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Sample records for hybrid lh slow

  1. Hybrid Composites for LH2 Fuel Tank Structure

    Science.gov (United States)

    Grimsley, Brian W.; Cano, Roberto J.; Johnston, Norman J.; Loos, Alfred C.; McMahon, William M.

    2001-01-01

    The application of lightweight carbon fiber reinforced plastics (CFRP) as structure for cryogenic fuel tanks is critical to the success of the next generation of Reusable Launch Vehicles (RLV). The recent failure of the X-33 composite fuel tank occurred in part due to microcracking of the polymer matrix, which allowed cryogen to permeate through the inner skin to the honeycomb core. As part of an approach to solve these problems, NASA Langley Research Center (LaRC) and Marshall Space Flight Center (MSFC) are working to develop and investigate polymer films that will act as a barrier to the permeation of LH2 through the composite laminate. In this study two commercially available films and eleven novel LaRC films were tested in an existing cryogenics laboratory at MSFC to determine the permeance of argon at room temperature. Several of these films were introduced as a layer in the composite to form an interleaved, or hybrid, composite to determine the effects on permeability. In addition, the effects of the interleaved layer thickness, number, and location on the mechanical properties of the composite laminate were investigated. In this initial screening process, several of the films were found to exhibit lower permeability to argon than the composite panels tested.

  2. The causal impact of magnetic fluctuations in slow and fast L-H transitions at TJ-II

    CERN Document Server

    van Milligen, B Ph; Carreras, B A; Ascasíbar, E; Hidalgo, C; Pastor, I; Fontdecaba, J M; Balbín, R

    2015-01-01

    This work focuses on the relationship between L-H transitions and MHD activity in the low shear TJ-II stellarator. It is shown that the presence of a low order rational in the plasma edge (gradient) region lowers the threshold density for H-mode access. MHD activity is systematically suppressed before or at the confinement transition. We apply a causality detection technique (the Transfer Entropy) to study the relation between magnetic oscillations and locally measured plasma rotation velocity (related to Zonal Flows). For this purpose, we study a large number of discharges in two magnetic configurations, corresponding to fast and slow transitions. With the slow transitions, the developing Zonal Flow prior to the transition leads to the gradual reduction of magnetic oscillations. The transition itself is marked by a strong spike of 'information transfer' from magnetic to velocity oscillations, suggesting the that the magnetic drive is important for setting up the final sheared flow responsible for the H-mode ...

  3. A broad slow frequencies band and high slowing down factor by using one-dimensional hybrid periodic/Fibonacci photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ben Ali, N; Kanzari, M, E-mail: naimgi2@yahoo.fr [Photovoltaic and Semiconductor Materials Laboratory, El-Manar University-ENIT PO Box 37, Le belvedere 1002-Tunis (Tunisia)

    2010-11-15

    By using a theoretical model based on Transfer Matrix Method (TMM) for normal incidence simulator, and for serial (S) polarisation, the slowing of light in one-dimensional (1D) hybrid (Fibonacci{sub 1}/periodic/Fibonacci{sub 2}) photonic crystals is studied at visible frequency band. Effects of the periodicity, the non-periodicity and the number of layers of each photonic structure on the slowing down of light are discussed. The higher slowing down factors was obtained by the hybrid Fibonacci{sub 1}/periodic/Fibonacci{sub 2} structures. This slowing down factors is greater than those corresponding to the periodic, the Fibonacci, the Thue-Morse and the Cantor band-gap structures. In addition this hybrid structure gives the possibility to slowing several frequencies

  4. Slow electron energy balance for hybrid models of direct-current glow discharges

    Science.gov (United States)

    Eliseev, S. I.; Bogdanov, E. A.; Kudryavtsev, A. A.

    2017-09-01

    In this paper, we present the formulation of slow electron energy balance for hybrid models of direct current (DC) glow discharge. Electrons originating from non-local ionization (secondary) contribute significantly to the energy balance of slow electrons. An approach towards calculating effective energy brought by a secondary electron to the group of slow electrons by means of Coulomb collisions is suggested. The value of effective energy shows a considerable dependence on external parameters of a discharge, such as gas pressure, type, and geometric parameters. The slow electron energy balance was implemented into a simple hybrid model that uses analytical formulation for the description of non-local ionization by fast electrons. Simulations of short (without positive column) DC glow discharge in argon are carried out for a range of gas pressures. Comparison with experimental data showed generally good agreement in terms of current-voltage characteristics, electron density, and electron temperature. Simulations also capture the trend of increasing electron density with decreasing pressure observed in the experiment. Analysis shows that for considered conditions, the product of maximum electron density ne and electron temperature Te in negative glow is independent of gas pressure and depends on the gas type, cathode material, and discharge current. Decreasing gas pressure reduces the heating rate of slow electrons during Coulomb collisions with secondary electrons, which leads to lower values of Te and, in turn, higher maximum ne.

  5. Hybrid single-beam reconstruction technique for slow and fast varying wave fields.

    Science.gov (United States)

    Falaggis, Konstantinos; Kozacki, Tomasz; Kujawinska, Malgorzata

    2015-06-01

    An iterative single-beam wave field reconstruction technique that employs both non-paraxial, wave propagation based and paraxial deterministic phase retrieval techniques is presented. This approach overcomes two major obstacles that exist in the current state of the art techniques: iterative methods do not reconstruct slowly varying wave fields due to slow convergence and stagnation, and deterministic methods have paraxial limits, making the reconstructions of quickly varying object features impossible. In this work, a hybrid approach is reported that uses paraxial wave field corrections within iterative phase retrieval solvers. This technique is suitable for cases ranging from slow to fast varying wave fields, and unlike the currently available methods, can also reconstruct measurement objects with different regions of both slowly and quickly varying object features. It is further shown that this technique gives a higher accuracy than current single-beam phase retrieval techniques, and in comparison to the iterative methods, has a higher convergence speed.

  6. Hybrid stochastic simulation of reaction-diffusion systems with slow and fast dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Strehl, Robert; Ilie, Silvana, E-mail: silvana@ryerson.ca [Department of Mathematics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada)

    2015-12-21

    In this paper, we present a novel hybrid method to simulate discrete stochastic reaction-diffusion models arising in biochemical signaling pathways. We study moderately stiff systems, for which we can partition each reaction or diffusion channel into either a slow or fast subset, based on its propensity. Numerical approaches missing this distinction are often limited with respect to computational run time or approximation quality. We design an approximate scheme that remedies these pitfalls by using a new blending strategy of the well-established inhomogeneous stochastic simulation algorithm and the tau-leaping simulation method. The advantages of our hybrid simulation algorithm are demonstrated on three benchmarking systems, with special focus on approximation accuracy and efficiency.

  7. Multiple electromagnetically induced transparency, slow and fast light in hybrid optomechanics

    CERN Document Server

    Akram, M Javed; Saif, Farhan

    2015-01-01

    We theoretically investigate the phenomenon of electromagnetically induced transparency (EIT) of a weak probe field in hybrid optomechanics with a single three-level ($\\Lambda$-type) atomic system. We report that, in the presence of optomechanical coupling and two transition coupling parameters of three-level atom (TLA), there occurs three distinct multiple EIT windows in the probe absorption spectrum. Moreover, the switching of multiple windows into double and single EIT windows can be obtained by suitably tuning the system parameters. Furthermore, the probe transmission spectrum have been studied. Based on our analytical and numerical work, we explain the occurrence of slow and fast light (superluminal) regimes, and enhancement of superluminal behaviour in the probe field transmission. This work demonstrates great potential in multi-channel waveguide, fiber optics and classical communication networks, multi-channel quantum information processing, real quality imaging, cloaking devices and delay lines & ...

  8. Research Update: Relativistic origin of slow electron-hole recombination in hybrid halide perovskite solar cells

    Science.gov (United States)

    Azarhoosh, Pooya; McKechnie, Scott; Frost, Jarvist M.; Walsh, Aron; van Schilfgaarde, Mark

    2016-09-01

    The hybrid perovskite CH3NH3PbI3 (MAPI) exhibits long minority-carrier lifetimes and diffusion lengths. We show that slow recombination originates from a spin-split indirect-gap. Large internal electric fields act on spin-orbit-coupled band extrema, shifting band-edges to inequivalent wavevectors, making the fundamental gap indirect. From a description of photoluminescence within the quasiparticle self-consistent GW approximation for MAPI, CdTe, and GaAs, we predict carrier lifetime as a function of light intensity and temperature. At operating conditions we find radiative recombination in MAPI is reduced by a factor of more than 350 compared to direct gap behavior. The indirect gap is retained with dynamic disorder.

  9. Hybrid metal-dielectric, slow wave structure with magnetic coupling and compensation

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A.V., E-mail: asmirnov@radiabeam.com [RadiaBeam Systems LLC, 1713 Stewart St., Santa Monica, CA 90404 (United States); Savin, E. [RadiaBeam Systems LLC, 1713 Stewart St., Santa Monica, CA 90404 (United States); National Research Nuclear University “MEPhI”, Moscow 115409 (Russian Federation)

    2016-06-01

    A number of electron beam vacuum devices such as small radiofrequency (RF) linear accelerators (linacs) and microwave traveling wave tubes (TWTs) utilize slow wave structures which are usually rather complicated in production and may require multi-step brazing and time consuming tuning. Fabrication of these devices becomes challenging at centimeter wavelengths, at large number of cells, and when a series or mass production of such structures is required. A hybrid, metal-dielectric, periodic structure for low gradient, low beam current applications is introduced here as a modification of Andreev’s disk-and-washer (DaW) structure. Compensated type of coupling between even and odd TE01 modes in the novel structure results in negative group velocity with absolute values as high as 0.1c–0.2c demonstrated in simulations. Sensitivity to material imperfections and electrodynamic parameters of the disk-and-ring (DaR) structure are considered numerically using a single cell model.

  10. Research Update: Relativistic origin of slow electron-hole recombination in hybrid halide perovskite solar cells

    Directory of Open Access Journals (Sweden)

    Pooya Azarhoosh

    2016-09-01

    Full Text Available The hybrid perovskite CH3NH3PbI3 (MAPI exhibits long minority-carrier lifetimes and diffusion lengths. We show that slow recombination originates from a spin-split indirect-gap. Large internal electric fields act on spin-orbit-coupled band extrema, shifting band-edges to inequivalent wavevectors, making the fundamental gap indirect. From a description of photoluminescence within the quasiparticle self-consistent GW approximation for MAPI, CdTe, and GaAs, we predict carrier lifetime as a function of light intensity and temperature. At operating conditions we find radiative recombination in MAPI is reduced by a factor of more than 350 compared to direct gap behavior. The indirect gap is retained with dynamic disorder.

  11. Effects of different irrigation methods and plant densities on silage quality parameters of PR 31Y43 hybrid corn cultivar (Zea mays L. var. indentata [Sturtev.] L.H. Bailey

    Directory of Open Access Journals (Sweden)

    Muhammet Karasahin

    2014-03-01

    Full Text Available The yield and quality of corn silage is related to genotype as well as factors such as climate, soil conditions, altitude, planting time, plant density, irrigation, and harvesting time. This study was conducted to determine the effects of different irrigation methods (drip, subsoil drip, and subsoil capillary and different plant densities (102 040, 119 040, and 142 850 plant ha-1 on silage quality parameters of PR 31Y43 hybrid corn (Zea mays L. var. indentata [Sturtev.] L.H. Bailey in 2011 and 2012 under ecological conditions in Eskipazar-Karabuk, Turkey. Plant densities were significantly different on fresh ear ratio and plant crude protein (CP yield in both years under study. The highest fresh ear ratio values were obtained with 102 040 and 119 040 plant ha-1 densities and the highest plant CP yield with 142 850 plant ha-1. While the irrigation method x plant density interactions were significant for silage CP ratio in the first year, they were significant on fresh ear ratio in the second year. The highest fresh ear ratio values were obtained from subsoil capillary x 119 040 plant ha-1 and drip x 119 040 plant ha-1 interactions; the highest plant and silage CP ratio values were obtained from subsoil capillary x 142 850 plant ha-1 and subsoil drip x 102 040 plant ha-1 interactions. As a result of the research, high Flieg scores were obtained from each irrigation method and plant density. When plant CP yield is taken into consideration, the 142 850 plant ha-1 density is more important.

  12. Overview of LH experiments in JET with an ITER-like wall

    Energy Technology Data Exchange (ETDEWEB)

    Kirov, K. K.; Baranov, Yu.; Brix, M.; Corrigan, G.; Mailloux, J.; Rimini, F.; Stamp, M. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Barbato, E. [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, Roma (Italy); Ekedahl, A.; Goniche, M. [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France); Petrzilka, V. [Association EURATOM-IPP.CR, IPP AS CR, 182 21 Praha 8 (Czech Republic); Collaboration: JET EFDA Contributors

    2014-02-12

    An overview of the recent results of Lower Hybrid (LH) experiments at JET with the ITER-like wall (ILW) is presented. Topics relevant to LH wave coupling are addressed as well as issues related to ILW and LH system protections. LH wave coupling was studied in conditions determined by ILW recycling and operational constraints. It was concluded that LH wave coupling was not significantly affected and the pre-ILW performance could be recovered after optimising the launcher position and local gas puffing. SOL density measurements were performed using a Li-beam diagnostic. Dependencies on the D2 injection rate from the dedicated gas valve, the LH power and the LH launcher position were analysed. SOL density modifications due to LH were modelled by the EDGE2D code assuming SOL heating by collisional dissipation of the LH wave and/or possible ExB drifts in the SOL. The simulations matched reasonably well the measured SOL profiles. Observations of arcs and hotspots with visible and IR cameras viewing the LH launcher are presented.

  13. Identification of waves in the lower-hybrid frequency range in the scrape-off layer plasma of Alcator C-Mod

    Science.gov (United States)

    Shinya, Takahiro; Gyou Baek, Seung; Wallace, Gregory M.; Shiraiwa, Syun'ichi; Takase, Yuichi; Parker, Ronald R.; Bonoli, Paul T.; Brunner, Dan; Faust, Ian; LaBombard, Brian L.; Wukitch, Steve

    2017-03-01

    Polarization resolved measurements of the parallel refractive index {{N}\\parallel}\\equiv c{{k}\\parallel}/ω of the driven RF waves in the lower hybrid (LH) range of frequencies are performed using arrays of RF magnetic probes in the scrape-off layer plasma of Alcator C-Mod. The measured {{N}\\parallel} of the RF magnetic field component parallel to the background magnetic field is about  -1.6, which corresponds to the peak of the launched LH {{N}\\parallel} spectrum. Based on the wave dispersion relationship, this wave is identified as the LH slow wave. On the other hand, the RF magnetic field component perpendicular to the magnetic field is found to have a lower {{N}\\parallel} of  -1.2, and is detected only near the last closed flux surface. This wave is identified as the LH fast wave generated by slow-fast wave mode conversion.

  14. Operation and coupling of LH waves with the ITER-like wall at JET

    CERN Document Server

    Kirov, K K; Ekedahl, A; Petrzilka, V; Arnoux, G; Baranov, Yu; Brix, M; Goniche, M; Jachmich, S; Mayoral, M-L; Ongena, J; Rimini, F; Stamp, M; Contributors, JET EFDA

    2013-01-01

    In this paper important aspects of Lower Hybrid (LH) operation with the ITER Like Wall (ILW) [1] at JET are reported. Impurity release during LH operation was investigated and it was found that there is no significant Be increase with LH power. Concentration of W was analysed in more detail and it was concluded that LH contributes negligibly to its increase. No cases of W accumulation in LH-only heating experiments were observed so far. LH wave coupling was studied and optimised to achieve the level of system performance similar to before ILW installation. Measurements by Li-beam were used to study systematic dependencies of the SOL density on the gas injection rate from a dedicated gas introduction module and the LH power and launcher position. Experimental results are supported by SOL transport modelling. Observations of arcs in front of the LH launcher and hotspots on magnetically connected sections of the vessel are reported. Overall, a relatively troublefree operation of the LH system up to 2.5MW of coup...

  15. Extreme Supernova Models for the Superluminous Transient ASASSN-15lh

    CERN Document Server

    Chatzopoulos, E; Vinko, J; Nagy, A P; Wiggins, B K; Even, W P

    2016-01-01

    The recent discovery of the unprecedentedly superluminous transient ASASSN-15lh (or SN 2015L) challenges all the power-input models that have been proposed for superluminous supernovae. Here we examine some of the few viable interpretations of ASASSN-15lh in the context of a stellar explosion, involving combinations of one or more power inputs. We model the lightcurve of ASASSN-15lh with a hybrid model that includes contributions from magnetar spin-down energy and hydrogen-poor circumstellar interaction. We also investigate models of pure circumstellar interaction with a massive hydrogen-deficient shell and discuss about the lack of interaction features in the observed spectra. We find that ASASSN-15lh can be best modeled by the energetic core-collapse of a ~40 Msun supernova interacting with a hydrogen-poor shell of ~20 Msun. The circumstellar shell and progenitor mass are consistent with a rapidly rotating pulsational pair-instability supernova progenitor as required for strong interaction following the fin...

  16. Spontaneous and induced loss of chromosomes in slow-growing somatic hybrid calli of Solanum tuberosum and Nicotiana plumbaginifolia

    NARCIS (Netherlands)

    Tempelaar, MJ; Drenth - Diephuis, L.J.; SAAT, TAWM; Jacobsen, E.

    1991-01-01

    Rate and extent of spontaneous and induced chromosome loss have been determined at the callus level of somatic hybrids of mutants of Solanum tuberosum and Nicotiana plumbaginifolia. AEC (amino ethyl cystein) resistance in potato and Nitrate-Reductase deficiency in N. plumbaginifolia have been used a

  17. Bifurcation analysis and dimension reduction of a predator-prey model for the L-H transition

    DEFF Research Database (Denmark)

    Dam, Magnus; Brøns, Morten; Juul Rasmussen, Jens

    2013-01-01

    The L-H transition denotes a shift to an improved confinement state of a toroidal plasma in a fusion reactor. A model of the L-H transition is required to simulate the time dependence of tokamak discharges that include the L-H transition. A 3-ODE predator-prey type model of the L-H transition...... is investigated with bifurcation theory of dynamical systems. The analysis shows that the model contains three types of transitions: an oscillating transition, a sharp transition with hysteresis, and a smooth transition. The model is recognized as a slow-fast system. A reduced 2-ODE model consisting of the full...... model restricted to the flow on the critical manifold is found to contain all the same dynamics as the full model. This means that all the dynamics in the system is essentially 2-dimensional, and a minimal model of the L-H transition could be a 2-ODE model....

  18. Bifurcation analysis and dimension reduction of a predator-prey model for the L-H transition

    Science.gov (United States)

    Dam, Magnus; Brøns, Morten; Juul Rasmussen, Jens; Naulin, Volker; Xu, Guosheng

    2013-10-01

    The L-H transition denotes a shift to an improved confinement state of a toroidal plasma in a fusion reactor. A model of the L-H transition is required to simulate the time dependence of tokamak discharges that include the L-H transition. A 3-ODE predator-prey type model of the L-H transition is investigated with bifurcation theory of dynamical systems. The analysis shows that the model contains three types of transitions: an oscillating transition, a sharp transition with hysteresis, and a smooth transition. The model is recognized as a slow-fast system. A reduced 2-ODE model consisting of the full model restricted to the flow on the critical manifold is found to contain all the same dynamics as the full model. This means that all the dynamics in the system is essentially 2-dimensional, and a minimal model of the L-H transition could be a 2-ODE model.

  19. Bifurcation analysis and dimension reduction of a predator-prey model for the L-H transition

    Energy Technology Data Exchange (ETDEWEB)

    Dam, Magnus; Brøns, Morten [Department of Applied Mathematics and Computer Science, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Juul Rasmussen, Jens; Naulin, Volker [Association Euratom-DTU, Department of Physics, Technical University of Denmark, DTU Risø Campus, DK-4000 Roskilde (Denmark); Xu, Guosheng [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2013-10-15

    The L-H transition denotes a shift to an improved confinement state of a toroidal plasma in a fusion reactor. A model of the L-H transition is required to simulate the time dependence of tokamak discharges that include the L-H transition. A 3-ODE predator-prey type model of the L-H transition is investigated with bifurcation theory of dynamical systems. The analysis shows that the model contains three types of transitions: an oscillating transition, a sharp transition with hysteresis, and a smooth transition. The model is recognized as a slow-fast system. A reduced 2-ODE model consisting of the full model restricted to the flow on the critical manifold is found to contain all the same dynamics as the full model. This means that all the dynamics in the system is essentially 2-dimensional, and a minimal model of the L-H transition could be a 2-ODE model.

  20. LH Dynamics in Overweight Girls with Premature Adrenarche and Slowly Progressive Sexual Precocity

    Directory of Open Access Journals (Sweden)

    Rosenfield RobertL

    2010-08-01

    Full Text Available Background. Excess adiposity and premature adrenarche (PA are risk factors for the development of polycystic ovary syndrome (PCOS. Methods. Girls with slowly progressive precocious breast development, who were overweight and had PA (SPPOPA, 6.2–8.2 years, , overweight PA (6.6–10.8 years, , and overweight premenarcheal controls (OW-PUB, 10.6–12.8 years, underwent hormonal sleep testing and GnRH agonist (GnRHag and ACTH tests. Results. Despite an insignificant sleep-related increase in LH and prepubertal baseline hormone levels, SPPOPA peak LH and estradiol responses to GnRHag were intermediate between those of PA and OW-PUB, the LH being significantly different from both. Conclusions. GnRHag tests indicate that SPPOPA is a slowly progressive form of true puberty with blunted LH dynamics. These results argue against the prepubertal hyperandrogenism of excess adiposity or PA enhancing LH secretion or causing ovarian hyperandrogenism prior to menarche. Excess adiposity may contribute to both the early onset and slow progression of puberty.

  1. Perovskite photovoltaics: Slow recombination unveiled

    Science.gov (United States)

    Moser, Jacques-E.

    2017-01-01

    One of the most salient features of hybrid lead halide perovskites is the extended lifetime of their photogenerated charge carriers. This property has now been shown experimentally to originate from a slow, thermally activated recombination process.

  2. Study of EAST LH antennas coupling at ENEA-Frascati

    Energy Technology Data Exchange (ETDEWEB)

    Panaccione, L.; Mirizzi, F. [Consorzio CREATE, Via Claudio 21, 80125, Napoli (Italy); Ceccuzzi, S.; Cesario, R.; Tuccillo, A. A., E-mail: angelo.tuccillo@enea.it [ENEA for EUROfusion, via E. Fermi 45, 00044 Frascati (RM) (Italy); Ding, B. J.; Li, M.; Liu, F.; Liu, L.; Shan, J. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-12-10

    The two Lower Hybrid (LH) launchers of the EAST tokamak have been analysed using some tools available at ENEA-Frascati research centre. The antennas, working at 2.45 and 4.6 GHz, have been assessed in terms of reflection coefficient and launched power spectrum for several plasma loads differing in the electron density profile. Fitting an experimental profile we derived a set of parameterised realistic density profiles to compute the coupling performances of different spectra, launched by considering different phasing between antenna modules. The sensitivity to the tilt of the magnetic field with respect to the equatorial plane as well as to an additional progressive phasing at the mouth due to the toroidal curvature has been studied too. The most suitable operational conditions for the minimization of reflected power and side lobes in the n{sub ||} spectra are identified.

  3. Influence of bovine LH tracer quality on levels of LH in GnRH-treated cows

    Energy Technology Data Exchange (ETDEWEB)

    Madej, A.; Hallin, P.; Madej, M.; Seguin, B.; Edqvist, L.E.

    1989-01-01

    Chromatography of 125I-bovine LH (LER-1716-2 and USDA-I-1) by means of anion exchange high performance liquid chromatography (HPLC) revealed two main peaks of radioactivity regardless as to whether or not the tracer was initially purified on cellulose CF11. The content of radioactivity in the first peak tended to increase as the storage time of the bLH preparation, either before or after iodination, increased. The first peak of radioactivity after HPLC fractionation either with or without cellulose adsorption consisted of material with low binding ability to bLH antiserum (6.9% +/- 0.5 and 13.0% +/- 1.0, respectively) and high binding ability to ovine LH alpha antiserum (51.0% +/- 2.7 and 35.2% +/- 3.6, respectively). The average ratio of alpha-subunit immuno-reactivity to 125I-bLH immunoreactivity in this material was 7.4 +/- 0.1 and 2.7 +/- 0.2, respectively (P less than 0.001). Peaks in 125I-bLH radioactivity and 125I-bLH immunoreactivity had different elution times. Radioimmunoassays with tracers obtained from fractions derived from the first radioactive peak after HPLC chromatography (i.e. 125I-bLH-LER-1716-2) both with and without cellulose adsorption, yielded significantly lower mean plasma LH levels in GnRH-treated cows compared with the control tracer routinely purified only on cellulose CF11 (e.g. 5.7 vs. 8.2 micrograms/; 4.6 vs. 8.2 micrograms/l). Plasma LH levels in GnRH-treated cows were significantly (P less than 0.001) lower as measured by radioimmunoassay utilizing 125I-USDA-blH-I-1 tracers than by radioimmunoassays utilizing 125I-blH-LER-1716-2 tracers (i.e. either Y = 0.17 + 0.75X or Y = 1.18 + 0.60X).

  4. Understanding the role of LH: myths and facts.

    Science.gov (United States)

    Fischer, Robert

    2007-10-01

    This review summarizes a series of lectures given at a recent Continuing Medical Education meeting in Hamburg, Germany (May 2007), aiming to understand the role of luteinizing hormone (LH) in follicular development during the natural menstrual cycle and controlled ovarian stimulation. Clinical situations and target groups of patients who might benefit from LH supplementation during their ovarian stimulation were discussed and defined. The lectures updated knowledge on the physiology of LH during the normal menstrual cycle and the role of LH in ovarian stimulation. The concept of the 'LH window' was presented, and the use of LH supplementation in different groups of patients undergoing controlled ovarian stimulation was discussed, including those with advanced age, hypogonadotrophic hypogonadism, pituitary down-regulation and poor response. In addition, the different ways of using LH or human chorionic gonadotrophin supplementation in ovulation induction protocols were described.

  5. Slow Heartbeat

    Science.gov (United States)

    ... per minute. The heartbeat is controlled by an electrical system that signals the heart muscle to contract, or “squeeze,” pumping blood to the rest of the body. Bradycardia happens when the system slows or blocks ...

  6. Investigation of lower hybrid physics through power modulation experiments on Alcator C-Moda)

    Science.gov (United States)

    Schmidt, A.; Bonoli, P. T.; Meneghini, O.; Parker, R. R.; Porkolab, M.; Shiraiwa, S.; Wallace, G.; Wright, J. C.; Harvey, R. W.; Wilson, J. R.

    2011-05-01

    Lower hybrid current drive (LHCD) is an attractive tool for off-axis current profile control in magnetically confined tokamak plasmas and burning plasmas (ITER), because of its high current drive efficiency. The LHCD system on Alcator C-Mod operates at 4.6 GHz, with ~ 1 MW of coupled power, and can produce a wide range of launched parallel refractive index (n||) spectra. A 32 chord, perpendicularly viewing hard x-ray camera has been used to measure the spatial and energy distribution of fast electrons generated by lower hybrid (LH) waves. Square-wave modulation of LH power on a time scale much faster than the current relaxation time does not significantly alter the poloidal magnetic field inside the plasma and thus allows for realistic modeling and consistent plasma conditions for different n|| spectra. Inverted hard x-ray profiles show clear changes in LH-driven fast electron location with differing n||. Boxcar binning of hard x-rays during LH power modulation allows for ~ 1 ms time resolution which is sufficient to resolve the build-up, steady-state, and slowing-down phases of fast electrons. Ray-tracing/Fokker-Planck modeling in combination with a synthetic hard x-ray diagnostic shows quantitative agreement with the x-ray data for high n|| cases. The time histories of hollow x-ray profiles have been used to measure off-axis fast electron transport in the outer half of the plasma, which is found to be small on a slowing down time scale.

  7. Heat loads on JET plasma facing components from ICRF and LH wave absorption in the SOL

    Science.gov (United States)

    Jacquet, P.; Colas, L.; Mayoral, M.-L.; Arnoux, G.; Bobkov, V.; Brix, M.; Coad, P.; Czarnecka, A.; Dodt, D.; Durodie, F.; Ekedahl, A.; Frigione, D.; Fursdon, M.; Gauthier, E.; Goniche, M.; Graham, M.; Joffrin, E.; Korotkov, A.; Lerche, E.; Mailloux, J.; Monakhov, I.; Noble, C.; Ongena, J.; Petrzilka, V.; Portafaix, C.; Rimini, F.; Sirinelli, A.; Riccardo, V.; Vizvary, Z.; Widdowson, A.; Zastrow, K.-D.; EFDA Contributors, JET

    2011-10-01

    In JET, lower hybrid (LH) and ion cyclotron resonance frequency (ICRF) wave absorption in the scrape-off layer can lead to enhanced heat fluxes on some plasma facing components (PFCs). Experiments have been carried out to characterize these heat loads in order to: (i) prepare JET operation with the Be wall which has a reduced power handling capability as compared with the carbon wall and (ii) better understand the physics driving these wave absorption phenomena and propose solutions for next generation systems to reduce them. When using ICRF, hot spots are observed on the antenna structures and on limiters close to the powered antennas and are explained by acceleration of ions in RF-rectified sheath potentials. High temperatures up to 800 °C can be reached on locations where a deposit has built up on tile surfaces. Modelling which takes into account the fast thermal response of surface layers can reproduce well the surface temperature measurements via infrared (IR) imaging, and allow evaluation of the heat fluxes local to active ICRF antennas. The flux scales linearly with the density at the antenna radius and with the antenna voltage. Strap phasing corresponding to wave spectra with lower kpar values can lead to a significant increase in hot spot intensity in agreement with antenna modelling that predicts, in that case, an increase in RF sheath rectification. LH absorption in front of the antenna through electron Landau damping of the wave with high Npar components generates hot spots precisely located on PFCs magnetically connected to the launcher. Analysis of the LH hot spot surface temperature from IR measurements allows a quantification of the power flux along the field lines: in the worst case scenario it is in the range 15-30 MW m-2. The main driving parameter is the LH power density along the horizontal rows of the launcher, the heat fluxes scaling roughly with the square of the LH power density. The local electron density in front of the grill increases

  8. 'Carriers of variant luteinizing hormone (V-LH) among 1593 Baltic men have significantly higher serum LH'.

    Science.gov (United States)

    Punab, A M; Grigorova, M; Punab, M; Adler, M; Kuura, T; Poolamets, O; Vihljajev, V; Žilaitienė, B; Erenpreiss, J; Matulevičius, V; Laan, M

    2015-05-01

    Luteinizing hormone (LH) is a pituitary heterodimeric glycoprotein essential in male and female reproduction. Its functional polymorphic variant (V-LH) is determined by two missense mutations (rs1800447, A/G, Trp8Arg; rs34349826, A/G, Ile15Thr) in the LH β-subunit encoding gene (LHB; 19q13.3; 1111 bp; 3 exons). Among women, V-LH has been associated with higher circulating LH and reduced fertility, but the knowledge of its effect on male reproductive parameters has been inconclusive. The objective of this study was to assess the effect of V-LH on hormonal, seminal and testicular parameters in the Baltic young men cohort (n = 986; age: 20.1 ± 2.1 years) and Estonian idiopathic infertility patients (n = 607; 35.1 ± 5.9 years). V-LH was detected by genotyping of the underlying DNA polymorphisms using PCR-RFLP combined with resequencing of a random subset of subjects. Genetic associations were tested using linear regression under additive model and results were combined in meta-analysis. No significant difference was detected between young men and infertility patients for the V-LH allele frequency (11.0 vs. 9.3%, respectively). V-LH was associated with higher serum LH in both, the young men cohort (p = 0.022, allelic effect = 0.26 IU/L) and the idiopathic infertility group (p = 0.008, effect = 0.59 IU/L). In meta-analysis, the statistical significance was enhanced (p = 0.0007, resistant to Bonferroni correction for multiple testing; effect = 0.33 IU/L). The detected significant association of V-LH with increased serum LH remained unchanged after additional adjustment for the SNPs previously demonstrated to affect LH levels (FSHB -211G/T, FSHR Asn680Ser, FSHR -29A/G). Additionally, a suggestive trend for association with reduced testicular volume was observed among young men, and with lower serum FSH among infertility patients. The V-LH carrier status did not affect sperm parameters and other circulating reproductive hormones. For the first time, we show a conclusive

  9. Dopamine control of LH release in the tench (Tinca tinca).

    Science.gov (United States)

    Podhorec, Peter; Socha, Magdalena; Sokolowska-Mikolajczyk, Miroslawa; Policar, Tomas; Svinger, Viktor W; Drozd, Borek; Kouril, Jan

    2012-01-01

    Tench (Tinca tinca) is apparently the only known member of the Cyprinidae in which ovulation is stimulated following administration of a low dose of GnRH analogue (GnRHa) without a dopamine inhibitor. This study evaluated LH release effectiveness of the most commonly used GnRHa and clarified whether LH secretion followed by ovulation is subject to inhibitory dopaminergic control in tench. Fish were intraperitoneally injected with three types of GnRHa, GnRHa with dopamine inhibitor metoclopramide (combined treatment), or the dopamine inhibitor metoclopramide alone. LH concentrations at five sampling times (0, 6, 12, 24, and 33 h) together with ovulation success and fecundity index were recorded. The combined treatment triggered an almost immediate LH release peak with a gradual decline, and resulted in a high ovulation rate. In contrast to the combined treatment, an application of GnRHa alone at 10 μg kg(-1) induced gradual increase of LH concentrations with peaks close to ovulation time, and with high ovulation success. Significant differences in LH concentrations at 6 and 12h and no differences in ovulation success were found between the combined and the GnRHa alone treatments. Metoclopramide alone induced a small increase in LH with no ovulation. The study presents clear evidence of dopaminergic control of LH release in tench, with a high ovulation rate obtained after application of GnRHa alone or in combination with dopamine inhibitor.

  10. Luteinizing hormone (LH) and prolactin-releasing pituitary tumor: possible malignant transformation of the LH cell line.

    Science.gov (United States)

    Spertini, F; Deruaz, J P; Perentes, E; Pelet, B; Gomez, F

    1986-05-01

    A pituitary tumor was diagnosed in a prepubertal 13-yr-old girl, who had elevated plasma LH (58 mIU/ml) and PRL (93 ng/ml) levels; decreased GH, ACTH, and FSH secretion; and diabetes insipidus. After surgery, plasma LH and PRL declined, but not to normal levels. Conventional external radiotherapy to the pituitary was immediately followed by a decrease in LH to prepubertal values (0.7 mIU/ml), while PRL levels became normal only after a long course of bromocriptine therapy. The pituitary tumor was composed of two distinct cell types: small polygonal cells, which were PRL positive by immunohistochemistry, and clusters of pleomorphic large frequently mitotic polynucleated cells, which were LH positive, some of them also being positive for the alpha-subunit or beta LH but not for beta FSH. Four years after surgery and radiotherapy, the patient deteriorated neurologically. Computed tomographic scan showed widespread frontal and periventricular tumor, which had the histological features of a poorly differentiated carcinoma. No PRL, LH, or alpha- or beta-subunits were detectable on immunocytochemistry. While the PRL-positive cells of the pituitary tumor displayed the histological and clinical features of PRL adenomas, the morphological characteristics of LH cells and the sharp decline of plasma LH levels after radiotherapy were suggestive of malignant transformation. In this context, the later brain tumor could have been the result of subependymal spread of the pituitary tumor after it lost its hormone-secreting capacity.

  11. L-H power threshold studies in JET with Be/W and C wall

    Science.gov (United States)

    Maggi, C. F.; Delabie, E.; Biewer, T. M.; Groth, M.; Hawkes, N. C.; Lehnen, M.; de la Luna, E.; McCormick, K.; Reux, C.; Rimini, F.; Solano, E. R.; Andrew, Y.; Bourdelle, C.; Bobkov, V.; Brix, M.; Calabro, G.; Czarnecka, A.; Flanagan, J.; Lerche, E.; Marsen, S.; Nunes, I.; Van Eester, D.; Stamp, M. F.; EFDA Contributors, JET

    2014-02-01

    A comparison of the L-H power threshold (Pthr) in JET with all carbon, JET-C, and beryllium/tungsten wall (the ITER-like choice), JET-ILW, has been carried out in experiments with slow input power ramps and matched plasma shapes, divertor configuration and IP/BT pairs. The low density dependence of the L-H power threshold, namely an increase below a minimum density ne,min, which was first observed in JET with the MkII-GB divertor and C wall and subsequently not observed with the current MkII-HD geometry, is observed again with JET-ILW. At plasma densities above ne,min, Pthr is reduced by ˜30%, and by ˜40% when the radiation from the bulk plasma is subtracted (Psep), with JET-ILW compared to JET-C. At the L-H transition the electron temperature at the edge, where the pedestal later develops, is also lower with JET-ILW, for a given edge density. With JET-ILW the minimum density is found to increase roughly linearly with magnetic field, n_{e,min} \\sim B_{T}^{4/5} , while the power threshold at the minimum density scales as P_{sep,\\min} \\sim B_{T}^{5/2} . The H-mode power threshold in JET-ILW is found to be sensitive both to variations in main plasma shape (Psep decreases with increasing lower triangularity and increases with upper triangularity) and in divertor configuration. When the data are recast in terms of Psep and Zeff or subdivertor neutral pressure a linear correlation is found, pointing to a possible role of Zeff and/or subdivertor neutral pressure in the L-H transition physics. Depending on the chosen divertor configuration, Pthr can be up to a factor of two lower than the ITPA scaling law for densities above ne,min. A shallow edge radial electric field well is observed at the L-H transition. The edge impurity ion poloidal velocity remains low, close to its L-mode values, ⩽5 km s-1 ± 2-3 km s-1, at the L-H transition and throughout the H-mode phase, with no measureable increase within the experimental uncertainties. The edge toroidal rotation

  12. Effects of Progestin and Antiprogestin on the Expression of FSH Receptor and LH Receptor mRNA in Porcine Granulosa and Thecal Cells

    Institute of Scientific and Technical Information of China (English)

    吴尔若; 刘德瑜; 赵金来; 吴燕婉

    2000-01-01

    In order to investigate the mechanism of progestin and antiprogestin in the regula-tion of ovarian steroidogenesis, a dual-chamber culture system was prepared with the amnion membrane of human placenta. Isolated porcine granulosa and thecal cells from 4~6 mm-diameter follicles were grown on both sides of the amnion, respectively, and co-cultured with or without LNG and RU486. After 48 h incubation, the mRNAs of FSH receptor (FSH-R) and LH receptor (LH-R) of both cells were observed by in situ hybridization. The results showed that granulosa cells expressed both FSH-R mR-NA and LH-R mRNA, while thecal cells expressed LH-R mRNA only. Under the stimulation of FSH, both LNG and RU486 increased FSH-R mRNA expression of granulosa cells. Under the stimulation of LH, LNG enhanced LH-R mRNA expres-sion of thecal cells;while RU486 decreased its expression. When granulosa and thecal cells were exposed to FSH and LH both, the actions of LNG and RU 486 in thecal cells showed the same result as that stimulated by LH alone. In granulosa cells LNG de-creased LH-R mRNA expression, while RU486 increased its expression. These data suggest that; (1) granulosa cells expressed FSH-R mRNA significantly; (2) both the progestin and antiprogestin directly acted on the mRNA expression of gonadotropin re-ceptors of ovarian cells, but effects were different; (3) the response of granulosa or thecal cells to the action of LNG and RU486 was not the same. The mechanism needs to be further investigated.

  13. Extreme Supernova Models for the Super-luminous Transient ASASSN-15lh

    Science.gov (United States)

    Chatzopoulos, E.; Wheeler, J. C.; Vinko, J.; Nagy, A. P.; Wiggins, B. K.; Even, W. P.

    2016-09-01

    The recent discovery of the unprecedentedly super-luminous transient ASASSN-15lh (or SN 2015L) with its UV-bright secondary peak challenges all the power-input models that have been proposed for super-luminous supernovae. Here we examine some of the few viable interpretations of ASASSN-15lh in the context of a stellar explosion, involving combinations of one or more power inputs. We model the light curve of ASASSN-15lh with a hybrid model that includes contributions from magnetar spin-down energy and hydrogen-poor circumstellar interaction. We also investigate models of pure circumstellar interaction with a massive hydrogen-deficient shell and discuss the lack of interaction features in the observed spectra. We find that, as a supernova, ASASSN-15lh can be best modeled by the energetic core-collapse of an ˜40 M ⊙ star interacting with a hydrogen-poor shell of ˜20 M ⊙. The circumstellar shell and progenitor mass are consistent with a rapidly rotating pulsational pair-instability supernova progenitor as required for strong interaction following the final supernova explosion. Additional energy injection by a magnetar with an initial period of 1-2 ms and magnetic field of 0.1-1 × 1014 G may supply the excess luminosity required to overcome the deficit in single-component models, but this requires more fine-tuning and extreme parameters for the magnetar, as well as the assumption of efficient conversion of magnetar energy into radiation. We thus favor a single-input model where the reverse shock formed in a strong SN ejecta-circumstellar matter interaction following a very powerful core-collapse SN explosion can supply the luminosity needed to reproduce the late-time UV-bright plateau.

  14. Edge radial electric field formation after the L-H transition on JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Kamiya, K.; Matsunaga, G.; Honda, M.; Miyato, N.; Urano, H.; Kamada, Y.; Itoh, K. [Japan Atomic Energy Agency (JAEA), Naka (Japan); Ida, K. [National Institute for Fusion Science (NIFS), Toki (Japan); Collaboration: The JT-60 team

    2014-06-15

    Spatio-temporal measurements of the impurity ion temperature, density, and rotation profiles around the plasma edge region have been made in the JT-60U tokamak, allowing the determination of radial electric field, E{sub r}, with the key dimensionless parameter (poloidal Mach number, U{sub pm)} at the L-H transition in a number of operational regimes. We found that there is variation in the L-H transition in terms of its time-scale; not only ''hard'' type transition with a faster time-scale than that seen in the plasma transport (as represented by an energy confinement time, τ{sub E}) as seen in the many conventional tokamaks, but also ''soft'' one with a slow time-scale (∼τ{sub E}) is possible solution, including a complex multi-stage E{sub r} transition in the later H-phase. The most important point is that the critical condition for the L-H transition predicted by ion-orbit loss model could be applicable only for ''hard'' transition (occurred at U{sub pm} ≥ 1), and not necessary for ''slow'' one (occurred even at U{sub pm} < 1). Characteristics of the turbulent density fluctuation with the frequency range of 100 kHz at the plasma edge region, in addition to a uniform toroidal MHD oscillation (i.e., n = 0), during ELM-free H-phase are also reported. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Reproductive Strategy and Sexual Conflict Slow Life History Strategy Inihibts Negative Androcentrism

    Directory of Open Access Journals (Sweden)

    Paul R. Gladden

    2013-11-01

    Full Text Available Recent findings indicate that a slow Life History (LH strategy factor is associated with increased levels of Executive Functioning (EF, increased emotional intelligence, decreased levels of sexually coercive behaviors, and decreased levels of negative ethnocentrism. Based on these findings, as well as the generative theory, we predicted that slow LH strategy should inhibit negative androcentrism (bias against women. A sample of undergraduates responded to a battery of questionnaires measuring various facets of their LH Strategy, (e.g., sociosexual orientation, mating effort, mate-value, psychopathy, executive functioning, and emotional intelligence and various convergent measures of Negative Androcentrism. A structural model that the data fit well indicated a latent protective LH strategy trait predicted decreased negative androcentrism. This trait fully mediated the relationship between participant biological sex and androcentrism. We suggest that slow LH strategy may inhibit negative attitudes toward women because of relatively decreased intrasexual competition and intersexual conflict among slow LH strategists. DOI: 10.2458/azu_jmmss.v4i1.17774

  16. Aerodigitalni senzori - LH Systems ADS 40 / Airborne digital sensors: LH Systems ADS 40

    Directory of Open Access Journals (Sweden)

    Marko Pejić

    2004-01-01

    Full Text Available U radu su prezentovane osnove prikupljanja prostornih podataka metodom daljinske detekcije i klasičnim fotogrametrijskim metodom. Ukazano je na kompromis između dva metoda koji nudi digitalna aerokamera. Kompanija LH Systems proizvela je digitalnu aerokameru ADS 40 koja nudi sasvim nov koncept prikupljanja prostornih podataka. Sistem kamere obezbeđuje panhromatske i trodimenzionalne informacije koristeći tri CCD linije i opciono još pet linija iz multispektralnog opsega. Kamera skenira teren sa prostornom rezolucijom od 25 cm, površine od 300 kvadratnih kilometara, uz vreme trajanja leta koje je nešto kraće od jednog sata. / This paper presents basics of collecting spatial data with remote sensing and the classical photogrammetric method. A compromise between two methods, offered by a digital aero camera, is also suggested. The LH Systems has produced a new camera concept called Airborne Digital Sensor (ADS 40 which uses a new way of collecting spatial data. The camera system provides panchromatic and stereo information using three CCD lines and up to five more lines for multispectral imagery. The performance of the camera allows a three dimensional and multispectral image with a ground sample distance of 25 cm for an area of 300 square miles within a flight time shorter than one hour.

  17. Tracing of backward energy transfer from LH1 to LH2 in photosynthetic membranes grown under high and low irradiation.

    Directory of Open Access Journals (Sweden)

    Lanzani G.

    2013-03-01

    Full Text Available By introducing derivative transient absorption spectroscopy, we obtain rate constants for backward and forward energy transfer between LH1 and LH2 complexes in purple bacterial membranes. We find that backward energy transfer is strongly reduced in membranes grown under low irradiation conditions, compared to high light grown ones. We conclude that backward energy transfer is managed actively by the bacteria to avoid LH1 exciton deactivation under high irradiation conditions. The analytical method is generally applicable to excitonically coupled systems.

  18. Interdigital Line Antennas for Launching LH Waves in MST

    Science.gov (United States)

    Thomas, M. A.; Goetz, J. A.; Oliva, S. P.

    2002-11-01

    RF current drive has been proposed as a method for reducing the tearing fluctuations that are responsible for anomalous energy transport in the RFP. A system for launching lower hybrid slow waves at 800 MHz and n_||= 7.5 is now in operation on MST. The antenna is an enclosed interdigital line using λ/4 resonators with an opening in the cavity through which the wave is coupled to the plasma. A new antenna has been built incorporating several design improvements. These include larger vacuum feedthroughs, better impedance matching, internal instrumentation and improved directionality. Power handling is 3-4 times that of the original and continues to improve with conditioning. Further design improvements are underway to optimize impedance matching and damping rate along the traveling wave structure.

  19. Excitonic level structures of LH1 and LH2 of purple photosynthetic bacteria using an analytical approach

    Institute of Scientific and Technical Information of China (English)

    杨光参; 汪力; 杨国桢

    2003-01-01

    The excitonic level structure of a ring-like chain of dimers is discussed analytically in order to aid the understanding of the possible spectral properties of LH1 and LH2 of purple photosynthetic bacteria. Under the approximation of dipoledipole interaction between Bchls, the excitonic levels, bandwidths and energy gap between two Davydov subbands are expressed analytically in terms of interaction energies and configurational parameters of dipoles. Our model includes all the interactions between pigment molecules in the system. The oscillator strengths and circular dichroism (CD) for the excitonic states are also presented analytically. The simulated absorption and CD spectra of LH1 and LH2 complexes reproduce the main features of the measured results.

  20. Direct Visualization of Exciton Reequilibration in the LH1 and LH2 Complexes of Rhodobacter sphaeroides by Multipulse Spectroscopy

    Science.gov (United States)

    Cohen Stuart, Thomas A.; Vengris, Mikas; Novoderezhkin, Vladimir I.; Cogdell, Richard J.; Hunter, C. Neil; van Grondelle, Rienk

    2011-01-01

    The dynamics of the excited states of the light-harvesting complexes LH1 and LH2 of Rhodobacter sphaeroides are governed, mainly, by the excitonic nature of these ring-systems. In a pump-dump-probe experiment, the first pulse promotes LH1 or LH2 to its excited state and the second pulse dumps a portion of the excited state. By selective dumping, we can disentangle the dynamics normally hidden in the excited-state manifold. We find that by using this multiple-excitation technique we can visualize a 400-fs reequilibration reflecting relaxation between the two lowest exciton states that cannot be directly explored by conventional pump-probe. An oscillatory feature is observed within the exciton reequilibration, which is attributed to a coherent motion of a vibrational wavepacket with a period of ∼150 fs. Our disordered exciton model allows a quantitative interpretation of the observed reequilibration processes occurring in these antennas. PMID:21539791

  1. Direct Visualization of Exciton Reequilibration in the LH1 and LH2 Complexes of Rhodobacter sphaeroides by Multipulse Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stuart, Thomas A. Cohen [Free Univ. of Amsterdam (Netherlands); Vengris, Mikas [Vilnius Univ. (Lithuania); Novoderezhkin, Vladimir I. [A.N. Belozersky Inst. of Physico-Chemical Biology, Moscow State Univ. (Russia); Cogdell, Richard J. [Microbial Photosynthesis Laboratory, Glasgow Biomedical Research Centre, Univ. of Glasgow (United Kingdom); Hunter, C. Neil [Department of Molecular Biology and Biotechnology, Univ. of Sheffield, (United Kingdom); van Grondelle, Rienk [Free Univ. of Amsterdam (Netherlands)

    2011-01-01

    The dynamics of the excited states of the light-harvesting complexes LH1 and LH2 of Rhodobacter sphaeroides are governed, mainly, by the excitonic nature of these ring-systems. In a pump-dump-probe experiment, the first pulse promotes LH1 or LH2 to its excited state and the second pulse dumps a portion of the excited state. By selective dumping, we can disentangle the dynamics normally hidden in the excited-state manifold. We find that by using this multiple-excitation technique we can visualize a 400-fs reequilibration reflecting relaxation between the two lowest exciton states that cannot be directly explored by conventional pump-probe. An oscillatory feature is observed within the exciton reequilibration, which is attributed to a coherent motion of a vibrational wavepacket with a period of ~150 fs. Our disordered exciton model allows a quantitative interpretation of the observed reequilibration processes occurring in these antennas.

  2. Slow Pseudotachylites

    Science.gov (United States)

    Pec, M.; Stunitz, H.; Heilbronner, R.

    2011-12-01

    Tectonic pseudotachylites as solidified, friction induced melts are believed to be the only unequivocal evidence for paleo-earthquakes. Earthquakes occur when fast slip (1 - 3 m/s) propagates on a localized failure plane and are always related with stress drops. The mechanical work expended, together with the rock composition and the efficiency of thermal dissipation, controls whether the temperature increase on a localized slip plane will be sufficient to induce fusion. We report the formation of pseudotachylites during steady-state plastic flow at slow bulk shear strain rates (~10^-3 to ~10^-5 /s corresponding to slip rates of ~10^-6 to ~10^-8 m/s) in experiments performed at high confining pressures (500 MPa) and temperatures (300°C) corresponding to a depth of ~15 km. Crushed granitioid rock (Verzasca gneiss), grain size ≤ 200 μm, with 0.2 wt% water added was placed between alumina forcing blocks pre-cut at 45°, weld-sealed in platinum jackets and deformed with a constant displacement rate in a solid medium deformation apparatus (modified Griggs rig). Microstructural observations show the development of a S-C-C' fabric with C' slip zones being the dominant feature. Strain hardening in the beginning of the experiment is accompanied with compaction which is achieved by closely spaced R1 shears pervasively cutting the whole gouge zone and containing fine-grained material (d 10) are localized in less densely spaced, ~10 μm thick C'-C slip zones which develop predominantly in feldspars and often contain micas. In TEM, they appear to have no porosity consisting of partly amorphous material and small crystalline fragments with the average grain size of 20 nm. After the peak strength, the samples weaken by ~20 MPa and continue deforming up to γ ~ 4 without any stress drops. Strain localization progresses in the C'-C slip zones and leads to the formation of pseudotachylites. Rough estimates of slip rates in the deforming slip zones are 2 to 4 orders of magnitude

  3. Cetrorelix suppresses the preovulatory LH surge and ovulation induced by ovulation-inducing factor (OIF present in llama seminal plasma

    Directory of Open Access Journals (Sweden)

    Letelier Claudia

    2011-05-01

    Full Text Available Abstract Background The purpose of the study was to determine if the effect of llama OIF on LH secretion is mediated by stimulation of the hypothalamus or pituitary gland. Methods Using a 2-by-2 factorial design to examine the effects of OIF vs GnRH with or without a GnRH antagonist, llamas with a growing ovarian follicle greater than or equal to 8 mm were assigned randomly to four groups (n = 7 per group and a pre-treated with 1.5 mg of GnRH antagonist (cetrorelix acetate followed by 1 mg of purified llama OIF, b pre-treated with 1.5 mg of cetrorelix followed by 50 micrograms of GnRH, c pre-treated with a placebo (2 ml of saline followed by 1 mg of purified llama OIF or d pre-treated with a placebo (2 ml of saline followed by 50 micrograms of GnRH. Pre-treatment with cetrorelix or saline was given as a single slow intravenous dose 2 hours before intramuscular administration of either GnRH or OIF. Blood samples for LH measurement were taken every 15 minutes from 1.5 hours before to 8 hours after treatment. The ovaries were examined by ultrasonography to detect ovulation and CL formation. Blood samples for progesterone measurement were taken every-other-day from Day 0 (day of treatment to Day 16. Results Ovulation rate was not different (P = 0.89 between placebo+GnRH (86% and placebo+OIF groups (100%; however, no ovulations were detected in llamas pre-treated with cetrorelix. Plasma LH concentrations surged (P Conclusion Cetrorelix (GnRH antagonist inhibited the preovulatory LH surge induced by OIF in llamas suggesting that LH secretion is modulated by a direct or indirect effect of OIF on GnRH neurons in the hypothalamus.

  4. Momentum and heat transfer from lower hybrid antennas to the tokamak edge plasma

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, V.; Goniche, M.; Gunn, J.; Petrzilka, V

    2001-02-01

    The momentum and heat transfer from the Lower Hybrid (LH) grill electric field to tokamak edge plasma are derived within the framework of quasi-linear theory. Results are supported by test electron simulations. An LH power loss of the order of 1- 5% of total radiated power is found to occur in an interaction layer of the size of about 0.3 cm in the radial direction limited by electron Landau damping of the LH slow wave. The underlying electron distribution function describing fast electrons generated in both the parallel and anti-parallel (to{sup {yields}} B{sub 0}) directions is approximated by a sum of drifting Maxwellian with and <{delta}v{sup 2}{sub II} > determined here from the test particle simulations. Non-zero momentum transfer from the antenna field not only leads to fast electron beam formation discussed earlier [V. Fuchs, et al., Phys. Plasmas 3, 4023 (1996)], but also causes charge separation in front of the antenna [V. Petrzilka et al., Czech. Journ. Phys. S3, 127 (1999)]. The resulting electric field is calculated for electrons in equilibrium with the ambient plasma an terms which are likely to modify the ion dynamics are identified. (authors)

  5. ASASSN-15lh: The Most Luminous Supernova Ever Discovered

    CERN Document Server

    Dong, Subo; Prieto, J L; Jha, S W; Stanek, K Z; Holoien, T W -S; Kochanek, C S; Thompson, T A; Morrell, N; Thompson, I B; Basu, U; Beacom, J F; Bersier, D; Brimacombe, J; Brown, J S; Chen, Ping; Conseil, E; Danilet, A B; Falco, E; Grupe, D; Kiyota, S; Masi, G; Nicholls, B; Olivares, F; Pignata, G; Pojmanski, G; Simonian, G V; Szczygiel, D M; Wozniak, P R

    2015-01-01

    We report the discovery and early evolution of ASASSN-15lh, the most luminous supernova ever found. At redshift z=0.2326, ASASSN-15lh reached an absolute magnitude of M_{u,AB} ~ -23.5 and bolometric luminosity L_bol ~ 2.2x10^45 ergs/s, which is >~ 2 times more luminous than any previously known supernova. Its spectra match the hydrogen-poor sub-class of super-luminous supernovae (SLSNe-I), whose energy sources and progenitors are poorly understood. In contrast to known SLSNe-I, most of which reside in star-forming, dwarf galaxies, its host appears to be a luminous galaxy (M_V ~ -22; M_K ~ -25.1) with little star formation. In the two months since its first detection, ASASSN-15lh has radiated ~7.5x10^51 ergs, challenging the popular magnetar model for the engine of SLSNe-I.

