.3 eV above the valence-band maximum. This relatively shallow acceptor could be beneficial for p-type ZnO.

  16. Hydrogen-related complexes in Li-diffused ZnO single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Corolewski, Caleb D. [Materials Science and Engineering Program, Washington State University, Pullman, Washington 99164-2814 (United States); Parmar, Narendra S.; Lynn, Kelvin G. [Center for Materials Research, Washington State University, Pullman, Washington 99164-2814 (United States); McCluskey, Matthew D., E-mail: mattmcc@wsu.edu [Materials Science and Engineering Program, Washington State University, Pullman, Washington 99164-2814 (United States); Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)

    2016-07-21

    Zinc oxide (ZnO) is a wide band gap semiconductor and a potential candidate for next generation white solid state lighting applications. In this work, hydrogen-related complexes in lithium diffused ZnO single crystals were studied. In addition to the well-known Li-OH complex, several other hydrogen defects were observed. When a mixture of Li{sub 2}O and ZnO is used as the dopant source, zinc vacancies are suppressed and the bulk Li concentration is very high (>10{sup 19 }cm{sup −3}). In that case, the predominant hydrogen complex has a vibrational frequency of 3677 cm{sup −1}, attributed to surface O-H species. When Li{sub 2}CO{sub 3} is used, a structured blue luminescence band and O-H mode at 3327 cm{sup −1} are observed at 10 K. These observations, along with positron annihilation measurements, suggest a zinc vacancy–hydrogen complex, with an acceptor level ∼0.3 eV above the valence-band maximum. This relatively shallow acceptor could be beneficial for p-type ZnO.

  17. Implementation of Cavity Perturbation Method for Determining Relative Permittivity of Non Magnetic Materials

    Directory of Open Access Journals (Sweden)

    FAHIM GOHARAWAN

    2017-04-01

    Full Text Available Techniques for the cavity measurement of the electrical characteristics of the materials are well established using the approximate method due to its simplicity in material insertion and fabrication. However, the exact method which requires more comprehensive mathematical analysis as well, owing to the practical difficulties for the material insertion, is not mostly used while performing the measurements as compared to approximate method in most of the works. In this work the comparative analysis of both the approximate as well as Exact method is performed and accuracy of the Exact method is established by performing the measurements of non-magnetic material Teflon within the cavity.

  18. Implementation of cavity perturbation method for determining relative permittivity of non magnetic materials

    International Nuclear Information System (INIS)

    Awan, F.G.; Sheikh, N.A.; Qureshi, S.A.; Sheikh, N.M.

    2017-01-01

    Techniques for the cavity measurement of the electrical characteristics of the materials are well established using the approximate method due to its simplicity in material insertion and fabrication. However, the exact method which requires more comprehensive mathematical analysis as well, owing to the practical difficulties for the material insertion, is not mostly used while performing the measurements as compared to approximate method in most of the works. In this work the comparative analysis of both the approximate as well as Exact method is performed and accuracy of the Exact method is established by performing the measurements of non-magnetic material Teflon within the cavity. (author)

  19. Environmental Complexity Related Information for the Assessment of Country Logistics Environments

    DEFF Research Database (Denmark)

    Kinra, Aseem

    2015-01-01

    logistics assessment generates some of this information, its relevance for the decision makers, and relationship to their unpredictability from foreign national logistics systems remains indefinite. This paper identifies and categorises the relevant, available information on country logistics environments...... by using a content analysis approach. We demonstrate the immensity and nature of this information, are able to confirm the changing spatial transaction cost structures, and to reflect upon the overall conditions of information-related complexity and globalisation in the environment. Besides making...

  20. Mechanical properties of the normal human cartilage-bone complex in relation to age

    DEFF Research Database (Denmark)

    Ding, Ming; Dalstra, M; Linde, F

    1998-01-01

    OBJECTIVE: This study investigates the age-related variations in the mechanical properties of the normal human tibial cartilage-bone complex and the relationships between cartilage and bone. DESIGN: A novel technique was applied to assess the mechanical properties of the cartilage and bone by mea...... that are of importance for the understanding of the etiology and pathogenesis of degenerative joint diseases, such as arthrosis....

  1. Thyroid hormone levels in the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex.

    OpenAIRE

    Tang, W W; Kaptein, E M

    1989-01-01

    Hypothalamic-pituitary dysfunction and thyroid gland cytomegalovirus inclusions have been described in patients with the acquired immunodeficiency syndrome (AIDS) and AIDS-related complex (ARC). We evaluated 80 patients with AIDS or ARC for the frequency of hypothalamic-pituitary or thyroid gland failure and altered serum thyroid hormone levels due to nonthyroidal disorders. One patient had subclinical hypothyroidism. Of these patients, 60% had low free triiodothyronine (T3) index values and ...

  2. Use of probabilistic relational model (PRM) for dependability analysis of complex systems

    OpenAIRE

    Medina-Oliva , Gabriela; Weber , Philippe; Levrat , Eric; Iung , Benoît

    2010-01-01

    International audience; This paper proposes a methodology to develop a aided decision-making tool for assessing the dependability and performances (i.e. reliability) of an industrial system. This tool is built on a model based on a new formalism, called the probabilistic relational model (PRM) which is adapted to deal with large and complex systems. The model is formalized from functional, dysfunctional and informational studies of the technical industrial systems. An application of this meth...

  3. Risk of AIDS related complex and AIDS in homosexual men with persistent HIV antigenaemia.

    OpenAIRE

    de Wolf, F; Goudsmit, J; Paul, D A; Lange, J M; Hooijkaas, C; Schellekens, P; Coutinho, R A; van der Noordaa, J

    1987-01-01

    One hundred and ninety eight men seropositive for human immunodeficiency virus (HIV) antibody and 58 HIV antibody seroconverters were studied for an average of 19.3 (SEM 0.5) months to assess the relation between HIV antigenaemia and the risk of developing the acquired immune deficiency syndrome (AIDS) and AIDS related complex. Forty (20.2%) of the 198 HIV antibody seropositive men were antigen positive at entry and remained so during follow up. Eight (13.8%) of the 58 HIV antibody seroconver...

  4. Relation between risk of falling and postural sway complexity in diabetes.

    Science.gov (United States)

    Morrison, S; Colberg, S R; Parson, H K; Vinik, A I

    2012-04-01

    For older individuals with diabetes, any decline in balance control can be especially problematic since it is often a precursor to an increased risk of falling. This study was designed to evaluate differences in postural motion dynamics and falls risk for older individuals with type 2 diabetes (T2DM) classified as fallers/non-fallers and, to assess what impact exercise has on balance and falls risk. The results demonstrated that the risk of falling is greater for those older individuals with multiple risk factors including diabetes and a previous falls history. The postural motion features of the high-risk individuals (T2DM-fallers) were also different, being characterized by increased variability and complexity, increased AP-ML coupling, less overall COP motion and increased velocity. One suggestion is that these individuals evoked a stiffening strategy during the more challenging postural tasks. Following training, a decline in falls risk was observed for all groups, with this effect being most pronounced for the T2DM-fallers. Interestingly, the COP motion of this group became more similar to controls, exhibiting decreased complexity and variability, and decreased velocity. The reciprocal changes in COP complexity support the broader view that age/disease-related changes in physiological complexity are bi-directional. Overall, these results show that, even for older T2DM individuals at greater risk of falling, targeted interventions can positively enhance their postural dynamics. Further, the finding that the pattern of postural motion variability and complexity was altered highlights that a decline in physiological complexity may not always be negatively associated with aging and/or disease. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Comparison of GFL–GFRα complexes: further evidence relating GFL bend angle to RET signalling

    International Nuclear Information System (INIS)

    Parkash, Vimal; Goldman, Adrian

    2009-01-01

    The second crystal structure of the GDNF-GFRα1 complex provides further evidence that GFL signalling through RET is determined by the bend angle in the GFL. Glial cell line-derived neurotrophic factor (GDNF) activates the receptor tyrosine kinase RET by binding to the GDNF-family receptor α1 (GFRα1) and forming the GDNF 2 –GFRα1 2 –RET 2 heterohexamer complex. A previous crystal structure of the GDNF 2 –GFRα1 2 complex suggested that differences in signalling in GDNF-family ligand (GFL) complexes might arise from differences in the bend angle between the two monomers in the GFL homodimer. Here, a 2.35 Å resolution structure of the GDNF 2 –GFRα1 2 complex crystallized with new cell dimensions is reported. The structure was refined to a final R factor of 22.5% (R free = 28%). The structures of both biological tetrameric complexes in the asymmetric unit are very similar to 2v5e and different from the artemin–GFRα3 structure, even though there is a small change in the structure of the GDNF. By comparison of all known GDNF and artemin structures, it is concluded that GDNF is more bent and more flexible than artemin and that this may be related to RET signalling. Comparisons also suggest that the differences between artemin and GDNF arise from the increased curvature of the artemin ‘fingers’, which both increases the buried surface area in the monomer–monomer interface and changes the intermonomer bend angle. From sequence comparison, it is suggested that neuturin (the second GFL) adopts an artemin-like conformation, while persephin has a different conformation to the other three

  6. High permittivity materials for oxide gate stack in Ge-based metal oxide semiconductor capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Molle, Alessandro, E-mail: alessandro.molle@mdm.infm.i [Laboratorio Nazionale MDM, CNR-INFM, via C. Olivetti 2, 20041 Agrate Brianza, Milano (Italy); Baldovino, Silvia [Laboratorio Nazionale MDM, CNR-INFM, via C. Olivetti 2, 20041 Agrate Brianza, Milano (Italy); Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca, Milano (Italy); Spiga, Sabina [Laboratorio Nazionale MDM, CNR-INFM, via C. Olivetti 2, 20041 Agrate Brianza, Milano (Italy); Fanciulli, Marco [Laboratorio Nazionale MDM, CNR-INFM, via C. Olivetti 2, 20041 Agrate Brianza, Milano (Italy); Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca, Milano (Italy)

    2010-01-01

    In the effort to ultimately shrink the size of logic devices towards a post-Si era, the integration of Ge as alternative channel material for high-speed p-MOSFET devices and the concomitant coupling with high permittivity dielectrics (high-k) as gate oxides is currently a key-challenge in microelectronics. However, the Ge option still suffers from a number of unresolved drawbacks and open issues mainly related to the thermodynamic and electrical compatibility of Ge substrates with high-k gate stack. Strictly speaking, two main concerns can be emphasized. On one side is the dilemma on which chemical/physical passivation is more suitable to minimize the unavoidable presence of electrically active defects at the oxide/semiconductor interface. On the other side, overcoming the SiO{sub 2} gate stack opens the route to a number of potentially outperforming high-k oxides. Two deposition approaches were here separately adopted to investigate the high-k oxide growth on Ge substrates, the molecular beam deposition (MBD) of Gd{sub 2}O{sub 3} and the atomic layer deposition (ALD) of HfO{sub 2}. In the MBD framework epitaxial and amorphous Gd{sub 2}O{sub 3} films were grown onto GeO{sub 2}-passivated Ge substrates. In this case, Ge passivation was achieved by exploiting the Ge{sup 4+} bonding state in GeO{sub 2} ultra-thin interface layers intentionally deposited in between Ge and the high-k oxide by means of atomic oxygen exposure to Ge. The composition of the interface layer has been characterized as a function of the oxidation temperature and evidence of Ge dangling bonds at the GeO{sub 2}/Ge interface has been reported. Finally, the electrical response of MOS capacitors incorporating Gd{sub 2}O{sub 3} and GeO{sub 2}-passivated Ge substrates has been checked by capacitance-voltage measurements. On the other hand, the structural and electrical properties of HfO{sub 2} films grown by ALD on Ge by using different oxygen precursors, i.e. H{sub 2}O, Hf(O{sup t}Bu){sub 2}(mmp

  7. Permittivity and performance of dielectric pads with sintered ceramic beads in MRI: early experiments and simulations at 3 T.

    Science.gov (United States)

    Luo, Wei; Lanagan, Michael T; Sica, Christopher T; Ryu, Yeunchul; Oh, Sukhoon; Ketterman, Matthew; Yang, Qing X; Collins, Christopher M

    2013-07-01

    Passive dielectric materials have been used to improve aspects of MRI by affecting the distribution of radiofrequency electromagnetic fields. Recently, interest in such materials has increased with the number of high-field MRI sites. Here, we introduce a new material composed of sintered high-permittivity ceramic beads in deuterated water. This arrangement maintains the ability to create flexible pads for conforming to individual subjects. The properties of the material are measured and the performance of the material is compared to previously used materials in both simulation and experiment at 3 T. Results show that both permittivity of the beads and effect on signal-to-noise ratio and required transmit power in MRI are greater than those of materials consisting of ceramic powder in water. Importantly, use of beads results in both higher permittivity and lower conductivity than use of powder. Copyright © 2012 Wiley Periodicals, Inc.

  8. Dielectric discontinuity at interfaces in the atomic-scale limit: permittivity of ultrathin oxide films on silicon.

    Science.gov (United States)

    Giustino, Feliciano; Umari, Paolo; Pasquarello, Alfredo

    2003-12-31

    Using a density-functional approach, we study the dielectric permittivity across interfaces at the atomic scale. Focusing on the static and high-frequency permittivities of SiO2 films on silicon, for oxide thicknesses from 12 A down to the atomic scale, we find a departure from bulk values in accord with experiment. A classical three-layer model accounts for the calculated permittivities and is supported by the microscopic polarization profile across the interface. The local screening varies on length scales corresponding to first-neighbor distances, indicating that the dielectric transition is governed by the chemical grading. Silicon-induced gap states are shown to play a minor role.

  9. Classification of Error Related Brain Activity in an Auditory Identification Task with Conditions of Varying Complexity

    Science.gov (United States)

    Kakkos, I.; Gkiatis, K.; Bromis, K.; Asvestas, P. A.; Karanasiou, I. S.; Ventouras, E. M.; Matsopoulos, G. K.

    2017-11-01

    The detection of an error is the cognitive evaluation of an action outcome that is considered undesired or mismatches an expected response. Brain activity during monitoring of correct and incorrect responses elicits Event Related Potentials (ERPs) revealing complex cerebral responses to deviant sensory stimuli. Development of accurate error detection systems is of great importance both concerning practical applications and in investigating the complex neural mechanisms of decision making. In this study, data are used from an audio identification experiment that was implemented with two levels of complexity in order to investigate neurophysiological error processing mechanisms in actors and observers. To examine and analyse the variations of the processing of erroneous sensory information for each level of complexity we employ Support Vector Machines (SVM) classifiers with various learning methods and kernels using characteristic ERP time-windowed features. For dimensionality reduction and to remove redundant features we implement a feature selection framework based on Sequential Forward Selection (SFS). The proposed method provided high accuracy in identifying correct and incorrect responses both for actors and for observers with mean accuracy of 93% and 91% respectively. Additionally, computational time was reduced and the effects of the nesting problem usually occurring in SFS of large feature sets were alleviated.

  10. Complexity Index as Applied to Magnetic Resonance: Study Based on a Scale of Relative Units

    International Nuclear Information System (INIS)

    Capelastegui, A.; Villanua, J.

    2003-01-01

    To analyze the merit and repercussions of measuring magnetic resonance (MR) activity in units of radiological activity, and of using complexity index (CI) as an activity indicator. We studied the MR activity of Osatek, Inc. during an 8-year period (1994-2001). We measured this activity both in number of MR procedures performed and in units of radiological activity, such units being based on the scale of relative units published in the Radiological Services Administration Guidelines published by the Spanish Society or Medical Radiology. We calculated the annual complexity index, this being a quotient between the number of MR procedures performed and corresponding value in units of radiological activity. We also analyzed factors that can have an impact on the CI: type of exploration and power of the equipment's magnetic field. The CL stayed practically stable during the first 4 years of the study, while it increased during the second 4 years. There exists a direct relationship between this increase and the percentage of explorations that we term complex (basically, body-and angio-MR). The increasing complexity of MR studies in the last years is evident from a consideration of CI. MR productivity is more realistically expressed in units of radiological activity than in number of procedures performed by any one center. It also allows for making external comparisons. CI is a useful indicator that can be utilized as an administrative tool. (Author) 13 refs

  11. Relation Between the Molopo Farms and Bushveld Complexes: An Analysis of Pyroxene Exsolution Lamellae

    Science.gov (United States)

    Moore, I.; Feineman, M. D.; Nyblade, A.

    2017-12-01

    The Molopo Farms Complex (MFC) is a layered igneous intrusion in Botswana, considered to be related to the nearby South African Bushveld Complex (BC) due to their similarities. The BC has been researched in depth for its economic deposits of platinum group elements (PGEs), while the under-researched MFC has no PGEs and is under 200 m of sediment. This study aims to increase knowledge about the MFC regarding the theory that the BC and MFC come from the same parental magma body by showing similar cooling history in the exsolution of pyroxenes. Using optical microscopy and scanning electron microscopy (SEM) paired with an energy-dispersive detector (EDS), thin sections of pyroxenes with exsolution lamellae from both complexes were observed in terms of chemical composition and microtextures. MFC pyroxenes were then compared to literature data of BC pyroxenes. The pyroxenes are closely related, indicating that the MFC and the BC cooled at a similar rate and come from the same parental magma body. Further research can expand on these findings to prove that the MFC and BC are from the same magma.

  12. Molding of plasmonic resonances in metallic nanostructures: Dependence of the non-linear electric permittivity on system size and temperature

    KAUST Repository

    Alabastri, A.; Tuccio, S.; Giugni, A.; Toma, A.; Liberale, Carlo; Das, G.; Angelis, F.D.; Fabrizio, E.D.; Zaccaria, R.P.

    2013-01-01

    In this paper, we review the principal theoretical models through which the dielectric function of metals can be described. Starting from the Drude assumptions for intraband transitions, we show how this model can be improved by including interband absorption and temperature effect in the damping coefficients. Electronic scattering processes are described and included in the dielectric function, showing their role in determining plasmon lifetime at resonance. Relationships among permittivity, electric conductivity and refractive index are examined. Finally, a temperature dependent permittivity model is presented and is employed to predict temperature and non-linear field intensity dependence on commonly used plasmonic geometries, such as nanospheres. 2013 by the authors; licensee MDPI, Basel, Switzerland.

  13. Large enhanced dielectric permittivity in polyaniline passivated core-shell nano magnetic iron oxide by plasma polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Joy, Lija K.; Sooraj, V.; Sethulakshmi, N.; Anantharaman, M. R., E-mail: mraiyer@yahoo.com [Department of Physics, Cochin University of Science and Technology, Cochin-682022, Kerala (India); Sajeev, U. S. [Department of Physics, Government College, Kottayam-686613, Kerala (India); Nair, Swapna S. [Department of Physics, School of Mathematical and Physical Sciences, Central University of Kerala, Kasargode-671123, Kerala (India); Narayanan, T. N. [CSIR-Central Electrochemical Research Institute, Karaikkudi-630006, Tamil Nadu (India); Ajayan, P. M. [Department of Material Science and Nano Engineering, Rice University, 6100 Main Street, Houston, Texas 7700 (United States)

    2014-03-24

    Commercial samples of Magnetite with size ranging from 25–30 nm were coated with polyaniline by using radio frequency plasma polymerization to achieve a core shell structure of magnetic nanoparticle (core)–Polyaniline (shell). High resolution transmission electron microscopy images confirm the core shell architecture of polyaniline coated iron oxide. The dielectric properties of the material were studied before and after plasma treatment. The polymer coated magnetite particles exhibited a large dielectric permittivity with respect to uncoated samples. The dielectric behavior was modeled using a Maxwell–Wagner capacitor model. A plausible mechanism for the enhancement of dielectric permittivity is proposed.

  14. Molding of plasmonic resonances in metallic nanostructures: Dependence of the non-linear electric permittivity on system size and temperature

    KAUST Repository

    Alabastri, A.

    2013-10-25

    In this paper, we review the principal theoretical models through which the dielectric function of metals can be described. Starting from the Drude assumptions for intraband transitions, we show how this model can be improved by including interband absorption and temperature effect in the damping coefficients. Electronic scattering processes are described and included in the dielectric function, showing their role in determining plasmon lifetime at resonance. Relationships among permittivity, electric conductivity and refractive index are examined. Finally, a temperature dependent permittivity model is presented and is employed to predict temperature and non-linear field intensity dependence on commonly used plasmonic geometries, such as nanospheres. 2013 by the authors; licensee MDPI, Basel, Switzerland.

  15. The Study of enclaves and relative age of plutonic bodies in the Alvand Plutonic complex

    International Nuclear Information System (INIS)

    Sepahi Gerow, A. A.; Moien-Vaziri, H.

    2000-01-01

    The study of enclaves and field observations indicate that: The Alvand plutonic complex comprise several plutonic phases with sharp contact and different ages. The older plutonic rocks are composed of gabbro, diorite and tonalites. The porphyroid granites were formed at least in two phases and they are younger than gabbros, diorites and tonalites. The hololeucocratic granitoids were also formed in two phases and they are the youngest plutonic phase in the Alvand plutonic complex. The granitic rocks are magmatic and they are not metasomatic in origin. The porphyroid granites (monzogranites and granodiorites) are S-type (Anatexites). According to radiometric ages and relative ages we believe that mafic plutonism have occurred during pre-middle Cretaceous to Paleocene ages and felsic plutonism have occurred during middle Cretaceouc to Paleocene ages

  16. Functional interplay between Mediator and TFIIB in preinitiation complex assembly in relation to promoter architecture.

    Science.gov (United States)

    Eychenne, Thomas; Novikova, Elizaveta; Barrault, Marie-Bénédicte; Alibert, Olivier; Boschiero, Claire; Peixeiro, Nuno; Cornu, David; Redeker, Virginie; Kuras, Laurent; Nicolas, Pierre; Werner, Michel; Soutourina, Julie

    2016-09-15

    Mediator is a large coregulator complex conserved from yeast to humans and involved in many human diseases, including cancers. Together with general transcription factors, it stimulates preinitiation complex (PIC) formation and activates RNA polymerase II (Pol II) transcription. In this study, we analyzed how Mediator acts in PIC assembly using in vivo, in vitro, and in silico approaches. We revealed an essential function of the Mediator middle module exerted through its Med10 subunit, implicating a key interaction between Mediator and TFIIB. We showed that this Mediator-TFIIB link has a global role on PIC assembly genome-wide. Moreover, the amplitude of Mediator's effect on PIC formation is gene-dependent and is related to the promoter architecture in terms of TATA elements, nucleosome occupancy, and dynamics. This study thus provides mechanistic insights into the coordinated function of Mediator and TFIIB in PIC assembly in different chromatin contexts. © 2016 Eychenne et al.; Published by Cold Spring Harbor Laboratory Press.

  17. New MR imaging observation in HIV-related cognitive impairment (AIDS dementia complex)

    International Nuclear Information System (INIS)

    Ketonen, L.; Kieburtz, K.D.; Zetteimaier, A.; Simon, J.H.; Kido, D.K.

    1989-01-01

    MR findings have been reported on the acquired immunodeficiency syndrome (AIDS) demential complex, but the findings are late relative to clinical signs. This paper reports on a new MR finding observed in patients with human immunodeficiency virus (HIV)-related cognitive impairment studied early in the disease process. Fifty-two patients had a total of 86 MR images. Al images were obtained with a 1.5-T system (protondensity, spin-echo, TR/TE = 2,000/30 [repetition time/echo time, msec]). High-signal lesions were seen in the region of the splenium of the corpus callosum and in the crura of the fornices. The lesions demonstrated no contrast enhancement with Gd-DTPA. Pathologic examination was performed in four patients. The fornix-subcallosal abnormality may have relevance to the memory dysfunction in patients with HIV-related cognitive impairment

  18. The relation between geometry and function of the ankle joint complex: a biomechanical review.

    Science.gov (United States)

    Kleipool, Roeland P; Blankevoort, Leendert

    2010-05-01

    This review deals with the relation between the anatomy and function of the ankle joint complex. The questions addressed are how high do the forces in the ankle joint get, where can the joints go (range of motion) and where do they go during walking and running. Finally the role of the ligaments and the articular surfaces is discussed, i.e. how does it happen. The magnitude of the loads on the ankle joint complex are primarily determined by muscle activity and can be as high as four times the body weight during walking. For the maximal range of motion, plantar and dorsiflexion occurs in the talocrural joint and marginally at the subtalar joint. In-eversion takes place at both levels. The functional range of motion is well within the limits of the maximal range of motion. The ligaments do not contribute to the forces for the functional range of motion but determine the maximal range of motion together with the articular surfaces. The geometry of the articular surfaces primarily determines the kinematics. Clinical studies must include these anatomical aspects to better understand the mechanism of injury, recovery, and interventions. Models can elucidate the mechanism by which the anatomy relates to the function. The relation between the anatomy and mechanical properties of the joint structures and joint function should be considered for diagnosis and treatment of ankle joint pathology.

  19. Radiation accelerated formation of oxygen and carbon related complexes in silicon

    International Nuclear Information System (INIS)

    Lazrak, A.; Magnea, N.; Pautrat, J.L.

    1984-06-01

    During the pulling of silicon monocrystals by the Czochralsky method, oxygen is incorporated into the lattice. It is known from early works that low temperature annealings (400-1000 0 C) make this oxygen to precipitate and a number of different defects to be generated. In order to check whether the fast diffusivity of an oxygen silicon interstitial complex has to be taken in consideration it was interesting to examinate the possible role of radiation damage on the formation of oxygen related defects. Experimental results of an experiment are presented and discussed

  20. Health-related fitness profiles in adolescents with complex congenital heart disease

    DEFF Research Database (Denmark)

    Klausen, Susanne Hwiid; Wetterslev, Jørn; Søndergaard, Lars

    2015-01-01

    PURPOSE: This study investigates whether subgroups of different health-related fitness (HrF) profiles exist among girls and boys with complex congenital heart disease (ConHD) and how these are associated with lifestyle behaviors. METHODS: We measured the cardiorespiratory fitness, muscle strength...... in the Robust clusters reported leading a physically active lifestyle and participants in the Less robust cluster reported leading a sedentary lifestyle. Diagnoses were evenly distributed between clusters. CONCLUSIONS: The cluster analysis attributed some of the variability in cardiorespiratory fitness among...

  1. Foreign currency-related translation complexities in cross-border healthcare applications.

    Science.gov (United States)

    Kumar, Anand; Rodrigues, Jean M

    2009-01-01

    International cross-border private hospital chains need to apply the standards for foreign currency translation in order to consolidate the balance sheet and income statements. This not only exposes such chains to exchange rate fluctuations in different ways, but also creates added requirements for enterprise-level IT systems especially when they produce parameters which are used to measure the financial and operational performance of the foreign subsidiary or the parent hospital. Such systems would need to come to terms with the complexities involved in such currency-related translations in order to provide the correct data for performance benchmarking.

  2. Space charge and steady state current in LDPE samples containing a permittivity/conductivity gradient

    DEFF Research Database (Denmark)

    Holbøll, Joachim; Bambery, K. R.; Fleming, R. J.

    2000-01-01

    Electromagnetic theory predicts that a dielectric sample in which a steady DC current of density ε is flowing, and in which the ratio of permittivity ε to conductivity σ varies with position, will acquire a space charge density j·grad(ε/σ). A simple and convenient way to generate an ε/σ gradient...... in a homogeneous sample is to establish a temperature gradient across it. The resulting spatial variation in ε is usually small in polymeric insulators, but the variation in σ can be appreciable. Laser induced pressure pulse (LIPP) measurements were made on 1.5 mm thick plaques of ultra pure LDPE equipped...... with vacuum-evaporated aluminium electrodes. Temperature differences up to 27°C were maintained across the samples, which were subjected to DC fields up to 20 kV/mm. Current density was measured as a function of temperature and field. Negligible thermally generated space charge was observed. The charge...

  3. Zero permeability and zero permittivity band gaps in 1D metamaterial photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Depine, Ricardo A. [Grupo de Electromagnetismo Aplicado, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, C1428EHA Buenos Aires (Argentina); Martinez-Ricci, Maria L. [Grupo de Electromagnetismo Aplicado, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, C1428EHA Buenos Aires (Argentina); Monsoriu, Juan A. [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, 46022 Valencia (Spain)]. E-mail: jmonsori@fis.upv.es; Silvestre, Enrique [Departamento de Optica, Universidad de Valencia, 46100 Burjassot (Spain); Andres, Pedro [Departamento de Optica, Universidad de Valencia, 46100 Burjassot (Spain)

    2007-04-30

    We consider layered heterostructures combining ordinary positive index materials and dispersive metamaterials. We show that these structures can exhibit a new type of photonic gap around frequencies where either the magnetic permeability {mu} or the electric permittivity {epsilon} of the metamaterial is zero. Although the interface of a semi-infinite medium with zero refractive index (a condition attained either when {mu}=0 or when {epsilon}=0) is known to give full reflectivity for all incident polarizations, here we show that a gap corresponding to {mu}=0 occurs only for TE polarized waves, whereas a gap corresponding to {epsilon}=0 occurs only for TM polarized waves. These band gaps are scale-length invariant and very robust against disorder, although they may disappear for the particular case of propagation along the stratification direction.

  4. Zero permeability and zero permittivity band gaps in 1D metamaterial photonic crystals

    International Nuclear Information System (INIS)

    Depine, Ricardo A.; Martinez-Ricci, Maria L.; Monsoriu, Juan A.; Silvestre, Enrique; Andres, Pedro

    2007-01-01

    We consider layered heterostructures combining ordinary positive index materials and dispersive metamaterials. We show that these structures can exhibit a new type of photonic gap around frequencies where either the magnetic permeability μ or the electric permittivity ε of the metamaterial is zero. Although the interface of a semi-infinite medium with zero refractive index (a condition attained either when μ=0 or when ε=0) is known to give full reflectivity for all incident polarizations, here we show that a gap corresponding to μ=0 occurs only for TE polarized waves, whereas a gap corresponding to ε=0 occurs only for TM polarized waves. These band gaps are scale-length invariant and very robust against disorder, although they may disappear for the particular case of propagation along the stratification direction

  5. Comparative study on electrical properties of atomic layer deposited high-permittivity materials on silicon substrates

    International Nuclear Information System (INIS)

    Duenas, S.; Castan, H.; Garcia, H.; Barbolla, J.; Kukli, K.; Ritala, M.; Leskelae, M.

    2005-01-01

    Deep level transient spectroscopy, capacitance-voltage and conductance transient measurement techniques have been applied in order to evaluate the electrical quality of thin high-permittivity oxide layers on silicon. The oxides studied included HfO 2 film grown from two different oxygen-free metal precursors and Ta 2 O 5 and Nb 2 O 5 nanolaminates. The interface trap densities correlated to the oxide growth chemistry and semiconductor substrate treatment. No gap state densities induced by structural disorder were measured in the films grown on chemical SiO 2 . Trap densities were also clearly lower in HfO 2 films compared to Ta 2 O 5 -Nb 2 O 5

  6. Philosophy, history and sociology of science: interdisciplinary relations and complex social identities.

    Science.gov (United States)

    Riesch, Hauke

    2014-12-01

    Sociology and philosophy of science have an uneasy relationship, while the marriage of history and philosophy of science has--on the surface at least--been more successful I will take a sociological look at the history of the relationships between philosophy and history as well as philosophy and sociology of science. Interdisciplinary relations between these disciplines will be analysed through social identity complexity theory in oider to draw out some conclusions on how the disciplines interact and how they might develop. I will use the relationships between the disciplines as a pointer for a more general social theory of interdisciplinarity which will then be used to sound a caution on how interdisciplinary relations between the three disciplines might be managed.

  7. Streamer discharge inception in a sub-breakdown electric field from a dielectric body with a frequency dependent dielectric permittivity

    NARCIS (Netherlands)

    A. A. Dubinova (Anna); C. Rutjes (Casper); U. M. Ebert (Ute)

    2015-01-01

    htmlabstractWe study positive streamer inception from the tip of an elongated ice particle. The dielectric permittivity of ice drops from 93 to 3 for electric fields changing on the millisecond timescale [1]. We demonstrate that this effect can be important on the nanosecond time scale of

  8. Negative permittivity of ZnO thin films prepared from aluminum and gallium doped ceramics via pulsed-laser deposition

    DEFF Research Database (Denmark)

    Bodea, M. A.; Sbarcea, G.; Naik, G. V.

    2013-01-01

    Aluminum and gallium doped zinc oxide thin films with negative dielectric permittivity in the near infrared spectral range are grown by pulsed laser deposition. Composite ceramics comprising ZnO and secondary phase Al2O3 or Ga2O3 are employed as targets for laser ablation. Films deposited on glass...

  9. Permittivity and Permeability for Floquet-Bloch Space Harmonics in Infinite 1D Magneto-Dielectric Periodic Structures

    DEFF Research Database (Denmark)

    Breinbjerg, Olav; Yaghjian, Arthur D.

    2014-01-01

    -Bloch space harmonics. We discuss how space harmonic permittivity and permeability can be expressed in seemingly different though equivalent forms, and we investigate these parameters of the zeroeth order space harmonic for a particular 1D periodic structure that is based on a previously reported 3D periodic...

  10. Human-Chromatin-Related Protein Interactions Identify a Demethylase Complex Required for Chromosome Segregation

    Directory of Open Access Journals (Sweden)

    Edyta Marcon

    2014-07-01

    Full Text Available Chromatin regulation is driven by multicomponent protein complexes, which form functional modules. Deciphering the components of these modules and their interactions is central to understanding the molecular pathways these proteins are regulating, their functions, and their relation to both normal development and disease. We describe the use of affinity purifications of tagged human proteins coupled with mass spectrometry to generate a protein-protein interaction map encompassing known and predicted chromatin-related proteins. On the basis of 1,394 successful purifications of 293 proteins, we report a high-confidence (85% precision network involving 11,464 protein-protein interactions among 1,738 different human proteins, grouped into 164 often overlapping protein complexes with a particular focus on the family of JmjC-containing lysine demethylases, their partners, and their roles in chromatin remodeling. We show that RCCD1 is a partner of histone H3K36 demethylase KDM8 and demonstrate that both are important for cell-cycle-regulated transcriptional repression in centromeric regions and accurate mitotic division.

  11. Syntactic Complexity Effects of Russian Relative Clause Sentences in Children with and without Developmental Language Disorder.

    Science.gov (United States)

    Rakhlin, Natalia; Kornilov, Sergey A; Kornilova, Tatiana V; Grigorenko, Elena L

    2016-01-01

    We investigated relative clause (RC) comprehension in 44 Russian-speaking children with typical language (TD) and developmental language disorder (DLD); M age = 10.67, SD = 2.84, and 22 adults. Flexible word order and morphological case in Russian allowed us to isolate factors that are obscured in English, helping us to identify sources of syntactic complexity and evaluate their roles in RC comprehension by children with typical language and their peers with DLD. We administered a working memory and an RC comprehension (picture-choice) task, which contained subject- and object-gap center-embedded and right branching RCs. The TD group, but not adults, demonstrated the effects of gap, embedding, and case. Their lower accuracy relative to adults was not fully attributable to differences in working memory. The DLD group displayed lower than TD children overall accuracy, accounted for by their lower working memory scores. While the effect of gap and embedding on their performance was not different from what was found for the TD group, children with DLD exhibited a diminished effect of case, suggesting reduced sensitivity to morphological case markers as processing cues. The implications of these results to theories of syntactic complexity and core deficits in DLD are discussed.

  12. Single acquisition electrical property mapping based on relative coil sensitivities: A proof-of-concept demonstration

    NARCIS (Netherlands)

    Marques, J.P.; Sodickson, D.K.; Ipek, O.; Collins, C.M.; Gruetter, R.

    2015-01-01

    PurposeAll methods presented to date to map both conductivity and permittivity rely on multiple acquisitions to compute quantitatively the magnitude of radiofrequency transmit fields, B-1(+). In this work, we propose a method to compute both conductivity and permittivity based solely on relative

  13. A prospective study on silicone breast implants and the silicone-related symptom complex.

    Science.gov (United States)

    Contant, C M E; Swaak, A J G; Obdeijn, A I M; van der Holt, B; Tjong Joe Wai, R; van Geel, A N; Eggermont, A M M

    2002-06-01

    This cohort study prospectively evaluated the prevalence of the silicone-related symptom complex (SRSC) in relation to antinuclear antibodies (ANA) and magnetic resonance imaging (MRI) of silicone breast implants (SBI) 1 year after implantation. A total of 57 women undergoing mastectomy followed by immediate breast reconstruction (IBR) and SBI between March 1995 and March 1997 at the University Hospital Rotterdam/Daniel den Hoed Cancer Centre, were prospectively evaluated. Just before and 1 year after IBR the sera of these women were tested for the presence of ANA and they were screened for the prevalence of SRSC-related symptoms by questionnaire. All prostheses were evaluated by MRI 1 month and 1 year after IBR. Just before operation 11% of the women had a Sjögren score of more than 2, whereas 30% had such a score 1 year after IBR ( P = 0.01). One year postoperatively women had significantly more RA/Raynaud-related complaints: 21% preoperatively versus 40% 1 year after IBR ( P = 0.03). Within the undefined complaints-related group 19% had a score of 2 or more preoperatively and 33% 1 year after IBR ( P = 0.09). There were no new cases of ANA positivity 1 year after IBR. The linguine sign was seen by MRI in three implants: one 1 month after IBR and two 1 year after IBR. There was no relation to changes in SRSC expression and these MRI findings. In conclusion, 1 year after SBI implantation women had more SRSC-related complaints, especially Sjögren's and RA/Raynaud's. Moreover there was no correlation between elevated SRSC expression and changes in the presence of ANA or changes in MRI of the SBI 1 year after IBR.

  14. Reconstructing the Surface Permittivity Distribution from Data Measured by the CONSERT Instrument aboard Rosetta: Method and Simulations

    Science.gov (United States)

    Plettemeier, D.; Statz, C.; Hegler, S.; Herique, A.; Kofman, W. W.

    2014-12-01

    One of the main scientific objectives of the Comet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT) aboard Rosetta is to perform a dielectric characterization of comet 67P/Chuyurmov-Gerasimenko's nucleus by means of a bi-static sounding between the lander Philae launched onto the comet's surface and the orbiter Rosetta. For the sounding, the lander part of CONSERT will receive and process the radio signal emitted by the orbiter part of the instrument and transmit a signal to the orbiter to be received by CONSERT. CONSERT will also be operated as bi-static RADAR during the descent of the lander Philae onto the comet's surface. From data measured during the descent, we aim at reconstructing a surface permittivity map of the comet at the landing site and along the path below the descent trajectory. This surface permittivity map will give information on the bulk material right below and around the landing site and the surface roughness in areas covered by the instrument along the descent. The proposed method to estimate the surface permittivity distribution is based on a least-squares based inversion approach in frequency domain. The direct problem of simulating the wave-propagation between lander and orbiter at line-of-sight and the signal reflected on the comet's surface is modelled using a dielectric physical optics approximation. Restrictions on the measurement positions by the descent orbitography and limitations on the instrument dynamic range will be dealt with by application of a regularization technique where the surface permittivity distribution and the gradient with regard to the permittivity is projected in a domain defined by a viable model of the spatial material and roughness distribution. The least-squares optimization step of the reconstruction is performed in such domain on a reduced set of parameters yielding stable results. The viability of the proposed method is demonstrated by reconstruction results based on simulated data.