  6. Application of ovine luteinizing hormone (LH) radioimmunoassay in the quantitation of LH in different mammalian species. [/sup 125/I tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Millar, R.P.; Aehnelt, C.

    1977-09-01

    A sensitive double antibody radioimmunoassay has been developed for measuring luteinizing hormone (LH) in various African mammalian species, using rabbit anti-ovine LH serum (GDN 15) and radioiodinated rat LH or ovine LH. Serum and pituitary homogenates from some African mammals (hyrax, reedbuck, sable, impala, tsessebe, thar, spring-hare, ground squirrel and cheetah, as well as the domestic sheep, cow and horse and laboratory rat and hamster) produced displacement curves parallel to that of the ovine LH standards. The specificity of the assay was examined in detail for one species, the rock hyrax. Radioimmunoassay and bioassay estimates of LH in hyrax pituitaries containing widely differing quantities of pituitary hormones were similar. In sexually active male hyrax mean plasma LH was 12.1 ng/ml and pituitary LH 194 ..mu..g/gland, but in sexually quiescent hyrax mean plasma LH was 2.4 ng/ml and mean pituitary LH 76 ..mu..g/gland. Intravenous injection of 10 ..mu..g of luteinizing hormone releasing hormone increased mean LH levels in hyrax from 0.9 ng/ml to 23.2 ng/ml by 30 min. Conversely, im injection of 250 ..mu..g testosterone induced a fall in LH levels in male hyrax from 1.7 ng/ml to 0.7 ng/ml 6 h after administration. Although the specificity of the assay for quantitating plasma LH in other species was not categorically established, there was a good correlation between plasma LH concentration and reproductive state in the bontebok, impala, spring-hare, thar, cheetah, domestic horse and laboratory rat, suggesting the potential use of the antiserum in quantitating LH in a variety of mammalian species.

  7. Role of fast waves in the central deposition of lower hybrid power

    Science.gov (United States)

    Heikkinen, J. A.; Tala, T. J. J.; Pättikangas, T. J. H.; Piliya, A. D.; Saveliev, A. N.; Karttunen, S. J.

    1999-10-01

    In tokamaks, lower hybrid (LH) waves are routinely used for current drive and heating of plasmas. The LH waves have two modes of propagation that are called the slow and the fast wave. Usually, the lower hybrid waves are launched as slow waves into a tokamak, but during the propagation part of the wave power can be transformed to fast waves. General characteristics of the mode transformation of slow waves to fast waves are first investigated with a simple quasitoroidal ray-tracing model. Next, the effect of mode transformed LH power on the deposition profiles in a JET-like tokamak is analysed by using the fast ray-tracing code FRTC. When the launched spectrum is at small values of the toroidal refractive index (1.6 icons/Journals/Common/lesssim" ALT="lesssim" ALIGN="TOP"/> nicons/Journals/Common/phi" ALT="phi" ALIGN="TOP"/>0 icons/Journals/Common/lesssim" ALT="lesssim" ALIGN="TOP"/> 2.0), the contribution of the fast wave to the deposited power is found to be significant and responsible for most of the absorption at the centre. When nicons/Journals/Common/phi" ALT="phi" ALIGN="TOP"/>0 is large (nicons/Journals/Common/phi" ALT="phi" ALIGN="TOP"/>0 icons/Journals/Common/gtrsim" ALT="gtrsim" ALIGN="TOP"/> 2.2), the effect of the mode transformed fast waves is small or negligible. At modest central densities (ne0 ~ 0.5 × 1020 m-3), the contribution of the fast wave to the power deposition can be more than 50% in the plasma centre. In consequence, the significant amount of wave energy absorbed in the fast mode must be carefully taken into account in modelling LH current drive experiments in the future. At low central densities (ne0 icons/Journals/Common/lesssim" ALT="lesssim" ALIGN="TOP"/> 0.3 × 1020 m-3), practically no absorption of fast waves occurs.

  8. FROM SLOW FOOD TO SLOW TOURISM

    Directory of Open Access Journals (Sweden)

    Bac Dorin Paul

    2014-12-01

    Full Text Available One of the effects of globalization is the faster pace of our lives. This rhythm can be noticed in all aspects of life: travel, work, shopping, etc. and it has serious negative effects. It has become common knowledge that stress and speed generate serious medical issues. Food and eating habits in the modern world have taken their toll on our health. However, some people took a stand and argued for a new kind of lifestyle. It all started in the field of gastronomy, where a new movement emerged – Slow Food, based on the ideas and philosophy of Carlo Petrini. Slow Food represents an important adversary to the concept of fast food, and is promoting local products, enjoyable meals and healthy food. The philosophy of the Slow Food movement developed in several directions: Cittaslow, slow travel and tourism, slow religion and slow money etc. The present paper will account the evolution of the concept and its development during the most recent years. We will present how the philosophy of slow food was applied in all the other fields it reached and some critical points of view. Also we will focus on the presence of the slow movement in Romania, although it is in a very early stage of development. The main objectives of the present paper are: to present the chronological and ideological evolution of the slow movement; to establish a clear separation of slow travel and slow tourism, as many mistake on for the other; to review the presence of the slow movement in Romania. Regarding the research methodology, information was gathered from relevant academic papers and books and also from interviews and discussions with local entrepreneurs. The research is mostly theoretical and empirical, as slow food and slow tourism are emerging research themes in academic circles.

  9. PERFORMANCE EVALUATION OF LOX AND LH2 TURBOPUMP TURBINES FOR A 10 TON THRUST LOX/LH2 ROCKET ENGINE

    OpenAIRE

    HASHIMOTO, Ryohei; Kamijo, Kenjiro; Watanabe, Yoshiaki; Hasegawa, Satoshi; Fujita, Toshihiko; 橋本, 亮平; 上絛, 謙二郎; 渡辺, 義明; 長谷川, 敏; 藤田, 敏彦

    1981-01-01

    The aerodynamic performance evaluation of the pump-drive turbines for a 10 ton thrust liquid oxygen and liquid hydrogen (LOX and LH2) gas generator cycle propulsion system, which has dual-shaft series turbines, was tested mainly using cold nitrogen gas. At design equivalent speed and pressure ratio, the LOX turbine static efficiency was about 35 percent compared to the design value of 32.8 percent. The LH2 turbine static efficiency was very close to the design value of 45 percent. Equivalent ...

  10. Astronomy. ASASSN-15lh: A highly super-luminous supernova.

    Science.gov (United States)

    Dong, Subo; Shappee, B J; Prieto, J L; Jha, S W; Stanek, K Z; Holoien, T W-S; Kochanek, C S; Thompson, T A; Morrell, N; Thompson, I B; Basu, U; Beacom, J F; Bersier, D; Brimacombe, J; Brown, J S; Bufano, F; Chen, Ping; Conseil, E; Danilet, A B; Falco, E; Grupe, D; Kiyota, S; Masi, G; Nicholls, B; Olivares E, F; Pignata, G; Pojmanski, G; Simonian, G V; Szczygiel, D M; Woźniak, P R

    2016-01-15

    We report the discovery of ASASSN-15lh (SN 2015L), which we interpret as the most luminous supernova yet found. At redshift z = 0.2326, ASASSN-15lh reached an absolute magnitude of Mu ,AB = -23.5 ± 0.1 and bolometric luminosity Lbol = (2.2 ± 0.2) × 10(45) ergs s(-1), which is more than twice as luminous as any previously known supernova. It has several major features characteristic of the hydrogen-poor super-luminous supernovae (SLSNe-I), whose energy sources and progenitors are currently poorly understood. In contrast to most previously known SLSNe-I that reside in star-forming dwarf galaxies, ASASSN-15lh appears to be hosted by a luminous galaxy (MK ≈ -25.5) with little star formation. In the 4 months since first detection, ASASSN-15lh radiated (1.1 ± 0.2) × 10(52) ergs, challenging the magnetar model for its engine. Copyright © 2016, American Association for the Advancement of Science.

  11. Risk Assessment and Scaling for the SLS LH2 ET

    Science.gov (United States)

    Hafiychuk, Halyna; Ponizovskaya-Devine, Ekaterina; Luchinsky, Dmitry; Khasin, Michael; Osipov, Viatcheslav V.; Smelyanskiy, Vadim N.

    2012-01-01

    In this report the main physics processes in LH2 tank during prepress and rocket flight are studied. The goal of this investigation is to analyze possible hazards and to make risk assessment in proposed LH2 tank designs for SLS with 5 engines (the situation with 4 engines is less critical). For analysis we use the multinode model (MNM) developed by us and presented in a separate report and also 3D ANSYS simulations. We carry out simulation and theoretical analysis the physics processes such as (i) accumulation of bubbles in LH2 during replenish stage and their collapsing in the liquid during the prepress; (ii) condensation-evaporation at the liquid-vapor interface and tank wall, (iv) heating the liquid near the interface and wall due to condensation and environment heat, (v) injection of hot He during prepress and of hot GH2 during flight, (vi) mixing and cooling of the injected gases due to heat transfer between the gases, liquid and the tank wall. We analyze the effects of these physical processes on the thermo- and fluid gas dynamics in the ullage and on the stratification of temperature in the liquid and assess the associated hazards. A special emphasize is put on the scaling predictions for the larger SLS LH2 tank.

  12. 掺混型缓/控释肥对杂交晚稻产量的影响%Effect of slow/controlled-release fertilizer on yield of late hybrid rice

    Institute of Scientific and Technical Information of China (English)

    王玉军; 邹应斌; 张夫道

    2009-01-01

    Field experiment was trialed to study effect of slow/controlled-release fertilizer on yield of late hybrid rice and CK1 was no fertilizer and CK2 was same amount of NPK. The results showed that yields of slow/controlled-release fertilizer treatments were higher than NPK treatment Compared to NPK treatment, in Changsha normal fertility paddy soil, the effect was best for 35%polyethylene alcohol mixing for adhesive (CF2) felted fertilizer+65% wasted foam (PS) mixed and coated fertilizer (for short CF2 + PS) that increased yield by 27. 68% , and the second was 35% kaolin-polyesterfelted fertilizer + 65% PS coated fertilizer and yield increased by 24. 70%. In Ningxiang low fertility paddy soil, the effect was best for 35% kaolin-polyesterfelted fertilizer +65% PS coated fertilizer and yield increased by 37. 25% , effect of increasing yield for treatments in Ningxiang were better than that of treatments in Changsha. The lower fertility of soil and the higher of increasing rate of fertilizer. Compared to NPK treatment, yield was higher when amount of blend slow release fertilizer decreased by 20%. According to crop grow period, the effects of blending slow release fertilizer with different nutrient release period in some percentage were better.%采用田间小区试验,以不施肥(CK1)和施用等量NPK化肥(CK2)为对照,研究掺混型缓/控释肥对水稻产量的影响.结果表明,各缓释肥处理的产量均高于等量NPK处理.其中,在长沙点中肥力水稻土上,35%聚乙烯醇混聚物(CF2)胶结复混肥+65%废弃泡沫塑料(PS)混聚物包膜复混肥(简称CF2+PS)效果最好,比等量NPK处理增产27.68%,其次是35%高岭土-聚酯胶结肥+65%PS包膜肥,比等量NPK处理增产24.70%;在宁乡点低肥力水稻土上,35%高岭土-聚酯胶结肥+65%PS包膜肥处理效果最好,比等量NPK处理增产37.25%;宁乡试验点各施肥处理的增产效果均高于长沙点,说明土壤肥力越低,肥料的增产率越高;减少20%掺

  13. Extension of Light-Harvesting Ability of Photosynthetic Light-Harvesting Complex 2 (LH2) through Ultrafast Energy Transfer from Covalently Attached Artificial Chromophores.

    Science.gov (United States)

    Yoneda, Yusuke; Noji, Tomoyasu; Katayama, Tetsuro; Mizutani, Naoto; Komori, Daisuke; Nango, Mamoru; Miyasaka, Hiroshi; Itoh, Shigeru; Nagasawa, Yutaka; Dewa, Takehisa

    2015-10-14

    Introducing appropriate artificial components into natural biological systems could enrich the original functionality. To expand the available wavelength range of photosynthetic bacterial light-harvesting complex 2 (LH2 from Rhodopseudomonas acidophila 10050), artificial fluorescent dye (Alexa Fluor 647: A647) was covalently attached to N- and C-terminal Lys residues in LH2 α-polypeptides with a molar ratio of A647/LH2 ≃ 9/1. Fluorescence and transient absorption spectroscopies revealed that intracomplex energy transfer from A647 to intrinsic chromophores of LH2 (B850) occurs in a multiexponential manner, with time constants varying from 440 fs to 23 ps through direct and B800-mediated indirect pathways. Kinetic analyses suggested that B800 chromophores mediate faster energy transfer, and the mechanism was interpretable in terms of Förster theory. This study demonstrates that a simple attachment of external chromophores with a flexible linkage can enhance the light harvesting activity of LH2 without affecting inherent functions of energy transfer, and can achieve energy transfer in the subpicosecond range. Addition of external chromophores, thus, represents a useful methodology for construction of advanced hybrid light-harvesting systems that afford solar energy in the broad spectrum.

  14. Cold and Slow Molecular Beam

    CERN Document Server

    Lu, Hsin-I; Wright, Matthew J; Patterson, Dave; Doyle, John M

    2011-01-01

    Employing a two-stage cryogenic buffer gas cell, we produce a cold, hydrodynamically extracted beam of calcium monohydride molecules with a near effusive velocity distribution. Beam dynamics, thermalization and slowing are studied using laser spectroscopy. The key to this hybrid, effusive-like beam source is a "slowing cell" placed immediately after a hydrodynamic, cryogenic source [Patterson et al., J. Chem. Phys., 2007, 126, 154307]. The resulting CaH beams are created in two regimes. One modestly boosted beam has a forward velocity of vf = 65 m/s, a narrow velocity spread, and a flux of 10^9 molecules per pulse. The other has the slowest forward velocity of vf = 40 m/s, a longitudinal temperature of 3.6 K, and a flux of 5x10^8 molecules per pulse.

  15. LOX/LH2 vane pump for auxiliary propulsion systems

    Science.gov (United States)

    Hemminger, J. A.; Ulbricht, T. E.

    1985-01-01

    Positive displacement pumps offer potential efficiency advantages over centrifugal pumps for future low thrust space missions. Low flow rate applications, such as space station auxiliary propulsion or dedicated low thrust orbiter transfer vehicles, are typical of missions where low flow and high head rise challenge centrifugal pumps. The positive displacement vane pump for pumping of LOX and LH2 is investigated. This effort has included: (1) a testing program in which pump performance was investigated for differing pump clearances and for differing pump materials while pumping LN2, LOX, and LH2; and (2) an analysis effort, in which a comprehensive pump performance analysis computer code was developed and exercised. An overview of the theoretical framework of the performance analysis computer code is presented, along with a summary of analysis results. Experimental results are presented for pump operating in liquid nitrogen. Included are data on the effects on pump performance of pump clearance, speed, and pressure rise. Pump suction performance is also presented.

  16. LH transition characteristics due to bipolar losses in tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Toda, Shinichiro [Interdisciplinary Graduate School of Engineering Sciences, Kyushu Univ., Kasuga, Fukuoka (Japan); Yagi, Masatoshi; Itoh, Sanae-I.

    1998-10-01

    The L/H transition theory is extended based on the electrostatic bifurcation. We study the bipolar losses which have not been examined as the transition mechanisms yet and investigate the L/H transition characteristics. The comparison study with the experimental results is also done. It is found that the equation of motions has the solutions with various hysteresis types of electrostatic bifurcation phenomena when the mechanisms of bipolar losses are considered. The dependences of the particle flux and the diffusivity on the thermodynamic force in the presence of the electric field are examined. ELMs (Edge Localizes Modes) phenomena which are typical in the H-mode are studied. The model equation is newly extended to include the effect of the electric field shear in addition to the electric field shear. This model is also extended to the dynamic model which includes the temporal evolution of the density from the static model with the hysteresis characteristics. (author)

  17. Levels of FSH, LH and testosterone, and sperm DNA fragmentation.

    Science.gov (United States)

    Wdowiak, Artur; Raczkiewicz, Dorota; Stasiak, Magdalena; Bojar, Iwona

    2014-01-01

    Having an offspring is the most important human biological goal, which is necessary for survival of the human species. Lack of offspring is a phenomenon concerning approximately 15% of married couples in Poland. In a half of the cases, a causative agent is the male factor infertility problem. There is evidence that certain male fertility problems are related with disorders of the process of spermatogenesis. The course of normal spermatogenesis depends on proper pituitary secretion of folliculostimulin (FSH), luteinizing hormone (LH), as well as testicular secretion of testosterone. It is considered that in approximately 20% of patients with idiopathic infertility an elevated level of sperm DNA fragmentation may be the cause of failure in reproduction. The objective of the present study was determination of the relationship between FSH, LH and testosterone levels, and the occurrence of sperm DNA fragmentation. The present study was conducted in the year 2012 in the Non-Public Health Care Unit 'Ovum Reproduction and Andrology' in Lublin, and covered 186 men treated for infertility. For inclusion into the study group we qualified males aged 25-35, who have been treated for infertility for more than 1 year, with no pathological features observed in the female partner. The structure of sperm chromatin was evaluated using the technique of flow cytometry-Sperm Chromatin Structure assay (SCSA). The result of the examination was a sperm DNA Fragmentation Index (DFI), i.e., the percentage of sperm with DNA lesions (DNA fragmentation). A morning blood sample (5 mL volume) was obtained and sent to an authorized laboratory to assess serum levels of testosterone, LH and FSH. An intensified sperm DNA fragmentation co-occurred with both extremely low and extremely high levels of FSH and LH. Sperm DNA fragmentation was negatively correlated with testosterone level.

  18. Towards a Physics-Based L-H Transition Model

    Science.gov (United States)

    Schmitz, L.; Rhodes, T. L.; Neiser, T.; Bardoczi, L.; Jenko, F.; Zeng, L.; Gohil, P.; Chrystal, C.; Grierson, B. A.; Eldon, D.; Yan, Z.; McKee, G. R.; Boedo, J.

    2016-10-01

    L-mode turbulence properties, collisionality, and ion transport fluxes across the separatrix are shown to determine the pre-transition ion poloidal and diamagnetic L-mode edge flow and the shear flow amplification triggering the L-H transition. L-mode ion thermal fluxes increase with density above the power threshold minimum, and are higher in hydrogen than in deuterium plasmas. The long-range toroidal ExB flow correlation at the L-H transition trigger time is observed to peak at intermediate plasma density around the L-H power threshold minimum, and is higher in D-plasmas in comparison to H-plasmas, indicating a possible link between trigger physics and power threshold. The turbulence-driven poloidal ion flow is found decisive for initial turbulence suppression, with a Reynolds stress gradient sufficiently large to account for the measured poloidal flow acceleration in the plateau collisionality. Supported by the US DOE under DE-FG02-08ER54984, DE-FC02-04ER54698, DE-AC02-09CH11466, DE-FG02-89ER53296, DE-FG02-07ER54917.

  19. Parallel Electron Force Balance and the L-H Transition

    Science.gov (United States)

    Stoltzfus-Dueck, T.; Diallo, A.; Zweben, S.; Banerjee, S.

    2016-10-01

    In a popular description of the L-H transition, energy transfer to the mean flows directly depletes turbulence fluctuation energy, resulting in suppression of the turbulence and a corresponding transport bifurcation. However, electron parallel force balance couples nonzonal velocity fluctuations with electron pressure fluctuations on rapid timescales, comparable with the electron transit time. For this reason, energy in the nonzonal velocity stays in a fairly fixed ratio to electron thermal free energy, at least for frequency scales much slower than electron transit. In order for direct depletion of the energy in turbulent fluctuations to cause the L-H transition, energy transfer via Reynolds stress must therefore drain enough energy to significantly reduce the sum of the free energy in nonzonal velocities and electron pressure fluctuations. At low k⊥, the electron thermal free energy is much larger than the energy in nonzonal velocities, posing a stark challenge for this model of the L-H transition. Work supported by U.S. DoE contract #DE-AC02-09CH11466.

  20. SALT Spectroscopy of ASASSN-15lh: The Most Luminous Supernova?

    Science.gov (United States)

    Court, Travis; Camacho, Yssavo; Dettman, Kyle; Jha, Saurabh W.

    2017-01-01

    In August 2015, ASASSN-15lh was discovered as the most luminous supernova (SN) ever found (Dong et al. 2016), more than twice as bright as other so-called super-luminous supernovae (SLSN). However, the spectral evolution of the transient is unlike any known supernova. To better understand this object, we have observed ASASSN-15lh with the Southern African Large Telescope (SALT). We obtained spectroscopic data in July 2016 and reduced and calibrated the spectrum for comparison with other supernovae. The new pectrum did not show strong supernova features and was dominated by light from the host galaxy. We used this late spectrum as a galaxy template, subtracting it from earlier data. However, we still find that ASASSN-15lh does not clearly resemble any known supernova. Either it is unique, or perhaps an alternate explanation is needed (e.g., a tidal disruption event; Leloudas et al. 2016). This Research Experience for Undergraduates project in the Department of Physics and Astronomy at Rutgers University has been supported by funding from National Science Foundation grants PHY-1263280 and PHY-1560077.

  1. Suboptimal response to GnRHa long protocol is associated with a common LH polymorphism

    DEFF Research Database (Denmark)

    Alviggi, C; Clarizia, R; Pettersson, K;

    2011-01-01

    The aim of this observational preliminary trial was to estimate the association between the most common polymorphism of LH (LH-β variant: v-βLH), with different profiles of ovarian response to recombinant human FSH (rhFSH). A total of 60 normogonadotrophic patients undergoing a gonadotrophin-rele...

  2. An electrostatic particle-in-cell model for a lower hybrid grill

    Energy Technology Data Exchange (ETDEWEB)

    Rantamaeki, K

    1998-07-01

    In recent lower hybrid (LH) current drive experiments, generation of hot spots and impurities in the grill region have been observed on Tore Supra and Tokamak de Varennes (TdeV). A possible explanation is the parasitic absorption of the LH power in front of the grill. In parasitic absorption, the short-wavelength part of the lower hybrid spectrum can resonantly interact with the cold edge electrons. In this work, the absorption of the LH waves and the generation of fast electrons near the waveguide mouth is investigated with a new tool in this context: particle-in-cell (PIC) simulations. The advantage of this new method is that the electric field is calculated self-consistently. The PIC simulations also provide the key parameters for the hot spot problem: the absorbed power, the radial deposition profiles and the absorption length. A grill model has been added to the 2d3v PIC code XPDP2. Two sets of simulations were made. The first simulations used a phenomenological grill model. Strong absorption in the edge plasma was obtained. About 5% of the coupled power was absorbed within 1.7 mm in the case with fairly large amount of power in the modes with large parallel refractive index. Consequently, a rapid generation of fast electrons took place in the same region. In order to model experiments with realistic wave spectra, the PIC code was coupled to the slow wave antenna coupling code SWAN. The absorption within 1.7 mm in front of the grill was found to be between 2 and 5%. In the short time of a few wave periods, part of the initially thermal electrons (T{sub e} = 100 eV) were accelerated to velocities corresponding to a few keV. (orig.)

  3. Assessment of the LH wave for demo in pulsed and steady state scenario

    Energy Technology Data Exchange (ETDEWEB)

    Cardinali, A.; Barbato, E.; Castaldo, C.; Cesario, R.; Marinucci, M.; Ravera, G. L.; Tuccillo, A. A. [Associazione Euratom-ENEA sulla Fusione, C.R. Frascati, Via Enrico Fermi, 45 00044, Frascati, Roma (Italy); Ceccuzzi, S. [Associazione Euratom-ENEA sulla Fusione, C.R. Frascati, Via Enrico Fermi, 45 00044, Frascati, Roma, Italy and Department of Engineering, Roma Tre University, Via Vito Volterra, 62, 00146, Roma (Italy); Mirizzi, F.; Panaccione, L. [Consorzio CREATE, Universita degli Studi di Napoli Federico II, Via Claudio 21, 80125, Napoli (Italy); Santini, F.; Schettini, G. [Department of Engineering, Roma Tre University, Via Vito Volterra, 62, 00146, Roma (Italy)

    2014-02-12

    The Lower Hybrid Current Drive (LHCD) has been analysed in DEMO tokamak plasma in the 'pulsed and steady state regime' considering two plasma scenarios characterized, respectively, by flat density profile and peaked density profiles. We have obtained LH deposition profiles in cases of neglecting the effect of spectral broadening produced by PI at the edge. By comparing the Power Deposition Profiles for both DEMO scenarios ('flat' and 'peaked'), the SOL of DEMO does not play any role in the absorption of the LH wave. In all cases the deposition is localized inside the separatrix layer r/a≤1. By lowering the parallel wave-number peak of the power spectrum from 1.8 to 1.5, the accessibility condition in both case prevents the power from reaching the deposition layer apart from a small fraction which pertains to the higher n∥ of the power spectrum. The spectrum centred at 1.8 is suggested to be useful in DEMO. More realistically, as supported by available data of LHCD in a wide range of operating densities, the effect of parametric decay instability (PDI) can produce a spectral broadening which should be included in the simulations. Further studies would be necessary for assessing the temperature profiles in the SOL at reactor-graded conditions. This is because, if the SOL temperature is at least of the order of 50 to 100 eV, the effect of PDI broads the spectrum up to n∥≤10, and the deposition profile is slightly wider but not much shifted outwards.

  4. Probability of statistical L-H transition in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Sanae-I. [Kyushu Univ., Research Institute for Applied Mechanics, Kasuga, Fukuoka (Japan); Itoh, Kimitaka; Toda, Shinichiro [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2002-08-01

    A statistical model of bifurcation of radial electric field E{sub r} is analyzed in relation with L-H transitions of tokamaks. A noise from micro fluctuations leads to random noise for E{sub r}. The transition of E{sub r} occurs in a probabilistic manner. Probability density function and ensemble average of E{sub r} are obtained, when hysteresis of E{sub r} exists. Forward- and backward-transition probabilities are calculated. The phase boundary is shown. Due to the suppression of turbulence by E{sub r} shear, the boundary deviates from the Maxwell's construction rule. (author)

  5. Spatial structure of compound dither in L/H transition

    Energy Technology Data Exchange (ETDEWEB)

    Toda, Shinichiro; Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan); Itoh, Sanae I.; Yagi, Masatoshi [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Fukuyama, Atsushi [Kyoto Univ. (Japan). Dept. of Nuclear Engineering

    2000-03-01

    To study the plasma evolution and spatial structure at the L/H transition, the double hysteresis is examined by use of the 1-dimensional transport model equations. Three mechanisms for the bipolar losses, i.e., the loss cone loss, collisional bulk viscosity loss of ions and the anomalous loss are simultaneously retained. Five-fold multiple bifurcations are found to exist at the plasma edge, similar to the previous 0-dimensional study. Double hysteresis causes a self-generated oscillation, which is attributed to the compound dither, a kind of ELMs. Spatio-temporal evolution of the compound dither is analyzed. (author)

  6. Effect of metal nanoparticles on energy spectra and optical properties of peripheral light-harvesting LH2 complexes from photosynthetic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Goliney, I.Yu., E-mail: igoliney@kinr.kiev.ua [Institute for Nuclear Research, National Academy of Science of Ukraine, 47 Nauki pr., 03680 Kyiv (Ukraine); Sugakov, V.I. [Institute for Nuclear Research, National Academy of Science of Ukraine, 47 Nauki pr., 03680 Kyiv (Ukraine); Valkunas, L. [Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius (Lithuania); Department of Theoretical Physics, Vilnius University, Sauletekio 9, Build. 3, 10222 Vilnius (Lithuania); Vertsimakha, G.V. [Institute for Nuclear Research, National Academy of Science of Ukraine, 47 Nauki pr., 03680 Kyiv (Ukraine)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Excitons of light-harvesting complexes (LH2) hybridize with plasmon modes. Black-Right-Pointing-Pointer Light absorption of LH2 is enhanced by a metal nanoparticle. Black-Right-Pointing-Pointer Using nanoshells allows reaching resonance between molecular and plasmons. Black-Right-Pointing-Pointer Metal nanoparticles introduce additional channel of excitation decay. Black-Right-Pointing-Pointer Light-harvesting may gain from the proper positioning of nanoshells. -- Abstract: The paper explores the theoretical possibility of affecting optical spectra and the quantum yield of the energy transfer in the peripheral light-harvesting complexes (LH2) from photosynthetic bacteria by placing a metal nanoparticle or a nanoshell nearby. An increased probability of the excitonic transition in the LH2 arises due to the borrowing of the oscillator strength from surface plasmons of the metal particle or the nanoshell. While both absorption and quenching of the excitations increase in the vicinity to a metal nanoparticle, having opposite effects, the total yield of the excitation transfer to reaction centers is shown to grow in the certain range of parameters.

  7. Too slow, for Milton

    OpenAIRE

    Armstrong, N.

    2011-01-01

    Too slow, for Milton was written in 2011, as part of a memorial project for Milton Babbitt. The piece borrows harmonies from Babbitt's Composition for 12 Instruments (harmonies which Babbitt had in turn borrowed from Schoenberg's Ode to Napoleon), but unfolds them as part of a musical texture characterised by repetition, resonance, and a slow rate of change. As Babbitt once told me that my music was 'too slow', this seemed an appropriately obstinate form of homage.

  8. Nonlinear lower hybrid modeling in tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Napoli, F.; Schettini, G. [Università Roma Tre, Dipartimento di Ingegneria, Roma (Italy); Castaldo, C.; Cesario, R. [Associazione EURATOM/ENEA sulla Fusione, Centro Ricerche Frascati (Italy)

    2014-02-12

    We present here new results concerning the nonlinear mechanism underlying the observed spectral broadening produced by parametric instabilities occurring at the edge of tokamak plasmas in present day LHCD (lower hybrid current drive) experiments. Low frequency (LF) ion-sound evanescent modes (quasi-modes) are the main parametric decay channel which drives a nonlinear mode coupling of lower hybrid (LH) waves. The spectrum of the LF fluctuations is calculated here considering the beating of the launched LH wave at the radiofrequency (RF) operating line frequency (pump wave) with the noisy background of the RF power generator. This spectrum is calculated in the frame of the kinetic theory, following a perturbative approach. Numerical solutions of the nonlinear LH wave equation show the evolution of the nonlinear mode coupling in condition of a finite depletion of the pump power. The role of the presence of heavy ions in a Deuterium plasma in mitigating the nonlinear effects is analyzed.

  9. The involvement of dopaminergic system on LH secretion Nelore heifers Sistema dopaminérgico na secreção de LH de novilhas Nelore

    Directory of Open Access Journals (Sweden)

    Silvia Helena Venturoli Perri

    2009-12-01

    Full Text Available The aim of this study was to evaluate the response of sulpiride administration (dopamine D2 antagonist, 0.59 m/kg body weight, s.c. and blood collected every 15 min for 10 h thereafter on Luteinizing Hormone (LH secretion in B. indicus pre-pubertal heifers at 8, 12 and 16 month of age. LH was quantified by RIA, sensitivity (0.039 ng/ml and CV (15.51%. In heifers given sulpiride treatment didn’t differ (P≥0.05 in LH concentration, total secretion area, peak total area, number of peaks, area of highest secretion peak and time to highest peak occurrence and maximum LH secretion, from control group. The results suggest absence of dopamine D2 antagonist effect on LH secretion in pre-pubertal Nellore heifers, didn’t neurotransmitter participating on sexual maturation.O presente trabalho foi realizado com o objetivo de investigar a variação na secreção do Hormônio Luteinizante (LH em resposta ao tratamento com sulpiride, antagonista de receptor (D2 dopaminérgico, com administração de 0,59mg/kg, s.c. e colheita de amostras de sangue a cada 15min, por 10h. Foram utilizadas 10 novilhas da raça Nelore pré-púberes, aos 8, 12 e 16 meses de idade. A concentração de LH foi quantificada por radioimunoensaio, e o coeficiente de variação intra, o interensaio e a sensibilidade dos ensaios de LH foram respectivamente de: 11,86%; 15,51%; 0,039ng/mL. O tratamento com sulpiride não diferiu na concentração média de LH, área total de secreção de LH e picos, número de picos, área do maior pico, tempo necessário ao aparecimento do maior pico de secreção de LH e amplitude máxima de LH, em comparação ao grupo controle. Os resultados indicam ausência de efeito da dopamina, através de receptores D2, durante a fase pré-púbere, em novilhas da raça Nelore, o que sinaliza a não participação como neurotransmissora na secreção de LH durante o processo de maturação sexual.

  10. The study of photo-induced ultrafast dynamics in light-harvesting complex LH2 of purple bacteria

    Institute of Scientific and Technical Information of China (English)

    LIU Wei-min; YAN Yong-li; LIU Kang-jun; XU Chun-he; QIAN Shi-xiong

    2006-01-01

    In this paper,we introduce the photo-induced ultrafast dynamics taking place in the peripheral light harvesting antenna LH2 from purple bacteria Rhodobacter sphaeroides by using absorption,fluorescence emission and ultrafast spectroscopic techniques.Three kinds of LH2 sampies,pH treated LH2 (complete removal of B800 pigments),carotenoid mutated LH2 (GM 309) and electrochemical oxidation treated LH2 were used in comparison with native LH2 to investigate the mechanism of photo-induced ultrafast energy transfer within the LH2 complex.

  11. DE-1 and COSMOS 1809 observations of lower hybrid waves excited by VLF whistler mode waves

    Science.gov (United States)

    Bell, T. F; Inan, U. S.; Lauben, D.; Sonwalkar, V. S.; Helliwell, R. A.; Sobolev, Ya. P.; Chmyrev, V. M.; Gonzalez, S.

    1994-01-01

    Past work demostrates that strong lower hybrid (LH) waves can be excited by electromagnetic whistler mode waves throughout large regions of the topside ionosphere and magnetosphere. The effects of the excited LH waves upon the suprathermal ion population in the topside ionosphere and magnetosphere depend upon the distribution of LH wave amplitude with wavelength lambda. The present work reports plasma wave data from the DE-1 and COSMOS 1809 spacecraft which suggests that the excited LH wave spectrum has components for which lambda less than or equal to 3.5 m when excitation occurs at a frequency roughly equal to the local lower hybrid resonance frequency. This wavelength limit is a factor of approximately 3 below that reported in past work and suggests that the excited LH waves can interact with suprathermal H(+) ions with energy less than or equal to 6 eV. This finding supports recent work concerning the heating of suprathermal ions above thunderstorm cells.

  12. The "Ram Effect": A "Non-Classical" Mechanism for Inducing LH Surges in Sheep.

    Science.gov (United States)

    Fabre-Nys, Claude; Chanvallon, Audrey; Dupont, Joëlle; Lardic, Lionel; Lomet, Didier; Martinet, Stéphanie; Scaramuzzi, Rex J

    2016-01-01

    During spring sheep do not normally ovulate but exposure to a ram can induce ovulation. In some ewes an LH surge is induced immediately after exposure to a ram thus raising questions about the control of this precocious LH surge. Our first aim was to determine the plasma concentrations of oestradiol (E2) E2 in anoestrous ewes before and after the "ram effect" in ewes that had a "precocious" LH surge (starting within 6 hours), a "normal" surge (between 6 and 28h) and "late» surge (not detected by 56h). In another experiment we tested if a small increase in circulating E2 could induce an LH surge in anoestrus ewes. The concentration of E2 significantly was not different at the time of ram introduction among ewes with the three types of LH surge. "Precocious" LH surges were not preceded by a large increase in E2 unlike "normal" surges and small elevations of circulating E2 alone were unable to induce LH surges. These results show that the "precocious" LH surge was not the result of E2 positive feedback. Our second aim was to test if noradrenaline (NA) is involved in the LH response to the "ram effect". Using double labelling for Fos and tyrosine hydroxylase (TH) we showed that exposure of anoestrous ewes to a ram induced a higher density of cells positive for both in the A1 nucleus and the Locus Coeruleus complex compared to unstimulated controls. Finally, the administration by retrodialysis into the preoptic area, of NA increased the proportion of ewes with an LH response to ram odor whereas treatment with the α1 antagonist Prazosin decreased the LH pulse frequency and amplitude induced by a sexually active ram. Collectively these results suggest that in anoestrous ewes NA is involved in ram-induced LH secretion as observed in other induced ovulators.

  13. Dimerization of human lysyl hydroxylase 3 (LH3) is mediated by the amino acids 541-547.

    Science.gov (United States)

    Heikkinen, Jari; Risteli, Maija; Lampela, Outi; Alavesa, Paula; Karppinen, Marjo; Juffer, André H; Myllylä, Raili

    2011-01-01

    Lysyl hydroxylases (LH), which catalyze the post-translational modifications of lysines in collagen and collagen-like proteins, function as dimers. However, the amino acids responsible for dimerization and the role of dimer formation in the enzymatic activities of LH have not yet been identified. We have localized the region responsible for the dimerization of lysyl hydroxylase 3 (LH3), a multifunctional enzyme of collagen biosynthesis, to a sequence of amino acids between the glycosyltransferase activity and the lysyl hydroxylase activity domains. This area is covered by amino acids 541-547 in human LH3, but contains no cysteine residues. The region is highly conserved among LH isoforms, and is also involved in the dimerization of LH1 subunits. Dimerization is required for the LH activity of LH3, whereas it is not obligatory for the glycosyltransferase activities. In order to determine whether complex formation can occur between LH molecules originating from different species, and between different LH isoforms, double expressions were generated in a baculovirus system. Heterocomplex formation between mouse and human LH3, between human LH1 and LH3 and between human LH2 and LH3 was detected by western blot analyses. However, due to the low amount of complexes formed, the in vivo function of heterocomplexes remains unclear. Copyright © 2010 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

  14. Effect of different FSH/LH ratios on superovulatory response and embryo yield in goats

    Directory of Open Access Journals (Sweden)

    G. Martemucci

    2011-03-01

    Full Text Available Previous studies carried out in sheep (Chupin et al., 1985 and in goats (Nowshari et al., 1995; Martemucci et al., 1996 have underlined the importance of both FSH and LH to induce a good superovulatory response, but the results on the LH amount necessary to give a higher ovulatory response and embryo production are rather contradictory. The aim of this study was to evaluate, in goats, the effect of 2 different FSH/LH ratios (1:1 vs 2:1 kept constant during the treatment, on ovulatory response and embryo production. Moreover, according to the FSH/LH ratio=2:1,.........

  15. Characterisation of the LH2 spectral variants produced by the photosynthetic purple sulphur bacterium Allochromatium vinosum.

    Science.gov (United States)

    Carey, Anne-Marie; Hacking, Kirsty; Picken, Nichola; Honkanen, Suvi; Kelly, Sharon; Niedzwiedzki, Dariusz M; Blankenship, Robert E; Shimizu, Yuuki; Wang-Otomo, Zheng-Yu; Cogdell, Richard J

    2014-11-01

    This study systematically investigated the different types of LH2 produced by Allochromatium (Alc.) vinosum, a photosynthetic purple sulphur bacterium, in response to variations in growth conditions. Three different spectral forms of LH2 were isolated and purified, the B800-820, B800-840 and B800-850 LH2 types, all of which exhibit an unusual split 800 peak in their low temperature absorption spectra. However, it is likely that more forms are also present. Relatively more B800-820 and B800-840 are produced under low light conditions, while relatively more B800-850 is produced under high light conditions. Polypeptide compositions of the three different LH2 types were determined by a combination of HPLC and TOF/MS. The B800-820, B800-840 and B800-850 LH2 types all have a heterogeneous polypeptide composition, containing multiple types of both α and β polypeptides, and differ in their precise polypeptide composition. They all have a mixed carotenoid composition, containing carotenoids of the spirilloxanthin series. In all cases the most abundant carotenoid is rhodopin; however, there is a shift towards carotenoids with a higher conjugation number in LH2 complexes produced under low light conditions. CD spectroscopy, together with the polypeptide analysis, demonstrates that these Alc. vinosum LH2 complexes are more closely related to the LH2 complex from Phs. molischianum than they are to the LH2 complexes from Rps. acidophila.

  16. Enhanced slow-wave EEG activity and thermoregulatory impairment following the inhibition of the lateral hypothalamus in the rat.

    Directory of Open Access Journals (Sweden)

    Matteo Cerri

    Full Text Available Neurons within the lateral hypothalamus (LH are thought to be able to evoke behavioural responses that are coordinated with an adequate level of autonomic activity. Recently, the acute pharmacological inhibition of LH has been shown to depress wakefulness and promote NREM sleep, while suppressing REM sleep. These effects have been suggested to be the consequence of the inhibition of specific neuronal populations within the LH, i.e. the orexin and the MCH neurons, respectively. However, the interpretation of these results is limited by the lack of quantitative analysis of the electroencephalographic (EEG activity that is critical for the assessment of NREM sleep quality and the presence of aborted NREM-to-REM sleep transitions. Furthermore, the lack of evaluation of the autonomic and thermoregulatory effects of the treatment does not exclude the possibility that the wake-sleep changes are merely the consequence of the autonomic, in particular thermoregulatory, changes that may follow the inhibition of LH neurons. In the present study, the EEG and autonomic/thermoregulatory effects of a prolonged LH inhibition provoked by the repeated local delivery of the GABAA agonist muscimol were studied in rats kept at thermoneutral (24°C and at a low (10°C ambient temperature (Ta, a condition which is known to depress sleep occurrence. Here we show that: 1 at both Tas, LH inhibition promoted a peculiar and sustained bout of NREM sleep characterized by an enhancement of slow-wave activity with no NREM-to-REM sleep transitions; 2 LH inhibition caused a marked transitory decrease in brain temperature at Ta 10°C, but not at Ta 24°C, suggesting that sleep changes induced by LH inhibition at thermoneutrality are not caused by a thermoregulatory impairment. These changes are far different from those observed after the short-term selective inhibition of either orexin or MCH neurons, suggesting that other LH neurons are involved in sleep-wake modulation.

  17. LH and ICRH RF electric field measurements using Doppler-free Saturation Spectroscopy

    Science.gov (United States)

    Martin, E. H.; Zafar, A.; Caughman, J. B. O.; Isler, R. C.; Bell, G. L.

    2016-10-01

    The physics mechanisms of wave heating and current drive processes in the bulk hot plasma are generally well identified, however, details of the wave-plasma interaction in the cold plasma edge are still not fully understood. To investigate the alluding physics non-perturbative diagnostics are required due to the large energy flux traversing the space associated with the corresponding RF antenna/launcher. A spectroscopic diagnostic, based on Doppler-free saturation spectroscopy, is currently under development at ORNL that will be capable of measuring RF electric fields with high precision (20 V/cm). The RF electric field is determined by systematically fitting a Balmer series spectral line profile obtained via DFSS using a previous validated non-perturbative quantum mechanically model. The spectral line profile is measured using Doppler-free saturation spectroscopy (DFSS). DFSS is a laser-based technique involving two counter-propagating beams, referred to as the pump and probe, which are made to overlap at a single point in space. The frequency of the laser is swept over that associated with the electronic transition of interest and the probe beam absorption intensity is measured. In this presentation an active spectroscopic technique allowing for measurements of the RF electric field driving wave-plasma interactions for lower hybrid (LH) and ion cyclotron resonance heating (ICRH) systems, based on DFSS, will be discussed. Initial measurements of the electric field in the magnetized capacitively coupled RF sheath obtained on a laboratory test stand will be presented.

  18. Transformer Industry Productivity Slows.

    Science.gov (United States)

    Otto, Phyllis Flohr

    1981-01-01

    Annual productivity increases averaged 2.4 percent during 1963-79, slowing since 1972 to 1.5 percent; computer-assisted design and product standardization aided growth in output per employee-hour. (Author)

  19. Intranasal LH-RH treatment of cryptorchidism. A clinical trial and 5 years follow-up

    DEFF Research Database (Denmark)

    Thorup, Jørgen Mogens; Mauritzen, K; Skakkebaek, N E

    1987-01-01

    The effect of intranasal LH-RH on cryptorchidism was investigated in 45 prepubertal boys with 68 undescended testes. A daily dose of 1.2 mg LH-RH was given for 4 weeks. A total of 16 testes (24%) descended. Follow-up examination 5 years later showed that relapse had occurred in two cases. Fifty-t...

  20. Nanoscale Confinement and Fluorescence Effects of Bacterial Light Harvesting Complex LH2 in Mesoporous Silicas

    DEFF Research Database (Denmark)

    Ikemoto, Hideki; Tubasum, Sumera; Pullerits, Tonu;

    2013-01-01

    harvesting complex LH2 in nanoscale chemical environments. Mesoporous silicas (SBA-15 family) with different shapes and pore sizes were synthesized and used to create nanoscale biomimetic environments for molecular confinement of LH2. A combination of UV-vis absorption, wide-field fluorescence microscopy...

  1. Role of exogenous estrogen in initiation of estrus and induction of an LH surge

    Science.gov (United States)

    Among cattle the LH surge that causes ovulation occurs shortly after the onset of a spontaneous estrus. In addition an injection of 100 'g of GnRH can induce an LH surge capable of inducing ovulation. We hypothesized that different preovulatory estradiol profiles would result in different ovulator...

  2. In vitro regulation of LH biosynthesis and release by GnRH and estradiol

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, J.W.

    1986-01-01

    Anterior pituitaries were taken from female rats at random stages of the estrous cycle, enzymatically dispersed, and cultured for 48h in steroid-free ..cap alpha..-modified Eagles medium followed by 24h in fresh medium +/- estradiol (E/sub 2/). The pituitary cells were then incubated in fresh medium containing radiolabeled precursors +/- gonadotropin releasing hormone (GnRH). Radioactive precursor incorporation into LH was determined by immuno-precipitation. The dose-dependent effects of E/sub 2/(10/sup -11/ to 10/sup -8/M) on /sup 3/H-glucosamine (/sup 3/H-Gln) and /sup 35/S-methionine (/sup 35/S-Met) incorporation into LH +/- 1 nM GnRH (4h) were investigated. GnRH (10/sup -9/M) and E/sub 2/ (all doses) significantly increased total /sup 3/H-Gln LH. Moreover, E/sub 2/ at 10/sup -9/M and 10/sup -8/M significantly enhanced GnRH stimulated LH glycosylation. In contrast, addition of GnRH and/or E/sub 2/ did not significantly increase /sup 35/S-Met incorporation into LH over a 4h period. The effects of various GnRH concentrations (10/sup -11/ to 10/sup -9/M; 8h) +/- E/sub 2/ (0.05 nM) on /sup 3/H-Gln LH and /sup 35/S-Met LH production were also investigated. In the absence of E/sub 2/, only 10/sup -9/M GnRH was effective in increasing total /sup 3/H-Gln LH and /sup 35/S-Met LH synthesis. However, in the presence of E/sub 2/, all concentrations of GnRH stimulated LH synthesis with /sup 3/H-Gln LH production responding in a dose related manner whereas /sup 35/S-Met LH production was maximally stimulated at all doses of GnRH. In the final series of experiments, pituitary cells previously exposed to estradiol were incubated for 4 h in normal calcium or low calcium medium containing /sup 3/H-Gln or /sup 35/S-Met +/- GnRH. Removal of extracellular calcium completely inhibited GnRH stimulated /sup 3/H-Gln LH and /sup 35/S-Met LH production.

  3. Overview of L-H power threshold studies in NSTX

    Science.gov (United States)

    Maingi, R.; Kaye, S. M.; Bell, R. E.; Biewer, T. M.; Chang, C. S.; Gates, D. A.; Gerhardt, S. P.; Hosea, J.; LeBlanc, B. P.; Meyer, H.; Mueller, D.; Park, G.-Y.; Raman, R.; Sabbagh, S. A.; Stevenson, T. A.; Wilson, J. R.

    2010-06-01

    A summary of results from recent L-H power threshold (PLH) experiments in the National Spherical Torus Experiment is presented. First PLH (normalized linearly by plasma density) was found to be a minimum in double-null configuration, tending to increase as the plasma was shifted more strongly towards lower- or upper-single null configuration with either neutral beam or rf heating. The measured PLH/ne was comparable with neutral beam or rf heating, suggesting that rotation was not playing a dominant role in setting the value of PLH. The role of triangularity (δbot) in setting PLH/ne is less clear: while 50% less auxiliary heating power was required to access H-mode at low δbot than at high δbot, the high δbot discharges had lower ohmic heating and higher dW/dt, leading to comparable loss of power over a range of δbot. In addition, the dependences of PLH on the density, species (helium versus deuterium), plasma current, applied non-axisymmetric error fields and lithium wall conditioning are summarized.

  4. Full steady state LH scenarios in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian-Vibert, F.; Litaudon, X.; Arslanbekov, R.; Hoang, G.T.; Moreau, D.; Peysson, Y. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee

    1995-12-31

    Lower Hybrid discharge have been realised in Tore Supra using feed-back control of the primary circuit voltage such that the loop voltage was maintained exactly to zero near the plasma surface. This new scenario allows the plasma current to float and quickly reach an equilibrium value determined by the current drive efficiency and Lower Hybrid power. Recent experimental results show that, with the new constant flux scenario the coupled plasma and primary currents reach a steady state in less than 10 s which is a good agreement with theoretical expectations. A complete analysis of this scenario is presented. (authors). 8 refs., 3 figs.

  5. Slow light beam splitter.

    Science.gov (United States)

    Xiao, Yanhong; Klein, Mason; Hohensee, Michael; Jiang, Liang; Phillips, David F; Lukin, Mikhail D; Walsworth, Ronald L

    2008-07-25

    We demonstrate a slow light beam splitter using rapid coherence transport in a wall-coated atomic vapor cell. We show that particles undergoing random and undirected classical motion can mediate coherent interactions between two or more optical modes. Coherence, written into atoms via electromagnetically induced transparency using an input optical signal at one transverse position, spreads out via ballistic atomic motion, is preserved by an antirelaxation wall coating, and is then retrieved in outgoing slow light signals in both the input channel and a spatially-separated second channel. The splitting ratio between the two output channels can be tuned by adjusting the laser power. The slow light beam splitter may improve quantum repeater performance and be useful as an all-optical dynamically reconfigurable router.

  6. Lower Hybrid antennas for nuclear fusion experiments

    CERN Document Server

    Hillairet, Julien; Bae, Young-Soon; Bai, X; Balorin, C; Baranov, Y; Basiuk, V; Bécoulet, A; Belo, J; Berger-By, G; Brémond, S; Castaldo, C; Ceccuzzi, S; Cesario, R; Corbel, E; Courtois, X; Decker, J; Delmas, E; Delpech, L; Ding, X; Douai, D; Ekedahl, A; Goletto, C; Goniche, M; Guilhem, D; Hertout, P; Imbeaux, F; Litaudon, X; Magne, R; Mailloux, J; Mazon, D; Mirizzi, F; Mollard, P; Moreau, P; Oosako, T; Petrzilka, V; Peysson, Y; Poli, S; Preynas, M; Prou, M; Saint-Laurent, F; Samaille, F; Saoutic, B

    2015-01-01

    The nuclear fusion research goal is to demonstrate the feasibility of fusion power for peaceful purposes. In order to achieve the conditions similar to those expected in an electricity-generating fusion power plant, plasmas with a temperature of several hundreds of millions of degrees must be generated and sustained for long periods. For this purpose, RF antennas delivering multi-megawatts of power to magnetized confined plasma are commonly used in experimental tokamaks. In the gigahertz range of frequencies, high power phased arrays known as "Lower Hybrid" (LH) antennas are used to extend the plasma duration. This paper reviews some of the technological aspects of the LH antennas used in the Tore Supra tokamak and presents the current design of a proposed 20 MW LH system for the international experiment ITER.

  7. Experimental characterization of the lower hybrid wave field on the first pass using a magnetic probe array

    Science.gov (United States)

    Shinya, T.; Baek, S. G.; Wallace, G. M.; Parker, R. R.; Shiraiwa, S.; Takase, Y.

    2016-10-01

    Experimental characterization of the lower hybrid (LH) wave propagation from the launcher to the core plasma is important to validate an antenna spectrum model and to identify parasitic wave-edge plasma interactions occurring in front of the launcher. On Alcator C-Mod, the wave frequency spectrum and dominant parallel wavenumber are characterized with two probe arrays installed near the edge plasma. The first one is mounted on a radially movable structure that is about 108 deg toroidally away from the launcher. A phasing scan experiment at moderate density suggests a resonance-cone propagation of the launched slow LH wave with a finite spectral width. As plasma density is raised, the measured power decreases, correlated with the observed loss of efficiency. Recently, the second probe array with an increased number of probes has been installed on a limiter that is 54 deg. toroidally away from the launcher, which is expected to be dominantly sensitive to the wave-field directly leaving the launcher. An initial measurement shows that the probe array detects a coherent wave field. A full-wave model to evaluate the wave electric-field pattern in front of the probe array is under development. If available, further experimental and modeling results will be presented. Supported by USDoE Award(s) DE-FC02-99ER54512 and Japan/U.S. Cooperation in Fusion Research and Development.

  8. The Activities of Lysyl Hydroxylase 3 (LH3) Regulate the Amount and Oligomerization Status of Adiponectin

    Science.gov (United States)

    Ruotsalainen, Heli; Wang, Yu; Karppinen, Marjo; Bergmann, Ulrich; Kvist, Ari-Pekka; Pospiech, Helmut; Herzig, Karl-Heinz; Myllylä, Raili

    2012-01-01

    Lysyl hydroxylase 3 (LH3) has lysyl hydroxylase, galactosyltransferase, and glucosyltransferase activities, which are sequentially required for the formation of glucosylgalactosyl hydroxylysines in collagens. Here we demonstrate for the first time that LH3 also modifies the lysine residues in the collagenous domain of adiponectin, which has important roles in glucose and lipid metabolism and inflammation. Hydroxylation and, especially, glycosylation of the lysine residues of adiponectin have been shown to be essential for the formation of the more active high molecular weight adiponectin oligomers and thus for its function. In cells that totally lack LH3 enzyme, the galactosylhydroxylysine residues of adiponectin were not glucosylated to glucosylgalactosylhydroxylysine residues and the formation of high and middle molecular weight adiponectin oligomers was impaired. Circulating adiponectin levels in mutant mice lacking the lysyl hydroxylase activity of LH3 were significantly reduced, which indicates that LH3 is required for complete modification of lysine residues in adiponectin and the loss of some of the glycosylated hydroxylysine residues severely affects the secretion of adiponectin. LH mutant mice with reduced adiponectin level showed a high fat diet-induced increase in glucose, triglyceride, and LDL-cholesterol levels, hallmarks of the metabolic syndrome in humans. Our results reveal the first indication that LH3 is an important regulator of adiponectin biosynthesis, secretion and activity and thus might be a potential candidate for therapeutic applications in diseases associated with obesity and insulin resistance. PMID:23209641

  9. The cytoskeleton proteins and LH-regulated steroidogenesis in porcine luteal cells

    Energy Technology Data Exchange (ETDEWEB)

    Gregoraszczuk, Ewa L.; Slomczynska, Maria [Uniwersytet Jagiellonski, Cracow (Poland)

    1996-12-31

    The involvement of microtubules (MT) and microflilaments (MF) in LH-regulation of luteal cell stereoidogenesis was assessed at the middle stage of corpus luteum development. The influence microtubule- and microfilament-altering agents on basal and LH-stimulated progesterone (P4) production and secretion into the incubation medium was determined by RIA. LH-stimulated P4 production was 2.5 times higher than in the control cultures. Cytochalasis B (Cyt B) was without effect on basal P4 synthesis but increased the basal fraction of P4 secreted into the incubation medium, while colchicine (Col) increased both basal P4 synthesis and the fraction of P4 secreted into the incubation medium. LH-stimulated progesterone synthesis was reduced by Col, but the fraction secreted into the incubation medium increased. Cyt B had no effect on LH-stimulated synthesis but it decreased the fraction of P4 secreted into the incubation medium. Our findings demonstrate significant differences in the effect of Cyt B and Col on steroidogenesis in corpus luteum. We conclude that microtubules play an important role in the process of LH-stimulated P4 synthesis, while microfilaments act in the process of basal and LH-stimulated P4 secretion. (author). 23 refs, 4 figs.

  10. Study of the bacterial diversity of foods: PCR-DGGE versus LH-PCR.

    Science.gov (United States)

    Garofalo, Cristiana; Bancalari, Elena; Milanović, Vesna; Cardinali, Federica; Osimani, Andrea; Sardaro, Maria Luisa Savo; Bottari, Benedetta; Bernini, Valentina; Aquilanti, Lucia; Clementi, Francesca; Neviani, Erasmo; Gatti, Monica

    2017-02-02

    The present study compared two culture-independent methods, polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and length-heterogeneity polymerase chain reaction (LH-PCR), for their ability to reveal food bacterial microbiota. Total microbial DNA and RNA were extracted directly from fourteen fermented and unfermented foods, and domain A of the variable regions V1 and V2 of the 16S rRNA gene was analyzed through LH-PCR and PCR-DGGE. Finally, the outline of these analyses was compared with bacterial viable counts obtained after bacterial growth on suitable selective media. For the majority of the samples, RNA-based PCR-DGGE revealed species that the DNA-based PCR-DGGE was not able to highlight. When analyzing either DNA or RNA, LH-PCR identified several lactic acid bacteria (LAB) and coagulase negative cocci (CCN) species that were not identified by PCR-DGGE. This phenomenon was particularly evident in food samples with viable loadsPCR was able to detect a higher number of peaks in the analyzed food matrices relative to species identified by PCR-DGGE. In light of these findings, it may be suggested that LH-PCR shows greater sensitivity than PCR-DGGE. However, PCR-DGGE detected some other species (LAB included) that were not detected by LH-PCR. Therefore, certain LH-PCR peaks not attributed to known species within the LH-PCR database could be solved by comparing them with species identified by PCR-DGGE. Overall, this study also showed that LH-PCR is a promising method for use in the food microbiology field, indicating the necessity to expand the LH-PCR database, which is based, up to now, mainly on LAB isolates from dairy products. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Slowing Kidney Disease

    Science.gov (United States)

    ... takes years of daily use for NSAIDs to cause CKD. But, once CKD is present, NSAIDs can make ... in the wrong places can “oxidize” and cause damage, a lot like rust. Antioxidants ... Fish oil can help slow CKD that is caused by a disease called IgA ...

  12. Full steady state LH scenarios in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian-Vilbert, F.; Litaudon, X.; Arslanbekov, R.; Hoang, G.T.; Moreau, D.; Peysson, Y. [Association EURATOM-CEA sur la fusion, Departement de Recherches sur la Fusion Controlee, Centre d`detudes de Cadarache, F-13108 Saint-Paul-Lez-Durance (France)

    1996-02-01

    Lower hybrid discharges have been realised in Tore Supra using feed-back control of the primary circuit voltage (V{sub oh}) such that the loop voltage was maintained exactly zero near the plasma surface. This new scenario allows the plasma current to float and quickly reach an equilibrium value determined by the current drive efficiency and Lower Hybrid power. Recent experimental results show that, with the new {open_quote}{open_quote}constant flux{close_quote}{close_quote} scenario the coupled plasma and primary currents reach a steady state in less than 10 s which is in good agreement with theoretical expectations. A complete analysis of this scenario is presented. {copyright} {ital 1996 American Institute of Physics.}

  13. RU486 administration blocks neuropeptide Y potentiation of luteinizing hormone (LH)-releasing hormone-induced LH surges in proestrous rats.

    Science.gov (United States)

    Bauer-Dantoin, A C; Tabesh, B; Norgle, J R; Levine, J E

    1993-12-01

    We previously demonstrated that NPY potentiates LHRH-induced LH secretion specifically under endocrine conditions in which preovulatory LH surges are generated. The present study was designed to test the hypothesis that NPY's facilitatory actions are dependent upon preovulatory progesterone secretion. In Exp 1, female rats were fitted with atrial catheters on diestrus. On proestrus, hourly blood samples were collected from 1100-2100 h. At 1230 h, rats received a sc injection of the progesterone receptor antagonist RU486 (6 mg/kg BW) or oil. At 1330 h, rats received pentobarbital (40 mg/kg BW), to block hypothalamic LHRH release, or saline. Every 30 min from 1400-1800 h, pentobarbital-treated rats received iv pulses of LHRH (15 ng/pulse) or saline along with concurrent pulses of NPY (5 micrograms/pulse), or saline. In Exp 2, rats received jugular catheters on diestrus, but were sampled every hour throughout the morning (0700-1600 h), rather than the afternoon, of proestrus. In these morning groups, pentobarbital was injected at 0830 h, and peptides (LHRH or combined LHRH and NPY solutions) were administered as pulses at 30-min intervals between 0900-1300 h. Results from Exp 1 were as follows: administration of RU486 to rats given an ip injection of vehicle at 1330 h and pulses of saline from 1400-1800 h completely blocked the endogenous LH surge. In oil-treated pentobarbital-blocked rats, concurrent administration of NPY with LHRH significantly (P < 0.01) potentiated the ability of LHRH to restore LH surges. However, NPY was without any potentiating effects in animals pretreated with RU486 at 1230 h. RU486 also attenuated the ability of LHRH alone to restore LH surges in pentobarbital-blocked rats. In Exp 2, NPY was without effect on LHRH-induced LH secretion during the morning hours of proestrus. Our results demonstrate that 1) NPY facilitates LHRH-induced LH surges on the afternoon of proestrus; 2) presumptive progesterone receptor blockade by RU486 completely

  14. Changes in the 5-HT2A receptor system in the pre-mammillary hypothalamus of the ewe are related to regulation of LH pulsatile secretion by an endogenous circannual rhythm

    Directory of Open Access Journals (Sweden)

    Karsch Fred J

    2003-01-01

    Full Text Available Abstract Background We wanted to determine if changes in the expression of serotonin 2A receptor (5HT2A receptor gene in the premammillary hypothalamus are associated with changes in reproductive neuroendocrine status. Thus, we compared 2 groups of ovariectomized-estradiol-treated ewes that expressed high vs low LH pulsatility in two different paradigms (2 groups per paradigm: (a refractoriness (low LH secretion or not (high LH secretion to short days in pineal-intact Ile-de-France ewes (RSD and (b endogenous circannual rhythm (ECR in free-running pinealectomized Suffolk ewes in the active or inactive stage of their reproductive rhythm. Results In RSD ewes, density of 5HT2A receptor mRNA (by in situ hybridization was significantly higher in the high LH group (25.3 ± 1.4 vs 21.4 ± 1.5 grains/neuron, P 3H-Ketanserin binding (a specific radioligand of the median part of the premammillary hypothalamus tended to be higher in the high group (29.1 ± 4.0 vs 24.6 ± 4.2 fmol/mg tissu-equivalent; P A receptor mRNA and 3H-Ketanserin binding were both significantly higher in the high LH group (20.8 ± 1.6 vs 17.0 ± 1.5 grains/neuron, P Conclusions We conclude that these higher 5HT2A receptor gene expression and binding activity of 5HT2A receptor in the premammillary hypothalamus are associated with stimulation of LH pulsatility expressed before the development of refractoriness to short days and prior to the decline of reproductive neuroendocrine activity during expression of the endogenous circannual rhythm.

  15. Crystal structure of the RC-LH1 core complex from Rhodopseudomonas palustris.

    Science.gov (United States)

    Roszak, Aleksander W; Howard, Tina D; Southall, June; Gardiner, Alastair T; Law, Christopher J; Isaacs, Neil W; Cogdell, Richard J

    2003-12-12

    The crystal structure at 4.8 angstrom resolution of the reaction center-light harvesting 1 (RC-LH1) core complex from Rhodopseudomonas palustris shows the reaction center surrounded by an oval LH1 complex that consists of 15 pairs of transmembrane helical alpha- and beta-apoproteins and their coordinated bacteriochlorophylls. Complete closure of the RC by the LH1 is prevented by a single transmembrane helix, out of register with the array of inner LH1 alpha-apoproteins. This break, located next to the binding site in the reaction center for the secondary electron acceptor ubiquinone (UQB), may provide a portal through which UQB can transfer electrons to cytochrome b/c1.

  16. Regulation of endometrial cancer cell growth by luteinizing hormone (LH) and follicle stimulating hormone (FSH)

    OpenAIRE

    Davies, S.; Bax, C M R; Chatzaki, E; Chard, Tim; Iles, Ray K.

    2000-01-01

    Gonadotrophin releasing hormone analogues (GnRHa) have been used to treat recurrent endometrial cancer. However, the mode of action is uncertain. Our previous studies showed no direct effect of GnRHa on endometrial cancer cell growth in vitro. We have now examined the effect of luteinizing hormone (LH) and follicle stimulating hormone (FSH) on endometrial cancer cell growth. The aim was to determine whether suppression of pituitary LH and FSH by GnRHa could explain the tumour regression seen ...

  17. Effects of recombinant LH treatment on folliculogenesis and responsiveness to FSH stimulation

    DEFF Research Database (Denmark)

    Durnerin, Cedrin I; Erb, K; Fleming, R

    2008-01-01

    BACKGROUND: The role of LH in sensitizing antral follicles to FSH is unclear. LH is required for normal hormone production and normal oocyte and embryo development, but follicular responses to LH may depend upon the stage of development. Potential roles at the early follicular phase were explored...... in a clinical setting by employing a sequential approach to stimulation by recombinant human (r-h) LH followed by r-hFSH in women who were profoundly down-regulated by depo GnRH agonist. METHODS: We employed a multi-centre, prospective, randomized approach. Women (n = 146) were treated in a long course high......-dose GnRH agonist (Decapeptyl, 4.2 mg s.c.) protocol and were randomized to receive r-hLH (Luveris, 300 IU/day) for a fixed 7 days, or no r-hLH treatment. This was followed by a standard r-hFSH stimulation regime (Gonal-F, 150 IU/day). Ultrasound and hormone assessments of responses were measured...

  18. Methodologic basis for the radioimmunoassay of endogenous LH-like activity in human prostatic tissue

    Energy Technology Data Exchange (ETDEWEB)

    Dorobek, W.; Misiorowski, W.; Niewiadomska, A.; Baranowska, B.; Zgliczynski, S.; Kuzaka, B.; Krzeski, T.

    1983-12-01

    The aim of this study was to develop a technique for the radioimmunological determination of the activity of LH-like substances in the human prostate. The material comprised 19 specimens of prostatic tissue obtained during transbladder extirpation in patients with benign prostatic hyperplasia. Tissues of human testes and human skeletal muscle were used as controls. The method adopted for LH extraction from the membrane fraction of human prostatic tissue appeared to be sufficiently specific, accurate and sensitive for routine laboratory investigations. The concentrations of the LH-like immunoreactivity in human testicular tissue was found to be 57, 46 and 70 mU per g of the membrane fraction while those of the prostatic gland tissues ranged from 34 to 155 mU per g of the membrane fraction. However such LH-like substance was not found in human skeletal muscle tissue. It seems that the LH-type activity is an indirect proof for the existence of LH receptors in the human prostate.

  19. Leaf Downward Curvature and Delayed Flowering Caused by AtLH Overexpression in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    WUHao; YULin; TANGXiang-Rong; SHENRui-Juan; HEYu-Ke

    2004-01-01

    AtLHgene of Arabidopsis is a BcpLH(leafy head) homolog of Chinese cabbage, which encodes a double-stranded RNA-binding protein related to the curvature of folding leaf leading to the formation of leafy head. In order to elucidate the regulatory function of AtLH in the development of leaf curvature, we made a construct of 35S::AtLHand transformed it to Arabidopsis. In transgenic plants for sense-AtLH, transcripts of AtLH gene were increased significantly in leaves and flowers, giving rise to the AtLH-overexpressed plants in which the rosette leaves curved downward or outward in a manner of enhanced epinastic growth. Compared with normal plants, bolting and flowering time of the transgenic plants was significantly delayed. Moreover, the apical dominance of transgenic plants was weaker in vegetative shoots since more axillary shoots emerged from axil of rosette leaves, while stronger in flowering shoots because fewer cauline inflorescences were observed on the main inflorescence. In other aspects, these transgenic plants exhibited an increase in root-stimulating response to IAA and decrease in root-inhibitory reaction on ABA. It indicates that overexpression of AtLH causes downward curvature of transgenic plants.

  20. Mutation Analysis of the LH Receptor Gene in Leydig Cell Adenoma and Hyperplasia and Functional and Biochemical Studies of Activating Mutations of the LH Receptor Gene

    NARCIS (Netherlands)

    Boot, Annemieke M.; Lumbroso, Serge; Verhoef-Post, Miriam; Richter-Unruh, Annette; Looijenga, Leendert H. J.; Funaro, Ada; Beishuizen, Auke; van Marle, Andre; Drop, Stenvert L. S.; Themmen, Axel P. N.

    2011-01-01

    Context: Germline and somatic activating mutations in the LH receptor (LHR) gene have been reported. Objective: Our objective was to perform mutation analysis of the LHR gene of patients with Leydig cell adenoma or hyperplasia. Functional studies were conducted to compare the D578H-LHR mutant with t

  1. Differences in signal activation by LH and hCG are mediated by the LH/CG receptor`s extracellular hinge region

    Directory of Open Access Journals (Sweden)

    Paul eGrzesik

    2015-09-01

    Full Text Available The human lutropin/choriogonadotropin receptor (LHCGR can be activated by binding two slightly different gonadotropic glycoprotein hormones, choriogonadotropin (CG - secreted by the placenta, and lutropin (LH - produced by the pituitary. They induce different signaling profiles at the LHCGR. This cannot be explained by binding to the receptor's leucine-rich repeat domain (LRRD, as this binding is similar for the two hormones. We therefore speculate that there are previously unknown differences in the hormone/receptor interaction at the extracellular hinge region, which might help to understand functional differences between the two hormones. We have therefore performed a detailed study of the binding and action of LH and CG at the LHCGR hinge region. We focused on a primate-specific additional exon in the hinge region, which is located between LRRD and the serpentine domain. The segment of the hinge region encoded by exon10 was previously reported to be only relevant to hLH signaling, as the exon10-deletion receptor exhibits decreased hLH signaling, but unchanged hCG signaling. We designed an advanced homology model of the hormone/LHCGR complex, followed by experimental characterization of relevant fragments in the hinge region. In addition, we examined predictions of a helical exon10-encoded conformation by block-wise polyalanine (helix supporting mutations. These helix preserving modifications showed no effect on hormone induced signaling. However, introduction of a structure-disturbing double-proline mutant LHCGR-Q303P/E305P within the exon10-helix has, in contrast to exon10 deletion, no impact on hLH, but only on hCG signaling. This opposite effect on signaling by hLH and hCG can be explained by distinct sites of hormone interaction in the hinge region s. In conclusion, our analysis provides details of the differences between hLH- and hCG-induced signaling that are mainly determined in the L2-beta loop of the hormones and in the hinge region

  2. Magnetic ripple and the modeling of lower-hybrid current drive in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Peysson, Y.; Arslanbekov, R.; Basiuk, V.; Carrasco, J.; Litaudon, X.; Moreau, D. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Bizarro, J.P. [Instituto Superior Tecnico, Lisbon (Portugal). Lab. de Quimica Organica

    1996-01-01

    Using ray-tracing, a detailed investigation of the lower hybrid (LH) wave propagation in presence of toroidal magnetic field ripple is presented. By coupling ray tracing with a one-dimensional relativistic Fokker-Planck code, simulations of LH experiments have been performed for the Tore Supra tokamak. Taking into account magnetic ripple in LH simulations, a better agreement is found between numerical predictions and experimental observations, such as non-thermal Bremsstrahlung emission, current profile, ripple-induced power losses in local magnetic mirrors, when plasma conditions correspond to the ` `few passes` regime. (author). 47 refs.

  3. Particle-in-cell simulation study of a lower-hybrid shock

    Science.gov (United States)

    Dieckmann, M. E.; Sarri, G.; Doria, D.; Ynnerman, A.; Borghesi, M.

    2016-06-01

    The expansion of a magnetized high-pressure plasma into a low-pressure ambient medium is examined with particle-in-cell simulations. The magnetic field points perpendicular to the plasma's expansion direction and binary collisions between particles are absent. The expanding plasma steepens into a quasi-electrostatic shock that is sustained by the lower-hybrid (LH) wave. The ambipolar electric field points in the expansion direction and it induces together with the background magnetic field a fast E cross B drift of electrons. The drifting electrons modify the background magnetic field, resulting in its pile-up by the LH shock. The magnetic pressure gradient force accelerates the ambient ions ahead of the LH shock, reducing the relative velocity between the ambient plasma and the LH shock to about the phase speed of the shocked LH wave, transforming the LH shock into a nonlinear LH wave. The oscillations of the electrostatic potential have a larger amplitude and wavelength in the magnetized plasma than in an unmagnetized one with otherwise identical conditions. The energy loss to the drifting electrons leads to a noticeable slowdown of the LH shock compared to that in an unmagnetized plasma.

  4. Effect of monensin on the estrogen-induced LH surge in prepuberal heifers.

    Science.gov (United States)

    Randel, R D; Rutter, L M; Rhodes, R D

    1982-04-01

    The effect of dietary monensin on the luteinizing hormone (LH) surge following estradiol-17 beta (E2) injection was investigated in prepuberal Simmental X Brahman-Hereford heifers. Ten heifers, weighing approximately 260 kg and approximately 10 mo of age, were equally divided by age and weight into two groups: control (C) heifers each received 1.8 kg/d of a concentrate diet plus Coastal bermudagrass hay ad libitum; monensin (M) heifers each received the same diet plus 200 mg monensin/d. All heifers were maintained in dry lots on their respective diets for 14 d before the E2 challenge. On d 15, all heifers were injected in with 5 mg of E2 in corn oil. Blood samples were collected via tail vessel puncture immediately before E2 injection and at 2-h intervals until 48 h after the E2 injection. The samples were processed for serum and stored at -20 degrees C until LH concentrations were measured by radioimmunoassay. Mean concentrations of LH in serum differed (P less than .005) between C and M heifers and with time after E2 injection. A treatment X sampling period interaction (P less than .10) indicated that maximum serum concentrations of LH (LH surge) were detected earlier (P less than .001) for M (17.2 +/- 1.8 h) than C (27.0 +/- 6.0 h) heifers after the E2 injection. When the data were arrayed relative to the time of the LH surge, treatment (P less than .05) and sampling period (P less than .001) effects were significant, but a treatment X sampling period interaction was not detected. Peak LH concentration was 23.1 +/- 3.0 ng/ml for M heifers and 21.6+/- 4.2 ng/ml for controls (P greater than .10). Duration of the LH surge was 8.0 +/- .9 h in M heifers and 4.8 +/- 1.6 h in C heifers (P less than .001). Area under the LH surge was greater (P less than .001) in M heifers than in control heifers. We conclude that dietary monensin altered the estrogen-induced LH surge in prepuberal heifers.

  5. Slowed Exports Growth

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The first half of 2010 is showing that the impacts of the financial crisis are still lingering.Zhao Jinping,a researcher at the Development Research Center of the State Council,says that the possible implementation of exit strategies in developed countries may deal a heavy blow to a global rally,and it will certainly result in slowed exports growth for China.Zhao published his opinion in the China Economic Times.The first part was published in issue No.33.Edited excerpts of the second part follow:

  6. A novel role for Lh3 dependent ECM modifications during neural crest cell migration in zebrafish.

    Directory of Open Access Journals (Sweden)

    Santanu Banerjee

    Full Text Available During vertebrate development, trunk neural crest cells delaminate along the entire length of the dorsal neural tube and initially migrate as a non-segmented sheet. As they enter the somites, neural crest cells rearrange into spatially restricted segmental streams. Extracellular matrix components are likely to play critical roles in this transition from a sheet-like to a stream-like mode of migration, yet the extracellular matrix components and their modifying enzymes critical for this transition are largely unknown. Here, we identified the glycosyltransferase Lh3, known to modify extracellular matrix components, and its presumptive substrate Collagen18A1, to provide extrinsic signals critical for neural crest cells to transition from a sheet-like migration behavior to migrating as a segmental stream. Using live cell imaging we show that in lh3 null mutants, neural crest cells fail to transition from a sheet to a stream, and that they consequently enter the somites as multiple streams, or stall shortly after entering the somites. Moreover, we demonstrate that transgenic expression of lh3 in a small subset of somitic cells adjacent to where neural crest cells switch from sheet to stream migration restores segmental neural crest cell migration. Finally, we show that knockdown of the presumptive Lh3 substrate Collagen18A1 recapitulates the neural crest cell migration defects observed in lh3 mutants, consistent with the notion that Lh3 exerts its effect on neural crest cell migration by regulating post-translational modifications of Collagen18A1. Together these data suggest that Lh3-Collagen18A1 dependent ECM modifications regulate the transition of trunk neural crest cells from a non-segmental sheet like migration mode to a segmental stream migration mode.

  7. A novel role for Lh3 dependent ECM modifications during neural crest cell migration in zebrafish.

    Science.gov (United States)

    Banerjee, Santanu; Isaacman-Beck, Jesse; Schneider, Valerie A; Granato, Michael

    2013-01-01

    During vertebrate development, trunk neural crest cells delaminate along the entire length of the dorsal neural tube and initially migrate as a non-segmented sheet. As they enter the somites, neural crest cells rearrange into spatially restricted segmental streams. Extracellular matrix components are likely to play critical roles in this transition from a sheet-like to a stream-like mode of migration, yet the extracellular matrix components and their modifying enzymes critical for this transition are largely unknown. Here, we identified the glycosyltransferase Lh3, known to modify extracellular matrix components, and its presumptive substrate Collagen18A1, to provide extrinsic signals critical for neural crest cells to transition from a sheet-like migration behavior to migrating as a segmental stream. Using live cell imaging we show that in lh3 null mutants, neural crest cells fail to transition from a sheet to a stream, and that they consequently enter the somites as multiple streams, or stall shortly after entering the somites. Moreover, we demonstrate that transgenic expression of lh3 in a small subset of somitic cells adjacent to where neural crest cells switch from sheet to stream migration restores segmental neural crest cell migration. Finally, we show that knockdown of the presumptive Lh3 substrate Collagen18A1 recapitulates the neural crest cell migration defects observed in lh3 mutants, consistent with the notion that Lh3 exerts its effect on neural crest cell migration by regulating post-translational modifications of Collagen18A1. Together these data suggest that Lh3-Collagen18A1 dependent ECM modifications regulate the transition of trunk neural crest cells from a non-segmental sheet like migration mode to a segmental stream migration mode.

  8. Spontaneous and electrochemically stimulated changes in plasma LH in the female rat following hypothalamic deafferentation.

    Science.gov (United States)

    Phelps, C P; Krieg, R J; Sawyer, C H

    1976-01-16

    Plasma LH levels in adult female rats were studied by radioimmunoassay 6 weeks after making frontal cuts (FC) at the optic chiasm with Halász knives of various sizes. Cuts made with a small knife (radius 1.3 mm) permitted a spontaneous rise in plasma LH during proestrus from a mean of 96 +/- 25 ng/ml at 14:00 h to 545 +/- 207 ng/ml at 18:00 h in 13 rats. Seven of the latter, with a mean plasma LH of 967 +/- 281 ng/ml at 18:00 h exhibited tubal ova at hemicastration (hemi-ovx) the following morning. In a similar experiment 6 FC females lesioned with a 1.5 mm knife had plasma LH levels of 53 +/- 7 ng/ml at 14:00 h, but showed neither detectable changes at 2 h intervals through 20:00 h nor ovulation at hemi-ovx. Similar results were obtained in 13 rats deafferented with a 2.0 mm knife. Nine weeks after FC and 3 weeks following hemi-ovx all animals were given pentobarbital (32 mg/kg i.p.) at 13:30 h and stimulated bilaterally in the medial preoptic area (MPO) passing 20 muA anodal DC X 60 sec through concentric bipolar steel electrodes placed 0.8 mm from the midline. All 3 groups of FC animals showed increases in plasma LH to comparable levels (range: 197 +/- 45-357 +/- 156 ng/ml) 1 h after stimulation. Electrochemical stimulation sites extended lateral to the cut locations on at least one side in all animals. The results of these studies suggest that chronically (9 week) deafferented female rats have the capacity to release pituitary LH in response to MPO electrochemical stimulation in spite of retrochiasmatic deafferentation, but that the ovaries of the persistent estrus rat are unresponsive to these amounts of circulating LH.

  9. Fsh and Lh direct conserved and specific pathways during flatfish semicystic spermatogenesis.

    Science.gov (United States)

    Chauvigné, François; Zapater, Cinta; Crespo, Diego; Planas, Josep V; Cerdà, Joan

    2014-10-01

    The current view of the control of spermatogenesis by Fsh and Lh in non-mammalian vertebrates is largely based on studies carried out in teleosts with cystic and cyclic spermatogenesis. Much less is known concerning the specific actions of gonadotropins during semicystic germ cell development, a type of spermatogenesis in which germ cells are released into the tubular lumen where they transform into spermatozoa. In this study, using homologous gonadotropins and a candidate gene approach, for which the genes' testicular cell-type-specific expression was established, we investigated the regulatory effects of Fsh and Lh on gene expression during spermatogenesis in Senegalese sole (Solea senegalensis), a flatfish with asynchronous and semicystic germ cell development. During early spermatogenesis, Fsh and Lh upregulated steroidogenesis-related genes and nuclear steroid receptors, expressed in both somatic and germ cells, through steroid-dependent pathways, although Lh preferentially stimulated the expression of downstream genes involved in androgen and progestin syntheses. In addition, Lh specifically promoted the expression of spermatid-specific genes encoding spermatozoan flagellar proteins through direct interaction with the Lh receptor in these cells. Interestingly, at this spermatogenic stage, Fsh primarily regulated genes encoding Sertoli cell growth factors with potentially antagonistic effects on germ cell proliferation and differentiation through steroid mediation. During late spermatogenesis, fewer genes were regulated by Fsh or Lh, which was associated with a translational and posttranslational downregulation of the Fsh receptor in different testicular compartments. These results reveal that conserved and specialized gonadotropic pathways regulate semicystic spermatogenesis in flatfish, which may spatially adjust cell germ development to maintain a continuous reservoir of spermatids in the testis.

  10. Slow Light Semiconductor Laser

    Science.gov (United States)

    2015-02-02

    we demonstrate a semiconductor laser with a spectral linewidth of 18 kHz in the telecom band around 1:55um. The views, opinions and/or findings...we demonstrate a semiconductor laser with a spectral linewidth of 18 kHz in the telecom band around 1:55um. Further, the large intracavity field...hybrid Si/III- V platforms Abstract The semiconductor laser is the principal light source powering the world-wide optical fiber network . Ever

  11. Single-molecule spectroscopy on RC-LH1 complexes of Rhodopseudomonas acidophila strain 10050.

    Science.gov (United States)

    Böhm, Paul S; Southall, June; Cogdell, Richard J; Köhler, Jürgen

    2013-03-21

    We have revisited the RC-LH1 complex from Rhodopseudomonas (Rps.) acidophila for single-molecule spectroscopy. For the current study the pigment-protein complexes were stabilized in the detergent buffer solution using a relatively mild detergent (dodecyl-β-D-maltoside (DDM) instead of lauryldimethylamine N-oxide (LDAO)). This leads to a significant reduction of the fraction of broken/dissociated RC-LH1 complexes with respect to previous studies and has allowed us to investigate a sufficiently large sample of individual RC-LH1 complexes. For most of the complexes the fluorescence-excitation spectra exhibit a narrow spectral feature at the red end of the spectrum. Analysis of the statistics of the spectral properties yields a close resemblance with the results obtained on RC-LH1 complexes from Rps. palustris for which a low-resolution X-ray structure is available. Based on this comparison we come to the conclusion that for both species the RC-LH1 complex can be described by the same structural model, that is, an overall elliptical assembly of pigments that features a gap.

  12. Physics of GAM-initiated L-H transition in a tokamak

    Science.gov (United States)

    Askinazi, L. G.; Belokurov, A. A.; Bulanin, V. V.; Gurchenko, A. D.; Gusakov, E. Z.; Kiviniemi, T. P.; Lebedev, S. V.; Kornev, V. A.; Korpilo, T.; Krikunov, S. V.; Leerink, S.; Machielsen, M.; Niskala, P.; Petrov, A. V.; Tukachinsky, A. S.; Yashin, A. Yu; Zhubr, N. A.

    2017-01-01

    Based on experimental observations using the TUMAN-3M and FT-2 tokamaks, and the results of gyrokinetic modeling of the interplay between turbulence and the geodesic acoustic mode (GAM) in these installations, a simple model is proposed for the analysis of the conditions required for L-H transition triggering by a burst of radial electric field oscillations in a tokamak. In the framework of this model, one-dimensional density evolution is considered to be governed by an anomalous diffusion coefficient dependent on radial electric field shear. The radial electric field is taken as the sum of the oscillating term and the quasi-stationary one determined by density and ion temperature gradients through a neoclassical formula. If the oscillating field parameters (amplitude, frequency, etc) are properly adjusted, a transport barrier forms at the plasma periphery and sustains after the oscillations are switched off, manifesting a transition into the high confinement mode with a strong inhomogeneous radial electric field and suppressed transport at the plasma edge. The electric field oscillation parameters required for L-H transition triggering are compared with the GAM parameters observed at the TUMAN-3M (in the discharges with ohmic L-H transition) and FT-2 tokamaks (where no clear L-H transition was observed). It is concluded based on this comparison that the GAM may act as a trigger for the L-H transition, provided that certain conditions for GAM oscillation and tokamak discharge are met.

  13. Slow change deafness.

    Science.gov (United States)

    Neuhoff, John G; Wayand, Joseph; Ndiaye, Mamoudou C; Berkow, Ann B; Bertacchi, Breanna R; Benton, Catherine A

    2015-05-01

    In four experiments, we demonstrated a new phenomenon called "slow-change deafness." In Experiment 1 we presented listeners with continuous speech that changed three semitones in pitch over time, and we found that nearly 50 % failed to notice the change. Experiments 2 and 3 replicated the finding, demonstrated that the changes in the stimuli were well above threshold, and showed that when listeners were alerted to the possibility of a change, detection rates improved dramatically. Experiment 4 showed that increasing the magnitude of the change that occurred in the stimulus decreased the rate of change deafness. Our results are consistent with previous work that had shown that cueing listeners to potential auditory changes can significantly reduce change deafness. These findings support an account of change deafness that is dependent on both the magnitude of a stimulus change and listener expectations.

  14. Slowed Exports Growth

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Ⅲ. Slowed export recovery in the second half Since the beginning of this year, global trade has maintained a recovery growth thanks to the worldwide economic rally.From January to April, the imports of three major Economics--the United States, the euro zone and Japan--rose 17.5 percent on average from a year ago. Import growths for the United States, the euro zone and Japan were 20.9 percent, 4.8 percent and 29 percent, respectively, which spurred China's exports to those regions. From January to June this year, China's exports totaled $705.09 billion, up 35.2 percent from the same period in 2009 and were 5.8 percent higher than the first half of 2008 when the crisis had yet to begin. Those figures indicated China's exports had rebounded to precrisis levels.

  15. Slow Scan Telemedicine

    Science.gov (United States)

    1984-01-01

    Originally developed under contract for NASA by Ball Bros. Research Corporation for acquiring visual information from lunar and planetary spacecraft, system uses standard closed circuit camera connected to a device called a scan converter, which slows the stream of images to match an audio circuit, such as a telephone line. Transmitted to its destination, the image is reconverted by another scan converter and displayed on a monitor. In addition to assist scans, technique allows transmission of x-rays, nuclear scans, ultrasonic imagery, thermograms, electrocardiograms or live views of patient. Also allows conferencing and consultation among medical centers, general practitioners, specialists and disease control centers. Commercialized by Colorado Video, Inc., major employment is in business and industry for teleconferencing, cable TV news, transmission of scientific/engineering data, security, information retrieval, insurance claim adjustment, instructional programs, and remote viewing of advertising layouts, real estate, construction sites or products.

  16. Preovulatory progesterone concentration associates significantly to follicle number and LH concentration but not to pregnancy rate

    DEFF Research Database (Denmark)

    Yding Andersen, Claus; Bungum, Leif; Nyboe Andersen, Anders

    2011-01-01

    Using data from a large prospective randomized controlled trial that evaluated the effect of recombinant LH (rLH)co-administration for ovarian stimulation, the present study assessed whether progesterone concentration on the day of human chorionic gonadotrophin (HCG) administration was associated...... with pregnancy outcome. Progesterone concentration was measured on stimulation day 1 and on the day of HCG administration in 475 patients who underwent IVF/intracytoplasmic sperm injection treatment following ovarian stimulation with gonadotrophin-releasing hormone (GnRH) agonist and recombinant FSH...... with or without rLH administration from day 6 of stimulation. There was no significant association between the late-follicular-phase progesterone concentration and the clinical pregnancy rate. However, progesterone concentration was strongly associated with the number of follicles and retrieved oocytes. Late...

  17. Veränderungen kognitiver Funktionen unter LH-RH-Therapie bzw. unter Bicalutamid-Monotherapie

    Directory of Open Access Journals (Sweden)

    Brössner C

    2009-01-01

    Full Text Available Einleitung: Androgendeprivationstherapie mit LH-RH-Agonisten bzw. Androgenrezeptorblockade mit Bicalutamid wurde zur Standardtherapie beim fortgeschrittenen Prostatakarzinom. Der Großteil der existierenden Literatur beschreibt unter LH-RH-Gabe und damit verbundener Senkung des Testosteronspiegels eine Verschlechterung bestimmter kognitiver Gedächtnisleistungen. Ziel unserer prospektiven, konsekutiven Studie ist es, kognitive und emotionale Funktionen sowie die Lebensqualität bei Männern unter LH-RH bzw. unter Bicalutamid-Monotherapie zu untersuchen. Methoden: In Gruppe A wurden 15 Männer (mean 70,5 a; 57–81 inkludiert, die ein LH-RHAnalogon für 1 Jahr erhielten. In Gruppe B wurden 12 Männer (mean 69,3 a; 56–80 unter Bicalutamid-Monotherapie (150 mg/d für 1 Jahr inkludiert. Zum Zeitpunkt der kognitiven Testung waren alle Patienten frei von klinischer Metastasierung und die PSA-Werte waren 0,5 ng/ml. Für die Untersuchung der kognitiven Leistungen wurde eine umfangreiche neuropsychologische alters-, geschlechts- und bildungskorrigierte Testbatterie eingesetzt: Tests für Aufmerksamkeit (ZVT, Stroop-Test, Gedächtnis (NAI, WMS-R, Demenz (MMSE, Lebensqualität (WHOQOL-BREF, Wahrnehmung (Mosaik-Test, Sprache (LPS 50 Depression (BDI sowie für Angst (STAI wurden durchgeführt. Ergebnisse: In Gruppe A (unter LH-RH fanden wir signifikante Defizite im topografischen (T = 39,3 und visuellen Langzeitgedächtnis (T = 35,6. Das visuelle und verbale Arbeitsgedächtnis zeigte in dieser Gruppe grenzwertige Defizite (T = 40,67 und T = 41,67. In Gruppe B (Bicalutamid konnten wir dagegen bei keinem der Patienten ein kognitives Defizit feststellen. Schlussfolgerung: Unsere Daten suggerieren einen signifikanten negativen Einfluss der LH-RHLangzeittherapie auf bestimmte kognitive Funktionen. Im Gegensatz dazu fanden wir keine Veränderungen unter Bicalutamid-Monotherapie.

  18. Preovulatory progesterone concentration associates significantly to follicle number and LH concentration but not to pregnancy rate

    DEFF Research Database (Denmark)

    Yding Andersen, Claus; Bungum, Leif; Nyboe Andersen, Anders

    2011-01-01

    Using data from a large prospective randomized controlled trial that evaluated the effect of recombinant LH (rLH)co-administration for ovarian stimulation, the present study assessed whether progesterone concentration on the day of human chorionic gonadotrophin (HCG) administration was associated...... with pregnancy outcome. Progesterone concentration was measured on stimulation day 1 and on the day of HCG administration in 475 patients who underwent IVF/intracytoplasmic sperm injection treatment following ovarian stimulation with gonadotrophin-releasing hormone (GnRH) agonist and recombinant FSH...

  19. Modification of ordinary-mode reflectometry system to detect lower-hybrid waves in Alcator C-Moda)

    Science.gov (United States)

    Baek, S. G.; Shiraiwa, S.; Parker, R. R.; Dominguez, A.; Kramer, G. J.; Marmar, E. S.

    2012-10-01

    Backscattering experiments to detect lower-hybrid (LH) waves have been performed in Alcator C-Mod, using the two modified channels (60 GHz and 75 GHz) of an ordinary-mode reflectometry system with newly developed spectral recorders that can continuously monitor spectral power at a target frequency. The change in the baseline of the spectral recorder during the LH wave injection is highly correlated to the strength of the X-mode non-thermal electron cyclotron emission. In high density plasmas where an anomalous drop in the lower hybrid current drive efficiency is observed, the observed backscattered signals are expected to be generated near the last closed flux surface, demonstrating the presence of LH waves within the plasma. This experimental technique can be useful in identifying spatially localized LH electric fields in the periphery of high-density plasmas.

  20. The effect of lower hybrid waves on JET plasma rotation

    Science.gov (United States)

    Nave, M. F. F.; Kirov, K.; Bernardo, J.; Brix, M.; Ferreira, J.; Giroud, C.; Hawkes, N.; Hellsten, T.; Jonsson, T.; Mailloux, J.; Ongena, J.; Parra, F.; Contributors, JET

    2017-03-01

    This paper reports on observations of rotation in JET plasmas with lower hybrid current drive. Lower hybrid (LH) has a clear impact on rotation. The changes in core rotation can be either in the co- or counter-current directions. Experimental features that could determine the direction of rotation were investigated. Changes from co- to counter-rotation as the q-profile evolves from above unity to below unity suggests that magnetic shear could be important. However, LH can drive either co- or counter-rotation in discharges with similar magnetic shear and at the same plasma current. It is not clear if a slightly lower density is significant. A power scan at fixed density, shows a lower hybrid power threshold around 3 MW. For smaller LH powers, counter rotation increases with power, while for larger powers a trend towards co-rotation is found. The estimated counter-torque from the LH waves, would not explain the observed angular frequencies, neither would it explain the observation of co-rotation.

  1. Slow frictional waves

    Science.gov (United States)

    Viswanathan, Koushik; Sundaram, Narayan; Chandrasekar, Srinivasan

    Stick-slip, manifest as intermittent tangential motion between two dry solid surfaces, is a friction instability that governs diverse phenomena from automobile brake squeals to earthquakes. We show, using high-speed in situ imaging of an adhesive polymer interface, that low velocity stick-slip is fundamentally of three kinds, corresponding to passage of three different surface waves -- separation pulses, slip pulses and the well-known Schallamach waves. These waves, traveling much slower than elastic waves, have clear distinguishing properties. Separation pulses and Schallamach waves involve local interface separation, and propagate in opposite directions while slip pulses are characterized by a sharp stress front and do not display any interface detachment. A change in the stick-slip mode from separation to slip pulse is effected simply by increasing the normal force. Together, these three waves constitute all possible stick-slip modes in adhesive friction and are shown to have direct analogues in muscular locomotory waves in soft bodied invertebrates. A theory for slow wave propagation is also presented which is capable of explaining the attendant interface displacements, velocities and stresses.

  2. Effects of Density and Slow Controlled Release Fertilizer on Growth Progress and Yield of HB Cotton Hybrid Lu 05 H9%密度和缓控释肥对红花标记杂交棉鲁05H9生育进程及产量的影响

    Institute of Scientific and Technical Information of China (English)

    姜辉; 赵军胜; 王家宝; 高明伟; 王秀丽; 陈莹; 王留明

    2014-01-01

    本试验以红花标记杂交棉鲁05 H9为材料,研究不同密度条件下缓控释肥对其生育进程及产量的影响。结果表明:鲁05 H9在不同处理条件下生育进程稳定,施缓控释肥四桃比例更为合理,伏桃和早秋桃所占比例较大;随着密度增大,总产量提高,群体铃数也增加,但单株铃数和平均铃重降低,密度对单株铃数的影响达到显著水平;与常规施肥相比,施缓控释肥可以提高平均铃重,同时影响产量及其构成因素;密度和施肥方式的交互作用对产量及其构成因素的影响未达到显著水平。在产量最高的4.2万株/hm2密度条件下,缓控释肥处理每公顷可以增收472元。因此,综合经济及环保效益,鲁05 H9在黄河流域棉区可以结合较高密度和缓控释肥方式加以推广应用。%With the HB hybrid Lu 05H9 as experiment material, the effects of slow controlled release fertilizer on growth progress and yield of cotton were studied under different densities .The results showed that the growth progress of Lu 05 H9 was stable under different treatment conditions .The treatment with slow con-trolled release fertilizer made the percentage of four kinds of boll more reasonable , and increased the percent-age of summer boll and early-autumn boll .The number of population bolls and total yield increased with the increase of density , but the number of bolls per individual plant and average single boll weight decreased . Plant density had the significant influences on the boll number per plant .Compared with the conventional fer-tilizer, the slow controlled release fertilizer could improve the average weight of single boll , but reduce the yield and its components .The interaction effect of density and fertilizer was insignificant on yield and its com-ponents .The economic benefit could increase by 472 yuan per hectare with slow controlled release fertilizer at the density of 42 thousand plants per

  3. Evaluation on performance of Beckman Coulter LH-750 hematocyte analyzer%Beckman Coulter LH-750血细胞分析仪性能评价

    Institute of Scientific and Technical Information of China (English)

    张伟; 木合布力·艾沙

    2011-01-01

    目的 系统评价LH-750全自动血细胞分析仪的性能.方法 选用定值质控全血连续重复测定,选取白细胞、红细胞、血小板计数、血小板压积和血红蛋白5个主要参数以评价仪器的精密度、准确度和不确定度;高、低值样品连续重复3次评价仪器的携带污染率;将全血按比例稀释并进行检测,作线性范围的评价;以两种不同的进样模式测定标本,计算偏倚率;同一份标本分别用LH-750和Sysmex1000i同时检测,观察两者之间的相关性.结果 质控物测定结果CV≤2.96%,携带污染率小于或等于0.56%,LH-750线性较好,与Sysmex1000i测定的结果比较,相关性良好(r≥0.996 6).结论 LH-750型血细胞分析仪的准确性、精密度均良好,携带污染率低且线性较好,与sysmex1000i具有良好的一致性,能满足血液分析的一般要求.%Objective To evaluate the performance of Beckman Coulter LH 750 automated hematology analyzer. Methods Rating quality control whole blood was successively and repetitively to evaluate the accuracy, precision and uncertainty which obey to the standard of ICSH and NCCLS; high and low value serum specimens were determined for successive 3 times to investigate the carry over rate. Dilute the blood by the same proportion to measure line range; Detect the samples with two different sampling modes and compared. Detect the sample with LH 750 and sysmexl000i hematology analyzer respectively and compared. Results The result of quality control specimen showed CV was below 2.96 % , and the carry over rate was below 0.6 %. The result correlated well with those obtained on Sysmexl000i(r>0. 996 ). Conclusion Beckman Coulter LH 750 hematocyte analyzer possess high precision and accuracy,low carry over rate, excellent line range,and closely correlative to sysmexl000i and achieves the clinical demand for hematological analysis.

  4. A Case for Slow Reading

    Directory of Open Access Journals (Sweden)

    Matthew J Ostercamp

    2014-05-01

    Full Text Available This essay makes a case for the value of slow or deep reading.  Inspired by the Slow Food movement it seeks to apply their principles to reading.  It begins by exploring the meaning of information and how like food, information has come to be regarded as a commodity.  Drawing upon the philosophy of Albert Borgmann, it counters the prevalent commodity view of information by offering an alternative paradigm that connects careful reading to human flourishing.  It argues that by connecting information to pleasure and community, slow reading advocates can have comparable success to that enjoyed by the slow food movement.

  5. Slow light and slow acoustic phonons in optophononic resonators

    Science.gov (United States)

    Villafañe, V.; Soubelet, P.; Bruchhausen, A. E.; Lanzillotti-Kimura, N. D.; Jusserand, B.; Lemaître, A.; Fainstein, A.

    2016-11-01

    Slow and confined light have been exploited in optoelectronics to enhance light-matter interactions. Here we describe the GaAs/AlAs semiconductor microcavity as a device that, depending on the excitation conditions, either confines or slows down both light and optically generated acoustic phonons. The localization of photons and phonons in the same place of space amplifies optomechanical processes. Picosecond laser pulses are used to study through time-resolved reflectivity experiments the coupling between photons and both confined and slow acoustic phonons when the laser is tuned either with the cavity (confined) optical mode or with the stop-band edge (slow) optical modes. A model that fully takes into account the modified propagation of the acoustic phonons and light in these resonant structures is used to describe the laser detuning dependence of the coherently generated phonon spectra and amplitude under these different modes of laser excitation. We observe that confined light couples only to confined mechanical vibrations, while slow light can generate both confined and slow coherent vibrations. A strong enhancement of the optomechanical coupling using confined photons and vibrations, and also with properly designed slow photon and phonon modes, is demonstrated. The prospects for the use of these optoelectronic devices in confined and slow optomechanics are addressed.

  6. Regulation of luteinizing hormone (LH) subunit biosynthesis in cultured male anterior pituitary cells: effects of GnRH and testosterone

    Energy Technology Data Exchange (ETDEWEB)

    Krummen, L.A.

    1988-01-01

    The purpose of this study was to evaluate the direct effects of testosterone (T) on LH subunit apoprotein synthesis, glycosylation and release by the male pituitary. Cells from 1 wk castrate rats were cultured for 48 h in steroid-free medium followed by 48h in media /+-/10nM T. The cells were then incubated for 2, 4, 6, 8, or 12h in media containing (/sup 35/S)-methionine (/sup 35/S-Met) or (/sup 3/H)-glucosamine (/sup 3/H-Gln), /+-/1nM GnRH (exp 1) or in media containing precursors /+-/ 10nM T and/or 1nM GnRH (exp 2). Radiolabeled precursor incorporation into LH subunits was determined by immunoprecipitation followed by SDS-PAGE. In experiment 1, precursor incorporation into total protein (TP) and LH subunits increased linearly with time for at least 8h. GnRH did not effect precursor incorporation in to TP or /sup 35/S-Met labeling of LH subunits, but stimulated a linear, time-dependent accumulation of /sup 3/H-Gln into total LH subunits and the release of RIA-LH and radiolabeled subunits into media. Based on these results, the effects of T on LH subunit biosynthesis were studied during an 8h incubation. In experiment 2, GnRH enhanced the total /sup 3/H-Gln incorporation (but not /sup 35/S-Met incorporation) into both LH subunits. GnRH stimulated the release of /sup 35/S-Met LH..cap alpha.. and /sup 3/H-Gln LH subunits into media and increased the relative glycosylation of secreted LH subunits without altering the relative glycosylation of intracellular LH subunits. T inhibited RIA-LH release and incorporation of both precursors into total and secreted LH subunits (/+-/GnRH). However, only the relative glycosylation of secreted LH..cap alpha.. was reduced by T (/+-/GnRh).

  7. LH-RH analogues in the treatment of young women with early breast cancer: long-term follow-up of a phase II study.

    Science.gov (United States)

    Recchia, Francesco; Necozione, Stefano; Bratta, Massimo; Rosselli, Michele; Guerriero, Gabriele; Rea, Silvio

    2015-03-01

    To prevent premature ovarian failure (POF), high-risk, premenopausal women with early breast cancer were given a luteinizing-hormone releasing hormone (LH-RH) analogue during adjuvant chemotherapy. After an adriamycin-based regimen, patients received radiation therapy concomitant with cyclophosphamide, methotrexate and 5-fluorouracil. An aromatase inhibitor was given to patients positive for the estrogen receptor (ER+). The median age was 43 years (range, 26-45). Among 200 consecutive patients, 46% had no axillary node, and 54% had a mean of 5.4 positive nodes (range, 1-25); 56% were ER+, 44% were estrogen receptor negative (ER-), 13% were triple negative, and 20 had tumors positive for the oncogene, c-erb-B2 (identified with fluorescent in situ hybridization). After a median follow-up of 105 months (range, 65-180), no patient under 40 years old exhibited POF, while 44% of patients over 40 years old exhibited POF. Eight pregnancies were recorded: 7 at term and 1 voluntary interruption. The 10-year disease-free survival and overall survival rates were 85 and 91%, respectively. These data showed that, in premenopausal patients with early breast cancer, the addition of an LH-RH analogue to adjuvant chemotherapy was well tolerated, prevented POF, and was associated with excellent disease-free survival and overall survival rates.

  8. Recent progress on lower hybrid current drive and implications for ITER

    CERN Document Server

    Hillairet, Julien; Goniche, M; Achard, J; Armitano, A; Beckett, B; Belo, J; Berger-By, G; Corbel, E; Delpech, L; Decker, J; Dumont, R; Guilhem, D; Kazarian, F; Litaudon, X; Magne, R; Marfisi, L; Mollard, P; Namkung, W; Nilsson, E; Park, S; Peysson, Y; Preynas, M; Sharma, P K; Prou, M

    2015-01-01

    The sustainment of steady-state plasmas in tokamaks requires efficient current drive systems. Lower Hybrid Current Drive (LHCD) is currently the most efficient method to generate a continuous additional off-axis toroidal plasma current as well as reduce the poloidal flux consumption during the plasma current ramp-up phase. The operation of the Tore Supra ITER-like LH launcher has demonstrated the capability to couple LH power at ITER-like power densities with very low reflected power during long pulses. In addition, the installation of eight 700kW/CW klystrons at the LH transmitter has allowed increasing the total LH power in long pulse scenarios. However, in order to achieve pure stationary LH sustained plasmas, some R\\&D are needed to increase the reliability of all the systems and codes, from the RF sources to the plasma scenario prediction. The CEA/IRFM is addressing some of these issues by leading a R\\&D program towards an ITER LH system and by the validation of an integrated LH modeling suite of...

  9. Particle-in-cell simulation study of a lower-hybrid shock

    CERN Document Server

    Dieckmann, Mark Eric; Doria, Domenico; Ynnerman, Anders; Borghesi, Marco

    2016-01-01

    The expansion of a magnetized high-pressure plasma into a low-pressure ambient medium is examined with particle-in-cell (PIC) simulations. The magnetic field points perpendicularly to the plasma's expansion direction and binary collisions between particles are absent. The expanding plasma steepens into a quasi-electrostatic shock that is sustained by the lower-hybrid (LH) wave. The ambipolar electric field points in the expansion direction and it induces together with the background magnetic field a fast E cross B drift of electrons. The drifting electrons modify the background magnetic field, resulting in its pile-up by the LH shock. The magnetic pressure gradient force accelerates the ambient ions ahead of the LH shock, reducing the relative velocity between the ambient plasma and the LH shock to about the phase speed of the shocked LH wave, transforming the LH shock into a nonlinear LH wave. The oscillations of the electrostatic potential have a larger amplitude and wavelength in the magnetized plasma than...

  10. Sequencing and generation of an infectious clone of the pathogenic goose parvovirus strain LH.

    Science.gov (United States)

    Wang, Jianye; Duan, Jinkun; Zhu, Liqian; Jiang, Zhiwei; Zhu, Guoqiang

    2015-03-01

    In this study, the complete genome of the virulent strain LH of goose parvovirus (GPV) was sequenced and cloned into the pBluescript II (SK) plasmid vector. Sequence alignments of the inverted terminal repeats (ITR) of GPV strains revealed a common 14-nt-pair deletion in the stem of the palindromic structure in the LH strain and three other strains isolated after 1982 when compared to three GPV strains isolated earlier than that time. Transfection of 11-day-old embryonated goose eggs with the plasmid pLH, which contains the entire genome of strain LH, resulted in successful rescue of the infectious virus. Death of embryos after transfection via the chorioallantoic membrane infiltration route occurred earlier than when transfection was done via the allantoic cavity inoculation route. The rescued virus exhibited virulence similar to that of its parental virus, as evaluated by the mortality rate in goslings. Generation of the pathogenic infectious clone provides us with a powerful tool to elucidate the molecular pathogenesis of GPV in the future.

  11. Possible applications of RIA of LH and FSH in diagnosis of Stein-Leventhal syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Zenisek, L.; Talas, M.; Stehlikova, J.; Fingerova, H.; Duskova, M.

    1981-01-01

    LH determination in the serum significantly assists in diagnosing polycystic ovaries. Values exceeding 22 mIU/ml serum are indicative of a typical picture of polycystic ovaries similar to those found in the Stein-Leventhal syndrome. Lower levels indicate an atypical picture of polycystic ovaries or low-cyst ovary degeneration. FSH level cannot be used for this diagnosis.

  12. Ovulation Prediction by using Urine LH Rapid Determination Combinedwith Cervical Mucus Score

    Institute of Scientific and Technical Information of China (English)

    吴宇芬; 狄文; 桂彪; 张惠英; 金忆; 肖宇红; 丁青; 王寒正; 孙志达; 沈维雄

    1993-01-01

    Infertility may be induced by many causes. It is partly due to the inappropriate time of intercourse from ignorance of the date of ovulation by the infertile couples.Basal body temperature, cervical mucus, B-ultrasonography, blood LH ( luteinizing hormone ) and sex-steroid hormone assay are the common methods used for monitoring ovulation.

  13. L-H transition in the mega-Amp spherical tokamak

    DEFF Research Database (Denmark)

    Akers, R.J.; Counsell, G.F.; Sykes, A.

    2002-01-01

    H-mode plasmas have been achieved on the MAST spherical tokamak at input power considerably higher than predicted by conventional threshold scalings. Following L-H transition, a clear improvement in energy confinement is obtained, exceeding recent international scalings even at densities approach...

  14. 2-bromopalmitate inhibition of stimulatory effect on LH in isolated luteal cells.

    Science.gov (United States)

    Tan, C H; Robinson, J

    1982-04-05

    The effect of 2-bromopalmitate, an inhibitor of fatty acids oxidation, on progesterone synthesis in isolated luteal cells was studied. Incubation of the cells with increasing concentrations (0 - 2 mM) of the inhibitor resulted in an initial enhancement of progesterone synthesis, both in the presence and absence of LH (1 microgram/ml). In the LH-treated cells, this stimulation in steroid synthesis becomes markedly impaired at 2 mM 2-bromopalmitate. In the control cells, however, progesterone synthesis was sustained at the elevated level. At high concentrations of 2-bromopalmitate, the stimulatory effect of LH (relative to the controls) on steroidogenesis was progressively diminished, until it was completely abolished at an inhibitor concentration of 2 mM. The oxidation of labelled palmitic acid by luteal cells was also effectively inhibited by 2-bromopalmitate (1 mM). The results indicate that the steroidogenic effect of LH is mediated, in part, by fatty acid oxidation, and were explained in terms of the interaction between carbohydrate and fatty acid oxidation in supporting ovarian steroidogenesis.

  15. A General Approach to L(h, k)-Label Interconnection Networks

    Institute of Scientific and Technical Information of China (English)

    Tiziana Calamoneri; Saverio Caminiti; Rossella Petreschi

    2008-01-01

    Given two non-negative integers h and k, an L(h, k)-labelin9 of a graph G = (V, E) is a function from the set V to a set of colors, such that adjacent nodes take colors at distance at least h, and nodes at distance 2 take colors at distanceat least k. The aim of the L(h, k)-labeling problem is to minimize the greatest used color. Since the decisional version of this problem is NP-complete, it is important to investigate particular classes of graphs for which the problem can be efficiently solved. It is well known that the most common interconnection topologies, such as Butterfly-like, Benes, CCC, Trivalent Cayley networks, are all characterized by a similar structure: they have nodes organized as a matrix and connections are divided into layers. So we naturally introduce a new class of graphs, called (l×n)-multistage graphs, containing the most common interconnection topologies, on which we study the L(h, k)-labeling. A general algorithm for L(h, k)-labeling these graphs is presented, and from this method an efficient L(2, 1)-labeling for Butterfly and CCC networks is derived. Finally we describe a possible generalization of our approach.

  16. LH receptor gene expression is essentially absent in breast tumor tissue: Implications for treatment

    NARCIS (Netherlands)

    T.M. Kuijper (Martijn); K. Ruigrok-Ritstier (Kirsten); M. Verhoef-Post (Miriam); D. Piersma (Djura); M.W.P. Bruysters (Martijn); P.M.J.J. Berns (Els); A.P.N. Themmen (Axel)

    2009-01-01

    textabstractWorldwide, breast cancer is the most frequently occurring malignancy in women. Early age at full term pregnancy has a protective effect against breast cancer. Evidence coming from a rat breast cancer model suggests a possible role for the pregnancy hormone hCG, a ligand of the LH recepto

  17. Dynamics of L-H transition and I-phase in EAST

    DEFF Research Database (Denmark)

    Xu, G. S.; Wang, H. Q.; Xu, M.