  15. Ovipositor morphology and host relations of the Bactrocera tau complex (Diptera: Tephritidae in Thailand

    Directory of Open Access Journals (Sweden)

    Chalao Sumrandee

    2011-06-01

    Full Text Available The taxon, Bactrocera tau, is a complex of fruit flies that infest fruits of many species in the family Cucurbitaceaeas well as fruits from very different plant families in southeast Asia. Past mitotic karyotype studies of B. tau flies from differentgeographic location- and/or host-associated populations indicate there are nine forms present within the taxon in Thailand,which have been designated as B. tau forms A to I. In this study, ovipositor morphology was compared among sevenmembers of the B. tau complex using scanning electron microscopy. The flies could be placed into two main groups based onthe shape of the aculeus apex. The first group comprised B. tau forms C and I which have trilobed aculeus apices. The secondgroup included B. tau forms A, D, E, F and G, all of which have single-pointed apices. The latter five forms were furtherdivided on the basis of the sharpness of the aculeus apex into “medium” (A and E, “sharp” (D and G and “blunt” (F apices.Host fruit associations, fly aculeus apex shape and geographical region were overlain onto a molecular phylogeny previouslypublished for the B. tau group in Thailand. Cucurbitaceae fruits appear to be ancestral hosts for the B. tau complex whereasthe use of fruits of other plant families appeared late in the evolutionary history of this group. Forms with trilobed and singlepointedaculeus apices separated early in B. tau evolutionary history, but the split does not seem host related. Flies withmedium, sharp and blunt, simple-pointed aculeus apices showed no evident associations, being randomly distributed acrossthe phylogenetic tree. Bactrocera tau form A which infested fruits of nine Cucurbitaceae species was found in all fivesurveyed regions, whereas each of the other forms, which were restricted to 1-3 fruit species, were found in 1-2 regions.

  16. Molecular phylogeny of Glossodoris (Ehrenberg, 1831) nudibranchs and related genera reveals cryptic and pseudocryptic species complexes

    KAUST Repository

    Matsuda, Shayle B.; Gosliner, Terrence M.

    2017-01-01

    Chromodorid nudibranchs (Chromodorididae) are brightly coloured sea slugs that live in some of the most biodiverse and threatened coral reefs on the planet. However, the evolutionary relationships within this family have not been well understood, especially in the genus Glossodoris. Members of Glossodoris have experienced large-scale taxonomic instability over the last century and have been the subject of repeated taxonomic changes, in part due to morphological characters being the sole traditional taxonomic sources of data. Changing concepts of traditional generic boundaries based on morphology also have contributed to this instability. Despite recent advances in molecular systematics, many aspects of chromodorid taxonomy remain poorly understood, particularly at the traditional species and generic levels. In this study, 77 individuals comprising 32 previously defined species were used to build the most robust phylogenetic tree of Glossodoris and related genera using mitochondrial genes cytochrome c oxidase subunit I and 16S, and the nuclear gene 28S. Bayesian inference, maximum likelihood, and maximum parsimony analyses verify the most recent hypothesized evolutionary relationships within Glossodoris. Additionally, a pseudocryptic and cryptic species complex within Glossodoris cincta and a pseudocryptic complex within Glossodoris pallida emerged, and three new species of Doriprismatica are identified.

  17. Molecular phylogeny of Glossodoris (Ehrenberg, 1831) nudibranchs and related genera reveals cryptic and pseudocryptic species complexes

    KAUST Repository

    Matsuda, Shayle B.

    2017-03-01

    Chromodorid nudibranchs (Chromodorididae) are brightly coloured sea slugs that live in some of the most biodiverse and threatened coral reefs on the planet. However, the evolutionary relationships within this family have not been well understood, especially in the genus Glossodoris. Members of Glossodoris have experienced large-scale taxonomic instability over the last century and have been the subject of repeated taxonomic changes, in part due to morphological characters being the sole traditional taxonomic sources of data. Changing concepts of traditional generic boundaries based on morphology also have contributed to this instability. Despite recent advances in molecular systematics, many aspects of chromodorid taxonomy remain poorly understood, particularly at the traditional species and generic levels. In this study, 77 individuals comprising 32 previously defined species were used to build the most robust phylogenetic tree of Glossodoris and related genera using mitochondrial genes cytochrome c oxidase subunit I and 16S, and the nuclear gene 28S. Bayesian inference, maximum likelihood, and maximum parsimony analyses verify the most recent hypothesized evolutionary relationships within Glossodoris. Additionally, a pseudocryptic and cryptic species complex within Glossodoris cincta and a pseudocryptic complex within Glossodoris pallida emerged, and three new species of Doriprismatica are identified.

  18. Multistability and complex basins in a nonlinear duopoly with price competition and relative profit delegation.

    Science.gov (United States)

    Fanti, Luciano; Gori, Luca; Mammana, Cristiana; Michetti, Elisabetta

    2016-09-01

    In this article, we investigate the local and global dynamics of a nonlinear duopoly model with price-setting firms and managerial delegation contracts (relative profits). Our study aims at clarifying the effects of the interaction between the degree of product differentiation and the weight of manager's bonus on long-term outcomes in two different states: managers behave more aggressively with the rival (competition) under product complementarity and less aggressively with the rival (cooperation) under product substitutability. We combine analytical tools and numerical techniques to reach interesting results such as synchronisation and on-off intermittency of the state variables (in the case of homogeneous attitude of managers) and the existence of chaotic attractors, complex basins of attraction, and multistability (in the case of heterogeneous attitudes of managers). We also give policy insights.

  19. Multistability and complex basins in a nonlinear duopoly with price competition and relative profit delegation

    Science.gov (United States)

    Fanti, Luciano; Gori, Luca; Mammana, Cristiana; Michetti, Elisabetta

    2016-09-01

    In this article, we investigate the local and global dynamics of a nonlinear duopoly model with price-setting firms and managerial delegation contracts (relative profits). Our study aims at clarifying the effects of the interaction between the degree of product differentiation and the weight of manager's bonus on long-term outcomes in two different states: managers behave more aggressively with the rival (competition) under product complementarity and less aggressively with the rival (cooperation) under product substitutability. We combine analytical tools and numerical techniques to reach interesting results such as synchronisation and on-off intermittency of the state variables (in the case of homogeneous attitude of managers) and the existence of chaotic attractors, complex basins of attraction, and multistability (in the case of heterogeneous attitudes of managers). We also give policy insights.

  20. To address surface reaction network complexity using scaling relations machine learning and DFT calculations

    International Nuclear Information System (INIS)

    Ulissi, Zachary W.; Medford, Andrew J.; Bligaard, Thomas; Nørskov, Jens K.

    2017-01-01

    Surface reaction networks involving hydrocarbons exhibit enormous complexity with thousands of species and reactions for all but the very simplest of chemistries. We present a framework for optimization under uncertainty for heterogeneous catalysis reaction networks using surrogate models that are trained on the fly. The surrogate model is constructed by teaching a Gaussian process adsorption energies based on group additivity fingerprints, combined with transition-state scaling relations and a simple classifier for determining the rate-limiting step. The surrogate model is iteratively used to predict the most important reaction step to be calculated explicitly with computationally demanding electronic structure theory. Applying these methods to the reaction of syngas on rhodium(111), we identify the most likely reaction mechanism. Lastly, propagating uncertainty throughout this process yields the likelihood that the final mechanism is complete given measurements on only a subset of the entire network and uncertainty in the underlying density functional theory calculations.

  1. Dystroglycan and muscular dystrophies related to the dystrophin-glycoprotein complex.

    Science.gov (United States)

    Sciandra, Francesca; Bozzi, Manuela; Bianchi, Marzia; Pavoni, Ernesto; Giardina, Bruno; Brancaccio, Andrea

    2003-01-01

    Dystroglycan (DG) is an adhesion molecule composed of two subunits, alpha and beta, that are produced by the post-translational cleavage of a single precursor molecule. DG is a pivotal component of the dystrophin-glycoprotein complex (DGC), which connects the extracellular matrix to the cytoskeleton in skeletal muscle and many other tissues. Some muscular dystrophies are caused by mutations of DGC components, such as dystrophin, sarcoglycan or laminin-2, or also of DGC-associated molecules, such as caveolin-3. DG-null mice died during early embriogenesis and no neuromuscular diseases directly associated to genetic abnormalities of DG were identified so far. However, DG plays a crucial role for muscle integrity since its targeting at the sarcolemma is often perturbed in DGC-related neuromuscular disorders.

  2. The Gd14Ag51 structure type and its relation to some complex amalgam structures

    International Nuclear Information System (INIS)

    Tambornino, Frank; Sappl, Jonathan; Hoch, Constantin

    2015-01-01

    Highlights: • The Gd 14 Ag 51 structure type has been revisited on the basis of single crystal diffraction data. • Symmetry analysis from electron density and TEM shows the space group P6/m to be true. • Gd 14 Ag 51 shows good metallic behaviour. • Structure relations to alkali, alkaline-earth and rare-earth metal amalgams can be established. • Complexity values for the RE 14 Ag 51 structure family were calculated. - Abstract: A plethora of binary and ternary intermetallic compounds has been assigned to the Gd 14 Ag 51 structure type, crystallising in the hexagonal system (space group P6/m, a = 1264.30(18) pm, c = 933.58(11) pm for Gd 14 Ag 51 ). Starting in the late 1960s, much work has been invested in the structural elucidation of these crystal structures. However, reliable single crystal data are scarce, and most structure type assignments have been performed merely on the basis of powder data. We have redetermined four representatives of the binary RE 14 Ag 51 structure type (RE = Y, Ce, Gd, Tb) with modern high-precision single crystal X-ray methods. The assignment of the Gd 14 Ag 51 structure type to space group P6/m was additionally verified by careful analysis of high resolution transmission electron micrographs. We emphasise the close relation of the Gd 14 Ag 51 structure type to the structures of some recently described amalgams of similar composition focussing on disorder phenomena and structural complexity. Furthermore, we provide detailed information on synthesis as well as electrical and magnetic properties for Gd 14 Ag 51 , the parent compound of this structure family

  3. Navigating the complexities of qualitative comparative analysis: case numbers, necessity relations, and model ambiguities.

    Science.gov (United States)

    Thiem, Alrik

    2014-12-01

    In recent years, the method of Qualitative Comparative Analysis (QCA) has been enjoying increasing levels of popularity in evaluation and directly neighboring fields. Its holistic approach to causal data analysis resonates with researchers whose theories posit complex conjunctions of conditions and events. However, due to QCA's relative immaturity, some of its technicalities and objectives have not yet been well understood. In this article, I seek to raise awareness of six pitfalls of employing QCA with regard to the following three central aspects: case numbers, necessity relations, and model ambiguities. Most importantly, I argue that case numbers are irrelevant to the methodological choice of QCA or any of its variants, that necessity is not as simple a concept as it has been suggested by many methodologists, and that doubt must be cast on the determinacy of virtually all results presented in past QCA research. By means of empirical examples from published articles, I explain the background of these pitfalls and introduce appropriate procedures, partly with reference to current software, that help avoid them. QCA carries great potential for scholars in evaluation and directly neighboring areas interested in the analysis of complex dependencies in configurational data. If users beware of the pitfalls introduced in this article, and if they avoid mechanistic adherence to doubtful "standards of good practice" at this stage of development, then research with QCA will gain in quality, as a result of which a more solid foundation for cumulative knowledge generation and well-informed policy decisions will also be created. © The Author(s) 2014.

  4. A laser-spectroscopy complex for fluorescent diagnostics and photodynamic therapy of age-related macula degeneration

    Science.gov (United States)

    Shevchik, S. A.; Meerovich, Gennadii A.; Budzinskaya, M. V.; Ermakova, N. A.; Kharnas, Sergey S.; Loschenov, Victor B.

    2004-06-01

    A laser-spectroscopy complex was developed for fluorescent diagnostics and photodynamic therapy of age related macula degeneration using the Russian photosensitizer Photosense. The complex is based on slit lamp which was additionally equipped with an optical adapter, and the video adapter allows to combine the procedure of photodynamic therapy and the control of its carrying in the frame work of one procedure. The sensitivity and spatial resolution of the complex were investigated using a special test object. The availability of the developed complex and Photosense itself was examined on experimental animals.

  5. Clinical spectrum and diagnostic value of antibodies against the potassium channel related protein complex.

    Science.gov (United States)

    Montojo, M T; Petit-Pedrol, M; Graus, F; Dalmau, J

    2015-06-01

    Antibodies against a protein complex that includes voltage-gated potassium channels (VGKC) have been reported in patients with limbic encephalitis, peripheral nerve hyperexcitability, Morvan's syndrome, and a large variety of neurological syndromes. In this article, a review is presented of the syndromes associated with antibodies against VGKC-related proteins and the main antigens of this protein complex, the proteins LGI1 (leucine rich glioma inactivated protein 1) and Caspr2 (contactin-associated protein-like 2). The conceptual problems and clinical implications of the description of antibodies against VGKC-related proteins other than LGI1 and Caspr2 are also discussed. Although initial studies indicated the occurrence of antibodies against VGKC, recent investigations have shown that the main antigens are a neuronal secreted protein known as LGI1 which modulates synaptic excitability, and a protein called Caspr2 located on the cell surface and processes of neurons of different brain regions, and at the juxtaparanodal region of myelinated axons. While antibodies against LGI1 preferentially associate with classical limbic encephalitis, antibodies against Caspr2 associate with a wider spectrum of symptoms, including Morvan's syndrome, peripheral nerve hyperexcitability or neuromyotonia, and limbic or more extensive encephalitis. In addition there are reports of patients with antibodies against VGKC-related proteins that are different from LGI1 or Caspr2. In these cases, the identity and location of the antigens are unknown, the syndrome association is not specific, and the response to treatment uncertain. The discovery of antigens such as LGI1 and Caspr2 has resulted in a clinical and molecular definition of the broad group of diseases previously attributed to antibodies against VGKC. Considering the literature that describes the presence of antibodies against VGKC other than LGI1 and Caspr2 proteins, we propose a practical algorithm for the diagnosis and treatment

  6. Teacher formation related to socio-scientific issues: complexity, contributions and limitations of an educational practice

    Directory of Open Access Journals (Sweden)

    Mariuce Campos de Moraes

    2015-12-01

    Full Text Available This reflection refers to teacher formation related to socio-scientific issues. Whereas such matters take into account the impact of scientific development in society, including ethical aspects and encompass dilemmas involving a wide range of prospects for its resolution, we propose analysis of the complexity that is inherent in their teaching. Thus, we aimed to analyze different spaces and teaching time that produce and are produced in close linkage between theory and practice, as well as their contributions and limitations. The study required a dynamic conversation system that led to the analysis indicators. The issue of sustainability was shown to be feasible for educational planning as cover technical and scientific knowledge, ethical, social and economic pressures. The collective production allowed understand arguments and reflective-creative processes. The lived relations in schools has accompanied and limited the ideas expressed on the socio-scientific issues. We understand that the simultaneity of research and reflection in the sociocultural context has strengthened teacher formation.

  7. Outcome of limbic encephalitis with VGKC-complex antibodies: relation to antigenic specificity.

    Science.gov (United States)

    Malter, M P; Frisch, C; Schoene-Bake, J C; Helmstaedter, C; Wandinger, K P; Stoecker, W; Urbach, H; Surges, R; Elger, C E; Vincent, A V; Bien, C G

    2014-09-01

    In limbic encephalitis (LE) with antibodies (Abs) to the voltage-gated potassium channel complex (VGKC), the Abs are mainly directed to the VGKC-complex proteins, leucine-rich, glioma inactivated 1 protein (LGI1) or contactin-associated protein-like 2 (CASPR-2) or neither. Here, we relate the outcomes of VGKC-LE patients to the presence of Abs to LGI1, CASPR-2 or neither antigen (LGI1/CASPR-2-Ab(-)). Clinical, neuropsychology and MRI data were obtained from patient records for all LE patients from the Bonn Epilepsy Centre positive for VGKC-Abs by radioimmunoprecipitation assay between 2002 and 2011. Eighteen VGKC-LE patients were identified: nine patients (50 %) had LGI1-Abs, three (16 %) had CASPR-2-Abs; and six (33 %) were negative for both LGI1- and CASPR-2-Abs. At first assessment, the groups did not differ clinically or radiologically, but faciobrachial dystonic seizures were only observed in two LGI1-Ab(+) patients. All patients received monthly intravenous methylprednisolone (MP) pulses. At the most recent follow up (median 26 months), thirteen (72 %) were seizure-free, and seizure-freedom rates did not differ between the Ab groups. Hippocampal atrophy had developed in 7/9 LGI1-Ab(+) patients, but in none of the CASPR-2-Ab(+) or LGI/CASPR-2-Ab(-) patients (p = 0.003). While all subgroups improved, memory scores only normalized in six patients (33 %) and LGI1-Ab(+) patients were left with significantly poorer memory than the other two subgroups. Most VGKC-LE patients become seizure-free with pulsed monthly MP, but memory outcome is less favourable. Hippocampal atrophy and poor memory recovery is common in patients with LGI1-Abs and suggests permanent functional damage. More intense immunotherapies could improve outcomes in LGI1-Ab(+)-LE.

  8. NEW CONSTRAINTS ON A COMPLEX RELATION BETWEEN GLOBULAR CLUSTER COLORS AND ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    Powalka, Mathieu; Lançon, Ariane [Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, F-67000 Strasbourg (France); Puzia, Thomas H.; Alamo-Martínez, Karla; Ángel, Simón [Institute of Astrophysics, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 7820436 Macul, Santiago (Chile); Peng, Eric W.; Lim, Sungsoon [Department of Astronomy, Peking University, Beijing 100871 (China); Schönebeck, Frederik; Grebel, Eva K. [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstraße 12-14, D-69120 Heidelberg (Germany); Blakeslee, John P.; Côté, Patrick; Ferrarese, Laura; Gwyn, S. D. J. [Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC V9E 2E7 (Canada); Cuillandre, Jean-Charles; Duc, Pierre-Alain [AIM Paris Saclay, CNRS/INSU, CEA/Irfu, Université Paris Diderot, Orme des Merisiers, F-91191 Gif-sur-Yvette Cedex (France); Durrell, Patrick [Department of Physics and Astronomy, Youngstown State University, One University Plaza, Youngstown, OH 44555 (United States); Guhathakurta, Puragra [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Kuntschner, Harald, E-mail: mathieu.powalka@astro.unistra.fr [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany); and others

    2016-09-20

    We present an analysis of high-quality photometry for globular clusters (GCs) in the Virgo cluster core region, based on data from the Next Generation Virgo Cluster Survey (NGVS) pilot field, and in the Milky Way (MW), based on Very Large Telescope/X-Shooter spectrophotometry. We find significant discrepancies in color–color diagrams between sub-samples from different environments, confirming that the environment has a strong influence on the integrated colors of GCs. GC color distributions along a single color are not sufficient to capture the differences we observe in color–color space. While the average photometric colors become bluer with increasing radial distance to the cD galaxy M87, we also find a relation between the environment and the slope and intercept of the color–color relations. A denser environment seems to produce a larger dynamic range in certain color indices. We argue that these results are not due solely to differential extinction, Initial Mass Function variations, calibration uncertainties, or overall age/metallicity variations. We therefore suggest that the relation between the environment and GC colors is, at least in part, due to chemical abundance variations, which affect stellar spectra and stellar evolution tracks. Our results demonstrate that stellar population diagnostics derived from model predictions which are calibrated on one particular sample of GCs may not be appropriate for all extragalactic GCs. These results advocate a more complex model of the assembly history of GC systems in massive galaxies that goes beyond the simple bimodality found in previous decades.

  9. NEW CONSTRAINTS ON A COMPLEX RELATION BETWEEN GLOBULAR CLUSTER COLORS AND ENVIRONMENT

    International Nuclear Information System (INIS)

    Powalka, Mathieu; Lançon, Ariane; Puzia, Thomas H.; Alamo-Martínez, Karla; Ángel, Simón; Peng, Eric W.; Lim, Sungsoon; Schönebeck, Frederik; Grebel, Eva K.; Blakeslee, John P.; Côté, Patrick; Ferrarese, Laura; Gwyn, S. D. J.; Cuillandre, Jean-Charles; Duc, Pierre-Alain; Durrell, Patrick; Guhathakurta, Puragra; Kuntschner, Harald

    2016-01-01

    We present an analysis of high-quality photometry for globular clusters (GCs) in the Virgo cluster core region, based on data from the Next Generation Virgo Cluster Survey (NGVS) pilot field, and in the Milky Way (MW), based on Very Large Telescope/X-Shooter spectrophotometry. We find significant discrepancies in color–color diagrams between sub-samples from different environments, confirming that the environment has a strong influence on the integrated colors of GCs. GC color distributions along a single color are not sufficient to capture the differences we observe in color–color space. While the average photometric colors become bluer with increasing radial distance to the cD galaxy M87, we also find a relation between the environment and the slope and intercept of the color–color relations. A denser environment seems to produce a larger dynamic range in certain color indices. We argue that these results are not due solely to differential extinction, Initial Mass Function variations, calibration uncertainties, or overall age/metallicity variations. We therefore suggest that the relation between the environment and GC colors is, at least in part, due to chemical abundance variations, which affect stellar spectra and stellar evolution tracks. Our results demonstrate that stellar population diagnostics derived from model predictions which are calibrated on one particular sample of GCs may not be appropriate for all extragalactic GCs. These results advocate a more complex model of the assembly history of GC systems in massive galaxies that goes beyond the simple bimodality found in previous decades.

  10. Indoor radon related to uranium in granitoids of the Central Bohemian plutonic complex

    International Nuclear Information System (INIS)

    Barnet, I.; Fojtikova, I.

    2004-01-01

    The study is based on the indoor radon data (one year measurements, Kodak LR 115 track etch detectors), vectorized geological maps 1:50000, vectorized coordinates of dwellings and uranium data for granitoid types of the Central Bohemian Plutonic Complex (CBPC). Using ArcGis 8.2 programme, the position of 16145 dwellings was linked to a geological database covering the CBPC (approx. 3200 km 2 ), and the type of underlying rock type was specified for each house. The resulting databases enabled us to calculate the mean EEC indoor Rn data for particular granitoid types and to study the relationship between the indoor Rn and the U concentrations. The petrogenetically variable CBPC was emplaced during Variscan orogenesis (330-350 Ma) and is among the most radioactive rock types within the Bohemian Massif. A long-term process of CBPC genesis resulted in more than 20 granitoid types, differing by their petrogenetic characteristics as well as mineralogical and chemical composition, including uranium concentration. The relation between the mean indoor radon values and uranium concentrations in particular rock types was examined. A positive regression between indoor Rn and uranium as the source of Rn soil gas clearly demonstrates how regional geology influences the indoor radon activity concentration in dwellings. The highest indoor Rn concentrations were observed in the Sedlcany granodiorite and Certovo bremeno syenite, where also the highest gamma dose rates (150-210 nGy.h -1 ) within all granitoid types in the Czech Republic were observed. The two rock types differ from other granitoids by a relatively high zircon concentration, which is the main source of U and subsequently of soil gas Rn being released from the bedrock. The lower indoor Rn values of Certovo bremeno syenite which do not correspond with the high U concentrations can be explained by a relatively low permeability of its clayey weathering crust. This feature was also observed for soil gas radon concentration

  11. Thermodynamic and electrochemical properties of some rare earth cryptates and related complexes in propylene carbonate

    International Nuclear Information System (INIS)

    Loufouilou, E.L.

    1986-03-01

    The stability of trivalent lanthanide complexes with [1]-cryptand 22 and [2]-cryptands 222 and 211 and also tris (3.6- dioxa heptyl) amine (TDHA) is studied in propylene carbonate solution by potentiometry with Ag + as an auxiliary cation. Complexation enthalpies and entropies are determined for other complexes of some trivalent lanthanides (La, Er, Pr and Eu) with ligands 222, 221, 211, 22, 21, 18C6 and TDHA. [1]- and [2]- crytands are complexing agents more powerful than TDHA and crown-ethers 15C6 and 18C6. For ligands containing nitrogen complexe stability increase with RE atomic number but decrease for crown-ethers. In propylene carbonate complexes are stabilized by enthalpic effects, entropic contribution is variable. Polarographic reduction of samarium cryptate with ligand 222, 221 and 22 in propylene carbonate is reversible as in more solvating solvents water and methanol. Mixed complexes are formed with chlorides and this cryptate system is more difficult to reduce [fr

  12. Direct measurement of the static and transient magneto-optical permittivity of cobalt across the entire M -edge in reflection geometry by use of polarization scanning

    Science.gov (United States)

    Zusin, Dmitriy; Tengdin, Phoebe M.; Gopalakrishnan, Maithreyi; Gentry, Christian; Blonsky, Adam; Gerrity, Michael; Legut, Dominik; Shaw, Justin M.; Nembach, Hans T.; Silva, T. J.; Oppeneer, Peter M.; Kapteyn, Henry C.; Murnane, Margaret M.

    2018-01-01

    The microscopic state of a magnetic material is characterized by its resonant magneto-optical response through the off-diagonal dielectric tensor component ɛx y. However, the measurement of the full complex ɛx y in the extreme ultraviolet spectral region covering the M absorption edges of 3 d ferromagnets is challenging due to the need for either a careful polarization analysis, which is complicated by a lack of efficient polarization analyzers, or scanning the angle of incidence in fine steps. Here, we propose and demonstrate a technique to extract the complex resonant permittivity ɛx y simply by scanning the polarization angle of linearly polarized high harmonics to measure the magneto-optical asymmetry in reflection geometry. Because this technique is more practical and faster to experimentally implement than previous approaches, we can directly measure the full time evolution of ɛx y(t ) during laser-induced demagnetization across the entire M2 ,3 absorption edge of cobalt with femtosecond time resolution. We find that for polycrystalline Co films on an insulating substrate, the changes in ɛx y are uniform throughout the spectrum, to within our experimental precision. This result suggests that, in the regime of strong demagnetization, the ultrafast demagnetization response is primarily dominated by magnon generation. We estimate the contribution of exchange-splitting reduction to the ultrafast demagnetization process to be no more than 25%.

  13. Influence of particle arrangement on the permittivity of an elastomeric composite

    Directory of Open Access Journals (Sweden)

    Peiying J. Tsai

    2017-01-01

    Full Text Available Elastomers are used as dielectric layers contained between the parallel conductive plates of capacitors. The introduction of filler particles into an elastomer changes its permittivity ε. When particle organization in a composite is intentionally varied, this alters its capacitance. Using numerical simulations, we examine how conductive particle chains introduced into polydimethylsiloxane (PDMS alter ε. The effects of filler volume fraction ψ, interparticle d and interchain spacing a, zigzag angle θ between adjacent particles and overall chain orientation, particle size r, and clearance h between particles and the conductive plates are characterized. When filler particles are organized into chainlike structures rather than being just randomly distributed in the elastomer matrix, ε increases by as much as 85%. When particles are organized into chainlike forms, ε increases with increasing ψ and a, but decreases with increasing d and θ. A composite containing smaller particles has a higher ε when ψ<9% while larger particles provide greater enhancement when ψ is larger than that value. To enhance ε, adjacent particles must be interconnected and the overall chain direction should be oriented perpendicular to the conductive plates. These results are useful for additive manufacturing on electrical applications of elastomeric composites.

  14. Transformation optics and metamaterials at infrared wavelength: engineering of permittivity and permeability

    Science.gov (United States)

    Ghasemi, Rasta; Degiron, Aloyse; Leroux, Xavier; Lupu, Anatole; de Lustrac, André

    2013-05-01

    The transformation optics was introduced by J. Pendry and U. Leonhardt in 2006 [1,2]. In this method an initial space is transformed into a new space and this transformed space can be materialized by a material, which the electromagnetic parameters can be deduced from the metric of the transformed space. In the general case the electromagnetic parameters are anisotropic tensors. At microwave frequencies these materials can be realized using classical metamaterials like SRR form J. Pendry or ELC from D. Smith [3]. At infrared wavelengths this realization is a challenge because the dimensions of the metamaterials are much smaller than the wavelength and become nanometric. Then the design of these metamaterials must be simplified and original methods must be developed to allow the realization of these metamaterials with controlled electromagnetic properties. In this paper we describe the realization of a multilayer metamaterial working at infrared wavelength, which the permittivity and the permeability can be adjusted separately. We give some examples of realized multilayer materials operating around 150THz, with a comparison between the results of full wave simulations of these materials and their characterizations using a Fourier Transform Infrared Spectrometer.

  15. Enhancing Self-Assembly in Cellulose Nanocrystal Suspensions Using High-Permittivity Solvents.

    Science.gov (United States)

    Bruckner, Johanna R; Kuhnhold, Anja; Honorato-Rios, Camila; Schilling, Tanja; Lagerwall, Jan P F

    2016-09-27

    Helical liquid crystal self-assembly in suspensions of cellulose nanocrystals (CNCs), bioderived nanorods exhibiting excellent mechanical and optical properties, opens attractive routes to sustainable production of advanced functional materials. For convenience, in most studies until now, the CNCs were suspended in water, leaving a knowledge gap concerning the influence of the solvent. Using a novel approach for aggregation-free solvent exchange in CNC suspensions, here we show that protic solvents with a high dielectric permittivity εr significantly speed up self-assembly (from days to hours) at high CNC mass fraction and reduce the concentration dependence of the helix period (variation reducing from more than 30 μm to less than 1 μm). Moreover, our computer simulations indicate that the degree of order at constant CNC content increases with increasing εr, leading to a shorter pitch and a reduced threshold for liquid crystallinity. In low-εr solvents, the onset of long-range orientational order is coupled to kinetic arrest, preventing the formation of a helical superstructure. Our results show that the choice of solvent is a powerful parameter for tuning the behavior of CNC suspensions, enhancing our ability to control the self-assembly and thereby harvesting valuable novel cellulose-based materials.

  16. Influence of particle arrangement on the permittivity of an elastomeric composite

    Science.gov (United States)

    Tsai, Peiying J.; Nayak, Suchitra; Ghosh, Suvojit; Puri, Ishwar K.

    2017-01-01

    Elastomers are used as dielectric layers contained between the parallel conductive plates of capacitors. The introduction of filler particles into an elastomer changes its permittivity ɛ. When particle organization in a composite is intentionally varied, this alters its capacitance. Using numerical simulations, we examine how conductive particle chains introduced into polydimethylsiloxane (PDMS) alter ɛ. The effects of filler volume fraction ψ, interparticle d and interchain spacing a, zigzag angle θ between adjacent particles and overall chain orientation, particle size r, and clearance h between particles and the conductive plates are characterized. When filler particles are organized into chainlike structures rather than being just randomly distributed in the elastomer matrix, ɛ increases by as much as 85%. When particles are organized into chainlike forms, ɛ increases with increasing ψ and a, but decreases with increasing d and θ. A composite containing smaller particles has a higher ɛ when ψ <9 % while larger particles provide greater enhancement when ψ is larger than that value. To enhance ɛ, adjacent particles must be interconnected and the overall chain direction should be oriented perpendicular to the conductive plates. These results are useful for additive manufacturing on electrical applications of elastomeric composites.

  17. Yttrium scandate thin film as alternative high-permittivity dielectric for germanium gate stack formation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Cimang, E-mail: cimang@adam.t.u-tokyo.ac.jp; Lee, Choong Hyun; Nishimura, Tomonori; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan); JST, CREST, 7-3-1 Hongo, Tokyo 113-8656 (Japan)

    2015-08-17

    We investigated yttrium scandate (YScO{sub 3}) as an alternative high-permittivity (k) dielectric thin film for Ge gate stack formation. Significant enhancement of k-value is reported in YScO{sub 3} comparing to both of its binary compounds, Y{sub 2}O{sub 3} and Sc{sub 2}O{sub 3}, without any cost of interface properties. It suggests a feasible approach to a design of promising high-k dielectrics for Ge gate stack, namely, the formation of high-k ternary oxide out of two medium-k binary oxides. Aggressive scaling of equivalent oxide thickness (EOT) with promising interface properties is presented by using YScO{sub 3} as high-k dielectric and yttrium-doped GeO{sub 2} (Y-GeO{sub 2}) as interfacial layer, for a demonstration of high-k gate stack on Ge. In addition, we demonstrate Ge n-MOSFET performance showing the peak electron mobility over 1000 cm{sup 2}/V s in sub-nm EOT region by YScO{sub 3}/Y-GeO{sub 2}/Ge gate stack.

  18. Time domain reflectometry-measuring dielectric permittivity to detect soil non-acqeous phase liquids contamination-decontamination processes

    Directory of Open Access Journals (Sweden)

    A. Comegna

    2013-09-01

    Full Text Available Contamination of soils with non-aqueous phase liquids (NAPL constitutes a serious geo-environmental problem, given the toxicity level and high mobility of these organic compounds. To develop effective decontamination methods, characterisation and identification of contaminated soils are needed. The objective of this work is to explore the potential of dielectric permittivity measurements to detect the presence of NAPLs in soils. The dielectric permittivity was measured by Time Domain Reflectometry method (TDR in soil samples with either different volumetric content of water (w and NAPL (NAPL or at different stages during immiscible displacement test carried out with two different flushing solutions. A mixing model proposed by Francisca and Montoro, was calibrated to estimate the volume fraction of contaminant present in soil. Obtained results, showed that soil contamination with NAPL and the monitoring of immiscible fluid displacement, during soil remediation processes, can be clearly identified from dielectric measurements.

  19. Interpenetrated polymer networks based on commercial silicone elastomers and ionic networks with high dielectric permittivity and self-healing properties

    DEFF Research Database (Denmark)

    Ogliani, Elisa; Yu, Liyun; Skov, Anne Ladegaard

    the applicability. One method used to avoid this limitation is to increase the dielectric permittivity of the material in order to improve the actuation response at a given field. Recently, interpenetrating polymer networks (IPNs) based on covalently cross-linked commercial silicone elastomers and ionic networks...... from amino- and carboxylic acid- functional silicones have been designed[2] (Figure 1). This novel system provides both the mechanical stability and the high breakdown strength given by the silicone part of the IPNs and the high permittivity and the softening effect of the ionic network. Thus......,1 Hz), and the commercial elastomers RT625 and LR3043/30 provide thebest viscoelastic properties to the systems, since they maintain low viscous losses upon addition of ionic network. The values ofthe breakdown strength in all cases remain higher than that of the reference pure PDMS network (ranging...

  20. Dispersion of Dielectric Permittivity in a Nanocrystalline Cellulose-Triglycine Sulfate Composite at Low and Ultralow Frequencies

    Science.gov (United States)

    Thu'o'ng, Nguyen Hoai; Sidorkin, A. S.; Milovidova, S. D.

    2018-03-01

    The dispersion of dielectric permittivity in nanocrystalline cellulose-triglycine sulfate composites is studied in the range of frequencies from 10-3 to 106 Hz, at temperatures varying from room temperature to the temperature of phase transition in this composite (54°C), in weak electric fields (1 V cm-1). Two behaviors for the dielectric dispersion are identified in the studied frequency range: at ultralow frequencies (10-3-10 Hz), the dispersion is due to Maxwell-Wagner polarization, while at higher frequencies (10-106 Hz), the dispersion is due to the movement of domain walls in the embedded triglycine sulfate crystallites. An additional peak in the temperature-dependent profiles of dielectric permittivity is detected at lower temperatures in freshly prepared samples of the considered composite; we associate it with the presence of residual water in these samples.

  1. Development of a symptoms questionnaire for complex regional pain syndrome and potentially related illnesses: the Trauma Related Neuronal Dysfunction Symptoms Inventory

    NARCIS (Netherlands)

    Collins, S.; van Hilten, J.J.; Marinus, J.J.; Zuurmond, W.W.A.; de Lange, J.J.; Perez, R.S.G.M.

    2008-01-01

    Collins S, van Hilten JJ, Marinus J, Zuurmond WW, de Lange JJ, Perez RS. Development of a symptoms questionnaire for complex regional pain syndrome and potentially related illnesses: the Trauma Related Neuronal Dysfunction Symptoms Inventory. Objective: To develop a questionnaire to evaluate

  2. Complex resistivity spectra in relation to multiscale pore geometry in carbonates and mixed-siliciclastic rocks

    Science.gov (United States)

    Norbisrath, Jan Henrik

    properties. Specifically, frequency dispersion of complex resistivity in the kHz range is used as input for a new model to predict cementation factor and permeability in a wide variety of core plug samples. The underlying concept that relates CRS to flow properties is that both are related to pore geometry. CRS are linked to pore geometry by interfacial polarization effects at the fluid-rock boundary that control the phase and amplitude shift of an applied alternating current. Larger interfacial area results in higher phase shifts, but also indicates a more intricate pore structure that often results in lower permeability and higher cementation factors. The findings from this dissertation imply that (1) the CRS prediction method greatly improves estimates of cementation factors and permeability in carbonate, dolomite, and mixed siliciclastic rocks, (2) there are at least four distinct microporosity types in carbonate rocks, which have great impact on cementation factors and permeability, (3) nanopore geometry has a small impact on electrical flow properties in mudrocks where the main control on cementation factors is porosity, and (4) all sedimentary limestone and mixed carbonate-siliciclastic rocks have power law pore size distributions.

  3. Silver Nanowire/MnO2 Nanowire Hybrid Polymer Nanocomposites: Materials with High Dielectric Permittivity and Low Dielectric Loss.

    Science.gov (United States)

    Zeraati, Ali Shayesteh; Arjmand, Mohammad; Sundararaj, Uttandaraman

    2017-04-26

    This study reports the fabrication of hybrid nanocomposites based on silver nanowire/manganese dioxide nanowire/poly(methyl methacrylate) (AgNW/MnO 2 NW/PMMA), using a solution casting technique, with outstanding dielectric permittivity and low dielectric loss. AgNW was synthesized using the hard-template technique, and MnO 2 NW was synthesized employing a hydrothermal method. The prepared AgNW:MnO 2 NW (2.0:1.0 vol %) hybrid nanocomposite showed a high dielectric permittivity (64 at 8.2 GHz) and low dielectric loss (0.31 at 8.2 GHz), which are among the best reported values in the literature in the X-band frequency range (8.2-12.4 GHz). The superior dielectric properties of the hybrid nanocomposites were attributed to (i) dimensionality match between the nanofillers, which increased their synergy, (ii) better dispersion state of AgNW in the presence of MnO 2 NW, (iii) positioning of ferroelectric MnO 2 NW in between AgNWs, which increased the dielectric permittivity of nanodielectrics, thereby increasing dielectric permittivity of the hybrid nanocomposites, (iv) barrier role of MnO 2 NW, i.e., cutting off the contact spots of AgNWs and leading to lower dielectric loss, and (v) AgNW aligned structure, which increased the effective surface area of AgNWs, as nanoelectrodes. Comparison of the dielectric properties of the developed hybrid nanocomposites with the literature highlights their great potential for flexible capacitors.