    2014-01-01

    The turbulence and flows at the plasma edge during the L-I-H, L-I-L and single-step L-H transitions have been measured directly using two reciprocating Langmuir probe systems at the outer midplane with several newly designed probe arrays in the EAST superconducting tokamak. The E × B velocity, tu...

  18. Single-molecule spectroscopy reveals photosynthetic LH2 complexes switch between emissive states.

    Science.gov (United States)

    Schlau-Cohen, Gabriela S; Wang, Quan; Southall, June; Cogdell, Richard J; Moerner, W E

    2013-07-01

    Photosynthetic organisms flourish under low light intensities by converting photoenergy to chemical energy with near unity quantum efficiency and under high light intensities by safely dissipating excess photoenergy and deleterious photoproducts. The molecular mechanisms balancing these two functions remain incompletely described. One critical barrier to characterizing the mechanisms responsible for these processes is that they occur within proteins whose excited-state properties vary drastically among individual proteins and even within a single protein over time. In ensemble measurements, these excited-state properties appear only as the average value. To overcome this averaging, we investigate the purple bacterial antenna protein light harvesting complex 2 (LH2) from Rhodopseudomonas acidophila at the single-protein level. We use a room-temperature, single-molecule technique, the anti-Brownian electrokinetic trap, to study LH2 in a solution-phase (nonperturbative) environment. By performing simultaneous measurements of fluorescence intensity, lifetime, and spectra of single LH2 complexes, we identify three distinct states and observe transitions occurring among them on a timescale of seconds. Our results reveal that LH2 complexes undergo photoactivated switching to a quenched state, likely by a conformational change, and thermally revert to the ground state. This is a previously unobserved, reversible quenching pathway, and is one mechanism through which photosynthetic organisms can adapt to changes in light intensities.

  19. Carotenoid-bacteriochlorophyll energy transfer in LH2 complexes studied with 10-fs time resolution.

    Science.gov (United States)

    Polli, Dario; Cerullo, Giulio; Lanzani, Guglielmo; De Silvestri, Sandro; Hashimoto, Hideki; Cogdell, Richard J

    2006-04-01

    In this report, we present a study of carotenoid-bacteriochlorophyll energy transfer processes in two peripheral light-harvesting complexes (known as LH2) from purple bacteria. We use transient absorption spectroscopy with approximately 10 fs temporal resolution, which is necessary to observe the very fast energy relaxation processes. By comparing excited-state dynamics of the carotenoids in organic solvents and inside the LH2 complexes, it has been possible to directly evaluate their energy transfer efficiency to the bacteriochlorophylls. In the case of okenone in the LH2 complex from Chromatium purpuratum, we obtained an energy transfer efficiency of etaET2=63+/-2.5% from the optically active excited state (S2) and etaET1=61+/-2% from the optically dark state (S1); for rhodopin glucoside contained in the LH2 complex from Rhodopseudomonas acidophila these values become etaET2=49.5+/-3.5% and etaET1=5.1+/-1%. The measurements also enabled us to observe vibrational energy relaxation in the carotenoids' S1 state and real-time collective vibrational coherence initiated by the ultrashort pump pulses. Our results are important for understanding the dynamics of early events of photosynthesis and relating it to the structural arrangement of the chromophores.

  20. DIBROMOACETIC ACID ATTENUATES A DIMETHYLDITHIOCARBAMATE-INDUCED SUPPRESSION OF THE RAT LH SURGE

    Science.gov (United States)

    DIBROMOACETIC ACID ATTENUATES A DITHIOCARBAMATE-INDUCED SUPPRESSION OF THE LH SURGE IN THE RAT. Jerome M. Goldman, Ashley S. Murr, Angela R. Buckelew, W. Keith McElroy and Janet M. Ferrell. Repro. Toxicol. Div., NHEERL, ORD, US EPA, RTP, NCAt elevated concentrations, the ...

  1. De testosteron produktietest. Een specifieke in vitro biologische bepaling van luteiniserend hormoon (LH)

    NARCIS (Netherlands)

    van Ginkel LA; Loeber JG

    1983-01-01

    Een in vitro biologische bepaling voor luteiniserend hormoon (LH), de testosteron produktietest (TPA) in muize Leydig cellen, werd opgezet. De meting van het geproduceerde testosteron vindt plaats met behulp van een radioimmunochemische methode. De dosis-werkingscurve geeft, indien de testosteron

  2. Slow Tourism: Exploring the discourses

    Directory of Open Access Journals (Sweden)

    J. Guiver

    2016-05-01

    Full Text Available ‘Slow travel’ and ‘slow tourism’ are relatively new, but contested, concepts. This paper examines the meanings ascribed to them in the academic literature and websites targeted at potential tourists. It finds concurrence on aspects of savouring time at the destination and investing time to appreciate the locality, its people, history, culture and products, but detects different emphases. The academic literature stresses the benefits to the destination and global sustainability, while the websites focus on the personal benefits and ways of becoming a ‘slow tourist’. Food and drink epitomise the immersion in and absorption of the destination and the multi-dimensional tourism experience, contrasted with the superficiality of mainstream tourism. The paper discusses whether tourists practising slow tourism without using the label are slow tourists or not.

  3. Increased basal and pulsatile secretion of FSH and LH in young men with 47,XXY or 46,XX karyotypes

    DEFF Research Database (Denmark)

    Aksglaede, L.; Jensen, Rikke Bodin Beck; Carlsen, E.;

    2008-01-01

    basal, pulsatile, and total LH and FSH secretion were associated with significantly more LH peaks per 24 h in comparison with healthy controls. Thus, our data indicate that in patients with Klinefelter syndrome and XX male karyotypes the entire hypothalamic-pituitary-gonadal axis has undergone...

  4. Effect of Photo-Oxidation on Energy Transfer in Light Harvesting Complex (LH2) from Rhodobacter Sphaeroides 601

    Institute of Scientific and Technical Information of China (English)

    LIU Kang-Jun; LIU Wei-Min; YAN Yong-Li; DONG Zhi-Wei; LIU Yuan; XU Chun-He; QIAN Shi-Xiong

    2006-01-01

    @@ We study the photo-oxidation of bacteriochlorophylls (BChls) in peripheral light harvesting complexes (LH2) from rhodobacter sphaeroides by using the steady absorption and the femtosecond pump-probe measurement, to realize the detailed dynamics of LH2 in the presence of photo-oxidation.

  5. The involvement of luteinizing hormone (LH) and Pregnancy-Associated Glycoprotein family (PAG) in pregnancy maintenance in the pig.

    Science.gov (United States)

    Panasiewicz, Grzegorz; Majewska, Marta; Szafrańska, Bozena

    2004-07-01

    The paper presents the effect of in vivo immuno-neutralization of porcine luteinizing hormone (pLH) by species-homologous porcine antiserum (anti-pLH) administrations on pregnancy maintenance and immunodetection of the PAG proteins in precipitated plasma proteins of pregnant gilts. Pregnant gilts were passively immunized with 100 ml of porcine anti-pLH (titer 1:10 000) by multiple intravenous infusions performed from 37(th) to 42(nd) day post coitum (dpc; 12-h intervals). Blood samples of pregnant gilts were taken 12 times daily from 35 until 50 dpc. Concentrations of progesterone (P(4)) and pLH were determined by radioimmunoassays in systemic blood plasma of treated gilts and control pregnant gilts. The immuno-neutralization of peripheral pLH with the use of homologous anti-pLH serum resulted in a significant reduction (ppLH) did not affect the pregnancy maintenance. Thus, the maintenance of mid-pregnancy in gilts may depend also on other than LH luteotrophic factors. In addition, Western analysis of precipitated plasma proteins of pregnant pigs suggests a role of the PAG family during pregnancy in the pig.

  6. A SELF-PRIMING EFFECT OF LHRH ON LH SECRETION IN DISPERSED ANTERIOR PITUITARY CELLS OF ADULT MALE RAT

    Institute of Scientific and Technical Information of China (English)

    QUZhi-Chao; GUOJing; GUOJian

    1989-01-01

    LHRH self-priming effect is simply defmed as an enhancement of LH response to LHRH, i. e., a second challenge with LHRH elicits more LH secretion as compared to the first challenge. The present study is to observe whether this phenomenon exists in perfused anterior pituitary (AP) cells of adult male rat. Dispersed AP cells of adult SD

  7. A STUDY ON SERUM FSH, LH AND PROLACTIN LEVELS AMONG INFERTILE WOMEN

    Directory of Open Access Journals (Sweden)

    Prasad Bheem, Parmar Dinesh, Sharma Nc

    2015-10-01

    Full Text Available Background: Study of hormonal imbalance and its implications in female infertility are an interesting area that requires to be explored in recent time. Hormonal imbalance can associated with irregular menstrual cycle, Amenorrhea, obesity and infertility in women. Other medical conditions such as polycystic ovarian syndrome, Endometriosis, stress, sexually transmitted diseases and chromosomal anomalies may be responsible for infertility in females. Objective: The aim of the present study was to evaluate the serum levels of Follicle Stimulating hormone (FSH, Luteinizing hormone (LH and Prolactin hormone in infertile women that were referred from different infertility clinics and centres. Materials and Methods: This study comprises total 176 female subjects with age ranging from 20 to 40 years and divided in two groups. The total number of 88 infertile women along with 88 fertile women as controls was included for the present study. Serum FSH, LH and Prolactin levels were estimated by enzyme-linked immunosorbent assay (ELISA methods. Results: The results showed maximum infertile women were found between the age group of 30-40 years. The Serum FSH, LH and Prolactin levels among infertile women was 8.77±4.65, 7.64±5.16 and 18.59±7.50 respectively. Whereas, levels of FSH, LH and Prolactin in fertile women showed that 6.71±4.12, 5.66±3.17 and 13.44±5.82 respectively. Conclusion: In this study, we found that the hormone levels have statistically significant with female infertility. The elevated levels of FSH, LH and Prolactin may be one of the important causes for infertility in women.

  8. The unexpected, long-lasting, UV rebrightening of the superluminous supernova ASASSN-15lh

    Science.gov (United States)

    Godoy-Rivera, D.; Stanek, K. Z.; Kochanek, C. S.; Chen, Ping; Dong, Subo; Prieto, J. L.; Shappee, B. J.; Jha, S. W.; Foley, R. J.; Pan, Y.-C.; Holoien, T. W.-S.; Thompson, Todd. A.; Grupe, D.; Beacom, J. F.

    2017-04-01

    Given its peak luminosity and early-time spectra, ASASSN-15lh was classified as the most luminous supernova ever discovered. Here, we report a UV rebrightening of ASASSN-15lh observed with Swift during our follow-up campaign. The rebrightening began at t ≃ 90 d (observer frame) after the primary peak and was followed by a ∼120-d long plateau in the bolometric luminosity, before starting to fade again at t ≃ 210 d. ASASSN-15lh rebrightened in the Swift UV bands by ΔmUVW2 ≃ -1.75 mag, ΔmUVM2 ≃ -1.25 mag and ΔmUVW1 ≃ -0.8 mag, but did not rebrighten in the optical bands. Throughout its initial decline, subsequent rebrightening and renewed decline, the spectra did not show evidence of interactions between the ejecta and circumstellar medium such as narrow emission lines. There are hints of weak Hα emission at late-times, but Margutti et al. have shown that it is narrow line emission consistent with star formation in the host nucleus. By fitting a blackbody, we find that during the rebrightening, the effective photospheric temperature increased from TBB ≃ 11 000 K to TBB ≃ 18 000 K. Over the ∼ 550 d since its detection, ASASSN-15lh has radiated ∼1.7 -1.9 × 1052 erg. Although its physical nature remains uncertain, the evolution of ASASSN-15lh's photospheric radius, its radiated energy and the implied event rate, are all more similar to those of H-poor superluminous supernovae than to tidal disruption events.

  9. Superovulation of goats with purified pFSH supplemented with defined amounts of pLH.

    Science.gov (United States)

    Nowshari, M A; Backers, J F; Holtz, W

    1995-03-01

    The superovulatory response of goats treated with purified pFSH supplemented with 30, 40 or 50% pLH was compared. Sixty-four Boer goat does were synchronized by progestagen-containing ear implant, randomly allotted to 3 groups and, beginning 2 d before implant removal, treated with purified pFSH supplemented with 30, 40 or 50% pLH. Each animal received 16 Armour Units of pFSH administered in 6 descending doses at 12-h intervals. Along with the last 2 injections, the does received 5 mg PGF(2alpha). Embryos were flushed either surgically or after slaughter on Day 5 or 6 after the last day of standing estrus. The percentage of animals responding to treatment was not different among groups treated with pFSH supplemented with 30, 40 or 50% pLH (76, 71 and 63%, respectively). The corresponding data for number of ovulations was 11.3 +/- 1.6, 16.3 +/- 1.8 and 16.4 +/- 2.6, for number of ova and embryos recovered 8.1 +/- 1.9, 12.0 +/- 1.5 and 13.5 +/- 2.9 and for number of transferable embryos 6.6 +/- 1.9, 9.1 +/- 1.5 and 7.1 +/- 2.1 (x +/- SEM). Results confirm the earlier finding of a good response of goats to pFSH preparations with a high FSH:LH ratio, and, although group differences were statistically nonsignificant (P > 0.05), they suggest that supplementation with approximately 40% pLH may be close to the optimum.

  10. The Unexpected, Long-Lasting, UV Rebrightening of the Super-Luminous Supernova ASASSN-15lh

    Science.gov (United States)

    Godoy-Rivera, D.; Stanek, K. Z.; Kochanek, C. S.; Chen, Ping; Dong, Subo; Prieto, J. L.; Shappee, B. J.; Jha, S. W.; Foley, R. J.; Pan, Y.-C.; Holoien, T. W.-S.; Thompson, Todd. A.; Grupe, D.; Beacom, J. F.

    2017-01-01

    Given its peak luminosity and early-time spectra, ASASSN-15lh was classified as the most luminous supernova (SN) ever discovered (Dong et al. 2016).. Here we report a UV rebrightening of ASASSN-15lh observed with Swift during our follow-up campaign. The rebrightening began at t ≃ 90 days (observer frame) after the primary peak and was followed by a ˜120-day long plateau in the bolometric luminosity, before starting to fade again at t ≃ 210 days. ASASSN-15lh rebrightened in the Swift UV bands by ΔmUVW2 ≃ -1.75 mag, ΔmUVM2 ≃ -1.25 mag, and ΔmUVW1 ≃ -0.8 mag, but did not rebrighten in the optical bands. Throughout its initial decline, subsequent rebrightening, and renewed decline, the spectra did not show evidence of interactions between the ejecta and circumstellar medium (CSM) such as narrow emission lines. There are hints of weak Hα emission at late-times, but Margutti et al. (2016) have shown that it is narrow line emission consistent with star formation in the host nucleus. By fitting a blackbody we find that during the rebrightening the effective photospheric temperature increased from TBB ≃ 11000 K to TBB ≃ 18000 K. Over the ˜ 550 days since its detection, ASASSN-15lh has radiated ˜1.7 - -1.9 × 1052 ergs. Although its physical nature remains uncertain, the evolution of ASASSN-15lh's photospheric radius, its radiated energy, and the implied event rate, are all more similar to those of H-poor superluminous supernovae (SLSNe-I) than to tidal disruption events (TDEs).

  11. Effect of exogenous LH pulses on the fate of the first dominant follicle in postpartum beef cows nursing calves.

    Science.gov (United States)

    Duffy, P; Crowe, M A; Boland, M P; Roche, J F

    2000-01-01

    Prolonged postpartum anoestrus in beef cows is due to failure of early dominant follicles to ovulate. It is hypothesized that this failure to ovulate is due to inadequate LH pulse frequency. The objective of this study was to determine whether administration of hourly LH pulses would cause the first dominant follicle to ovulate. In Expt 1, 16 cows received either saline (n = 8) or porcine LH (pLH; 50 micrograms h-1; n = 8) as hourly pulses for 3-5 days from the second day of dominance of the first dominant follicle (day 0). In Expt 2, 21 cows received either saline (n = 7), or 50 micrograms pLH (n = 7) or 100 micrograms pLH (n = 7) as hourly pulses for 3 days. Appropriate ovarian scanning and assays of blood samples were carried out. In Expt 1, the number of dominant follicles that underwent atresia was not affected by increasing the number of LH pulses, but the duration of dominance (days) of the first and second dominant follicles and maximum size (mm) of the second dominant follicle were increased (P pLH pulses (3.1 +/- 1.2 pg ml-1) compared with controls (1.2 +/- 0.2 pg ml-1). Four of eight treated cows had an anovulatory LH surge. The number of follicle waves to first ovulation was not different (P pLH treated cows (3.9 +/- 0.5). In Expt 2, four of seven cows given pulses of 100 micrograms pLH h-1 ovulated the first dominant follicle, and the interval from calving to first ovulation was decreased (P pLH h-1 or control treatments. In conclusion, hourly pulses of pLH from day 1 after dominance of the first dominant follicle in postpartum beef cows can either prolong dominance or induce it to ovulate. This finding supports the hypothesis that LH pulse frequency is a key determinant of the fate of the dominant follicle in the early postpartum period.

  12. LH and hCG Action on the Same Receptor Results in Quantitatively and Qualitatively Different Intracellular Signalling

    Science.gov (United States)

    Casarini, Livio; Lispi, Monica; Longobardi, Salvatore; Milosa, Fabiola; La Marca, Antonio; Tagliasacchi, Daniela; Pignatti, Elisa; Simoni, Manuela

    2012-01-01

    Human luteinizing hormone (hLH) and chorionic gonadotropin (hCG) act on the same receptor (LHCGR) but it is not known whether they elicit the same cellular and molecular response. This study compares for the first time the activation of cell-signalling pathways and gene expression in response to hLH and hCG. Using recombinant hLH and recombinant hCG we evaluated the kinetics of cAMP production in COS-7 and hGL5 cells permanently expressing LHCGR (COS-7/LHCGR, hGL5/LHCGR), as well as cAMP, ERK1/2, AKT activation and progesterone production in primary human granulosa cells (hGLC). The expression of selected target genes was measured in the presence or absence of ERK- or AKT-pathways inhibitors. In COS-7/LHCGR cells, hCG is 5-fold more potent than hLH (cAMP ED50: 107.1±14.3 pM and 530.0±51.2 pM, respectively). hLH maximal effect was significantly faster (10 minutes by hLH; 1 hour by hCG). In hGLC continuous exposure to equipotent doses of gonadotropins up to 36 hours revealed that intracellular cAMP production is oscillating and significantly higher by hCG versus hLH. Conversely, phospho-ERK1/2 and -AKT activation was more potent and sustained by hLH versus hCG. ERK1/2 and AKT inhibition removed the inhibitory effect on NRG1 (neuregulin) expression by hLH but not by hCG; ERK1/2 inhibition significantly increased hLH- but not hCG-stimulated CYP19A1 (aromatase) expression. We conclude that: i) hCG is more potent on cAMP production, while hLH is more potent on ERK and AKT activation; ii) hGLC respond to equipotent, constant hLH or hCG stimulation with a fluctuating cAMP production and progressive progesterone secretion; and iii) the expression of hLH and hCG target genes partly involves the activation of different pathways depending on the ligand. Therefore, the LHCGR is able to differentiate the activity of hLH and hCG. PMID:23071612

  13. In vitro effect of leptin on anterior pituitary cells LH secretory activity during early pregnancy in pig.

    Science.gov (United States)

    Siawrys, G; Gajewska, A

    2017-03-28

    Leptin modulates reproductive activity but its potential influence on LH secretion from anterior pituitary (AP) cells during implantation period in pigs (days 14-16 of pregnancy) remained unexplored. This study focused on determination whether leptin affects basal and GnRH-induced LH secretion and intracellular accumulation and whether leptin receptor (OB-Rb) mRNA is expressed in the AP gland during implantation in pigs. Four individual AP glands were developed into separate primary cultures. 2×105 cells/ml were preincubated (72 h) and next, for 3.5 h, experimentally treated with GnRH (100 ng/ml), leptin (10-11, 10-9, 10-7, 10-6 M) alone, or given in respective combinations with GnRH. In the AP gland, OB-Rb mRNA expression was determined by real-time PCR method. Leptin activated LH secretion and its concentration-dependent effect was observed as stimulation shown in a full range tested (culture 1) and exhibited only at 10-6 M (culture 2). A pooled data analysis revealed that basal LH secretion increased at 10-9, 10-7 and 10-6 M, but GnRH-induced LH release decreased at 10-6 M. Leptin down-regulated GnRH-induced LH secretion in all cultures, but only culture 3 exhibited sensitivity for all concentrations tested. Basal LH accumulation was activated in culture 1 (at 10-11 M) and inhibited in culture 4 (at 10-9 M). In the presence of GnRH leptin up-regulated LH accumulation with individual culture leptin-sensitivity (culture 1-3), while down-regulated LH accumulation in culture 4. Obtained data indicate that OB-Rb mRNA is expressed in the AP gland and leptin alone and in combination with GnRH specifically modulates LH activity during early pregnancy in pigs.

  14. The celiac ganglion modulates LH-induced inhibition of androstenedione release in late pregnant rat ovaries

    Directory of Open Access Journals (Sweden)

    Rastrilla Ana M

    2006-12-01

    Full Text Available Abstract Background Although the control of ovarian production of steroid hormones is mainly of endocrine nature, there is increasing evidence that the nervous system also influences ovarian steroidogenic output. The purpose of this work was to study whether the celiac ganglion modulates, via the superior ovarian nerve, the anti-steroidogenic effect of LH in the rat ovary. Using mid- and late-pregnant rats, we set up to study: 1 the influence of the noradrenergic stimulation of the celiac ganglion on the ovarian production of the luteotropic hormone androstenedione; 2 the modulatory effect of noradrenaline at the celiac ganglion on the anti-steroidogenic effect of LH in the ovary; and 3 the involvement of catecholaminergic neurotransmitters released in the ovary upon the combination of noradrenergic stimulation of the celiac ganglion and LH treatment of the ovary. Methods The ex vivo celiac ganglion-superior ovarian nerve-ovary integrated system was used. This model allows studying in vitro how direct neural connections from the celiac ganglion regulate ovarian steroidogenic output. The system was incubated in buffer solution with the ganglion and the ovary located in different compartments and linked by the superior ovarian nerve. Three experiments were designed with the addition of: 1 noradrenaline in the ganglion compartment; 2 LH in the ovarian compartment; and 3 noradrenaline and LH in the ganglion and ovarian compartments, respectively. Rats of 15, 19, 20 and 21 days of pregnancy were used, and, as an end point, the concentration of the luteotropic hormone androstenedione was measured in the ovarian compartment by RIA at various times of incubation. For some of the experimental paradigms the concentration of various catecholamines (dihydroxyphenylalanine, dopamine, noradrenaline and adrenaline was also measured in the ovarian compartment by HPLC. Results The most relevant result concerning the action of noradrenaline in the celiac ganglion

  15. Production of specific antisera for radioimmunoassay of human luteinizing hormone (LH) in the presence of human chorionic gonadotropin (hCG). [/sup 125/I

    Energy Technology Data Exchange (ETDEWEB)

    Thorell, J.I.; Jeppsson, S.; Holmstrom, B.

    1976-09-01

    A specific radioimmunoassay for LH, which measures plasma LH in the presence of human chorionic gonadotropin (hCG) is described. Rabbits were immunized with highly purified native LH. One of the antisera with a difference in its reactivity against LH and hCG was further purified by affinity chromatography on a column with hCG coupled to Sepharose 4B. The adsorbed antiserum and /sup 125/I-LH was used in a double antibody assay. The LH standard (MRC/68/40) efficiently inhibited the binding of /sup 125/I-LH, and the standard curve showed a sensitivity of 0.5 ng/ml in the sample. hCG up to 10,000 ng/ml did not inhibit the binding of /sup 125/I-LH. The plasma level of LH in pregnant women in the first trimester was low (1.3 +- 0.1 ng/ml). When LH was measured in fertile or menopausal women with or without stimulation with LH/FSH releasing hormone (LH-RH)/sup x/ the results agreed to those found with our conventional LH-assay based on antiserum against hCG.

  16. Membrane-initiated actions of estradiol (E2 in the regulation of LH secretion in ovariectomized (OVX ewes

    Directory of Open Access Journals (Sweden)

    Oakley Amy E

    2010-05-01

    Full Text Available Abstract Background We demonstrated that E2 conjugated to BSA (E2BSA induces a rapid membrane-initiated inhibition of LH secretion followed hours later by a slight increase in LH secretion. Whether these actions of E2BSA are restricted to the pituitary gland and whether the membrane-initiated pathway of E2BSA contributes to the up-regulation of the number of GnRH receptors during the positive feedback effect of E2 were evaluated here. We have shown that the suppression of LH secretion induced by E2 and E2BSA is the result of a decreased responsiveness of the pituitary gland to GnRH. In this study we further tested the ability of E2BSA to decrease the responsiveness of the pituitary gland to GnRH under the paradigm of the preovulatory surge of LH induced by E2. Methods For the first experiment GnRH and LH secretions were determined in samples of pituitary portal and jugular blood, respectively, in ewes treated with 12 mg E2BSA. In the second experiment, the number of GnRH receptors was quantified in ewes 12 h after administration of 25 micrograms E2 (the expected time for the increase in the number of GnRH receptors and the positive feedback effect of E2 in LH secretion or 12 mg E2BSA. In the third experiment, the preovulatory-like surge of LH was characterized in ewes injected with 25 micrograms E2 alone or followed 8 h later (before the beginning of the LH surge with 60 mg E2BSA. Results a the decrease in LH secretion induced by E2BSA was not accompanied by changes in the pulsatile pattern of GnRH, b E2BSA increased the number of GnRH receptors, and c the presence of E2BSA in E2-treated ewes delayed the onset, reduced the length, and decreased the amount of LH released during the preovulatory surge of LH. Conclusions a the rapid suppression of LH secretion induced by E2BSA is mediated only via a direct action on the pituitary gland, b E2 acting via a membrane-initiated pathway contributes to increase the number of GnRH receptors and, c

  17. Birth control - slow release methods

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007555.htm Birth control - slow release methods To use the sharing features on this page, please enable JavaScript. Certain birth control methods contain man-made forms of hormones. These ...

  18. Slow light in flight imaging

    CERN Document Server

    Wilson, Kali; Gariepy, Genevieve; Henderson, Robert; Howell, John; Faccio, Daniele

    2016-01-01

    Slow-light media are of interest in the context of quantum computing and enhanced measurement of quantum effects, with particular emphasis on using slow-light with single photons. We use light-in-flight imaging with a single photon avalanche diode camera-array to image in situ pulse propagation through a slow light medium consisting of heated rubidium vapour. Light-in-flight imaging of slow light propagation enables direct visualisation of a series of physical effects including simultaneous observation of spatial pulse compression and temporal pulse dispersion. Additionally, the single-photon nature of the camera allows for observation of the group velocity of single photons with measured single-photon fractional delays greater than 1 over 1 cm of propagation.

  19. PENGARUH PEMBERIAN MONOSODIUM GLUTAMAT (MSG PADA TIKUS JANTAN (Rattus Norvegicus TERHADAP FSH DAN LH

    Directory of Open Access Journals (Sweden)

    Zulkarnain Edward

    2010-09-01

    Full Text Available AbstrakKemajuan teknologi informasi membawa dampak terhadap perubahan gaya hidup masyarakat, termasuk perubahan pola konsumsi makanan yang lebih banyak mengkonsumsi jenis makanan cepat saji, makanan kemasan dan makanan awetan yang belakangan ini semakin banyak dijual dipasar tradisional dan swalayan. Penggunaan bahan tambahan makanan sering dijumpai, salah satunya adalah bahan penyedap yang banyak sekali digunakan seperti senyawa L-asam glutamat yang digunakan dalam bentuk garam yaitu monosodium glutamat (MSG. Berbagai merk dagang MSG telah dikenal dimasyarakat secara luas seperti ajinomoto, vetsin, micin, sasa, miwon dan sebagainya.MSG adalah garam monosodium dengan asam glutamat yang sering digunakan sebagai bahan penyedap masakan untuk merangsang selera makan. Pemberian MSG mengakibatkan gangguan hormonal pada hewan coba, ion glutamat dalam sirkulasi portal akan mempengaruhi hipotalamus dalam memproduksi GnRH yang selanjutnya akan mengganggu hipofise anterior dalam memproduksi FSH dan LH. Fungsi FSH adalah untuk bekerja pada tubulus seminiferus terutama pada sel sertoli untuk meningkatkan spermatogenesis, sedangkan LH berfungsi pada sel Leydig untuk mengatur sekresi testosteron.Penelitian ini bersifat eksperimen dengan rancangan post only group design. Penelitian dilakukan di laboratorium Biologi dan laboratorium Biokimia Fakultas Kedokteran Unand Padang dari tanggal 20 Desember 2009 sampai 30 Februari 2010. Populasi adalah tikus putih jantan strain Jepang (Rattus norvegicus yang berasal dari laboratorium Fakultas Matematika dan Ilmu Pengetahuan Alam Unand. Sampel berjumlah 20 ekor dibagi atas 4 kelompok dengan satu kelompok kontrol dan tiga kelompok perlakuan. Dosis MSG yang digunakan yaitu P1= 4800 mg/kgbb/hari, P2=7200 mg/kgbb/hari dan P3= 9600 mg/kgbb/hari diberikan peroral sebanyak dua siklus epitel seminiferus. Analisa dengan uji Anova dengan derajat kepercayaan 95% dan jika bermakna dilanjutkan dengan uji Multiple Comparissons jenis

  20. Enhanced Lower Hybrid Current Drive Experiments on HT-7 Tokamak

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Effective Lower Hybrid Current Driving (LHCD) and improved confinement exper-iments in higher plasma parameters (Ip > 200 kA, ne> 2×1013 cm-3, Te ≥ 1 keⅤ) havebeen curried out in optimized LH wave spectrum and plasma parameters in HT-7 supercon-ducting tokamak. The dependence of current driving efficiency on LH power spectrum, plasmadensity ne and toroidal magnetic field BT has been obtained under optimal conditions. A goodCD efficiency was obtained at higher plasma current and higher electron density. The improve-ment of the energy confinement time is accompanied with the increase in line averaged electrondensity, and in ion and electron temperatures. The highest current driving efficiency reachedηCD = IpneR/PRF ≈ 1.05 × 1019 Am-2/W. Wave-plasma coupling was sustained in a good stateand the reflective coefficient was less than 5%. The experiments have also demonstrated the abilityof LH wave in the start-up and ramp-up of the plasma current. The measurement of the temporaldistribution of plasma parameter shows that lower hybrid leads to a broader profile in plasmaparameter. The LH power deposition profile and the plasma current density profile were modeledwith a 2D Fokker-Planck code corresponding to the evolution process of the hard x-ray detectorarray.

  1. Discontinuation of rLH two days before hCG may increase the number of oocytes retrieved in IVF

    Directory of Open Access Journals (Sweden)

    Session Donna R

    2010-03-01

    Full Text Available Abstract Background Administration of recombinant luteinizing hormone (rLH in controlled ovarian hyperstimulation may benefit a subpopulation of patients. However, late follicular phase administration of high doses of rLH may also reduce the size of the follicular cohort and promote monofollicular development. Methods To determine if rLH in late follicular development had a negative impact on follicular growth and oocyte yield, IVF patients in our practice who received rFSH and rLH for the entire stimulation were retrospectively compared with those that had the rLH discontinued at least two days prior to hCG trigger. Results The two groups had similar baseline characteristics before stimulation with respect to age, FSH level and antral follicle count. However, the group which had the rLH discontinued at least two days prior to their hCG shot, had a significantly higher number of oocytes retrieved, including a higher number of MII oocytes and number of 2PN embryos. Conclusions When using rLH for controlled ovarian hyperstimulation, administering it from the start of stimulation and stopping it in the late follicular phase, at least two days prior to hCG trigger, may increase oocyte and embryo yield.

  2. Ca(2+)-binding reduces conformational flexibility of RC-LH1 core complex from thermophile Thermochromatium tepidum.

    Science.gov (United States)

    Jakob-Grun, Selma; Radeck, Jara; Braun, Paula

    2012-03-01

    The light-harvesting complex, LH1, of thermophile purple bacteria Thermochromatium tepidum consists of an array of α- and β-polypeptides which assemble the photoactive bacteriochlorophyll and closely interact with the membrane-lipids. In this study, we investigated the effect of calcium and manganese ions on the protein structure and thermostability of the reaction centre (RC)-LH1/lipid complex. The binding of Ca(2+), but not Mn(2+) is shown to shift the LH1 Q ( y ) absorption maximum from ~889 to 915 nm and to significantly raise the thermostability of the RC-LH1 complex. The ATR-FTIR spectra indicate that interaction of Ca(2+) as monitored by the carboxylates' vibration of aspartate residues, but not Mn(2+) induces changes in the α-helix packing arrangement. The reduced rate of (1)H/(2)H exchange of proteins' amide protons shows that the accessibility to (2)H(2)O is significantly lowered in Ca(2+)-substituted RC-LH1/lipid complexes. In particular, exchange with the associated lipid molecules, is significantly retarded. These results suggest that the thermostability of the RC-LH1 complex is raised by the distinct interaction with calcium cations which reduces the RC-LH1/lipid dynamics, particularly, at the membrane-water interface.

  3. Stationary magnetic shear reversal during Lower Hybrid experiments in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Litaudon, X.; Arslanbekov, R.; Hoang, G.T.; Joffrin, E.; Kazarian-Vibert, F.; Moreau, D.; Peysson, Y.; Bibet, P. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Ferron, J.; Kupfer, K. [General Atomics, San Diego, CA (United States)] [and others

    1996-01-01

    Stable and stationary states with hollow current density profiles have been achieved with Lower Hybrid Current Drive (LHCD) during Lower Hybrid (LH) wave accessibility experiments. By analysing the bounded propagation domain in phase space which naturally limits the central penetration and absorption of the waves, off-axis LH power deposition has been realized in a reproducible manner. The resulting current density profile modifications have led to a global confinement enhancement attributed to the formation of an internal `transport barrier` in the central reversed shear region where the electron thermal diffusivity is reduced to its neoclassical collisional level. The multiple-pass LH wave propagation in the weak Landau damping and reversed magnetic shear regime is also investigated in the framework of a statistical theory and the experimental validation of this theory is discussed. (author). 37 refs.

  4. The 21st LH Gray Conference (June 4-6, 2008)

    Energy Technology Data Exchange (ETDEWEB)

    West, C. M. L. [Univ. of Manchester (United Kingdom); Martin, C. J. [Gartnavel Royal Hospital, Glasgow (United Kingdom); Sutton, D. G. [Ninewells Hospital and Medical School, Dundee (United Kingdom); Wright, E. G. [Ninewells Hospital and Medical School, Dundee (United Kingdom)

    2009-01-12

    The 21st LH Gray Conference, organised by the LH Gray Trust with the Society for Radiological Protection, brought together international experts in radiobiology, epidemiology and risk assessment, and scientists involved in diagnostic and therapeutic radiation exposure. The meeting - held in Edinburgh, Scotland 4-6 June 2008 - aimed to raise awareness, educate and share knowledge of important issues in radiation protection. A distinguished group of speakers discussed topics which included: non-targeted effects of radiation, exposure to high natural background radiation, non-cancer effects in Japanese bomb survivors, lessons learnt from Chernobyl, radiation in the workplace, biokinetic modelling, uncertainties in risk estimation, issues in diagnostic medical exposures, lessons leant from the polonium-210 incidence and how the radiobiology-radiation oncology community is needed to help society prepare for potential future acts of radiation terrorism. The conference highlighted the importance, relevance and topicality of radiobiology today.

  5. Do FSH/LH ratio and gonadal hormone levels predict clinical improvement in postmenopausal schizophrenia women?

    Science.gov (United States)

    González-Rodríguez, Alexandre; Bernardo, Miquel; Penadés, Rafael; Arias, Bárbara; Ruiz Cortés, Victoria; Seeman, Mary V; Catalán, Rosa

    2017-07-12

    Menopause is a process characterized by a decline in estrogen levels and is therefore a period of biological vulnerability for psychotic relapse in women with schizophrenia. Our goal was to correlate not only gonadal hormone levels but also follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels with improvement in specific clinical symptoms. Thirty-seven acutely ill postmenopausal schizophrenia women with a newly initiated, clinically determined change in antipsychotic medication participated in a 12-week prospective observational outcome study. Scales used were the PANSS scale for psychotic symptoms, the PSP for functioning, and CGI for global clinical impression. Circulating FSH, LH, estradiol, progesterone, and testosterone serum levels were determined by chemiluminescent immunoassay. Partial correlational analyses were performed along with a Bonferroni significance correction (p schizophrenia symptom domains, we recommend further investigation of pituitary, adrenal, and gonadal hormone ratios as potential markers of clinical improvement in this population.

  6. THE MOST LUMINOUS SUPERNOVA ASASSN-15LH: SIGNATURE OF A NEWBORN RAPIDLY ROTATING STRANGE QUARK STAR

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Z. G.; Wang, S. Q.; Wang, J. S. [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Wang, L. J. [Key Laboratory of Space Astronomy and Technology, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Yu, Y. W., E-mail: dzg@nju.edu.cn [Institute of Astrophysics, Central China Normal University, Wuhan 430079 (China)

    2016-02-01

    In this paper we show that the most luminous supernova discovered very recently, ASASSN-15lh, could have been powered by a newborn ultra-strongly magnetized pulsar, which initially rotates near the Kepler limit. We find that if this pulsar is a neutron star, its rotational energy could be quickly lost as a result of gravitational-radiation-driven r-mode instability; if it is a strange quark star (SQS), however, this instability is highly suppressed due to a large bulk viscosity associated with the nonleptonic weak interaction among quarks and thus most of its rotational energy could be extracted to drive ASASSN-15lh. Therefore, we conclude that such an ultra-energetic supernova provides a possible signature for the birth of an SQS.

  7. Regulation of post-Golgi LH3 trafficking is essential for collagen homeostasis

    Science.gov (United States)

    Banushi, Blerida; Forneris, Federico; Straatman-Iwanowska, Anna; Strange, Adam; Lyne, Anne-Marie; Rogerson, Clare; Burden, Jemima J.; Heywood, Wendy E.; Hanley, Joanna; Doykov, Ivan; Straatman, Kornelis R.; Smith, Holly; Bem, Danai; Kriston-Vizi, Janos; Ariceta, Gema; Risteli, Maija; Wang, Chunguang; Ardill, Rosalyn E.; Zaniew, Marcin; Latka-Grot, Julita; Waddington, Simon N.; Howe, S. J.; Ferraro, Francesco; Gjinovci, Asllan; Lawrence, Scott; Marsh, Mark; Girolami, Mark; Bozec, Laurent; Mills, Kevin; Gissen, Paul

    2016-01-01

    Post-translational modifications are necessary for collagen precursor molecules (procollagens) to acquire final shape and function. However, the mechanism and contribution of collagen modifications that occur outside the endoplasmic reticulum and Golgi are not understood. We discovered that VIPAR, with its partner proteins, regulate sorting of lysyl hydroxylase 3 (LH3, also known as PLOD3) into newly identified post-Golgi collagen IV carriers and that VIPAR-dependent sorting is essential for modification of lysines in multiple collagen types. Identification of structural and functional collagen abnormalities in cells and tissues from patients and murine models of the autosomal recessive multisystem disorder Arthrogryposis, Renal dysfunction and Cholestasis syndrome caused by VIPAR and VPS33B deficiencies confirmed our findings. Thus, regulation of post-Golgi LH3 trafficking is essential for collagen homeostasis and for the development and function of multiple organs and tissues. PMID:27435297

  8. Successful treatment of unilateral cryptorchid boys risking infertility with LH-RH analogue

    Directory of Open Access Journals (Sweden)

    Faruk Hadziselimovic

    2008-06-01

    Full Text Available INTRODUCTION: Infertility is the primary concern for boys with uni- or bilateral undescended testes. An early and seemingly successful orchiopexy does not improve fertility in a substantial number of cryptorchid males. We confirmed that LH-RH analogue (LH-RHa treatment induces an increase in and maturation of the germ cells; however, it was uncertain if treatment would improve the chance of fertility later in life. MATERIALS AND METHODS: Thirty unilateral cryptorchid boys, with an average age of 3 years at the time of surgery, were included in the study. Testicular biopsy showed that they had impaired testicular maturation and were therefore at high risk for infertility. Fifteen of the 30 unilateral cryptorchid boys were treated with 10 µg LH-RHa (Buserelin nasal spray, administered on alternate days for a period of 6 months, following orchiopexy. The control group consisted of 15 cryptorchid boys who had been treated by Schoemakers type of orchiopexy, alone. After puberty, the ejaculates of both groups were analyzed. RESULTS: All males in the untreated group were severely oligospermic, with 20% being azoospermic. In contrast, 86% of the treated ex-cryptorchid males had a sperm concentration within the normal range; this was significantly different from the sperm concentration found in the untreated group (p = 0.000008. CONCLUSION: For the first time, we demonstrate that infertility in cryptorchidism can be successfully corrected when suitably treated with a LH-RHa. Sperm parameters normalized following therapy in the majority of cryptorchid males who, untreated, would have remained infertile. This innovative hormonal treatment will have a profound effect on the current recommended surgical treatment of boys with undescended testes.

  9. Space-based LH 2 propellant storage system: subscale ground testing results

    Science.gov (United States)

    Liggett, M. W.

    An orbital cryogenic liquid storage facility will be one of the essential elements of the US Space Program to realize the benefits of space-based cryogenic propulsion vehicles such as NASA's space transfer vehicle (STV) for transporting personnel and scientific packages from a space station in low earth orbit (LEO) to geosynchronous orbit (GEO), the moon and beyond. Long-term thermal control of LH 2 and LO 2 storage cryotanks is a key technical objective for many NASA and SDI programmes. Improved retention using refrigeration, boil-off vapour-cooled shields (VCSs), multilayer superinsulation (MLI) and para-ortho (P-O) hydrogen conversion are the required state-of-the-art techniques. The cryotank system level development testing (CSLDT) programme has supported the development of these technologies. Under the programme, trade studies and analyses were followed by the design and construction of a subscale LH 2 storage facility test article for steady-state and transient thermal tests. A two-stage gaseous helium (GHe) refrigerator was integrated with the test article and used to reduce boil-off and/or decrease the time required between passive test configuration steady-state conditions. The LH 2 tank, mounted in a vacuum chamber, was thermally shielded from the chamber wall by MLI blankets and two VCSs. The VCSs were cooled with either LH 2 boil-off gas (through an optional P-O converter) or refrigerated GHe. The CSLDT test article design, assembly and results from 400 hours of thermal tests are presented along with important conclusions. A comparison of predicted and measured steady-state boil-off rates is provided for 10 test configurations, and the system time constant is addressed. Also presented are some of the unique issues and challenges encountered during these tests that are related to instrumentation and control.

  10. [Cytological changes in hypophysis of immatur rats after administration of anti-LH antibodies (author's transl)].

    Science.gov (United States)

    Perez, R L; Bardia-Deu, R; Monastirsky, R A; Lawzewitsch, I V

    1975-01-01

    In the present work, cytological changes produced in rats' pars distalis were studied by administration of anti-LH antibodies. The anti-LH sera was obtained by active immunization of adult rabbits using bovine LH hormone with Freund's complete adjuvant. Newborn albino Wistar male and female rats were daily and subcutaneously inoculated with 0.1 ml. to 0.8 ml of anti-LH sera from the first 24 hr. on during 5 weeks. For controls, a similar schedule of inoculations with normal rabbit serum was used. At weekly intervals during the treatment, 5 lots of rats were sacrificed and the rest after a recovery period of 95 days. At the end of the 2nd week of immunization, both male and female animals showed degranulated gonadotroph cells in the central part of the pars distalis; at the 3rd week these cells were hypertrophied and presented developed Golgi complex. At the 4th week, the first large vacuoles of "castration" were seen in the gonadotroph cells of male pars distalis, besides in the females the degranulation of gonadotrophs continued. During the last week of treatment, the gonadotrophs of the male animals presented a highly dilated Golgi complex, more "castration-like cells" and numerous mitosis figures. The gonadotrophs of females pars distalis presented degranulation, but not vacuoles. After the recovery period the gonadotrophs of male rats were similar to those of the control hypophisis and did not show castration vacuoles in their cytoplasm. In female rats, the gonadotrophic cells showed "castration-like vacuoles" and a raised number of mitosis cells compared to control pituitaries. The significance of these findings will be discussed.

  11. Development of advanced materials composites for use as insulations for LH2 tanks

    Science.gov (United States)

    Lemons, C. R.; Salmassy, O. K.

    1973-01-01

    A study of thread-reinforced polyurethane foam and glass fabric liner, serving as internally bonded insulation for space shuttle LH2 tanks, is reported. Emphasis was placed on an insulation system capable of reentry and multiple reuse in the shuttle environment. The optimized manufacturing parameters associated with each element of the composite are established and the results, showing successful completion of subscale system evaluation tests using the shuttle flight environmental requirements, are given.

  12. Simulations of the L-H transition on experimental advanced superconducting Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Weiland, Jan [Department Applied Physics, Chalmers University of Technology and Euratom-VR Association, S41296 Gothenburg (Sweden)

    2014-12-15

    We have simulated the L-H transition on the EAST tokamak [Baonian Wan, EAST and HT-7 Teams, and International Collaborators, “Recent experiments in the EAST and HT-7 superconducting tokamaks,” Nucl. Fusion 49, 104011 (2009)] using a predictive transport code where ion and electron temperatures, electron density, and poloidal and toroidal momenta are simulated self consistently. This is, as far as we know, the first theory based simulation of an L-H transition including the whole radius and not making any assumptions about where the barrier should be formed. Another remarkable feature is that we get H-mode gradients in agreement with the α – α{sub d} diagram of Rogers et al. [Phys. Rev. Lett. 81, 4396 (1998)]. Then, the feedback loop emerging from the simulations means that the L-H power threshold increases with the temperature at the separatrix. This is a main feature of the C-mod experiments [Hubbard et al., Phys. Plasmas 14, 056109 (2007)]. This is also why the power threshold depends on the direction of the grad B drift in the scrape off layer and also why the power threshold increases with the magnetic field. A further significant general H-mode feature is that the density is much flatter in H-mode than in L-mode.

  13. Solvation effect of bacteriochlorophyll excitons in light-harvesting complex LH2.

    Science.gov (United States)

    Urboniene, V; Vrublevskaja, O; Trinkunas, G; Gall, A; Robert, B; Valkunas, L

    2007-09-15

    We have characterized the influence of the protein environment on the spectral properties of the bacteriochlorophyll (Bchl) molecules of the peripheral light-harvesting (or LH2) complex from Rhodobacter sphaeroides. The spectral density functions of the pigments responsible for the 800 and 850 nm electronic transitions were determined from the temperature dependence of the Bchl absorption spectra in different environments (detergent micelles and native membranes). The spectral density function is virtually independent of the hydrophobic support that the protein experiences. The reorganization energy for the B850 Bchls is 220 cm(-1), which is almost twice that of the B800 Bchls, and its Huang-Rhys factor reaches 8.4. Around the transition point temperature, and at higher temperatures, both the static spectral inhomogeneity and the resonance interactions become temperature-dependent. The inhomogeneous distribution function of the transitions exhibits less temperature dependence when LH2 is embedded in membranes, suggesting that the lipid phase protects the protein. However, the temperature dependence of the fluorescence spectra of LH2 cannot be fitted using the same parameters determined from the analysis of the absorption spectra. Correct fitting requires the lowest exciton states to be additionally shifted to the red, suggesting the reorganization of the exciton spectrum.

  14. Testosterone and LH Seric Level Dynamics in Male Rats after Potassium Dichromate Intake (Two Generation Study

    Directory of Open Access Journals (Sweden)

    Jelena Rankov

    2010-05-01

    Full Text Available The aim of this study was the evaluation of potassium dichromate impact on biochemical biomarkers for testicular function (serum testosterone and LH level (two generations experiment. Males and females from F0 generation were exposed to potassium dichromate three months before mating. F1 generation was represented by male pups, resulted from F0 generation, exposed to potassium dichromate in utero, in suckling period (via milk and water and until sexual maturity. All the animals were divided in four groups: three experimental and one control, exposed to Cr VI trough drinking water, as follows E1: 25 ppm (LOAEL; E2: 50 ppm: E3: 75 ppm; control group received tap water without chromium content. The study was performed in compliance with national and international law regarding animal welfare and ethics in animal experiments. In male rats, from F0 and F1 generation, exposure to Cr VI determined: significant decrease of testosterone and significant increase of LH seric level in all experimental groups comparative to control one, indirectly, respectively, directly correlated to exposure level. Comparative to F0 generation, in F1 generation seric testosterone level was lower, significantly only in E1 and E3 groups, and LH seric level was significantly higher.

  15. ASASSN-15lh: A Superluminous Ultraviolet Rebrightening Observed by Swift and Hubble

    CERN Document Server

    Brown, Peter J; Cooke, Jeff; Olaes, Melanie; Quimby, Robert M; Baade, Dietrich; Gehrels, Neil; Hoeflich, Peter; Maund, Justyn; Mould, Jeremy; Patat, Ferdinando; Wang, Lifan; Wheeler, J Craig

    2016-01-01

    We present and discuss ultraviolet (UV) and optical photometry from the Ultraviolet/Optical Telescope (UVOT) and X-ray limits from the X-Ray Telescope on Swift and imaging polarimetry and UV/optical spectroscopy with the Hubble Space Telescope (HST) of ASASSN-15lh. It has been classified as a hydrogen-poor superluminous supernova (SLSN I) more luminous than any other supernova observed. From the polarimetry we determine that the explosion was only mildly asymmetric. We find the flux of ASASSN-15lh to increase strongly into the UV, with a UV luminosity a hundred times greater than the hydrogen-rich, UV-bright SLSN II SN~2008es. A late rebrightening -- most prominent at shorter wavelengths -- is seen about two months after the peak brightness, which by itself is as bright as a superluminous supernova. ASASSN-15lh is not detected in the X-rays in individual observations or when the data are summed into two separate bins for the early phase and the rebrightening. The HST UV spectrum during the rebrightening is do...

  16. [Secondary amenorrhea and LH hypersecretion. An unusual report of a granulosa cell ovarian tumor].

    Science.gov (United States)

    Arteaga, E; Campusano, C; Fernández, C

    1993-04-01

    Granulosa cell ovarian tumors are infrequent. Since they originate from the gonadal stroma, they retain a high secretory potential and some of their clinical manifestations may be secondary to the production of sexual steroids. A 36 year old woman with an ovarian tumor presenting as a secondary amenorrhea is reported. This patient had a positive progesterone test and her hormonal profile showed a maintained LH hypersecretion (> 75 mUl/ml) which, joined to the presence of a hypophyseal microadenoma lead to suspect the presence of a gonadotrophin secreting tumor. The absence of LH response to TRH and its adequate suppression using oral contraceptives discarded this diagnosis. The histopathology of the excised ovarian tumor demonstrated that it is was a granulosa cell tumor. The physiopathological explanation of the case is based on the maintained levels of estrogens produced by the tumor that, through a positive feed-back mechanism similar to that of the polycystic ovary syndrome, produced a tonic LH elevation and GnRH hyper response. After the tumor excision, ovulatory cycles resumed and the patient became pregnant, facts that confirm the postulated hypothesis.

  17. The Unexpected, Long-Lasting, UV Rebrightening of the Super-Luminous Supernova ASASSN-15lh

    CERN Document Server

    Godoy-Rivera, D; Kochanek, C S; Chen, Ping; Dong, Subo; Prieto, J L; Shappee, B J; Jha, S W; Foley, R J; Pan, Y -C; Holoien, T W -S; Thompson, Todd A; Grupe, D; Beacom, J F

    2016-01-01

    ASASSN-15lh is the most luminous supernova (SN) ever discovered (Dong et al. 2016), based on its peak bolometric luminosity. Here we report a UV rebrightening of ASASSN-15lh observed with {\\it Swift} during our follow-up photometric campaign. The rebrightening began at $t \\simeq 90$ days (observer frame) after the primary peak and was followed by a $\\sim 120$-day long plateau in the bolometric luminosity, before starting to fade again at $t\\simeq 210$ days. The SN rebrightened in the {\\it Swift} UV bands by $\\Delta m_{UVW2} \\simeq -1.75$ mag, $\\Delta m_{UVM2} \\simeq -1.25$ mag, and $\\Delta m_{UVW1} \\simeq -0.8$ mag, but did not rebrighten in the optical bands. Throughout its initial decline, subsequent rebrightening, and renewed decline, the spectra of ASASSN-15lh did not show evidence of interactions between the ejecta and circumstellar medium (CSM) such as narrow emission lines. There are hints of weak, broad, transient H$\\alpha$ emission at late times, but the feature could also be an artifact. By fitting ...

  18. Synchronization of ovulation in cyclic gilts with porcine luteinizing hormone (pLH) and its effects on reproductive function.

    Science.gov (United States)

    Degenstein, K L; O'Donoghue, R; Patterson, J L; Beltranena, E; Ambrose, D J; Foxcroft, G R; Dyck, M K

    2008-10-15

    The overall objective was to evaluate the use of porcine luteinizing hormone (pLH) for synchronization of ovulation in cyclic gilts and its effect on reproductive function. In an initial study, four littermate pairs of cyclic gilts were given altrenogest (15 mg/d for 14 d). Gilts received 500 microg cloprostenol (Day 15), 600 IU equine chorionic gonadotropin (eCG) (Day 16) and either 5mg pLH or saline (Control) 80 h after eCG. Blood samples were collected every 4h, from 8h before pLH/saline treatment to the end of estrus. Following estrus detection, transcutaneous real-time ultrasonography and AI, all gilts were slaughtered 6d after the estimated time of ovulation. Peak plasma pLH concentrations (during the LH surge), as well as the amplitude of the LH surge, were greater in pLH-treated gilts than in the control (P=0.01). However, there were no significant differences between treatments in the timing and duration of estrus, or the timing of ovulation within the estrous period. In a second study, 45 cyclic gilts received altrenogest for 14-18d, 600 IU eCG (24h after last altrenogest), and 5mg pLH, 750 IU human chorionic gonadotropin (hCG), or saline, 80 h after eCG. For gilts given pLH or hCG, the diameter of the largest follicle before the onset of ovulation (mean+/-S.E.M.; 8.1+/-0.2 and 8.1+/-0.2mm, respectively) was smaller than in control gilts (8.6+/-0.2mm, P=0.05). The pLH and hCG groups ovulated sooner after treatment compared to the saline-treated group (43.2+/-2.5, 47.6+/-2.5 and 59.5+/-2.5h, respectively; PpLH-treated gilts. Embryo quality (total cell counts and embryo diameter) was not significantly different among groups. In conclusion, pLH reliably synchronized ovulation in cyclic gilts without significantly affecting embryo quality.

  19. Efficiency of superstimulatory protocol P-36 associated with the administration of eCG and LH in Nelore cows.

    Science.gov (United States)

    Oliveira, A C S; Mattos, M C C; Bastos, M R; Trinca, L A; Razza, E M; Satrapa, R A; Sartori, R; Barros, Ciro M

    2014-09-15

    Recent work with P-36 demonstrates that the replacement of the last two doses of Follicle-Stimulating Hormone (FSH) with equine chorionic gonadotropin (eCG) increases embryo yields. However, it is unclear if the positive effect of eCG is related to its FSH-like activity, LH-like activity, or both. This study aimed to verify the replacement of eCG with pLH on the last day of superstimulatory treatment. Twenty-five Nelore cows were allocated to four groups: P-36 (control), P-36/eCG, P-36/LH2, and P-36/LH4. All animals underwent four treatments in a crossover design. The control group cows were superstimulated with decreasing doses of porcine Follicle-Stimulating Hormone (pFSH, 133 mg, im). In the P-36/eCG, P-36/LH2, and P-36/LH4 groups, the last two doses of pFSH were replaced in the former group by two doses of eCG (200 IU each dose, im) and in the latter two groups by two doses of pLH (1 and 2 mg each dose, im), respectively. Donors received fixed-time artificial insemination 12 and 24 hours after pLH. Embryo flushing was performed on D16. Data were analyzed by ANOVA (Proc Mixed, SAS). There was a trend of decreasing ovulation rate when comparing groups LH2 and eCG (P = 0.06). However, there was no significant difference in the mean number of viable embryos among groups P-36 (3.3 ± 0.7), P-36/eCG (4.5 ± 0.5), P-36/LH2 (3.7 ± 0.8), and P-36/LH4 (4.2 ± 1.0). It is concluded that the replacement of eCG by pLH on the last day of superstimulatory treatment can be performed with no significant variation in the production of viable embryos.