  4. Dielectric permittivity in weakly concentrated SrTiO.sub.3./sub.:Mn crystals and ceramics

    Czech Academy of Sciences Publication Activity Database

    Trepakov, Vladimír; Savinov, Maxim; Železný, Vladimír; Pokorný, Jan; Syrnikov, P.; Azzoni, C. B.; Galinetto, P.; Mozzati, M. C.; Badalyan, A.; Deyneka, Alexander; Jastrabík, Lubomír

    2007-01-01

    Roč. 93, č. 1 (2007), 012017/1-012017/6 ISSN 1742-6588 R&D Projects: GA AV ČR KAN301370701; GA AV ČR 1QS100100563; GA MŠk(CZ) 1M06002 Institutional research plan: CEZ:AV0Z10100521; CEZ:AV0Z10100522 Keywords : dielectric permittivity * SrTiO 3 :Mn * crystals and ceramics Subject RIV: BM - Solid Matter Physics ; Magnetism

  5. Development of 16 Microsatellite Markers within the Camassia (Agavaceae Species Complex and Amplification in Related Taxa

    Directory of Open Access Journals (Sweden)

    Theresa M. Culley

    2013-07-01

    Full Text Available Premise of the study: The North American genus Camassia is an ecologically important group whose variability and evolution are little understood, being influenced by hybridization and geographic isolation. We developed microsatellite markers to investigate patterns of gene flow, population structure, and taxonomic relationships within this group. Methods and Results: Using a traditional approach with biotin-labeled probes, we developed 16 microsatellite primers in three species of Camassia: C. howellii, C. leichtlinii, and C. quamash. The number of alleles per locus averaged 3.94 per species, and levels of heterozygosity ranged from 0.000 to 1.00 and 0.033 to 0.917 for observed and expected heterozygosities, respectively. All primers amplified to varying extents in additional species (C. angusta, C. cusickii, C. scilloides and in putative species in a related genus (Hastingsia alba, H. atropurpurea, H. bracteosa, H. serpentinicola. Conclusions: These microsatellite markers exhibit variation and are useful for ongoing studies of integrative taxonomy and population differentiation within this species complex.

  6. Understanding Student Cognition about Complex Earth System Processes Related to Climate Change

    Science.gov (United States)

    McNeal, K. S.; Libarkin, J.; Ledley, T. S.; Dutta, S.; Templeton, M. C.; Geroux, J.; Blakeney, G. A.

    2011-12-01

    The Earth's climate system includes complex behavior and interconnections with other Earth spheres that present challenges to student learning. To better understand these unique challenges, we have conducted experiments with high-school and introductory level college students to determine how information pertaining to the connections between the Earth's atmospheric system and the other Earth spheres (e.g., hydrosphere and cryosphere) are processed. Specifically, we include psychomotor tests (e.g., eye-tracking) and open-ended questionnaires in this research study, where participants were provided scientific images of the Earth (e.g., global precipitation and ocean and atmospheric currents), eye-tracked, and asked to provide causal or relational explanations about the viewed images. In addition, the students engaged in on-line modules (http://serc.carleton.edu/eslabs/climate/index.html) focused on Earth system science as training activities to address potential cognitive barriers. The developed modules included interactive media, hands-on lessons, links to outside resources, and formative assessment questions to promote a supportive and data-rich learning environment. Student eye movements were tracked during engagement with the materials to determine the role of perception and attention on understanding. Students also completed a conceptual questionnaire pre-post to determine if these on-line curriculum materials assisted in their development of connections between Earth's atmospheric system and the other Earth systems. The pre-post results of students' thinking about climate change concepts, as well as eye-tracking results, will be presented.

  7. The Arabidopsis-related halophyte Thellungiella halophila: boron tolerance via boron complexation with metabolites?

    Science.gov (United States)

    Lamdan, Netta Li; Attia, Ziv; Moran, Nava; Moshelion, Menachem

    2012-04-01

    Tolerance to boron (B) is still not completely understood. We tested here the hypothesis that Thellungiella halophila, an Arabidopsis thaliana-related 'extremophile' plant, with abundance of B in its natural environment, is tolerant to B, and examined the potential mechanisms of this tolerance. With 1-10 mm B applied ([B](ext)) to Thellungiella and Arabidopsis grown in hydroponics, the steady-state accumulated B concentration ([B](int)) in the root was below [B](ext), and was similar in both, suggesting both extrude B actively. Whether grown in soil or hydroponically, the shoot [B](int) was higher in Arabidopsis than in Thellungiella, suggesting more effective net B exclusion by Thellungiella root. Arabidopsis exhibited toxicity symptoms including reduced shoot fresh weight (FW), but Thellungiella was not affected, even at similar levels of shoot-accumulated [B](int) (about 10 to 40 mm B in 'shoot water'), suggesting additional B tolerance mechanism in Thellungiella shoot. At [B](ext) = 5 mm, the summed shoot concentration of the potentially B-binding polyhydroxyl metabolites (malic acid, fructose, glucose, sucrose and citric acid) in Arabidopsis was below [B](int) , but in Thellungiella it was over twofold higher than [B](int) , and therefore likely to allow appreciable 1:2 boron-metabolite complexation in the shoot. This, we suggest, is an important component of Thellungiella B tolerance mechanism. © 2011 Blackwell Publishing Ltd.

  8. From trees to forest: relational complexity network and workload of air traffic controllers.

    Science.gov (United States)

    Zhang, Jingyu; Yang, Jiazhong; Wu, Changxu

    2015-01-01

    In this paper, we propose a relational complexity (RC) network framework based on RC metric and network theory to model controllers' workload in conflict detection and resolution. We suggest that, at the sector level, air traffic showing a centralised network pattern can provide cognitive benefits in visual search and resolution decision which will in turn result in lower workload. We found that the network centralisation index can account for more variance in predicting perceived workload and task completion time in both a static conflict detection task (Study 1) and a dynamic one (Study 2) in addition to other aircraft-level and pair-level factors. This finding suggests that linear combination of aircraft-level or dyad-level information may not be adequate and the global-pattern-based index is necessary. Theoretical and practical implications of using this framework to improve future workload modelling and management are discussed. We propose a RC network framework to model the workload of air traffic controllers. The effect of network centralisation was examined in both a static conflict detection task and a dynamic one. Network centralisation was predictive of perceived workload and task completion time over and above other control variables.

  9. DNA-membrane complex restoration in Micrococcus radiodurans after X-irradiation: relation to repair, DNA synthesis and DNA degradation

    Energy Technology Data Exchange (ETDEWEB)

    Dardalhon-Samsonoff, M; Averbeck, D [Institut du Radium, 75 - Paris (France). Lab. Curie

    1980-07-01

    The DNA-membrane complex in Micrococcus radiodurans was shown to be essentially constituted of proteins, lipids and DNA. The complex was dissociated immediately after X-irradiation of cells and restored during post-incubation in complete medium. In X-irradiated protoplasts some DNA remained associated with the complex. Restoration of the complex during post-incubation was only seen in a medium favouring DNA polymerase and ligase activities. Under this condition no DNA synthesis occurred, suggesting that complex restoration may involve ligase activity. The complex restoration in the wild type and the X-ray sensitive mutant UV17 of M. radiodurans was strictly dependent on the X-ray dose. It was correlated with survival and DNA degradation but always preceded the onset of DNA synthesis after X-irradiation. At the same dose the complex restoration was about 2 fold lower in mutant than in wild type cells indicating that the restoration of the complex is related to repair capacity. The results are consistent with the idea that the complex protects X-irradiated DNA of M. radiodurans from further breakdown and, subsequently, permits DNA synthesis and repair to occur.

  10. Evidence-based treatment for adult women with child abuse-related Complex PTSD: a quantitative review

    Directory of Open Access Journals (Sweden)

    Ethy Dorrepaal

    2014-10-01

    Full Text Available Introduction: Effective first-line treatments for posttraumatic stress disorder (PTSD are well established, but their generalizability to child abuse (CA-related Complex PTSD is largely unknown. Method: A quantitative review of the literature was performed, identifying seven studies, with treatments specifically targeting CA-related PTSD or Complex PTSD, which were meta-analyzed, including variables such as effect size, drop-out, recovery, and improvement rates. Results: Only six studies with one or more cognitive behavior therapy (CBT treatment conditions and one with a present centered therapy condition could be meta-analyzed. Results indicate that CA-related PTSD patients profit with large effect sizes and modest recovery and improvement rates. Treatments which include exposure showed greater effect sizes especially in completers’ analyses, although no differential results were found in recovery and improvement rates. However, results in the subgroup of CA-related Complex PTSD studies were least favorable. Within the Complex PTSD subgroup, no superior effect size was found for exposure, and affect management resulted in more favorable recovery and improvement rates and less drop-out, as compared to exposure, especially in intention-to-treat analyses. Conclusion: Limited evidence suggests that predominantly CBT treatments are effective, but do not suffice to achieve satisfactory end states, especially in Complex PTSD populations. Moreover, we propose that future research should focus on direct comparisons between types of treatment for Complex PTSD patients, thereby increasing generalizability of results.

  11. Effect of Feed Substrate Thickness on the Bandwidth and Radiation Characteristics of an Aperture-Coupled Microstrip Antenna with a High Permittivity Feed Substrate

    Directory of Open Access Journals (Sweden)

    Jae-Hyun Kim

    2018-04-01

    Full Text Available The impedance bandwidth and radiation characteristics of an aperture-coupled microstrip line-fed patch antenna (ACMPA with a high permittivity (ɛr = 10 feed substrate suitable for integration with a monolithic microwave integrated circuit (MMIC are investigated for various feed substrate thicknesses through an experiment and computer simulation. The impedance bandwidth of an ACMPA with a high permittivity feed substrate increases as the feed substrate thickness decreases. Furthermore, the front-to-back ratio of an ACMPA with a high permittivity feed substrate increases and the cross-polarization level decreases as the feed substrate thickness decreases. As the impedance bandwidth of an ACMPA with a high permittivity feed substrate increases and its radiation characteristics improve as the feed substrate thickness decreases, the ACMPA configuration becomes suitable for integration with an MMIC.

  12. Stuttering Frequency in Relation to Lexical Diversity, Syntactic Complexity, and Utterance Length

    Science.gov (United States)

    Wagovich, Stacy A.; Hall, Nancy E.

    2018-01-01

    Children's frequency of stuttering can be affected by utterance length, syntactic complexity, and lexical content of language. Using a unique small-scale within-subjects design, this study explored whether language samples that contain more stuttering have (a) longer, (b) syntactically more complex, and (c) lexically more diverse utterances than…

  13. Prediction of Protein-Protein Interactions Related to Protein Complexes Based on Protein Interaction Networks

    Directory of Open Access Journals (Sweden)

    Peng Liu

    2015-01-01

    Full Text Available A method for predicting protein-protein interactions based on detected protein complexes is proposed to repair deficient interactions derived from high-throughput biological experiments. Protein complexes are pruned and decomposed into small parts based on the adaptive k-cores method to predict protein-protein interactions associated with the complexes. The proposed method is adaptive to protein complexes with different structure, number, and size of nodes in a protein-protein interaction network. Based on different complex sets detected by various algorithms, we can obtain different prediction sets of protein-protein interactions. The reliability of the predicted interaction sets is proved by using estimations with statistical tests and direct confirmation of the biological data. In comparison with the approaches which predict the interactions based on the cliques, the overlap of the predictions is small. Similarly, the overlaps among the predicted sets of interactions derived from various complex sets are also small. Thus, every predicted set of interactions may complement and improve the quality of the original network data. Meanwhile, the predictions from the proposed method replenish protein-protein interactions associated with protein complexes using only the network topology.

  14. Relational complexity modulates activity in the prefrontal cortex during numerical inductive reasoning: an fMRI study.

    Science.gov (United States)

    Feng, Xiao; Peng, Li; Chang-Quan, Long; Yi, Lei; Hong, Li

    2014-09-01

    Most previous studies investigating relational reasoning have used visuo-spatial materials. This fMRI study aimed to determine how relational complexity affects brain activity during inductive reasoning, using numerical materials. Three numerical relational levels of the number series completion task were adopted for use: 0-relational (e.g., "23 23 23"), 1-relational ("32 30 28") and 2-relational ("12 13 15") problems. The fMRI results revealed that the bilateral dorsolateral prefrontal cortex (DLPFC) showed enhanced activity associated with relational complexity. Bilateral inferior parietal lobule (IPL) activity was greater during the 1- and 2-relational level problems than during the 0-relational level problems. In addition, the left fronto-polar cortex (FPC) showed selective activity during the 2-relational level problems. The bilateral DLPFC may be involved in the process of hypothesis generation, whereas the bilateral IPL may be sensitive to calculation demands. Moreover, the sensitivity of the left FPC to the multiple relational problems may be related to the integration of numerical relations. The present study extends our knowledge of the prefrontal activity pattern underlying numerical relational processing. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Postural complexity influences development in infants born preterm with brain injury: relating perception-action theory to 3 cases.

    Science.gov (United States)

    Dusing, Stacey C; Izzo, Theresa; Thacker, Leroy R; Galloway, James Cole

    2014-10-01

    Perception-action theory suggests a cyclical relationship between movement and perceptual information. In this case series, changes in postural complexity were used to quantify an infant's action and perception during the development of early motor behaviors. Three infants born preterm with periventricular white matter injury were included. Longitudinal changes in postural complexity (approximate entropy of the center of pressure), head control, reaching, and global development, measured with the Test of Infant Motor Performance and the Bayley Scales of Infant and Toddler Development, were assessed every 0.5 to 3 months during the first year of life. All 3 infants demonstrated altered postural complexity and developmental delays. However, the timing of the altered postural complexity and the type of delays varied among the infants. For infant 1, reduced postural complexity or limited action while learning to control her head in the midline position may have contributed to her motor delay. However, her ability to adapt her postural complexity eventually may have supported her ability to learn from her environment, as reflected in her relative cognitive strength. For infant 2, limited early postural complexity may have negatively affected his learning through action, resulting in cognitive delay. For infant 3, an increase in postural complexity above typical levels was associated with declining neurological status. Postural complexity is proposed as a measure of perception and action in the postural control system during the development of early behaviors. An optimal, intermediate level of postural complexity supports the use of a variety of postural control strategies and enhances the perception-action cycle. Either excessive or reduced postural complexity may contribute to developmental delays in infants born preterm with white matter injury. © 2014 American Physical Therapy Association.

  16. A system for traceable measurement of the microwave complex permittivity of liquids at high pressures and temperatures

    International Nuclear Information System (INIS)

    Dimitrakis, G A; Robinson, J; Kingman, S; Lester, E; George, M; Poliakoff, M; Harrison, I; Gregory, A P; Lees, K

    2009-01-01

    A system has been developed for direct traceable dielectric measurements on liquids at high pressures and temperatures. The system consists of a coaxial reflectometric sensor terminated by a metallic cylindrical cell to contain the liquid. It has been designed for measurements on supercritical liquids, but as a first step measurements on dielectric reference liquids were performed. This paper reports on a full evaluation of the system up to 2.5 GHz using methanol, ethanol and n-propanol at pressures up to 9 MPa and temperatures up to 273 °C. A comprehensive approach to the evaluation of uncertainties using Monte Carlo modelling is used

  17. Comparison of Structurally–Related Alkoxide, Amine, and Thiolate–Ligated MII (M= Fe, Co) Complexes: the Influence of Thiolates on the Properties of Biologically Relevant Metal Complexes

    Science.gov (United States)

    Brines, Lisa M.; Villar-Acevedo, Gloria; Kitagawa, Terutaka; Swartz, Rodney D.; Lugo-Mas, Priscilla; Kaminsky, Werner; Benedict, Jason B.; Kovacs, Julie A.

    2009-01-01

    Mechanistic pathways of metalloenzymes are controlled by the metal ion’s electronic and magnetic properties, which are tuned by the coordinated ligands. The functional advantage gained by incorporating cysteinates into the active site of non-heme iron enzymes such as superoxide reductase (SOR) is not entirely understood. Herein we compare the structural and redox properties of a series of structurally–related thiolate, alkoxide, and amine–ligated Fe(II) complexes in order to determine how the thiolate influences properties critical to function. Thiolates are shown to reduce metal ion Lewis acidity relative to alkoxides and amines, and have a strong trans influence thereby helping to maintain an open coordination site. Comparison of the redox potentials of the structurally analogous compounds described herein indicates that alkoxide ligands favor the higher-valent Fe3+ oxidation state, amine ligands favor the reduced Fe2+ oxidation state, and thiolates fall somewhere in between. These properties provide a functional advantange for substrate reducing enzymes in that they provide a site at the metal ion for substrate to bind, and a moderate potential that facilitates both substrate reduction, and regeneration of the catalytically active reduced state. Redox potentials for structurally–related Co(II) complexes are shown to be cathodically–shifted relative to their Fe(II) analogues, making them ineffective reducing agents for substrates such as superoxide. PMID:21731109

  18. Light harvesting complexes of Chromera velia, photosynthetic relative of apicomplexan parasites

    KAUST Repository

    Tichý , Josef; Gardian, Zdenko; Bí na, David; Koní k, Peter; Litví n, Radek V.; Herbstová , Miroslava; Pain, Arnab; Vá cha, František

    2013-01-01

    The structure and composition of the light harvesting complexes from the unicellular alga Chromera velia were studied by means of optical spectroscopy, biochemical and electron microscopy methods. Two different types of antennae systems were

  19. Decompositions of the polyhedral product functor with applications to moment-angle complexes and related spaces.

    Science.gov (United States)

    Bahri, A; Bendersky, M; Cohen, F R; Gitler, S

    2009-07-28

    This article gives a natural decomposition of the suspension of a generalized moment-angle complex or partial product space which arises as the polyhedral product functor described below. The introduction and application of the smash product moment-angle complex provides a precise identification of the stable homotopy type of the values of the polyhedral product functor. One direct consequence is an analysis of the associated cohomology. For the special case of the complements of certain subspace arrangements, the geometrical decomposition implies the homological decomposition in earlier work of others as described below. Because the splitting is geometric, an analogous homological decomposition for a generalized moment-angle complex applies for any homology theory. Implied, therefore, is a decomposition for the Stanley-Reisner ring of a finite simplicial complex, and natural generalizations.

  20. Bacterial biodiversity-ecosystem functioning relations are modified by environmental complexity.

    Science.gov (United States)

    Langenheder, Silke; Bulling, Mark T; Solan, Martin; Prosser, James I

    2010-05-26

    With the recognition that environmental change resulting from anthropogenic activities is causing a global decline in biodiversity, much attention has been devoted to understanding how changes in biodiversity may alter levels of ecosystem functioning. Although environmental complexity has long been recognised as a major driving force in evolutionary processes, it has only recently been incorporated into biodiversity-ecosystem functioning investigations. Environmental complexity is expected to strengthen the positive effect of species richness on ecosystem functioning, mainly because it leads to stronger complementarity effects, such as resource partitioning and facilitative interactions among species when the number of available resource increases. Here we implemented an experiment to test the combined effect of species richness and environmental complexity, more specifically, resource richness on ecosystem functioning over time. We show, using all possible combinations of species within a bacterial community consisting of six species, and all possible combinations of three substrates, that diversity-functioning (metabolic activity) relationships change over time from linear to saturated. This was probably caused by a combination of limited complementarity effects and negative interactions among competing species as the experiment progressed. Even though species richness and resource richness both enhanced ecosystem functioning, they did so independently from each other. Instead there were complex interactions between particular species and substrate combinations. Our study shows clearly that both species richness and environmental complexity increase ecosystem functioning. The finding that there was no direct interaction between these two factors, but that instead rather complex interactions between combinations of certain species and resources underlie positive biodiversity ecosystem functioning relationships, suggests that detailed knowledge of how individual

  1. Bacterial biodiversity-ecosystem functioning relations are modified by environmental complexity.

    Directory of Open Access Journals (Sweden)

    Silke Langenheder

    Full Text Available BACKGROUND: With the recognition that environmental change resulting from anthropogenic activities is causing a global decline in biodiversity, much attention has been devoted to understanding how changes in biodiversity may alter levels of ecosystem functioning. Although environmental complexity has long been recognised as a major driving force in evolutionary processes, it has only recently been incorporated into biodiversity-ecosystem functioning investigations. Environmental complexity is expected to strengthen the positive effect of species richness on ecosystem functioning, mainly because it leads to stronger complementarity effects, such as resource partitioning and facilitative interactions among species when the number of available resource increases. METHODOLOGY/PRINCIPAL FINDINGS: Here we implemented an experiment to test the combined effect of species richness and environmental complexity, more specifically, resource richness on ecosystem functioning over time. We show, using all possible combinations of species within a bacterial community consisting of six species, and all possible combinations of three substrates, that diversity-functioning (metabolic activity relationships change over time from linear to saturated. This was probably caused by a combination of limited complementarity effects and negative interactions among competing species as the experiment progressed. Even though species richness and resource richness both enhanced ecosystem functioning, they did so independently from each other. Instead there were complex interactions between particular species and substrate combinations. CONCLUSIONS/SIGNIFICANCE: Our study shows clearly that both species richness and environmental complexity increase ecosystem functioning. The finding that there was no direct interaction between these two factors, but that instead rather complex interactions between combinations of certain species and resources underlie positive biodiversity

  2. A Relational Ethics Framework for Advancing Practice with Children with Complex Health Care Needs and Their Parents.

    Science.gov (United States)

    Carnevale, Franco A; Teachman, Gail; Bogossian, Aline

    2017-12-01

    Children with complex health care needs are an emerging population that commonly requires long-term supportive services. A growing body of evidence has highlighted that these children and their families experience significant challenges. Many of these challenges involve ethical concerns that have been under-recognized. In this article, we (a) outline ethical concerns that arise in clinical practice with children with complex health care needs and their families (e.g.: exclusion of children's voices in discussions and decisions that affect them; difficulties in defining their best interests; clashes across the array of social roles that parents manage; limited recognition of the ethical significance of parents' and other family members' interests) and (b) propose a relational ethics framework for addressing these concerns. Our framework draws on hermeneutical interpretation and moral experience as foundational orientations, recognizing children with complex health care needs as relationally embedded agents, who while dependent and entitled to protection, are simultaneously agential. Children's and parents' interests are relationally intertwined and interdependent. Families are recognized as significant social microcosms for the cultivation and transmission of intergenerational cultural heritage, narratives, and outlooks. We describe strategies for (a) conducting a relational ethics inquiry and (b) reconciliation of identified ethical concerns through a process of rapprochement. A relational ethics framework can promote clinical practices that are ethically attuned to the complexity of this population's needs.

  3. [Voltage-Gated Potassium Channel-Complex Antibodies Associated Encephalopathy and Related Diseases].

    Science.gov (United States)

    Watanabe, Osamu

    2016-09-01

    Voltage-gated potassium channel (VGKC) complex antibodies are auto-antibodies, initially identified in acquired neuromyotonia (aNMT; Isaacs' syndrome), which cause muscle cramps and difficulty in opening the palm of the hands. Subsequently, these antibodies were found in patients presenting with aNMT along with psychosis, insomnia, and dysautonomia, collectively termed Morvan's syndrome (MoS), and in a limbic encephalopathy (LE) patient with prominent amnesia and frequent seizures. Typical LE cases have a distinctive adult-onset, frequent, brief dystonic seizure semiology that predominantly affects the arms and ipsilateral face. It has now been termed faciobrachial dystonic seizures (FBDS). The VGKC complex is a group of proteins that are strongly associated in situ and after extraction in the mild detergent digitonin. Recent studies indicated that the VGKC complex antibodies are mainly directed toward associated proteins (for example LGI1, Caspr2) that complex with VGKCs themselves. Patients with aNMT or MoS are most likely to have Caspr2 antibodies, whereas LGI1 antibodies are found characteristically in patients with FBDS and LE. We systematically identified and quantified autoantibodies in patient sera with VGKC-complex antibody associated encephalopathy and showed the relationship between individual antibodies and patient's symptoms. Furthermore, we revealed how autoantibodies disrupt the physiological functions of target proteins. LGI1 antibodies neutralize the interaction between LGI1 and ADAM22, reducing the synaptic AMPA receptors.

  4. R matrix: its relation to Titchmarsh-Weyl theory and its complex rotated analogue

    International Nuclear Information System (INIS)

    Elander, N.; Krylstedt, P.; Braendas, E.; Engdahl, E.

    1986-01-01

    The R matrix theory in its simplest form is discussed and analyzed in terms of the classical Titchmarsh-Weyl's theory for a singular second order differential equation. It is observed that the R matrix described as an abstract R operator is contained in the framework of Weyls classical extension to an infinite interval of finite Sturm-Liuoville theory. As a result they find that the exterior complex rotation method can be synthesized with the R matrix theory to obtain a method for deriving the S matrix poles out in the complex energy or momentum planes

  5. Geology and geochemistry of Massangana Granitoid Complex, Brazil, and its relation with tin mineralization

    International Nuclear Information System (INIS)

    Romanini, S.J.

    1982-01-01

    The geochemical and petroLogical characteristics of the Massangana Granitoid Complex, situated in the Rondonia Federal Territory, Brazil, aiming to discriminate the tin mineralized granitic rocks from the no mineralized ones. The collected samples consists of examples in tin mineralized and sterile phases. The elements traces were determined by x-ray fluorescence analysis, emission spectrography, molecular absorption spectrophotometry and atomic absorption spectrophotometry. The complex edifying evolved in four sucessive episodes called Massangana Phase, Bom Jardim Phase, Sao domingos Phase and Taboca Phase ordered stratigraphycally in this sequence. (author/M.C.K.) [pt

  6. The first experimental confirmation of the fractional kinetics containing the complex-power-law exponents: Dielectric measurements of polymerization reactions

    Science.gov (United States)

    Nigmatullin, R. R.; Arbuzov, A. A.; Salehli, F.; Giz, A.; Bayrak, I.; Catalgil-Giz, H.

    2007-01-01

    For the first time we achieved incontestable evidence that the real process of dielectric relaxation during the polymerization reaction of polyvinylpyrrolidone (PVP) is described in terms of the fractional kinetic equations containing complex-power-law exponents. The possibility of the existence of the fractional kinetics containing non-integer complex-power-law exponents follows from the general theory of dielectric relaxation that has been suggested recently by one of the authors (R.R.N). Based on the physical/geometrical meaning of the fractional integral with complex exponents there is a possibility to develop a general theory of dielectric relaxation based on the self-similar (fractal) character of the reduced (averaged) microprocesses that take place in the mesoscale region. This theory contains some essential predictions related to existence of the non-integer power-law kinetics and the results of this paper can be considered as the first confirmation of existence of the kinetic phenomena that are described by fractional derivatives with complex-power-law exponents. We want to stress here that with the help of a new complex fitting function for the complex permittivity it becomes possible to describe the whole process for real and imaginary parts simultaneously throughout the admissible frequency range (30 Hz-13 MHz). The fitting parameters obtained for the complex permittivity function for three temperatures (70, 90 and 110 °C) confirm in general the picture of reaction that was known qualitatively before. They also reveal some new features, which improve the interpretation of the whole polymerization process. We hope that these first results obtained in the paper will serve as a good stimulus for other researches to find the traces of the existence of new fractional kinetics in other relaxation processes unrelated to the dielectric relaxation. These results should lead to the reconsideration and generalization of irreversibility and kinetic phenomena that

  7. Coordination chemistry of gadolinium complexes having pyridine carboxylate units in relation with the medical imagery

    International Nuclear Information System (INIS)

    Gateau, C.; Chatterton, N.; Nonat, A.; Mazzanti, M.; Pecaut, J.; Borel, A.; Merbach, A.; Heim, L.

    2005-01-01

    In order to study the influence of the coordination sphere on the properties which govern the relaxivity, ligands containing pyridine carboxylates units have been particularly studied. It has been shown that the tripodal ligand tpaa forms with gadolinium (III) a neutral complex having a relaxivity (r1p=13.3 mM -1 at 298 K and 60 MHz) which is three times superior to the contrast agents currently used in NMR Imaging. To explain this remarkably relaxivity, two new ligands analogous to the tpaa: the tpatcn and the bpeda containing pyridine carboxylate units bound to one or several aliphatic nitrogen have been studied in modulating the number of coordination sites and the symmetry degree. The study of the relaxivity of the corresponding gadolinium (III) complexes gives precious data on the understanding of the results in the case of the complex [Gd(tpaa)]. The synthesis and the properties of these gadolinium (III) complexes will be presented during this conference. (O.M.)

  8. Complex regional pain syndrome related movement disorders : studies on pathophysiology and therapy.

    NARCIS (Netherlands)

    Munts, Alexander Gerard

    2011-01-01

    Complex regional pain syndrome (CRPS) may occur after trauma, usually to one limb, and is characterised by pain and disturbed blood flow, temperature regulation and motor control. Knowledge on CRPS and its movement disorders is scarce. Dysfunction in small nerve fiber processing was found in CRPS

  9. Complex regional pain syndrome related dystonia : exploratory metabolomics and therapeutic studies

    NARCIS (Netherlands)

    Plas, Anton Adriaan van der

    2013-01-01

    Dit proefschrift beschrijft de resultaten van aan aantal studies naar bewegingsstoornissen en pijn bij patiënten met complex regionaal pijnsyndroom (CRPS). Ten eerste werd het effect onderzocht van intrathecaal baclofen op verschillende pijnkwaliteiten bij CRPS-patiënten, de invloed bestudeerd van

  10. Applying the PDCA Cycle to the Complex Task of Teaching and Assessing Public Relations Writing

    Science.gov (United States)

    Knight, John E.; Allen, Sandra

    2012-01-01

    Teaching skills, knowledge and abilities appropriate for career-ready graduates and assessing learning are complex issues. Developing a valid and reliable approach is often by trial and error. Instead, the authors employed Deming's PDCA Cycle of continuous improvement as a systematic procedure to incrementally move closer to their goal. This paper…

  11. Defects in the COG complex and COG-related trafficking regulators affect neuronal Golgi function.

    Directory of Open Access Journals (Sweden)

    Leslie K Climer

    2015-10-01

    Full Text Available The Conserved Oligomeric Golgi (COG complex is an evolutionarily conserved hetero-octameric protein complex that has been proposed to organize vesicle tethering at the Golgi apparatus. Defects in seven of the eight COG subunits are linked to Congenital Disorders of Glycosylation (CDG-type II, a family of rare diseases involving misregulation of protein glycosylation, alterations in Golgi structure, variations in retrograde trafficking through the Golgi and system-wide clinical pathologies. A troublesome aspect of these diseases are the neurological pathologies such as low IQ, microcephaly and cerebellar atrophy. The essential function of the COG complex is dependent upon interactions with other components of trafficking machinery, such as Rab-GTPases and SNAREs. COG-interacting Rabs and SNAREs have been implicated in neurodegenerative diseases like Alzheimer’s disease and Parkinson’s disease. Defects in Golgi maintenance disrupts trafficking and processing of essential proteins, frequently associated with and contributing to compromised neuron function and human disease. Despite the recent advances in molecular neuroscience, the subcellular bases for most neurodegenerative diseases are poorly understood. This article gives an overview of the potential contributions of the COG complex and its Rab and SNARE partners in the pathogenesis of different neurodegenerative disorders.

  12. Regulation of the retinoblastoma protein-related p107 by G1 cyclin complexes

    NARCIS (Netherlands)

    Beijersbergen, R.L.; Carlée, L.; Kerkhoven, R.M.; Bernards, R.A.

    1995-01-01

    The orderly progression through the cell cycle is mediated by the sequential activation of several cyclin/cyclin-dependent kinase (cdk) complexes. These kinases phosphorylate a number of cellular substrates, among which is the product of the retinoblastoma gene, pRb. Phosphorylation of pRb in late

  13. The Complex Relation between Bullying, Victimization, Acceptance, and Rejection: Giving Special Attention to Status, Affection, and Sex Differences

    Science.gov (United States)

    Veenstra, Rene; Lindenberg, Siegwart; Munniksma, Anke; Dijkstra, Jan Kornelis

    2010-01-01

    To understand the complex nature of bullies' acceptance and rejection, this article considered goal-framing effects of status and affection as they relate to the gender of the bully (male vs. female bullies), the target (male vs. female victims), and the evaluator (acceptance and rejection from male vs. female classmates). The hypotheses were…

  14. Complexities in understanding the role of compensation-related factors on recovery from whiplash-associated disorders : discussion paper 2

    NARCIS (Netherlands)

    Carroll, Linda J.; Connelly, Luke B.; Spearing, Natalie M.; Cote, Pierre; Buitenhuis, Jan; Kenardy, Justin

    2011-01-01

    Study Design. Focused discussion. Objective. To present some of the complexities in conducting research on the role of compensation and compensation-related factors in recovery from whiplash-associated disorders (WAD) and to suggest directions for future research. Summary of Background Data. There

  15. On Modeling the Behavior of Comparators for Complex Fuzzy Objects in a Fuzzy Object-Relational Database Management System

    Directory of Open Access Journals (Sweden)

    JuanM. Medina

    2012-08-01

    Full Text Available This paper proposes a parameterized definition for fuzzy comparators on complex fuzzy datatypes like fuzzy collections with conjunctive semantics and fuzzy objects. This definition and its implementation on a Fuzzy Object-Relational Database Management System (FORDBMS provides the designer with a powerful tool to adapt the behavior of these operators to the semantics of the considered application.

  16. Evidence-based treatment for adult women with child abuse-related Complex PTSD: a quantitative review

    NARCIS (Netherlands)

    Dorrepaal, Ethy; Thomaes, Kathleen; Hoogendoorn, Adriaan W.; Veltman, Dick J.; Draijer, Nel; van Balkom, Anton J. L. M.

    2014-01-01

    Effective first-line treatments for posttraumatic stress disorder (PTSD) are well established, but their generalizability to child abuse (CA)-related Complex PTSD is largely unknown. A quantitative review of the literature was performed, identifying seven studies, with treatments specifically

  17. The composition-explicit distillation curve technique: Relating chemical analysis and physical properties of complex fluids.

    Science.gov (United States)

    Bruno, Thomas J; Ott, Lisa S; Lovestead, Tara M; Huber, Marcia L

    2010-04-16

    The analysis of complex fluids such as crude oils, fuels, vegetable oils and mixed waste streams poses significant challenges arising primarily from the multiplicity of components, the different properties of the components (polarity, polarizability, etc.) and matrix properties. We have recently introduced an analytical strategy that simplifies many of these analyses, and provides the added potential of linking compositional information with physical property information. This aspect can be used to facilitate equation of state development for the complex fluids. In addition to chemical characterization, the approach provides the ability to calculate thermodynamic properties for such complex heterogeneous streams. The technique is based on the advanced distillation curve (ADC) metrology, which separates a complex fluid by distillation into fractions that are sampled, and for which thermodynamically consistent temperatures are measured at atmospheric pressure. The collected sample fractions can be analyzed by any method that is appropriate. The analytical methods we have applied include gas chromatography (with flame ionization, mass spectrometric and sulfur chemiluminescence detection), thin layer chromatography, FTIR, corrosivity analysis, neutron activation analysis and cold neutron prompt gamma activation analysis. By far, the most widely used analytical technique we have used with the ADC is gas chromatography. This has enabled us to study finished fuels (gasoline, diesel fuels, aviation fuels, rocket propellants), crude oils (including a crude oil made from swine manure) and waste oils streams (used automotive and transformer oils). In this special issue of the Journal of Chromatography, specifically dedicated to extraction technologies, we describe the essential features of the advanced distillation curve metrology as an analytical strategy for complex fluids. Published by Elsevier B.V.

  18. Characterization of the permittivity of controlled porous water ice-dust mixtures to support the radar exploration of icy bodies

    Science.gov (United States)

    Brouet, Y.; Neves, L.; Sabouroux, P.; Levasseur-Regourd, A. C.; Poch, O.; Encrenaz, P.; Pommerol, A.; Thomas, N.; Kofman, W.

    2016-12-01

    The internal properties of porous and icy bodies in the solar system can be investigated by ground-penetrating radars (GPRs), like the COmet Nucleus Sounding Experiment by Radiowave Transmission instrument on board the Rosetta spacecraft which has sounded the interior of the nucleus of comet 67P/Churyumov-Gerasimenko. Accurate constraints on the permittivity of icy media are needed for the interpretation of the data. We report novel permittivity measurements performed on water ice samples and icy mixtures with porosities in the 31-91% range. The measurements have been performed between 50 MHz and 2 GHz with a coaxial cell on a total of 38 samples with a good reproducibility. We used controlled procedures to produce fine-grained and coarse-grained ice samples with a mean diameter of 4.5 μm and 67 μm, respectively, and to prepare icy mixtures. The JSC-1A lunar regolith simulant was used as the dust component in the mixtures. The results are focused on the real-part ɛ' of the permittivity, which constrains the phase velocity of the radio waves in low-loss media. The values of ɛ' show a nondispersive behavior and are within the range of 1.1 to 2.7. They decrease with the increasing porosity Φ according to E(1 - Φ), with E equal to about 3.13 for pure water ice, and in the 3.8-7.5 range for ice-dust mixtures with a dust-to-ice volumetric ratio in the 0.1-2.8 range, respectively. These measurements are also relevant for radiometers operating in the millimeter-submillimeter domains, as suggested by the nondispersive behavior of the mixtures and of the pure components.

  19. Role of viscosity in the magnetic field effect on pyrene-DMA exciplex emission at different permittivities

    Science.gov (United States)

    Jana, Amit Kumar; Roy, Partha; Nath, Deb Narayan

    2014-02-01

    Effect of viscosity variation on the magnetic field effect in pyrene-N,N-dimethylaniline exciplex luminescence has been studied at different permittivity values. The data is compatible to the model of Krissinel et al. (1999) [10] reported earlier to explain the effect probing the escape yield of radical pairs. It is shown that the data can also be explained on the basis of a simple model. It is interesting to note that the present letter also demonstrates the positive slope of MFE with diffusivity at extremely high viscous condition as predicted by Krissinel et al. (1999) [10] which has not been observed in earlier experiments.

  20. Neptunium(V) complexation by natural pyoverdins and related model compounds

    Energy Technology Data Exchange (ETDEWEB)

    Moll, H.; Glorius, M.; Bernhard, G. [Forschungszentrum Dresden-Rossendorf e.V., Inst. of Radiochemistry (Germany); Johnsson, A. [Goeteborg Univ., Microbiology, Dept. of Cell and Molecular Biology (Sweden); Univ. of Copenhagen, Dept. of Chemistry (Denmark); Schaefer, M.; Budzikiewicz, H. [Univ. zu Koeln, Inst. fuer Organische Chemie (Germany); Pedersen, K. [Goeteborg Univ., Microbiology, Dept. of Cell and Molecular Biology (Sweden)

    2010-07-01

    Ubiquitous fluorescent Pseudomonas species secrete bacterial pyoverdin-type siderophores. These bioligands have great potential to bind and transport actinides in the environment due to their hydroxamate and catechol functionalities. We investigated the unknown interaction of the neptunyl cation (NpO{sub 2}{sup +}) with pyoverdins (PYO) released by Pseudomonas fluorescens (CCUG 32456) cells and with simple hydroxamate (salicylhydroxamic acid: SHA and benzohydroxamic acid: BHA) and catechol (2,3-dihydroxynaphthalene: NAP) ligands using near-infrared (NIR) absorption spectroscopy over a wide pH range. NpO{sub 2}{sup +}-bioligand species of the M{sub x}L{sub y}H{sub z} type were identified from the spectrophotometric titrations in all four systems. The 1:1:2, 1:1:1, and 1:1:0 complexes were determined with the pyoverdins. In addition to 1:1 species, SHA, BHA, and NAP also form 1:2:0 species with NpO{sub 2}{sup +}. The stability constants of these neptunyl(V)-bioligand complexes and their individual spectroscopic properties are reported. Our findings indicate that NpO{sub 2}{sup +} has a stronger affinity to the catechol functionality of the pyoverdin molecule. The identified NpO{sub 2}{sup +}-PYO species belong to the strongest NpO{sub 2}{sup +} complexes with organic material reported so far. (orig.)