  20. Combined beta FSH and beta LH response to TRH in patients with clinically non-functioning pituitary adenomas.

    Science.gov (United States)

    Somjen, D; Tordjman, K; Kohen, F; Baz, M; Razon, N; Ouaknine, G; Stern, N

    1997-05-01

    'Paradoxical' responses of LH, FSH, alpha-subunits and beta LH to TRH have previously been reported in individuals with clinically non-functioning pituitary tumours (NFT). The present study was designed to assess the in vivo and in vitro responses of beta FSH to TRH in NFT. We further examined the possibility that a TRH challenge with combined measurement of beta FSH and beta LH will identify a common anomalous secretory pattern in patients with NFT. Forty patients with NFT underwent a standard TRH test (400 micrograms intravenously). Blood samples for the determination of beta FSH, beta LH, FSH and LH were collected prior to TRH as well as 15, 30, 45, 60 and 90 minutes following injection. Additionally, cultured adenomatous cells from eight to these patients were exposed to TRH in the absence and presence of octreotide and gonadotropin subunits were determined. TRH elicited a marked rise in circulating beta FSH in 29 of 40 individuals and in beta LH in 28 of 36 patients with NFT. In a subgroup of eight individuals whose tumours were harvested during surgery and cultured for 7-21 days, TRH increased beta FSH or beta LH and alpha-subunit release in cultured adenomatous cells in all cases, including tumours from subjects not responding to TRH in vivo. In this subgroup of patients octreotide inhibited basal beta FSH secretion but not basal beta LH secretion both in vivo and in primary cultures of NFT cells. Both the in vivo and in vitro beta FSH, beta LH and alpha-subunit responses to TRH were entirely inhibited by octreotide. In all, 38 of the 40 subjects could be identified by either elevated basal beta FSH or beta LH levels and/or an abnormal rise in either beta FSH or beta LH in response to TRH. The measurement of basal and TRH-stimulated beta-FSH and beta-LH levels identifies an abnormal hormonal secretory pattern in the vast majority (> 90%) of patients with clinically nonfunctioning pituitary tumours.

  1. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  2. The Association Between LH Serum Levels at the time of hCG Injection and Clinical Pregnancy during IVF

    Directory of Open Access Journals (Sweden)

    Budi Wiweko

    2015-12-01

    Full Text Available Some studies showed that recombinant follicle stimulating hormone (r-FSH administration without LH supplementation has a good success rate on in vitro fertilization (IVF. However, LH role in IVF has been controversial. This study was conducted to evaluate the association between serum LH levels at the time of hCG injection and clinical pregnancy during IVF. This retrospective study included 136 patients underwent long protocol IVF from January 2005 to December 2009 in Yasmin Clinic, Cipto Mangunkusumo Hospital, Jakarta. The controlled ovarian hyper-stimulation protocol used in this study was gonadotropin-releasing hormone (GnRH agonist and r-FSH.  Serum LH level was measured on the day of hCG administration and the outcome evaluated was the clinical pregnancy following IVF cycles. There were 32 IVF cycles resulted in pregnancy out of 136 cycles (23.5%. There was significant difference between serum LH levels on the day of hCG administration and clinical pregnancy outcome (p=0.036. LH serum level cut-off value of ≥1.050 IU/l was the best value to predict pregnancy outcome with 62.5% sensitivity, 59.4% specificity, 83.3% positive predictive value, and 32.76% negative predictive value. It was concluded that there was an association between serum LH levels at the time of hCG injection and clinical pregnancy during IVF. Keywords: IVF cycles, LH levels serum, hCG administration   Hubungan Kadar LH saat Penyuntikan hCG dengan Kejadian Kehamilan pada Fertilisasi In vitro Abstrak Pemberian follicles stimulating hormone rekombinan (r-FSH tanpa suplementasi LH memiliki tingkat keberhasilan fertilisasi in vitro (FIV yang baik namun, peran LH pada FIV masih kontroversial. Tujuan penelitian ini adalah untuk mengevaluasi hubungan antara kadar serum LH pada hari penyuntikan hCG dengan kehamilan klinis selama FIV. Penelitian retrospektif ini melibatkan 136 perempuan yang menjalani FIV siklus pertama dengan protokol panjang mulai bulan Januari 2005 sampai

  3. The Potential of/for 'Slow': Slow Tourists and Slow Destinations

    Directory of Open Access Journals (Sweden)

    J. Guiver

    2016-05-01

    Full Text Available Slow tourism practices are nothing new; in fact, they were once the norm and still are for millions of people whose annual holiday is spent camping, staying in caravans, rented accommodation, with friends and relations or perhaps in a second home, who immerse themselves in their holiday environment, eat local food, drink local wine and walk or cycle around the area. So why a special edition about slow tourism? Like many aspects of life once considered normal (such as organic farming or free-range eggs, the emergence of new practices has highlighted differences and prompted a re-evaluation of once accepted practices and values. In this way, the concept of ‘slow tourism’ has recently appeared as a type of tourism that contrasts with many contemporary mainstream tourism practices. It has also been associated with similar trends already ‘branded’ slow: slow food and cittaslow (slow towns and concepts such as mindfulness, savouring and well-being.

  4. Advances in modeling of lower hybrid current drive

    Science.gov (United States)

    Peysson, Y.; Decker, J.; Nilsson, E.; Artaud, J.-F.; Ekedahl, A.; Goniche, M.; Hillairet, J.; Ding, B.; Li, M.; Bonoli, P. T.; Shiraiwa, S.; Madi, M.

    2016-04-01

    First principle modeling of the lower hybrid (LH) current drive in tokamak plasmas is a longstanding activity, which is gradually gaining in accuracy thanks to quantitative comparisons with experimental observations. The ability to reproduce simulatenously the plasma current and the non-thermal bremsstrahlung radial profiles in the hard x-ray (HXR) photon energy range represents in this context a significant achievement. Though subject to limitations, ray tracing calculations are commonly used for describing wave propagation in conjunction with Fokker-Planck codes, as it can capture prominent features of the LH wave dynamics in a tokamak plasma-like toroidal refraction. This tool has been validated on several machines when the full absorption of the LH wave requires the transfer of a small fraction of power from the main lobes of the launched power spectrum to a tail at a higher parallel refractive index. Conversely, standard modeling based on toroidal refraction only becomes more challenging when the spectral gap is large, except if other physical mechanisms may dominate to bridge it, like parametric instabilities, as suggested for JET LH discharges (Cesario et al 2004 Phys. Rev. Lett. 92 175002), or fast fluctuations of the launched power spectrum or ‘tail’ LH model, as shown for Tore Supra (Decker et al 2014 Phys. Plasma 21 092504). The applicability of the heuristic ‘tail’ LH model is investigated for a broader range of plasma parameters as compared to the Tore Supra study and with different LH wave characteristics. Discrepancies and agreements between simulations and experiments depending upon the different models used are discussed. The existence of a ‘tail’ in the launched power spectrum significantly improves the agreement between modeling and experiments in plasma conditions for which the spectral gap is large in EAST and Alcator C-Mod tokamaks. For the Alcator C-Mod tokamak, the experimental evolution of the HXR profiles with density suggests

  5. 基于LH-OAT的SWMM模型参数敏感性分析%An Analysis of Parameter Sensitivity of SWMM Model Based on LH-OAT Method

    Institute of Scientific and Technical Information of China (English)

    朱嘉祺; 徐向阳; 何爽

    2014-01-01

    为了消除SWMM模型计算过程中的不确定性,明确参数对径流模拟的影响,进行了参数敏感性分析.通过LH-OAT敏感性分析方法,辨析出不同参数在昭通市应用时对径流模拟结果的影响程度,确定对其影响较大的若干敏感参数,为参数的率定提供参考.研究结果表明对径流系数影响最大的参数是入渗衰减系数,对洪峰流量影响最大的参数是不渗透性.提高了SWMM模型在金沙江流域应用的可靠性.

  6. Dose from slow negative muons.

    Science.gov (United States)

    Siiskonen, T

    2008-01-01

    Conversion coefficients from fluence to ambient dose equivalent, from fluence to maximum dose equivalent and quality factors for slow negative muons are examined in detail. Negative muons, when stopped, produce energetic photons, electrons and a variety of high-LET particles. Contribution from each particle type to the dose equivalent is calculated. The results show that for the high-LET particles the details of energy spectra and decay yields are important for accurate dose estimates. For slow negative muons the ambient dose equivalent does not always yield a conservative estimate for the protection quantities. Especially, the skin equivalent dose is strongly underestimated if the radiation-weighting factor of unity for slow muons is used. Comparisons to earlier studies are presented.

  7. Diffusion theory of slow responses

    Institute of Scientific and Technical Information of China (English)

    李景德; 陈敏; 郑凤; 周镇宏

    1997-01-01

    When an action is applied to a macroscopic substance, there is a particular sort of slow response he sides the well-known fast response. Using diffusion theory, the characteristics of slow response in dielectric, elastic, piezoelectric, and pyroelectric relaxation may he explained A time domain spectroscopy method suitable for slow and fast responses in linear and nonlinear effects is given. Every relaxation mechanism contributes a peak in differential spectroscopy, and its position, height, and line shape show the dynamical properties of the mechanism The method of frequency domain spectroscopy is suitable only for linear fast response. Time domain spectroscopy is another nonequiv-alent powerful method. The theory is confirmed by a lot of experimental data

  8. Obsessional slowness: a case study.

    Science.gov (United States)

    Lam, Wendy; Wong, Karen W; Fulks, Mary-Ann; Holsti, Liisa

    2008-10-01

    Obsessional slowness is a rare psychiatric disorder with few treatment options and limited research to date. Some suggest that targeted behavioural interventions may reduce the time taken for functional daily activities. To examine whether a behavioural intervention would reduce the amount of time taken for an adolescent with obsessional slowness to walk to class. A single-subject A-B-A withdrawal design was incorporated into this case study. The treatment involved one-to-one pacing and prompting during the subject's walk to gym class. Walking times to gym class were measured during a baseline phase, during a one-month treatment phase, and during a post-treatment follow-up phase. The subject's walking times decreased during the treatment phase. Post-treatment walking times suggested a carry-over effect. This study adds to the sparse evidence on treatments for obsessional slowness and suggests occupation-based treatment options.

  9. Crystallization and preliminary X-ray diffraction analysis of the peripheral light-harvesting complex LH2 from Marichromatium purpuratum.

    Science.gov (United States)

    Cranston, Laura J; Roszak, Aleksander W; Cogdell, Richard J

    2014-06-01

    LH2 from the purple photosynthetic bacterium Marichromatium (formerly known as Chromatium) purpuratum is an integral membrane pigment-protein complex that is involved in harvesting light energy and transferring it to the LH1-RC `core' complex. The purified LH2 complex was crystallized using the sitting-drop vapour-diffusion method at 294 K. The crystals diffracted to a resolution of 6 Å using synchrotron radiation and belonged to the tetragonal space group I4, with unit-cell parameters a=b=109.36, c=80.45 Å. The data appeared to be twinned, producing apparent diffraction symmetry I422. The tetragonal symmetry of the unit cell and diffraction for the crystals of the LH2 complex from this species reveal that this complex is an octamer.

  10. Progesterone (CIDR)-based timed AI protocols using GnRH, porcine LH or estradiol cypionate for dairy heifers: ovarian and endocrine responses and pregnancy rates.

    Science.gov (United States)

    Ambrose, J D; Kastelic, J P; Rajamahendran, R; Aali, M; Dinn, N

    2005-10-15

    The overall objective was to compare the efficacy of GnRH, porcine LH (pLH) and estradiol cypionate (ECP), in a modified Ovsynch/fixed-time AI (FTAI) protocol that included a controlled internal drug [progesterone] release (CIDR) device. In Experiment 1, heifers received a CIDR on Day -10, and PGF (25mg) on Day -3. At CIDR insertion, heifers received 100 microg of GnRH (n=6), 0.5mg of ECP (n=6), 5.0mg of pLH (n=6) or 2 mL of saline (n=7); these treatments were repeated on Day -1, except for ECP, that was repeated on Day -2, concurrent with CIDR-removal. The 5.0 mg pLH was the least effective with a longer interval to ovulation than the other groups combined (102 versus 64 h; PpLH compared to all other groups (4.5 versus 10.3 ng/mL; PpLH (n=6; pLH-low), 25.0 mg pLH (n=6, pLH-high), or 100 microg GnRH (n=5; control). Heifers in the pLH-high group had greater (PpLH treatments did not differ (P>0.10). Area under the curve for LH (ng/32 h) was at least 50% greater (PpLH-treated heifers compared to GnRH-treated heifers (mean, 41.3, 56.3 and 20.3 for pLH-low, pLH-high and GnRH, respectively). Ovulation occurred in 15 of 17 heifers. Progesterone concentrations were higher on Days 9 and 14 in heifers given 25mg of pLH, suggesting enhanced CL function. In Experiment 3, 240 heifers were assigned to CIDR-based Ovsynch/FTAI protocols. The first and second hormonal treatments (with an intervening PGF treatment on Day -3) were GnRH/GnRH (100 microg), ECP/ECP (0.5 mg), pLH/pLH (12.5 mg) or GnRH/ECP, respectively; pregnancy rates were 58.7, 66.1, 45.9 and 48.3%, respectively (ECP/ECP>both pLH/pLH and GnRH/ECP; P

  11. A novel carboxyl-terminal heptapeptide initiates the regulated secretion of LH from unique sub-domains of the ER.

    Directory of Open Access Journals (Sweden)

    Albina Jablonka-Shariff

    Full Text Available The coordinated secretion of LH and FSH are critical for reproductive functions. After translocation into the endoplasmic reticulum (ER, their biosynthetic routes diverge at a determinative step prior to sorting in the regulated (LH and constitutive (FSH secretion pathways. Recently, we identified a C-terminal heptapeptide sequence, present only in the LHβ subunit, as a critical signal for entry of the LH dimer into the regulated pathway. We showed that an LHβ mutant lacking the heptapeptide (LHβΔT assembled more efficiently with the α subunit than wild-type LHβ subunit, and this LHΔT dimer was secreted constitutively. Thus, an association exists between the presence of the C-terminal heptapeptide and sorting of the LH heterodimer to the regulated pathway. To study how this delayed LHβ subunit assembly is related to the trafficking of LH, we exploited the single subunit transfection model in rat somatotrope-derived GH3 cells with the use of immunofluorescence confocal microscopy. The LHβ subunit showed a distinct immunofluorescent localization as compared to the FSHβ subunit and LHβ mutants. The wild-type LHβ subunit exhibited a perinuclear staining corresponding to the ER/nuclear envelope region. In contrast, the wild-type FSHβ subunit and the mutants LHβΔT and LHβL119A displayed no detectable perinuclear staining; only peripheral ER puncta were observed. Also, no perinuclear fluorescence was detected in cells expressing the LH heterodimer. We propose that the C-terminal heptapeptide is responsible for delayed heterodimer assembly within an ER sub-domain of the nuclear envelope, as an early partitioning event necessary for the entrance of LH into the regulated secretory pathway, whereas FSHβ does not traverse the nuclear envelope region. These data suggest that, at least for LH, the molecular decision to enter the regulated secretory pathway is a pre-Golgi event controlled by the novel C-terminal heptapeptide.

  12. Construction and Characterization of B850-Only LH2 Energy Transfer System in Purple Bacteria%紫细菌B800缺失LH2能量传递模型的构建及性质

    Institute of Scientific and Technical Information of China (English)

    李凯; 赵春贵; 岳慧英; 杨素萍; 曲音波; 焦念志

    2015-01-01

    To seek microscopic molecular mechanism of energy transfer and complex reconstitution in the photosynthesis ,the conditions for construction of B850‐only peripheral light‐harvesting complex (LH2) and their properties were investigated using absorption ,fluorescence spectroscopy ,molecular sieve chromatography ,ultrafiltration and sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS‐PAGE) from the purple bacteria .The results indicated that bacteriochlorophylls (BChl) of B800 incu‐bated in 10 mmo · L -1 Tris‐HCl (pH 8.0) buffer are selectively released from their binding sites of LH2 of Rhodobacter azoto‐formans(A‐LH2)by0.08% (W/V)SDS.B850‐onlyA‐LH2wasconstructedafterremovingfreeBChlmixingwith10% meth‐yl alcohol by ultrafiltration .B850 BChl was released after A‐LH2 was incubated for 240 min in dark at room temperature (RT) . While BChl of B800 incubated in pH 1.9 buffer were selectively released from their binding sites of LH 2 of Rhodopseudomonas palustris (P‐LH2) .The authors acquired two components using molecular sieve chromatography .Free BChl of one component was not removed and self‐assembled to P‐LH2 .The other removed free BChl and B850‐only P‐LH2 was constructed .B850 un‐changed after P‐LH2 was incubated .P‐LH2 αandβsubunits have different molecular weights ,but those of A‐LH2 are in the contrary .It is concluded that B850‐only P‐LH2 is more stable than A‐LH2 .The enigmatic split of the B800 absorption band was not observed in these LH2 ,but we acquired two kinds of B800‐released LH2 from Rhodopseudomonas palustris .The authors’ results may provide a new light to separate homogeneous Apoprotein LH 2 .%构建B800缺失L H2对于阐明光合作用中光能传递的分子机制与捕光复合体组装机制具有重要意义。采用吸收光谱、荧光光谱、分子筛层析、超滤和SDS‐PAGE等方法研究了紫细菌两个典型种外周捕光复合体(LH2)约800 nm特征光谱(B800

  13. Cloning and structural and expressional characterization of BcpLH gene preferentially expressed in folding leaf of Chinese cabbage

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Vegetative growth of Chinese cabbage undergoes the four successive stages which are characterized with the definite types of juvenile,rosette,folding and head leaves.From shoot tips of Chinese cabbage at early folding stage,we constructed a cDNA library and screened the differentially expressed cDNA clones using the cDNAs derived from developing folding leaves and rosette leaves as probes.One complete length of cDNA clone is designated as BcpLH.Computer alignment matched BcpLH to the domains of double-stranded RNA binding (DBRM) and the homologous regions were recognized between BcpLH and human and mouse double-stranded RNA-binding protein TRBP.PCR expression analysis shows that during vegetative growth BcpLH gene was expressed preferentially in folding leaves at folding stage.Transcripts of BcpLH gene were increased when plants were sprayed with IAA.It is deduced that BcpLH gene may be related to initiation of folding leaf and leafy head and induced by auxin in the aspect of transcriptional expression.

  14. LH/hCG-Receptor Expression May Have a Negative Prognostic Value in Low-Risk Endometrial Cancer.

    Science.gov (United States)

    Noci, Ivo; Sorbi, Flavia; Mannini, Luca; Projetto, Elisabetta; Pillozzi, Serena; Ghizzoni, Viola; Lottini, Tiziano; Moncini, Daniela; Baroni, Gianna; Mungai, Francesco; Arcangeli, Annarosa; Fambrini, Massimiliano

    2016-01-01

    A 51 year-old woman was diagnosed with endometrial cancer (EC) and underwent surgical staging. Pathological evaluation showed a 2 cm × 1 cm G2 endometrioid EC with a 30% myometrial deep invasion (FIGO Stage 1A). The patient was classified as low risk of recurrence, and no adjuvant treatment was offered. Six months after surgery, the patient developed an early vescico-vaginal recurrence, and chemotherapy treatment was started. Few months later, a subsequent involvement of vaginal wall, ileum, and omentum was detected, and the patient underwent second surgery. LH/hCG-receptor (LH/hCG-R) expression has been previously reported to be associated with an invasive phenotype in EC cells. Moreover, in a preclinical mouse model of EC behaves as a prometastatic molecular device. We analyzed the expression level of LH/hCG-R in cancer specimens collected during surgeries. Molecular and immunohistochemical analyses showed a strong expression of both mRNA and protein for LH/hCG-R in all specimens. LH/hCG-R expression may be assessed together with other clinicopathological parameters in order to better predict the risk of recurrence in low-risk EC patients. Further clinical trials are warranted in order to validate LH/hCG-R as biomarker in EC.

  15. 缓释氮肥施用量对超级杂交早稻株两优02产量和生理特性的影响%Effects of Application Amount of Slow-release Nitrogen Fertilizer on Physiological Characteristics and Grain Yield of Early Super Hybrid Rice Zhuliangyou 02

    Institute of Scientific and Technical Information of China (English)

    周静; 孟桂元; 龙继锐; 马国辉; 万宜珍

    2011-01-01

    在常规栽培和优化栽培模式下,分别设置施氮量折合成纯氮0,105,142.5,180 kg/hm2的4个缓释氮肥用量处理,研究了缓释氮肥用量对超级杂交早稻株两优02产量和生理特性的影响.结果表明:在优化栽培模式下,各施氮量处理的产量均高于相应的常规栽培处理,其中纯氮用量142.5 kg/hm2的处理产量最高,而常规栽培各处理的产量则随施氮量的增加而提高;在优化栽培和常规栽培模式下,各时期叶片中的过氧化氢酶(CAT)活性、可溶性糖含量和根系活力均以施氮量180 kg/hm2的处理较高;施用纯氮142.5 kg/hm2的处理乳熟期-成熟期叶片中能保持较高的超氧化物歧化酶(SOD)活性和较低的丙二醛(MDA)含量,有利于延缓水稻功能叶片的衰老.%The effects of application amount of slow-release nitrogen fertilizer were studied on the physiological characteristics and grain yield of Zhuliangyou 02, a widely-used early-cropping super hybrid rice variety. The research was conducted with two cultivation modes, I. E. , the optimized and conventional modes, and four nitrogen application levels of the slow-release nitrogen fertilizer at the pure N rates of 0 ( N0) , 105 ( N1 ) , 142.5 ( N2) and 180 kg/hm2 ( N3 ) , respectively. The results showed that the grain yields of all N rates under the optimized cultivation mode were higher than those of the conventional cultivation mode, with the rate of 142. 5 kg/hm2 (N2) yielding highest at 8.05 t/hm2. However, under the conventional cultivation mode, the grain yields of different treatments increased with the N rates applied. Under both optimized and conventional cultivation modes, the treatment of N3 with the N rate of 180 kg/hm2 had highest CAT activity, soluble sugar content and root activity in the whole growing period from full tillering to ripening stages among all treatments of nitrogen application levels. Moreover, the treatment of N2 (142.5 kg/hm2) maintained a higher SOD

  16. Periodic solutions and slow manifolds

    NARCIS (Netherlands)

    Verhulst, F.

    2006-01-01

    After reviewing a number of results from geometric singular perturbation theory, we give an example of a theorem for periodic solutions in a slow manifold. This is illustrated by examples involving the van der Pol-equation and a modified logistic equation. Regarding nonhyperbolic transitions we disc

  17. CFD investigation of thermal and pressurization performance in LH2 tank during discharge

    Science.gov (United States)

    Wang, Lei; Li, Yanzhong; Li, Cui; Zhao, Zhixiang

    2013-10-01

    Predictions of thermal and pressurization performance in a liquid hydrogen (LH2) tank during liquid discharge is of significance to the design and optimization of a rocket pressurization system. In this paper, a computational fluid dynamic (CFD) model is introduced to simulate the pressurized discharge event of LH2 tank. The wall region together with the fluid region is simultaneously considered as the computational domain, and low-Re k-ε model is applied to account for the fluid-wall heat exchange effect. Liquid-vapor phase change effect is also involved in the model. Comparison of the numerical results with existing experimental data suggests that the CFD model has a good adaptability in pressurization computation. Detailed characteristics, such as pressurant gas requirement, pressure altering history, and temperature distribution inside the tank, can be obtained by the model. The difference of pressurant gas, selecting helium or vapor H2, may result in the variations in pressure and temperature histories. Pressurization by vapor H2 supplies a higher pressure and also a temperature rise, which is significant to consider the selection of pressurant gas. The influences of phase change effect and injector structure on pressurization behaviors are also analyzed. The computational results show that liquid-vapor phase change has a slight influence on the pressurization behaviors. Significant pressure decay at the beginning stage of process may occur in the case of no-diffuser injector application since the incoming gas is excessively cooled by cold LH2. The results show that the present CFD model has a good adaptability in the prediction of pressurization behaviors and is a useful tool for the design and optimization of a pressurization system.

  18. LOX/LH2 propulsion system for launch vehicle upper stage, test results

    Science.gov (United States)

    Ikeda, T.; Imachi, U.; Yuzawa, Y.; Kondo, Y.; Miyoshi, K.; Higashino, K.

    1984-01-01

    The test results of small LOX/LH2 engines for two propulsion systems, a pump fed system and a pressure fed system are reported. The pump fed system has the advantages of higher performances and higher mass fraction. The pressure fed system has the advantages of higher reliability and relative simplicity. Adoption of these cryogenic propulsion systems for upper stage of launch vehicle increases the payload capability with low cost. The 1,000 kg thrust class engine was selected for this cryogenic stage. A thrust chamber assembly for the pressure fed propulsion system was tested. It is indicated that it has good performance to meet system requirements.

  19. Early postnatal treatment of hypogonadotropic hypogonadism with recombinant human FSH and LH

    DEFF Research Database (Denmark)

    Main, Katharina M; Schmidt, Ida M; Toppari, Jorma

    2002-01-01

    postnatally, to mimic the physiological development, would improve testicular growth and fertility potential later in life. DESIGN: Our patient presented with micropenis. Serum hormone concentrations were measured monthly after delivery: LH and testosterone were undetectable, and FSH and inhibin B were below...... to values within normal limits (0.7-1.88 IU/l, 0.17-3.24 IU/l, 121-268 pg/ml and 40-55 pmol/l respectively), whereas serum testosterone remained undetectable. Penile length increased from 1.6 to 2.4 cm and testicular volume, assessed by ultrasound, increased by 170%. No significant adverse events were...

  20. Hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    West, J.G.W. [Electrical Machines (United Kingdom)

    1997-07-01

    The reasons for adopting hybrid vehicles result mainly from the lack of adequate range from electric vehicles at an acceptable cost. Hybrids can offer significant improvements in emissions and fuel economy. Series and parallel hybrids are compared. A combination of series and parallel operation would be the ideal. This can be obtained using a planetary gearbox as a power split device allowing a small generator to transfer power to the propulsion motor giving the effect of a CVT. It allows the engine to run at semi-constant speed giving better fuel economy and reduced emissions. Hybrid car developments are described that show the wide range of possible hybrid systems. (author)

  1. Partially Deglycosylated Equine LH Preferentially Activates β-Arrestin-Dependent Signaling at the Follicle-Stimulating Hormone Receptor

    Science.gov (United States)

    Wehbi, Vanessa; Tranchant, Thibaud; Durand, Guillaume; Musnier, Astrid; Decourtye, Jérémy; Piketty, Vincent; Butnev, Vladimir Y.; Bousfield, George R.; Crépieux, Pascale; Maurel, Marie-Christine; Reiter, Eric

    2010-01-01

    Deglycosylated FSH is known to trigger poor Gαs coupling while efficiently binding its receptor. In the present study, we tested the possibility that a deglycosylated equine LH (eLHdg) might be able to selectively activate β-arrestin-dependent signaling. We compared native eLH to an eLH derivative [i.e. truncated eLHβ (Δ121-149) combined with asparagine56-deglycosylated eLHα (eLHdg)] previously reported as an antagonist of cAMP accumulation at the FSH receptor (FSH-R). We confirmed that, when used in conjunction with FSH, eLHdg acted as an antagonist for cAMP accumulation in HEK-293 cells stably expressing the FSH-R. Furthermore, when used alone at concentrations up to 1 nm, eLHdg had no detectable agonistic activity on cAMP accumulation, protein kinase A activity or cAMP-responsive element-dependent transcriptional activity. At higher concentrations, however, a weak agonistic action was observed with eLHdg, whereas eLH led to robust responses whatever the concentration. Both eLH and eLHdg triggered receptor internalization and led to β-arrestin recruitment. Both eLH and eLHdg triggered ERK and ribosomal protein (rp) S6 phosphorylation at 1 nm. The depletion of endogenous β-arrestins had only a partial effect on eLH-induced ERK and rpS6 phosphorylation. In contrast, ERK and rpS6 phosphorylation was completely abolished at all time points in β-arrestin-depleted cells. Together, these results show that eLHdg has the ability to preferentially activate β-arrestin-dependent signaling at the FSH-R. This finding provides a new conceptual and experimental framework to revisit the physiological meaning of gonadotropin structural heterogeneity. Importantly, it also opens a field of possibilities for the development of selective modulators of gonadotropin receptors. PMID:20107152

  2. Partially deglycosylated equine LH preferentially activates beta-arrestin-dependent signaling at the follicle-stimulating hormone receptor.

    Science.gov (United States)

    Wehbi, Vanessa; Tranchant, Thibaud; Durand, Guillaume; Musnier, Astrid; Decourtye, Jérémy; Piketty, Vincent; Butnev, Vladimir Y; Bousfield, George R; Crépieux, Pascale; Maurel, Marie-Christine; Reiter, Eric

    2010-03-01

    Deglycosylated FSH is known to trigger poor Galphas coupling while efficiently binding its receptor. In the present study, we tested the possibility that a deglycosylated equine LH (eLHdg) might be able to selectively activate beta-arrestin-dependent signaling. We compared native eLH to an eLH derivative [i.e. truncated eLHbeta (Delta121-149) combined with asparagine56-deglycosylated eLHalpha (eLHdg)] previously reported as an antagonist of cAMP accumulation at the FSH receptor (FSH-R). We confirmed that, when used in conjunction with FSH, eLHdg acted as an antagonist for cAMP accumulation in HEK-293 cells stably expressing the FSH-R. Furthermore, when used alone at concentrations up to 1 nM, eLHdg had no detectable agonistic activity on cAMP accumulation, protein kinase A activity or cAMP-responsive element-dependent transcriptional activity. At higher concentrations, however, a weak agonistic action was observed with eLHdg, whereas eLH led to robust responses whatever the concentration. Both eLH and eLHdg triggered receptor internalization and led to beta-arrestin recruitment. Both eLH and eLHdg triggered ERK and ribosomal protein (rp) S6 phosphorylation at 1 nM. The depletion of endogenous beta-arrestins had only a partial effect on eLH-induced ERK and rpS6 phosphorylation. In contrast, ERK and rpS6 phosphorylation was completely abolished at all time points in beta-arrestin-depleted cells. Together, these results show that eLHdg has the ability to preferentially activate beta-arrestin-dependent signaling at the FSH-R. This finding provides a new conceptual and experimental framework to revisit the physiological meaning of gonadotropin structural heterogeneity. Importantly, it also opens a field of possibilities for the development of selective modulators of gonadotropin receptors.

  3. Downregulation of LH and FSH receptors after hCG and eCG treatments in the porcine oviduct.

    Science.gov (United States)

    Małysz-Cymborska, I; Andronowska, A

    2016-10-01

    The influence of induction of ovulation and superovulation with eCG and hCG on LH and FSH receptor levels in porcine oviducts on day 3 postcoitum was studied. In experiment I, gilts were assigned into cyclic (control; n = 5) and inseminated (n = 5) groups. In experiment II, there were 3 groups of animals: inseminated (n = 5), induced ovulation/inseminated (750 IU eCG, 500 IU hCG; n = 5) and superovulated/inseminated (1500 IU eCG, 1000 IU hCG; n = 5) gilts. Oviduct tissues were collected 3 d after insemination or PBS infusion. The messenger RNA (mRNA) expression of FSH receptor (FSHR) and luteinizing hormone/chorionic gonadotropin receptor (LH/CGR) was measured by real-time reverse transcription PCR and protein levels using Western blots. Localization of LH/CGR and FSHR-positive cells was studied by immunohistochemical staining. Insemination by itself did not influence mRNA and protein levels of LH/CGR. However, FSHR mRNA expression in the isthmus and ampulla of the oviduct was affected by insemination (P hCG and eCG did not affect LH/CGR and FSHR mRNA expression, either in the isthmus or in the ampulla. Nevertheless, superovulation decreased LH/CGR protein level in the oviductal ampulla (P hCG, especially in high doses, can change LH/CGR and FSHR levels in porcine oviducts. This may in turn alter many signaling pathways, eg, PGs or vascular endothelial growth factor synthesis, and consequently disturb the oviductal environment, with possible detrimental effects on fertilization and/or embryonic development. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Effect of kisspeptin-10, LH and hCG on serum testosterone concentrations in stallions, donkeys and mules.

    Science.gov (United States)

    Akhtar, Rana Waseem; Shah, Syed Aftab Hussain; Qureshi, Irfan Zia

    2017-07-21

    This study was conducted to determine the response of serum testosterone (T) in male equines (stallions, donkeys and mules) after administering intravenous doses of kisspeptin-10 (KP-10), human chorionic gonadotropin (hCG) and luteinizing hormone (LH) and saline as a control. The animals were divided into four groups of three each: Group I, 3 ml of 0.95% saline; Group II, 50 μg KP-10; Group III, 2500 IU hCG and group IV, 400 μg LH. The administration of KP-10 and hCG to stallions resulted in a significant increase in serum T concentration at 240 min; whereas it was significantly higher at 30, 60, 120, and 240 min with LH treatment as compared to pre-dose concentrations. Both KP-10 and hCG significantly elevated the T concentrations in donkeys at 120 and 240 min, respectively; whereas it was significantly higher at 60, 120, and 240 min with LH treatment as compared to pre-dose concentration. Both KP-10 and LH elevated T in donkeys at 240 min as compared to the control and hCG concentrations. After 120 and 240 min, T concentrations in mules were higher (p hCG and LH as compared to the control. In conclusion, the administration of KP-10, hCG and LH elevate the serum T concentration in normal male equines. It is suggested that KP-10 may be useful in situations where an increase in T is desired. Further work is required to determine the effect of KP-10 on T in male equids with reproductive abnormalities before it can be used in clinical situations. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. [The response of free alpha-subunit of glycoprotein hormones to LH-RH administration (author's transl)].

    Science.gov (United States)

    Hamamoto, T; Nishimura, R; Ashitaka, Y; Tojo, S

    1982-05-20

    The responses of immunoreactive free alpha-subunit of glycoprotein hormones to LH-RH administration were studied in normal men and women, and in patients with hypergonadotropic hypogonadism, hypogonadotropic hypogonadism, trophoblastic disease and isolated ectopic alpha-subunit producing tumor. In patients with hypergonadotropic hypergonadism, basal levels of serum alpha-subunit were elevated and the responses to LH-RH were also excessive compared to those of normal men and women. Conversely, in hypogonadotropic hypogonadism, basal levels of alpha-subunit were significantly low and its response to LH-RH was barely detectable. The response of alpha-subunit to constant intravenous infusion of LH-RH (1 microgram/kg/h) was studied in 4 normal men. Both LH and alpha-subunit revealed biphasic patterns of elevation. Its releasing pattern suggests the possibility that two pools of gonadotropin are involved in the production and secretion of alpha-subunit. In patients with trophoblastic disease secreting low levels of hCG (18 mIU/ml), the responses of alpha-subunit as well as pituitary gonadotropin to LH-RH were normal. However, in cases of high concentrations of hCG (1000 mIU/ml), the responses of alpha-subunit and gonadotropin were suppressed. After the administration of LH-RH to a patient with an isolated ectopic alpha-subunit producing tumor, the serum concentration of pituitary gonadotropin increased within the normal range, although that of alpha-subunit did not show a significant change. These results suggest that the production of alpha-subunit by tumors may be autonomous in contrast with a regulatory production in the pituitary.

  6. Pharmacokinetics of the Podoviridae phage LH-01 in mice infected with Klebsiella pneumoniae%肺炎克雷伯菌短尾噬菌体LH-01药代动力学研究

    Institute of Scientific and Technical Information of China (English)

    陈松建; 张改; 靳静; 李振江; 王书伟; 李亚辉; 王小亭; 王进; 王中全

    2016-01-01

    目的 探讨噬菌体LH-01在小鼠体内的药代动力学及其影响因素. 方法 观察LH-01在小鼠体内的代谢过程和LH-01中和抗体产生规律.建立小鼠败血症感染模型,使用高剂量和低剂量LH-01进行治疗,观察小鼠健康评分(0~5),同时检测小鼠外周血和主要脏器内活菌数和噬菌体滴度变化规律. 结果 噬菌体LH 01在小鼠体内具有较低的清除率,活性噬菌体可在小鼠体内持续存在数天,10d后完全消失.2周时外周血LH-01中和抗体效价为1∶8,5周时最高为1∶1 024.用高剂量组(1010 PFU/ml)和低价量(104 PFU/ml)的噬菌体LH-01尾静脉注射治疗小鼠败血症,两组组小鼠健康评分最终差异无统计学意义(P>0.05),最终生存率均为100%,而对照组为0%.治疗组小鼠外周血和脏器(肝脏、脾脏和肺脏)中的菌落数显著少于对照组菌落数(P<0.01),尤以脾脏中菌落数减少最显著.LH-01治疗中具有自我放大效应,高剂量和低剂量治疗组小鼠外周血、肝脏和肺脏中的噬菌体滴度与噬菌体对照组相比均显著升高(P<0.01),尤以外周血增加最为明显. 结论 LH-01具有杀菌效率高、自我增殖能力强、活性维持时间长、中和抗体产生晚等良好的药代动力学特性,可试用于多重耐药肺炎克雷伯菌感染的治疗.%Objective To investigate the pharmacokinetics of the phage LH-01 and factors influencing its pharmacokinetics in mice.Methods Changes in the pharmacokinetics of the phage LH-01 were observed in different tissues of mice,and the titer of phage-neutralizing antibodies in serum was also determined.After mice with pneumoniae-induced septicemia were treated with different doses of LH-01 (high and low),the health of those mice was assessed on a scale of 0 to 5 points.The number of phage particles and/or surviving bacterial cells in the organs (PFU/g or CFU/g) and blood (PFU/ml or CFU/ml) were measured.Results Phage LH-01 was still viable in vivo

  7. Research Development and Perspective on Slow Slip, Tremors, and Slow Earthquakes

    Institute of Scientific and Technical Information of China (English)

    Wang Yanzhao; Shen Zhengkang

    2007-01-01

    Seismological and geodetic observations indicate that slow slip sometimes occurs in active fault zones beneath the seismogenic depth, and large slow slip can result in transient ground motion.Slow earthquakes, on the other hand, emit tremor-like signals within a narrow frequency band, and usually produce no catastrophic consequences. In general, slow slip and slow earthquakes probably correspond to deformation processes associated with releasing elastic energy in fault zones, and understanding their mechanisms may help improve our understanding of fault zone dynamic processes. This article reviews the research progress on slow slip and slow earthquakes over the last decade. Crustal motion and tremor activities associated with slow slip and slow earthquakes have been investigated extensively, mainly involving locating sources of slow slip and slow earthquakes and numerical modeling of their processes. In the meantime, debates have continued about slow slip and slow earthquakes,such as their origins, relationship, and mechanisms.

  8. A slow gravity compensated atom laser

    DEFF Research Database (Denmark)

    Kleine Büning, G.; Will, J.; Ertmer, W.

    2010-01-01

    We report on a slow guided atom laser beam outcoupled from a Bose–Einstein condensate of 87Rb atoms in a hybrid trap. The acceleration of the atom laser beam can be controlled by compensating the gravitational acceleration and we reach residual accelerations as low as 0.0027 g. The outcoupling...... mechanism allows for the production of a constant flux of 4.5×106 atoms per second and due to transverse guiding we obtain an upper limit for the mean beam width of 4.6 μm. The transverse velocity spread is only 0.2 mm/s and thus an upper limit for the beam quality parameter is M 2=2.5. We demonstrate...... the potential of the long interrogation times available with this atom laser beam by measuring the trap frequency in a single measurement. The small beam width together with the long evolution and interrogation time makes this atom laser beam a promising tool for continuous interferometric measurements....

  9. Photoperiod influences the central effects of ghrelin on food intake, GH and LH secretion in sheep.

    Science.gov (United States)

    Harrison, Joanne L; Miller, David W; Findlay, Patricia A; Adam, Clare L

    2008-01-01

    Ghrelin is a circulating peptide, primarily secreted by the gut, that has reported actions within the hypothalamo-pituitary axis to stimulate food intake, inhibit GnRH/LH secretion and stimulate GH secretion in monogastric species. Here, we examine responses to centrally administered ghrelin in a seasonal ruminant. Estradiol-implanted castrated male sheep with indwelling intracerebroventricular (i.c.v.) cannulae were kept with unrestricted food for 16 weeks in long day photoperiod (LD, 16 h light/day) then 16 weeks in short days (SD, 8 h light/day). In week 16 of each photoperiod they were given a control (saline) i.c.v. injection on day 1 and ghrelin i.c.v. injection on day 2. Mean circulating endogenous plasma ghrelin concentrations showed no diurnal pattern and were similar between the photoperiods. Central ghrelin injection increased voluntary food intake 2-fold in the first hour after administration in LD but not in SD, decreased LH pulse frequency and amplitude in SD but not in LD, and stimulated GH release in both photoperiods, although there was a 1.5-fold larger response in LD. Therefore, central injection of ghrelin to sheep acutely stimulated food intake in LD, suppressed reproductive neuroendocrine output in SD, and stimulated GH secretion irrespective of photoperiod, although more pronounced in LD. These data indicate that photoperiod can influence hypothalamic appetite and reproductive neuroendocrine responses to ghrelin in seasonal species.

  10. Dependence of the L-H power threshold on magnetic balance and heating method in NSTX

    Science.gov (United States)

    Maingi, R.; Biewer, T.; Meyer, H.; Bell, R.; Leblanc, B.; Chang, C. S.

    2007-11-01

    H-mode access is a critical issue for next step devices, such as the International Thermonuclear Experimental Reactor (ITER), which is projected to have a modest heating power margin over the projected L-H power threshold (PLH). The importance of a second X-point in setting the value of PLH has been clarified in recent experiments on several tokamaks. Specifically a reduction of PLH was observed when the magnetic configuration was changed from single null (SN) to double null (DN) in the MAST, NSTX, and ASDEX-Upgrade devices [1]. Motivated by these results, detailed PLH studies on NSTX have compared discharges with neutral beam and rf heating, as a function of drsep. Similar PLH values and edge parameters are observed with the two heating methods in the same magnetic configuration, with PLH ˜ 0.6 MW lowest in DN and increasing to ˜ 1.1 MW and 2-4 MW in lower-SN and upper-SN configurations respectively (ion grad-B-drift towards lower X-point). The evolution of the experimental profiles of parameters in L-mode before the L/H transition will be compared with simulations using the XGC code (C.S. Chang). [1] MEYER, H. et al., Nucl. Fusion 46 (2006) 64.

  11. X-rays from the location of the Bactrian Transient ASASSN-15lh

    CERN Document Server

    Margutti, R; Chornock, R; Milisavljevic, D; Berger, E; Blanchard, P K; Guidorzi, C; Migliori, G; Kamble, A; Lunnan, R; Nicholl, M; Coppejans, D L; Dall'Osso, S; Drout, M R; Perna, R; Sbarufatti, B

    2016-01-01

    We present the detection of persistent soft X-ray radiation with L_x ~ 10^41-10^42 erg/s at the location of the extremely luminous, double-humped transient ASASSN-15lh as revealed by Chandra and Swift. We interpret this finding in the context of observations from our multiwavelength campaign, which revealed the presence of weak narrow nebular emission features from the host-galaxy nucleus and clear differences with respect to superluminous supernova optical spectra. Significant UV flux variability on short time-scales detected at the time of the re-brightening disfavors the shock interaction scenario as the source of energy powering the long-lived UV emission, while deep radio limits exclude the presence of relativistic jets propagating into a low-density environment. We propose a model where the extreme luminosity and double-peaked temporal structure of ASASSN-15lh is powered by a central source of ionizing radiation that produces a sudden change of the ejecta opacity at later times. As a result, UV radiatio...

  12. The Unusual Super-luminous Supernovae SN 2011kl and ASASSN-15lh

    Science.gov (United States)

    Bersten, Melina C.; Benvenuto, Omar G.; Orellana, Mariana; Nomoto, Ken'ichi

    2016-01-01

    Two recently discovered very luminous supernovae (SNe) present stimulating cases to explore the extents of the available theoretical models. SN 2011kl represents the first detection of a supernova explosion associated with an ultra-long duration gamma-ray burst. ASASSN-15lh was even claimed as the most luminous SN ever discovered, challenging the scenarios so far proposed for stellar explosions. Here we use our radiation hydrodynamics code in order to simulate magnetar-powered SNe. To avoid explicitly assuming neutron star properties, we adopt the magnetar luminosity and spin-down timescale as free parameters of the model. We find that the light curve (LC) of SN 2011kl is consistent with a magnetar power source, as previously proposed, but we note that some amount of 56Ni (≳ 0.08{M}⊙ ) is necessary to explain the low contrast between the LC peak and tail. For the case of ASASSN-15lh, we find physically plausible magnetar parameters that reproduce the overall shape of the LC provided the progenitor mass is relatively large (an ejecta mass of ≈ 6{M}⊙ ). The ejecta hydrodynamics of this event is dominated by the magnetar input, while the effect is more moderate for SN 2011kl. We conclude that a magnetar model may be used for the interpretation of these events and that the hydrodynamical modeling is necessary to derive the properties of powerful magnetars and their progenitors.

  13. The Unusual Super-Luminous Supernovae SN 2011kl and ASASSN-15lh

    CERN Document Server

    Bersten, Melina C; Orellana, Mariana; Nomoto, Ken'ichi

    2016-01-01

    Two recently discovered very luminous supernovae (SNe) present stimulating cases to explore the extents of the available theoretical models. SN 2011kl represents the first detection of a supernova explosion associated with an ultra-long duration gamma ray burst. ASASSN-15lh was even claimed as the most luminous SN ever discovered, challenging the scenarios so far proposed for stellar explosions. Here we use our radiation hydrodynamics code in order to simulate magnetar powered SNe. To avoid explicitly assuming neutron star properties we adopt the magnetar luminosity and spin-down timescale as free parameters of the model. We find that the light curve (LC) of SN 2011kl is consistent with a magnetar power source, as previously proposed, but we note that some amount of 56^Ni (> 0.08 M_sun) is necessary to explain the low contrast between the LC peak and tail. For the case of ASASSN-15lh we find physically plausible magnetar parameters that reproduce the overall shape of the LC provided the progenitor mass is rel...

  14. Impact of Resonant Magnetic Perturbations on the L-H Transition on MAST

    CERN Document Server

    Scannell, R; Carr, M; Hawke, J; Henderson, S S; O'Gorman, T; Patel, A; Shaw, A; Thornton, A

    2014-01-01

    The impact of resonant magnetic perturbations (RMPs) on the power required to access H-mode is examined experimentally on MAST. Applying RMP in n=2,3,4 and 6 configurations causes significant delays to the timing of the L-H transition at low applied fields and prevents the transition at high fields. The experiment was primarily performed at RMP fields sufficient to cause moderate increases in ELM frequency, f mitigated/f natural~3. To obtain H-mode with RMPs at this field, an increase of injected beam power is required of at least 50% for n=3 and n=4 RMP and 100% for n=6 RMP. In terms of power threshold, this corresponds to increases of at least 20% for n=3 and n=4 RMPs and 60% for n=6 RMPs. This 'RMP affected' power threshold is found to increase with RMP magnitude above a certain minimum perturbed field, below which there is no impact on the power threshold. Extrapolations from these results indicate large increases in the L-H power threshold will be required for discharges requiring large mitigated ELM fre...

  15. Leptin regulation of inward membrane currents, electrical activity and LH release in isolated bovine gonadotropes.

    Science.gov (United States)

    Domínguez-Mancera, Belisario; Barrientos-Morales, Manuel; Cervantes-Acosta, Patricia; Hernández-Beltrán, Antonio; Rodríguez-Andrade, Araceli; González-Ramírez, Ricardo; Monjaraz, Eduardo; Felix, Ricardo

    2017-09-09

    Leptin, a peptide hormone produced by adipocytes, is recognized as one of the signals involved in the onset of reproductive activity. The leptin receptor has been found in hypothalamic neurons and pituitary gonadotropes, suggesting that the hormone may act at both sites to stimulate the secretion of GnRH and consequently, FSH and LH. In response to a stimulus such as a hypothalamic secretagogue, gonadotropes respond with changes in electrical activity, intracellular Ca(2+) and hormone release. The main aim of this report was to investigate whether leptin promotes a change in the electrical and secretory activities of bovine gonadotropes. After 48 h of treatment with leptin (10 nM) significant changes in the action potential properties were observed in gonadotropes, which included an increase in amplitude, time-to-pike and post-hyperpolarization, as well as a decrease in firing threshold. Likewise, leptin induced a significant (∼1.3-fold) up-regulation of voltage-gated Na(+) channel current density, and a selective increase (∼2.1-fold) in Ca(2+) current density through high voltage-activated channels. Consistent with this, leptin enhanced GnRH-induced secretion of LH measured by ELISA. We suggest that leptin enhances membrane expression of voltage-gated Na(+) and Ca(2+) channels, which results in a modulation of the action potential properties and an increase in hormone release from gonadotropes. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Effect of ovine luteinizing hormone (oLH) charge isoforms on VEGF and cAMP production.

    Science.gov (United States)

    Montero-Pardo, Arnulfo; Diaz, Daniel; Olivares, Aleida; González-Padilla, Everardo; Murcia, Clara; Gómez-Chavarín, Margarita; Gutiérrez-Ospina, Gabriel; Perera-Marín, Gerardo

    2015-12-01

    Although an increase in VEGF expression and synthesis in association with LH has been established; it is unknown if all LH isoforms act similarly. This study evaluated the production of cAMP and VEGF among LH isoforms in two in vitro bioassays. The LH was obtained from hypophyses and the group of isoforms was isolated by chromatofocusing. cAMP production was assessed using the in vitro bioassay of HEK-293 cells and VEGF production was evaluated in granulosa cells. Immunological activity was measured with a homologous RIA. Immunoactivity and bioactivity for each isoform were compared against a standard, by estimating the IC50 and the EC50. The basic isoforms were more immunoactive than the standard. The neutral and the moderately acidic had an immunological activity similar to the standard. The acidic isoform was the least immunoreactive. cAMP production at the EC50 dose was similar among the basic isoforms, the moderately acidic and the standard; for the neutral and the acidic, the EC50 dose was higher. It was observed that compared with the control, VEGF production at the lowest LH dose was no different in the standard and each isoform. In the intermediate dose, a positive response was caused in the standard and the neutral and basic isoforms. Although the acidic isoform showed a dose-dependent response, it was not significant relative to the control. In conclusion, the basic isoform generated the greatest cAMP and VEGF production, similar to the reference standard, and the acidic the smallest.

  17. Spectral heterogeneity and carotenoid-to-bacteriochlorophyll energy transfer in LH2 light-harvesting complexes from Allochromatium vinosum.

    Science.gov (United States)

    Magdaong, Nikki M; LaFountain, Amy M; Hacking, Kirsty; Niedzwiedzki, Dariusz M; Gibson, George N; Cogdell, Richard J; Frank, Harry A

    2016-02-01

    Photosynthetic organisms produce a vast array of spectral forms of antenna pigment-protein complexes to harvest solar energy and also to adapt to growth under the variable environmental conditions of light intensity, temperature, and nutrient availability. This behavior is exemplified by Allochromatium (Alc.) vinosum, a photosynthetic purple sulfur bacterium that produces different types of LH2 light-harvesting complexes in response to variations in growth conditions. In the present work, three different spectral forms of LH2 from Alc. vinosum, B800-820, B800-840, and B800-850, were isolated, purified, and examined using steady-state absorption and fluorescence spectroscopy, and ultrafast time-resolved absorption spectroscopy. The pigment composition of the LH2 complexes was analyzed by high-performance liquid chromatography, and all were found to contain five carotenoids: lycopene, anhydrorhodovibrin, spirilloxanthin, rhodopin, and rhodovibrin. Spectral reconstructions of the absorption and fluorescence excitation spectra based on the pigment composition revealed significantly more spectral heterogeneity in these systems compared to LH2 complexes isolated from other species of purple bacteria. The data also revealed the individual carotenoid-to-bacteriochlorophyll energy transfer efficiencies which were correlated with the kinetic data from the ultrafast transient absorption spectroscopic experiments. This series of LH2 complexes allows a systematic exploration of the factors that determine the spectral properties of the bound pigments and control the rate and efficiency of carotenoid-to-bacteriochlorophyll energy transfer.

  18. Effect of epinephrine, norepinephrine and(or) GnRH on serum LH in prepuberal beef heifers.

    Science.gov (United States)

    Hardin, D R; Randel, R D

    1983-09-01

    Forty prepuberal Simmental X Brahman-Hereford heifers were utilized to determine the effects of epinephrine (E), norepinephrine (NE), gonadotropin releasing hormone (GnRH) or combinations of GnRH + E and GnRH + NE on serum luteinizing hormone (LH) concentrations. Animals were assigned randomly to one of five treatments with four replicates/treatment. Treatments consisted of I) 100 micrograms GnRH at time 0 (n = 8); II) 50 mg NE at time -15 and 0 (n = 8); III) 50 mg E at time -15 and 0 (n = 8); IV) 100 micrograms GnRH at time 0, plus 50 mg NE at time -15 and 0 (n = 8) and V) 100 micrograms GnRH at time 0, plus 50 mg E at time -15 and 0 (n = 8). All treatment compounds were administered im in 2 ml physiological saline and blood samples were collected via tail vessel puncture at -30, -15, 0, 15, 30, 45, 60, 90, 120, 180, 240, 300 and 360 min from GnRH injection. Treatment with NE or E alone had no effect (P greater than .10) on serum LH during the sampling period. The initial LH release to GnRH was altered (P less than .05) by concomitant treatment with NE (treatment IV) or E (treatment V). Magnitude of the LH release was reduced (P less than .01) by treatment V. Area under the LH surge was reduced (P less than .05) by treatment IV (NE) and V (E).

  19. The effect of nutrition on the neural mechanisms potentially involved in melatonin-stimulated LH secretion in female Mediterranean goats.

    Science.gov (United States)

    Zarazaga, Luis A; Celi, Irma; Guzmán, José Luis; Malpaux, Benoît

    2011-12-01

    This research examines which neural mechanisms among the endogenous opioid, dopaminergic, serotonergic and excitatory amino acid systems are involved in the stimulation of LH secretion by melatonin implantation and their modulation by nutritional level. Female goats were distributed to two experimental groups that received either 1.1 (group H; n=24) or 0.7 (group L; n=24) times their nutritional maintenance requirements. Half of each group was implanted with melatonin after a long-day period. Plasma LH concentrations were measured twice per week. The effects of i.v. injections of naloxone, pimozide, cyproheptadine and N-methyl-d,l-aspartate (NMDA) on LH secretion were assessed the day before melatonin implantation and again on days 30 and 45. The functioning of all but the dopaminergic systems was clearly modified by the level of nutrition, melatonin implantation and time elapsed since implantation. Thirty days after implantation, naloxone increased LH concentrations irrespective of the level of nutrition (Pgoats (HM; Pnutritional level and melatonin implantation. Endogenous opioids seem to be most strongly involved in the inhibition of LH secretion on days 30 and 45 after melatonin implantation. However, the serotonergic mechanism appears to be most influenced by nutritional level.

  20. Differential effects of the persistent DDT metabolite methylsulfonyl-DDE in nonstimulated and LH-stimulated neonatal porcine Leydig cells.

    Science.gov (United States)

    Castellanos, Cesilie Granum; Sørvik, Irene Beate; Tanum, Marte Bruu; Verhaegen, Steven; Brandt, Ingvar; Ropstad, Erik

    2013-03-15

    3-Methylsulfonyl-DDE (MeSO₂-DDE) is a potent adrenal toxicant formed from the persistent insecticide DDT. MeSO₂-DDE is widely present in human plasma, milk and fat, and in tissues of marine mammals. In the present study, we investigated endocrine-disrupting properties of MeSO₂-DDE in primary neonatal porcine Leydig cells. Unstimulated and LH-stimulated cells were exposed to MeSO₂-DDE at concentrations ranging from 0.6 to 20 μM for 48 h. Cell viability, hormone secretion and expression of steroidogenesis related genes were recorded. Secretion of testosterone and estradiol was increased in a concentration-dependent fashion in unstimulated Leydig cells, while in LH-stimulated cells, secretion of testosterone, estradiol and progesterone was decreased. The expression of important steroidogenic genes was down-regulated both in unstimulated and LH-stimulated cells. Notably, no significant impairment of cell viability occurred at any exposure except the highest concentration (20 μM) in LH-stimulated cells. This indicated that the effects on hormone secretion and gene expression were not caused by cytotoxicity. We conclude that the adrenal toxicant MeSO₂-DDE disrupts hormone secretion in a complex fashion in neonatal porcine Leydig cells. The different endocrine responses in unstimulated and LH-stimulated cells imply that the endocrine disruptive activity of MeSO₂-DDE is determined by the physiological status of the Leydig cells.