  1. The Relation between Degree and Strength in the Complex Network Derived from an Individual Stock

    Directory of Open Access Journals (Sweden)

    Zelin Zhang

    2016-01-01

    Full Text Available A method based on coarse-graining to construct a directed weighted complex network which models the transformation of the trading data of an individual stock is introduced. The degree (strength distribution of derived network follows a power-law. A moderated regression equation with interaction effects of average return and out-degree (in-degree on out-strength (in-strength is established. Moreover, we found that the differences of nodes affect the network’s structure and average return level impacts nodes’ eigenvector centrality and pagerank, significantly.

  2. Chess players' eye movements reveal rapid recognition of complex visual patterns: Evidence from a chess-related visual search task.

    Science.gov (United States)

    Sheridan, Heather; Reingold, Eyal M

    2017-03-01

    To explore the perceptual component of chess expertise, we monitored the eye movements of expert and novice chess players during a chess-related visual search task that tested anecdotal reports that a key differentiator of chess skill is the ability to visualize the complex moves of the knight piece. Specifically, chess players viewed an array of four minimized chessboards, and they rapidly searched for the target board that allowed a knight piece to reach a target square in three moves. On each trial, there was only one target board (i.e., the "Yes" board), and for the remaining "lure" boards, the knight's path was blocked on either the first move (the "Easy No" board) or the second move (i.e., "the Difficult No" board). As evidence that chess experts can rapidly differentiate complex chess-related visual patterns, the experts (but not the novices) showed longer first-fixation durations on the "Yes" board relative to the "Difficult No" board. Moreover, as hypothesized, the task strongly differentiated chess skill: Reaction times were more than four times faster for the experts relative to novices, and reaction times were correlated with within-group measures of expertise (i.e., official chess ratings, number of hours of practice). These results indicate that a key component of chess expertise is the ability to rapidly recognize complex visual patterns.

  3. Optical refractive index and static permittivity of mixed Zr-Si oxide thin films prepared by ion beam induced CVD

    Energy Technology Data Exchange (ETDEWEB)

    Ferrer, F.J. [Centro Nacional de Aceleradores, Av. Thomas A. Edison, 7, 41092 Sevilla (Spain)], E-mail: fjferrer@us.es; Frutos, F. [E.T.S. de Ingenieria Informatica, Avda. Reina Mercedes, s/n, 41012 Sevilla (Spain); Garcia-Lopez, J. [Centro Nacional de Aceleradores, Av. Thomas A. Edison, 7, 41092 Sevilla (Spain); Gonzalez-Elipe, A.R.; Yubero, F. [Insituto de Ciencia de Materiales de Sevilla, c/ Americo vespucio, no. 49, 41092 Sevilla (Spain)

    2007-12-03

    Mixed oxides Zr{sub x}Si{sub 1-x}O{sub 2} (0 < x < 1) thin films have been prepared at room temperature by decomposition of (CH{sub 3}CH{sub 2}O){sub 3}SiH and Zr[OC(CH{sub 3}){sub 3}]{sub 4} volatile precursors induced by mixtures of O{sub 2}{sup +} and Ar{sup +} ions. The films were flat and amorphous independently of the Si/Zr ratio and did not present phase segregation of the pure single oxides (SiO{sub 2} and ZrO{sub 2}). A 10-23 at.% of H and 1-5 at.% of C atoms remained incorporated in the films depending on the mixture ratio of the Si and Zr precursors and the composition of the bombarding gas used during the deposition process. These impurities are mainly forming hydroxyl and carboxylic groups. Optical refractive index and static permittivity of the films were determined by reflection NIR-Vis spectroscopy and C-V electrical characterization, respectively. It is found that the refractive index increases non-linearly from 1.45 to 2.10 as the Zr content in the thin films increases. The static permittivity also increases non-linearly from {approx} 4 for pure SiO{sub 2} to {approx} 15 for pure ZrO{sub 2}. Optical and electrical characteristics of the films are justified by their impurity content and the available theories.

  4. A Self-Oscillating System to Measure the Conductivity and the Permittivity of Liquids within a Single Triangular Signal

    Directory of Open Access Journals (Sweden)

    Sylvain Druart

    2014-01-01

    Full Text Available We present a methodology and a circuit to extract liquid resistance and capacitance simultaneously from the same output signal using interdigitated sensing electrodes. The principle consists in the generation of a current square wave and its application to the sensor to create a triangular output voltage which contains both the conductivity and permittivity parameters in a single periodic segment. This concept extends the Triangular Waveform Voltage (TWV signal generation technique and is implemented by a system which consists in a closed-loop current-controlled oscillator and only requires DC power to operate. The system interface is portable and only a small number of electrical components are used to generate the expected signal. Conductivities of saline NaCl and KCl solutions, being first calibrated by commercial equipment, are characterized by a system prototype. The results show excellent linearity and prove the repeatability of the measurements. Experiments on water-glycerol mixtures validate the proposed sensing approach to measure the permittivity and the conductivity simultaneously. We discussed and identified the sources of measurement errors as circuit parasitic capacitances, switching clock feedthrough, charge injection, bandwidth, and control-current quality.

  5. High frequency permeability and permittivity spectra of BiFeO{sub 3}/(CoTi)-BaM ferrite composites

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Yun; Wu, Xiaohan; Li, Qifan; Yu, Ting; Feng, Zekun, E-mail: fengzekun@hust.edu.cn [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); Chen, Zhongyan [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); Jiangmen Magsource New Material CO., LTD., 529000 Guangdong (China); Su, Zhijuan; Chen, Yajie; Harris, Vincent G. [Center for Microwave Magnetic Materials and Integrated Circuits, and Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States)

    2015-05-07

    Low magnetic loss ferrite composites consisting of Ba(CoTi){sub 1.2}Fe{sub 9.6}O{sub 19} and BiFeO{sub 3} (BFO) ferrite were investigated for permeability, permittivity, and high frequency losses at 10 MHz–1 GHz. The phase fraction of BiFeO{sub 3} was quantitatively analyzed by X-ray diffraction measurements. An effective medium approach was employed to predict the effective permeability and permittivity for the ferrite composites, which was found to be in good agreement with experimental data. The experiment demonstrated low magnetic losses (<0.128), modified by BFO phase fraction, while retaining high permeability (∼10.86) at 300 MHz. More importantly, the BFO phase resulted in a reduction of magnetic loss by 32%, as BFO phase increased from 2.7 vol. % to 12.6 vol. %. The effect of BFO phase on magnetic and dielectric properties revealed great potential for use in the miniaturization of high efficiency antennas.

  6. Tunable permittivity and permeability of low loss Z + Y-type ferrite composites for ultra-high frequency applications

    Energy Technology Data Exchange (ETDEWEB)

    Su, Zhijuan; Hu, Bolin; Chen, Yajie, E-mail: y.chen@neu.edu; Harris, Vincent G. [Center for Microwave Magnetic Materials and Integrated Circuits, and Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States); Li, Qifan; Feng, Zekun [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); Wang, Xian [Center for Microwave Magnetic Materials and Integrated Circuits, and Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States); School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2015-05-07

    A series of Z-type and Y-type ferrite composites with various phase fractions were studied for their RF properties including the measurement of permittivity to permeability spectra over a frequency range of 0.1–10 GHz. Phase identification of the ferrite composites' constituents was determined by X-ray diffraction. An effective medium approximation was used to predict the magnetic and dielectric behavior of the composites. The experiments indicated that the composite having 75 vol. % of Z-type ferrite demonstrated a permeability of ∼12 with a nearly equivalent permittivity, yielding a ratio (μ′/ε′) of 0.91 at a frequency range from 0.55 to 0.75 GHz. The dielectric loss (i.e., tan δ{sub ε}) and magnetic loss (i.e., tan δ{sub μ}) were measured to be lower than 0.08 at f = 0.1–1 GHz and 0.29 at f = 0.1–0.7 GHz, respectively. Furthermore, the loss factors, as tan δ{sub ε}/ε′ and tan δ{sub μ}/μ′, were calculated to be 0.003 and 0.02 at 0.65 GHz, respectively.

  7. Passive radiofrequency shimming in the thighs at 3 Tesla using high permittivity materials and body coil receive uniformity correction.

    Science.gov (United States)

    Brink, Wyger M; Versluis, Maarten J; Peeters, Johannes M; Börnert, Peter; Webb, Andrew G

    2016-12-01

    To explore the effects of high permittivity dielectric pads on the transmit and receive characteristics of a 3 Tesla body coil centered at the thighs, and their implications on image uniformity in receive array applications. Transmit and receive profiles of the body coil with and without dielectric pads were simulated and measured in healthy volunteers. Parallel imaging was performed using sensitivity encoding (SENSE) with and without pads. An intensity correction filter was constructed from the measured receive profile of the body coil. Measured and simulated data show that the dielectric pads improve the transmit homogeneity of the body coil in the thighs, but decrease its receive homogeneity, which propagates into reconstruction algorithms in which the body coil is used as a reference. However, by correcting for the body coil reception profile this effect can be mitigated. Combining high permittivity dielectric pads with an appropriate body coil receive sensitivity filter improves the image uniformity substantially compared with the situation without pads. Magn Reson Med 76:1951-1956, 2016. © 2015 International Society for Magnetic Resonance in Medicine. © 2015 International Society for Magnetic Resonance in Medicine.

  8. How Unstable Are Complex Financial Systems? Analyzing an Inter-bank Network of Credit Relations

    Science.gov (United States)

    Sinha, Sitabhra; Thess, Maximilian; Markose, Sheri

    The recent worldwide economic crisis of 2007-09 has focused attention on the need to analyze systemic risk in complex financial networks. We investigate the problem of robustness of such systems in the context of the general theory of dynamical stability in complex networks and, in particular, how the topology of connections influence the risk of the failure of a single institution triggering a cascade of successive collapses propagating through the network. We use data on bilateral liabilities (or exposure) in the derivatives market between 202 financial intermediaries based in USA and Europe in the last quarter of 2009 to empirically investigate the network structure of the over-the-counter (OTC) derivatives market. We observe that the network exhibits both heterogeneity in node properties and the existence of communities. It also has a prominent core-periphery organization and can resist large-scale collapse when subjected to individual bank defaults (however, failure of any bank in the core may result in localized collapse of the innermost core with substantial loss of capital) but is vulnerable to system-wide breakdown as a result of an accompanying liquidity crisis.

  9. Mixed-method research protocol: defining and operationalizing patient-related complexity of nursing care in acute care hospitals.

    Science.gov (United States)

    Huber, Evelyn; Kleinknecht-Dolf, Michael; Müller, Marianne; Kugler, Christiane; Spirig, Rebecca

    2017-06-01

    To define the concept of patient-related complexity of nursing care in acute care hospitals and to operationalize it in a questionnaire. The concept of patient-related complexity of nursing care in acute care hospitals has not been conclusively defined in the literature. The operationalization in a corresponding questionnaire is necessary, given the increased significance of the topic, due to shortened lengths of stay and increased patient morbidity. Hybrid model of concept development and embedded mixed-methods design. The theoretical phase of the hybrid model involved a literature review and the development of a working definition. In the fieldwork phase of 2015 and 2016, an embedded mixed-methods design was applied with complexity assessments of all patients at five Swiss hospitals using our newly operationalized questionnaire 'Complexity of Nursing Care' over 1 month. These data will be analysed with structural equation modelling. Twelve qualitative case studies will be embedded. They will be analysed using a structured process of constructing case studies and content analysis. In the final analytic phase, the quantitative and qualitative data will be merged and added to the results of the theoretical phase for a common interpretation. Cantonal Ethics Committee Zurich judged the research programme as unproblematic in December 2014 and May 2015. Following the phases of the hybrid model and using an embedded mixed-methods design can reach an in-depth understanding of patient-related complexity of nursing care in acute care hospitals, a final version of the questionnaire and an acknowledged definition of the concept. © 2016 John Wiley & Sons Ltd.

  10. The Complexity of the Business Network Context and Its Effect on Subsidiary Relational (Over-) Embeddedness

    DEFF Research Database (Denmark)

    Nell, Phillip Christopher; Andersson, Ulf

    Many studies have focused on the effects of MNC subsidiaries’ external relational embeddedness. Little attention has been given to its antecedents and especially to the potential effect that the business network context might have. We try to fill this gap and attempt to explain variation among...... subsidiaries’ degree of relational embeddedness. Our results show a strong and robust effect of the business network context -- i.e. the network context in which the direct business relationships between the subsidiary and its partners are embedded -- on the degree of relational embeddedness. However, contrary...

  11. The Complexity of the Business Network Context and Its Effect on Subsidiary Relational (Over-) Embeddedness

    DEFF Research Database (Denmark)

    Nell, Phillip Christopher; Andersson, Ulf

    2012-01-01

    Many studies have focused on the effects of MNC subsidiaries’ external relational embeddedness. Little attention has been given to its antecedents and especially to the potential effect that the business network context might have. We try to fill this gap and attempt to explain variation among...... subsidiaries’ degree of relational embeddedness. Our results show a strong and robust effect of the business network context – i.e. the network context in which the direct business relationships between the subsidiary and its partners are embedded – on the degree of relational embeddedness. However, contrary...

  12. Servitizing manufacturers: The impact of service complexity and contractual and relational capabilities

    DEFF Research Database (Denmark)

    Kreye, Melanie; Roehrich, Jens K.; Lewis, Michael A.

    2015-01-01

    Processes of servitization will lead providers to change their service delivery structures but they also need to transform broader organisational attributes including contractual and relational capabilities. Based on case studies in the European healthcare sector, we investigate the influence...

  13. The Complexity of Neighbourhood Relations in a Multiethnic Social Housing Project in Copenhagen

    DEFF Research Database (Denmark)

    Jensen, Tina Gudrun

    2016-01-01

    This article examines the nature of coexistence in a multiethnic social housing project in Copenhagen, focusing on neighbourhood relations between majority Danes and ethnic minorities. Despite the general assumption that ethnic majorities and minorities have no neighbourhood relations, this case...... study reveals multifarious ways of relationship-making. Whereas the residents tended to emphasise separation between ethnic groups, their everyday practices indicated coexistence. These contrasts reflect the residents’ affirmations and contestations of the public national discourse about immigration...

  14. Heterogeneity of Purkinje cell simple spike-complex spike interactions: zebrin- and non-zebrin-related variations.

    Science.gov (United States)

    Tang, Tianyu; Xiao, Jianqiang; Suh, Colleen Y; Burroughs, Amelia; Cerminara, Nadia L; Jia, Linjia; Marshall, Sarah P; Wise, Andrew K; Apps, Richard; Sugihara, Izumi; Lang, Eric J

    2017-08-01

    Cerebellar Purkinje cells (PCs) generate two types of action potentials, simple and complex spikes. Although they are generated by distinct mechanisms, interactions between the two spike types exist. Zebrin staining produces alternating positive and negative stripes of PCs across most of the cerebellar cortex. Thus, here we compared simple spike-complex spike interactions both within and across zebrin populations. Simple spike activity undergoes a complex modulation preceding and following a complex spike. The amplitudes of the pre- and post-complex spike modulation phases were correlated across PCs. On average, the modulation was larger for PCs in zebrin positive regions. Correlations between aspects of the complex spike waveform and simple spike activity were found, some of which varied between zebrin positive and negative PCs. The implications of the results are discussed with regard to hypotheses that complex spikes are triggered by rises in simple spike activity for either motor learning or homeostatic functions. Purkinje cells (PCs) generate two types of action potentials, called simple and complex spikes (SSs and CSs). We first investigated the CS-associated modulation of SS activity and its relationship to the zebrin status of the PC. The modulation pattern consisted of a pre-CS rise in SS activity, and then, following the CS, a pause, a rebound, and finally a late inhibition of SS activity for both zebrin positive (Z+) and negative (Z-) cells, though the amplitudes of the phases were larger in Z+ cells. Moreover, the amplitudes of the pre-CS rise with the late inhibitory phase of the modulation were correlated across PCs. In contrast, correlations between modulation phases across CSs of individual PCs were generally weak. Next, the relationship between CS spikelets and SS activity was investigated. The number of spikelets/CS correlated with the average SS firing rate only for Z+ cells. In contrast, correlations across CSs between spikelet numbers and the

  15. Activation of CO{sub 2} and related small molecules by neopentyl-derivatized uranium complexes

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Anna-Corina

    2015-06-18

    This work reports the newly synthesized neopentyl derivatized tris(aryloxide) U{sup III} complex [(({sup nP,Me}ArO){sub 3}tacn)U{sup III}] (1) and its reactivity with small molecules like nitrous oxide (N{sub 2}O), carbon dioxide (CO{sub 2}), and sulfur dioxide (SO{sub 2}). Additionally, a deeper insight into covalency of U-R bonds with R = O, N and the participation of the f-orbitals to bonding are discussed. For this purpose, a large number of characterization methods were used, such as X-ray diffraction analysis, U{sup V}/vis/NIR, IR vibrational, Raman, X-ray absorption, EPR, and {sup 1}H, {sup 15}N, {sup 13}C and {sup 19}F NMR spectroscopy, cyclic voltammetry, SQUID magnetization measurements and DFT calculations. Moreover, all compounds were checked for purity by elemental analysis.

  16. An examination of relations between participation, communication and age in children with complex communication needs.

    Science.gov (United States)

    Clarke, Michael; Newton, Caroline; Petrides, Konstantinos; Griffiths, Tom; Lysley, Andrew; Price, Katie

    2012-03-01

    The aim of this study was to examine variation in the frequency of children's participation in out-of-school activities as a function of speech intelligibility, perceived effectiveness of the child's communication aid, and age. Sixty-nine caregivers of children with complex communication needs provided with communication aids completed a questionnaire survey. Rate of participation was higher for younger than for older children, particularly in recreational activities. Younger children with partial intelligibility participated more frequently in recreational and social activities than both younger children without speech and older children. Results and limitations are discussed within the context of participation research in childhood disability, highlighting the impact of communicative resources and maturation on everyday participation.

  17. Complex genetics of familial exudative vitreoretinopathy and related pediatric retinal detachments

    Science.gov (United States)

    Kondo, Hiroyuki

    2015-01-01

    Familial exudative vitreoretinopathy (FEVR) is a hereditary vitreoretinal disorder that can cause various types of retinal detachments. The abnormalities in eyes with FEVR are caused by poor vascularization in the peripheral retina. The genetics of FEVR is highly heterogeneous, and mutations in the genes for Wnt signaling and a transcription factor have been reported to be responsible for FEVR. These factors have been shown to be the regulators of the pathophysiological pathways of retinal vascular development. Studies conducted to identify the causative genes of FEVR have uncovered a diverse and complex relationship between FEVR and other diseases; for example, Norrie disease, a Mendelian-inherited disease; retinopathy of prematurity, a multifactorial genetic disease; and Coats disease, a nongenetic disease, associated with pediatric retinal detachments. PMID:29018668

  18. Portal vein blood flow is related to characteristics of the migrating motor complex of the gastrointestinal tract

    DEFF Research Database (Denmark)

    Qvist, Niels; Rafaelsen, Søren Rafael; Troensegaard, P.

    1994-01-01

    Objective: To measure variation in portal blood flow during the interdigestive state in relation to the migrating motor complex (MMC) in healthy volunteers. Design: Portal blood flow was measured by a duplex and colour Doppler technique with 5-min intervals during an entire MMC cycle. Total....... Conclusion: Blood flow in the portal vein varies with the characteristics of the MMC, a relationship which must be considered in future studies in health and disease....

  19. Creation of near-infrared emitting optical center related to nickel–silicon impurity complex in nanodiamond grains

    International Nuclear Information System (INIS)

    Tóth, S.; Himics, L.; Koós, M.

    2016-01-01

    Nanodiamond grains having intensive light emission in the near-infrared region even at room temperature carry an important application potential. Advantages of light emitting optical centers formed in nanodiamond grains are the emission concentrated into a narrow band and that they are mostly single photon emitter. Transition metal related impurity centers formed in nanodiamond grains exhibit these favorable properties. In this work we report on the creation of Ni–Si impurity related complex defect center in nanodiamond grains under microwave plasma assisted chemical vapor deposition (MW CVD) growth process. This complex center accounts for the previously undocumented fluorescence system with zero phonon line (ZPL) emission at 865 nm (1.433 eV) and band width of 1.5 nm (2.4 meV) at room temperature. By varying deposition conditions the Ni–Si impurity related complex defect center was formed in nanodiamond grains of 80–200 nm average sizes. Some variation of ZPL peak position and line width have been detected in nanodiamond grains prepared at different conditions, as well as in numerous nanodiamond grains prepared at the same conditions. The variations of local stress field may explain the spread of ZPL spectral parameters.

  20. The acid-labile subunit of the ternary insulin-like growth factor complex in cirrhosis: relation to liver dysfunction

    DEFF Research Database (Denmark)

    Møller, S; Juul, A; Becker, U

    2000-01-01

    BACKGROUND/AIMS: In the circulation, insulin-like growth factor-I (IGF-I) is bound in a trimeric complex of 150 kDa with IGF binding protein-3 (IGFBP-3) and the acid-labile subunit (ALS). Whereas circulating IGF-I and IGFBP-3 are reported to be low in patients with chronic liver failure, the leve...... with significant relations to liver dysfunction and other components of the IGF complex. A small hepatic extraction was found in controls, which suggests extrahepatic production of ALS. Future studies should focus on organ-specific removal of ALS.......BACKGROUND/AIMS: In the circulation, insulin-like growth factor-I (IGF-I) is bound in a trimeric complex of 150 kDa with IGF binding protein-3 (IGFBP-3) and the acid-labile subunit (ALS). Whereas circulating IGF-I and IGFBP-3 are reported to be low in patients with chronic liver failure, the level...... of ALS has not been described in relation to hepatic dysfunction. The aim of the present study was therefore to measure circulating and hepatic venous concentrations of ALS in relation to hepatic function and the IGF axis. METHODS: Twenty-five patients with cirrhosis (Child class A/B/C:5/10/10) and 30...

  1. Aberrant Functional Connectivity of the Amygdala Complexes in PTSD during Conscious and Subconscious Processing of Trauma-Related Stimuli.

    Directory of Open Access Journals (Sweden)

    Daniela Rabellino

    Full Text Available Post-traumatic stress disorder (PTSD is characterized by altered functional connectivity of the amygdala complexes at rest. However, amygdala complex connectivity during conscious and subconscious threat processing remains to be elucidated. Here, we investigate specific connectivity of the centromedial amygdala (CMA and basolateral amygdala (BLA during conscious and subconscious processing of trauma-related words among individuals with PTSD (n = 26 as compared to non-trauma-exposed controls (n = 20. Psycho-physiological interaction analyses were performed using the right and left amygdala complexes as regions of interest during conscious and subconscious trauma word processing. These analyses revealed a differential, context-dependent responses by each amygdala seed during trauma processing in PTSD. Specifically, relative to controls, during subconscious processing, individuals with PTSD demonstrated increased connectivity of the CMA with the superior frontal gyrus, accompanied by a pattern of decreased connectivity between the BLA and the superior colliculus. During conscious processing, relative to controls, individuals with PTSD showed increased connectivity between the CMA and the pulvinar. These findings demonstrate alterations in amygdala subregion functional connectivity in PTSD and highlight the disruption of the innate alarm network during both conscious and subconscious trauma processing in this disorder.

  2. Creation of near-infrared emitting optical center related to nickel–silicon impurity complex in nanodiamond grains

    Energy Technology Data Exchange (ETDEWEB)

    Tóth, S., E-mail: toth.sara@wigner.mta.hu; Himics, L.; Koós, M.

    2016-08-15

    Nanodiamond grains having intensive light emission in the near-infrared region even at room temperature carry an important application potential. Advantages of light emitting optical centers formed in nanodiamond grains are the emission concentrated into a narrow band and that they are mostly single photon emitter. Transition metal related impurity centers formed in nanodiamond grains exhibit these favorable properties. In this work we report on the creation of Ni–Si impurity related complex defect center in nanodiamond grains under microwave plasma assisted chemical vapor deposition (MW CVD) growth process. This complex center accounts for the previously undocumented fluorescence system with zero phonon line (ZPL) emission at 865 nm (1.433 eV) and band width of 1.5 nm (2.4 meV) at room temperature. By varying deposition conditions the Ni–Si impurity related complex defect center was formed in nanodiamond grains of 80–200 nm average sizes. Some variation of ZPL peak position and line width have been detected in nanodiamond grains prepared at different conditions, as well as in numerous nanodiamond grains prepared at the same conditions. The variations of local stress field may explain the spread of ZPL spectral parameters.

  3. Alkali Metal Ion Complexes with Phosphates, Nucleotides, Amino Acids, and Related Ligands of Biological Relevance. Their Properties in Solution.

    Science.gov (United States)

    Crea, Francesco; De Stefano, Concetta; Foti, Claudia; Lando, Gabriele; Milea, Demetrio; Sammartano, Silvio

    2016-01-01

    Alkali metal ions play very important roles in all biological systems, some of them are essential for life. Their concentration depends on several physiological factors and is very variable. For example, sodium concentrations in human fluids vary from quite low (e.g., 8.2 mmol dm(-3) in mature maternal milk) to high values (0.14 mol dm(-3) in blood plasma). While many data on the concentration of Na(+) and K(+) in various fluids are available, the information on other alkali metal cations is scarce. Since many vital functions depend on the network of interactions occurring in various biofluids, this chapter reviews their complex formation with phosphates, nucleotides, amino acids, and related ligands of biological relevance. Literature data on this topic are quite rare if compared to other cations. Generally, the stability of alkali metal ion complexes of organic and inorganic ligands is rather low (usually log K  Na(+) > K(+) > Rb(+) > Cs(+). For example, for citrate it is: log K ML = 0.88, 0.80, 0.48, 0.38, and 0.13 at 25 °C and infinite dilution. Some considerations are made on the main aspects related to the difficulties in the determination of weak complexes. The importance of the alkali metal ion complexes was also studied in the light of modelling natural fluids and in the use of these cations as probes for different processes. Some empirical relationships are proposed for the dependence of the stability constants of Na(+) complexes on the ligand charge, as well as for correlations among log K values of NaL, KL or LiL species (L = generic ligand).

  4. Relative utilization of fatty acids for synthesis of ketone bodies and complex lipids in the liver of developing rats.

    Science.gov (United States)

    Yeh, Y Y; Streuli, V L; Zee, P

    1977-04-01

    The regulation of hepatic ketogenesis, as related to the metabolism of fatty acids through oxidative and synthetic pathways, was studied in developing rats. [1-14C] palmitate was used as a substrate to determine the proportions of free fatty acids utilized for the production of ketone bodies, CO2 and complex lipids. Similar developmental patterns of hepatic ketogenesis were obtained by measuring the production of either [14C] acetoacetate from exogenous [1-14C] palmitate or the sum of unlabeled acetoacetate and beta-hydroxybutyrate from endogenous fatty acids. The production of total ketone bodies was low during the late fetal stage and at birth, but increased rapidly to a miximum value within 24 hr after brith. The maximal ketogenic capacity appeared to be maintained for the first 10 days of life. 14CO2 production from [1-14C] palmitate increased by two- to fourfold during the suckling period, from its initial low rate seen at birth. The capacity for synthesis of total complex lipids was low at birth and had increased by day 3 to a maximal value, which was comparable to that of adult fed rats. The high lipogenic capacity lasted throughout the remaining suckling period. When ketogenesis was inhibited by 4-pentenoic acid, the rate of synthesis of complex lipids did not increase despite an increase in unutilized fatty acids. During the mid-suckling period, approximately equal amounts of [1-14C] palmitate were utilized for the synthesis of ketone plus CO2 and for complex lipid synthesis. By contrast, in adult fed rats, the incorporation of fatty acids into complex lipids was four times higher than that of ketone plus CO2. These observations suggest that stimulated hepatic ketogenesis in suckling rats results from the rapid oxidation of fatty acids and consequent increased production of acetyl CoA, but not from impaired capacity for synthesis of complex lipids.

  5. Risk of AIDS related complex and AIDS in homosexual men with persistent HIV antigenaemia

    NARCIS (Netherlands)

    de Wolf, F.; Goudsmit, J.; Paul, D. A.; Lange, J. M.; Hooijkaas, C.; Schellekens, P.; Coutinho, R. A.; van der Noordaa, J.

    1987-01-01

    One hundred and ninety eight men seropositive for human immunodeficiency virus (HIV) antibody and 58 HIV antibody seroconverters were studied for an average of 19.3 (SEM 0.5) months to assess the relation between HIV antigenaemia and the risk of developing the acquired immune deficiency syndrome

  6. The Complex Relations between the Academy and Industry: Views from the Literature.

    Science.gov (United States)

    Anderson, Melissa S.

    2001-01-01

    This report on university-industry relations and their effects on higher education is based on three recently published books: Slaughter and Leslie's "Academic Capitalism"; Etzkowitz, Webster, and Healey's "Capitalizing Knowledge"; and Tudiver's "Universities for Sale." It reviews the implications of fundamental changes in the nature of…

  7. The complex dispersion relation of surface plasmon polaritons at gold/para-hexaphenylene interfaces

    DEFF Research Database (Denmark)

    Lemke, Christoph; Leißner, Till; Klick, Alwin

    2014-01-01

    Two-photon photoemission electron microscopy (2P-PEEM) is used to measure the real and imaginary part of the dispersion relation of surface plasmon polaritons at different interface systems. A comparison of calculated and measured dispersion data for a gold/vacuum interface demonstrates...

  8. New Media, New Voices: A Complex School Public Relations and Human Resources Challenge

    Science.gov (United States)

    Peck, Craig M.; Mullen, Carol A.

    2008-01-01

    An unprecedented increase in students' personal technology use presents a new area for study within the educational leadership and administration field. Cellular phones, video posting websites, and online social networking destinations empower students to create and distribute school-related images and stories. Student-developed media content can…

  9. Embracing Complexity: Rethinking the Relation between Play and Learning--Comment on Lillard et al. (2013)

    Science.gov (United States)

    Weisberg, Deena Skolnick; Hirsh-Pasek, Kathy; Golinkoff, Roberta Michnick

    2013-01-01

    Lillard et al. (2013) concluded that pretend play is not causally related to child outcomes and charged that the field is subject to a "play ethos", whereby research is tainted by a bias to find positive effects of play on child development. In this commentary, we embrace their call for a more solidly scientific approach to questions in this…

  10. Complex within a Complex: Integrative Taxonomy Reveals Hidden Diversity in Cicadetta brevipennis (Hemiptera: Cicadidae) and Unexpected Relationships with a Song Divergent Relative

    Science.gov (United States)

    Hertach, Thomas; Puissant, Stéphane; Gogala, Matija; Trilar, Tomi; Hagmann, Reto; Baur, Hannes; Kunz, Gernot; Wade, Elizabeth J.; Loader, Simon P.; Simon, Chris; Nagel, Peter

    2016-01-01

    Multiple sources of data in combination are essential for species delimitation and classification of difficult taxonomic groups. Here we investigate a cicada taxon with unusual cryptic diversity and we attempt to resolve seemingly contradictory data sets. Cicada songs act as species-specific premating barriers and have been used extensively to reveal hidden taxonomic diversity in morphologically similar species. The Palaearctic Cicadetta montana species complex is an excellent example where distinct song patterns have disclosed multiple recently described species. Indeed, two taxa turned out to be especially diverse in that they form a “complex within the complex”: the Cicadetta cerdaniensis song group (four species studied previously) and Cicadetta brevipennis (examined in details here). Based on acoustic, morphological, molecular, ecological and spatial data sampled throughout their broad European distribution, we find that Cicadetta brevipennis s. l. comprises five lineages. The most distinct lineage is identified as Cicadetta petryi Schumacher, 1924, which we re-assign to the species level. Cicadetta brevipennis litoralis Puissant & Hertach ssp. n. and Cicadetta brevipennis hippolaidica Hertach ssp. n. are new to science. The latter hybridizes with Cicadetta brevipennis brevipennis Fieber, 1876 at a zone inferred from intermediate song patterns. The fifth lineage requires additional investigation. The C. cerdaniensis and the C. brevipennis song groups exhibit characteristic, clearly distinct basic song patterns that act as reproductive barriers. However, they remain completely intermixed in the Bayesian and maximum likelihood COI and COII mitochondrial DNA phylogenies. The closest relative of each of the four cerdaniensis group species is a brevipennis group taxon. In our favoured scenario the phylogenetic pairs originated in common Pleistocene glacial refuges where the taxa speciated and experienced sporadic inter-group hybridization leading to extensive

  11. On the Amortized Complexity of Zero Knowledge Protocols for Multiplicative Relations

    DEFF Research Database (Denmark)

    Cramer, Ronald; Damgård, Ivan Bjerre; Pastro, Valerio

    2012-01-01

    We present a protocol that allows to prove in zero-knowledge that committed values xi, yi, zi, i = 1,…,l satisfy xiyi = zi, where the values are taken from a finite field. For error probability 2− u the size of the proof is linear in u and only logarithmic in l. Therefore, for any fixed error...... theoretically secure. Using this type of commitments we obtain, in the preprocessing model, a perfect zero-knowledge interactive proof for circuit satisfiability of circuit C where the proof has size O(|C|). We then generalize our basic scheme to a protocol that verifies l instances of an algebraic circuit D...... over K with v inputs, in the following sense: given committed values xi,j and zi, with i = 1,…,l and j = 1,…,v, the prover shows that D(xi,1,…,xi,v) = zi for i = 1,…,l. The interesting property is that the amortized complexity of verifying one circuit only depends on the multiplicative depth...

  12. Complex Inflammation mRNA-Related Response in ALS Is Region Dependent

    Directory of Open Access Journals (Sweden)

    Sara Berjaoui

    2015-01-01

    Full Text Available Inflammatory changes are analyzed in the anterior spinal cord and frontal cortex area 8 in typical spinal-predominant ALS cases. Increased numbers of astrocytes and activated microglia are found in the anterior horn of the spinal cord and pyramidal tracts. Significant increased expression of TLR7, CTSS, and CTSC mRNA and a trend to increased expression of IL10RA, TGFB1, and TGFB2 are found in the anterior lumbar spinal cord in ALS cases compared to control cases, whereas C1QTNF7 and TNFRSF1A mRNA expression levels are significantly decreased. IL6 is significantly upregulated and IL1B shows a nonsignificant increased expression in frontal cortex area 8 in ALS cases. IL-6 immunoreactivity is found in scattered monocyte-derived macrophages/microglia and TNF-α in a few cells of unknown origin in ALS cases. Increased expression and abnormal distribution of IL-1β occurred in motor neurons of the lumbar spinal cord in ALS. Strong IL-10 immunoreactivity colocalizes with TDP-43-positive inclusions in motor neurons in ALS cases. The present observations show a complex participation of cytokines and mediators of the inflammatory response in ALS consistent with increased proinflammatory cytokines and sequestration of anti-inflammatory IL-10 in affected neurons.

  13. Formation, clearance, deposition, pathogenicity, and identification of biopharmaceutical-related immune complexes: review and case studies.

    Science.gov (United States)

    Rojko, Jennifer L; Evans, Mark G; Price, Shari A; Han, Bora; Waine, Gary; DeWitte, Mark; Haynes, Jill; Freimark, Bruce; Martin, Pauline; Raymond, James T; Evering, Winston; Rebelatto, Marlon C; Schenck, Emanuel; Horvath, Christopher

    2014-06-01

    Vascular inflammation, infusion reactions, glomerulopathies, and other potentially adverse effects may be observed in laboratory animals, including monkeys, on toxicity studies of therapeutic monoclonal antibodies and recombinant human protein drugs. Histopathologic and immunohistochemical (IHC) evaluation suggests these effects may be mediated by deposition of immune complexes (ICs) containing the drug, endogenous immunoglobulin, and/or complement components in the affected tissues. ICs may be observed in glomerulus, blood vessels, synovium, lung, liver, skin, eye, choroid plexus, or other tissues or bound to neutrophils, monocytes/macrophages, or platelets. IC deposition may activate complement, kinin, and/or coagulation/fibrinolytic pathways and result in a systemic proinflammatory response. IC clearance is biphasic in humans and monkeys (first from plasma to liver and/or spleen, second from liver or spleen). IC deposition/clearance is affected by IC composition, immunomodulation, and/or complement activation. Case studies are presented from toxicity study monkeys or rats and indicate IHC-IC deposition patterns similar to those predicted by experimental studies of IC-mediated reactions to heterologous protein administration to monkeys and other species. The IHC-staining patterns are consistent with findings associated with generalized and localized IC-associated pathology in humans. However, manifestations of immunogenicity in preclinical species are generally not considered predictive to humans. © 2014 by The Author(s).

  14. Comparative Visual Analysis of Structure-Performance Relations in Complex Bulk-Heterojunction Morphologies

    KAUST Repository

    Aboulhassan, A.

    2017-07-04

    The structure of Bulk-Heterojunction (BHJ) materials, the main component of organic photovoltaic solar cells, is very complex, and the relationship between structure and performance is still largely an open question. Overall, there is a wide spectrum of fabrication configurations resulting in different BHJ morphologies and correspondingly different performances. Current state-of-the-art methods for assessing the performance of BHJ morphologies are either based on global quantification of morphological features or simply on visual inspection of the morphology based on experimental imaging. This makes finding optimal BHJ structures very challenging. Moreover, finding the optimal fabrication parameters to get an optimal structure is still an open question. In this paper, we propose a visual analysis framework to help answer these questions through comparative visualization and parameter space exploration for local morphology features. With our approach, we enable scientists to explore multivariate correlations between local features and performance indicators of BHJ morphologies. Our framework is built on shape-based clustering of local cubical regions of the morphology that we call patches. This enables correlating the features of clusters with intuition-based performance indicators computed from geometrical and topological features of charge paths.

  15. Comparative Visual Analysis of Structure-Performance Relations in Complex Bulk-Heterojunction Morphologies

    KAUST Repository

    Aboulhassan, A.; Sicat, R.; Baum, D.; Wodo, O.; Hadwiger, Markus

    2017-01-01

    The structure of Bulk-Heterojunction (BHJ) materials, the main component of organic photovoltaic solar cells, is very complex, and the relationship between structure and performance is still largely an open question. Overall, there is a wide spectrum of fabrication configurations resulting in different BHJ morphologies and correspondingly different performances. Current state-of-the-art methods for assessing the performance of BHJ morphologies are either based on global quantification of morphological features or simply on visual inspection of the morphology based on experimental imaging. This makes finding optimal BHJ structures very challenging. Moreover, finding the optimal fabrication parameters to get an optimal structure is still an open question. In this paper, we propose a visual analysis framework to help answer these questions through comparative visualization and parameter space exploration for local morphology features. With our approach, we enable scientists to explore multivariate correlations between local features and performance indicators of BHJ morphologies. Our framework is built on shape-based clustering of local cubical regions of the morphology that we call patches. This enables correlating the features of clusters with intuition-based performance indicators computed from geometrical and topological features of charge paths.

  16. Disrupting neural activity related to awake-state sharp wave-ripple complexes prevents hippocampal learning.

    Science.gov (United States)

    Nokia, Miriam S; Mikkonen, Jarno E; Penttonen, Markku; Wikgren, Jan

    2012-01-01

    Oscillations in hippocampal local-field potentials (LFPs) reflect the crucial involvement of the hippocampus in memory trace formation: theta (4-8 Hz) oscillations and ripples (~200 Hz) occurring during sharp waves are thought to mediate encoding and consolidation, respectively. During sharp wave-ripple complexes (SPW-Rs), hippocampal cell firing closely follows the pattern that took place during the initial experience, most likely reflecting replay of that event. Disrupting hippocampal ripples using electrical stimulation either during training in awake animals or during sleep after training retards spatial learning. Here, adult rabbits were trained in trace eyeblink conditioning, a hippocampus-dependent associative learning task. A bright light was presented to the animals during the inter-trial interval (ITI), when awake, either during SPW-Rs or irrespective of their neural state. Learning was particularly poor when the light was presented following SPW-Rs. While the light did not disrupt the ripple itself, it elicited a theta-band oscillation, a state that does not usually coincide with SPW-Rs. Thus, it seems that consolidation depends on neuronal activity within and beyond the hippocampus taking place immediately after, but by no means limited to, hippocampal SPW-Rs.

  17. EMG-Torque Relation in Chronic Stroke: A Novel EMG Complexity Representation With a Linear Electrode Array.

    Science.gov (United States)

    Zhang, Xu; Wang, Dongqing; Yu, Zaiyang; Chen, Xiang; Li, Sheng; Zhou, Ping

    2017-11-01

    This study examines the electromyogram (EMG)-torque relation for chronic stroke survivors using a novel EMG complexity representation. Ten stroke subjects performed a series of submaximal isometric elbow flexion tasks using their affected and contralateral arms, respectively, while a 20-channel linear electrode array was used to record surface EMG from the biceps brachii muscles. The sample entropy (SampEn) of surface EMG signals was calculated with both global and local tolerance schemes. A regression analysis was performed between SampEn of each channel's surface EMG and elbow flexion torque. It was found that a linear regression can be used to well describe the relation between surface EMG SampEn and the torque. Each channel's root mean square (RMS) amplitude of surface EMG signal in the different torque level was computed to determine the channel with the highest EMG amplitude. The slope of the regression (observed from the channel with the highest EMG amplitude) was smaller on the impaired side than on the nonimpaired side in 8 of the 10 subjects, regardless of the tolerance scheme (global or local) and the range of torques (full or matched range) used for comparison. The surface EMG signals from the channels above the estimated muscle innervation zones demonstrated significantly lower levels of complexity compared with other channels between innervation zones and muscle tendons. The study provides a novel point of view of the EMG-torque relation in the complexity domain, and reveals its alterations post stroke, which are associated with complex neural and muscular changes post stroke. The slope difference between channels with regard to innervation zones also confirms the relevance of electrode position in surface EMG analysis.

  18. The Mediator Complex MED15 Subunit Mediates Activation of Downstream Lipid-Related Genes by the WRINKLED1 Transcription Factor.

    Science.gov (United States)

    Kim, Mi Jung; Jang, In-Cheol; Chua, Nam-Hai

    2016-07-01

    The Mediator complex is known to be a master coordinator of transcription by RNA polymerase II, and this complex is recruited by transcription factors (TFs) to target promoters for gene activation or repression. The plant-specific TF WRINKLED1 (WRI1) activates glycolysis-related and fatty acid biosynthetic genes during embryogenesis. However, no Mediator subunit has yet been identified that mediates WRI1 transcriptional activity. Promoter-β-glucuronidase fusion experiments showed that MEDIATOR15 (MED15) is expressed in the same cells in the embryo as WRI1. We found that the Arabidopsis (Arabidopsis thaliana) MED15 subunit of the Mediator complex interacts directly with WRI1 in the nucleus. Overexpression of MED15 or WRI1 increased transcript levels of WRI1 target genes involved in glycolysis and fatty acid biosynthesis; these genes were down-regulated in wild-type or WRI1-overexpressing plants by silencing of MED15 However, overexpression of MED15 in the wri1 mutant also increased transcript levels of WRI1 target genes, suggesting that MED15 also may act with other TFs to activate downstream lipid-related genes. Chromatin immunoprecipitation assays confirmed the association of MED15 with six WRI1 target gene promoters. Additionally, silencing of MED15 resulted in reduced fatty acid content in seedlings and mature seeds, whereas MED15 overexpression increased fatty acid content in both developmental stages. Similar results were found in wri1 mutant and WRI1 overexpression lines. Together, our results indicate that the WRI1/MED15 complex transcriptionally regulates glycolysis-related and fatty acid biosynthetic genes during embryogenesis. © 2016 American Society of Plant Biologists. All Rights Reserved.

  19. Complexities in understanding the role of compensation-related factors on recovery from whiplash-associated disorders: discussion paper 2.

    Science.gov (United States)

    Carroll, Linda J; Connelly, Luke B; Spearing, Natalie M; Côté, Pierre; Buitenhuis, Jan; Kenardy, Justin

    2011-12-01

    Focused discussion. To present some of the complexities in conducting research on the role of compensation and compensation-related factors in recovery from whiplash-associated disorders (WAD) and to suggest directions for future research. There is divergence of opinion, primary research findings, and systematic reviews on the role of compensation and/or compensation-related factors in WAD recovery. The topic of research of compensation/compensation-related factors was discussed at an international summit meeting of 21 researchers from diverse fields of scientific enquiry. This article summarizes the main points raised in that discussion. Traffic injury compensation is a complex sociopolitical construct, which varies widely across jurisdictions. This leads to conceptual and methodological challenges in conducting and interpreting research in this area. It is important that researchers and their audiences be clear about what aspect of the compensation system is being addressed, what compensation-related variables are being studied, and what social/economic environment the compensation system exists in. In addition, summit participants also recommended that nontraditional, sophisticated study designs and analysis strategies be employed to clarify the complex causal pathways and mechanisms of effects. Care must be taken by both researchers and their audiences not to overgeneralize or confuse different aspects of WAD compensation. In considering the role of compensation/compensation-related factors on WAD and WAD recovery, it is important to retain a broad-based conceptualization of the range of biological, psychological, social, and economic factors that combine and interact to define and determine how people recover from WAD.

  20. Relations Between Nonverbal and Verbal Social Cognitive Skills and Complex Social Behavior in Children and Adolescents with Autism.

    Science.gov (United States)

    Demopoulos, Carly; Hopkins, Joyce; Lewine, Jeffrey D

    2016-07-01

    Although there is an extensive literature on domains of social skill deficits in individuals with Autism Spectrum Disorders (ASD), little research has examined the relation between specific social cognitive skills and complex social behaviors in daily functioning. This was the aim of the present study. Participants were 37 (26 male and 11 female) children and adolescents aged 6-18 years diagnosed with ASD. To determine the amount of variance in parent-rated complex social behavior accounted for by the linear combination of five directly-assessed social cognitive variables (i.e., adult and child facial and vocal affect recognition and social judgment) after controlling for general intellectual ability, a hierarchical regression analysis was performed. The linear combination of variables accounted for 35.4 % of the variance in parent-rated complex social behavior. Vocal affect recognition in adult voices showed the strongest association with complex social behavior in ASD. Results suggest that assessment and training in vocal affective comprehension should be an important component of social skills interventions for individuals with ASD.

  1. Activation of CO2 and Related Small Molecules by Neopentyl-Derivatized Uranium Complexes

    OpenAIRE

    Schmidt, Anna-Corina

    2015-01-01

    The world´s concern about the environment has continued to intensify as the effects of greenhouse gases or complicated work-up and disposal of radioactive substances become more obvious and profound. Unsurprisingly, the number of publications related to the solution of these issues has greatly increased in the last 15 years. Thus, a basic understanding of the specific properties and behavior of small molecules is crucial for the reduction of greenhouse gases, which may be realized through act...

  2. Variation in predicted internal concentrations in relation to PBPK model complexity for rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Salmina, E.S.; Wondrousch, D. [UFZ Department of Ecological Chemistry, Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany); Institute for Organic Chemistry, Technical University Bergakademie Freiberg, Leipziger Str. 29, 09596 Freiberg (Germany); Kühne, R. [UFZ Department of Ecological Chemistry, Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany); Potemkin, V.A. [Department of Chemistry, South Ural State Medical University, Vorovskogo 64, 454048, Chelyabinsk (Russian Federation); Schüürmann, G. [UFZ Department of Ecological Chemistry, Helmholtz Centre for Environmental Research, Permoserstr. 15, 04318 Leipzig (Germany); Institute for Organic Chemistry, Technical University Bergakademie Freiberg, Leipziger Str. 29, 09596 Freiberg (Germany)

    2016-04-15

    The present study is motivated by the increasing demand to consider internal partitioning into tissues instead of exposure concentrations for the environmental toxicity assessment. To this end, physiologically based pharmacokinetic (PBPK) models can be applied. We evaluated the variation in accuracy of PBPK model outcomes depending on tissue constituents modeled as sorptive phases and chemical distribution tendencies addressed by molecular descriptors. The model performance was examined using data from 150 experiments for 28 chemicals collected from US EPA databases. The simplest PBPK model is based on the “K{sub ow}-lipid content” approach as being traditional for environmental toxicology. The most elaborated one considers five biological sorptive phases (polar and non-polar lipids, water, albumin and the remaining proteins) and makes use of LSER (linear solvation energy relationship) parameters to describe the compound partitioning behavior. The “K{sub ow}-lipid content”-based PBPK model shows more than one order of magnitude difference in predicted and measured values for 37% of the studied exposure experiments while for the most elaborated model this happens only for 7%. It is shown that further improvements could be achieved by introducing corrections for metabolic biotransformation and compound transmission hindrance through a cellular membrane. The analysis of the interface distribution tendencies shows that polar tissue constituents, namely water, polar lipids and proteins, play an important role in the accumulation behavior of polar compounds with H-bond donating functional groups. For compounds without H-bond donating fragments preferable accumulation phases are storage lipids and water depending on compound polarity. - Highlights: • For reliable predictions, models of a certain complexity should be compared. • For reliable predictions non-lipid fish tissue constituents should be considered. • H-donor compounds preferably accumulate in water

  3. Motor dysfunction of complex regional pain syndrome is related to impaired central processing of proprioceptive information.

    Science.gov (United States)

    Bank, Paulina J M; Peper, C Lieke E; Marinus, Johan; Beek, Peter J; van Hilten, Jacobus J

    2013-11-01

    Our understanding of proprioceptive deficits in complex regional pain syndrome (CRPS) and its potential contribution to impaired motor function is still limited. To gain more insight into these issues, we evaluated accuracy and precision of joint position sense over a range of flexion-extension angles of the wrist of the affected and unaffected sides in 25 chronic CRPS patients and in 50 healthy controls. The results revealed proprioceptive impairment at both the patients' affected and unaffected sides, characterized predominantly by overestimation of wrist extension angles. Precision of the position estimates was more prominently reduced at the affected side. Importantly, group differences in proprioceptive performance were observed not only for tests at identical percentages of each individual's range of wrist motion but also when controls were tested at wrist angles that corresponded to those of the patient's affected side. More severe motor impairment of the affected side was associated with poorer proprioceptive performance. Based on additional sensory tests, variations in proprioceptive performance over the range of wrist angles, and comparisons between active and passive displacements, the disturbances of proprioceptive performance most likely resulted from altered processing of afferent (and not efferent) information and its subsequent interpretation in the context of a distorted "body schema." The present results point at a significant role for impaired central processing of proprioceptive information in the motor dysfunction of CRPS and suggest that therapeutic strategies aimed at identification of proprioceptive impairments and their restoration may promote the recovery of motor function in CRPS patients. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.

  4. Variation in predicted internal concentrations in relation to PBPK model complexity for rainbow trout

    International Nuclear Information System (INIS)

    Salmina, E.S.; Wondrousch, D.; Kühne, R.; Potemkin, V.A.; Schüürmann, G.

    2016-01-01

    The present study is motivated by the increasing demand to consider internal partitioning into tissues instead of exposure concentrations for the environmental toxicity assessment. To this end, physiologically based pharmacokinetic (PBPK) models can be applied. We evaluated the variation in accuracy of PBPK model outcomes depending on tissue constituents modeled as sorptive phases and chemical distribution tendencies addressed by molecular descriptors. The model performance was examined using data from 150 experiments for 28 chemicals collected from US EPA databases. The simplest PBPK model is based on the “K_o_w-lipid content” approach as being traditional for environmental toxicology. The most elaborated one considers five biological sorptive phases (polar and non-polar lipids, water, albumin and the remaining proteins) and makes use of LSER (linear solvation energy relationship) parameters to describe the compound partitioning behavior. The “K_o_w-lipid content”-based PBPK model shows more than one order of magnitude difference in predicted and measured values for 37% of the studied exposure experiments while for the most elaborated model this happens only for 7%. It is shown that further improvements could be achieved by introducing corrections for metabolic biotransformation and compound transmission hindrance through a cellular membrane. The analysis of the interface distribution tendencies shows that polar tissue constituents, namely water, polar lipids and proteins, play an important role in the accumulation behavior of polar compounds with H-bond donating functional groups. For compounds without H-bond donating fragments preferable accumulation phases are storage lipids and water depending on compound polarity. - Highlights: • For reliable predictions, models of a certain complexity should be compared. • For reliable predictions non-lipid fish tissue constituents should be considered. • H-donor compounds preferably accumulate in water, polar

  5. Magneto-Induced ac Electrical Permittivity of Metal-Dielectric Composites with a Two Characteristic Length Scales Periodic Microstructure

    International Nuclear Information System (INIS)

    Strelniker, Y.M.; Bergman, D.J.

    1998-01-01

    A new effect was recently predicted in conducting composites that have a periodic microstructure: an induced strongly anisotropic dc magneto-resistance. This phenomenon is already verified on high mobility n-GaAs films. Here we discuss the possibility of observing analogous behavior in the ac electric permittivity of a metal-dielectric composite with a periodic microstructure in the presence of a strong magnetic field. We developed new analytical and numerical methods to treat the low-frequency magneto-optical properties in composite media with both disordered and periodic conducting micro-structures. Those methods allow us to study composites with inclusions of arbitrary shape (and arbitrary volume fraction) at arbitrarily strong magnetic field. This is exploited in order to calculate an effective dielectric tensor for this system as a function of applied magnetic field and ac frequency. We show that in a non-dilute metal-dielectric composite medium the magneto-plasma resonance and the cyclotron resonance depend upon both the applied magnetic field as well as on the geometric shape of the inclusion. Near such a resonance, it is possible to achieve large values for the ratio of the off-diagonal-to-diagonal electric permittivity tensor components, ε xy /ε xx , (since ε xx →0, while ε xy ≠0), which is analogous to similar ratio of the resistivity tensor components, ρ xy /ρ xx , in the case of dc magneto-transport problem. Motivated by this observation and by results of previous studies of dc magneto-transport in composite conductors, we then performed a numerical study of the ac magneto-electric properties of a particular metal-dielectric composite film with a periodic columnar microstructure which has a two characteristic length scales. The unit cell of such composite is prepared as follows: We placed the conducting square (in cross section) rods (first characteristic length scale) along the perimeter of the unit cell in order to create a dielectric host

  6. Pre-attentive processing of spectrally complex sounds with asynchronous onsets: an event-related potential study with human subjects.

    Science.gov (United States)

    Tervaniemi, M; Schröger, E; Näätänen, R

    1997-05-23

    Neuronal mechanisms involved in the processing of complex sounds with asynchronous onsets were studied in reading subjects. The sound onset asynchrony (SOA) between the leading partial and the remaining complex tone was varied between 0 and 360 ms. Infrequently occurring deviant sounds (in which one out of 10 harmonics was different in pitch relative to the frequently occurring standard sound) elicited the mismatch negativity (MMN), a change-specific cortical event-related potential (ERP) component. This indicates that the pitch of standard stimuli had been pre-attentively coded by sensory-memory traces. Moreover, when the complex-tone onset fell within temporal integration window initiated by the leading-partial onset, the deviants elicited the N2b component. This indexes that involuntary attention switch towards the sound change occurred. In summary, the present results support the existence of pre-perceptual integration mechanism of 100-200 ms duration and emphasize its importance in switching attention towards the stimulus change.

  7. Zebrafish and relational memory: Could a simple fish be useful for the analysis of biological mechanisms of complex vertebrate learning?

    Science.gov (United States)

    Gerlai, Robert

    2017-08-01

    Analysis of the zebrafish allows one to combine two distinct scientific approaches, comparative ethology and neurobehavioral genetics. Furthermore, this species arguably represents an optimal compromise between system complexity and practical simplicity. This mini-review focuses on a complex form of learning, relational learning and memory, in zebrafish. It argues that zebrafish are capable of this type of learning, and it attempts to show how this species may be useful in the analysis of the mechanisms and the evolution of this complex brain function. The review is not intended to be comprehensive. It is a short opinion piece that reflects the author's own biases, and it draws some of its examples from the work coming from his own laboratory. Nevertheless, it is written in the hope that it will persuade those who have not utilized zebrafish and who may be interested in opening their research horizon to this relatively novel but powerful vertebrate research tool. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Health-related Quality of Life after complex rectal surgery for primary advanced rectal cancer and locally recurrent rectal cancer

    DEFF Research Database (Denmark)

    Thaysen, Henriette Vind

    2013-01-01

    postoperative morbidity, Health-related Quality of Life (HRQoL) is an important issue. The overall aim of this thesis was therefore to evaluate HRQoL in patients with PARC and LRRC treated with COMP-RCS and curative intent. In study I a review of the literature was undertaken to provide an overview of HRQo......Advances in the treatment of rectal cancer, have made it possible to perform complex rectal cancer surgery (COMP-RCS) with curative intent in patients with primary advanced rectal caner (PARC) and local recurrent rectal cancer (LRRC). Due to the complexity of the treatment and its high...... in the study was 164 (86%) patients treated with standard rectal cancer surgery (STAN-RCS). The Danish version showed satisfactory psychometric properties for the scales concerning body image, sexual functioning, male sexual problems and defecations problems. Reduced psychometric properties were found...

  9. Graph Cellular Automata with Relation-Based Neighbourhoods of Cells for Complex Systems Modelling: A Case of Traffic Simulation

    Directory of Open Access Journals (Sweden)

    Krzysztof Małecki

    2017-12-01

    Full Text Available A complex system is a set of mutually interacting elements for which it is possible to construct a mathematical model. This article focuses on the cellular automata theory and the graph theory in order to compare various types of cellular automata and to analyse applications of graph structures together with cellular automata. It proposes a graph cellular automaton with a variable configuration of cells and relation-based neighbourhoods (r–GCA. The developed mechanism enables modelling of phenomena found in complex systems (e.g., transport networks, urban logistics, social networks taking into account the interaction between the existing objects. As an implementation example, modelling of moving vehicles has been made and r–GCA was compared to the other cellular automata models simulating the road traffic and used in the computer simulation process.

  10. The relative contribution of natural zinc complexing agents and ZnSO4 to growth and zinc nutrition of maize

    International Nuclear Information System (INIS)

    Kumar, M.; Prasad, B.

    1989-01-01

    Relative evaluation of different natural zinc-complexes indicated that application of Zn-FA 2 (PM), Zn-FA 3 (Comp), Zn-FA 1 (BGS), Zn-FA 5 (PR), Zn-FA 4 (SS) and ZnSO 4 significantly enhanced the drymatter yield and zinc uptake by maize. The natural zinc-complexes in particular increased, to a greater extent, the uptake of both native and applied sources than that observed with ZnSO 4 as zinc carrier. Significant positive relationship between self-diffusion coefficient of Zn and drymatter yield and uptake of zinc by maize suggested that diffusion is responsible for the supply of zinc from ambient soil matrix to plant roots. (author). 12 refs., 5 tabs

  11. A critical study of the alkalimetric titration of mannitoboric acid complex in relation to the determination of boron in glass and related materials

    International Nuclear Information System (INIS)

    Sinha, B.C.; Dasgupta, S.

    1976-01-01

    The effect of mannitol concentration on the slope of ΔpH/Δv at the equivalence point of neutralisation of mannitoboric acid has been studied. The slope is observed to be dependent on mannitol concentration and it increases with increasing reagent concentration. The minimum pH at which titration of mannitoboric acid complex is possible without any significant error has been found to be 6.4 with a mannitol concentration of at least 15 g/50 ml of solution although the stoichiometric equivalence pH is 9.0. Based on the result of the study, a simple and accurate method has been worked out for the determination of B 2 0 3 up to 141 mg/50 ml in glass and related materials. The titration of mannitoboric acid complex is carried out at the minimum equivalence pH of 6.4 to minimise precipitation of hydroxides and phosphates of certain cations. The interference due to various elements such as Al, Fe, Zr, Pb and Zn when present are eliminated by complexing them with EDTA. Fluorine above 40 mg/50 ml interferes with the determination. (author)

  12. Relating Topological Determinants of Complex Networks to Their Spectral Properties: Structural and Dynamical Effects

    Science.gov (United States)

    Castellano, Claudio; Pastor-Satorras, Romualdo

    2017-10-01

    The largest eigenvalue of a network's adjacency matrix and its associated principal eigenvector are key elements for determining the topological structure and the properties of dynamical processes mediated by it. We present a physically grounded expression relating the value of the largest eigenvalue of a given network to the largest eigenvalue of two network subgraphs, considered as isolated: the hub with its immediate neighbors and the densely connected set of nodes with maximum K -core index. We validate this formula by showing that it predicts, with good accuracy, the largest eigenvalue of a large set of synthetic and real-world topologies. We also present evidence of the consequences of these findings for broad classes of dynamics taking place on the networks. As a by-product, we reveal that the spectral properties of heterogeneous networks built according to the linear preferential attachment model are qualitatively different from those of their static counterparts.

  13. Falls, a fear of falling and related factors in older adults with complex chronic disease.

    Science.gov (United States)

    Lee, JuHee; Choi, MoonKi; Kim, Chang Oh

    2017-12-01

    To identify factors influencing falls and the fear of falling among older adults with chronic diseases in Korea. The fear of falling and falls in older adults are significant health problems towards which healthcare providers should direct their attention. Further investigation is needed to improve nursing practice specifically decreasing risk of falls and the fear of falling in Korea. Descriptive, cross-sectional survey. A convenience sample of 108 patients was recruited at the geriatric outpatient department of a tertiary hospital in Seoul, Korea. Demographic characteristics, comorbidities, medication use, fall history, level of physical activity, activities of daily living, mobility, muscle strength, and a fear of falling were investigated. Student's t tests, chi-square tests and multiple linear regressions were used in statistical analysis. Thirty-six participants (33.3%) among 108 subjects reported experiencing ≥1 falls in the past year. Marital status and the use of antipsychotics were associated with falls, while other factors were not significantly related to falls. Only benign prostatic hypertrophy and polypharmacy were significantly related to the fear of falling in the analysis of the relationships between chronic disease, medication use and fear of falling. In the regression model, the number of comorbidities, level of physical activity, activities of daily living and mobility were predictors of a fear of falling. Medication use was marginally significant, in the model. Increasing physical activity, functional fitness and physical independence is important to decrease the fear of falling, and to encourage active and healthy lives in older adults. The findings from this study provide evidence for the development of nursing interventions for older adults. We recommend early screening for a fear of falling and nursing interventions to decrease the fear of falling through enhancing physical activity level and function. © 2017 John Wiley & Sons Ltd.

  14. Effect of the type of metal on the electrical conductivity and thermal properties of metal complexes: The relation between ionic radius of metal complexes and electrical conductivity

    Science.gov (United States)

    Morgan, Sh. M.; El-Ghamaz, N. A.; Diab, M. A.

    2018-05-01

    Co(II) complexes (1-4) and Ni(II) complexes (5-8) were prepared and characterized by elemental analysis, IR spectra and thermal analysis data. Thermal decomposition of all complexes was discussed using thermogravimetric analysis. The dielectric properties and alternating current conductivity were investigated in the frequency range 0.1-100 kHz and temperature range 300-660 K. The thermal activation energies of electrical conductivity (ΔE1 and ΔE2) values for complexes were calculated and discussed. The values of ΔE1 and ΔE2 for complexes (1-8) were found to decrease with increasing the frequency. Ac electrical conductivity (σac) values increases with increasing temperatures and the values of σac for Co(II) complexes are greater than Ni(II) complexes. Co(II) complexes showed a higher conductivity than other Ni(II) complexes due to the higher crystallinity as confirmed by X-ray diffraction analysis.

  15. Direct view at colossal permittivity in donor-acceptor (Nb, In) co-doped rutile TiO2

    International Nuclear Information System (INIS)

    Mandal, Suman; Pal, Somnath; Hazarika, Abhijit; Kundu, Asish K.; Menon, Krishnakumar S. R.; Rioult, Maxime; Belkhou, Rachid

    2016-01-01

    Topical observations of colossal permittivity (CP) with low dielectric loss in donor-acceptor cations co-doped rutile TiO 2 have opened up several possibilities in microelectronics and energy-storage devices. Yet, the precise origin of the CP behavior, knowledge of which is essential to empower the device integration suitably, is highly disputed in the literature. From spectromicroscopic approach besides dielectric measurements, we explore that microscopic electronic inhomogeneities along with the nano-scale phase boundaries and the low temperature polaronic relaxation are mostly responsible for such a dielectric behavior, rather than electron-pinned defect-dipoles/grain-boundary effects as usually proposed. Donor-acceptor co-doping results in a controlled carrier-hopping inevitably influencing the dielectric loss while invariably upholding the CP value.

  16. Direct view at colossal permittivity in donor-acceptor (Nb, In) co-doped rutile TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Suman, E-mail: suman.mandal@sscu.iisc.ernet.in; Pal, Somnath; Hazarika, Abhijit [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bengaluru 560012 (India); Kundu, Asish K.; Menon, Krishnakumar S. R. [Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India); Rioult, Maxime; Belkhou, Rachid [Synchrotron SOLEIL, L' Orme des Merisiers Saint-Aubin, 91192 Gif-sur-Yvette (France)

    2016-08-29

    Topical observations of colossal permittivity (CP) with low dielectric loss in donor-acceptor cations co-doped rutile TiO{sub 2} have opened up several possibilities in microelectronics and energy-storage devices. Yet, the precise origin of the CP behavior, knowledge of which is essential to empower the device integration suitably, is highly disputed in the literature. From spectromicroscopic approach besides dielectric measurements, we explore that microscopic electronic inhomogeneities along with the nano-scale phase boundaries and the low temperature polaronic relaxation are mostly responsible for such a dielectric behavior, rather than electron-pinned defect-dipoles/grain-boundary effects as usually proposed. Donor-acceptor co-doping results in a controlled carrier-hopping inevitably influencing the dielectric loss while invariably upholding the CP value.

  17. THE CITY- THE PORT-THE SEA The evolutive features of a complex relation

    Directory of Open Access Journals (Sweden)

    Mario Coletta

    2014-01-01

    Full Text Available The balanced relation between the city and the sea was at the centre of the Greek philosophy. During the flourishing of the Hellenic civilization, Plato began wondering about the appropriate characteristics of a site for an urban settlement near the sea. An ideal-type of urban settlement model resulted, based on accessibility, safety, hygienism, productivity, proximity to energy sources, prosperity.Renaissance artists appealed to the ancient knowledge in order to renew the treatises about architecture and town planning, in the perspective of building new models aiming at making perfect the structure and the soul of the city through a strictly geometric form.The harbour rose with open arms, towards the sea; a hug aiming at showing the pleasure of meeting,  guaranteeing shelter, protection, safety and friendly welcome.On the contrary, the harbour turns its back to the city and sometimes it moves the city away, in order to keep a certain distance.Physical and institutional barriers intervene between the city and the sea, claiming autonomous political-administrative and planning roles, often hindering, instead of fostering, natural osmotic processes, debasing functions, roles and social, economic, political and cultural interests of reciprocal belonging.Almost everywhere the legislative evolution has followed, and not preceded, the territorial devastation of settlements along the coasts – especially the devastation spontaneously risen – and only later has tried to hold in check a phenomenon sadly fallen in the ways of doing and the emptiness of thinking, letting the “habit of doing” prevail the conservative legislation based on placing pickets to the “not to do” approach; that situation in the light of an economic power become the director of political power, conditioned at opening eyes on doing for half-closing eyes on business.The new city-sea relation has to be studied as a valorisation, not as mere protective measures prescribed by

  18. Embedded interruptions and task complexity influence schema-related cognitive load progression in an abstract learning task.

    Science.gov (United States)

    Wirzberger, Maria; Esmaeili Bijarsari, Shirin; Rey, Günter Daniel

    2017-09-01

    Cognitive processes related to schema acquisition comprise an essential source of demands in learning situations. Since the related amount of cognitive load is supposed to change over time, plausible temporal models of load progression based on different theoretical backgrounds are inspected in this study. A total of 116 student participants completed a basal symbol sequence learning task, which provided insights into underlying cognitive dynamics. Two levels of task complexity were determined by the amount of elements within the symbol sequence. In addition, interruptions due to an embedded secondary task occurred at five predefined stages over the task. Within the resulting 2x5-factorial mixed between-within design, the continuous monitoring of efficiency in learning performance enabled assumptions on relevant resource investment. From the obtained results, a nonlinear change of learning efficiency over time seems most plausible in terms of cognitive load progression. Moreover, different effects of the induced interruptions show up in conditions of task complexity, which indicate the activation of distinct cognitive mechanisms related to structural aspects of the task. Findings are discussed in the light of evidence from research on memory and information processing. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. [Innovative culture and diagnosis related groups in a high complexity hospital, Colombia].

    Science.gov (United States)

    Gorbanev, Iouri; Agudelo-Londoño, Sandra; Cortes, Ariel; Yepes, Francisco J

    2016-04-01

    Objectives To characterize the perception of Diagnosis-Related Groups (DRGs) as an innovation among physicians, nurses and administrative staff in a hospital in Colombia. Methods A case study of innovative culture in a hospital. Surveys and focus groups were carried out with the medical, nursing and administrative staff. Descriptive statistics were calculated for the perceptions of innovative culture. Comparative analysis was done between professional groups. The results of the focus groups were transcribed and analyzed to deepen the findings of the surveys. Results Significant differences were found in perceptions of the innovative culture. The nursing staff were more enthusiastic than doctors when evaluating the innovative culture and leadership. Physicians felt more autonomy when discussing professional issues. Administrative staff assessed the Hospital's disposition to acquire new medical technologies as higher than that of physicians. The three groups know little about DRG's. Conclusions When implementing a health innovation it is advisable to analyze its effect on the professionals who participate in the implementation. Physicians perceive DRGs as a threat to their professional autonomy, while nurses see it as a pro-innovation force. It is important to involve nursing and administrative staff when implementing this kind of innovation.

  20. Rapunzel’s complex: Social relations, and sexuality affectivity of adolescents with HIV/AIDS

    Directory of Open Access Journals (Sweden)

    Luciana França Cescon

    2012-09-01

    Full Text Available The present work aims to reflect on the influence of HIV / AIDS on social relations, sexuality and adolescent affectivity. We conducted a literature review and subsequent theoretical discussion on the topic, with the methodology of qualitative analysis of texts and scientific articles. The findings of the study demonstrated that it is necessary to fully consider the various psychosocial aspects of this dynamic, since the psychological aspects significantly influence disease progression and quality of life of HIV patient. For adolescents, this influence becomes even greater, because puberty is a specific stage of biological development, emotional and social, where social interaction plays an important role for the construction of the subject's personality. It is hoped that this study may contribute to the reflection on the importance of creating themselves coping strategies and health care interventions geared to this particular group, especially with regard to the psychologist, who should seek to accommodate these demands subjects, contributing to a healthy psychosocial development, considering its specific features.

  1. Something fishy? News media presentation of complex health issues related to fish consumption guidelines.

    Science.gov (United States)

    Greiner, Amelia; Clegg Smith, Katherine; Guallar, Eliseo

    2010-11-01

    The news media are an important source of dietary information. Understanding news content, particularly the portrayal of risks and benefits of certain foods, is relevant for effective public health communication. Fish consumption may reduce risk for CVD and aid neonatal development, but recent work shows public confusion about the benefits of fish, challenged by the evidence of mercury and other contaminants in fish. We present an analysis of the messages about fish in US news media over 15 years, identifying trends in coverage and highlighting implications of current messaging. We conducted a descriptive text analysis and coded for manifest content: locality of focus, story frame, reference to studies, inclusion of government guidelines and portrayal of uncertainty. We identified chronological patterns and analysed the data for statistically significant relationships between media source and content. News stories were selected from five daily newspapers and five television networks (1993-2007). We analysed 310 health-related news stories on fish. Risk messages outweighed benefit messages four to one, and health benefits only became prominent after 2002. No difference existed in coverage topic by news source. Fish consumption has increasingly become a national issue. With the bulk of messages about fish consumption focused on risk, the benefits may be lost to consumers. This gap creates a need for public health to work with news media to more effectively communicate benefits and risks around fish consumption and health and to consider options for communicating tailored information where it can be more readily utilised.

  2. Work-related outcome after acute coronary syndrome: Implications of complex cardiac rehabilitation in occupational medicine.

    Science.gov (United States)

    Lamberti, Monica; Ratti, Gennaro; Gerardi, Donato; Capogrosso, Cristina; Ricciardi, Gianfranco; Fulgione, Cosimo; Latte, Salvatore; Tammaro, Paolo; Covino, Gregorio; Nienhaus, Albert; Grazillo, Elpidio Maria; Mallardo, Mario; Capogrosso, Paolo

    2016-01-01

    Coronary heart disease is frequent in the working-age population. Traditional outcomes, such as mortality and hospital readmission, are useful for evaluating prognosis. Fit-for-work is an emerging outcome with clinical as well as socioeconomic significance. We describe the possible benefit of a cardiac rehabilitation (CR) program for return to work (RTW) after acute coronary syndrome (ACS). We evaluated 204 patients with recent ACS. They were divided into 4 groups on the basis of their occupational work load: very light (VL), light (L), moderate (M), and heavy (H). Work-related outcomes were assessed with the Work Performance Scale (WPS) of the Functional Status Questionnaire and as "days missed from work" (DMW) in the previous 4 weeks. The variables considered for outcomes were percent ejection fraction, functional capacity expressed in metabolic equivalents (METs), and participation or non-participation in the CR program (CR+ and CR-). One hundred thirty (66%) patients took part in the CR program. Total WPS scores for CR+ and CR- subgroups were VL group: 18±4 vs. 14±4 (p workplace, in particular among clerical workers. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  3. Low-frequency permittivity of spin-density wave in (TMTSF)2PF6 at low temperatures

    DEFF Research Database (Denmark)

    Nad, F.; Monceau, P.; Bechgaard, K.

    1995-01-01

    Conductivity and permittivity epsilon of(TMTSF)(2)PF6 have been measured at low frequencies of (10(2)-10(7) Hz) at low temperatures below the spin-density wave (SDW) transition temperature T-p. The temperature dependence of the conductivity shows a deviation from thermally activated behavior at T...

  4. Origin of colossal dielectric permittivity of rutile Ti₀.₉In₀.₀₅Nb₀.₀₅O₂: single crystal and polycrystalline.

    Science.gov (United States)

    Song, Yongli; Wang, Xianjie; Sui, Yu; Liu, Ziyi; Zhang, Yu; Zhan, Hongsheng; Song, Bingqian; Liu, Zhiguo; Lv, Zhe; Tao, Lei; Tang, Jinke

    2016-02-12

    In this paper, we investigated the dielectric properties of (In + Nb) co-doped rutile TiO2 single crystal and polycrystalline ceramics. Both of them showed colossal, up to 10(4), dielectric permittivity at room temperature. The single crystal sample showed one dielectric relaxation process with a large dielectric loss. The voltage-dependence of dielectric permittivity and the impedance spectrum suggest that the high dielectric permittivity of single crystal originated from the surface barrier layer capacitor (SBLC). The impedance spectroscopy at different temperature confirmed that the (In + Nb) co-doped rutile TiO2 polycrystalline ceramic had semiconductor grains and insulating grain boundaries, and that the activation energies were calculated to be 0.052 eV and 0.35 eV for grain and grain boundary, respectively. The dielectric behavior and impedance spectrum of the polycrystalline ceramic sample indicated that the internal barrier layer capacitor (IBLC) mode made a major contribution to the high ceramic dielectric permittivity, instead of the electron-pinned defect-dipoles.

  5. The relation between intensity and complexity of coronary artery lesion and oxidative stress in patients with acute coronary syndrome.

    Science.gov (United States)

    Turan, Turhan; Menteşe, Ümit; Ağaç, Mustafa Tarık; Akyüz, Ali Rıza; Kul, Selim; Aykan, Ahmet Çağrı; Bektaş, Hüseyin; Korkmaz, Levent; Öztaş Menteşe, Seda; Dursun, İhsan; Çelik, Şükrü

    2015-10-01

    Oxidative stress plays a major role in the development of atherosclerosis. However, the relationship between oxidative stress and complexity and intensity of coronary artery disease is less clear. The aim of this study is to assess the relationship between oxidative stress markers and the complexity and intensity of coronary artery disease in patients with acute coronary syndrome (ACS). Sixty-seven consecutive patients with an early phase of ACS (=22). Likewise patients were divided into two CAD severity groups according to the median Gensini score of 64: less intensive CAD with Gensini score (=64. Blood samples were taken in 1 hour within administration in order to measure total oxidative status (TOS) and total antioxidant capacity (TAC) levels determined by Erel method. Oxidative stress index (OSI) was calculated by TOS /TAC. There was no significant difference between the two SYNTAX groups for oxidative stress markers. Median TOS and OSI values were significantly high in the intensive CAD group (p=0.005, p=0.04, respectively). The Gensini score was positively correlated with TOS and OSI (p=0.003, p=0.02, respectively). Oxidative stress markers may be considered supportive laboratory parameters related to CAD intensity but not complexity in ACS patients.

  6. Informing climate-related decisions in complex river basins: A comparative assessment

    Science.gov (United States)

    Pulwarty, R. S.; Bark, R. H.; Maia, R.; Udall, B.

    2010-12-01

    Integrated water resources management provides an important governance framework to achieve climate-related adaptation measures across socio-economic, environmental and administrative systems. Adaptation includes technical changes that improve water use efficiency, early warning, demand management (e.g. through metering and pricing), and institutional changes that improve the tradability of water rights. Supply-side strategies generally involve increases in storage capacity, abstraction from watercourses, and water transfers. Incentives for improving water-use efficiency, hold considerable promise for water savings and the reallocation of water to highly valued uses. However, conflicts exist between processes and goals of water management and governance. These militate against the effectiveness of using scientific information to meet short-term needs in the context of reducing longer-term vulnerabilities such as for “increasing water supply while meeting environmental needs.” A complete analysis of the effects of climate change on human water uses would consider cross-sector interactions, including the impacts of transfers of the use of water from one sector to another. In this presentation we will review the challenges and lessons provided in water resources management in the context of a changing climate. Lessons are drawn from watersheds around the world including the Colorado, Columbia, Murray-Darling, Guadiana and others. We explore how watershed managers and researchers are attempting to address the risks associated with climatic change and potential surprises. In spite of numerous climate impacts studies the management of the cumulative impacts of extremes (droughts, floods etc.) remains reactive and crisis-driven. Most recommendations stay within the applied sciences realm of technological interventions and supply driven approaches. Clearly more is needed to inform an integrated watershed management approaches in which adaptive management functions as

  7. From lizard body form to serpentiform morphology: The atlas-axis complex in African cordyliformes and their relatives.