  1. Investigation of lower hybrid current drive during H-mode in EAST tokamak

    Institute of Scientific and Technical Information of China (English)

    Li Miao-Hui; Liu Fu-Kun; Wang Mao; Xu Han-Dong; Wan Bao-Nian; Ding Bo-Jiang; Kong Er-Hua; Zhang Lei; Zhang Xin-Jun; Qian Jin-Ping; Yan Ning; Han Xiao-Feng; Shan Jia-Fang

    2011-01-01

    H-mode discharges with lower hybrid current drive (LHCD) alone are achieved in EAST divertor plasma over a wide parameter range.These H-mode discharges are characterized by a sudden drop in Dα emission and a spontaneous rise in main plasma density.Good lower hybrid (LH) coupling during H-mode is obtained by putting the plasma close to the antenna and by injecting D2 gas from a pipe near the grill mouse.The analysis of lower hybrid current drive properties shows that the LH deposition profile shifts off axis during H-mode,and current drive (CD) efficiency decreases due to the increase in density.Modeling results of H-mode discharges with a general ray tracing code GENRAY are reported.

  2. Lower Hybrid Current Drive in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Ekedahl, A.; Goniche, M.; Guilhem, D.; Kazarian, F.; Peysson, Y. and Tore Supra Team [CEA, IRFM, F-13108 St Paul Les Durance, (France)

    2009-07-01

    Since the mission of Tore Supra is to produce quasi-steady-state discharges, the lower hybrid current drive (LHCD) system constitutes the most important method of additional hewing and noninductive current drive. A description of the LHCD is given, including the different launcher designs developed for the Tore Supra long-pulse program. Following the completion of the Composants Internes et Limiteur project, together with the installation of a high-performance LHCD launcher, world record discharges, injected and extracted energy exceeding 1 GJ, were obtained in 2003. With the flexibility of lower hybrid (LH) waves to tailor the current profile, an enhanced performance regime, the so-called LHEP has been maintained in quasi-steady-state discharges. Detailed measurements of the fast electron distribution have allowed us to constrain LHCD ray-tracing models and to quantify parametric dependencies describing the fast electron tail. Localized heat loads oil the LHCD launchers due to interaction with fast particles have been measured and quantified, using infrared imaging and calorimetric measurements oil water-cooled plasma facing components. Furthermore, experimental results in the area of LH wave coupling are presented. (authors)

  3. Singlet-triplet fission of carotenoid excitation in light-harvesting LH2 complexes of purple phototrophic bacteria.

    Science.gov (United States)

    Klenina, I B; Makhneva, Z K; Moskalenko, A A; Gudkov, N D; Bolshakov, M A; Pavlova, E A; Proskuryakov, I I

    2014-03-01

    The current generally accepted structure of light-harvesting LH2 complexes from purple phototrophic bacteria conflicts with the observation of singlet-triplet carotenoid excitation fission in these complexes. In LH2 complexes from the purple bacterium Allochromatium minutissimum, a drop in the efficiency of carotenoid triplet generation is demonstrated, which correlates with the extent of selective photooxidation of bacteriochlorophylls absorbing at ~850 nm. We conclude that singlet-triplet fission of carotenoid excitation proceeds with participation of these excitonically coupled bacteriochlorophylls. In the framework of the proposed mechanism, the contradiction between LH2 structure and photophysical properties of carotenoids is eliminated. The possibility of singlet-triplet excitation fission involving a third mediator molecule was not considered earlier.

  4. Lower hybrid heating and current drive in ignitor shear reversal scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Barbato, E.; Pinaccione, L. [Italian Agengy for New Technologies, Energy and the Environment, Centro Ricerche Frascati, Rome (Italy). Dip. Energia

    1996-05-01

    Injection of Lower Hybrid (LH) Wave power at 8 GHz is considered into IGNITOR shear reversal scenarios, characterized by a reduced plasma current and density. Power deposition calculation are performed to establish whether LH waves can be used both as central heating and off axis current drive tool. It turns out that LH waves can be used (a) for central plasma heating purpose during the current vamp phase, to freeze the shear reversed configuration, at the power level of {approx}10 MW. (b) to drive a current in the outer part of the plasma at the power level of 20 MW. In this way around 1/3-1/6 of the total current in the proper plasma position (i.e. where q is minimum) is driven.

  5. Inherited ataxia with slow saccades

    Directory of Open Access Journals (Sweden)

    R T Chakor

    2012-01-01

    Full Text Available Ataxia is a symptom of cerebellar dysfunction. Slowly progressive ataxia, dysarthria in an adult with a positive family history suggests an inherited cerebellar ataxia. We present an adult with gradually progressive ataxia and slow saccades. There was history of similar illness in his son. Genetic testing for spinocerebellar ataxia 2 was positive. We discuss the various inherited ataxias, causes of acute, progressive ataxia syndromes, episodic ataxias and ataxia associated with other neurological signs like peripheral neuropathy, pyramidal features, movement disorders and cognitive decline.

  6. Can Occupational Therapy Slow Alzheimer's Decline?

    Science.gov (United States)

    ... news/fullstory_162135.html Can Occupational Therapy Slow Alzheimer's Decline? Patients, caregivers may reap some benefits, but ... slow down the physical decline that comes with Alzheimer's disease, a new clinical trial suggests. The study ...

  7. Plasma and ovarian oestradiol and the variability in the LH surge induced in ewes by the ram effect.

    Science.gov (United States)

    Fabre-Nys, Claude; Chanvallon, Audrey; Debus, Nathalie; François, Dominique; Bouvier, Frédéric; Dupont, Joelle; Lardic, Lionel; Lomet, Didier; Ramé, Christelle; Scaramuzzi, Rex J

    2015-05-01

    The proportion of anoestrous ewes ovulating after exposure to a sexually active ram is variable mainly due to whether an LH surge is induced. The aim of this study was to determine the role of oestradiol (E2) in the ram-induced LH surge. In one study, we measured the plasma concentrations of E2 in ewes of different breeds before and after the 'ram effect' and related these patterns to the presence and latency of the LH surge, while another compared ovarian responses with the 'ram effect' following exposure to rams for 2 or 12 h. In all ewes, the concentration of E2 increased 2-4 h after rams were introduced and remained elevated for 14.5 ± 0.86 h. The quantity of E2 secreted before the LH surge varied among breeds as did the mean concentration of E2. The granulosa cells of IF ewes collected after 12 h exposure to rams secreted more E2 and progesterone and had higher levels of StAR than the 2 h group but in MV ewes there was no differences between these groups for any of these parameters. These results demonstrate that the LH surge induced by the rams is a result of increased E2 secretion associated with increased levels of STAR in granulosa cells and that these responses varied among breeds. The results suggest that the variable occurrence of a LH surge and ovulation may be the result of variable ovarian responses to the 'ram effect' and insensitivity of the hypothalamus to the E2-positive feedback signal.

  8. The influence of season of lambing and lactation on reproductive activity and plasma LH concentrations in Merino ewes.

    Science.gov (United States)

    Restall, B J; Starr, B G

    1977-03-01

    Groups of Merino ewes which were lactating for 40 days (Group I) or had had their lambs removed at birth (Group II) after lambing in the winter (June) or spring (November) were fed on a high plane of nutrition. Ovarian inspections were carried out at 15 and 30 days after lambing and plasma LH levels were measured at 6-h intervals for 20-30 days. First ovulation was earlier in ewes lambing in the winter (16-6 days, range 11-26) than in the spring (24-7 days, range 15-30) but there was no difference in the number of ewes ovulating. LH levels were higher in winter-lambing ewes (2-79 +/- 3-4 ng/ml) than in those lambing in the spring (1-78 +/- 0-23 ng/ml). LH peaks were usually associated with an ovulation in spring lambing ewes but were not consistently so in the others. More ewes ovulated in Group II (72%) than in Group I (40%) but the mean time of first ovulation was similar. In the winter-lambing ewes the mean daily LH concentration was 2-40 +/- 0-32 ng/ml in Group I and 3-18 +/- 0-31 ng/ml in Group II but there were no differences between the spring-lambing ewes, (I, 1-75 +/- 0-20 ng/ml; II, 1-80 +/- 0-26 ng/ml). There were more elevations in LH levels in Group II ewes (64%) than in Group I ewes (43-8%). After lambing the LH levels increased slowly, indicating a gradual recovery of pituitary function.

  9. Developmental Programming: Insulin Sensitizer Prevents the GnRH-Stimulated LH Hypersecretion in a Sheep Model of PCOS.

    Science.gov (United States)

    Cardoso, Rodolfo C; Burns, Ashleigh; Moeller, Jacob; Skinner, Donal C; Padmanabhan, Vasantha

    2016-12-01

    Prenatal testosterone (T) treatment recapitulates the reproductive and metabolic phenotypes of polycystic ovary syndrome in female sheep. At the neuroendocrine level, prenatal T treatment results in disrupted steroid feedback on gonadotropin release, increased pituitary sensitivity to GnRH, and subsequent LH hypersecretion. Because prenatal T-treated sheep manifest functional hyperandrogenism and hyperinsulinemia, gonadal steroids and/or insulin may play a role in programming and/or maintaining these neuroendocrine defects. Here, we investigated the effects of prenatal and postnatal treatments with an androgen antagonist (flutamide [F]) or an insulin sensitizer (rosiglitazone [R]) on GnRH-stimulated LH secretion in prenatal T-treated sheep. As expected, prenatal T treatment increased the pituitary responsiveness to GnRH leading to LH hypersecretion. Neither prenatal interventions nor postnatal F treatment normalized the GnRH-stimulated LH secretion. Conversely, postnatal R treatment completely normalized the GnRH-stimulated LH secretion. At the tissue level, gestational T increased pituitary LHβ, androgen receptor, and insulin receptor-β, whereas it reduced estrogen receptor (ER)α protein levels. Although postnatal F normalized pituitary androgen receptor and insulin receptor-β, it failed to prevent an increase in LHβ expression. Contrarily, postnatal R treatment restored ERα and partially normalized LHβ pituitary levels. Immunohistochemical findings confirmed changes in pituitary ERα expression to be specific to gonadotropes. In conclusion, these findings indicate that increased pituitary responsiveness to GnRH in prenatal T-treated sheep is likely a function of reduced peripheral insulin sensitivity. Moreover, results suggest that restoration of ERα levels in the pituitary may be one mechanism by which R prevents GnRH-stimulated LH hypersecretion in this sheep model of polycystic ovary syndrome-like phenotype.

  10. Integrated Photonics Enabled by Slow Light

    DEFF Research Database (Denmark)

    Mørk, Jesper; Chen, Yuntian; Ek, Sara;

    2012-01-01

    In this talk we will discuss the physics of slow light in semiconductor materials and in particular the possibilities offered for integrated photonics. This includes ultra-compact slow light enabled optical amplifiers, lasers and pulse sources.......In this talk we will discuss the physics of slow light in semiconductor materials and in particular the possibilities offered for integrated photonics. This includes ultra-compact slow light enabled optical amplifiers, lasers and pulse sources....

  11. Spectroscopic studies of two spectral variants of light-harvesting complex 2 (LH2) from the photosynthetic purple sulfur bacterium Allochromatium vinosum

    National Research Council Canada - National Science Library

    Niedzwiedzki, Dariusz M; Bina, David; Picken, Nichola; Honkanen, Suvi; Blankenship, Robert E; Holten, Dewey; Cogdell, Richard J

    2012-01-01

    Two spectral forms of the peripheral light-harvesting complex (LH2) from the purple sulfur photosynthetic bacterium Allochromatium vinosum were purified and their photophysical properties characterized...

  12. Recombinant LH supplementation to recombinant FSH during the final days of controlled ovarian stimulation for in vitro fertilization. A multicentre, prospective, randomized, controlled trial

    DEFF Research Database (Denmark)

    Nyboeandersen, A; Al Humaidan, Peter Samir Heskjær; Fried, G

    2008-01-01

    either rFSH (Gonal-F) alone (n = 261) or to continue after Day 6 of stimulation with both rFSH (Gonal-F) and rLH (Luveris) (n = 265) from Day 6. The starting dose of rFSH was 150-225 IU/day according to age below or above 35 years. RESULTS: Ongoing pregnancy rate at week 10-12 was 28.7% after rFSH alone...... and 27.2% after rFSH + rLH. This showed no evidence of a difference. Administration of rLH significantly (P....9% low Day 1 LH; 22.1% low Day 6 LH) versus rFSH + rLH (25.0% low Day 1 LH; 28.9% low Day 6 LH). CONCLUSIONS: Supplementing rFSH with daily doses of 75-150 IU of rLH during the second half of the follicular phase showed no evidence of increasing the ongoing pregnancy rates in the general population...

  13. Plasma transport properties at the L-H transition and high performance phase of JET discharges

    Energy Technology Data Exchange (ETDEWEB)

    Balet, B.; Cordey, J.G.; Erba, M.; Jones, T.T.C.; Lomas, P.J.; Smeulders, P.; Springmann, E.M.; Stubberfield, P.M.; Taroni, A.; Thomsen, K. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Parail, V.V. [Kurchatov Institute, Moscow (Russian Federation)

    1994-07-01

    Numerical analysis are performed which show that both electron and ion thermal diffusivities are reduced by one order of magnitude everywhere, not only in a narrow region near separatrix during the L-H transition. There is no separate H-VH transition on JET, this transition coincides with the cessation of ELMs. In the ELM free phase ion transport in the core is close to its neoclassical value, but probably rises towards plasma edge (however still remaining much less than it was in L-mode). The best agreement with experiment is obtained with the model which simultaneously takes into account both the global reduction of Bohm type anomalous transport in plasma core and formation of temperature pedestal near plasma edge. (authors). 6 refs., 5 figs.

  14. Locality effects on bifurcation paradigm of L-H transition in tokamak plasmas

    Directory of Open Access Journals (Sweden)

    Boonyarit Chatthong

    2015-12-01

    Full Text Available The locality effects on bifurcation paradigm of L-H transition phenomenon in magnetic confinement plasmas are investigated. One dimensional thermal transport equation with both neoclassical and anomalous transports effects included is considered, where a flow shear due to pressure gradient component is included as a transport suppression mechanism. Three different locally driven models for anomalous transport are considered, including a constant transport model, pressure gradient driven transport model, and critical pressure gradient threshold transport model. Local stability analysis shows that the transition occurs at a threshold flux with hysteresis nature only if ratio of anomalous strength over neoclassical transport exceeds a critical value. The depth of the hysteresis loop depends on both neoclassical and anomalous transports, as well as the suppression strength. The reduction of the heat flux required to maintain H-mode can be as low as a factor of two, which is similar to experimental evidence.

  15. NSTX ELM Pacing and L-H Threshold Experiments for ITER

    Science.gov (United States)

    Canik, J. M.; Maingi, R.; Sontag, A. C.; Gerhardt, S. P.; Kaye, S.; Bell, R. E.; Gates, D.; Goldston, R.; Leblanc, B. P.; Menard, J.; Park, J.-K.; Evans, T.; Osborne, T.; Sabbagh, S.; Unterberg, E. A.

    2009-11-01

    We present a summary of recent edge-localized mode (ELM) pacing and L-H power threshold (PLH) experiments performed in NSTX in support of ITER. ELM triggering using 3D magnetic perturbations was used to perform pacing during ELM-free H-modes induced by lithium conditioning, mitigating the impurity accumulation typically observed in these conditions. The waveform of the applied field has been tailored to provide high reliability triggering at frequencies of >60 Hz to reduce the average ELM size. ELM pacing was also performed using vertical position oscillations, with the ELM frequency increased to ˜30 Hz from a natural frequency of ˜15 Hz. PLH is reduced by ˜50% at low triangularity, and also decreased by ˜50% during discharge with thick lithium wall coatings. PLH was observed to increase strongly with plasma current during sustained H-modes. The influence of heating method, non-axisymmetric fields, and magnetic balance on PLH will be presented.

  16. Multilayer-MCTDH approach to the energy transfer dynamics in the LH2 antenna complex

    Science.gov (United States)

    Shibl, Mohamed F.; Schulze, Jan; Al-Marri, Mohammed J.; Kühn, Oliver

    2017-09-01

    The multilayer multiconfiguration time-dependent Hartree method is used to study the coupled exciton-vibrational dynamics in a high-dimensional nonameric model of the LH2 antenna complex of purple bacteria. The exciton-vibrational coupling is parametrized within the Huang-Rhys model according to phonon and intramolecular vibrational modes derived from an experimental bacteriochlorophyll spectral density. In contrast to reduced density matrix approaches, the Schrödinger equation is solved explicitly, giving access to the full wave function. This facilitates an unbiased analysis in terms of the coupled dynamics of excitonic and vibrational degrees of freedom. For the present system, we identify spectator modes for the B800 to B800 transfer and we find a non-additive effect of phonon and intramolecular vibrational modes on the B800 to B850 exciton transfer.

  17. Statistical theory of L-H transition and its implication to threshold database

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Sanae-I. [Kyushu Univ., Research Institute for Applied Mechanics, Kasuga, Fukuoka (Japan); Itoh, Kimitaka; Toda, Shinichiro [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2003-01-01

    A statistical model for the bifurcation of the radial electric field E{sub r} is analyzed in view of describing L-H transitions of toroidal plasmas. Noise in micro fluctuations is shown to lead to random changes of E{sub r}, if a deterministic approach allows for more than one solution. The probability density function for and the ensemble average of E{sub r} are obtained. The L-to-H and the H-to-L transition probabilities are calculated, and the effective phase limit is derived. Due to the suppression of turbulence by shear in E{sub r}, the limit deviates from Maxwell's rule. (author)

  18. A theory of lead-time in probabilistic excitation of L/H transition

    Energy Technology Data Exchange (ETDEWEB)

    Toda, Shinichiro; Itoh, Sanae-I.; Yagi, Masatoshi [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan); Fukuyama, Atsushi [Kyoto Univ. (Japan). Dept. of Nuclear Engineering

    2000-07-01

    A quantity of a lead-time, t{sub lead}, is newly introduced to examine the probabilistic occurrence of the L/H transition. The lead-time is a time period during which a transition is likely to occur. We show that the lead-time has the statistical distribution as a function of the distance from critical parameter, e.g.|n{sub c} - n{sub c0}|when the density is a key parameter for transition. It has the dependence like t{sub lead} {proportional_to}|n{sub c} - n{sub c0}|{sup 2} if the background noise distribution is given as P (n{sub c}) {proportional_to}|n{sub c} - n{sub c0}|{sup -2}. (author)

  19. Slowing Down in Chemical Tristability Systems

    Institute of Scientific and Technical Information of China (English)

    ZHAN,Ye-Hong(詹业宏); ZHANG,Chun-Hua(张春华); WU,Fu-Gen(吴福根); HU,Yi-Hua(胡义华)

    2001-01-01

    In this paper two kinds of slowing down in the chamical tristability systems are studied. One is the critical slowing down at the edges of tristable reion, and the other is the slowing down far from the critical point, which has much to do with the unstable steady-points. The results possess some universal propererties.

  20. Slow Monitoring Systems for CUORE

    Science.gov (United States)

    Dutta, Suryabrata; Cuore Collaboration

    2016-09-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale neutrinoless double-beta decay experiment under construction at the Laboratori Nazionali del Gran Sasso (LNGS). The experiment is comprised of 988 TeO2 bolometric crystals arranged into 19 towers and operated at a temperature of 10 mK. We have developed slow monitoring systems to monitor the cryostat during detector installation, commissioning, data taking, and other crucial phases of the experiment. Our systems use responsive LabVIEW virtual instruments and video streams of the cryostat. We built a website using the Angular, Bootstrap, and MongoDB frameworks to display this data in real-time. The website can also display archival data and send alarms. I will present how we constructed these slow monitoring systems to be robust, accurate, and secure, while maintaining reliable access for the entire collaboration from any platform in order to ensure efficient communications and fast diagnoses of all CUORE systems.

  1. Comparative studies on testicular and epididymal morphology, and serum hormone concentrations in foxes and the hybrids during the breeding season.

    Science.gov (United States)

    Yang, T A; Yang, Y H; Peng, Y H; Cong, B; Diao, Y F; Bao, K; Hu, P F; Song, X C; Liu, L L; Yang, Y F; Xing, X M; Yang, F H

    2016-05-01

    The silver fox and the blue fox belong to different genera, and the hybrid males are fully or partially sterile. In the present study, the objective was to evaluate the causes of hybrid male sterility, and therefore analyze the differences in testicular, and epididymal morphology and serum hormone concentrations among silver foxes, blue foxes, and the hybrids during the breeding season. Samples were collected from 20 male silver foxes, 20 male blue foxes, 15 male HSBs (silver fox female × blue fox male hybrids) and 14 male HBSs (blue fox male × silver fox female hybrids), respectively. Seminal evaluation showed large numbers of sperm present in the semen of blue foxes and silver foxes, but no sperm present in the hybrids. Mean testicular volume and the diameter of seminiferous tubules in silver foxes and blue foxes were greater than in the hybrids; and there were many Sertoli cells, spermatogenic cells, and sperm in silver foxes and blue foxes, while spermatogenic cells decreased with no sperm in the hybrids. Mean serum LH and prolactin concentrations in silver foxes and blue foxes were less and testosterone was greater than in the hybrids (P<0.05). The results indicate that germ cell meioses in the hybrids were arrested at the prophase stage of meiosis, and that lesser concentrations of testosterone and greater concentrations of LH and prolactin can inhibit the completion of spermatogenesis.

  2. Blockade of LH release and ovulation in the rabbit with inhibitory analogues of luteinizing hormone releasing hormone.

    Science.gov (United States)

    Phelps, C P; Coy, D H; Schally, A V; Sawyer, C H

    1977-06-01

    Plasma LH levels and ovulation were studied in female rabbits following administration of several inhibitory analogues of luteinizing hormone-releasing hormone (LHRH) before and after mating with experienced males. Administration of (D-Phe2, D-Leu6)-LHRH (1.5 mg/kg sc) to does 30 min before mating did not prevent either LH release or ovulation. However, a single sc injection of (D-Phe2, L-Phe3, D-Phe6y-LHRH (6 mg/kg) given 30 min before mating in 4 rabbits resulted in a 30-60 min delay in the coitus-induced release of LH when compared with post-coital changes in the same animals injected with vehicle; however, all of the does ovulated. When multiple dosages of 4 mg/kg (D-Phe2, L-Phe3, D-Phe6)-LHRH were administered 3-5 times at half-hourly intervals beginning 30 min prior to mating there was a considerable reduction in plasma LH elevations at 0.5, 1.0, 2.0 and 4.0 h after mating and 3/5 treated rabbits showed partial or complete blockade of ovulation. Quite similar results were obtained with the same dosage of (D-Phe2, D-Trp3, D-Phe6)-LHRH. An early sharp peak in LH release and full ovulation were stimulated in 6 out of 6 does by a single iv injection of synthetic LHRH (500 ng/kg). However, in another experiment, three half-hourly sc injections (4 mg/kg) of (D-Phe2, L-Phe3, D-Phe6)-LHRH beginning 30 min before administering LHRH markedly reduced the rise in plasma LH (P less than 0.01) and completely blocked ovulation in all of the same 6 animals. An unsuccessful attempt was made to provide a test animal for LHRH analogue investigations by implanting 4 cm of silastic tubing filled with crystalline estradiol (E2) sc in ovariectomized (OVX) AND INTACT DOES. In OVX does the silastic E2 implants resulted in a progressive decline in the ability to release LH in response to mating at 6 and at 20 days after implantation. With ovaries present, the E2 implant permitted post-coital LH release and ovulation at 4 d but not at 30 d post-implantation. At 30 d after removal of

  3. Density convection near radiating ICRF antennas and its effect on the coupling of lower hybrid waves

    Energy Technology Data Exchange (ETDEWEB)

    Ekedahl, A.; Colas, L.; Beaumont, B.; Bibet, Ph.; Bremond, S.; Kazarian, F. [Association Euratom-CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Mayoral, M.L.; Mailloux, J. [Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX (United Kingdom); Noterdaeme, J.M. [Max-Planck-Institut fuer Plasmaphysik, Euratom Association, Garching (Germany)]|[Gent University, EESA Dept. (Belgium); Tuccillo, A.A. [Associazione Euratom-ENEA sulla Fusione, CR Frascati, Rome (Italy)

    2003-07-01

    Combined operation of lower hybrid (LH) and Ion Cyclotron Resonance Frequency (ICRF) waves can result in a degradation of the LH wave coupling, as observed both in the Tore-Supra and Jet tokamaks. The reflection coefficient on the part of the LH launcher magnetically connected to the powered ICRF antenna increases, suggesting a local decrease in the electron density in the connecting flux tubes. This has been confirmed by Langmuir probe measurements on the LH launchers in the latest Tore-Supra experiments. Moreover, recent experiments in Jet indicate that the LH coupling degradation depends on the ICRF power and its launched k{sub /} spectrum. The 2D density distribution around the Tore-Supra ICRF antennas has been modelled with the CELLS-code, balancing parallel losses with diffusive transport and sheath induced ExB convection, obtained from RF field mapping using the ICANT-code. The calculations are in qualitative agreement with the experimental observations, i.e. density depletion is obtained, localised mainly in the antenna shadow, and dependent on ICRF power and antenna spectrum. (authors)

  4. Lower hybrid current drive experiments on Alcator C-Mod: Comparison with theory and simulationa)

    Science.gov (United States)

    Bonoli, P. T.; Ko, J.; Parker, R.; Schmidt, A. E.; Wallace, G.; Wright, J. C.; Fiore, C. L.; Hubbard, A. E.; Irby, J.; Marmar, E.; Porkolab, M.; Terry, D.; Wolfe, S. M.; Wukitch, S. J.; Alcator C-Mod Team; Wilson, J. R.; Scott, S.; Valeo, E.; Phillips, C. K.; Harvey, R. W.

    2008-05-01

    Lower hybrid (LH) current drive experiments have been carried out on the Alcator C-Mod tokamak [I. H. Hutchinson et al., Phys. Plasmas 1, 1511 (1994)] using a radio-frequency system at 4.6GHz. Up to 900kW of LH power has been coupled and driven LH currents have been inferred from magnetic measurements by extrapolating to zero loop voltage, yielding an efficiency of neILHR0/PLH≈2.5±0.2×1019(A/W/m2). We have simulated the LH current drive in these discharges using the combined ray tracing/three-dimensional (r,v⊥,v∥) Fokker-Planck code GENRAY-CQL3D (R. W. Harvey and M. McCoy, in Proceedings of the IAEA Technical Committee Meeting on Simulation and Modeling of Thermonuclear Plasmas, Montreal, Canada, 1992) and found similar current drive efficiencies. The simulated profiles of current density from CQL3D, including both ohmic plus LH drive have been found to be in good agreement with the measured current density from a motional Stark effect diagnostic. Measurements of nonthermal x-ray emission confirm the presence of a significant fast electron population and the three-dimensional (r,v⊥,v∥) electron distribution function from CQL3D has been used in a synthetic diagnostic code to simulate the measured hard x-ray data.

  5. Diagnostic Value of LH/FSH Ratio on Polycystic Ovary Syndrome%LH/FSH比值对多囊卵巢综合征的诊断价值分析

    Institute of Scientific and Technical Information of China (English)

    刘红霞

    2016-01-01

    目的:探讨LH/FSH比值对多囊卵巢综合征的临床诊断意义.方法:选择2013年11月-2015年11月期间本院收治的90例多囊卵巢综合征患者作为观察组,再选择同期体检的60例健康女性为对照组,基于2组LH及FSH常规临检结果分析两组LH/FSH比值的差异.结果:对照组相比,观察组患者LH/FSH比值显著增高,组间比较,差异具有统计学意义(P<0.05).结论:LH/FSH比值升高为多囊卵巢综合征患者重要生殖内分泌改变特征,对多囊卵巢综合征诊断具有较大临床价值.

  6. 基于LH-M10实验箱的模拟智能家居控制系统%Simulate Control System of Smart Home Based on LH-M10 Experiment Box

    Institute of Scientific and Technical Information of China (English)

    舒展

    2016-01-01

    智能家居是家庭自动化的高级阶段,是科技发展的必然结果。基于LH-M10实验箱的模拟智能家居控制系统的设计与开发,设计利用LH-M10实验箱的硬件设备,涵盖了信息数据采集、信息数据处理和信息数据反馈等多个方面,从原理层面实现了智能家居系统中具有代表性的模块展示,并结合智能家居的发展趋势,对此系统后续的研发拓展进行了展望。%Smart homewhich is the advanced stage of Home Automation, is the inevitable result of the development of science and technology. The design and development of this system which named simulate control system of smart home based on LH-M10 experiment box, is using LH-M10 experiment box hardware, and is the demo implement of the typical modules in smart home system. Also this system coversinformation data collection, procession, and feedback. After considering the trend of smart home, the further researching plan has been prospected.

  7. Study of lower hybrid current drive efficiency and its correlation with photon temperatures in the HT-7 tokamak

    Science.gov (United States)

    Younis, J.; Wan, B. N.; Lin, S. Y.; Shi, Y. J.; Ding, B. J.; Gong, X.; HT-7 Team

    2009-07-01

    Lower hybrid current drive (LHCD) efficiency is a very important parameter. The experimental current drive efficiency is defined as η = IrfneR/PLH, where Irf is the current driven by the lower hybrid waves (LHWs), ne is the central line-average density, R is the major radius of the plasma and PLH is the injected LH wave power absorbed by the plasma through Landau damping. A study of current drive efficiency of LHWs in the HT-7 tokamak has been carried out in the parameter ranges: ne = (1.2-2.5) × 1019 m-3, Ip = (80-200) kA, Bt = 1.8 T, PLH = (188-532) kW in the limiter configuration. Current drive efficiency is investigated through a simple correlation with photon temperature and normalized intensity of fast electron bremstrahlung emission, which is, in the first approximation, proportional to the averaged velocity and population of the fast electrons. The plasma current scanning experiment shows that CD efficiency increase is due to the increase in both the photon temperature and the population of the fast electrons generated by LHWs. The density scanning experiment shows that as the plasma density is increased, an increment in CD efficiency along with the increase in the population of fast electrons is observed. The slowing down through the collisions with bulk electrons is mainly responsible for the decreased photon temperature during the plasma density scan. These experiments strongly suggest the dominant role of the population of fast electrons generated by LHCD and the generation of the current carried by fast electrons.

  8. Alterations in bone morphogenetic protein 15, growth differentiation factor 9, and gene expression in granulosa cells in preovulatory follicles of dairy cows given porcine LH.

    Science.gov (United States)

    Behrouzi, Amir; Colazo, Marcos Germán; Ambrose, Divakar Justus

    2016-04-15

    In a previous work, using porcine LH (pLH) in lieu of GnRH for synchronizing ovulation in dairy cows improved pregnancy rates without increasing plasma progesterone concentrations after ovulation. The LH profile is known to remain elevated above basal concentrations (≥1 ng/mL) for up to 20 hours in pLH-treated cows compared to less than 6 hours in GnRH-treated cows. Because LH triggers a cascade of signaling networks in the preovulatory follicle to promote final maturation and support oocyte competence, we hypothesized that dissimilar LH profiles will differentially regulate the intrafollicular factors and expression of downstream genes associated with improved oocyte competence. Specific objectives were to determine differences in the abundance of oocyte-secreted factors in the preovulatory follicular fluid and target genes in granulosa cells associated with oocyte competence, in response to exogenous porcine LH or GnRH-induced endogenous bovine LH exposure, in dairy cows. Follicular contents were aspirated by a transvaginal ultrasound-guided procedure from the preovulatory follicle of cyclic, nonlactating Holstein cows 21 ± 1 hour after administration of either pLH (25-mg) or GnRH (100-μg). Mature forms of bone morphogenetic protein 15, growth differentiation factor 9, and transforming growth factorβ1 were approximately 2-fold more abundant in pLH-treated cows which were exposed to an extended, low LH profile, than in GnRH-treated cows that had a short, high LH profile. The relative abundance of messenger RNA for cyclooxygenase-2, LH receptor, and progesterone receptor in granulosa cells, was about two-, eight-, and two-fold higher, respectively, in cows subjected to pLH than GnRH treatment. We infer that the improved pregnancy rate after pLH-induced ovulation reported previously, occurred through greater activation of intrafollicular transforming growth factor-β1 superfamily members, as these proteins promote cumulus expansion and oocyte competence.

  9. The TTI slowness surface approximation

    KAUST Repository

    Stovas, A.

    2011-01-01

    The relation between the vertical and horizontal slownesses, better known as the dispersion relation, for a transversely isotropic media with titled symmetry axis {left parenthesis, less than bracket}TTI{right parenthesis, greater than bracket} requires solving a quartic polynomial, which does not admit a practical explicit solution to be used, for example, in downward continuation. Using a combination of perturbation theory with respect to the anelliptic parameter and Shanks transform to improve the accuracy of the expansion, we develop an explicit formula for the dispersion relation that is highly accurate for all practical purposes. It also reveals some insights into the anisotropy parameter dependency of the dispersion relation including the low impact that the anelliptic parameter has on the vertical placement of reflectors for small tilt in the symmetry angle. © 2011 Society of Exploration Geophysicists.

  10. Plant domestication slows pest evolution.

    Science.gov (United States)

    Turcotte, Martin M; Lochab, Amaneet K; Turley, Nash E; Johnson, Marc T J

    2015-09-01

    Agricultural practices such as breeding resistant varieties and pesticide use can cause rapid evolution of pest species, but it remains unknown how plant domestication itself impacts pest contemporary evolution. Using experimental evolution on a comparative phylogenetic scale, we compared the evolutionary dynamics of a globally important economic pest - the green peach aphid (Myzus persicae) - growing on 34 plant taxa, represented by 17 crop species and their wild relatives. Domestication slowed aphid evolution by 13.5%, maintained 10.4% greater aphid genotypic diversity and 5.6% higher genotypic richness. The direction of evolution (i.e. which genotypes increased in frequency) differed among independent domestication events but was correlated with specific plant traits. Individual-based simulation models suggested that domestication affects aphid evolution directly by reducing the strength of selection and indirectly by increasing aphid density and thus weakening genetic drift. Our results suggest that phenotypic changes during domestication can alter pest evolutionary dynamics.

  11. Highly Alfvenic Slow Solar Wind

    Science.gov (United States)

    Roberts, D. Aaron

    2010-01-01

    It is commonly thought that fast solar wind tends to be highly Alfvenic, with strong correlations between velocity and magnetic fluctuations, but examples have been known for over 20 years in which slow wind is both Alfvenic and has many other properties more typically expected of fast solar wind. This paper will present a search for examples of such flows from more recent data, and will begin to characterize the general characteristics of them. A very preliminary search suggests that such intervals are more common in the rising phase of the solar cycle. These intervals are important for providing constraints on models of solar wind acceleration, and in particular the role waves might or might not play in that process.

  12. Traditional Procurement is too Slow

    Directory of Open Access Journals (Sweden)

    Ann Kong

    2012-11-01

    Full Text Available This paper reports on an exploratory interview survey of construction project participants aimed at identifying the reasons for the decrease in use of the traditional, lump-sum, procurement system in Malaysia. The results show that most people believe it is too slow. This appears to be in part due to the contiguous nature of the various phase and stages of the process and especially the separation of the design and construction phases. The delays caused by disputes between the various parties are also seen as a contributory factor - the most prominent cause being the frequency of variations, with design and scope changes being a particular source of discontent. It is concluded that an up scaling of the whole of the time related reward/penalty system may be the most appropriate measure for the practice in future.

  13. Chicken granulosa cells show differential expression of epidermal growth factor (EGF) and luteinizing hormone (LH) receptor messenger RNA and differential responsiveness to EGF and LH dependent upon location of granulosa cells to the germinal disc.

    Science.gov (United States)

    Yao, H H; Bahr, J M

    2001-06-01

    Granulosa cells in the chicken follicle exhibit different phenotypes according to their location relative to the germinal disc (GD). Granulosa cells proximal to the GD (referred to as proximal granulosa cells) are more proliferative, whereas granulosa cells distal to the GD (referred to as distal granulosa cells) are more differentiated. We have shown that epidermal growth factor (EGF) derived from the GD stimulated proliferation of granulosa cells proximal to the GD, whereas extraovarian LH promoted differentiation. We tested the hypothesis that phenotypic differences of granulosa cells are the result of differential responsiveness of granulosa cells to EGF and LH. We found that both granulosa and theca layers of chicken preovulatory follicles expressed mRNA for EGF receptor (EGFr) by polymerase chain reaction (PCR) analysis. However, only the granulosa layer showed differential expression of EGFr and LH receptor (LHr) mRNA. Competitive reverse transcription-PCR revealed that proximal granulosa cells expressed more EGFr mRNA but less LHr mRNA than distal granulosa cells. In addition, proximal granulosa cells proliferated more in response to EGF than their distal counterparts. We further demonstrated that EGF decreased LHr mRNA expression by granulosa cells in a dose-dependent manner, whereas EGF and LH had no effect on EGFr mRNA expression except at one dose of LH (15 ng/ml) that stimulated EGFr mRNA expression. Our findings suggest that EGF derived from the GD influences the phenotypes of granulosa cells. Granulosa cells proximal to the GD exhibit a proliferative phenotype possibly because they are exposed to and are more responsive to GD-derived EGF. Furthermore, GD-derived EGF decreases LHr mRNA expression by proximal granulosa cells and therefore results in less differentiated granulosa cell phenotype. In contrast, granulosa cells distal to the GD are not under the influence of EGF and exhibit a more differentiated phenotype.

  14. A mathematical model for LH release in response to continuous and pulsatile exposure of gonadotrophs to GnRH

    Directory of Open Access Journals (Sweden)

    Reed Michael C

    2004-09-01

    Full Text Available Abstract In a previous study, a model was developed to investigate the release of luteinizing hormone (LH from pituitary cells in response to a short pulse of gonadotropin-releasing hormone (GnRH. The model included: binding of GnRH to its receptor (R, dimerization and internalization of the hormone receptor complex, interaction with a G protein, production of inositol 1,4,5-trisphosphate (IP3, release of calcium from the endoplasmic reticulum (ER, entrance of calcium into the cytosol via voltage gated membrane channels, pumping of calcium out of the cytosol via membrane and ER pumps, and release of LH. The extended model, presented in this paper, also includes the following physiologically important phenomena: desensitization of calcium channels; internalization of the dimerized receptors and recycling of some of the internalized receptors; an increase in Gq concentration near the plasma membrane in response to receptor dimerization; and basal rates of synthesis and degradation of the receptors. With suitable choices of the parameters, good agreement with a variety of experimental data of the LH release pattern in response to pulses of various durations, repetition rates, and concentrations of GnRH were obtained. The mathematical model allows us to assess the effects of internalization and desensitization on the shapes and time courses of LH response curves.

  15. Variation in LH pulsatility during 24 h after a postweaning altrenogest treatment in relation to follicle development in primiparous sows

    NARCIS (Netherlands)

    Leeuwen, van J.J.J.; Martens, M.R.T.M.; Jourquin, J.; Draincourt, M.A.; Kemp, B.; Soede, N.M.

    2011-01-01

    This study assessed pulsatile release of LH during altrenogest treatment after weaning in primiparous sows and related this to follicle development, estrus and ovulation rate. Weaned sows (n = 10) received altrenogest 20 mg/day from D-1 to D13 (weaning = D0) at 0800 h. On D13, blood samples were col

  16. Electrochemical stimulation of plasma LH and hypothalamic norepinephrine concentrations at short- and long-term intervals after hypothalamic knife cuts.

    Science.gov (United States)

    Phelps, C P; Saporta, S

    1985-11-18

    Norepinephrine (NE) concentrations in several diencephalic locations were studied in female rats in conjunction with luteinizing hormone (LH) release after medial preoptic area (MPOA) stimulation at short (7 days) and longer time intervals after surgical interruption of anterior or anterolateral neural connections of mediobasal hypothalamus (MBH). Concentrations of diencephalic NE were altered in two general ways after brain surgery: (1) transient early postoperative increases in some regions which appeared unrelated to the type of surgery performed; and (2) other specific decreases in NE concentration which were related to the types of surgery performed and whether a particular ascending noradrenergic pathway was interrupted. At 180 days after surgery, these two types of change in NE concentrations were no longer present. Maximum increases in plasma LH concentrations observed after electrochemical stimulation of the MPOA at either 7 or 180 days after MBH deafferentation also varied according to: (1) the postoperative interval studied; and (2) the location of pathway interruption. Interruption of anterior MBH pathways showed only a transient (7 day interval) reduction in LH release after MPOA stimulation, whereas when both lateral and anterior pathways were severed, there was a more nearly permanent (180 day interval) disruption of LH release after stimulation. The results of these studies support the contention that anterolateral MBH neural connections may constitute a dynamic neural substrate contributing to a gradual improvement in neuroendocrine function observed after early surgical disconnections.

  17. Fluorescence polarization measures energy funneling in single light-harvesting antennas--LH2 vs conjugated polymers.

    Science.gov (United States)

    Camacho, Rafael; Tubasum, Sumera; Southall, June; Cogdell, Richard J; Sforazzini, Giuseppe; Anderson, Harry L; Pullerits, Tõnu; Scheblykin, Ivan G

    2015-10-19

    Numerous approaches have been proposed to mimic natural photosynthesis using artificial antenna systems, such as conjugated polymers (CPs), dendrimers, and J-aggregates. As a result, there is a need to characterize and compare the excitation energy transfer (EET) properties of various natural and artificial antennas. Here we experimentally show that EET in single antennas can be characterized by 2D polarization imaging using the single funnel approximation. This methodology addresses the ability of an individual antenna to transfer its absorbed energy towards a single pool of emissive states, using a single parameter called energy funneling efficiency (ε). We studied individual peripheral antennas of purple bacteria (LH2) and single CP chains of 20 nm length. As expected from a perfect antenna, LH2s showed funneling efficiencies close to unity. In contrast, CPs showed lower average funneling efficiencies, greatly varying from molecule to molecule. Cyclodextrin insulation of the conjugated backbone improves EET, increasing the fraction of CPs possessing ε = 1. Comparison between LH2s and CPs shows the importance of the protection systems and the protein scaffold of LH2, which keep the chromophores in functional form and at such geometrical arrangement that ensures excellent EET.

  18. Fluorescence polarization measures energy funneling in single light-harvesting antennas—LH2 vs conjugated polymers

    Science.gov (United States)

    Camacho, Rafael; Tubasum, Sumera; Southall, June; Cogdell, Richard J.; Sforazzini, Giuseppe; Anderson, Harry L.; Pullerits, Tõnu; Scheblykin, Ivan G.

    2015-01-01

    Numerous approaches have been proposed to mimic natural photosynthesis using artificial antenna systems, such as conjugated polymers (CPs), dendrimers, and J-aggregates. As a result, there is a need to characterize and compare the excitation energy transfer (EET) properties of various natural and artificial antennas. Here we experimentally show that EET in single antennas can be characterized by 2D polarization imaging using the single funnel approximation. This methodology addresses the ability of an individual antenna to transfer its absorbed energy towards a single pool of emissive states, using a single parameter called energy funneling efficiency (ε). We studied individual peripheral antennas of purple bacteria (LH2) and single CP chains of 20 nm length. As expected from a perfect antenna, LH2s showed funneling efficiencies close to unity. In contrast, CPs showed lower average funneling efficiencies, greatly varying from molecule to molecule. Cyclodextrin insulation of the conjugated backbone improves EET, increasing the fraction of CPs possessing ε = 1. Comparison between LH2s and CPs shows the importance of the protection systems and the protein scaffold of LH2, which keep the chromophores in functional form and at such geometrical arrangement that ensures excellent EET. PMID:26478272

  19. Hybrid Metaheuristics

    CERN Document Server

    2013-01-01

    The main goal of this book is to provide a state of the art of hybrid metaheuristics. The book provides a complete background that enables readers to design and implement hybrid metaheuristics to solve complex optimization problems (continuous/discrete, mono-objective/multi-objective, optimization under uncertainty) in a diverse range of application domains. Readers learn to solve large scale problems quickly and efficiently combining metaheuristics with complementary metaheuristics, mathematical programming, constraint programming and machine learning. Numerous real-world examples of problems and solutions demonstrate how hybrid metaheuristics are applied in such fields as networks, logistics and transportation, bio-medical, engineering design, scheduling.

  20. Slow Light in Metamaterial Waveguides

    CERN Document Server

    Lavoie, Benjamin R

    2013-01-01

    Metamaterials, which are materials engineered to possess novel optical properties, have been increasingly studied. The ability to fabricate metamaterials has sparked an interest in determining possible applications. We investigate using a metamaterial for boundary engineering in waveguides. A metamaterial-clad cylindrical waveguide is used to provide confinement for an optical signal, thereby increasing the local electromagnetic energy density. We show that metamaterial-clad waveguides have unique optical properties, including new modes, which we call hybrid modes. These modes have properties of both ordinary guided modes and surface plasmon-polariton modes. We show that for certain metamaterial parameters, the surface plasmon-polariton modes of a metamaterial-clad waveguide have less propagation loss than those of a metal-clad guide with the same permittivity. This low-loss mode is exploited for all-optical control of weak fields. Embedding three-level {\\Lambda} atoms in the dielectric core of a metamaterial...

  1. EFFECT OF INVIVO PRETREATMENT WITH ESTRADIOL AND EITHER GNRH, GNRH AGONISTIC ANALOG OR GNRH ANTAGONISTIC ANALOG ON GNRH-STIMULATED SECRETION OF LH INVITRO

    NARCIS (Netherlands)

    SCHUILING, GA; KOITER, TR; MOES, H

    1991-01-01

    In vivo treatment with GnRH or with GnRH agonistic analog (AG), but not with GnRH antagonistic analog (ANT), depleted the LH stores of the rat pituitary gland. This depletion was potentiated by oestradiol. Oestradiol augmented the in vitro LH response of the pituitary gland to GnRH. This augmenting

  2. A common polymorphic allele of the LH beta-subunit gene is associated with higher exogenous FSH consumption during controlled ovarian stimulation for assisted reproductive technology

    DEFF Research Database (Denmark)

    Alviggi, Carlo; Pettersson, Kim; Longobardi, Salvatore

    2013-01-01

    a long GnRH-agonist down-regulation protocol received an individualized dose of r-hFSH (100 IU and 375 IU s.c. daily) according to antral follicle count, baseline FSH, body mass index and age. The LH genotype was assessed in all patients by immunofluorometric assay. RESULTS: V-betaLH was present in 11...

  3. Importance of intense male sexual behavior for inducing the preovulatory LH surge and ovulation in seasonally anovulatory female goats.

    Science.gov (United States)

    Martínez-Alfaro, J C; Hernández, H; Flores, J A; Duarte, G; Fitz-Rodríguez, G; Fernández, I G; Bedos, M; Chemineau, P; Keller, M; Delgadillo, J A; Vielma, J

    2014-10-15

    The present study was carried out to determine whether the presence of photostimulated sedated male goats could stimulate the LH preovulatory surge and ovulation in seasonal anestrous goats. Sexually experienced male goats were treated with artificial long days (16 hours light per day) from 1 November to 15 January to stimulate their sexual activity in March and April, corresponding to the natural sexual rest. A female group of goats (n=20) was exposed to non-sedated males who displayed an intense sexual behavior and provided strong odor (non-sedated group). Another female group of goats (n=20) was exposed to the photo-stimulated male goats, but these males were sedated with Xylazine 2% to prevent the expression of sexual behavior (sedated group). The sedated males also provided a strong odor. Females of both groups had full physical and visual contact with non-sedated or sedated males. In both groups, the males remained with females during 4 days. The LH preovulatory surge of 10 female goats per group was measured by determination of LH plasma concentrations in samples taken every 3 hours. In addition, in all goats, (n=20 by group), ovulation was determined by measuring plasma concentrations of progesterone. The proportion of female goats showing a preovulatory LH surge was higher in goats exposed to non-sedated (10/10) than in those exposed to sedated bucks (0/10; Psexual behavior by male goats is necessary to induce LH preovulatory surge and ovulation in seasonally anovulatory goats. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Ghrelin suppresses nocturnal secretion of luteinizing hormone (LH) and thyroid stimulating hormone (TSH) in patients with major depression.

    Science.gov (United States)

    Kluge, Michael; Schmidt, Doreen; Uhr, Manfred; Steiger, Axel

    2013-09-01

    Major depression is associated with various endocrine disturbances. Apart from the well-known hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis, also the function of the hypothalamic-pituitary-gonadal (HPG) axis and of the hypothalamic-pituitary-thyroid (HPT) axis may be altered compared to healthy subjects. The orexigenic hormone ghrelin is involved in mood regulation and may have antidepressant effects. In addition, it has been shown to suppress secretion of luteinizing hormone (LH) and thyroid stimulating hormone (TSH) in healthy subjects. Aim of this study was therefore to test the effect of ghrelin on the activity of the HPG and HPT axis in patients with major depression. Therefore, secretion profiles of LH and TSH were determined in 14 unmedicated patients with major depression (7 women) twice, receiving 50 μg ghrelin or placebo at 2200, 2300, 0000, and 0100 h. LH secretion after ghrelin injection as assessed by the AUC (4.05 ± 1.18 mlIU min/ml) was significantly (P = 0.049) lower than after placebo injection (4.75 ± 1.33 mlIU min/ml) during the predefined intervention period (2220-0200 h). In addition, LH pulses occurred significantly (P = 0.045) less frequently after ghrelin injection (3.2 ± 1.4) than after placebo injection (3.9 ± 1.7). Mean TSH plasma levels were significantly lower at 0240 h and from 0320 until 0420 h after ghrelin injection than after placebo injection. In conclusion, ghrelin suppressed nocturnal secretion of LH and TSH in patients with major depression. However, these effects were weaker than previously shown in healthy subjects.

  5. The origin of the split B800 absorption peak in the LH2 complexes from Allochromatium vinosum.

    Science.gov (United States)

    Löhner, Alexander; Carey, Anne-Marie; Hacking, Kirsty; Picken, Nichola; Kelly, Sharon; Cogdell, Richard; Köhler, Jürgen

    2015-01-01

    The absorption spectrum of the high-light peripheral light-harvesting (LH) complex from the photosynthetic purple bacterium Allochromatium vinosum features two strong absorptions around 800 and 850 nm. For the LH2 complexes from the species Rhodopseudomonas acidophila and Rhodospirillum molischianum, where high-resolution X-ray structures are available, similar bands have been observed and were assigned to two pigment pools of BChl a molecules that are arranged in two concentric rings (B800 and B850) with nine (acidophila) or eight (molischianum) repeat units, respectively. However, for the high-light peripheral LH complex from Alc. vinosum, the intruiging feature is that the B800 band is split into two components. We have studied this pigment-protein complex by ensemble CD spectroscopy and polarisation-resolved single-molecule spectroscopy. Assuming that the high-light peripheral LH complex in Alc. vinosum is constructed on the same modular principle as described for LH2 from Rps. acidophila and Rsp. molischianum, we used those repeat units as a starting point for simulating the spectra. We find the best agreement between simulation and experiment for a ring-like oligomer of 12 repeat units, where the mutual arrangement of the B800 and B850 rings resembles those from Rsp. molischianum. The splitting of the B800 band can be reproduced if both an excitonic coupling between dimers of B800 molecules and their interaction with the B850 manifold are taken into account. Such dimers predict an interesting apoprotein organisation as discussed below.

  6. Comparison of platelet counts by sysmex XE 2100 and LH-750 with the international flow reference method in thrombocytopenic patients

    Directory of Open Access Journals (Sweden)

    Tina Dadu

    2013-01-01

    Full Text Available Background: There are several methods for counting platelets, of which the international flow reference method (IRM is considered to be the gold standard. We compared the platelet count given by this method to the count given by automated analyzers using other methods, such as optical fluorescence and impedance. Aims: The aim of this study is to compare the platelet counts obtained by Sysmex XE 2100 by Impedance (Sysmex-I, optical florescence (Sysmex-O and reported (Sysmex-R based on the switching algorithm and LH-750 by Impedance (LH-750 with the IRM in thrombocytopenic blood samples. To calculate the sensitivity, specificity, positive predictive value (PPV and negative predictive value (NPV of various technologies at the clinically relevant transfusion thresholds of 10 × 10 9 /l and 20 × 10 9 /l. Materials and Methods: A total of 118 blood samples with platelet count of <50 × 10 9 /l were selected for the study. Platelet counts of all samples were analyzed by all methods using the Sysmex analyzer, LH-750 and IRM in parallel within 6 h of collection. Statistical Analysis Used: Pearson correlation, bland Altman analysis, sensitivity and specificity, PPV and NPV. Results and Conclusions: Sysmex-R had the least Bias and 95% limits of agreement (95%LA range and thus correlated best with IRM values. LH-750 had a higher Bias compared to Sysmex-O and Sysmex-R, but a strikingly similar 95% LA ensures similar results in all three methods. In fact, in the oncology subset, it had the narrowest 95% LA, which made it the best performer in this subgroup. Of the three Sysmex results, Sysmex-I had the highest bias, widest 95% LA and highest potential risk of over transfusion. Hence, Sysmex-R and LH-750 were found to be reliable tools for estimation of platelet count in thrombocytopenic patients.

  7. Developmental programming: Prenatal BPA treatment disrupts timing of LH surge and ovarian follicular wave dynamics in adult sheep

    Energy Technology Data Exchange (ETDEWEB)

    Veiga-Lopez, A.; Beckett, E.M.; Abi Salloum, B. [Department of Pediatrics, University of Michigan, Ann Arbor, MI (United States); Ye, W. [Department of Biostatistics, University of Michigan, Ann Arbor, MI (United States); Padmanabhan, V., E-mail: vasantha@umich.edu [Department of Pediatrics, University of Michigan, Ann Arbor, MI (United States); The Reproductive Sciences Program, University of Michigan, Ann Arbor, MI (United States)

    2014-09-01

    Developmental exposure to BPA adversely affects reproductive function. In sheep, prenatal BPA treatment induces reproductive neuroendocrine defects, manifested as LH excess and dampened LH surge and perturbs early ovarian gene expression. In this study we hypothesized that prenatal BPA treatment will also disrupt ovarian follicular dynamics. Pregnant sheep were treated from days 30 to 90 of gestation with 3 different BPA doses (0.05, 0.5, or 5 mg/kg BW/day). All female offspring were estrus synchronized and transrectal ultrasonography was performed daily for 22 days to monitor ovarian follicular and corpora lutea dynamics. Blood samples were collected to assess preovulatory hormonal changes and luteal progesterone dynamics. Statistical analysis revealed that the time interval between the estradiol rise and the preovulatory LH surge was shortened in the BPA-treated females. None of the three BPA doses had an effect on corpora lutea, progestogenic cycles, and mean number or duration of ovulatory and non-ovulatory follicles. However, differences in follicular count trajectories were evident in all three follicular size classes (2–3 mm, 4–5 mm, and ≥ 6 mm) of prenatal BPA-treated animals compared to controls. Number of follicular waves tended also to be more variable in the prenatal BPA-treated groups ranging from 2 to 5 follicular waves per cycle, while this was restricted to 3 to 4 waves in control females. These changes in ovarian follicular dynamics coupled with defects in time interval between estradiol rise and preovulatory LH release are likely to lead to subfertility in prenatal BPA-treated females. - Highlights: • Prenatal BPA shortens interval between estradiol rise and preovulatory LH surge. • Prenatal BPA affects follicular count trajectory and follicular wave occurrence. • Prenatal BPA does not affect ovulatory rate and progesterone dynamics.

  8. Electrical potential-assisted DNA hybridization. How to mitigate electrostatics for surface DNA hybridization.

    Science.gov (United States)

    Tymoczko, Jakub; Schuhmann, Wolfgang; Gebala, Magdalena

    2014-12-24

    Surface-confined DNA hybridization reactions are sensitive to the number and identity of DNA capture probes and experimental conditions such as the nature and the ionic strength of the electrolyte solution. When the surface probe density is high or the concentration of bulk ions is much lower than the concentration of ions within the DNA layer, hybridization is significantly slowed down or does not proceed at all. However, high-density DNA monolayers are attractive for designing high-sensitivity DNA sensors. Thus, circumventing sluggish DNA hybridization on such interfaces allows a high surface concentration of target DNA and improved signal/noise ratio. We present potential-assisted hybridization as a strategy in which an external voltage is applied to the ssDNA-modified interface during the hybridization process. Results show that a significant enhancement of hybridization can be achieved using this approach.