    Science.gov (United States)

    Čerňanský, Andrej

    2016-04-01

    The comparative vertebral morphology of the atlas-axis complex in cordyliforms, xantusiid and several skinks is studied here. These lizards are particularly interesting because of their different ecological adaptations and anti-predation strategies, where conformation ranges from the lizard-like body to a snake-like body. This transition to serpentiform morphology shows several evolutionary patterns in the atlas-axis complex: 1) the zygapophyseal articulations are lost in the early stage of the transition. In contrast to mammals, the atlas is more or less locked to the axis in lepidosaurs, but the absence of zygapophyseal articulation releases this locking for rotation. However despite its serpentiform morphology, Chamaesaura is different, in possessing this articulation; 2) the first intercentrum of Chamaesaura and Tetradactylus africanus (serpentiform grass-swimmers) is fully curved anteriorly, underlying the occipital condyle. While this limits ventral skull rotation beyond a certain angle, it locks the skull, which is a crucial adaptation for a sit-and-wait position in grassland habitats that needs to keep the head stabilized; and 3) in Acontias, most of the atlas articular surface with the occipital condyle is formed by the lateral aspect of the articulation area relative to the area located in the dorsal region of the slightly reduced intercentrum. A similar state occurs in amphisbaenians, most likely reflecting a fossorial lifestyle of the limbless lizards. Although Chamaesaura and Tetradactylus live sympatrically in grasslands, Chamaesaura differs in several ways in atlas-axis complex: for example, aforementioned presence of the atlas-axis zygapophyseal articulation, and long posterodorsal processes. Its occipital condyle protrudes further posteriorly, placing the atlas-axis complex further from the endocranium than in Tetradactylus. Hence, adaptation in the same niche, even among sister clades, can lead to different atlas-axis morphology due to different

  8. The Multilateral Convention to Implement Tax Treaty Related Measures to Prevent BEPS—Some Thoughts on Complexity and Uncertainty

    Directory of Open Access Journals (Sweden)

    Kleist David

    2018-04-01

    Full Text Available The Multilateral Convention to Implement Tax Treaty Related Measures to Prevent Base Erosion and Profit Shifting (MLI, which was signed in June 2017, raises a multitude of questions relating not only to the text of the treaty provisions but also to the way the MLI will interact with tax treaties, for instance, and what it will mean for the future development of tax treaty law and international cooperation in tax matters. This article focuses on two aspects of the MLI. First, it deals with the substance of the MLI by providing an overview of its background and content, including the many options available to the contracting states under the MLI. Second, some thoughts are presented on the effects of the MLI in terms of complexity and uncertainty.

  9. Communicating in complex situations: a normative approach to HIV-related talk among parents who are HIV+.

    Science.gov (United States)

    Edwards, Laura L; Donovan-Kicken, Erin; Reis, Janet S

    2014-01-01

    Parents with HIV/AIDS are confronted with unique challenges when discussing HIV-related information with their children. Strategies for navigating these challenges effectively have not been systematically examined. In this study, we conducted in-depth interviews with 76 parents with HIV/AIDS who had children ages 10-18 years. Guided by O'Keefe and Delia's definition of a complex communication situation and Goldsmith's normative approach to interpersonal communication, we examined parents' goals for discussing HIV-related information, factors that made conversations challenging, and instances where these conversational purposes conflicted with one another. Our data reveal the following parent-adolescent communication predicaments: relaying safety information about HIV while minimizing child anxiety, modeling open family communication without damaging one's parental identity, and balancing parent-child relational needs amid living with an unpredictable health condition. Parents also described a variety of strategies for mitigating challenges when discussing HIV-related topics. Strategies parents perceived as effective included reframing HIV as a chronic, manageable illness; keeping talk educational; and embedding HIV-related topics within more general conversations. The theoretical and practical applications of these findings are discussed with regard to their relevance to health communication scholars and HIV care professionals.

  10. Towards a complex systems approach in sports injury research: simulating running-related injury development with agent-based modelling.

    Science.gov (United States)

    Hulme, Adam; Thompson, Jason; Nielsen, Rasmus Oestergaard; Read, Gemma J M; Salmon, Paul M

    2018-06-18

    There have been recent calls for the application of the complex systems approach in sports injury research. However, beyond theoretical description and static models of complexity, little progress has been made towards formalising this approach in way that is practical to sports injury scientists and clinicians. Therefore, our objective was to use a computational modelling method and develop a dynamic simulation in sports injury research. Agent-based modelling (ABM) was used to model the occurrence of sports injury in a synthetic athlete population. The ABM was developed based on sports injury causal frameworks and was applied in the context of distance running-related injury (RRI). Using the acute:chronic workload ratio (ACWR), we simulated the dynamic relationship between changes in weekly running distance and RRI through the manipulation of various 'athlete management tools'. The findings confirmed that building weekly running distances over time, even within the reported ACWR 'sweet spot', will eventually result in RRI as athletes reach and surpass their individual physical workload limits. Introducing training-related error into the simulation and the modelling of a 'hard ceiling' dynamic resulted in a higher RRI incidence proportion across the population at higher absolute workloads. The presented simulation offers a practical starting point to further apply more sophisticated computational models that can account for the complex nature of sports injury aetiology. Alongside traditional forms of scientific inquiry, the use of ABM and other simulation-based techniques could be considered as a complementary and alternative methodological approach in sports injury research. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Age-related differences in warning symbol comprehension and training effectiveness: effects of familiarity, complexity, and comprehensibility.

    Science.gov (United States)

    Lesch, M F; Horrey, W J; Wogalter, M S; Powell, W R

    2011-10-01

    Age-related changes in selective attention, inhibitory efficiency, and the ability to form new associations suggest that older adults may have greater difficulty with more complex and less comprehensible symbols. We examined comprehension of symbols varying in terms of ratings of familiarity, complexity, and comprehensibility, by younger (aged 18-35) and older (aged 55-70) adults. It was found that older adults have greater difficulty than younger adults in comprehending warning symbols and that accident scenario training improves comprehension. Regression analyses indicated that familiarity and comprehensibility were important in determining performance on the pre-training comprehension test by both younger and older adults. However, training eliminated the effects of stimulus characteristics for younger adults, while older adults' comprehension continued to be significantly influenced by comprehensibility. We suggest that symbol design incorporates cues to knowledge to facilitate the linkage between new knowledge (i.e. the warning symbol) and relevant knowledge in long-term memory. Statement of Relevance: Symbol characteristics play an important role in age-related differences in warning symbol comprehension. To optimise comprehension by older adults, symbols should have a clear relationship with areal-world referent. Alternatively, symbol design could incorporate cues to knowledge to facilitate the linkage between new knowledge and relevant knowledge in long-term memory.

  12. Age- and gender-related regional variations of human brain cortical thickness, complexity, and gradient in the third decade.

    Science.gov (United States)

    Creze, Maud; Versheure, Leslie; Besson, Pierre; Sauvage, Chloe; Leclerc, Xavier; Jissendi-Tchofo, Patrice

    2014-06-01

    Brain functional and cytoarchitectural maturation continue until adulthood, but little is known about the evolution of the regional pattern of cortical thickness (CT), complexity (CC), and intensity or gradient (CG) in young adults. We attempted to detect global and regional age- and gender-related variations of brain CT, CC, and CG, in 28 healthy young adults (19-33 years) using a three-dimensional T1 -weighted magnetic resonance imaging sequence and surface-based methods. Whole brain interindividual variations of CT and CG were similar to that in the literature. As a new finding, age- and gender-related variations significantly affected brain complexity (P gender), all in the right hemisphere. Regions of interest analyses showed age and gender significant interaction (P left inferior parietal. In addition, we found significant inverse correlations between CT and CC and between CT and CG over the whole brain and markedly in precentral and occipital areas. Our findings differ in details from previous reports and may correlate with late brain maturation and learning plasticity in young adults' brain in the third decade. Copyright © 2013 Wiley Periodicals, Inc.

  13. Assessment of complex water pollution with heavy metals and Pyrethroid pesticides on transcript levels of metallothionein and immune related genes.

    Science.gov (United States)

    Ghazy, Haneen A; Abdel-Razek, Mohamed A S; El Nahas, Abeer F; Mahmoud, Shawky

    2017-09-01

    Alteration of immunological function of an aquatic organism can be used as an indicator for evaluating the direct effect of exposure to pollutants. The aim of this work is to assess the impact of complex water pollution with special reference to Pyrethroid pesticides and heavy metals on mRNA transcript levels of Metallothionine and some immune related genes of Nile tilapia (Oreochromas Niloticus). Residues of six heavy metals and six Pyrethroid were assessed in water as well as fish tissues at three different sites of Lake Burullus, located at Northern Egypt. Variations of water physicochemical properties associated with different levels of heavy metals at the three different sections were recorded. Tissue residues of Fe, Mn and Zn, Cu, Ni exceed water levels in contrast to elevated water level of Pb. All assessed Pyrethroids are detected in fish tissue samples with higher concentration (3-42 folds) than that found in water samples especially Cypermethrin. Significant down-regulation of expression levels of metallothionein (MT) at the three sections of the lake was observed. The expression of immune related genes (IgM) and inflammatory cytokines (TNF, IL.8 and IL.1) were affected. IgM and TNF were significantly down-regulated at eastern and western section of the lake; meanwhile the expression of IL8 is down regulated at the three sections of the lack. IL1 was significantly up-regulated at eastern and middle sections. We conclude that, variable gene expression of MT and immune-related genes at the three sections of the lack impose different response to complex water pollution in relation to variable aquatic environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Stable Isotope Evidence for a Complex Fluid Evolution of the Northwestern British Columbia Coast Ranges Related to Terrane Accretion

    Science.gov (United States)

    Moertle, J.; Holk, G. J.

    2015-12-01

    Stable isotope geochemistry reveals a complex fluid evolution for the Western Metamorphic Belt (WMB), Coast Ranges Batholith (CRB), Central Gneiss Complex (CGC) and Coast Ranges Megalineament (CRM). These fluids are a product of a complex tectonic history related to terrane accretion that includes oblique convergence, metamorphism, magmatism, and orogenic collapse. From W-to-E, these fluid systems are as follows. High-pressure greenschist-to-amphibolite facies metasedimentary rocks of the WMB record variable mineral δD (-61 to -104‰) and δ18O (e.g., quartz +9.6 to +13.4‰) values with multiple minerals in apparent isotopic equilibrium (T ~ 450-550°C) suggest a low W/R system dominated by metamorphic fluids. Variable and non-equilibrium δD (-53 to -143‰) and δ18O (e.g., biotite +2.3 to +5.3‰) values from diorites of the Quottoon pluton affected by the ductile CRM suggest a complex evolution that involved both metamorphic and meteoric-hydrothermal fluids in this dextral shear zone; these results differ from those 300 km along strike to the north that documented only metamorphic fluids in the CRM (Goldfarb et al., 1988). Our data and those of Magaritz and Taylor (1976) from granulite facies metasediments of the CGC and plutons of the western CRB reveal homogeneous δD values (-62 to -78‰) and a restricted range of δ18O values (e.g., quartz +8.5 to +11.5‰) with all minerals in equilibrium at T > 570°C indicate a system dominated by magmatic fluids. Calculated whole-rock δ18O values (~ +7‰) for the Quottoon pluton and CRB intrusive rocks suggest a mantle origin for these magmas. Reinterpretation of very low δD (< -150‰) and quartz-feldspar δ18O pairs that display extreme disequilibrium (feldspar δ18O values as low as -5‰) from the Ponder pluton, eastern CRB, and Hazelton Group point reveals that the major meteoric-hydrothermal system that affected these rocks was related to Eocene detachment faulting along the Shames Lake fault system, a

  15. A protocol for a new methodological model for work-related shoulder complex injuries: From diagnosis to rehabilitation.

    Science.gov (United States)

    Setuain, Igor; Gonzalez-Izal, Miriam; Paularena, Ainara; Luque, Jose Luis; Andersen, Lars L; Izquierdo, Mikel

    2017-02-07

    Work-related injuries of the shoulder complex represent a challenge for clinicians because of the large variety of clinical entities involved and the broad anatomic structures that can be affected. Furthermore, commonly performed orthopedic tests have demonstrated limited accuracy for diagnosing the injury despite considerable research efforts. The aim of this study protocol is therefore to describe a comprehensive approach integrating both a clinical- and functional status-based pathology and an adapted rehabilitation prescription. A longitudinal cohort study will be performed at the Department of Rehabilitation and Medical Assistance of a mutual insurance society for work-related injury management in Spain (Mutua Navarra, Pamplona, Navarra Spain). Patients will be attended by an occupational physician who specializes in work-related injuries and is part of the project team that will systematically visit all the participants. After the medical diagnosis and any requested supplementary evaluations (i.e., radiological examinations), the patients will be referred to the rehabilitation service. Before the physiotherapeutic rehabilitation program is initiated, the patients will undergo a comprehensive functional screening at the biomechanics laboratory. Using a decision-making scheme, the identified functional deficits will be used to customize the individual rehabilitation plan. The proposed objective criteria-based shoulder diagnosis and rehabilitation model could be a new effective strategy for minimizing the time required to regain functional capacity and recover from symptoms among patients with work-related shoulder injuries. The study protocol has been registered on Clinical Trials.gov as NCT02732002 (April 10 th 2016).

  16. Burkholderia humptydooensis sp. nov., a New Species Related to Burkholderia thailandensis and the Fifth Member of the Burkholderia pseudomallei Complex.

    Science.gov (United States)

    Tuanyok, Apichai; Mayo, Mark; Scholz, Holger; Hall, Carina M; Allender, Christopher J; Kaestli, Mirjam; Ginther, Jennifer; Spring-Pearson, Senanu; Bollig, Molly C; Stone, Joshua K; Settles, Erik W; Busch, Joseph D; Sidak-Loftis, Lindsay; Sahl, Jason W; Thomas, Astrid; Kreutzer, Lisa; Georgi, Enrico; Gee, Jay E; Bowen, Richard A; Ladner, Jason T; Lovett, Sean; Koroleva, Galina; Palacios, Gustavo; Wagner, David M; Currie, Bart J; Keim, Paul

    2017-03-01

    During routine screening for Burkholderia pseudomallei from water wells in northern Australia in areas where it is endemic, Gram-negative bacteria (strains MSMB43 T , MSMB121, and MSMB122) with a similar morphology and biochemical pattern to B. pseudomallei and B. thailandensis were coisolated with B. pseudomallei on Ashdown's selective agar. To determine the exact taxonomic position of these strains and to distinguish them from B. pseudomallei and B. thailandensis , they were subjected to a series of phenotypic and molecular analyses. Biochemical and fatty acid methyl ester analysis was unable to distinguish B. humptydooensis sp. nov. from closely related species. With matrix-assisted laser desorption ionization-time of flight analysis, all isolates grouped together in a cluster separate from other Burkholderia spp. 16S rRNA and recA sequence analyses demonstrated phylogenetic placement for B. humptydooensis sp. nov. in a novel clade within the B. pseudomallei group. Multilocus sequence typing (MLST) analysis of the three isolates in comparison with MLST data from 3,340 B. pseudomallei strains and related taxa revealed a new sequence type (ST318). Genome-to-genome distance calculations and the average nucleotide identity of all isolates to both B. thailandensis and B. pseudomallei , based on whole-genome sequences, also confirmed B. humptydooensis sp. nov. as a novel Burkholderia species within the B. pseudomallei complex. Molecular analyses clearly demonstrated that strains MSMB43 T , MSMB121, and MSMB122 belong to a novel Burkholderia species for which the name Burkholderia humptydooensis sp. nov. is proposed, with the type strain MSMB43 T (American Type Culture Collection BAA-2767; Belgian Co-ordinated Collections of Microorganisms LMG 29471; DDBJ accession numbers CP013380 to CP013382). IMPORTANCE Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. The genus Burkholderia consists of a diverse group of species, with

  17. Développement de la mémoire de travail et traitement des phrases complexes : Quelle relation ?

    Directory of Open Access Journals (Sweden)

    Frauenfelder Ulrich

    2012-07-01

    résultats de 48 enfants francophones monolingues, répartis en trois groupes d’âge (5-6, 8-9 et 11-12 ans, révèlent des corrélations fortes entre les scores des empans simples et complexes et les performances syntaxiques. Plus précisément, nous avons pu démontrer la valeur hautement prédictive des compétences en mémoire de travail sur l’acquisition des habiletés morphosyntaxiques en réception et en production. Ainsi, le score composite des empans complexes explique 48% de la variance des scores en compréhension syntaxique et de 16 à 30% des mesures obtenues en production spontanée. Nos résultats soutiennent donc l’hypothèse selon laquelle l’augmentation des capacités de mémoire de travail permettrait à l’enfant une maîtrise progressive des phrases complexes. L’existence d’une relation causale réciproque reste cependant à explorer.

  18. Complex impedance spectra of chip inductor using Li-Zn-Cu-Mn ferrite

    International Nuclear Information System (INIS)

    Nakamura, Tatsuya; Naoe, Masayuki; Yamada, Yoshihiro

    2006-01-01

    A multi-layer chip inductor (MCI) was fabricated using polycrystalline Li-Zn-Cu-Mn ferrite and the green-sheet technique, and its complex impedance spectrum was evaluated with the help of numerical calculations. The complex impedance spectra of the MCI component using Ni-Zn-Cu ferrite, which have been widely used for this application, were very sensitive to the residual stress and deviated much from the calculated values; however, it was found that the complex impedance spectrum of the MCI component using Li-Zn-Cu-Mn ferrite is quite well reproduced by calculation, where the complex permittivity and permeability of the polycrystalline ferrite as well as the MCI dimensions, were used. It implied that the magneto-striction effect was negligible in case of MCI using Li-Zn-Cu-Mn ferrite, and that the difference was related to magneto-strictive coefficient of the polycrystalline ferrite. Consequently, utilization of Li-Zn-Cu-Mn ferrite enabled us to easily design the complex impedance of MCI component

  19. Lactate up-regulates the expression of lactate oxidation complex-related genes in left ventricular cardiac tissue of rats.

    Directory of Open Access Journals (Sweden)

    Daniele Gabriel-Costa

    Full Text Available Besides its role as a fuel source in intermediary metabolism, lactate has been considered a signaling molecule modulating lactate-sensitive genes involved in the regulation of skeletal muscle metabolism. Even though the flux of lactate is significantly high in the heart, its role on regulation of cardiac genes regulating lactate oxidation has not been clarified yet. We tested the hypothesis that lactate would increase cardiac levels of reactive oxygen species and up-regulate the expression of genes related to lactate oxidation complex.Isolated hearts from male adult Wistar rats were perfused with control, lactate or acetate (20mM added Krebs-Henseleit solution during 120 min in modified Langendorff apparatus. Reactive oxygen species (O2●-/H2O2 levels, and NADH and NADPH oxidase activities (in enriched microsomal or plasmatic membranes, respectively were evaluated by fluorimetry while SOD and catalase activities were evaluated by spectrophotometry. mRNA levels of lactate oxidation complex and energetic enzymes MCT1, MCT4, HK, LDH, PDH, CS, PGC1α and COXIV were quantified by real time RT-PCR. Mitochondrial DNA levels were also evaluated. Hemodynamic parameters were acquired during the experiment. The key findings of this work were that lactate elevated cardiac NADH oxidase activity but not NADPH activity. This response was associated with increased cardiac O2●-/H2O2 levels and up-regulation of MCT1, MCT4, LDH and PGC1α with no changes in HK, PDH, CS, COXIV mRNA levels and mitochondrial DNA levels. Lactate increased NRF-2 nuclear expression and SOD activity probably as counter-regulatory responses to increased O2●-/H2O2.Our results provide evidence for lactate-induced up-regulation of lactate oxidation complex associated with increased NADH oxidase activity and cardiac O2●-/H2O2 driving to an anti-oxidant response. These results unveil lactate as an important signaling molecule regulating components of the lactate oxidation complex in

  20. The Gd{sub 14}Ag{sub 51} structure type and its relation to some complex amalgam structures

    Energy Technology Data Exchange (ETDEWEB)

    Tambornino, Frank; Sappl, Jonathan; Hoch, Constantin, E-mail: constantin.hoch@cup.uni-muenchen.de

    2015-01-05

    Highlights: • The Gd{sub 14}Ag{sub 51} structure type has been revisited on the basis of single crystal diffraction data. • Symmetry analysis from electron density and TEM shows the space group P6/m to be true. • Gd{sub 14}Ag{sub 51} shows good metallic behaviour. • Structure relations to alkali, alkaline-earth and rare-earth metal amalgams can be established. • Complexity values for the RE{sub 14}Ag{sub 51} structure family were calculated. - Abstract: A plethora of binary and ternary intermetallic compounds has been assigned to the Gd{sub 14}Ag{sub 51} structure type, crystallising in the hexagonal system (space group P6/m, a = 1264.30(18) pm, c = 933.58(11) pm for Gd{sub 14}Ag{sub 51}). Starting in the late 1960s, much work has been invested in the structural elucidation of these crystal structures. However, reliable single crystal data are scarce, and most structure type assignments have been performed merely on the basis of powder data. We have redetermined four representatives of the binary RE{sub 14}Ag{sub 51} structure type (RE = Y, Ce, Gd, Tb) with modern high-precision single crystal X-ray methods. The assignment of the Gd{sub 14}Ag{sub 51} structure type to space group P6/m was additionally verified by careful analysis of high resolution transmission electron micrographs. We emphasise the close relation of the Gd{sub 14}Ag{sub 51} structure type to the structures of some recently described amalgams of similar composition focussing on disorder phenomena and structural complexity. Furthermore, we provide detailed information on synthesis as well as electrical and magnetic properties for Gd{sub 14}Ag{sub 51}, the parent compound of this structure family.

  1. Phase-based treatment of a complex severely mentally ill case involving complex posttraumatic stress disorder and psychosis related to Dandy Walker syndrome

    NARCIS (Netherlands)

    Mauritz, M.W.; van de Sande, R.; Goossens, P.J.J.; van Achterberg, T.; Draijer, N.

    2014-01-01

    For patients with comorbid complex posttraumatic stress disorder (PTSD) and psychotic disorder, trauma-focused therapy may be difficult to endure. Phase-based treatment including (a) stabilization, (b) trauma-focused therapy, and (c) integration of personality with recovery of connection appears to

  2. The challenge for genetic epidemiologists: how to analyze large numbers of SNPs in relation to complex diseases.

    Science.gov (United States)

    Heidema, A Geert; Boer, Jolanda M A; Nagelkerke, Nico; Mariman, Edwin C M; van der A, Daphne L; Feskens, Edith J M

    2006-04-21

    Genetic epidemiologists have taken the challenge to identify genetic polymorphisms involved in the development of diseases. Many have collected data on large numbers of genetic markers but are not familiar with available methods to assess their association with complex diseases. Statistical methods have been developed for analyzing the relation between large numbers of genetic and environmental predictors to disease or disease-related variables in genetic association studies. In this commentary we discuss logistic regression analysis, neural networks, including the parameter decreasing method (PDM) and genetic programming optimized neural networks (GPNN) and several non-parametric methods, which include the set association approach, combinatorial partitioning method (CPM), restricted partitioning method (RPM), multifactor dimensionality reduction (MDR) method and the random forests approach. The relative strengths and weaknesses of these methods are highlighted. Logistic regression and neural networks can handle only a limited number of predictor variables, depending on the number of observations in the dataset. Therefore, they are less useful than the non-parametric methods to approach association studies with large numbers of predictor variables. GPNN on the other hand may be a useful approach to select and model important predictors, but its performance to select the important effects in the presence of large numbers of predictors needs to be examined. Both the set association approach and random forests approach are able to handle a large number of predictors and are useful in reducing these predictors to a subset of predictors with an important contribution to disease. The combinatorial methods give more insight in combination patterns for sets of genetic and/or environmental predictor variables that may be related to the outcome variable. As the non-parametric methods have different strengths and weaknesses we conclude that to approach genetic association

  3. Learning from Nature - Mapping of Complex Hydrological and Geomorphological Process Systems for More Realistic Modelling of Hazard-related Maps

    Science.gov (United States)

    Chifflard, Peter; Tilch, Nils

    2010-05-01

    Introduction Hydrological or geomorphological processes in nature are often very diverse and complex. This is partly due to the regional characteristics which vary over time and space, as well as changeable process-initiating and -controlling factors. Despite being aware of this complexity, such aspects are usually neglected in the modelling of hazard-related maps due to several reasons. But particularly when it comes to creating more realistic maps, this would be an essential component to consider. The first important step towards solving this problem would be to collect data relating to regional conditions which vary over time and geographical location, along with indicators of complex processes. Data should be acquired promptly during and after events, and subsequently digitally combined and analysed. Study area In June 2009, considerable damage occurred in the residential area of Klingfurth (Lower Austria) as a result of great pre-event wetness and repeatedly heavy rainfall, leading to flooding, debris flow deposit and gravitational mass movement. One of the causes is the fact that the meso-scale watershed (16 km²) of the Klingfurth stream is characterised by adverse geological and hydrological conditions. Additionally, the river system network with its discharge concentration within the residential zone contributes considerably to flooding, particularly during excessive rainfall across the entire region, as the flood peaks from different parts of the catchment area are superposed. First results of mapping Hydro(geo)logical surveys across the entire catchment area have shown that - over 600 gravitational mass movements of various type and stage have occurred. 516 of those have acted as a bed load source, while 325 mass movements had not reached the final stage yet and could thus supply bed load in the future. It should be noted that large mass movements in the initial or intermediate stage were predominately found in clayey-silty areas and weathered material

  4. Population Dynamics Among six Major Groups of the Oryza rufipogon Species Complex, Wild Relative of Cultivated Asian Rice.

    Science.gov (United States)

    Kim, HyunJung; Jung, Janelle; Singh, Namrata; Greenberg, Anthony; Doyle, Jeff J; Tyagi, Wricha; Chung, Jong-Wook; Kimball, Jennifer; Hamilton, Ruaraidh Sackville; McCouch, Susan R

    2016-12-01

    Understanding population structure of the wild progenitor of Asian cultivated rice (O. sativa), the Oryza rufipogon species complex (ORSC), is of interest to plant breeders and contributes to our understanding of rice domestication. A collection of 286 diverse ORSC accessions was evaluated for nuclear variation using genotyping-by-sequencing (113,739 SNPs) and for chloroplast variation using Sanger sequencing (25 polymorphic sites). Six wild subpopulations were identified, with 25 % of accessions classified as admixed. Three of the wild groups were genetically and geographically closely related to the O. sativa subpopulations, indica, aus and japonica, and carried O. sativa introgressions; the other three wild groups were genetically divergent, had unique chloroplast haplotypes, and were located at the geographical extremes of the species range. The genetic subpopulations were significantly correlated (r 2  = 0.562) with traditional species designations, O. rufipogon (perennial) and O. nivara (annual), differentiated based on morphology and life history. A wild diversity panel of 95 purified (inbred) accessions was developed for future genetic studies. Our results suggest that the cultivated aus subpopulation is most closely related to an annual wild relative, japonica to a perennial wild relative, and indica to an admixed population of diverse annual and perennial wild ancestors. Gene flow between ORSC and O. sativa is common in regions where rice is cultivated, threatening the identity and diversity of wild ORSC populations. The three geographically isolated ORSC populations harbor variation rarely seen in cultivated rice and provide a unique window into the genetic composition of ancient rice subpopulations.

  5. Indoor environmental and air quality characteristics, building-related health symptoms, and worker productivity in a federal government building complex.

    Science.gov (United States)

    Lukcso, David; Guidotti, Tee Lamont; Franklin, Donald E; Burt, Allan

    2016-01-01

    Building Health Sciences, Inc. (BHS), investigated environmental conditions by many modalities in 71 discreet areas of 12 buildings in a government building complex that had experienced persistent occupant complaints despite correction of deficiencies following a prior survey. An online health survey was completed by 7,637 building occupants (49% response rate), a subset of whom voluntarily wore personal sampling apparatus and underwent medical evaluation. Building environmental measures were within current standards and guidelines, with few outliers. Four environmental factors were consistently associated with group-level building-related health complaints: physical comfort/discomfort, odor, job stress, and glare. Several other factors were frequently commented on by participants, including cleanliness, renovation and construction activities, and noise. Low relative humidity was significantly associated with lower respiratory and "sick building syndrome"-type symptoms. No other environmental conditions (including formaldehyde, PM10 [particulate matter with an aerodynamic diameter work but at reduced capacity), and increase in reported symptom-days, including symptoms not related to respiratory disease. We found that in buildings without unusual hazards and with environmental and air quality indicators within the range of acceptable indoor air quality standards, there is an identifiable population of occupants with a high prevalence of asthma and allergic disease who disproportionately report discomfort and lost productivity due to symptoms and that in "normal" buildings these outcome indicators are more closely associated with host factors than with environmental conditions. We concluded from the experience of this study that building-related health complaints should be investigated at the work-area level and not at a building-wide level. An occupant-centric medical evaluation should guide environmental investigations, especially when screening results of building

  6. Clinical Phenomenology of Childhood Abuse-Related Complex PTSD in a Population of Female Patients: Patterns of Personality Disturbance

    NARCIS (Netherlands)

    Dorrepaal, E.; Thomaes, K.; Smit, J.H.; Hoogendoorn, A.; Veltman, D.J.; van Balkom, A.J.L.M.; Draijer, P.J.

    2012-01-01

    Objective: Complex posttraumatic stress disorder (PTSD) involves a variety of personality disturbances presumed to result from repeated interpersonal trauma such as child abuse. As Complex PTSD patients are a heterogeneous population, we searched for clinically relevant personality-based subtypes.

  7. Tandem Extraction/Liquid Chromatography-Mass Spectrometry Protocol for the Analysis of Acrylamide and Surfactant-related Compounds in Complex Aqueous Environmental Samples

    Science.gov (United States)

    The development of a liquid chromatography‐mass spectrometry (LC‐MS)‐based strategy for the detection and quantitation of acrylamide and surfactant‐related compounds in aqueous complex environmental samples.

  8. From control to causation: Validating a 'complex systems model' of running-related injury development and prevention.

    Science.gov (United States)

    Hulme, A; Salmon, P M; Nielsen, R O; Read, G J M; Finch, C F

    2017-11-01

    There is a need for an ecological and complex systems approach for better understanding the development and prevention of running-related injury (RRI). In a previous article, we proposed a prototype model of the Australian recreational distance running system which was based on the Systems Theoretic Accident Mapping and Processes (STAMP) method. That model included the influence of political, organisational, managerial, and sociocultural determinants alongside individual-level factors in relation to RRI development. The purpose of this study was to validate that prototype model by drawing on the expertise of both systems thinking and distance running experts. This study used a modified Delphi technique involving a series of online surveys (December 2016- March 2017). The initial survey was divided into four sections containing a total of seven questions pertaining to different features associated with the prototype model. Consensus in opinion about the validity of the prototype model was reached when the number of experts who agreed or disagreed with survey statement was ≥75% of the total number of respondents. A total of two Delphi rounds was needed to validate the prototype model. Out of a total of 51 experts who were initially contacted, 50.9% (n = 26) completed the first round of the Delphi, and 92.3% (n = 24) of those in the first round participated in the second. Most of the 24 full participants considered themselves to be a running expert (66.7%), and approximately a third indicated their expertise as a systems thinker (33.3%). After the second round, 91.7% of the experts agreed that the prototype model was a valid description of the Australian distance running system. This is the first study to formally examine the development and prevention of RRI from an ecological and complex systems perspective. The validated model of the Australian distance running system facilitates theoretical advancement in terms of identifying practical system

  9. Relating catalytic activity and electrochemical properties: The case of arene-ruthenium phenanthroline complexes catalytically active in transfer hydrogenation

    Czech Academy of Sciences Publication Activity Database

    Štěpnička, P.; Ludvík, Jiří; Canivet, J.; Süss-Fink, G.

    2006-01-01

    Roč. 359, č. 8 (2006), s. 2369-2374 ISSN 0020-1693 R&D Projects: GA AV ČR IAA4040304 Institutional research plan: CEZ:AV0Z40400503 Keywords : arene complexes * chloro complexes * aqua complexes Subject RIV: CG - Electrochemistry Impact factor: 1.674, year: 2006

  10. Comprehension and utilisation of pointing gestures and gazing in dog-human communication in relatively complex situations.

    Science.gov (United States)

    Lakatos, Gabriella; Gácsi, Márta; Topál, József; Miklósi, Adám

    2012-03-01

    The aim of the present investigation was to study the visual communication between humans and dogs in relatively complex situations. In the present research, we have modelled more lifelike situations in contrast to previous studies which often relied on using only two potential hiding locations and direct association between the communicative signal and the signalled object. In Study 1, we have provided the dogs with four potential hiding locations, two on each side of the experimenter to see whether dogs are able to choose the correct location based on the pointing gesture. In Study 2, dogs had to rely on a sequence of pointing gestures displayed by two different experimenters. We have investigated whether dogs are able to recognise an 'indirect signal', that is, a pointing toward a pointer. In Study 3, we have examined whether dogs can understand indirect information about a hidden object and direct the owner to the particular location. Study 1 has revealed that dogs are unlikely to rely on extrapolating precise linear vectors along the pointing arm when relying on human pointing gestures. Instead, they rely on a simple rule of following the side of the human gesturing. If there were more targets on the same side of the human, they showed a preference for the targets closer to the human. Study 2 has shown that dogs are able to rely on indirect pointing gestures but the individual performances suggest that this skill may be restricted to a certain level of complexity. In Study 3, we have found that dogs are able to localise the hidden object by utilising indirect human signals, and they are able to convey this information to their owner.

  11. Regional-dependent intestinal permeability and BCS classification: elucidation of pH-related complexity in rats using pseudoephedrine.

    Science.gov (United States)

    Fairstein, Moran; Swissa, Rotem; Dahan, Arik

    2013-04-01

    Based on its lower Log P value relative to metoprolol, a marker for the low/high-permeability (P(eff)) class boundary, pseudoephedrine was provisionally classified as BCS low-permeability compound. On the other hand, following oral administration, pseudoephedrine fraction dose absorbed (F(abs)) and systemic bioavailability approaches 100%. This represents a challenge to the generally recognized P(eff)-F(abs) correlation. The purpose of this study was to elucidate the underlying mechanisms behind the confusion in pseudoephedrine's BCS classification. Pseudoephedrine's BCS solubility class was determined, and its physicochemical properties and intestinal permeability were thoroughly investigated, both in vitro and in vivo in rats, considering the complexity of the whole of the small intestine. Pseudoephedrine was found to be unequivocally a high-solubility compound. All of the permeability studies revealed similar phenomenon; at any given intestinal segment/pH, the permeability of metoprolol was higher than that of pseudoephedrine, however, as the intestinal region becomes progressively distal, and the pH gradually increases, pseudoephedrine's permeability rises above that of metoprolol in the former segment. This unique permeability pattern likely explains pseudoephedrine's complete absorption. In conclusion, pseudoephedrine is a BCS Class I compound; no discrepancy between P(eff) and F(abs) is involved in its absorption. Rather, it reflects the complexity behind P(eff) when considering the whole of the intestine. We propose to allow high-permeability classification to drugs with P(eff) that matches/exceeds the low/high class benchmark anywhere throughout the intestinal tract and not restricted necessarily to the jejunum.

  12. Estimating the Permittivity of Rogers 4003C Substrate at Low Frequencies for Application in a Superdirective First-Order Probe for SNF Measurements

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.

    2016-01-01

    The bulk permittivity of Rogers 4003C substrate is estimated in the lower UHF frequency band by comparing the simulated and measured return loss for a bandpass filter based on a coplanar waveguide and a capacitively loaded loop. The obtained value, which deviates from that specified by Rogers at ...... GHz, is subsequently utilized for accurate design of a new light-weight superdirective first-order probe for spherical near-field (SNF) antenna measurements at low frequencies.......The bulk permittivity of Rogers 4003C substrate is estimated in the lower UHF frequency band by comparing the simulated and measured return loss for a bandpass filter based on a coplanar waveguide and a capacitively loaded loop. The obtained value, which deviates from that specified by Rogers at 10...

  13. Unilateral vestibular deafferentation-induced changes in calcium signaling-related molecules in the rat vestibular nuclear complex.

    Science.gov (United States)

    Masumura, Chisako; Horii, Arata; Mitani, Kenji; Kitahara, Tadashi; Uno, Atsuhiko; Kubo, Takeshi

    2007-03-23

    Inquiries into the neurochemical mechanisms of vestibular compensation, a model of lesion-induced neuronal plasticity, reveal the involvement of both voltage-gated Ca(2+) channels (VGCC) and intracellular Ca(2+) signaling. Indeed, our previous microarray analysis showed an up-regulation of some calcium signaling-related genes such as the alpha2 subunit of L-type calcium channels, calcineurin, and plasma membrane Ca(2+) ATPase 1 (PMCA1) in the ipsilateral vestibular nuclear complex (VNC) following unilateral vestibular deafferentation (UVD). To further elucidate the role of calcium signaling-related molecules in vestibular compensation, we used a quantitative real-time polymerase chain reaction (PCR) method to confirm the microarray results and investigated changes in expression of these molecules at various stages of compensation (6 h to 2 weeks after UVD). We also investigated the changes in gene expression during Bechterew's phenomenon and the effects of a calcineurin inhibitor on vestibular compensation. Real-time PCR showed that genes for the alpha2 subunit of VGCC, PMCA2, and calcineurin were transiently up-regulated 6 h after UVD in ipsilateral VNC. A subsequent UVD, which induced Bechterew's phenomenon, reproduced a complete mirror image of the changes in gene expressions of PMCA2 and calcineurin seen in the initial UVD, while the alpha2 subunit of VGCC gene had a trend to increase in VNC ipsilateral to the second lesion. Pre-treatment by FK506, a calcineurin inhibitor, decelerated the vestibular compensation in a dose-dependent manner. Although it is still uncertain whether these changes in gene expression are causally related to the molecular mechanisms of vestibular compensation, this observation suggests that after increasing the Ca(2+) influx into the ipsilateral VNC neurons via up-regulated VGCC, calcineurin may be involved in their synaptic plasticity. Conversely, an up-regulation of PMCA2, a brain-specific Ca(2+) pump, would increase an efflux of Ca

  14. Clinical significance of SNP (rs2596542 in histocompatibility complex class I-related gene A promoter region among hepatitis C virus related hepatocellular carcinoma cases

    Directory of Open Access Journals (Sweden)

    Amal A. Mohamed

    2017-07-01

    Full Text Available The major histocompatibility complex class I-related gene A (MICA is an antigen induced by stress and performs an integral role in immune responses as an anti-infectious and antitumor agent. This work was designed to investigate whether (SNP rs2596542C/T in MICA promoter region is predictive of liver cirrhosis (LC and hepatocellular carcinoma (HCC or not. Forty-seven healthy controls and 94 HCV-infected patients, subdivided into 47 LC and 47 HCC subjects were enrolled in this study. SNP association was studied using real time PCR and soluble serum MICA concentration was measured using ELISA. Results showed that heterozygous genotype rs2596542CT was significantly (P = 0.022 distributed between HCC and LC related CHC patients. The sMICA was significantly higher (P = 0.0001 among HCC and LC. No significant association (P = 0.56 between rs2596542CT genotypes and sMICA levels was observed. Studying SNP rs2596542C/T association with HCC and LC susceptibility revealed that statistical significant differences (P = 0.013, P = 0.027 were only observed between SNP rs2596542C/T and each of HCC and LC, respectively, versus healthy controls, indicating that the rs2596542C/T genetic variation is not a significant contributor to HCC development in LC patients. Moreover, the T allele was considered a risk factor for HCC and LC vulnerability in HCV patients (OR = 1.93 and 2.1, respectively, while the C allele contributes to decreasing HCC risk. Therefore, SNP (rs2596542C/T in MICA promoter region and sMICA levels might be potential useful markers in the assessment of liver disease progression to LC and HCC.

  15. Sample-size resonance, ferromagnetic resonance and magneto-permittivity resonance in multiferroic nano-BiFeO{sub 3}/paraffin composites at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lei; Li, Zhenyu; Jiang, Jia; An, Taiyu; Qin, Hongwei; Hu, Jifan, E-mail: hujf@sdu.edu.cn

    2017-01-01

    In the present work, we demonstrate that ferromagnetic resonance and magneto-permittivity resonance can be observed in appropriate microwave frequencies at room temperature for multiferroic nano-BiFeO{sub 3}/paraffin composite sample with an appropriate sample-thickness (such as 2 mm). Ferromagnetic resonance originates from the room-temperature weak ferromagnetism of nano-BiFeO{sub 3}. The observed magneto-permittivity resonance in multiferroic nano-BiFeO{sub 3} is connected with the dynamic magnetoelectric coupling through Dzyaloshinskii–Moriya (DM) magnetoelectric interaction or the combination of magnetostriction and piezoelectric effects. In addition, we experimentally observed the resonance of negative imaginary permeability for nano BiFeO{sub 3}/paraffin toroidal samples with longer sample thicknesses D=3.7 and 4.9 mm. Such resonance of negative imaginary permeability belongs to sample-size resonance. - Highlights: • Nano-BiFeO{sub 3}/paraffin composite shows a ferromagnetic resonance. • Nano-BiFeO{sub 3}/paraffin composite shows a magneto-permittivity resonance. • Resonance of negative imaginary permeability in BiFeO{sub 3} is a sample-size resonance. • Nano-BiFeO{sub 3}/paraffin composite with large thickness shows a sample-size resonance.

  16. Sample-size resonance, ferromagnetic resonance and magneto-permittivity resonance in multiferroic nano-BiFeO3/paraffin composites at room temperature

    International Nuclear Information System (INIS)

    Wang, Lei; Li, Zhenyu; Jiang, Jia; An, Taiyu; Qin, Hongwei; Hu, Jifan

    2017-01-01

    In the present work, we demonstrate that ferromagnetic resonance and magneto-permittivity resonance can be observed in appropriate microwave frequencies at room temperature for multiferroic nano-BiFeO 3 /paraffin composite sample with an appropriate sample-thickness (such as 2 mm). Ferromagnetic resonance originates from the room-temperature weak ferromagnetism of nano-BiFeO 3 . The observed magneto-permittivity resonance in multiferroic nano-BiFeO 3 is connected with the dynamic magnetoelectric coupling through Dzyaloshinskii–Moriya (DM) magnetoelectric interaction or the combination of magnetostriction and piezoelectric effects. In addition, we experimentally observed the resonance of negative imaginary permeability for nano BiFeO 3 /paraffin toroidal samples with longer sample thicknesses D=3.7 and 4.9 mm. Such resonance of negative imaginary permeability belongs to sample-size resonance. - Highlights: • Nano-BiFeO 3 /paraffin composite shows a ferromagnetic resonance. • Nano-BiFeO 3 /paraffin composite shows a magneto-permittivity resonance. • Resonance of negative imaginary permeability in BiFeO 3 is a sample-size resonance. • Nano-BiFeO 3 /paraffin composite with large thickness shows a sample-size resonance.

  17. The effects of complex exercise on shoulder range of motion and pain for women with breast cancer-related lymphedema: a single-blind, randomized controlled trial.

    Science.gov (United States)

    Park, Jin-Hyuck

    2017-07-01

    This study was to investigate the effects of complex exercise on shoulder range of motion and pain for women with breast cancer-related lymphedema. 69 women participated in this study and then they were randomly allocated to complex exercise group (n = 35) or the conventional decongestive therapy group (n = 34). All subjects received 8 sessions for 4 weeks. To identify the effects on shoulder range of motion and pain, goniometer and visual analog scale were used, respectively. The outcome measurements were performed before and after the 4 week intervention. After 4 weeks, complex exercise group had greater improvements in shoulder range of motion and pain compared with the conventional decongestive therapy group (p women with breast cancer-related lymphedema. Complex exercise would be useful to improve shoulder range of motion and pain of the women with breast cancer-related lymphedema.

  18. The relation between the column density structures and the magnetic field orientation in the Vela C molecular complex

    Science.gov (United States)

    Soler, J. D.; Ade, P. A. R.; Angilè, F. E.; Ashton, P.; Benton, S. J.; Devlin, M. J.; Dober, B.; Fissel, L. M.; Fukui, Y.; Galitzki, N.; Gandilo, N. N.; Hennebelle, P.; Klein, J.; Li, Z.-Y.; Korotkov, A. L.; Martin, P. G.; Matthews, T. G.; Moncelsi, L.; Netterfield, C. B.; Novak, G.; Pascale, E.; Poidevin, F.; Santos, F. P.; Savini, G.; Scott, D.; Shariff, J. A.; Thomas, N. E.; Tucker, C. E.; Tucker, G. S.; Ward-Thompson, D.

    2017-07-01

    We statistically evaluated the relative orientation between gas column density structures, inferred from Herschel submillimetre observations, and the magnetic field projected on the plane of sky, inferred from polarized thermal emission of Galactic dust observed by the Balloon-borne Large-Aperture Submillimetre Telescope for Polarimetry (BLASTPol) at 250, 350, and 500 μm, towards the Vela C molecular complex. First, we find very good agreement between the polarization orientations in the three wavelength-bands, suggesting that, at the considered common angular resolution of 3.´0 that corresponds to a physical scale of approximately 0.61 pc, the inferred magnetic field orientation is not significantly affected by temperature or dust grain alignment effects. Second, we find that the relative orientation between gas column density structures and the magnetic field changes progressively with increasing gas column density, from mostly parallel or having no preferred orientation at low column densities to mostly perpendicular at the highest column densities. This observation is in agreement with previous studies by the Planck collaboration towards more nearby molecular clouds. Finally, we find a correspondencebetween (a) the trends in relative orientation between the column density structures and the projected magnetic field; and (b) the shape of the column density probability distribution functions (PDFs). In the sub-regions of Vela C dominated by one clear filamentary structure, or "ridges", where the high-column density tails of the PDFs are flatter, we find a sharp transition from preferentially parallel or having no preferred relative orientation at low column densities to preferentially perpendicular at highest column densities. In the sub-regions of Vela C dominated by several filamentary structures with multiple orientations, or "nests", where the maximum values of the column density are smaller than in the ridge-like sub-regions and the high-column density

  19. Development of the mechanical engineering complex on the basis of the improvement of large and small businesses relations

    Directory of Open Access Journals (Sweden)

    Sokolova Svetlana

    2017-01-01

    Full Text Available Condition, pace and character of the development of the mechanical engineering complex is in many aspects a crucial factor for the social and economic situation of any country. The development of market relations, changes of the conditions of doing business encourage the enterprises to search new managerial methods and to improve the interaction forms. In this respect the display of the peculiarities of the interaction of large machine engineering enterprises and small business in this sphere and also the assessment of the relationship of their development is an important and crucial issue under modern conditions. The most widely spread forms of the cooperation of large scale mechanical engineering enterprises and small businesses of the industry are: outsourcing, franchising, leasing, subcontracting, venture financing, creation of regional forms of the cooperation of large and small firms. However cooperation processes of large scale and small entrepreneurship in Russia are not properly developed. The authors determine the factors hindering the growth of the machine building industry, suggest the recommendations for the development of the large scale enterprises and small business in the industry, substantiate the role of the government in this process. Besides the mechanism of the state support of the development of small business is described.

  20. Neurexin-Neuroligin Synaptic Complex Regulates Schizophrenia-Related DISC1/Kal-7/Rac1 “Signalosome”

    DEFF Research Database (Denmark)

    Jacobsen, Sylwia Owczarek; Bang, Marie Louise; Berezin, Vladimir

    2015-01-01

    Neurexins (NXs) and neuroligins (NLs) are cell adhesion molecules that are localized at opposite sites of synaptic membranes. They interact with each other to promote the assembly, maintenance, and function of synapses in the central nervous system. Both NX and NL are cleaved from a membrane......-attached intracellular domain in an activity-dependent manner, generating the soluble ectodomain of NX or NL. Expression of the NX1 and NX3 genes in the brain appears to be regulated by a schizophrenia-related protein, DISC1. Here, we show that soluble ecto-NX1β can regulate the expression of DISC1 and induce signaling...... downstream of DISC1. We also show that NL1 binds to a well-characterized DISC1 interaction partner, Kal-7, and this interaction can be compromised by DISC1. Our results indicate that the NX/NL synaptic complex is intrinsically involved in the regulation of DISC1 function, thus contributing to a better...

  1. Child abuse and neglect in complex dissociative disorder, abuse-related chronic PTSD, and mixed psychiatric samples.

    Science.gov (United States)

    Dorahy, Martin J; Middleton, Warwick; Seager, Lenaire; Williams, Mary; Chambers, Ron

    2016-01-01

    Only a select number of studies have examined different forms of child maltreatment in complex dissociative disorders (DDs) in comparison to other groups. Few of these have used child abuse-related chronic posttraumatic stress disorder (C-PTSD) and mixed psychiatric (MP) patients with maltreatment as comparison groups. This study examined child sexual, physical, and emotional abuse as well as physical and emotional neglect in DD (n = 39), C-PTSD (n = 13), and MP (n = 21) samples, all with abuse and neglect histories. The predictive capacity of these different forms of maltreatment across the 3 groups was assessed for pathological dissociation, shame, guilt, relationship esteem, relationship anxiety, relationship depression, and fear of relationships. All forms of maltreatment differentiated the DD from the MP group, and sexual abuse differentiated the DD sample from the C-PTSD group. Childhood sexual abuse was the only predictor of pathological dissociation. Emotional abuse predicted shame, guilt, relationship anxiety, and fear of relationships. Emotional neglect predicted relationship anxiety and relationship depression. Physical neglect was associated with less relationship anxiety. Different forms of abuse and neglect are associated with different symptom clusters in psychiatric patients with maltreatment histories.

  2. Species from within the Phytophthora cryptogea complex and related species, P. erythroseptica and P. sansomeana, readily hybridize.

    Science.gov (United States)

    Safaiefarahani, Banafsheh; Mostowfizadeh-Ghalamfarsa, Reza; Hardy, Giles E St J; Burgess, Treena I

    2016-08-01

    During a study on the phylogenetic relationships between species in the Phytophthora cryptogea complex and related species, Phytophthora erythroseptica and Phytophthora sansomeana, 19 hybrid isolates with multiple polymorphisms in the nuclear sequences were observed. Molecular characterization of hybrids was achieved by sequencing three nuclear (internal transcribed spacers, β-tubulin (TUB), heat shock protein 90) and two mitochondrial (cytochrome c oxidase subunit I (coxI), NADH dehydrogenase subunit I (NADH)) gene regions and cloning of the single-copy nuclear gene, TUB. Based on the molecular studies the hybrid isolates belonged to six distinct groups between P. cryptogea, P. erythroseptica, Phytophthora pseudocryptogea, P. sansomeana, and Phytophthora sp. kelmania. In all cases, only a single coxI and NADH allele was detected and nuclear genes were biparentally inherited, suggesting that the hybrids arose from sexual recombination events. Colony morphology, growth rate, cardinal temperatures, breeding system, and morphology of sporangia, oogonia, oospores, and antheridia were also determined. Some morphological differences between the hybrids and the parental species were noted; however, they were not sufficient to reliably distinguish the taxa and DNA markers from nuclear and mitochondrial genes will to be necessary for their identification. The parental species are all important pathogens of agricultural fields that have been transported globally. With the apparent ease of hybridization within this group there is ample opportunity for virulent hybrids to form, perhaps with extended host ranges. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  3. Relative importance of local habitat complexity and regional factors for assemblages of oribatid mites (Acari: Oribatida) in Sphagnum peat bogs.

    Science.gov (United States)

    Minor, M A; Ermilov, S G; Philippov, D A; Prokin, A A

    2016-11-01

    We investigated communities of oribatid mites in five peat bogs in the north-west of the East European plain. We aimed to determine the extent to which geographic factors (latitude, separation distance), local environment (Sphagnum moss species, ground water level, biogeochemistry) and local habitat complexity (diversity of vascular plants and bryophytes in the surrounding plant community) influence diversity and community composition of Oribatida. There was a significant north-to-south increase in Oribatida abundance. In the variance partitioning, spatial factors explained 33.1 % of variability in abundance across samples; none of the environmental factors were significant. Across all bogs, Oribatida species richness and community composition were similar in Sphagnum rubellum and Sphagnum magellanicum, but significantly different and less diverse in Sphagnum cuspidatum. Sphagnum microhabitat explained 52.2 % of variability in Oribatida species richness, whereas spatial variables explained only 8.7 %. There was no distance decay in community similarity between bogs with increased geographical distance. The environmental variables explained 34.9 % of the variance in community structure, with vascular plants diversity, bryophytes diversity, and ground water level all contributing significantly; spatial variables explained 15.1 % of the total variance. Overall, only 50 % of the Oribatida community variance was explained by the spatial structure and environmental variables. We discuss relative importance of spatial and local environmental factors, and make general inferences about the formation of fauna in Sphagnum bogs.

  4. Zeaxanthin binds to light-harvesting complex stress-related protein to enhance nonphotochemical quenching in Physcomitrella patens.

    Science.gov (United States)

    Pinnola, Alberta; Dall'Osto, Luca; Gerotto, Caterina; Morosinotto, Tomas; Bassi, Roberto; Alboresi, Alessandro

    2013-09-01

    Nonphotochemical quenching (NPQ) dissipates excess energy to protect the photosynthetic apparatus from excess light. The moss Physcomitrella patens exhibits strong NPQ by both algal-type light-harvesting complex stress-related (LHCSR)-dependent and plant-type S subunit of Photosystem II (PSBS)-dependent mechanisms. In this work, we studied the dependence of NPQ reactions on zeaxanthin, which is synthesized under light stress by violaxanthin deepoxidase (VDE) from preexisting violaxanthin. We produced vde knockout (KO) plants and showed they underwent a dramatic reduction in thermal dissipation ability and enhanced photoinhibition in excess light conditions. Multiple mutants (vde lhcsr KO and vde psbs KO) showed that zeaxanthin had a major influence on LHCSR-dependent NPQ, in contrast with previous reports in Chlamydomonas reinhardtii. The PSBS-dependent component of quenching was less dependent on zeaxanthin, despite the near-complete violaxanthin to zeaxanthin exchange in LHC proteins. Consistent with this, we provide biochemical evidence that native LHCSR protein binds zeaxanthin upon excess light stress. These findings suggest that zeaxanthin played an important role in the adaptation of modern plants to the enhanced levels of oxygen and excess light intensity of land environments.

  5. Zeaxanthin Binds to Light-Harvesting Complex Stress-Related Protein to Enhance Nonphotochemical Quenching in Physcomitrella patens[W

    Science.gov (United States)

    Pinnola, Alberta; Dall’Osto, Luca; Gerotto, Caterina; Morosinotto, Tomas; Bassi, Roberto; Alboresi, Alessandro

    2013-01-01

    Nonphotochemical quenching (NPQ) dissipates excess energy to protect the photosynthetic apparatus from excess light. The moss Physcomitrella patens exhibits strong NPQ by both algal-type light-harvesting complex stress-related (LHCSR)–dependent and plant-type S subunit of Photosystem II (PSBS)-dependent mechanisms. In this work, we studied the dependence of NPQ reactions on zeaxanthin, which is synthesized under light stress by violaxanthin deepoxidase (VDE) from preexisting violaxanthin. We produced vde knockout (KO) plants and showed they underwent a dramatic reduction in thermal dissipation ability and enhanced photoinhibition in excess light conditions. Multiple mutants (vde lhcsr KO and vde psbs KO) showed that zeaxanthin had a major influence on LHCSR-dependent NPQ, in contrast with previous reports in Chlamydomonas reinhardtii. The PSBS-dependent component of quenching was less dependent on zeaxanthin, despite the near-complete violaxanthin to zeaxanthin exchange in LHC proteins. Consistent with this, we provide biochemical evidence that native LHCSR protein binds zeaxanthin upon excess light stress. These findings suggest that zeaxanthin played an important role in the adaptation of modern plants to the enhanced levels of oxygen and excess light intensity of land environments. PMID:24014548

  6. Macular ganglion cell complex and retinal nerve fiber layer comparison in different stages of age-related macular degeneration.

    Science.gov (United States)

    Zucchiatti, Ilaria; Parodi, Maurizio Battaglia; Pierro, Luisa; Cicinelli, Maria Vittoria; Gagliardi, Marco; Castellino, Niccolò; Bandello, Francesco

    2015-09-01

    To employ optical coherence tomography (OCT) to analyze the morphologic changes in the inner retina in different categories of age-related macular degeneration (AMD). Observational cross-sectional study. Single-center study. Inclusion criteria were age over 50, diagnosis of Age-Related Eye Disease Study (AREDS) category 2 and 3, naïve neovascular AMD, and atrophic AMD. Healthy patients of similar age acted as a control group. Primary outcome measures were the changes in ganglion cell complex (GCC) and retinal nerve fiber layer (RNFL). Secondary outcomes included modifications of rim area and cup-to-disc ratio. One hundred and thirty eyes of 130 patients were recruited: 26 eyes for AREDS category 2, 26 for AREDS category 3, 26 for neovascular AMD, 26 with atrophic AMD, and 26 controls. Mean peripapillary RNFL thickness was significantly lower in neovascular AMD, compared to controls (P = .004); peripapillary RNFL did not significantly vary among AREDS category 2 and 3 and atrophic AMD groups, compared to controls. Mean GCC thickness was higher in the control group, becoming progressively thinner up to neovascular and atrophic AMD groups (P < .0001). Rim area was significantly thinner in the neovascular AMD group compared with controls (P = .047); cup-to-disc ratio was higher in the neovascular AMD group compared with the control group (P = .047). This study demonstrates that eyes with neovascular AMD display reduced RNFL and GCC thickness. RNFL is partially spared in atrophic advanced AMD. The identification of alteration in RNFL and GCC thickness may reveal useful for future therapeutic implications. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Dispersion of dielectric permittivity and magnetic properties of solid solution PZT–PFT

    Directory of Open Access Journals (Sweden)

    Skulski Ryszard

    2015-09-01

    Full Text Available In this paper we present the results of investigations into ceramic samples of solid solution (1-x(PbZr0.53Ti0.47O3- x(PbFe0.5Ta0.503 (i.e. (1-xPZT-xPFT with x = 0.25, 0.35 and 0.45. We try to find the relation between the character of dielectric dispersion at various temperatures and the composition of this solution. We also describe the magnetic properties of investigated samples. With increasing the content of PFT also mass magnetization and mass susceptibility increase (i.e. magnetic properties are more pronounced at every temperature. The temperature dependences of mass magnetization and re­ciprocal of mass susceptibility have similar runs for all the compositions. However, our magnetic investigations exhibit weak antiferromagnetic ordering instead of the ferromagnetic one at room temperature. We can also say that up to room tempera­ture any magnetic phase transition has not occurred. It may be a result of the conditions of the technological process during producing our PZT-PFT ceramics.

  8. Acetylcholinesterase complexed with bivalent ligands related to huperzine a: experimental evidence for species-dependent protein-ligand complementarity.

    Science.gov (United States)

    Wong, Dawn M; Greenblatt, Harry M; Dvir, Hay; Carlier, Paul R; Han, Yi-Fan; Pang, Yuan-Ping; Silman, Israel; Sussman, Joel L

    2003-01-15

    Acetylcholinesterase (AChE) inhibitors improve the cognitive abilities of Alzheimer patients. (-)-Huperzine A [(-)-HupA], an alkaloid isolated from the club moss, Huperzia serrata, is one such inhibitor, but the search for more potent and selective drugs continues. Recently, alkylene-linked dimers of 5-amino-5,6,7,8-tetrahydroquinolinone (hupyridone, 1a), a fragment of HupA, were shown to serve as more potent inhibitors of AChE than (-)-HupA and monomeric 1a. We soaked two such dimers, (S,S)-(-)-bis(10)-hupyridone [(S,S)-(-)-2a] and (S,S)-(-)-bis(12)-hupyridone [(S,S)-(-)-2b] containing, respectively, 10 and 12 methylenes in the spacer, into trigonal TcAChE crystals, and solved the X-ray structures of the resulting complexes using the difference Fourier technique, both to 2.15 A resolution. The structures revealed one HupA-like 1a unit bound to the "anionic" subsite of the active-site, near the bottom of the active-site gorge, adjacent to Trp84, as seen for the TcAChE/(-)-HupA complex, and the second 1a unit near Trp279 in the "peripheral" anionic site at the top of the gorge, both bivalent molecules thus spanning the active-site gorge. The results confirm that the increased affinity of the dimeric HupA analogues for AChE is conferred by binding to the two "anionic" sites of the enzyme. Inhibition data show that (-)-2a binds to TcAChE approximately 6-7- and > 170-fold more tightly than (-)-2b and (-)-HupA, respectively. In contrast, previous data for rat AChE show that (-)-2b binds approximately 3- and approximately 2-fold more tightly than (-)-2a and (-)-HupA, respectively. Structural comparison of TcAChE with rat AChE, as represented by the closely related mouse AChE structure (1maa.pdb), reveals a narrower gorge for rat AChE, a perpendicular alignment of the Tyr337 ring to the gorge axis, and its conformational rigidity, as a result of hydrogen bonding between its hydroxyl group and that of Tyr341, relative to TcAChE Phe330. These structural differences in the

  9. Laboratory polarization and permittivity measurements to interpret dust polarimetric observations and in-situ radar studies. Significance for Rosetta mission at 67P/Churyumov-Gerasimenko

    Science.gov (United States)

    Levasseur-Regourd, Anny-Chantal; Brouet, Yann; Hadamcik, Edith; Heggy, Essam; Hines, Dean; Lasue, Jérémie; Renard, Jean-Baptiste

    2015-08-01

    Polarimetric astronomical observations on dust clouds and regolithic surfaces require laboratory simulations on samples to provide information on properties (size distribution, porosity, refractive index) of the scattering media. Similarly, in-situ radar investigations in the solar system require laboratory studies on samples to infer physical properties (e.g. porosity, ice/dust ratio) of sub-surfaces and interiors. Recent developments are illustrated with present studies related to the Rosetta mission, which begun its rendezvous with comet 67P/Churyumov-Gerasimeko (C-G) and landed the Philae module on its nucleus in 2014.We will summarize laboratory simulations with the PROGRA2 suite of instruments that study (in the visible to near IR domain) the polarimetric properties of dust samples in microgravity conditions or on surfaces [1], with emphasis on the interpretation of polarimetric observations of C-G, during its previous perihelion passages from Earth observatories, and currently from HST [2,3]. The presence of large dust particles in the pre-perihelion coma previously inferred from remote observations agrees with Rosetta ground truth [4]. We will also present measurements on the permittivity (in the millimeter to meter domain) of various dust samples, with emphasis on porous samples [5,6]. Results provide constraints on the properties of the subsurface and interior of C-G, as explored by MIRO on Rosetta and CONSERT on Philae.Such studies are relevant for the interpretation of polarimetric observations of other dust clouds (e.g. debris disks, interplanetary dust cloud, clouds in planetary atmospheres) and surfaces (e.g. planets, moons), as well as for those of other radar characterization studies (e.g. Mars, moons, asteroids).[1] Levasseur-Regourd et al. In Polarization of stars and planetary systems, Cambridge UP, in press 2015.[2] Hadamcik et al. A&A 517 2010.[3] Hines and Levasseur-Regourd, PSS submitted 2015.[4] Schulz et al. Nature 518 2015.[5] Heggy et al

  10. The relation between geometry, hydrology and stability of complex hillslopes examined using low-dimensional hydrological models

    NARCIS (Netherlands)

    Talebi, A.

    2008-01-01

    Key words: Hillslope geometry, Hillslope hydrology, Hillslope stability, Complex hillslopes, Modeling shallow landslides, HSB model, HSB-SM model.

    The hydrologic response of a hillslope to rainfall involves a complex, transient saturated-unsaturated interaction that usually leads to a

  11. Micro-oxygenation does not eliminate hydrogen sulfide and mercaptans from wine; it simply shifts redox and complex-related equilibria to reversible oxidized species and complexed forms.

    Science.gov (United States)

    Vela, Eduardo; Hernandez-Orte, Purificación; Franco-Luesma, Ernesto; Ferreira, Vicente

    2018-03-15

    This work seeks to assess the effects of micro-oxygenation (MOX) on the present and potential levels of Volatile Sulfur Compounds (VSCs) of wine. With such purpose, three red wines with a tendency to develop sulfury off-odors were subjected to three different MOX conditions (4.4-20mg/L delivered at 0.05 or 0.2mg/L/day). Samples were further subjected to Accelerated Reductive aging (AR) and analyzed for free and Brine Releasable (BR) VSCs and redox potential. Although MOX induced strong decreases in the levels of all free VSCs, hardly affected the ability of the wine to release back hydrogen sulfide and other mercaptans during AR-aging. During aging BR-levels of MOX samples became in most cases similar or higher than non-oxygenated controls. BR-levels and the fractions free/BR follow characteristic sigmoid plots when represented versus redox potential suggesting that all changes are the result of reversible equilibria between free, metal-complexed and oxidized forms of VSCs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Geochemical mass-balance to study the relative weathering rates of various formations in a complex watershed of lower Himalayas

    Science.gov (United States)

    Chattopadhyay, Pallavi; Kar, Swagat; Chouhan, Ramesh

    2017-04-01

    Weathering of rocks is a major process and believed to have the potential to alter Earth's surface. Aglar, a watershed in Garhwal Lesser Himalayas is identified and various formations of this complex geology are studied to understand the weathering process. A stream passes through the fault that divides the watershed into two slopes which have different lithotectonic units. Paligar and Belgar are the two main tributaries of Aglar stream flowing along the slopes respectively and joining at the valley near Thatyur village, India. Rocks like quartzite and limestone are generally hard, massive and resistant to weathering. However, sedimentary rocks are vulnerable to weathering and erosion. On the other hand, phyllites and schists are characterized by flaky minerals which weather quickly and promote instability . Aglar has all of them. The weathering processes are studied first using the hydrochemistry of Aglar river through major cations (Ca2+, Mg2+, Na+, K+) and major anions (SO42-, HCO-3, Cl-, NO3-). The discharges at various sampling points are calculated using area - velocity method. The basic idea in describing the discharge of material in a river is to estimate the mass of the substances transported through a cross section of the river per second. Dominance of Ca2+, Mg2+ and HCO-3 indicates that carbonate weathering is the major chemical weathering process near Belgar river. Paligar river has lower conductivity values compared to Belgar river which illustrates lower ionic concentrations. Mass-balance calculations are found often skewed and suggest the role of subsurface groundwater flow to explain the uncharacterized load. Southern side of the watershed with higher percentage of forest cover is found to have higher chemical weathering rates compared to the other slope having relatively lesser vegetation. These higher rates demonstrate the higher stream discharge load in that slope.

  13. Thermodynamic stability of complexes of BF3, PF5 and AsF5 with chlorine fluorides, oxyfluorides, and related compounds

    International Nuclear Information System (INIS)

    Trowbridge, L.D.

    1996-07-01

    The recent discovery of solid, water sensitive, arsenic-containing deposits in auxiliary process piping in the PGDP led to a search for explanations that could account for such accumulated material. A plausible explanation for the deposits is the formation of complexes of AsF 5 with one or more gases that may have been present as a result of cascade equipment cleanup activities. A literature search was performed. The target of the search was literature that would provide information on the dissociation pressure of complexes of AsF 5 or its hydrolysis products with any gases that may be (at least intermittently) present in the cascade location where the deposits were found. While the precise information sought (namely reliable, accurate dissociation pressures of such complexes at cascade temperatures) was not found in the detail desired. other information on these or similar complexes was obtained which permits prediction of the conditions under which the complexes might form, dissociate, or migrate, and how they might behave in the presence of atmospheric moisture. Information was gathered on potential AsF 5 complexes with ClF, ClF 3 , ClF 5 , ClF 3 O, ClO 2 F, and ClO 3 F. Information was also collected on many other related complexes as it was encountered, particularly for series of complexes which could assist in predicting chemical trends. Thermodynamic analysis and property estimation methods have been used to generate provisional estimates of the dissociation pressures of the two complexes ClF 3 *AsF 5 and ClO 2 F*AsF 5 . In addition, several hydrolysis species have been identified, and stability properties of the most relevant such complex (H 3 O*AsF 6 ) have similarly been estimated. While the predicted dissociation pressures are somewhat uncertain. they do lead to a tentative picture of the formation and behavior of such complexes in a cascade cleanup environment

  14. Catalytic ozonation not relying on hydroxyl radical oxidation: A selective and competitive reaction process related to metal-carboxylate complexes

    KAUST Repository

    Zhang, Tao; Croue, Jean-Philippe

    2014-01-01

    Catalytic ozonation following non-hydroxyl radical pathway is an important technique not only to degrade refractory carboxylic-containing organic compounds/matter but also to avoid catalyst deactivation caused by metal-carboxylate complexation

  15. Permittivity of polycrystalline material

    Czech Academy of Sciences Publication Activity Database

    Klíč, Antonín; Rychetský, Ivan

    2013-01-01

    Roč. 449, č. 1 (2013), s. 154-160 ISSN 0015-0193 R&D Projects: GA ČR GAP204/12/0232 Institutional support: RVO:68378271 Keywords : effective medium * polycrystal Subject RIV: BE - Theoretical Physics Impact factor: 0.383, year: 2013

  16. Communication complexity and information complexity

    Science.gov (United States)

    Pankratov, Denis

    Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

  17. Determination of stability constants of K and Cs nitrate complex with dicyclohexyl-18-crown-6 and dibenzo-18-crown-6 in isopropanol aqueous solutions

    International Nuclear Information System (INIS)

    Myasoedova, T.G.; Ponomareva, A.V.; Zagorets, P.A.; Filippov, E.A.

    1984-01-01

    Total stability constants of K and Cs nitrate complexes with dicyclohexyl-18-crown-6 and dibenzo-18-crown-6 in isopropanol aqueous solutions were determined by the method of low-frequency contact conductometry. Clearly defined K/Cs selectivity is observed for the system with dibenzo-18-crown-6. It is shown that lgβ depends on permittivity of the solvent. The decrease of permittivity of isopropanol aqueous solutions results in reduction of K/Cs selectivity of DB18C6

  18. Determination of stability constants of K and Cs nitrate complex with dicyclohexyl-18-crown-6 and dibenzo-18-crown-6 in isopropanol aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Myasoedova, T G; Ponomareva, A V; Zagorets, P A; Filippov, E A [Moskovskij Khimiko-Tekhnologicheskij Inst. (USSR)

    1984-08-01

    Total stability constants of K and Cs nitrate complexes with dicyclohexyl-18-crown-6 and dibenzo-18-crown-6 in isopropanol aqueous solutions were determined by the method of low-frequency contact conductometry. Clearly defined K/Cs selectivity is observed for the system with dibenzo-18-crown-6. It is shown that lg..beta.. depends on permittivity of the solvent. The decrease of permittivity of isopropanol aqueous solutions results in reduction of K/Cs selectivity of DB18C6.

  19. Geologic Mapping in Nogal Peak Quadrangle: Geochemistry, Intrusive Relations and Mineralization in the Sierra Blanca Igneous Complex, New Mexico

    Science.gov (United States)

    Goff, F.; Kelley, S. A.; Lawrence, J. R.; Cikowski, C. T.; Krier, D. J.; Goff, C. J.; McLemore, V. T.

    2011-12-01

    Nogal Peak quadrangle is located in the northern Sierra Blanca Igneous Complex (SBIC) and contains most of the White Mountain Wilderness (geologic map is available at http://geoinfo.nmt.edu/publications/maps/geologic/ofgm/details.cfml?Volume=134). The geology of the quad consists of a late Eocene to Oligocene volcanic pile (Sierra Blanca Volcanics, mostly alkali basalt to trachyte) intruded by a multitude of dikes, plugs and three stocks: Rialto, 31.4 Ma (mostly syenite), Three Rivers, ca. 29 to 27 Ma (quartz syenite intruded by subordinate alkali granite), and Bonito Lake, 26.6 Ma (mostly monzonite). Three Rivers stock is partially surrounded by alkali rhyolites that geochemically resemble the alkali granites. The circular shape of the stock and surrounding rhyolites suggests they form the root of a probable caldera. SBIC rocks have compositions typical of those found within the Rocky Mountain alkaline belt and those associated with continental rift zone magmatism. Because the volcanic host rocks are deeply eroded, intrusive relations with the stocks are well exposed. Most contacts at stock margins are near vertical. Roof pendants are common near some contacts and stoped blocks up to 700 m long are found within the Three Rivers stock. Contacts, pendants and stoped blocks generally display some combination of hornfelsing, brecciation, fracturing, faulting and mineralization. Sierra Blanca Volcanics display hydrothermal alteration increasing from argillic in the NW sector of the quad to high-temperature porpylitic near stock margins. Retrograde phyllic alteration occurs within breccia pipes and portions of the stocks. Mineral deposits consist of four types: Placer Au, fissure veins (mostly Ag-Pb-Zn±Au), breccia pipes (Au-Mo-Cu), and porphyry Mo-Cu. A singular pipe on the SW margin of Bonito Lake stock contains sapphire-lazulite-alunite. Although Au has been intermittently mined in the quad since 1865, best production of Au originated around the turn of the last

  20. Neurochemical Architecture of the Central Complex Related to Its Function in the Control of Grasshopper Acoustic Communication

    Science.gov (United States)

    Kunst, Michael; Pförtner, Ramona; Aschenbrenner, Katja; Heinrich, Ralf

    2011-01-01

    The central complex selects and coordinates the species- and situation-specific song production in acoustically communicating grasshoppers. Control of sound production is mediated by several neurotransmitters and modulators, their receptors and intracellular signaling pathways. It has previously been shown that muscarinic cholinergic excitation in the central complex promotes sound production whereas both GABA and nitric oxide/cyclic GMP signaling suppress its performance. The present immunocytochemical and pharmacological study investigates the question whether GABA and nitric oxide mediate inhibition of sound production independently. Muscarinic ACh receptors are expressed by columnar output neurons of the central complex that innervate the lower division of the central body and terminate in the lateral accessory lobes. GABAergic tangential neurons that innervate the lower division of the central body arborize in close proximity of columnar neurons and thus may directly inhibit these central complex output neurons. A subset of these GABAergic tangential neurons accumulates cyclic GMP following the release of nitric oxide from neurites in the upper division of the central body. While sound production stimulated by muscarine injection into the central complex is suppressed by co-application of sodium nitroprusside, picrotoxin-stimulated singing was not affected by co-application of this nitric oxide donor, indicating that nitric oxide mediated inhibition requires functional GABA signaling. Hence, grasshopper sound production is controlled by processing of information in the lower division of the central body which is subject to modulation by nitric oxide released from neurons in the upper division. PMID:21980504

  1. Small molecules CK-666 and CK-869 inhibit actin-related protein 2/3 complex by blocking an activating conformational change.

    Science.gov (United States)

    Hetrick, Byron; Han, Min Suk; Helgeson, Luke A; Nolen, Brad J

    2013-05-23

    Actin-related protein 2/3 (Arp2/3) complex is a seven-subunit assembly that nucleates branched actin filaments. Small molecule inhibitors CK-666 and CK-869 bind to Arp2/3 complex and inhibit nucleation, but their modes of action are unknown. Here, we use biochemical and structural methods to determine the mechanism of each inhibitor. Our data indicate that CK-666 stabilizes the inactive state of the complex, blocking movement of the Arp2 and Arp3 subunits into the activated filament-like (short pitch) conformation, while CK-869 binds to a serendipitous pocket on Arp3 and allosterically destabilizes the short pitch Arp3-Arp2 interface. These results provide key insights into the relationship between conformation and activity in Arp2/3 complex and will be critical for interpreting the influence of the inhibitors on actin filament networks in vivo. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Focus Article: Oscillatory and long-range monotonic exponential decays of electrostatic interactions in ionic liquids and other electrolytes: The significance of dielectric permittivity and renormalized charges

    Science.gov (United States)

    Kjellander, Roland

    2018-05-01

    A unified treatment of oscillatory and monotonic exponential decays of interactions in electrolytes is displayed, which highlights the role of dielectric response of the fluid in terms of renormalized (effective) dielectric permittivity and charges. An exact, but physically transparent statistical mechanical formalism is thereby used, which is presented in a systematic, pedagogical manner. Both the oscillatory and monotonic behaviors are given by an equation for the decay length of screened electrostatic interactions that is very similar to the classical expression for the Debye length. The renormalized dielectric permittivities, which have similar roles for electrolytes as the dielectric constant has for pure polar fluids, consist in general of several entities with different physical meanings. They are connected to dielectric response of the fluid on the same length scale as the decay length of the screened interactions. Only in cases where the decay length is very long, these permittivities correspond approximately to a dielectric response in the long-wavelength limit, like the dielectric constant for polar fluids. Experimentally observed long-range exponentially decaying surface forces are analyzed as well as the oscillatory forces observed for short to intermediate surface separations. Both occur in some ionic liquids and in concentrated as well as very dilute electrolyte solutions. The coexisting modes of decay are in general determined by the bulk properties of the fluid and not by the solvation of the surfaces; in the present cases, they are given by the behavior of the screened Coulomb interaction of the bulk fluid. The surface-fluid interactions influence the amplitudes and signs or phases of the different modes of the decay, but not their decay lengths and wavelengths. The similarities between some ionic liquids and very dilute electrolyte solutions as regards both the long-range monotonic and the oscillatory decays are analyzed.

  3. Thermodynamics, dielectric permittivity and phase diagrams of the Rb1-x(NH4xH2PO4 type proton glasses

    Directory of Open Access Journals (Sweden)

    S.I. Sorokov

    2010-01-01

    Full Text Available The cluster pseudospin model of proton glasses, which takes into account the energy levels of protons around the PO4 group, the long-range interactions between the hydrogen bonds, and an internal random deformational field is used to investigate thermodynamical characteristics, longitudinal and transverse dielectric permittivities of Rb1-x(ND4xD2PO4 and Rb1-x(NH4xH2AsO4 compounds. A review of experimental and theoretical works on the Rb1-x(NH4xH2PO4 type crystals is presented.