  9. Efficient tunable switch from slow light to fast light in quantum opto-electromechanical system

    CERN Document Server

    Akram, M Javed; Saif, Farhan

    2015-01-01

    The control of slow and fast light propagation, in the probe transmission in a single experiment, is a challenging task. This type of control can only be achieved through highly nonlinear interactions and additional interfering pathway(s), which is therefore seldom reported. Here, we devise a scheme in which slow light, and a tunable switch from slow light to fast light can be achieved in the probe transmission based on a hybrid setup, which is composed of an optical cavity with two charged nano mechanical resonators (MRs). The two MRs are electrostatically coupled via tunable Coulomb coupling strength ($g_{c}$) making a quantum opto-electromechanical system (QOEMS). The parameter $g_{c}$ that couples the two MRs can be switched on and off by controlling the bias voltages on the MRs, and acts as a tunable switch that allows the propagation of transmitted probe field as slow light ($g_{c} \

  10. Effects of endocannabinoid 1 and 2 (CB1; CB2) receptor agonists on luteal weight, circulating progesterone, luteal mRNA for luteinizing hormone (LH) receptors, and luteal unoccupied and occupied receptors for LH in vivo in ewes.

    Science.gov (United States)

    Tsutahara, Nicole M; Weems, Yoshie S; Arreguin-Arevalo, J Alejandro; Nett, Torrance M; LaPorte, Magen E; Uchida, Janelle; Pang, Janelle; McBride, Tonya; Randel, Ronald D; Weems, Charles W

    2011-02-01

    Thirty to forty percent of ruminant pregnancies are lost during the first third of gestation due to inadequate progesterone secretion. During the estrous cycle, luteinizing hormone (LH) regulates progesterone secretion by small luteal cells (SLC). Loss of luteal progesterone secretion during the estrous cycle is increased via uterine secretion of prostaglandin F(2α) (PGF(2α)) starting on days 12-13 post-estrus in ewes with up to 4-6 pulses per day. Prostaglandin F(2α) is synthesized from arachidonic acid, which is released from phospholipids by phospholipase A2. Endocannabinoids are also derived from phospholipids and are associated with infertility. Endocannabinoid-induced infertility has been postulated to occur primarily via negative effects on implantation. Cannabinoid (CB) type 1 (CB1) or type 2 (CB2) receptor agonists and an inhibitor of the enzyme fatty acid amide hydrolase, which catabolizes endocannabinoids, decreased luteal progesterone, prostaglandin E (PGE), and prostaglandin F(2α) (PGF(2α)) secretion by the bovine corpus luteum in vitro by 30 percent. The objective of the experiment described herein was to determine whether CB1 or CB2 receptor agonists given in vivo affect circulating progesterone, luteal weights, luteal mRNA for LH receptors, and luteal occupied and unoccupied LH receptors during the estrous cycle of ewes. Treatments were: Vehicle, Methanandamide (CB1 agonist; METH), or 1-(4-chlorobenzoyl)-5-methoxy-1H-indole-3-acetic acid morpholineamide (CB2 agonist; IMMA). Ewes received randomized treatments on day 10 post-estrus. A single treatment (500 μg; N=5/treatment group) in a volume of 1 ml was given into the interstitial tissue of the ovarian vascular pedicle adjacent to the luteal-containing ovary. Jugular venous blood was collected at 0 h and every 6-48 h for the analysis of progesterone by radioimmunoassay (RIA). Corpora lutea were collected at 48 h, weighed, bisected, and frozen in liquid nitrogen until analysis of unoccupied and

  11. Femtosecond Dynamics of Energy Transfer in Native B800-B850 and B800-Released LH2 Complexes of Rhodobacter Sphaeroides

    Institute of Scientific and Technical Information of China (English)

    刘伟民; 朱荣毅; 夏辰安; 刘源; 徐春和; 钱士雄

    2003-01-01

    Two kinds of antenna complexes LH2 of Rhodobacter sphaeroides, wild type RS601 and the removal of B800 pigments (B800-released), were used in our experiment. These two LH2 complexes show quite different behaviour in absorption and femtosecond dynamics. By using the femtosecond pump-probe technique, the energy transfer processes occurring in two complexes were studied. Because of removing the B800 pigment from the LH2 in B800-released LH2 complex, the energy transfer between the B800 to B850 pigment was completely eliminated,while the pure internal energy transfer within the exciton states of B850 pigment could be carefully investigated.The results show that, at B800 absorption band, B800-released LH2 obviously shows a dominated transient absorption different from the photobleaching observed in RS601; while at the B850 band, these two complexes show similar photobleaching behaviour.

  12. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  13. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available effect was observed for the elongation at break of the hybrid composites. The impact strength of the hybrid composites increased with the addition of glass fibres. The tensile and impact properties of thermoplastic natural rubber reinforced short... panels made from conventional structural materials. Figure 3 illustrates the performance of cellular biocomposite panels against conventional systems used for building and residential construction, namely a pre- cast pre-stressed hollow core concrete...

  14. Slow dynamics in proteins and polymer chains

    Science.gov (United States)

    Hu, Chin-Kun

    2013-02-01

    How a biological system can maintain in a non-equilibrium state for a very long time and why proteins aggregate are still not well understood. In this paper, we first review critical slow down of the Ising model and slow relaxation of a spin-glass model at low temperatures. The data indicate that relaxation of the spin glass model at low temperatures can be slower than the critical slowing down of the Ising model. We then review recent molecular dynamics results for the slow relaxation of polymer chains and experimental data for the glassy behavior of collagen fibrils. The slow dynamics in polymer chains and collagen fibrils can provide clues for understanding why a biological system can maintain in a non-equilibrium state for a very long time, and how to slow down protein aggregation related to neurodegenerative diseases.

  15. Biological activities of recombinant equine luteinizing hormone/chorionic gonadotropin (eLH/CG) expressed in Sf9 and Mimic insect cell lines.

    Science.gov (United States)

    Legardinier, Sébastien; Duonor-Cérutti, Martine; Devauchelle, Gérard; Combarnous, Yves; Cahoreau, Claire

    2005-02-01

    Equine luteinizing hormone (eLH) and chorionic gonadotropin (eCG) are composed of identical alpha and beta polypeptide chains, but eCG subunits are much more heavily glycosylated and sialylated. Consequently, eCG exhibits a much longer half-life than eLH in blood. Recombinant eLH/CG, expressed in Sf9 and Mimic insect cells, were compared with one another and to the natural hormones eCG and eLH. Mimic cells are stably-transformed Sf9 cells, expressing five mammalian genes encoding glycosyltransferases involved in the synthesis of complex N-carbohydrate chains. Recombinant eLH/CG expressed in Mimic cells exhibited a higher apparent molecular weight (MW) than that expressed in Sf9 cells, suggesting that its N-glycosylation was, as expected, more complete. Nevertheless, the two recombinant eLH/CG exhibited lower MW than natural eCG from pregnant mare plasma. The two eLH/CG produced in Sf9 and Mimic cells were found to be active in in vitro LH and FSH bioassays, with potencies similar to those of eCG. By contrast, they exhibited no significant in vivo bioactivity, neither in the specific follicle-stimulating hormone (FSH) assay nor in the specific eCG assay. Although recombinant eLH/CG produced in Mimic cells bears more elaborate carbohydrate chains than recombinant eLH/CG from Sf9 cells, it exhibits no significant in vivo bioactivity, probably because of insufficient terminal sialylation of its carbohydrate chains, leading to its rapid removal from blood.

  16. Effects of estradiol-17beta administration on steady-state messenger ribonucleic acid (MRNA) encoding equine alpha and LH/CGbeta subunits in pituitaries of ovariectomized pony mares.

    Science.gov (United States)

    Sharp, D C; Wolfe, M W; Cleaver, B D; Nilson, J

    2001-03-15

    The process of sexual recrudescence in the springtime in mares is characterized by renewal of follicular growth and acquisition of steroidogenic competence. Concomitant with renewal of follicular steroidogenesis is re-establishment of LH biosynthesis and secretion. Research results from our laboratory indicate that increased estradiol and LH secretion occur in close temporal association before the first ovulation of the year. Therefore, the hypothesis tested in this experiment was that estrogen administration to ovariectomized pony mares during the equivalent time of early vernal transition would enhance LH biosynthesis as monitored by messenger ribonucleic acid (mRNA) encoding for the pituitary subunits of LH (alpha and LH/CGbeta). Mares were administered either sesame oil vehicle control, or estradiol (5 mg i.m. twice daily in sesame oil) for 3, 6 or 9 days, beginning on February 2. The pituitary glands were harvested, and examined for LH subunit mRNA by Northern Blot and slot blot analysis. There was a significant increase in LH secretion after 6 days of estradiol secretion compared with control vehicle administration. Similarly, there was a significant increase in both alpha and LH/CGbeta subunit mRNA when estradiol was administered for 9 days. These data indicate that estrogen stimulates LH subunit formation in mares during early equivalent vernal transition. These data do not, however, discriminate between a direct pituitary effect of estrogen, and a hypothalamic effect. Whether the surge of estradiol just prior to the first ovulation of the year is essential for the renewed biosynthesis of LH subunits cannot be determined from these data. However an important role of estrogen in the final stages of sexual recrudescence is indicated.

  17. LH-Induced Steroidogenesis in the Mouse Ovary, but Not Testis, Requires Matrix Metalloproteinase 2- and 9-Mediated Cleavage of Upregulated EGF Receptor Ligands.

    Science.gov (United States)

    Light, Allison; Hammes, Stephen R

    2015-09-01

    Oocyte maturation and cumulus cell expansion depend on luteinizing hormone (LH)-mediated upregulation of membrane-bound epidermal growth factor (EGF)-like ligands, including amphiregulin, epiregulin, and betacellulin. These ligands then transactivate the EGF receptor (EGFR) after release by matrix metalloproteinases (MMPs). However, direct measurement of released EGF-like ligands or MMPs from granulosa cells has not been formally evaluated, nor has direct identification of responsible MMPs. Here we address these issues by analyzing LH-induced steroidogenesis, which is also MMP and EGFR dependent, in freshly isolated mouse primary granulosa cells. We demonstrate a correlation between amphiregulin and epiregulin mRNA induction and steroid production in LH-treated granulosa cells as well as in ovaries of human chorionic gonadotropin-treated mice. In contrast, LH does not alter Mmp1, Mmp2, Mmp3, Mmp8, Mmp9, or Adam17 mRNA expression. We demonstrate that, in primary mouse granulosa cells, LH triggers release of soluble amphiregulin that correlates with steroid production, both of which are blocked by MMP2/9 inhibition, confirming that MMP2/9 likely regulates LH-induced amphiregulin release and downstream processes. Notably, LH does not alter secretion of MMP2/9 from primary granulosa cells, nor does it modulate MMP activity. These findings indicate that, in the ovary, LH dictates EGFR-mediated processes not by regulating MMPs, but instead by increasing EGF-like ligand availability. In contrast, LH stimulation of primary mouse Leydig cells does not induce EGF-like ligand expression or require MMP2/9 for steroidogenesis, confirming marked differences in LH receptor-induced processes in the testes. Our results suggest that MMP inhibition may be a means of attenuating excess ovarian steroid production in diseases like polycystic ovary syndrome.

  18. Slow Tourism Now and in the Future

    OpenAIRE

    Soininen, Tiia

    2011-01-01

    This thesis consists of a research to a new tourism trend; slow tourism. Tourism industry alters continuously and new forms of tourism are created all the time. The focus was given to slow tourism and travel because it has begun during the last decade in Italy from Slow Movement and it is an encounter to speed travelling and mass tourism. Slow tourism was identified with travelling slowly, living in the local culture and valuing sustainability. The main goal in the research was to find o...

  19. Downregulation of LH receptor mRNA in the rat uterus.

    Science.gov (United States)

    Kasahara, Yoshimitsu; Kitahara, Yoshikazu; Nakamura, Kazuto; Minegishi, Takashi

    2012-05-01

    We detected luteinizing hormone receptor (LHR) mRNA in the immature rat uterus by northern blotting and downregulation of this receptor mRNA after pregnant mare serum gonadotropin (PMSG)-human chorionic gonadotropin (hCG) treatment. After administration of hCG, the mRNA levels in the rat uterus declined to an extremely low level from Days 1 to 3 and then rebounded and reached higher than pretreatment values at Day 4. At Day 5 the levels were 3-fold higher than the control levels. The cultured uterus displayed an hCG concentration-dependent increase in cAMP production in the medium. Immunohistochemical experiments showed that these receptor proteins were expressed in the epithelial cells of the endometrium. These results suggest that functional LHRs are present in the immature rat uterus and are downregulated by signals resulting from hCG treatment. These data may support the idea that LH acts on the uterus to inhibit contraction at ovulation. Although the precise role of the LHR in the uterus remains unknown, this study may provide a model with which to investigate the regulation of LHR.

  20. Bioconversion of ginsenoside Rb1 into compound K by Leuconostoc citreum LH1 isolated from kimchi

    Directory of Open Access Journals (Sweden)

    Lin-Hu Quan

    2011-09-01

    Full Text Available About 40 different types of ginsenoside (ginseng saponin, a major pharmacological component of ginseng, have been identified along with their physiological activities. Among these, compound K has been reported to prevent the development of and the metastasis of cancer by blocking the formation of tumors and suppressing the invasion of cancerous cells. In this study, ginsenoside Rb1 was converted into compound K via interaction with the enzyme secreted by β-glucosidase active bacteria, Leuconostoc citreum LH1, extracted from kimchi. The optimum time for the conversion of Rb1 to compound K was about 72 hrs at a constant pH of 6.0 and an optimum temperature of about 30ºC. Under optimal conditions, ginsenoside Rb1 was decomposed and converted into compound K by 72 hrs post-reaction (99%. Both TLC and HPLC were used to analyze the enzymatic reaction. Ginsenoside Rb1 was consecutively converted to ginsenoside Rd, F2, and compound K via the hydrolyses of 20-C β-(1 → 6-glucoside, 3-C β-(1 → 2glucoside, and 3-C β-glucose of ginsenoside Rb1.

  1. Ultrafast excitation relaxation in light-harvesting complex LH2 from Rb.sphaeroides 601

    Institute of Scientific and Technical Information of China (English)

    GUO Lijun; LIU Yuan; LIU Weimin; GUO Junhua; XU Chunhe; QIAN Shixiong

    2004-01-01

    The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2 from Rb. Sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783 nm excitation, the energy at B800 BChls experiences an intramolecular redistribution with 0.35 ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher excitonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by interconversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

  2. Ultrafast excitation relaxation in light-harvesting complex LH2 from Rb. sphaeroides 601

    Institute of Scientific and Technical Information of China (English)

    GUO; Lijun; LIU; Yuan; LIU; Weimin; GUO; Junhua; XU; Chunhe

    2004-01-01

    The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2 from Rb. Sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783 nm excitation, the energy at B800 BChls experiences an intramolecular redistribution with 0.35 ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher excitonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by interconversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

  3. LH2 tank pressure control by thermodynamic vent system (TVS) at zero gravity

    Science.gov (United States)

    Wang, B.; Huang, Y. H.; Chen, Z. C.; Wu, J. Y.; Li, P.; Sun, P. J.

    2017-02-01

    Thermodynamic vent system (TVS) is employed for pressure control of propellant tanks at zero gravity. An analytical lumped parameter model is developed to predict pressure variation in an 18.09 m3 liquid hydrogen tank equipped with TVS. Mathematical simulations are carried out assuming tank is filled up to 75% volume (liquid mass equals to 945 kg) and is subjected to heat flux of 0.76 W/m2. Tank pressure controls at 165.5-172.4, 165.5-179.3 and 165.5-182.2 kPa are compared with reference to number of vent cycles, vent duration per cycle and loss of hydrogen. Analysis results indicate that the number of vent cycles significantly decreases from 62 to 21 when tank pressure control increases from 6.9 to 20.4 kPa. Also, duration of vent cycle increases from 63 to 152 and cycle duration decreases from 3920 to 3200 s. Further, the analysis result suggests that LH2 evaporation loss per day decreases from 0.17 to 0.14%. Based on the results of analysis, TVS is found effective in controlling the propellant tank pressure in zero gravity.

  4. Pueraria tuberosa DC Extract Improves Androgenesis and Sexual Behavior via FSH LH Cascade

    Directory of Open Access Journals (Sweden)

    Nagendra Singh Chauhan

    2013-01-01

    Full Text Available The aim of this study was to investigate the effects of ethanolic extract of Pueraria tuberosa (PT on sexual behaviour and androgenic activity. Male albino rats were divided into four groups of six animals each: control group 1 (2% acacia solution, PT-treated group 2 (50 mg/Kg, PT-treated group 3 (100 mg/Kg, and PT-treated group 4 (150 mg/Kg. Sexual behavior of male rats in the presence of a female rat was recorded. The treated groups were evaluated for sexual parameters. The extract was characterized using LC-MS. The effect of treatment on anabolic and weight of secondary sexual organs was determined. The histological changes in section of testis and epididymis after treatment were observed. Sperm count in epididymis and fructose content in seminal vesicles were also measured. Levels of hormones like FSH, LH, and T were determined. A dose-dependent increase in sexual behaviors was evidenced in the animals of extract treated groups. Increase in testis weight was recorded in PT. At the highest dose PT also affects the hormones level. The four compounds namely puerarin, daidzein, biochanin-A and formononetin were identified in ethanolic extract using LC-MS. It concluded that PT extract possesses androgenic effect and it significantly increased the sexual behaviour and hormones level.

  5. Thermal stratification in LH2 tank of cryogenic propulsion stage tested in ISRO facility

    Science.gov (United States)

    Xavier, M.; Raj, R. Edwin; Narayanan, V.

    2017-02-01

    Liquid oxygen and hydrogen are used as oxidizer and fuel respectively in cryogenic propulsion system. These liquids are stored in foam insulated tanks of cryogenic propulsion system and are pressurized using warm pressurant gas supplied for tank pressure maintenance during cryogenic engine operation. Heat leak to cryogenic propellant tank causes buoyancy driven liquid stratification resulting in formation of warm liquid stratum at liquid free surface. This warm stratum is further heated by the admission of warm pressurant gas for tank pressurization during engine operation. Since stratified layer temperature has direct bearing on the cavitation free operation of turbo pumps integrated in cryogenic engine, it is necessary to model the thermal stratification for predicting stratified layer temperature and mass of stratified liquid in tank at the end of engine operation. These inputs are required for estimating the minimum pressure to be maintained by tank pressurization system. This paper describes configuration of cryogenic stage for ground qualification test, stage hot test sequence, a thermal model and its results for a foam insulated LH2 tank subjected to heat leak and pressurization with hydrogen gas at 200 K during liquid outflow at 38 lps for engine operation. The above model considers buoyancy flow in free convection boundary layer caused by heat flux from tank wall and energy transfer from warm pressurant gas etc. to predict temperature of liquid stratum and mass of stratified liquid in tank at the end of engine operation in stage qualification tests carried out in ISRO facility.

  6. Hybrid Natural Inflation

    Science.gov (United States)

    Ross, Graham G.; Germán, Gabriel; Vázquez, J. Alberto

    2016-05-01

    We construct two simple effective field theory versions of Hybrid Natural Inflation (HNI) that illustrate the range of its phenomenological implications. The resulting inflationary sector potential, V = Δ4(1 + acos( ϕ/f)), arises naturally, with the inflaton field a pseudo-Nambu-Goldstone boson. The end of inflation is triggered by a waterfall field and the conditions for this to happen are determined. Also of interest is the fact that the slow-roll parameter ɛ (and hence the tensor r) is a non-monotonic function of the field with a maximum where observables take universal values that determines the maximum possible tensor to scalar ratio r. In one of the models the inflationary scale can be as low as the electroweak scale. We explore in detail the associated HNI phenomenology, taking account of the constraints from Black Hole production, and perform a detailed fit to the Planck 2015 temperature and polarisation data.

  7. Profiling of FSHR negative allosteric modulators on LH/CGR reveals biased antagonism with implications in steroidogenesis.

    Science.gov (United States)

    Ayoub, Mohammed Akli; Yvinec, Romain; Jégot, Gwenhaël; Dias, James A; Poli, Sonia-Maria; Poupon, Anne; Crépieux, Pascale; Reiter, Eric

    2016-11-15

    Biased signaling has recently emerged as an interesting means to modulate the function of many G protein-coupled receptors (GPCRs). Previous studies reported two negative allosteric modulators (NAMs) of follicle-stimulating hormone receptor (FSHR), ADX68692 and ADX68693, with differential effects on FSHR-mediated steroidogenesis and ovulation. In this study, we attempted to pharmacologically profile these NAMs on the closely related luteinizing hormone/chorionic gonadotropin hormone receptor (LH/CGR) with regards to its canonical Gs/cAMP pathway as well as to β-arrestin recruitment in HEK293 cells. The NAMs' effects on cAMP, progesterone and testosterone production were also assessed in murine Leydig tumor cell line (mLTC-1) as well as rat primary Leydig cells. We found that both NAMs strongly antagonized LH/CGR signaling in the different cell models used with ADX68693 being more potent than ADX68692 to inhibit hCG-induced cAMP production in HEK293, mLTC-1 and rat primary Leydig cells as well as β-arrestin 2 recruitment in HEK293 cells. Interestingly, differential antagonism of the two NAMs on hCG-promoted steroidogenesis in mLTC-1 and rat primary Leydig cells was observed. Indeed, a significant inhibition of testosterone production by the two NAMs was observed in both cell types, whereas progesterone production was only inhibited by ADX68693 in rat primary Leydig cells. In addition, while ADX68693 totally abolished testosterone production, ADX68692 had only a partial effect in both mLTC-1 and rat primary Leydig cells. These observations suggest biased effects of the two NAMs on LH/CGR-dependent pathways controlling steroidogenesis. Interestingly, the pharmacological profiles of the two NAMs with respect to steroidogenesis were found to differ from that previously shown on FSHR. This illustrates the complexity of signaling pathways controlling FSHR- and LH/CGR-mediated steroidogenesis, suggesting differential implication of cAMP and β-arrestins mediated by

  8. Fast renal trapping of porcine Luteinizing Hormone (pLH shown by 123I-scintigraphic imaging in rats explains its short circulatory half-life

    Directory of Open Access Journals (Sweden)

    Locatelli Alain

    2003-10-01

    Full Text Available Abstract Background Sugar moieties of gonadotropins play no primary role in receptor binding but they strongly affect their circulatory half-life and consequently their in vivo biopotencies. In order to relate more precisely hepatic trapping of these glycoproteic hormones with their circulatory half-life, we undertook a comparative study of the distribution and elimination of porcine LH (pLH and equine CG (eCG which exhibit respectively a short and a long half-life. This was done first by following half-lives of pLH in piglets with hepatic portal circulation shunted or not. It was expected that such a shunt would enhance the short half-life of pLH. Subsequently, scintigraphic imaging of both 123I-pLH and 123I-eCG was performed in intact rats to compare their routes and rates of distribution and elimination. Methods Native pLH or eCG was injected to normal piglets and pLH was tested in liver-shunted anæsthetized piglet. Blood samples were recovered sequentially over one hour time and the hormone concentrations were determined by a specific ELISA method. Scintigraphic imaging of 123I-pLH and 123I-eCG was performed in rats using a OPTI-CGR gamma camera. Results In liver-shunted piglets, the half-life of pLH was found to be as short as in intact piglets (5 min. In the rat, the half-life of pLH was also found to be very short (3–6 min and 123I-pLH was found to accumulate in high quantity in less than 10 min post injection at the level of kidneys but not in the liver. 123I-eCG didn't accumulate in any organ in the rats during the first hour, plasma concentrations of this gonadotropin being still elevated (80% at this time. Conclusion In both the porcine and rat species, the liver is not responsible for the rapid elimination of pLH from the circulation compared to eCG. Our scintigraphic experiments suggest that the very short circulatory half-life of LH is due to rapid renal trapping.

  9. Contraception. Slow train gathers speed.

    Science.gov (United States)

    Hampton, N; Kubba, A

    The otherwise slow pace of contraceptive research developments has recently quickened, with new products developed, more on the way, and encouraging new data emerging about existing methods. While the 1995 UK pill scare called attention to a differential in the risk of venous thromboembolism (VTE) between pills containing levonorgestrel or norethisterone and those containing desogestrel or gestodene, there is only an extremely small level of excess mortality attributable to third-generation progestogens, less than 2 per million women per year. Tentative evidence suggests that pills with less anti-estrogenic progestogens are neutral with regard to coronary artery disease. The pill remains extremely safe for healthy young women, although additional research with larger numbers of participants is warranted. Salient research findings are that the combined oral contraceptive pill may protect against colon cancer, the pill appears to offer no protection against bone fractures, new products contain less estrogen and have a shortened pill-free interval, a WHO paper showed no significant association between cardiovascular disease and the use of oral or injectable progestogens, a UK study showed no correlation between bone density and plasma estrogen concentrations among long-term users of depot medroxyprogesterone acetate, and a WHO controlled trial found a progestogen-only method of emergency contraception to be considerably more effective in preventing expected pregnancies than the Yuzpe regimen. The T 380 copper IUD provides very high protection against intrauterine and extrauterine pregnancies for 10 years and is now available in an improved inserting mechanism, the Mirena levonorgestrel-releasing IUD system is now licensed for 5 years, and the GyneFIX IUD implant is a frameless device fixed during insertion to the fundal myometrium.

  10. Local hybrid functionals: an assessment for thermochemical kinetics.

    Science.gov (United States)

    Kaupp, Martin; Bahmann, Hilke; Arbuznikov, Alexei V

    2007-11-21

    Local hybrid functionals with position-dependent exact-exchange admixture are a new class of exchange-correlation functionals in density functional theory that promise to advance the available accuracy in many areas of application. Local hybrids with different local mixing functions (LMFs) governing the position dependence are validated for the heats of formation of the extended G3/99 set, and for two sets of barriers of hydrogen-transfer and heavy-atom transfer reactions (HTBH38 and NHTBH38 databases). A simple local hybrid Lh-SVWN with only Slater and exact exchange plus local correlation and a one-parameter LMF, g(r)=b(tau(W)(r)tau(r)), performs best and provides overall mean absolute errors for thermochemistry and kinetics that are a significant improvement over standard state-of-the-art global hybrid functionals. In particular, this local hybrid functional does not suffer from the systematic deterioration that standard functionals exhibit for larger molecules. In contrast, local hybrids based on generalized gradient approximation exchange tend to give rise to nonintuitive LMFs, and no improved functionals have been obtained along this route. The LMF is a real-space function and thus can be analyzed in detail. We use, in particular, graphical analyses to rationalize the performance of different local hybrids for thermochemistry and reaction barriers.

  11. Temperature dependent LH1→RC energy transfer in purple bacteria Tch. tepidum with shiftable LH1-Qy band: A natural system to investigate thermally activated energy transfer in photosynthesis.

    Science.gov (United States)

    Ma, Fei; Yu, Long-Jiang; Wang-Otomo, Zheng-Yu; van Grondelle, Rienk

    2016-04-01

    The native LH1-RC complex of the purple bacterium Thermochromatium (Tch.) tepidum has an ultra-red LH1-Qy absorption at 915nm, which can shift to 893 and 882nm by means of chemical modifications. These unique complexes are a good natural system to investigate the thermally activated energy transfer process, with the donor energies different while the other factors (such as the acceptor energy, special pair at 890nm, and the distance/relative orientation between the donor and acceptor) remain the same. The native B915-RC, B893-RC and B882-RC complexes, as well as the LH1-RC complex of Rhodobacter (Rba.) sphaeroides were studied by temperature-dependent time-resolved absorption spectroscopy. The energy transfer time constants, kET(-1), are 65, 45, 46 and 45ps at room temperature while 225, 58, 85, 33ps at 77K for the B915-RC, B893-RC, B882-RC and Rba. sphaeroides LH1-RC, respectively. The dependences of kET on temperature have different trends. The reorganization energies are determined to be 70, 290, 200 and 45cm(-1), respectively, by fitting kET vs temperature using Marcus equation. The activation energies are 200, 60, 115 and 20cm(-1), respectively. The influences of the structure (the arrangement of the 32 BChl a molecules) on kET are discussed based on these results, to reveal how the B915-RC complex accomplishes its energy transfer function with a large uphill energy of 290cm(-1).

  12. Reciprocating Probe Measurements of L-H Transition in LHCD H-mode on EAST

    DEFF Research Database (Denmark)

    Peng, Liu; Guosheng, Xu; Huiqian, Wang

    2013-01-01

    only. Reciprocating Langmuir probe measurements at the outer midplane showed that the electron density ne and electron temperature Te in the scrape-off layer (SOL) were significantly reduced in the ELM-free phase, resulting in the increase of lower-hybrid wave (LHW) reflection. It was found...

  13. Kinetic investigation for slow combustion of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S. [Istanbul Technical Univ., Istanbul (Turkey). Dept. of Chemical Engineering, Faculty of Chemical and Metallurgical Engineering

    2006-07-01

    The renewed interest in biomass as a renewable, clean, and inexpensive fuel was discussed. Many different mechanisms take place simultaneously during biomass combustion and also during other thermal processes such as gasification, pyrolysis or carbonization. These mechanisms have a pronounced influence on the design and operation of thermal conversion processes. In addition, product yields and product distributions from the thermal processes are sensitive to the kinetic properties of biomass. In order to evaluate the combustion mechanisms and the combustion kinetics of biomass, the behavior of these constituents under combustion conditions were properly evaluated. In this study, combustion of biomass samples was carried out in a thermogravimetric analyzer by heating them from ambient to 1173 K with heating rates of 5 K/min and 10 K/min under dynamic dry air atmosphere of 40 mL/min. The biomass samples included olive refuse, sunflower seed shell, rapeseed, grape seed, and hybrid poplar. The purpose of the study was to examine the kinetic properties of biomass during slow combustion for the overall combustion process as well as for some definite temperature intervals at which different combustion mechanisms are present according to the type and complexity of biomass used. Derivative thermogravimetric analysis (DTG) curves were derived, and data obtained from these curves were used to compute the kinetic parameters such as activation energy, pre-exponential factor, and governing mechanisms for the combustion processes. The governing mechanisms for individual temperature intervals were examined along with the overall combustion process. The study showed that at lower temperature intervals, the combustion process was controlled primarily by the chemical reaction. At least 3 sequential mechanisms may occur at different temperature intervals during combustion of biomass. Activation energy and pre-exponential factors were determined for each temperature interval

  14. Enhanced four-wave mixing in graphene-silicon slow-light photonic crystal waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hao, E-mail: hz2299@columbia.edu, E-mail: tg2342@columbia.edu, E-mail: cww2104@columbia.edu [College of Electronic Information, Sichuan University, Chengdu 610064 (China); Optical Nanostructures Laboratory, Columbia University, New York, New York 10027 (United States); Gu, Tingyi, E-mail: hz2299@columbia.edu, E-mail: tg2342@columbia.edu, E-mail: cww2104@columbia.edu; McMillan, James F.; Wong, Chee Wei, E-mail: hz2299@columbia.edu, E-mail: tg2342@columbia.edu, E-mail: cww2104@columbia.edu [Optical Nanostructures Laboratory, Columbia University, New York, New York 10027 (United States); Petrone, Nicholas; Zande, Arend van der; Hone, James C. [Mechanical Engineering, Columbia University, New York, New York 10027 (United States); Yu, Mingbin; Lo, Guoqiang; Kwong, Dim-Lee [The Institute of Microelectronics, Singapore 117685 (Singapore); Feng, Guoying [College of Electronic Information, Sichuan University, Chengdu 610064 (China); Zhou, Shouhuan [College of Electronic Information, Sichuan University, Chengdu 610064 (China); North China Research Institute of Electro-Optics, Beijing 100015 (China)

    2014-09-01

    We demonstrate the enhanced four-wave mixing of monolayer graphene on slow-light silicon photonic crystal waveguides. 200-μm interaction length, a four-wave mixing conversion efficiency of −23 dB is achieved in the graphene-silicon slow-light hybrid, with an enhanced 3-dB conversion bandwidth of about 17 nm. Our measurements match well with nonlinear coupled-mode theory simulations based on the measured waveguide dispersion, and provide an effective way for all-optical signal processing in chip-scale integrated optics.

  15. Current generation by helicons and LH waves in modern tokamaks and reactors FNSF-AT, ITER and DEMO. Scenarios, modeling and antennae

    Energy Technology Data Exchange (ETDEWEB)

    Vdovin, V. [NRC Kurchatov Institute Tokamak Physics Institute, Moscow (Russian Federation)

    2014-02-12

    The Innovative concept and 3D full wave code modeling Off-axis current drive by RF waves in large scale tokamaks, reactors FNSF-AT, ITER and DEMO for steady state operation with high efficiency was proposed [1] to overcome problems well known for LH method [2]. The scheme uses the helicons radiation (fast magnetosonic waves at high (20–40) IC frequency harmonics) at frequencies of 500–1000 MHz, propagating in the outer regions of the plasmas with a rotational transform. It is expected that the current generated by Helicons will help to have regimes with negative magnetic shear and internal transport barrier to ensure stability at high normalized plasma pressure β{sub N} > 3 (the so-called Advanced scenarios) of interest for FNSF and the commercial reactor. Modeling with full wave three-dimensional codes PSTELION and STELEC2 showed flexible control of the current profile in the reactor plasmas of ITER, FNSF-AT and DEMO [2,3], using multiple frequencies, the positions of the antennae and toroidal waves slow down. Also presented are the results of simulations of current generation by helicons in tokamaks DIII-D, T-15MD and JT-60SA [3]. In DEMO and Power Plant antenna is strongly simplified, being some analoge of mirrors based ECRF launcher, as will be shown. For spherical tokamaks the Helicons excitation scheme does not provide efficient Off-axis CD profile flexibility due to strong coupling of helicons with O-mode, also through the boundary conditions in low aspect machines, and intrinsic large amount of trapped electrons, as is shown by STELION modeling for the NSTX tokamak. Brief history of Helicons experimental and modeling exploration in straight plasmas, tokamaks and tokamak based fusion Reactors projects is given, including planned joint DIII-D – Kurchatov Institute experiment on helicons CD [1].

  16. Current generation by helicons and LH waves in modern tokamaks and reactors FNSF-AT, ITER and DEMO. Scenarios, modeling and antennae

    Science.gov (United States)

    Vdovin, V.

    2014-02-01

    The Innovative concept and 3D full wave code modeling Off-axis current drive by RF waves in large scale tokamaks, reactors FNSF-AT, ITER and DEMO for steady state operation with high efficiency was proposed [1] to overcome problems well known for LH method [2]. The scheme uses the helicons radiation (fast magnetosonic waves at high (20-40) IC frequency harmonics) at frequencies of 500-1000 MHz, propagating in the outer regions of the plasmas with a rotational transform. It is expected that the current generated by Helicons will help to have regimes with negative magnetic shear and internal transport barrier to ensure stability at high normalized plasma pressure βN > 3 (the so-called Advanced scenarios) of interest for FNSF and the commercial reactor. Modeling with full wave three-dimensional codes PSTELION and STELEC2 showed flexible control of the current profile in the reactor plasmas of ITER, FNSF-AT and DEMO [2,3], using multiple frequencies, the positions of the antennae and toroidal waves slow down. Also presented are the results of simulations of current generation by helicons in tokamaks DIII-D, T-15MD and JT-60SA [3]. In DEMO and Power Plant antenna is strongly simplified, being some analoge of mirrors based ECRF launcher, as will be shown. For spherical tokamaks the Helicons excitation scheme does not provide efficient Off-axis CD profile flexibility due to strong coupling of helicons with O-mode, also through the boundary conditions in low aspect machines, and intrinsic large amount of trapped electrons, as is shown by STELION modeling for the NSTX tokamak. Brief history of Helicons experimental and modeling exploration in straight plasmas, tokamaks and tokamak based fusion Reactors projects is given, including planned joint DIII-D - Kurchatov Institute experiment on helicons CD [1].

  17. Slow Movement/Slow University: Critical Engagements. Introduction to the Thematic Section

    Directory of Open Access Journals (Sweden)

    Maggie O'Neill

    2014-09-01

    Full Text Available This thematic section emerged from two seminars that took place at Durham University in England in November 2013 and March 2014 on the possibilities for thinking through what a change movement towards slow might mean for the University. Slow movements have emerged in relation to a number of topics: Slow food, Citta slow and more recently, slow science. What motivated us in the seminars was to explore how far these movements could help us address the acceleration and intensification of work within our own and other universities, and indeed, what new learning, research, philosophies, practices, structures and governance might emerge. This editorial introduction presents the concept of the "slow university" and introduces our critical engagements with slow. The articles presented here interrogate the potentialities, challenges, problems and pitfalls of the slow university in an era of corporate culture and management rationality. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1403166

  18. Can Fast and Slow Intelligence Be Differentiated?

    Science.gov (United States)

    Partchev, Ivailo; De Boeck, Paul

    2012-01-01

    Responses to items from an intelligence test may be fast or slow. The research issue dealt with in this paper is whether the intelligence involved in fast correct responses differs in nature from the intelligence involved in slow correct responses. There are two questions related to this issue: 1. Are the processes involved different? 2. Are the…

  19. 49 CFR 236.813 - Speed, slow.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Speed, slow. 236.813 Section 236.813 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Speed, slow. A speed not exceeding 20 miles per hour....

  20. Tandem queue with server slow-down

    NARCIS (Netherlands)

    D.I. Miretskiy; W.R.W. Scheinhardt; M.R.H. Mandjes

    2007-01-01

    We study how rare events happen in the standard two-node tandem Jackson queue and in a generalization, the socalled slow-down network, see [2]. In the latter model the service rate of the first server depends on the number of jobs in the second queue: the first server slows down if the amount of job

  1. Slow-light pulses in moving media

    OpenAIRE

    Fiurasek, J.; Leonhardt, U.; Parentani, R.

    2000-01-01

    Slow light in moving media reaches a paradoxical regime when the flow speed of the medium approaches the group velocity of light. Pulses can penetrate a region where a counter-propagating flow exceeds the group velocity. When the counter-flow slows down pulses are reflected.

  2. Can fast and slow intelligence be differentiated?

    NARCIS (Netherlands)

    Partchev, I.; de Boeck, P.

    2012-01-01

    Responses to items from an intelligence test may be fast or slow. The research issue dealt with in this paper is whether the intelligence involved in fast correct responses differs in nature from the intelligence involved in slow correct responses. There are two questions related to this issue: 1.

  3. Age-related alterations in hypothalamic kisspeptin, neurokinin B, and dynorphin neurons and in pulsatile LH release in female and male rats.

    Science.gov (United States)

    Kunimura, Yuyu; Iwata, Kinuyo; Ishigami, Akihito; Ozawa, Hitoshi

    2017-02-01

    Pulsatile secretion of gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) decreases during aging. Kisspeptin (encoded by Kiss1) neurons in the arcuate nucleus coexpress neurokinin B (Tac3) and dynorphin (Pdyn) and are critical for regulating the GnRH/LH pulse. We therefore examined kisspeptin neurons by histochemistry and pulsatile LH release in rats aged 2-3 (Young), 12-13 (Young-Middle), 19-22 (Late-Middle), and 24-26 (Old) months. Total LH concentrations, sampled for 3 hours, decreased in both sexes with aging. In females, numbers of Tac3 and Pdyn neurons were significantly reduced in all aging rats, and numbers of Kiss1 neurons were significantly reduced in Late-Middle and Old rats. In males, numbers of all 3 neuron-types were significantly decreased in all aging rats. GnRH agonist induced LH release in all animals; however, the increased LH concentration in all aging rats was less than that in Young rats. These results suggest that expression of each gene in kisspeptin neurons may be controlled individually during aging, and that reduction of their expression or change in pituitary responsiveness may cause attenuated pulsatile LH secretion.

  4. KEA-144: Final Results of the Ground Operations Demonstration Unit for Liquid Hydrogen (GODU-LH2) Project

    Science.gov (United States)

    Notardonato, William; Fesmire, James; Swanger, Adam; Jumper, Kevin; Johnson, Wesley; Tomsik, Thomas

    2017-01-01

    GODU-LH2 system has successfully met all test objectives at the 33%, 67%, and 100% tank fill level. Complete control over the state of the fluid has been demonstrated using Integrated Refrigeration and Storage (IRAS). Almost any desired point along the H2saturation curve can essentially be "dialed in" and maintained indefinitely. System can also be used to produce densified hydrogen in large quantities to the triple point. Exploring multiple technology infusion paths. Studying implementation of IRAS technology into new LH2sphere for EM-2 at LC39B. Technical interchange also occurring with STMD, LSP, ULA, DoE, KIST, Kawasaki, Shell Oil, SpaceX, US Coast Guard, and Virgin Galactic.

  5. Single-molecule spectroscopy unmasks the lowest exciton state of the B850 assembly in LH2 from Rps. acidophila.

    Science.gov (United States)

    Kunz, Ralf; Timpmann, Kõu; Southall, June; Cogdell, Richard J; Freiberg, Arvi; Köhler, Jürgen

    2014-05-01

    We have recorded fluorescence-excitation and emission spectra from single LH2 complexes from Rhodopseudomonas (Rps.) acidophila. Both types of spectra show strong temporal spectral fluctuations that can be visualized as spectral diffusion plots. Comparison of the excitation and emission spectra reveals that for most of the complexes the lowest exciton transition is not observable in the excitation spectra due to the cutoff of the detection filter characteristics. However, from the spectral diffusion plots we have the full spectral and temporal information at hand and can select those complexes for which the excitation spectra are complete. Correlating the red most spectral feature of the excitation spectrum with the blue most spectral feature of the emission spectrum allows an unambiguous assignment of the lowest exciton state. Hence, application of fluorescence-excitation and emission spectroscopy on the same individual LH2 complex allows us to decipher spectral subtleties that are usually hidden in traditional ensemble spectroscopy.

  6. Slow Movements of Bio-Inspired Limbs

    Science.gov (United States)

    Babikian, Sarine; Valero-Cuevas, Francisco J.; Kanso, Eva

    2016-10-01

    Slow and accurate finger and limb movements are essential to daily activities, but the underlying mechanics is relatively unexplored. Here, we develop a mathematical framework to examine slow movements of tendon-driven limbs that are produced by modulating the tendons' stiffness parameters. Slow limb movements are driftless in the sense that movement stops when actuations stop. We demonstrate, in the context of a planar tendon-driven system representing a finger, that the control of stiffness suffices to produce stable and accurate limb postures and quasi-static (slow) transitions among them. We prove, however, that stable postures are achievable only when tendons are pretensioned, i.e., they cannot become slack. Our results further indicate that a non-smoothness in slow movements arises because the precision with which individual stiffnesses need to be altered changes substantially throughout the limb's motion.

  7. Connecting slow earthquakes to huge earthquakes.

    Science.gov (United States)

    Obara, Kazushige; Kato, Aitaro

    2016-07-15

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge earthquakes if the adjacent locked region is critically loaded. Careful and precise monitoring of slow earthquakes may provide new information on the likelihood of impending huge earthquakes.

  8. Connecting slow earthquakes to huge earthquakes

    Science.gov (United States)

    Obara, Kazushige; Kato, Aitaro

    2016-07-01

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge earthquakes if the adjacent locked region is critically loaded. Careful and precise monitoring of slow earthquakes may provide new information on the likelihood of impending huge earthquakes.

  9. Higher ghrelin and lower leptin secretion are associated with lower LH secretion in young amenorrheic athletes compared with eumenorrheic athletes and controls.

    Science.gov (United States)

    Ackerman, Kathryn E; Slusarz, Katherine; Guereca, Gabriela; Pierce, Lisa; Slattery, Meghan; Mendes, Nara; Herzog, David B; Misra, Madhusmita

    2012-04-01

    Amenorrhea is common in young athletes and is associated with low fat mass. However, hormonal factors that link decreased fat mass with altered gonadotropin pulsatility and amenorrhea are unclear. Low levels of leptin (an adipokine) and increased ghrelin (an orexigenic hormone that increases as fat mass decreases) impact gonadotropin pulsatility. Studies have not examined luteinizing hormone (LH) secretory dynamics in relation to leptin or ghrelin secretory dynamics in adolescent and young adult athletes. We hypothesized that 1) young amenorrheic athletes (AA) would have lower LH and leptin and higher ghrelin secretion than eumenorrheic athletes (EA) and nonathletes and 2) higher ghrelin and lower leptin would be associated with lower LH secretion. This was a cross-sectional study. We examined ghrelin and leptin secretory patterns (over 8 h, from 11 PM to 7 AM) in relation to LH secretory patterns in AA, EA, and nonathletes aged 14-21 yr. Ghrelin and leptin were assessed every 20 min and LH every 10 min. Groups did not differ for age, bone age, or BMI. However, fat mass was lower in AA than in EA and nonathletes. AA had lower LH and higher ghrelin pulsatile secretion and AUC than nonathletes and lower leptin pulsatile secretion and AUC than EA and nonathletes. Percent body fat was associated positively with LH and leptin secretion and inversely with ghrelin. In a regression model, ghrelin and leptin secretory parameters were associated independently with LH secretory parameters. We conclude that higher ghrelin and lower leptin secretion in AA related to lower fat mass may contribute to altered LH pulsatility and amenorrhea.

  10. Hybrid internet access

    Science.gov (United States)

    Arora, Vivek; Baras, John S.; Dillon, Douglas; Falk, Aaron; Suphasindhu, Narin

    1995-01-01

    Access to the Internet is either too slow (dial-up SLIP) or too expensive (switched 56 kbps, frame relay) for the home user or small enterprise. The Center for Satellite and Hybrid Communication Networks and Hughes Network Systems have collaborated using systems integration principles to develop a prototype of a low-cost hybrid (dial-up and satellite) newtork terminal which can deliver data from the Internet to the user at rates up to 160 kbps. An asymmetric TCP/IP connection is used breaking the network link into two physical channels: a terrestrial dial-up for carrying data from the terminal into the Internet and a receive-only satellite link carrying IP packets from the Internet to the user. With a goal of supporting bandwidth hungry Internet applications such as Mosaic, Gopher, and FTP, this system has been designed to support any Intel 80386/486 PC, any commercial TCP/IP package, any unmodified host on the Internet, and any of the routers, etc., within the Internet. The design exploits the following three observations: 1) satellites are able to offer high bandwidth connections to a large geographical area, 2) a receive-only VSAT is cheap to manufacture and easier to install than one which can also transmit, and 3) most computer users, especially those in a home environment, will want to consume much more information than they generate. IP encapsulation, or tunneling, issued to manipulate the TCP/IP protocols to route packets asymmetrically.

  11. Study on the L-H transition power threshold with RF heating and lithium-wall coating on EAST

    Science.gov (United States)

    Chen, L.; Xu, G. S.; Nielsen, A. H.; Gao, W.; Duan, Y. M.; Liu, H. Q.; Wang, L.; Li, M. H.; Wang, M.; Zhang, X. J.; Chen, R.; Wang, H. Q.; Sun, Z.; Ding, S. Y.; Yan, N.; Liu, S. C.; Shao, L. M.; Zhang, W.; Hu, G. H.; Li, J.; Zhang, L.; Wan, B. N.; the EAST Team

    2016-05-01

    The power threshold for low (L) to high (H) confinement mode transition achieved by radio-frequency (RF) heating and lithium-wall coating is investigated experimentally on EAST for two sets of walls: an all carbon wall (C) and molybdenum chamber and a carbon divertor (Mo/C). For both sets of walls, a minimum power threshold P thr of ~0.6 MW was found when the EAST operates in a double null (DN) divertor configuration with intensive lithium-wall coating. When operating in upper single null (USN) or lower single null (LSN), the power threshold depends on the ion  ∇B drift direction. The low density dependence of the L-H power threshold, namely an increase below a minimum density, was identified in the Mo/C wall for the first time. For the C wall only the single-step L-H transition with limited injection power is observed whereas also the so-called dithering L-H transition is observed in the Mo/C wall. The dithering behaves distinctively in a USN, DN and LSN configuration, suggesting the divertor pumping capability is an important ingredient in this transition since the internal cryopump is located underneath the lower divertor. Depending on the chosen divertor configuration, the power across the separatrix P loss increases with neutral density near the lower X-point in EAST with the Mo/C wall, consistent with previous results in the C wall (Xu et al 2011 Nucl. Fusion 51 072001). These findings suggest that the edge neutral density, the ion  ∇B drift as well as the divertor pumping capability play important roles in the L-H power threshold and transition behaviour.

  12. Path to Efficient Lower Hybrid Current Drive at High Density

    Science.gov (United States)

    Baek, S. G.; Bonoli, P. T.; Brunner, D.; Faust, I.; Labombard, B. L.; Parker, R. R.; Shiraiwa, S.; Wallace, G. M.; Wukitch, S.

    2015-11-01

    Recovery of lower hybrid current drive (LHCD) efficiency at high density was demonstrated on Alcator C-Mod by modifying the scrape-off layer (SOL) plasma. RF probe measurements around the C-Mod tokamak indicate that the LH wave amplitude at the high field side wall significantly attenuates with plasma density. This is interpreted as enhanced collisional loss due to the increase in the SOL density and width. By taking advantage of the narrower SOL width by doubling plasma current to 1.1 MA, it is found that the LH wave amplitude maintains its strength, and an effective current drive is extended to above 1x10e20 m-3. An order of magnitude increase in non-thermal Bremsstrahlung emission is consistent with ray-tracing results which take into account the change of SOL profiles with current. In the coming campaign, a further investigation on the role of the SOL plasma is planned by raising plasma current above 1.1 MA. This will be aided with newly developed RF magnetic loop antennas mounted on a radially movable probe head. This system is expected to intercept the LH resonance cone on the first pass, allowing us to measure radial profiles of both the wave amplitude and dominant parallel wavenumber in the SOL for the first time. These data will be compared with the GENRAY ray-tracing code. Work supported by USDoE awards DE-FC02-99ER54512.

  13. Demonstration of the Coexistence of Duplicated LH Receptors in Teleosts, and Their Origin in Ancestral Actinopterygians.

    Directory of Open Access Journals (Sweden)

    Gersende Maugars

    Full Text Available Pituitary gonadotropins, FSH and LH, control gonad activity in vertebrates, via binding to their respective receptors, FSHR and LHR, members of GPCR superfamily. Until recently, it was accepted that gnathostomes possess a single FSHR and a single LHR, encoded by fshr and lhcgr genes. We reinvestigated this question, focusing on vertebrate species of key-phylogenetical positions. Genome analyses supported the presence of a single fshr and a single lhcgr in chondrichthyans, and in sarcopterygians including mammals, birds, amphibians and coelacanth. In contrast, we identified a single fshr but two lhgcr in basal teleosts, the eels. We further showed the coexistence of duplicated lhgcr in other actinopterygians, including a non-teleost, the gar, and other teleosts, e.g. Mexican tetra, platyfish, or tilapia. Phylogeny and synteny analyses supported the existence in actinopterygians of two lhgcr paralogs (lhgcr1/ lhgcr2, which do not result from the teleost-specific whole-genome duplication (3R, but likely from a local gene duplication that occurred early in the actinopterygian lineage. Due to gene losses, there was no impact of 3R on the number of gonadotropin receptors in extant teleosts. Additional gene losses during teleost radiation, led to a single lhgcr (lhgcr1 or lhgcr2 in some species, e.g. medaka and zebrafish. Sequence comparison highlighted divergences in the extracellular and intracellular domains of the duplicated lhgcr, suggesting differential properties such as ligand binding and activation mechanisms. Comparison of tissue distribution in the European eel, revealed that fshr and both lhgcr transcripts are expressed in the ovary and testis, but are differentially expressed in non-gonadal tissues such as brain or eye. Differences in structure-activity relationships and tissue expression may have contributed as selective drives in the conservation of the duplicated lhgcr. This study revises the evolutionary scenario and nomenclature of

  14. Static and dynamic protein impact on electronic properties of light-harvesting complex LH2.

    Science.gov (United States)

    Zerlauskiene, O; Trinkunas, G; Gall, A; Robert, B; Urboniene, V; Valkunas, L

    2008-12-11

    A comparative analysis of the temperature dependence of the absorption spectra of the LH2 complexes from different species of photosynthetic bacteria, i.e., Rhodobacter sphaeroides, Rhodoblastus acidophilus, and Phaeospirillum molischianum, was performed in the temperature range from 4 to 300 K. Qualitatively, the temperature dependence is similar for all of the species studied. The spectral bandwidths of both B800 and B850 bands increases with temperature while the band positions shift in opposite directions: the B800 band shifts slightly to the red while the B850 band to the blue. These results were analyzed using the modified Redfield theory based on the exciton model. The main conclusion drawn from the analysis was that the spectral density function (SDF) is the main factor underlying the strength of the temperature dependence of the bandwidths for the B800 and B850 electronic transitions, while the bandwidths themselves are defined by the corresponding inhomogeneous distribution function (IDF). Slight variation of the slope of the temperature dependence of the bandwidths between species can be attributed to the changes of the values of the reorganization energies and characteristic frequencies determining the SDF. To explain the shift of the B850 band position with temperature, which is unusual for the conventional exciton model, a temperature dependence of the IDF must be postulated. This dependence can be achieved within the framework of the modified (dichotomous) exciton model. The slope of the temperature dependence of the B850 bandwidth is then defined by the value of the reorganization energy and by the difference between the transition energies of the dichotomous states of the pigment molecules. The equilibration factor between these dichotomous states mainly determines the temperature dependence of the peak shift.

  15. The safe removal of frozen air from the annulus of an LH2 storage tank

    Science.gov (United States)

    Krenn, A.; Starr, S.; Youngquist, R.; Nurge, M.; Sass, J.; Fesmire, J.; Cariker, C.; Bhattacharya, A.

    2015-12-01

    Large Liquid Hydrogen (LH2) storage tanks are vital infrastructure for NASA. Eventually, air may leak into the evacuated and perlite filled annular region of these tanks. Although the vacuum level is monitored in this region, the extremely cold temperature causes all but the helium and neon constituents of air to freeze. A small, often unnoticeable pressure rise is the result. As the leak persists, the quantity of frozen air increases, as does the thermal conductivity of the insulation system. Consequently, a notable increase in commodity boil-off is often the first indicator of an air leak. Severe damage can result from normal draining of the tank. The warming air will sublimate which will cause a pressure rise in the annulus. When the pressure increases above the triple point, the frozen air will begin to melt and migrate downward. Collection of liquid air on the carbon steel outer shell may chill it below its ductility range, resulting in fracture. In order to avoid a structural failure, as described above, a method for the safe removal of frozen air is needed. A thermal model of the storage tank has been created using SINDA/FLUINT modelling software. Experimental work is progressing in an attempt to characterize the thermal conductivity of a perlite/frozen nitrogen mixture. A statistical mechanics model is being developed in parallel for comparison to experimental work. The thermal model will be updated using the experimental/statistical mechanical data, and used to simulate potential removal scenarios. This paper will address methodologies and analysis techniques for evaluation of two proposed air removal methods.

  16. The Safe Removal of Frozen Air from the Annulus of an LH2 Storage Tank

    Science.gov (United States)

    Krenn, A.; Starr, S.; Youngquist, R.; Nurge, M.; Sass, J.; Fesmire, J.; Cariker, C.; Bhattacharya, A.

    2015-01-01

    Large Liquid Hydrogen (LH2) storage tanks are vital infrastructure for NASA. Eventually, air may leak into the evacuated and perlite filled annular region of these tanks. Although the vacuum level is monitored in this region, the extremely cold temperature causes all but the helium and neon constituents of air to freeze. A small, often unnoticeable pressure rise is the result. As the leak persists, the quantity of frozen air increases, as does the thermal conductivity of the insulation system. Consequently, a notable increase in commodity boil-off is often the first indicator of an air leak. Severe damage can result from normal draining of the tank. The warming air will sublimate which will cause a pressure rise in the annulus. When the pressure increases above the triple point, the frozen air will begin to melt and migrate downward. Collection of liquid air on the carbon steel outer shell may chill it below its ductility range, resulting in fracture. In order to avoid a structural failure, as described above, a method for the safe removal of frozen air is needed. A thermal model of the storage tank has been created using SINDA/FLUINT modeling software. Experimental work is progressing in an attempt to characterize the thermal conductivity of a perlite/frozen nitrogen mixture. A statistical mechanics model is being developed in parallel for comparison to experimental work. The thermal model will be updated using the experimental/statistical mechanical data, and used to simulate potential removal scenarios. This paper will address methodologies and analysis techniques for evaluation of two proposed air removal methods.