  4. A novel activating chicken IgY FcR is related to leukocyte receptor complex (LRC)

    NARCIS (Netherlands)

    Viertlboeck, B.C.; Schmitt, R.; Hanczaruk, M.A.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Gobel, T.W.

    2009-01-01

    FcRs have multifaceted roles in the immune system. Chicken FcRs were demonstrated on macrophages decades ago; however, only recently the chicken Ig-like receptor AB1, encoded in the leukocyte receptor complex, was molecularly identified as a high-affinity FcR. The present study was initiated to

  5. Structural basis for the recognition in an idiotype-anti-idiotype antibody complex related to celiac disease

    KAUST Repository

    Vangone, Anna

    2014-07-30

    Anti-idiotype antibodies have potential therapeutic applications in many fields, including autoimmune diseases. Herein we report the isolation and characterization of AIM2, an anti-idiotype antibody elicited in a mouse model upon expression of the celiac disease-specific autoantibody MB2.8 (directed against the main disease autoantigen type 2 transglutaminase, TG2). To characterize the interaction between the two antibodies, a 3D model of the MB2.8-AIM2 complex has been obtained by molecular docking. Analysis and selection of the different obtained docking solutions was based on the conservation within them of the inter-residue contacts. The selected model is very well representative of the different solutions found and its stability is confirmed by molecular dynamics simulations. Furthermore, the binding mode it adopts is very similar to that observed in most of the experimental structures available for idiotype-anti-idiotype antibody complexes. In the obtained model, AIM2 is directed against the MB2.8 CDR region, especially on its variable light chain. This makes the concurrent formation of the MB2.8-AIM2 complex and of the MB2.8-TG2 complex incompatible, thus explaining the experimentally observed inhibitory effect on the MB2.8 binding to TG2. © 2014 Vangone et al.

  6. Ligand-Centered Electron-Transfer Redox Processes for Manganese, Iron, and Cobalt Complexes in Relation to Selected Catalytic Systems

    Science.gov (United States)

    1989-05-01

    of Fe(acac)3 exhibits oxidation features common to acac- and its complexes. Table VIH (b) summarizes the EI/ 2 values for the oxidations of a number of...Data supplied by Dr. Pablo Cofr6 of the Universidad Cat6lica de Chile . 141. Chin, D.-H.; Chiericato, G., Jr.; Nanni, E. J., Jr.; Sawyer, D. T. 1. Am

  7. Basic skills in a complex task: A graphical model relating memory and lexical retrieval to simultaneous interpreting.

    NARCIS (Netherlands)

    Christoffels, I.K.; de Gtoor, A.M.B.; Waldorp, L.J.

    2003-01-01

    Simultaneous interpreting (SI) is a complex skill, where language comprehension and production take place at the same time in two different languages. In this study we identified some of the basic cognitive skills involved in SI, focusing on the roles of memory and lexical retrieval. We administered

  8. The development of second-order social cognition and its relation with complex language understanding and working memory

    NARCIS (Netherlands)

    Arslan, Burcu; Hohenberger, Annette; Verbrugge, Rineke

    2012-01-01

    In this study, the development of second-order social cognition and its possible relationship with language and memory were investigated. For this reason two second-order false belief tasks (FBT_2), a short term memory task (WST), a complex working memory task (LST), a linguistic perspective-taking

  9. Fixed Versus Variable Dosing of Prothrombin Complex Concentrate in Vitamin K Antagonist-Related Intracranial Hemorrhage : A Retrospective Analysis

    NARCIS (Netherlands)

    Abdoellakhan, Rahat Amadkhan; Miah, Ishita Parveen; Khorsand, Nakisa; Meijer, Karina; Jellema, Korne

    Millions of patients receive vitamin K antagonist (VKA) therapy worldwide. Annually 0.2-1 % of all VKA users develops an intracranial hemorrhage (ICH). Prothrombin complex concentrate (PCC) is administered to restore the INR In a before and after design, we compared successful achievement of an INR

  10. Catalytic ozonation not relying on hydroxyl radical oxidation: A selective and competitive reaction process related to metal-carboxylate complexes

    KAUST Repository

    Zhang, Tao

    2014-01-01

    Catalytic ozonation following non-hydroxyl radical pathway is an important technique not only to degrade refractory carboxylic-containing organic compounds/matter but also to avoid catalyst deactivation caused by metal-carboxylate complexation. It is unknown whether this process is effective for all carboxylates or selective to special molecule structures. In this work, the selectivity was confirmed using O3/(CuO/CeO2) and six distinct ozone-resistant probe carboxylates (i.e., acetate, citrate, malonate, oxalate, pyruvate and succinate). Among these probe compounds, pyruvate, oxalate, and citrate were readily degraded following the rate order of oxalate>citrate>pyruvate, while the degradation of acetate, malonate, and succinate was not promoted. The selectivity was independent on carboxylate group number of the probe compounds and solution pH. Competitive degradation was observed for carboxylate mixtures following the preference order of citrate, oxalate, and finally pyruvate. The competitive degradation was ascribed to competitive adsorption on the catalyst surface. It was revealed that the catalytically degradable compounds formed bidentate chelating or bridging complexes with surface copper sites of the catalyst, i.e., the active sites. The catalytically undegradable carboxylates formed monodentate complexes with surface copper sites or just electrostatically adsorbed on the catalyst surface. The selectivity, relying on the structure of surface metal-carboxylate complex, should be considered in the design of catalytic ozonation process. © 2013 Elsevier B.V.

  11. Structural basis for the recognition in an idiotype-anti-idiotype antibody complex related to celiac disease

    KAUST Repository

    Vangone, Anna; Abdel-Azeim, Safwat; Caputo, Ivana; Sblattero, Daniele; Di Niro, Roberto; Cavallo, Luigi; Oliva, Romina

    2014-01-01

    Anti-idiotype antibodies have potential therapeutic applications in many fields, including autoimmune diseases. Herein we report the isolation and characterization of AIM2, an anti-idiotype antibody elicited in a mouse model upon expression of the celiac disease-specific autoantibody MB2.8 (directed against the main disease autoantigen type 2 transglutaminase, TG2). To characterize the interaction between the two antibodies, a 3D model of the MB2.8-AIM2 complex has been obtained by molecular docking. Analysis and selection of the different obtained docking solutions was based on the conservation within them of the inter-residue contacts. The selected model is very well representative of the different solutions found and its stability is confirmed by molecular dynamics simulations. Furthermore, the binding mode it adopts is very similar to that observed in most of the experimental structures available for idiotype-anti-idiotype antibody complexes. In the obtained model, AIM2 is directed against the MB2.8 CDR region, especially on its variable light chain. This makes the concurrent formation of the MB2.8-AIM2 complex and of the MB2.8-TG2 complex incompatible, thus explaining the experimentally observed inhibitory effect on the MB2.8 binding to TG2. © 2014 Vangone et al.

  12. The challenge for genetic epidemiologists: how to analyze large numbers of SNPs in relation to complex diseases

    NARCIS (Netherlands)

    Heidema, A.G.; Boer, J.M.A.; Nagelkerke, N.; Mariman, E.C.M.; A, van der D.L.; Feskens, E.J.M.

    2006-01-01

    Genetic epidemiologists have taken the challenge to identify genetic polymorphisms involved in the development of diseases. Many have collected data on large numbers of genetic markers but are not familiar with available methods to assess their association with complex diseases. Statistical methods

  13. Exploring the complexities of leprosy-related stigma and the potential of a socio-economic intervention in a public health context in Indonesia

    NARCIS (Netherlands)

    Dadun,; Peters, Ruth; Lusli, Mimi; Miranda-Galarza, Beatriz; Van Brakel, Wim; Zweekhorst, Marjolein; Damayanti, Rita; Irwanto, A.; Bunders-Aelen, J.G.F.

    2016-01-01

    Purpose: This article explores the complexities of leprosy-related stigma and the potential effectiveness of a socio-economic intervention in Cirebon District, Indonesia. Methods: A qualitative approach was adopted. 53 people affected by leprosy were interviewed, and 17 focus group discussions were

  14. The Mycobacterium leprae antigen 85 complex gene family: identification of the genes for the 85A, 85C, and related MPT51 proteins

    NARCIS (Netherlands)

    Rinke de Wit, T. F.; Bekelie, S.; Osland, A.; Wieles, B.; Janson, A. A.; Thole, J. E.

    1993-01-01

    The genes for two novel members (designated 85A and 85C) of the Mycobacterium leprae antigen 85 complex family of proteins and the gene for the closely related M. leprae MPT51 protein were isolated. The complete DNA sequence of the M. leprae 85C gene and partial sequences of the 85A and MPT51 genes

  15. Effects of recombinant human granulocyte colony-stimulating factor on leucopenia in zidovudine-treated patients with AIDS and AIDS related complex, a phase I/II study

    NARCIS (Netherlands)

    van der Wouw, P. A.; van Leeuwen, R.; van Oers, R. H.; Lange, J. M.; Danner, S. A.

    1991-01-01

    Twelve male patients, eight with the acquired immunodeficiency syndrome (AIDS) and four with AIDS related complex (ARC), who had zidovudine associated neutropenia (less than 1 x 10(9) neutrophils/l) were treated with recombinant human granulocyte colony-stimulating factor (G-CSF) in a phase I/II

  16. Lyophilized kits of diamino dithiol compounds for labelling with 99m-technetium. Pharmacokinetics studies and distribution compartmental models of the related complexes

    International Nuclear Information System (INIS)

    Araujo, Elaine Bortoleti de

    1995-01-01

    The present work reflects the clinical interest for labelling diamino dithiol compounds with technetium-99m. Both chosen compounds, L,L-Ethylene dicysteine (L,L-EC) and L,L-Ethylene dicysteine diethyl esther (L,L-ECD) were obtained with relative good yield and characterized by IR and NMR. The study of labelling conditions with technetium-99m showed the influence of the type and mass of reducing agent as well as the pH on the formation of complexes with desired biological characteristics. Radiochemical purity was determined by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Lyophilised kits of L,L-EC and L,L-ECD for labelling with 99m Tc were obtained, with stability superior to 120 days, when stored under refrigeration, enabling the kits marketing. The ideal formulation of the kits as well as the use of liquid nitrogen in the freezing process, determined the lyophilization success. Distribution biological studies of the 99m Tc complexes were performed on mice by invasive method and on bigger animals by scintigraphic evaluation. Biological distribution studies of the complex 99m Tc-L,L-EC showed fast blood clearance, with the elimination of about 90% of the administered dose after 60 minutes, almost exclusively by the urinary system. The biological distribution results were adjusted to a three compartmental distribution model, as expected for a radiopharmaceutical designed to renal dynamic studies, with tubular elimination. The complex interaction with renal tubular receptors is related with structural characteristics of the compound, more specifically with the presence and location of polar groups. In comparison with 99m Tc-L,L-EC, biological studies of the complex 99m Tc -L,L-ECD showed different distribution aspects, despite some structural similarities. The presence of ethyl groups confers to the complex neutrality and lipophilicity. It cross the intact blood brain barrier and is retained in the brain for enough period

  17. Effect of task complexity on intelligence and neural efficiency in children: an event-related potential study.

    Science.gov (United States)

    Zhang, Qiong; Shi, Jiannong; Luo, Yuejia; Liu, Sainan; Yang, Jie; Shen, Mowei

    2007-10-08

    The present study investigates the effects of task complexity, intelligence and neural efficiency on children's performance on an Elementary Cognitive Task. Twenty-three children were divided into two groups on the basis of their Raven Progressive Matrix scores and were then asked to complete a choice reaction task with two test conditions. We recorded the electroencephalogram and calculated the peak latencies and amplitudes for anteriorly distributed P225, N380 and late positive component. Our results suggested shorter late positive component latencies in brighter children, possibly reflecting a higher processing speed in these individuals. Increased P225 amplitude and increased N380 amplitudes for brighter children may indicate a more efficient allocation of attention for brighter children. No moderating effect of task complexity on brain-intelligence relationship was found.

  18. Suicide and the 'Poison Complex': Toxic Relationalities, Child Development, and the Sri Lankan Self-Harm Epidemic.

    Science.gov (United States)

    Widger, Tom

    2015-01-01

    Suicide prevention efforts in Asia have increasingly turned to 'quick win' means restriction, while more complicated cognitive restriction and psychosocial programs are limited. This article argues the development of cognitive restriction programs requires greater consideration of suicide methods as social practices, and of how suicide cognitive schemata form. To illustrate this, the article contributes an ethnographically grounded study of how self-poisoning becomes cognitively available in Sri Lanka. I argue the overwhelming preference for poison as a method of self-harm in the country is not simply reflective of its widespread availability, but rather how cognitive schemata of poison-a 'poison complex'-develops from early childhood and is a precondition for suicide schemata. Limiting cognitive availability thus requires an entirely novel approach to suicide prevention that draws back from its immediate object (methods and causes of self-harm) to engage the wider poison complex of which suicide is just one aspect.

  19. Effect of complexing reagents on the ionization constant of boric acid and its relation to isotopic exchange separation factor

    International Nuclear Information System (INIS)

    Sharma, B.K.; Subramanian, R.; Mathur, P.K.

    1991-01-01

    The effect of change in concentration of complexing reagents having two or more hydroxyl groups, viz., ethylene glycol, propylene glycol, dextrose and mannitol on the ionization constant of boric acid has been studied by pH-metric titration method. The effect of increase in ionization constant of boric acid on isotopic exchange separation factor for the separation of isotopes of boron by ion exchange chromatography has been studied by the batch method. (author). 9 refs

  20. Inferring selection in the Anopheles gambiae species complex: an example from immune-related serine protease inhibitors

    Directory of Open Access Journals (Sweden)

    Little Tom J

    2009-06-01

    Full Text Available Abstract Background Mosquitoes of the Anopheles gambiae species complex are the primary vectors of human malaria in sub-Saharan Africa. Many host genes have been shown to affect Plasmodium development in the mosquito, and so are expected to engage in an evolutionary arms race with the pathogen. However, there is little conclusive evidence that any of these mosquito genes evolve rapidly, or show other signatures of adaptive evolution. Methods Three serine protease inhibitors have previously been identified as candidate immune system genes mediating mosquito-Plasmodium interaction, and serine protease inhibitors have been identified as hot-spots of adaptive evolution in other taxa. Population-genetic tests for selection, including a recent multi-gene extension of the McDonald-Kreitman test, were applied to 16 serine protease inhibitors and 16 other genes sampled from the An. gambiae species complex in both East and West Africa. Results Serine protease inhibitors were found to show a marginally significant trend towards higher levels of amino acid diversity than other genes, and display extensive genetic structuring associated with the 2La chromosomal inversion. However, although serpins are candidate targets for strong parasite-mediated selection, no evidence was found for rapid adaptive evolution in these genes. Conclusion It is well known that phylogenetic and population history in the An. gambiae complex can present special problems for the application of standard population-genetic tests for selection, and this may explain the failure of this study to detect selection acting on serine protease inhibitors. The pitfalls of uncritically applying these tests in this species complex are highlighted, and the future prospects for detecting selection acting on the An. gambiae genome are discussed.

  1. Positron annihilation studies of bio-related N2S2-tetradentate ligands and their zinc complexes

    International Nuclear Information System (INIS)

    Shaban, S.Y.; Mahmoud, K.R.; Sharshar, T.

    2013-01-01

    In this study, a series of three N 2 S 2 -tetradentate ligands and their zinc complexes were investigated by positron annihilation lifetime spectroscopy. The measurements were performed at room temperature. The analysis of lifetime spectra of all samples yielded four lifetime components, except in one sample that yielded three components. The results showed that the formation probability and lifetime of ortho-positronium in this series are dependent on the structure.

  2. Are Pain-Related Fears Mediators for Reducing Disability and Pain in Patients with Complex Regional Pain Syndrome Type 1? An Explorative Analysis on Pain Exposure Physical Therapy

    Science.gov (United States)

    Barnhoorn, Karlijn J.; Staal, J. Bart; van Dongen, Robert T. M.; Frölke, Jan Paul M.; Klomp, Frank P.; van de Meent, Henk; Samwel, Han; Nijhuis-van der Sanden, Maria W. G.

    2015-01-01

    Objective To investigate whether pain-related fears are mediators for reducing disability and pain in patients with Complex Regional Pain Syndrome type 1 when treating with Pain Exposure Physical Therapy. Design An explorative secondary analysis of a randomised controlled trial. Participants Fifty-six patients with Complex Regional Pain Syndrome type 1. Interventions The experimental group received Pain Exposure Physical Therapy in a maximum of five treatment sessions; the control group received conventional treatment following the Dutch multidisciplinary guideline. Outcome measures Levels of disability, pain, and pain-related fears (fear-avoidance beliefs, pain catastrophizing, and kinesiophobia) were measured at baseline and after 3, 6, and 9 months follow-up. Results The experimental group had a significantly larger decrease in disability of 7.77 points (95% CI 1.09 to 14.45) and in pain of 1.83 points (95% CI 0.44 to 3.23) over nine months than the control group. The potential mediators pain-related fears decreased significantly in both groups, but there were no significant differences between groups, which indicated that there was no mediation. Conclusion The reduction of pain-related fears was comparable in both groups. We found no indication that pain-related fears mediate the larger reduction of disability and pain in patients with Complex Regional Pain Syndrome type 1 treated with Pain Exposure Physical Therapy compared to conventional treatment. Trial registration International Clinical Trials Registry NCT00817128 PMID:25919011

  3. Photoluminescence related to Gd3+:N-vacancy complex in GaN:Gd multi-quantum wells

    International Nuclear Information System (INIS)

    Almokhtar, Mohamed; Emura, Shuichi; Koide, Akihiro; Fujikawa, Takashi; Asahi, Hajime

    2015-01-01

    Highlights: • We grew Gd-doped GaN multi-quantum wells (MQWs) with quantum layer thickness of one nm by MBE. • The X-ray absorption near edge structure spectra observed at Gd LIII-edge indicate a nitrogen vacancy adjacent to Gd substituting the Ga ion in Gd-doped GaN MQW. • The photoluminescence of the samples is discussed considering the formation of a Gd 3+ :Nitrogen-vacancy complex. • A model is presented considering exciton-polaron formation trapped in defect sites around the Gd 3+ :N-vacancy complex in Gd-doped GaN MQWs. - Abstract: The photoluminescence of Gd-doped GaN multi-quantum wells (MQWs) is presented and discussed considering the formation of a Gd 3+ :Nitrogen-vacancy (N-vacancy) complex. A lower energy photoluminescence peak was observed for the Gd-doped GaN MQW sample with respect to the main peak assigned to a neutral donor bound exciton (D 0 X) of the undoped GaN MQW sample. The X-ray absorption near edge structure spectrum observed at Gd L III -edge indicates a nitrogen vacancy adjacent to the Gd substituting the Ga ion in Gd-doped GaN MQW sample. Local stresses around the Gd dopants in Gd-doped GaN matrix generated due to the larger diameter of the Gd 3+ ion with respect to the Ga 3+ ion can be relieved by the creation of vacancies. The lower formation energy of N-vacancies in GaN matrix introduce them as a preferred candidate to relieve the generated stresses. A Gd 3+ :N-vacancy complex consisting of a Gd 3+ ion and the created nitrogen vacancy adjacent to the Gd 3+ dopant is likely to form in GaN:Gd matrix. The lower photoluminescence peak energy observed in the Gd-doped GaN MQW sample is assigned to the recombination of an exciton captured at the Gd 3+ :N-vacancy complex forming a small polaron-like state. A model is presented considering the small exciton-polaron population in defect sites captured around the Gd 3+ ions in the Gd-doped GaN

  4. Reliably measuring the condition of mineral-based transfer fluids using a permittivity sensor – practical application to thermal fluid heat transfer

    Directory of Open Access Journals (Sweden)

    Christopher Ian Wright

    2015-09-01

    Full Text Available This article describes a series of experiments to assess the performance and suitability of a permittivity sensor in the area of heat transfer. The permittivity sensor measures condition index and temperature of a fluid. A series of 5 experiments was conducted. They assessed the reproducibility of the sensor using both clean and dirty fluid samples, and showed the sensor had good reproducibility based on calculations of coefficients of variation. The sensor also detected water contamination, assessed from construction of a stimulus-response curve to step-wise increases in water and from real-life samples where water content was reported to be out of specification. Further experiments tested the association between condition index and both water content and fluid cleanliness in a real-life setting. Results demonstrated the sensor that condition index reflected changes in fluid water and cleanliness and was therefore a measure of fluid condition. The implication of these findings is that the sensor can be used to make rapid and reliable assessments of fluid condition using only small samples (i.e., <50 ml. The sensor may be of benefit to customers that need to make a lot of regular samples over a large processing site, such as concentrated solar power plants.

  5. Unique negative permittivity of the pseudo conducting radial zinc oxide-poly(vinylidene fluoride) nanocomposite film: Enhanced dielectric and electromagnetic interference shielding properties

    Energy Technology Data Exchange (ETDEWEB)

    Aepuru, Radhamanohar [Department of Materials Engineering, Defence Institute of Advanced Technology, Girinagar, Pune 411025 (India); Bhaskara Rao, B.V.; Kale, S.N. [Department of Applied Physics, Defence Institute of Advanced Technology, Pune 411025 (India); Panda, H.S., E-mail: himanshusp@diat.ac.in [Department of Materials Engineering, Defence Institute of Advanced Technology, Girinagar, Pune 411025 (India)

    2015-11-01

    Flower like radial zinc oxide (RZnO) was prepared by using a facile solvothermal method and used to prepare poly(vinylidene fluoride) (PVDF) based nanocomposites. Structural informations of the samples are analyzed by X-ray diffraction and correlated with high resolution transmission electron microscopy along with high annular angular dark field scanning transmission electron microscopy (HAADF-STEM). For the first time, stability studies are carried out by solvent relaxation nuclear magnetic resonance experiments. Dielectric studies of the PVDF and PVDF-RZnO nanocomposites are reported over the wide range of frequency (0.01 Hz–1 MHz) and temperature (25–90 °C). Dielectric property of the PVDF-RZnO nanocomposites was significantly improved wrt filler percentage in PVDF. Unique negative permittivity was observed in the composites having higher filler content (>40 wt%) typically at low frequencies. First time, it is observed that the higher RZnO content in PVDF results the formation of pseudo conducting network and hence improved the electromagnetic shielding efficiency (85%) than PVDF and PVDF-commercial ZnO composites. - Highlights: • Radial ZnO-PVDF nanocomposites were fabricated by using solution casting. • Pseudo conducting network is confirmed through cryo-fracture morphology study. • Stability study of the nano fillers was performed in the polymer matrix. • Unique negative permittivity behavior of the nanocomposites was observed. • EMI shielding property of the radial ZnO-PVDF nanocomposites was performed.

  6. Multi-mode technique for the determination of the biaxial Y{sub 2}SiO{sub 5} permittivity tensor from 300 to 6 K

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, N. C., E-mail: natalia.docarmocarvalho@research.uwa.edu.au; Le Floch, J-M.; Tobar, M. E. [School of Physics, The University of Western Australia, Crawley 6009 (Australia); ARC Centre of Excellence for Engineered Quantum Systems (EQuS), 35 Stirling Hwy, Crawley 6009 (Australia); Krupka, J. [Instytut Mikroelektroniki i Optoelektroniki PW, Koszykowa 75, 00-662 Warsaw (Poland)

    2015-05-11

    The Y{sub 2}SiO{sub 5} (YSO) crystal is a dielectric material with biaxial anisotropy with known values of refractive index at optical frequencies. It is a well-known rare-earth (RE) host material for optical research and more recently has shown promising performance for quantum-engineered devices. In this paper, we report the first microwave characterization of the real permittivity tensor of a bulk YSO sample, as well as an investigation of the temperature dependence of the tensor components from 296 K down to 6 K. Estimated uncertainties were below 0.26%, limited by the precision of machining the cylindrical dielectric. Also, the electrical Q-factors of a few electromagnetic modes were recorded as a way to provide some information about the crystal losses over the temperature range. To solve the tensor components necessary for a biaxial crystal, we developed the multi-mode technique, which uses simultaneous measurement of low order whispering gallery modes. Knowledge of the permittivity tensor offers important data, essential for the design of technologies involving YSO, such as microwave coupling to electron and hyperfine transitions in RE doped samples at low temperatures.

  7. Predominant Expression of Hybrid N-Glycans Has Distinct Cellular Roles Relative to Complex and Oligomannose N-Glycans

    Directory of Open Access Journals (Sweden)

    M. Kristen Hall

    2016-06-01

    Full Text Available Glycosylation modulates growth, maintenance, and stress signaling processes. Consequently, altered N-glycosylation is associated with reduced fitness and disease. Therefore, expanding our understanding of N-glycans in altering biological processes is of utmost interest. Herein, clustered regularly interspaced short palindromic repeats/caspase9 (CRISPR/Cas9 technology was employed to engineer a glycosylation mutant Chinese Hamster Ovary (CHO cell line, K16, which expresses predominantly hybrid type N-glycans. This newly engineered cell line enabled us to compare N-glycan effects on cellular properties of hybrid type N-glycans, to the well-established Pro−5 and Lec1 cell lines, which express complex and oligomannose types of N-glycans, respectively. Lectin binding studies revealed the predominant N-glycan expressed in K16 is hybrid type. Cell dissociation and migration assays demonstrated the greatest strength of cell–cell adhesion and fastest migratory rates for oligomannose N-glycans, and these properties decreased as oligomannose type were converted to hybrid type, and further decreased upon conversion to complex type. Next, we examined the roles of three general types of N-glycans on ectopic expression of E-cadherin, a cell–cell adhesion protein. Microscopy revealed more functional E-cadherin at the cell–cell border when N-glycans were oligomannose and these levels decreased as the oligomannose N-glycans were processed to hybrid and then to complex. Thus, we provide evidence that all three general types of N-glycans impact plasma membrane architecture and cellular properties.

  8. Influence of complex circumstances and risks related to human relibaility: case of integral circuits fabrication in sterile environment

    International Nuclear Information System (INIS)

    Doniol-Shaw, G.

    1991-08-01

    Concepts of operating the complex and risk bearing utilities tend to separate operators from potential sources of risk (automation, and remote control). Since isolation of operators from risk sources is not always possible and constant their exposure to risks during operation, the question of human errors is always an important issue. In such situations, independent of the control and failure detection systems, operators are responsible for achieving two objectives simultaneously: operation and safety. This presentation shows how human behaviour can be determined by safety conditions of a plant, in the frame of managing minor real risks that would cause minor

  9. Spectroelectrochemistry: A valuable tool for the study of organometallic-alkyne, -vinylidene, -cumulene, -alkynyl and related complexes

    International Nuclear Information System (INIS)

    Low, Paul J.; Bock, Sören

    2013-01-01

    This review presents a highly selective summary of spectroelectrochemical methods used in the study of metal alkyne, acetylide, vinylidene and allenylidene complexes. The review is illustrated predominantly by the selected examples from the authors’ group that formed the basis of a lecture at the recent ISE Annual Meeting. Emphasis is placed on the use of spectroelectrochemical methods to study redox-induced ligand isomerisation reactions, and determination of molecular electronic structure, which complement the conventional tools available to the synthetic chemist for characterisation of molecular compounds. The role of computational studies in supporting the interpretation of spectroscopic data is also briefly discussed

  10. Total adiponectin and adiponectin multimeric complexes in relation to weight loss-induced improvements in insulin sensitivity in obese women

    DEFF Research Database (Denmark)

    Polak, J.; Kovacova, Z.; Holst, C.

    2008-01-01

    , and LMW). The HMW form was suggested to be closely associated with insulin sensitivity. This study investigated whether diet-induced changes in insulin sensitivity were associated with changes in adiponectin multimeric complexes. SUBJECTS: Twenty obese women with highest and twenty obese women with lowest...... diet induced changes in insulin sensitivity (responders and non-responders respectively), matched for weight loss (body mass index (BMI)=34.5 (s.d. 2.9) resp. 36.5 kg/m(2) (s.d. 4.0) for responders and non-responders), were selected from 292 women who underwent a 10-week low-caloric diet (LCD; 600 kcal...

  11. Structure-function relations in oxaloacetate decarboxylase complex. Fluorescence and infrared approaches to monitor oxomalonate and Na(+ binding effect.

    Directory of Open Access Journals (Sweden)

    Thierry Granjon

    Full Text Available BACKGROUND: Oxaloacetate decarboxylase (OAD is a member of the Na(+ transport decarboxylase enzyme family found exclusively in anaerobic bacteria. OAD of Vibrio cholerae catalyses a key step in citrate fermentation, converting the chemical energy of the decarboxylation reaction into an electrochemical gradient of Na(+ ions across the membrane, which drives endergonic membrane reactions such as ATP synthesis, transport and motility. OAD is a membrane-bound enzyme composed of alpha, beta and gamma subunits. The alpha subunit contains the carboxyltransferase catalytic site. METHODOLOGY/PRINCIPAL FINDINGS: In this report, spectroscopic techniques were used to probe oxomalonate (a competitive inhibitor of OAD with respect to oxaloacetate and Na(+ effects on the enzyme tryptophan environment and on the secondary structure of the OAD complex, as well as the importance of each subunit in the catalytic mechanism. An intrinsic fluorescence approach, Red Edge Excitation Shift (REES, indicated that solvent molecule mobility in the vicinity of OAD tryptophans was more restricted in the presence of oxomalonate. It also demonstrated that, although the structure of OAD is sensitive to the presence of NaCl, oxomalonate was able to bind to the enzyme even in the absence of Na(+. REES changes due to oxomalonate binding were also observed with the alphagamma and alpha subunits. Infrared spectra showed that OAD, alphagamma and alpha subunits have a main component band centered between 1655 and 1650 cm(-1 characteristic of a high content of alpha helix structures. Addition of oxomalonate induced a shift of the amide-I band of OAD toward higher wavenumbers, interpreted as a slight decrease of beta sheet structures and a concomitant increase of alpha helix structures. Oxomalonate binding to alphagamma and alpha subunits also provoked secondary structure variations, but these effects were negligible compared to OAD complex. CONCLUSION: Oxomalonate binding affects the

  12. Emotion Regulation in Context: The Jealousy Complex between Young Siblings and Its Relations with Child and Family Characteristics.

    Science.gov (United States)

    Volling, Brenda L.; McElwain, Nancy L.; Miller, Alison L.

    2002-01-01

    Examined relations between sibling jealousy and child and family characteristics in families with toddler and preschool-age siblings. Found that positive marital relationship was particularly strong predictor of older siblings' abilities to regulate jealousy in sessions with mothers. Younger siblings' jealous affect with mothers related to child's…

  13. Coffin-Siris syndrome and related disorders involving components of the BAF (mSWI/SNF) complex: historical review and recent advances using next generation sequencing.

    Science.gov (United States)

    Kosho, Tomoki; Miyake, Noriko; Carey, John C

    2014-09-01

    This issue of Seminars in Medical Genetics, American Journal of Medical Genetics Part C investigates the human diseases caused by mutations in the BAF complex (also known as the mammalian SWI/SNF complex) genes, particularly focusing on Coffin-Siris syndrome (CSS). CSS is a rare congenital malformation syndrome characterized by developmental delay or intellectual disability (ID), coarse facial appearance, feeding difficulties, frequent infections, and hypoplasia/aplasia of the fifth fingernails and fifth distal phalanges. In 2012, 42 years after the first description of CSS in 1970, five causative genes (SMARCB1, SMARCE1, SMARCA4, ARID1A, ARID1B), all encoding components of the BAF complex, were identified as being responsible for CSS through whole exome sequencing and pathway-based genetic screening. The identification of two additional causative genes (PHF6, SOX11) followed. Mutations in another BAF complex gene (SMARCA2) and (TBC1D24) were found to cause clinically similar conditions with ID, Nicolaides-Baraitser syndrome and DOORS syndrome, respectively. Also, ADNP was found to be mutated in an autism/ID syndrome. Furthermore, there is growing evidences for germline or somatic mutations in the BAF complex genes to be causal for cancer/cancer predisposition syndromes. These discoveries have highlighted the role of the BAF complex in the human development and cancer formation. The biology of BAF is very complicated and much remains unknown. Ongoing research is required to reveal the whole picture of the BAF complex in human development, and will lead to the development of new targeted therapies for related disorders in the future. © 2014 Wiley Periodicals, Inc.

  14. Effect of a magnetic field on the permittivity of 80%La0.7Sr0.3MnO3/20%GeO2 composite

    Science.gov (United States)

    Kabirov, Yu. V.; Gavrilyachenko, V. G.; Bogatin, A. S.; Sitalo, E. I.; Yatsenko, V. K.

    2018-01-01

    The dielectric properties of a magnetoresistive conducting two-phase 80%La0.7Sr0.3MnO3/20%GeO2 (wt %) composite have been studied near the percolation threshold in magnetic fields from 0 to 15 kOe at frequencies of the measurement field from 5 kHz to 1 MHz. The samples have inductive impedances; i.e., their permittivities can be considered negative due to a high conductivity in this frequency range. The permittivity increases in magnitude in magnetic field, and the values of the magnetodielectric coefficient reach 23% at room temperature. The reasons for the effect of magnetic field on the dielectric permittivity of samples are discussed.

  15. Propagation and Interaction Properties of Successive Coronal Mass Ejections in Relation to a Complex Type II Radio Burst

    Science.gov (United States)

    Liu, Y. D.; Zhao, X.; Zhu, B.

    2017-12-01

    We examine the propagation and interaction properties of three successive coronal mass ejections (CMEs) from 2001 November 21-22, with a focus on their connection with the behaviors of the associated long-duration complex type II radio burst. In combination with coronagraph and multi-point in situ observations, the long-duration type II burst provides key features that help resolve the propagation and interaction complexities of the three CMEs. The two CMEs from November 22 interacted first and then overtook the November 21 CME at a distance of about 0.85 AU from the Sun. The time scale that the shock originally driven by the last CME spent inside the preceding two CMEs is estimated to be about 14 and 6 hr, respectively. We present a simple analytical model without any free parameters to characterize the whole Sun-to-Earth propagation of the shock, which shows a remarkable consistency with all the available data and MHD simulations even out to the distance of Ulysses (2.34 AU). The coordination of in situ measurements at the Earth and Ulysses, which were separated by 73o in latitude, gives important clues for the understanding of shock structure and the interpretation of in situ signatures. The results also indicate means to increase geo-effectiveness with three CMEs, similar to the the ``perfect storm" scenario proposed by te{liu14a} although the current case is not ``super" in the same sense as the 2012 July 23 event.

  16. WASH and WAVE actin regulators of the Wiskott-Aldrich syndrome protein (WASP) family are controlled by analogous structurally related complexes.

    Science.gov (United States)

    Jia, Da; Gomez, Timothy S; Metlagel, Zoltan; Umetani, Junko; Otwinowski, Zbyszek; Rosen, Michael K; Billadeau, Daniel D

    2010-06-08

    We recently showed that the Wiskott-Aldrich syndrome protein (WASP) family member, WASH, localizes to endosomal subdomains and regulates endocytic vesicle scission in an Arp2/3-dependent manner. Mechanisms regulating WASH activity are unknown. Here we show that WASH functions in cells within a 500 kDa core complex containing Strumpellin, FAM21, KIAA1033 (SWIP), and CCDC53. Although recombinant WASH is constitutively active toward the Arp2/3 complex, the reconstituted core assembly is inhibited, suggesting that it functions in cells to regulate actin dynamics through WASH. FAM21 interacts directly with CAPZ and inhibits its actin-capping activity. Four of the five core components show distant (approximately 15% amino acid sequence identify) but significant structural homology to components of a complex that negatively regulates the WASP family member, WAVE. Moreover, biochemical and electron microscopic analyses show that the WASH and WAVE complexes are structurally similar. Thus, these two distantly related WASP family members are controlled by analogous structurally related mechanisms. Strumpellin is mutated in the human disease hereditary spastic paraplegia, and its link to WASH suggests that misregulation of actin dynamics on endosomes may play a role in this disorder.

  17. Phobias of attachment-related inner states in the psychotherapy of adult survivors of childhood complex trauma.

    Science.gov (United States)

    Liotti, Giovanni

    2013-11-01

    The clinical case described in this article illustrates the value of taking into account the dynamics of disorganized attachment in the assessment of attachment-related phobias (phobia of attachment and phobia of attachment loss) during the psychotherapy of chronically traumatized patients. These seemingly opposite phobias typically coexist in the same patient, appear as phobias of both inner states (affect phobias) and relational experiences, and are linked to dissociated representations of self-with-other. Theory and research on attachment disorganization provide a clinician-friendly conceptual framework for capturing both the intrapsychic (e.g., intrusive and nonintegrated mental states) and the relational (e.g., dramatic unsolvable dilemmas in interpersonal exchanges) aspects of the attachment-related phobias. The therapeutic strategy and the key interventions that logically follow from a case formulation based on this conceptual framework are examined. © 2013 Wiley Periodicals, Inc.

  18. Some geodynamic complexities related to the evolution of Bengal Fan and the neotectonic activity of the south Indian shield

    Digital Repository Service at National Institute of Oceanography (India)

    Murthy, K.S.R.

    crust, trends of fracture zones, origin and age of the hotspot traces in relation to the break up and drift of the Indian Plate. Recent inferences on the deformation from Peninsular shield have introduced further complications on the tectonics...

  19. The antimalarial activity of Ru-chloroquine complexes against resistant Plasmodium falciparum is related to lipophilicity, basicity, and heme aggregation inhibition ability near water/n-octanol interfaces.

    Science.gov (United States)

    Martínez, Alberto; Rajapakse, Chandima S K; Jalloh, Dalanda; Dautriche, Cula; Sánchez-Delgado, Roberto A

    2009-08-01

    We have measured water/n-octanol partition coefficients, pK(a) values, heme binding constants, and heme aggregation inhibition activity of a series of ruthenium-pi-arene-chloroquine (CQ) complexes recently reported to be active against CQ-resistant strains of Plasmodium falciparum. Measurements of heme aggregation inhibition activity of the metal complexes near water/n-octanol interfaces qualitatively predict their superior antiplasmodial action against resistant parasites, in relation to CQ; we conclude that this modified method may be a better predictor of antimalarial potency than standard tests in aqueous acidic buffer. Some interesting tendencies emerge from our data, indicating that the antiplasmodial activity is related to a balance of effects associated with the lipophilicity, basicity, and structural details of the compounds studied.

  20. The antimalarial activity of Ru–chloroquine complexes against resistant Plasmodium falciparum is related to lipophilicity, basicity, and heme aggregation inhibition ability near water/n-octanol interfaces

    Science.gov (United States)

    Martínez, Alberto; Rajapakse, Chandima S. K.; Jalloh, Dalanda; Dautriche, Cula

    2012-01-01

    We have measured water/n-octanol partition coefficients, pKa values, heme binding constants, and heme aggregation inhibition activity of a series of ruthenium–πarene–chloroquine (CQ) complexes recently reported to be active against CQ-resistant strains of Plasmodium falciparum. Measurements of heme aggregation inhibition activity of the metal complexes near water/n-octanol interfaces qualitatively predict their superior antiplasmodial action against resistant parasites, in relation to CQ; we conclude that this modified method may be a better predictor of antimalarial potency than standard tests in aqueous acidic buffer. Some interesting tendencies emerge from our data, indicating that the antiplasmodial activity is related to a balance of effects associated with the lipophilicity, basicity, and structural details of the compounds studied. PMID:19343380