  17. Axisymmetric oscillations at L-H transitions in JET: M-mode

    Science.gov (United States)

    Solano, Emilia R.; Vianello, N.; Delabie, E.; Hillesheim, J. C.; Buratti, P.; Réfy, D.; Balboa, I.; Boboc, A.; Coelho, R.; Sieglin, B.; Silburn, S.; Drewelow, P.; Devaux, S.; Dodt, D.; Figueiredo, A.; Frassinetti, L.; Marsen, S.; Meneses, L.; Maggi, C. F.; Morris, J.; Gerasimov, S.; Baruzzo, M.; Stamp, M.; Grist, D.; Nunes, I.; Rimini, F.; Schmuck, S.; Lupelli, I.; Silva, C.; contributors, JET

    2017-02-01

    L to H transition studies at JET have revealed an n  =  0, m  =  1 magnetic oscillation starting immediately at the L to H transition (called M-mode for brevity). While the magnetic oscillation is present a weak ELM-less H-mode regime is obtained, with a clear increase of density and a weak electron temperature pedestal. It is an intermediate state between L and H-mode. In ICRH heated plasmas or low density NBI plasmas the magnetic mode and the pedestal can remain steady (with small oscillations) for the duration of the heating phase, of order 10 s or more. The axisymmetric magnetic oscillation has period ~0.5-2 ms, and poloidal mode number m  =  1: it looks like a pedestal localised up/down oscillation, although it is clearly a natural oscillation of the plasma, not driven by the position control system. Electron cyclotron emission, interferometry, reflectometry and fast Li beam measurements locate the mode in the pedestal region. D α , fast infrared camera and Langmuir probe measurements show that the mode modulates heat and particle fluxes to the target. The mode frequency appears to scale with the poloidal Alfvén velocity, and not with sound speed (i.e. it is not a geodesic acoustic mode). A heuristic model is proposed for the frequency scaling of the mode. We discuss the relationship between the M-mode and other related observations near the L-H transition.

  18. Evidence for high-pressure-induced rupture of hydrogen bonds in LH2 photosynthetic antenna pigment-protein complexes

    Energy Technology Data Exchange (ETDEWEB)

    Kangur, L; Leiger, K; Freiberg, A [Institute of Physics, University of Tartu, Riia 142, Tartu 51014 (Estonia)

    2008-07-15

    The bacteriochlorophyll a-containing LH2 light harvesting complex is an integral membrane protein that catalyzes the photosynthetic process in purple photosynthetic bacteria. The LH2 complexes from Rhodobacter sphaeroides show characteristic strong absorbance at 800 and 850 nm due to the bacteriochlorophyll a molecules confined in two separate areas of the protein. Using these cofactors as intrinsic probes to monitor changes in membrane protein structure, we investigate the response to high hydrostatic pressure up to 2.1 GPa of LH2 complexes embedded into natural membrane environment or extracted with detergent. We demonstrate that high pressure does induce significant alterations to the tertiary structure of the protein in proximity of the protein-bound bacteriochlorophyll a molecules, including breakage of the hydrogen bond they are involved in. The membrane-embedded complexes appear more resilient to damaging effects of the compression than the complexes extracted into detergent environment. This difference has tentatively been explained by more compact structure of the membrane-embedded complexes.

  19. Dependence of the L-H transition on X-point geometry and divertor recycling on NSTX

    Science.gov (United States)

    Battaglia, D. J.; Chang, C. S.; Kaye, S. M.; Kim, K.; Ku, S.; Maingi, R.; Bell, R. E.; Diallo, A.; Gerhardt, S.; LeBlanc, B. P.; Menard, J.; Podesta, M.; the NSTX Team

    2013-11-01

    The edge electron (Te) and ion temperature (Ti) at the time of the L-H transition increase when the X-point radius (RX) is reduced to a high-triangularity shape while maintaining constant edge density. Consequently the L-H power threshold (PLH) is larger for the high-triangularity shape. This supports the prediction that a single-particle loss hole, whose properties are strongly linked to RX and Ti, influences the edge radial electric field (Er) and Er × B flow-shearing rate available for turbulence suppression. Simulations using XGC0, a full-f drift-kinetic neoclassical code, indicate that maintaining a constant Er × B flow-shearing rate does require a larger heat flux and edge Ti as RX decreases. NSTX also observes a decrease in PLH when the divertor recycling is decreased using lithium coatings. However, the edge Te and Ti at the L-H transition appear independent of the divertor recycling for a constant shape. XGC0 calculations demonstrate that more heat flux is needed to maintain the edge Ti and the Er × B flow-shearing rate as the contribution of divertor recycling to the overall neutral fuelling rate increases.

  20. Enhanced light-harvesting capacity by micellar assembly of free accessory chromophores and LH1-like antennas.

    Science.gov (United States)

    Harris, Michelle A; Sahin, Tuba; Jiang, Jianbing; Vairaprakash, Pothiappan; Parkes-Loach, Pamela S; Niedzwiedzki, Dariusz M; Kirmaier, Christine; Loach, Paul A; Bocian, David F; Holten, Dewey; Lindsey, Jonathan S

    2014-01-01

    Biohybrid light-harvesting antennas are an emerging platform technology with versatile tailorability for solar-energy conversion. These systems combine the proven peptide scaffold unit utilized for light harvesting by purple photosynthetic bacteria with attached synthetic chromophores to extend solar coverage beyond that of the natural systems. Herein, synthetic unattached chromophores are employed that partition into the organized milieu (e.g. detergent micelles) that house the LH1-like biohybrid architectures. The synthetic chromophores include a hydrophobic boron-dipyrrin dye (A1) and an amphiphilic bacteriochlorin (A2), which transfer energy with reasonable efficiency to the bacteriochlorophyll acceptor array (B875) of the LH1-like cyclic oligomers. The energy-transfer efficiencies are markedly increased upon covalent attachment of a bacteriochlorin (B1 or B2) to the peptide scaffold, where the latter likely acts as an energy-transfer relay site for the (potentially diffusing) free chromophores. The efficiencies are consistent with a Förster (through-space) mechanism for energy transfer. The overall energy-transfer efficiency from the free chromophores via the relay to the target site can approach those obtained previously by relay-assisted energy transfer from chromophores attached at distant sites on the peptides. Thus, the use of free accessory chromophores affords a simple design to enhance the overall light-harvesting capacity of biohybrid LH1-like architectures.

  1. The Effects of Trifluralin on LH, FSH and Testosterone Hormone Levels and Testis Histological Changes in Adult Rats

    Directory of Open Access Journals (Sweden)

    Mehrdad Shariati

    2008-01-01

    Full Text Available Background: Trifluralin is a herbicide and used in agriculture widely. It enters plants throughdeveloping roots and stops plant cells from division and elongation (meristemic inhibitor.Extensive application of trifluralin to control annual grasses and broadleaf weeds in agriculture,horticulture and horn garden, leads to environmental pollution and its entrance into the food chaincould have determined effects on human and other species. In this research the effects of trifluralinon reproductive parameters of the male rats including serum luteinizing hormone (LH, folliclestimulatinghormone (FSH, testosterone levels, and changes in testicular tissue and body weightwere investigated.Materials and Methods: For this purpose male rats were randomly divided in 5 groups, to includecontrol, sham (received normal saline as a solvent, and three experimental groups which received500, 1000 and 2000 mg/kg oral trifluralin respectively. After 16 days, body and testis weight weremeasured and blood samples were taken from heart and used for measurement of LH, FSH andtestosterone levels. To evaluate histological changes, testes were removed and weighed and, afterobtaining tissue section, stained by HE.Results: Serum testosterone, FSH, and LH levels showed significant decrease in experimentalgroups (p<0.05. There was significant decrease in the number of germinal and somatic cells intestis in experimental groups. There was also a significant decrease in body and testis weight inexperimental groups.Conclusion: It can be concluded that oral administration of trifluralin could decrease gonadotropinsand testosterone hormone levels and also this herbicide could have hazardous effects on testistissue.

  2. Effect of the mutation of carotenoids on the dynamics of energy transfer in light- harvesting complexes (LH2) from Rhodobacter sphaeroides 601 at room temperature

    Institute of Scientific and Technical Information of China (English)

    Liu Wei-Min; Liu Yuan; Liu Rang-Jun; Yan Yong-Li; Guo Li-Jun; Xu Chun-He; Qian Shi-Xiong

    2006-01-01

    Energy transfers in two kinds of peripheral light-harvesting complexes (LH2) of Rhodobacter sphaeroides (RS) 601 are studied by using femtosecond pump-probe spectroscopy with tunable laser wavelength at room temperature. These two complexes are native LH2 (RS601) and green carotenoid mutated LH2 (GM309). The obtained results demonstrate that, compared with spheroidenes with ten conjugated double bonds in native RS601, carotenoid in GM309 containing neurosporenes with nine conjugated double bonds can lead to a reduction in energy transfer rate in the B800-to-B850 band and the disturbance in the energy relaxation processes within the excitonic B850 band.

  3. Synchrotron Small-Angle X-Ray Scattering Investigation on Integral Membrane Protein Light-Harvesting Complex LH2 from Photosynthetic Bacterium Rhodopseudomonas Acidophila

    Institute of Scientific and Technical Information of China (English)

    DU Lu-Chao; WENG Yu-Xiang; HONG Xin-Guo; XIAN Ding-Chang; Kobayashi Katsumi

    2006-01-01

    @@ Structures of membrane protein in solution are different from that in crystal phase. We present the primary results of small angle x-ray scattering (SAXS) resolved topological structures of a light harvesting antenna membrane protein complex LH2 from photosynthetic bacteria Rhodopseudomonas acidophila in detergent solution for the first time. Our results show that the elliptical shape of the LH2 complex in solution clearly deviates from its circular structure in crystal phase determined by x-ray diffraction. This result provides an insight into the structure and function interplay in LH2.

  4. The open, the closed, and the empty: time-resolved fluorescence spectroscopy and computational analysis of RC-LH1 complexes from Rhodopseudomonas palustris.

    Science.gov (United States)

    Beyer, Sebastian R; Müller, Lars; Southall, June; Cogdell, Richard J; Ullmann, G Matthias; Köhler, Jürgen

    2015-01-29

    We studied the time-resolved fluorescence of isolated RC-LH1 complexes from Rhodopseudomonas palustris as a function of the photon fluence and the repetition rate of the excitation laser. Both parameters were varied systematically over 3 orders of magnitude. On the basis of a microstate description we developed a quantitative model for RC-LH1 and obtained very good agreement between experiments and elaborate simulations based on a global master equation approach. The model allows us to predict the relative population of RC-LH1 complexes with the special pair in the neutral state or in the oxidized state P(+) and those complexes that lack a reaction center.

  5. Análise de eventos hidrológicos extremos, usando-se a distribuição GEV e momentos LH Analysis of extreme hydrological events using GEV distribution and LH moments

    Directory of Open Access Journals (Sweden)

    Manoel M. F. de Queiroz

    2006-06-01

    Full Text Available A distribuição de probabilidade generalizada de valores extremos (GEV, tem facilitado muitas aplicações em hidrologia, utilizada na modelação de eventos extremos naturais. Estudos sobre o assunto mostram que estimadores de máxima verossimilhança dos parâmetros da GEV são instáveis em pequenas amostras, podendo fornecer valores absurdos do parâmetro de forma, quando então são recomendados estimadores de momentos LH, baseados na combinação linear de estatísticas de altas ordens, introduzidas para caracterizar a parte mais alta da distribuição e os valores extremos dos dados; contudo, não se dispõe de programas computacionais para PC, que modelem eventos extremos via momentos LH. Objetivou-se, com este trabalho, apresentar a modelação de eventos hidrológicos extremos através da distribuição GEV, utilizando-se momentos LH para estimar seus parâmetros e o teste estatístico proposto por Wang (1998 para verificação da qualidade dos ajustes desenvolvidos no ambiente Matlab. Como resultados, são apresentados as estimativas dos parâmetros da GEV, os valores das taxas de momentos LH: coeficientes de variação, assimetria e curtose, e os valores do teste de qualidade de ajuste, em aplicações com dados de vazão de rios do Paraná.The generalized extreme-value (GEV distribution has facilitated many applications in hydrology, used to model a wide variety of natural extreme events. Previous studies show that small-sample maximum-likelihood estimators parameters are unstable and demonstrates that absurd values of the GEV shape parameter can be generated. It is recommended that LH moments estimators, based on linear combinations of higher-order statistics, should be introduced for characterizing the upper part of distributions and larger events in data. However, there have been no computer packages for PC that model extreme events by LH moments. The objective of this paper was to present the modeling of hydrological extreme

  6. Slow light Mach-Zehnder fiber interferometer

    Institute of Scientific and Technical Information of China (English)

    Yundong Zhang; Jinfang Wang; Xuenan Zhang; Hao Wu; Yuanxue Cai; Jing Zhang; Ping Yuan

    2012-01-01

    A slow light structure Mach-Zehnder fiber interferometer is theoretically demonstrated.The sensitivity of the interferometer is significantly enhanced by the dispersion of the slow light structure.The numerical results show that the sensitivity enhancement factor varies with the coupling coefficient and reaches its maximum under critical coupling conditions.Interferometers have been investigated in relation to their applications in fields such as metrology[1],optical sensing[2],optical communication[3,4],quantum information processing[5],and biomedical engineering[6].A number of schemes have been proposed to improve the performance of interferometers[7],such as using photonic crystal structures to minimize the size of on-chip devices[8],utilizing the dispersive property of semiconductor to enhance the spectral sensitivity of interferometers[9,10],utilizing slow light medium to enhance the resolution of Fourier transform interferometer[11],exploiting fast light medium or slow light structure to increase the rotation sensitivity of a Sagnac interferometer[12,13],enhancing the transmittance of the Mach-Zehnder interferometer (MZI) in the slow light region by gratings[14],and using liquid crystal light valve to derive high sensitivity interferometers[15].%A slow light structure Mach-Zehnder fiber interferometer is theoretically demonstrated. The sensitivity of the interferometer is significantly enhanced by the dispersion of the slow light structure. The numerical results show that the sensitivity enhancement factor varies with the coupling coefficient and reaches its maximum under critical coupling conditions.

  7. KEK-IMSS Slow Positron Facility

    Energy Technology Data Exchange (ETDEWEB)

    Hyodo, T; Wada, K; Yagishita, A; Kosuge, T; Saito, Y; Kurihara, T; Kikuchi, T; Shirakawa, A; Sanami, T; Ikeda, M; Ohsawa, S; Kakihara, K; Shidara, T, E-mail: toshio.hyodo@kek.jp [High Energy Accelerator Research Organization (KEK) 1-1 Oho, Tsukuba, Ibaraki, 305-0801 (Japan)

    2011-12-01

    The Slow Positron Facility at the Institute of Material Structure Science (IMSS) of High Energy Accelerator Research Organization (KEK) is a user dedicated facility with an energy tunable (0.1 - 35 keV) slow positron beam produced by a dedicated 55MeV linac. The present beam line branches have been used for the positronium time-of-flight (Ps-TOF) measurements, the transmission positron microscope (TPM) and the photo-detachment of Ps negative ions (Ps{sup -}). During the year 2010, a reflection high-energy positron diffraction (RHEPD) measurement station is going to be installed. The slow positron generator (converter/ moderator) system will be modified to get a higher slow positron intensity, and a new user-friendly beam line power-supply control and vacuum monitoring system is being developed. Another plan for this year is the transfer of a {sup 22}Na-based slow positron beam from RIKEN. This machine will be used for the continuous slow positron beam applications and for the orientation training of those who are interested in beginning researches with a slow positron beam.

  8. KEK-IMSS Slow Positron Facility

    Science.gov (United States)

    Hyodo, T.; Wada, K.; Yagishita, A.; Kosuge, T.; Saito, Y.; Kurihara, T.; Kikuchi, T.; Shirakawa, A.; Sanami, T.; Ikeda, M.; Ohsawa, S.; Kakihara, K.; Shidara, T.

    2011-12-01

    The Slow Positron Facility at the Institute of Material Structure Science (IMSS) of High Energy Accelerator Research Organization (KEK) is a user dedicated facility with an energy tunable (0.1 - 35 keV) slow positron beam produced by a dedicated 55MeV linac. The present beam line branches have been used for the positronium time-of-flight (Ps-TOF) measurements, the transmission positron microscope (TPM) and the photo-detachment of Ps negative ions (Ps-). During the year 2010, a reflection high-energy positron diffraction (RHEPD) measurement station is going to be installed. The slow positron generator (converter/ moderator) system will be modified to get a higher slow positron intensity, and a new user-friendly beam line power-supply control and vacuum monitoring system is being developed. Another plan for this year is the transfer of a 22Na-based slow positron beam from RIKEN. This machine will be used for the continuous slow positron beam applications and for the orientation training of those who are interested in beginning researches with a slow positron beam.

  9. Generation and evolution of interplanetary slow shocks

    Directory of Open Access Journals (Sweden)

    C.-C. Wu

    Full Text Available It is well known that most MHD shocks observed within 1 AU are MHD fast shocks. Only a very limited number of MHD slow shocks are observed within 1 AU. In order to understand why there are only a few MHD slow shocks observed within 1 AU, we use a one-dimensional, time-dependent MHD code with an adaptive grid to study the generation and evolution of interplanetary slow shocks (ISS in the solar wind. Results show that a negative, nearly square-wave perturbation will generate a pair of slow shocks (a forward and a reverse slow shock. In addition, the forward and the reverse slow shocks can pass through each other without destroying their characteristics, but the propagating speeds for both shocks are decreased. A positive, square-wave perturbation will generate both slow and fast shocks. When a forward slow shock (FSS propagates behind a forward fast shock (FFS, the former experiences a decreasing Mach number. In addition, the FSS always disappears within a distance of 150R (where R is one solar radius from the Sun when there is a forward fast shock (with Mach number ≥1.7 propagating in front of the FSS. In all tests that we have performed, we have not discovered that the FSS (or reverse slow shock evolves into a FFS (or reverse fast shock. Thus, we do not confirm the FSS-FFS evolution as suggested by Whang (1987.

  10. Slow light vortices in periodic waveguides

    DEFF Research Database (Denmark)

    Sukhorukov, Andrey A.; Ha, Sangwoo; Desyatnikov, Anton S.

    2009-01-01

    We reveal that the reduction of the group velocity of light in periodic waveguides is generically associated with the presence of vortex energy flows. We show that the energy flows are gradually frozen for slow-light at the Brillouin zone edge, whereas vortices persist for slow-light states havin...... non-vanishing phase velocity inside the Brillouin zone. We also demonstrate that presence of vortices can be linked to the absence of slow-light at the zone edge, and present calculations illustrating these general results....

  11. Slow-light vortices in periodic waveguides

    DEFF Research Database (Denmark)

    Sukhorukov, Andrey A.; Ha, Sangwoo; Desyatnikov, Anton S.

    2009-01-01

    We reveal that the reduction of the group velocity of light in periodic waveguides is generically associated with the presence of vortex energy flows. We show that the energy flows are gradually frozen for slow-light at the Brillouin zone edge, whereas vortices persist for slow-light states havin...... non-vanishing phase velocity inside the Brillouin zone. We also demonstrate that presence of vortices can be linked to the absence of slow-light at the zone edge, and present calculations illustrating these general results....

  12. Polarized (3) He Spin Filters for Slow Neutron Physics.

    Science.gov (United States)

    Gentile, T R; Chen, W C; Jones, G L; Babcock, E; Walker, T G

    2005-01-01

    Polarized (3)He spin filters are needed for a variety of experiments with slow neutrons. Their demonstrated utility for highly accurate determination of neutron polarization are critical to the next generation of betadecay correlation coefficient measurements. In addition, they are broadband devices that can polarize large area and high divergence neutron beams with little gamma-ray background, and allow for an additional spin-flip for systematic tests. These attributes are relevant to all neutron sources, but are particularly well-matched to time of flight analysis at spallation sources. There are several issues in the practical use of (3)He spin filters for slow neutron physics. Besides the essential goal of maximizing the (3)He polarization, we also seek to decrease the constraints on cell lifetimes and magnetic field homogeneity. In addition, cells with highly uniform gas thickness are required to produce the spatially uniform neutron polarization needed for beta-decay correlation coefficient experiments. We are currently employing spin-exchange (SE) and metastability-exchange (ME) optical pumping to polarize (3)He, but will focus on SE. We will discuss the recent demonstration of 75 % (3)He polarization, temperature-dependent relaxation mechanism of unknown origin, cell development, spectrally narrowed lasers, and hybrid spin-exchange optical pumping.

  13. Slow gamma rhythms in CA3 are entrained by slow gamma activity in the dentate gyrus.

    Science.gov (United States)

    Hsiao, Yi-Tse; Zheng, Chenguang; Colgin, Laura Lee

    2016-12-01

    In hippocampal area CA1, slow (∼25-55 Hz) and fast (∼60-100 Hz) gamma rhythms are coupled with different CA1 afferents. CA1 slow gamma is coupled to inputs from CA3, and CA1 fast gamma is coupled to inputs from the medial entorhinal cortex (Colgin LL, Denninger T, Fyhn M, Hafting T, Bonnevie T, Jensen O, Moser MB, Moser EI. Nature 462: 353-357, 2009). CA3 gives rise to highly divergent associational projections, and it is possible that reverberating activity in these connections generates slow gamma rhythms in the hippocampus. However, hippocampal gamma is maximal upstream of CA3, in the dentate gyrus (DG) region (Bragin A, Jando G, Nadasdy Z, Hetke J, Wise K, Buzsaki G. J Neurosci 15: 47-60, 1995). Thus it is possible that slow gamma in CA3 is driven by inputs from DG, yet few studies have examined slow and fast gamma rhythms in DG recordings. Here we investigated slow and fast gamma rhythms in paired recordings from DG and CA3 in freely moving rats to determine whether slow and fast gamma rhythms in CA3 are entrained by DG. We found that slow gamma rhythms, as opposed to fast gamma rhythms, were particularly prominent in DG. We investigated directional causal influences between DG and CA3 by Granger causality analysis and found that DG slow gamma influences CA3 slow gamma. Moreover, DG place cell spikes were strongly phase-locked to CA3 slow gamma rhythms, suggesting that DG excitatory projections to CA3 may underlie this directional influence. These results indicate that slow gamma rhythms do not originate in CA3 but rather slow gamma activity upstream in DG entrains slow gamma rhythms in CA3. Copyright © 2016 the American Physiological Society.

  14. New inroads on the Physics of Upper Hybrid Turbulence

    Science.gov (United States)

    Papadopoulos, Konstantinos Dennis; Najmi, Amir; Eliasson, Bengt

    2016-07-01

    The physics associated with excitation of Upper Hybrid (UH) turbulence, including the observed high and low frequency wave spectra and the resultant plasma heating and acceleration is still covered with many puzzles that have yet to be understood within the context of traditional theories. A set of new computer simulations using a Vlasov code revealed several critical plasma wave features associated with driving waves in the upper hybrid resonance. In addition to the well-known excitation of a lower hybrid wave and an upper hybrid sideband shifted by the Lower Hybrid (LH) frequency usually seen in Stimulated Electromagnetic Emission (SEE) observations in ionospheric HF heating experiments the following major features were apparent: 1. Broadening of the wavenumber spectral region at the at the UH frequency 2. Excitation of all Bernstein modes associated with cyclotron frequency harmonics both below and above the UH frequency 3. The electron heating, in the form of bulk heating (close to a Dryvestein distribution) is due to a part of the wave-number spectrum associated with the first Bernstein mode, although its wave intensity is more than 20 dB lower than the intensity of the UH branch 4. An exception to the previous feature occurs when the UH frequency is close to an harmonic of the electron cyclotron frequency (ω_{UH} ≈ n Ω_e), when the first UH lower sideband equals a multiple of the cyclotron frequency (ω_{UH} - ω_{LH} ≈ n Ω_e). In this case the electron heating is due the downshifted UH waves, it is much stronger than in the non-resonant case and it is in the form of the high-energy tail. The implications of the new theory of the UH turbulence in the interpretation of observations in space plasmas and wave particle interactions will be discussed. Acknowledgment: The authors acknowledge discussions with their colleagues G. Milikh, S. Surma, Xi Shao and R. Sagdeev. Work supported by AFOSR MURI grant FA95501410019.

  15. THE ESTROGENIC AND ANTIANDROGENIC PESTICIDE METHOXYCHLOR ALTERS THE REPRODUCTIVE TRACT AND BEHAVIOR WITHOUT AFFECTING PITUITARY SIZE OR LH AND PROLACTIN SECRETION IN MALE RATS

    Science.gov (United States)

    The estrogenic and antiandrogenic pesticide methoxychlor alters the reproductive tract and behavior without affecting pituitary size or LH and prolactin secretion in male rats.Gray LE Jr, Ostby J, Cooper RL, Kelce WR.Endocrinology Branch, United States Environment...

  16. Experimental demonstration of spinor slow light

    CERN Document Server

    Lee, Meng-Jung; Lee, Chin-Yuan; Kudriasov, Viaceslav; Chang, Kao-Fang; Cho, Hung-Wen; Juzeliunas, Gediminas; Yu, Ite A

    2014-01-01

    Over the last decade the developments of slow, stored and stationary light based on the electromagnetically induced transparency effect have attracted a great deal of attention, stimulated by potential applications such as low-light-level nonlinear optics and quantum information manipulation. The previous experiments all dealt with the single-component slow light. Here we report the first experimental demonstration of two-component or spinor slow light using a double tripod (DT) atom-light coupling scheme which involves two atomic ground state coherences. We observe the neutrino-type oscillations between the two slow light components controlled by the two-photon detuning. We show that the DT scheme for the light storage behaves like the two outcomes of a Mach-Zehnder interferometer enabling high precision measurements of the frequency detuning. Finally, we experimentally demonstrate a possible application of the DT scheme as quantum memory/rotator for the two-color qubits.

  17. Depression Can Slow Hospital Patients' Recovery

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_166427.html Depression Can Slow Hospital Patients' Recovery: Study Screening for ... 9, 2017 FRIDAY, June 9, 2017 (HealthDay News) -- Depression affects about one-third of hospital patients and ...

  18. Systematic Design of Slow Light Waveguides

    DEFF Research Database (Denmark)

    Wang, Fengwen

    Light can propagate much slower in photonic crystal waveguides and plasmonic waveguides than in vacuum. Slow light propagation in waveguides shows broad prospects in the terabit communication systems. However, it causes severe signal distortions and displays large propagation loss. Moreover...... two different parameterizations. Detailed comparisons show that the bandwidth of slow light propagation can be significantly enhanced by allowing irregular geometries in the waveguides. To mitigate the propagation loss due to scattering in the photonic crystal waveg- uides, an optimization problem...... is formulated to minimize the average propagation loss of the designed modes. The presented approach is employed to design a free-topology slow light waveguide. Numerical result illustrates that slow light propagation in the optimized waveguide displays significantly suppressed propagation loss while keeping...

  19. Slow living and the green economy

    Directory of Open Access Journals (Sweden)

    Diana-Eugenia Ioncică

    2016-05-01

    Full Text Available The current paper explores the relationship between some relatively new concepts in the field of economics – slow living, slow food, slow writing and the green economy. The goal of the paper is twofold – discussing the possibilities opened by these exciting new concepts, in terms of an increase in the quality of life combined with an environmentally sustainable lifestyle, as well as ascertaining what the concepts may entail in the context in which the effects of the recent economic crisis may make green and slow living seem like a distant dream. It is this holistic view that we shall attempt to enlarge upon in the paper, with the avowed purpose of weighing out the possibilities presented in the complicated, crisis-fraught global context.

  20. Pre- and postoperative status of gonadotropins (FSH and LH) and inhibin-B in relation to testicular histopathology at orchiopexy in infant boys with unilateral undescended testes

    DEFF Research Database (Denmark)

    Thorup, Jørgen Mogens; Clasen-Linde, Erik; Thorup, Sebastian Cortes

    2015-01-01

    had preoperatively elevated serum levels of both LH 0.5-2.3 IU/l (mean: 1.0 IU/l) and FSH 1.3-2.2 IU/l (mean: 1.6 IU/l). Eight of these patients normalized both LH and FSH serum values postoperatively. None of the 4 boys with impaired inhibin-B level that did not normalize after surgery had elevated...

  1. Human LH and hCG stimulate differently the early signalling pathways but result in equal testosterone synthesis in mouse Leydig cells in vitro.

    Science.gov (United States)

    Riccetti, Laura; De Pascali, Francesco; Gilioli, Lisa; Potì, Francesco; Giva, Lavinia Beatrice; Marino, Marco; Tagliavini, Simonetta; Trenti, Tommaso; Fanelli, Flaminia; Mezzullo, Marco; Pagotto, Uberto; Simoni, Manuela; Casarini, Livio

    2017-01-05

    Human luteinizing hormone (LH) and chorionic gonadotropin (hCG) are glycoprotein hormones regulating development and reproductive functions by acting on the same receptor (LHCGR). We compared the LH and hCG activity in gonadal cells from male mouse in vitro, i.e. primary Leydig cells, which is a common tool used for gonadotropin bioassay. Murine Leydig cells are naturally expressing the murine LH receptor (mLhr), which binds human LH/hCG. Cultured Leydig cells were treated by increasing doses of recombinant LH and hCG, and cell signaling, gene expression and steroid synthesis were evaluated. We found that hCG is about 10-fold more potent than LH in cAMP recruitment, and slightly but significantly more potent on cAMP-dependent Erk1/2 phosphorylation. However, no significant differences occur between LH and hCG treatments, measured as activation of downstream signals, such as Creb phosphorylation, Stard1 gene expression and testosterone synthesis. These data demonstrate that the responses to human LH/hCG are only quantitatively and not qualitatively different in murine cells, at least in terms of cAMP and Erk1/2 activation, and equal in activating downstream steroidogenic events. This is at odds with what we previously described in human primary granulosa cells, where LHCGR mediates a different pattern of signaling cascades, depending on the natural ligand. This finding is relevant for gonadotropin quantification used in the official pharmacopoeia, which are based on murine, in vivo bioassay and rely on the evaluation of long-term, testosterone-dependent effects mediated by rodent receptor.

  2. Lower Hybrid Wave Current Drive Efficiency on the HT-7 Tokamak

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhong-Yong; WAN Bao-Nian; SHI Yue-Jiang; HU Li-Qun; XU Han-Dong; LI Guo-Chao

    2005-01-01

    @@ Lower hybrid (LH) wave current drive efficiency on our HT-7 tokamak has been investigated based on the hot electrical conductivity theory.The interaction of the residual toroidal electric field with fast electrons has been included in the determination of current drive efficiency.The LH wave power scan was performed in the plasma parameter ranges of Ip = 50-156kA, (n)e = 0.5 × 1019-1.6 × 1019 m-3, PLH = 50-350kW.The current drive efficiency is derived to be about 0.1 × 1019-0.4 × 1019 Am-2W-1 on the HT-7 tokamak, which depends on the electron density and the LH wave phase velocity.At the electron density of about 1.5 × 1019 m-3, with the LH wave parallel refraction index peaked at 1.8, the highest current drive efficiency was obtained.A more generally normalized method is introduced to analyse the experimental data, which combines all the data in one curve.The normalized parameters are independent of the plasma parameters.

  3. Bio-equivalent doses of recombinant HCG and recombinant LH during ovarian stimulation result in similar oestradiol output: a randomized controlled study.

    Science.gov (United States)

    Alsbjerg, Birgit; Elbaek, Helle Olesen; Laursen, Rita Jakubcionyte; Povlsen, Betina Boel; Haahr, Thor; Yding Andersen, Claus; Humaidan, Peter

    2017-08-01

    In nature, HCG is secreted by the implanting embryo from peri-implantation and onwards. In contrast, LH is mandatory for steroidogenesis and follicular development during the follicular phase, working in synergy with FSH. Moreover, LH is mandatory for the function of the corpus luteum. Although LH and HCG bind to the same receptor, significant molecular, structural and functional differences exist, inducing differences in bioactivity. This randomized controlled study compared the effect of recombinant FSH stimulation combined with daily either micro-dose recombinant HCG or recombinant LH supplementation in a 1:1 bioactivity ratio from day 1 of stimulation in a long gonadotrophin releasing hormone agonist down regulation protocol. A total of 100 patients from a public clinic completed the study. The primary end-point was the oestradiol level on the day of ovulation trigger and the median oestradiol level in the HCG supplemented group was 8662 pmol/l versus 9203 pmol/l in the recombinant LH supplemented group; therefore, no significant difference was found. Moreover, no differences were observed in the number of oocytes retrieved or in the live birth rate. We conclude that recombinant HCG and recombinant LH are equally effective in boosting oestradiol synthesis during ovarian stimulation when used in a 1:1 bioactivity ratio. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  4. Hybrid microelectronic technology

    Science.gov (United States)

    Moran, P.

    Various areas of hybrid microelectronic technology are discussed. The topics addressed include: basic thick film processing, thick film pastes and substrates, add-on components and attachment methods, thin film processing, and design of thick film hybrid circuits. Also considered are: packaging hybrid circuits, automating the production of hybrid circuits, application of hybrid techniques, customer's view of hybrid technology, and quality control and assurance in hybrid circuit production.

  5. Mouse Oocytes Enable LH-Induced Maturation of the Cumulus-Oocyte Complex via Promoting EGF Receptor-Dependent Signaling

    Science.gov (United States)

    Su, You-Qiang; Sugiura, Koji; Li, Qinglei; Wigglesworth, Karen; Matzuk, Martin M.; Eppig, John J.

    2010-01-01

    LH triggers the maturation of the cumulus-oocyte complex (COC), which is followed by ovulation. These ovarian follicular responses to LH are mediated by epidermal growth factor (EGF)-like growth factors produced by granulosa cells and require the participation of oocyte-derived paracrine factors. However, it is not clear how oocytes coordinate with the EGF receptor (EGFR) signaling to achieve COC maturation. The aim of the present study was to test the hypothesis that oocytes promote the expression of EGFR by cumulus cells, thus enabling them to respond to the LH-induced EGF-like peptides. Egfr mRNA and protein expression were dramatically reduced in cumulus cells of mutant mice deficient in the production of the oocyte-derived paracrine factors growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15). Moreover, microsurgical removal of oocytes from wild-type COCs dramatically reduced expression of Egfr mRNA and protein, and these levels were restored by either coculture with oocytes or treatment with recombinant GDF9 or GDF9 plus recombinant BMP15. Blocking Sma- and Mad-related protein (SMAD)2/3 phosphorylation in vitro inhibited Egfr expression in wild-type COCs and in GDF9-treated wild-type cumulus cells, and conditional deletion of Smad2 and Smad3 genes in granulosa cells in vivo resulted in the reduction of Egfr mRNA in cumulus cells. These results indicate that oocytes promote expression of Egfr in cumulus cells, and a SMAD2/3-dependent pathway is involved in this process. At least two oocyte-derived growth factors, GDF9 and BMP15, are required for EGFR expression by cumulus cells. PMID:20382892

  6. Hybrid lipids increase nanoscale fluctuation lifetimes in mixed membranes

    Science.gov (United States)

    Palmieri, Benoit; Safran, Samuel A.

    2013-09-01

    A recently proposed ternary mixture model is used to predict fluctuation domain lifetimes in the one phase region. The membrane is made of saturated, unsaturated, and hybrid lipids that have one saturated and one unsaturated hydrocarbon chain. The hybrid lipid is a natural linactant which can reduce the packing incompatibility between saturated and unsaturated lipids. The fluctuation lifetimes are predicted as a function of the hybrid lipid fraction and the fluctuation domain size. These lifetimes can be increased by up to three orders of magnitude compared to the case of no hybrids. With hybrid, small length scale fluctuations have sizable amplitudes even close to the critical temperature and, hence, benefit from enhanced critical slowing down. The increase in lifetime is particularly important for nanometer scale fluctuation domains where the hybrid orientation and the other lipids composition are highly coupled.

  7. Single fixed-time artificial insemination in gilts and weaned sows using pLH at estrus onset administered through vulvar submucosal route.

    Science.gov (United States)

    Ulguim, R R; Fontana, D L; Bernardi, M L; Wentz, I; Bortolozzo, F P

    2016-09-01

    This study evaluated the use of a single fixed-time artificial insemination (FTAI) in gilts and weaned sows using 2.5 mg of porcine luteinizing hormone (pLH) administered through vulvar submucosal route, at the onset of estrus. In experiment 1 (Exp.1), 318 pubertal gilts were assigned to two groups: control-G-no hormonal application and artificial inseminations (AIs) at 12, 36, and 60 hours after the onset of estrus if they were still in standing estrus; and FTAI-G-use of pLH at the onset of estrus and a single FTAI 12 hours later. In experiment 2 (Exp. 2), 309 weaned sows were assigned to three groups: Control-S-no hormone application and AIs at 0, 24, and 48 hours after the onset of estrus if they were still in standing estrus; FTAI-NH-no hormone application and a single FTAI at 24 hours after the onset of estrus, and FTAI-pLH-use of pLH at the onset of estrus and a single FTAI 24 hours later. Transabdominal real time B-mode ultrasonography was performed to determine whether the insemination had been performed within 24 hours before ovulation, considered as the optimal interval. In Exp. 1, ultrasound evaluation (12-hour intervals) was carried out to determine the interval between the onset of estrus and ovulation. In both experiments, 2 × 10(9) sperm cells in 80 mL were used to perform cervical and postcervical deposition of semen in gilts and sows, respectively. Compared with control-G, FTAI-G gilts had shorter (P pLH: 88.0%) and TPB (Control-S: 12.8; FTAI-NH: 12.7, and FTAI-pLH: 12.0 piglets) among treatments. The presence of semen backflow reduced (P pLH and FTAI-NH sows. In the FTAI-pLH, a single insemination performed too late relative to ovulation reduced the AFR (P pLH applied at the vulvar submucosa at the onset of estrus advances the ovulation in gilts, but a single FTAI performed 12 hours later reduces the farrowing rate. A single FTAI performed at 24 hours after the onset of estrus in weaned sows does not affect their reproductive

  8. [Accreditation of automated complete blood count by the LH750 Analyzer (Beckman Coulter) in Georges Pompidou Hospital (Paris, France)].

    Science.gov (United States)

    Robinet, Sylvain; Lemaire, Pierre; Louis, Gauthier; Vieillefond, Vincent; Daigneau, Yolande; Gaillaud, Emilie; Vincent, Béatrice; Fischer, Anne-Marie; Siguret, Virginie

    2013-01-01

    Preliminary evaluation of quantitative clinical laboratory measurements is a prerequisite for the accreditation of clinical laboratories, according to the French Committee of Accreditation guidelines following the European reference Standard EN ISO 15189. Numerous papers have been published regarding biochemistry and immunology. However, data are lacking for automated complete blood count accreditation. We report here our experience at Hôpital européen Georges Pompidou hematology laboratory and present the performance characteristics of two mirrored LH750 Beckman-Coulter analysers, including precision, accuracy and uncertainty of measurement.

  9. Bio-equivalent doses of recombinant HCG and recombinant LH during ovarian stimulation result in similar oestradiol output

    DEFF Research Database (Denmark)

    Alsbjerg, Birgit; Elbaek, Helle Olesen; Laursen, Rita Jakubcionyte

    2017-01-01

    and HCG bind to the same receptor, significant molecular, structural and functional differences exist, inducing differences in bioactivity. This randomized controlled study compared the effect of recombinant FSH stimulation combined with daily either micro-dose recombinant HCG or recombinant LH...... supplementation in a 1:1 bioactivity ratio from day 1 of stimulation in a long gonadotrophin releasing hormone agonist down regulation protocol. A total of 100 patients from a public clinic completed the study. The primary end-point was the oestradiol level on the day of ovulation trigger and the median...

  10. Hybrid nonlinear model of the angular vestibulo-ocular reflex.

    Science.gov (United States)

    Ranjbaran, Mina; Galiana, Henrietta L

    2013-01-01

    A hybrid nonlinear bilateral model for the horizontal angular vestibulo-ocular reflex (AVOR) is presented in this paper. The model relies on known interconnections between saccadic burst circuits in the brainstem and ocular premotor areas in the vestibular nuclei during slow and fast phase intervals. A viable switching strategy for the timing of nystagmus events is proposed. Simulations show that this hybrid model replicates AVOR nystagmus patterns that are observed in experimentally recorded data.

  11. Topological Origins of the Slow Solar Wind

    Science.gov (United States)

    Antiochos, S.

    2008-12-01

    Although the slow solar wind has been studied for decades with both in situ and remote sensing observations, its origin is still a matter of intense debate. In the standard quasi-steady model, the slow wind is postulated to originate near coronal hole boundaries that define topologically well-behaved separatrices between open and closed field regions. In the interchange model, on the other hand, the slow wind is postulated to originate on open flux that is dynamically diffusing throughout the seemingly closed-field corona. We argue in favor of the quasi-steady scenario and propose that the slow wind is due to two effects: First, the open-closed boundary is highly complex due to the complexity of the photospheric flux distribution. Second, this boundary is continuously driven by the transport of magnetic helicity from the closed field region into the open. The implications of this model for the structure and dynamics of the corona and slow wind are discussed, and observational tests of the model are presented. This work has been supported, in part, by the NASA LWS, HTP, and SR&T programs.

  12. Global Network of Slow Solar Wind

    Science.gov (United States)

    Crooker, N. U.; Antiochos, S. K.; Zhao, X.; Neugebauer, M.

    2012-01-01

    The streamer belt region surrounding the heliospheric current sheet (HCS) is generally treated as the primary or sole source of the slow solar wind. Synoptic maps of solar wind speed predicted by the Wang-Sheeley-Arge model during selected periods of solar cycle 23, however, show many areas of slow wind displaced from the streamer belt. These areas commonly have the form of an arc that is connected to the streamer belt at both ends. The arcs mark the boundaries between fields emanating from different coronal holes of the same polarity and thus trace the paths of belts of pseudostreamers, i.e., unipolar streamers that form over double arcades and lack current sheets. The arc pattern is consistent with the predicted topological mapping of the narrow open corridor or singular separator line that must connect the holes and, thus, consistent with the separatrix-web model of the slow solar wind. Near solar maximum, pseudostreamer belts stray far from the HCS-associated streamer belt and, together with it, form a global-wide web of slow wind. Recognition of pseudostreamer belts as prominent sources of slow wind provides a new template for understanding solar wind stream structure, especially near solar maximum.

  13. Human gamma oscillations during slow wave sleep.

    Directory of Open Access Journals (Sweden)

    Mario Valderrama

    Full Text Available Neocortical local field potentials have shown that gamma oscillations occur spontaneously during slow-wave sleep (SWS. At the macroscopic EEG level in the human brain, no evidences were reported so far. In this study, by using simultaneous scalp and intracranial EEG recordings in 20 epileptic subjects, we examined gamma oscillations in cerebral cortex during SWS. We report that gamma oscillations in low (30-50 Hz and high (60-120 Hz frequency bands recurrently emerged in all investigated regions and their amplitudes coincided with specific phases of the cortical slow wave. In most of the cases, multiple oscillatory bursts in different frequency bands from 30 to 120 Hz were correlated with positive peaks of scalp slow waves ("IN-phase" pattern, confirming previous animal findings. In addition, we report another gamma pattern that appears preferentially during the negative phase of the slow wave ("ANTI-phase" pattern. This new pattern presented dominant peaks in the high gamma range and was preferentially expressed in the temporal cortex. Finally, we found that the spatial coherence between cortical sites exhibiting gamma activities was local and fell off quickly when computed between distant sites. Overall, these results provide the first human evidences that gamma oscillations can be observed in macroscopic EEG recordings during sleep. They support the concept that these high-frequency activities might be associated with phasic increases of neural activity during slow oscillations. Such patterned activity in the sleeping brain could play a role in off-line processing of cortical networks.

  14. Magnon Inflation: Slow Roll with Steep Potentials

    CERN Document Server

    Adshead, Peter; Burgess, C P; Hayman, Peter; Patil, Subodh P

    2016-01-01

    We find multi-scalar effective field theories (EFTs) that can achieve a slow inflationary roll despite having a scalar potential that does not satisfy the usual slow-roll condition (d V)^2 << V^2/Mp^2. They evade the usual slow-roll conditions on $V$ because their kinetic energies are dominated by single-derivative terms rather than the usual two-derivative terms. Single derivatives dominate during slow roll and so do not require a breakdown of the usual derivative expansion that underpins calculational control in much of cosmology. The presence of such terms requires some sort of UV Lorentz-symmetry breaking during inflation (besides the usual cosmological breaking). Chromo-natural inflation provides an example of a UV theory that can generate the multi-field single-derivative terms we consider, and we argue that the EFT we find indeed captures the slow-roll conditions for the background evolution for Chromo-natural inflation. We also show that our EFT can be understood as a multi-field generalization ...

  15. Slow wave propagation in soft adhesive interfaces.

    Science.gov (United States)

    Viswanathan, Koushik; Sundaram, Narayan K; Chandrasekar, Srinivasan

    2016-11-16

    Stick-slip in sliding of soft adhesive surfaces has long been associated with the propagation of Schallamach waves, a type of slow surface wave. Recently it was demonstrated using in situ experiments that two other kinds of slow waves-separation pulses and slip pulses-also mediate stick-slip (Viswanathan et al., Soft Matter, 2016, 12, 5265-5275). While separation pulses, like Schallamach waves, involve local interface detachment, slip pulses are moving stress fronts with no detachment. Here, we present a theoretical analysis of the propagation of these three waves in a linear elastodynamics framework. Different boundary conditions apply depending on whether or not local interface detachment occurs. It is shown that the interface dynamics accompanying slow waves is governed by a system of integral equations. Closed-form analytical expressions are obtained for the interfacial pressure, shear stress, displacements and velocities. Separation pulses and Schallamach waves emerge naturally as wave solutions of the integral equations, with oppositely oriented directions of propagation. Wave propagation is found to be stable in the stress regime where linearized elasticity is a physically valid approximation. Interestingly, the analysis reveals that slow traveling wave solutions are not possible in a Coulomb friction framework for slip pulses. The theory provides a unified picture of stick-slip dynamics and slow wave propagation in adhesive contacts, consistent with experimental observations.

  16. Magnon inflation: slow roll with steep potentials

    Energy Technology Data Exchange (ETDEWEB)

    Adshead, Peter [Department of Physics, University of Illinois at Urbana-Champaign,Urbana, IL 61801 (United States); Blas, Diego [Theoretical Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); Burgess, C.P.; Hayman, Peter [Physics & Astronomy, McMaster University,Hamilton, ON, L8S 4M1 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Patil, Subodh P. [Department of Theoretical Physics, University of Geneva,24 Quai Ansermet, Geneva, CH-1211 (Switzerland)

    2016-11-04

    We find multi-scalar effective field theories (EFTs) that can achieve a slow inflationary roll despite having a scalar potential that does not satisfy G{sup ab}∂{sub a}V∂{sub b}V≪V{sup 2}/M{sub p}{sup 2} (where G{sub ab} is the target-space metric). They evade the usual slow-roll conditions on V because their kinetic energies are dominated by single-derivative terms rather than the usual two-derivative terms. Single derivatives dominate during slow roll and so do not require a breakdown of the usual derivative expansion that underpins calculational control in much of cosmology. The presence of such terms requires some sort of UV Lorentz-symmetry breaking during inflation (besides the usual cosmological breaking). Chromo-natural inflation provides one particular example of a UV theory that can generate the multi-field single-derivative terms we consider, and we argue that the EFT we find indeed captures the slow-roll conditions for its background evolution. We also show that our EFT can be understood as a multi-field generalization of the single-field Cuscuton models. The multi-field case introduces a new feature, however: the scalar kinetic terms define a target-space 2-form, F{sub ab}, whose antisymmetry gives new ways for slow roll to be achieved.

  17. Immunodetection of Luteinizing Hormone (LH, Follicle-Stimulating Hormone (FSH, Thyroid Stimulating Hormone (TSH and Prolactin (PRL in Brachionus calyciflorus (Rotifera: Monogononta

    Directory of Open Access Journals (Sweden)

    Jesús Alvarado-Flores

    2009-12-01

    Full Text Available The endocrine system controls and coordinates behavioral, biochemical, and physiological processes through signal mechanisms using neuropeptides or products of neurosecretory cells. Among invertebrates, this system is poorly studied in rotifers, in which estrogens and androgens significantly affect sexual reproduction. This is the first report of the presence of the Luteinizing Hormone (LH, Follicle-Stimulating Hormone (FSH, Thyroid Stimulating Hormone (TSH and Prolactin (PRL in rotifers. Analyses included the avidin-biotin-peroxidase complex method with primary antibodies LH (Anti-Rat LH serum for RIA, PRL (Anti-Rat PRL serum for RIA, FSH (Anti-Rat FSH serum for RIA and TSH (Anti-Rat TSH serum for RIA. These hormones were found in females, males and parthenogenetic and sexual eggs of the freshwater Brachionus calyciflorus. The immunoreactivity of FSH, LH, TSH and PRL in females was observed in: ovaries, cerebrum, mastax, stomach, lorica, and the stomach gland. However, in males LH was observed only at the trochal disk and cerebrum. The hormones FSH, TSH and PRL, were observed in testicles, contractil vesicles, and cementary gland of males. Regarding amictic or parthenogenetic eggs, the hormones LH, FSH, TSH, and PRL were located mainly in the micromeres, and the staining in the macromeres was weak. On the other hand, in the mictic or sexual eggs the inner shell is stained for the hormones PRL and LH, opposite to the staining of FSH and TSH, located mainly in the embryo. In general, immuno-reactivity was observed in areas important for the reproductive, excretory, digestive and developmental processes. Rev. Biol. Trop. 57 (4: 1049-1058. Epub 2009 December 01.Se logró detectar la presencia de las hormonas: Hormona Luteinizante (LH, Hormona Folículo Estimulante (FSH, Hormona Estimulante de la Tiroides (TSH y Prolactina (PRL en Brachionus calyciflorus siendo el primer reporte de la presencia de dichas hormonas en rotíferos. Estas hormonas fueron

  18. Hybrid Gear

    Science.gov (United States)

    Handschuh, Robert F. (Inventor); Roberts, Gary D. (Inventor)

    2016-01-01

    A hybrid gear consisting of metallic outer rim with gear teeth and metallic hub in combination with a composite lay up between the shaft interface (hub) and gear tooth rim is described. The composite lay-up lightens the gear member while having similar torque carrying capability and it attenuates the impact loading driven noise/vibration that is typical in gear systems. The gear has the same operational capability with respect to shaft speed, torque, and temperature as an all-metallic gear as used in aerospace gear design.

  19. Hybrid Qualifications

    DEFF Research Database (Denmark)

    has turned out as a major focus of European education and training policies and certainly is a crucial principle underlying the European Qualifications Framework (EQF). In this context, «hybrid qualifications» (HQ) may be seen as an interesting approach to tackle these challenges as they serve «two...... masters», i.e. by producing skills for the labour market and enabling individuals to progress more or less directly to higher education. The specific focus of this book is placed on conditions, structures and processes which help to combine VET with qualifications leading into higher education...

  20. Evaluation of a new approach for the estimation of the time of the LH surge in dairy cows using vaginal temperature and electrodeless conductivity measurements.

    Science.gov (United States)

    Fisher, A D; Morton, R; Dempsey, J M A; Henshall, J M; Hill, J R

    2008-10-15

    The objective of the study was to test the effectiveness of a new type of conductivity sensor, along with vaginal temperature, at identifying the LH peak associated with estrus in dairy cows. Twelve mature non-lactating Holstein-Friesian cows had their estrous cycles synchronized on two occasions, and then data were collected for the following spontaneous cycles. An indwelling electrodeless plastic-coated toroidal conductivity sensor, which also recorded temperature, was placed in the vagina throughout the cycle. Blood samples were collected for LH measurement, and ultrasound scanning used to confirm ovulation. Although there was a relationship between vaginal mucus conductivity measured by the toroidal sensor and the timing of the LH surge, it was not sufficiently robust in individual cows to be able to identify the time of the LH surge. The mean increase in vaginal temperature at estrus was 0.48 degrees C. An algorithm was developed which used the detected individual cow temperature peak to test the relationship with the LH peak. In 16 out of 21 cases where ovulation was confirmed and data existed, the estimated individual peak was within 4h of the LH surge, in three cases it was +/-6h, and in two instances it was early. In conclusion, the temperature algorithm was able to identify the time of the LH surge and thus predict time of ovulation in a way that would allow effective AI, although this result needs to be tested in lactating cows. However, the toroidal conductivity sensing method was not able to produce data of sufficient quality to develop a predictive relationship in individual cows.

  1. Developmental Programming: Prenatal and Postnatal Androgen Antagonist and Insulin Sensitizer Interventions Prevent Advancement of Puberty and Improve LH Surge Dynamics in Prenatal Testosterone-Treated Sheep.

    Science.gov (United States)

    Padmanabhan, Vasantha; Veiga-Lopez, Almudena; Herkimer, Carol; Abi Salloum, Bachir; Moeller, Jacob; Beckett, Evan; Sreedharan, Rohit

    2015-07-01

    Prenatal T excess induces maternal hyperinsulinemia, early puberty, and reproductive/metabolic defects in the female similar to those seen in women with polycystic ovary syndrome. This study addressed the organizational/activational role of androgens and insulin in programming pubertal advancement and periovulatory LH surge defects. Treatment groups included the following: 1) control; 2) prenatal T; 3) prenatal T plus prenatal androgen antagonist, flutamide; 4) prenatal T plus prenatal insulin sensitizer, rosiglitazone; 5) prenatal T and postnatal flutamide; 6) prenatal T and postnatal rosiglitazone; and 7) prenatal T and postnatal metformin. Prenatal treatments spanned 30-90 days of gestation and postnatal treatments began at approximately 8 weeks of age and continued throughout. Blood samples were taken twice weekly, beginning at approximately 12 weeks of age to time puberty. Two-hour samples after the synchronization with prostaglandin F2α were taken for 120 hours to characterize LH surge dynamics at 7 and 19 months of age. Prenatal T females entered puberty earlier than controls, and all interventions prevented this advancement. Prenatal T reduced the percentage of animals having LH surge, and females that presented LH surge exhibited delayed timing and dampened amplitude of the LH surge. Prenatal androgen antagonist, but not other interventions, restored LH surges without normalizing the timing of the surge. Normalization of pubertal timing with prenatal/postnatal androgen antagonist and insulin sensitizer interventions suggests that pubertal advancement is programmed by androgenic actions of T involving insulin as a mediary. Restoration of LH surges by cotreatment with androgen antagonist supports androgenic programming at the organizational level.

  2. Universality of slow decorrelation in KPZ growth

    CERN Document Server

    Corwin, I; Peche, S

    2010-01-01

    We demonstrate that, under minimal hypothesis, a wide class of growth models diplays a phenomenon known as slow decorrelation, where along certain characteristic directions the range of correlation for fluctuations of the growth surface height is much longer than other directions. We apply this result to certain models known to be in the Kardar-Parisi-Zhang (KPZ) universality class in 1+1 dimension for which the necessary hypothesis holds. These models are the totally asymmetric simple exclusion process (TASEP), last passage percolation (LPP), and the polynuclear growth (PNG) model. Utilizing the slow decorrelation of fluctuations in these models we are able to extend known fluctuation limit process results away from the fixed curves on which they were proved, to general space-time curves. Using the monotonicity of the basic coupling we additionally prove that the partially asymmetric simple exclusion process (PASEP) displays slow decorrelation.

  3. Optical slowing of calcium monofluoride molecules

    Science.gov (United States)

    Ravi, Aakash; Chae, Eunmi; Hemmerling, Boerge; Anderegg, Loic; Augenbraun, Benjamin; Drayna, Garrett; Hutzler, Nicholas; Collopy, Alejandra; Wu, Yewei; Ding, Shiqian; Ye, Jun; Ketterle, Wolfgang; Doyle, John

    2016-05-01

    We report white-light slowing of calcium monofluoride molecules. A single main laser (606 nm) plus two additional vibrational repump lasers (628 nm) are employed. The slowing lasers are spectrally broadened to address the molecules' velocity spread and hyperfine splittings. We use a background-free two-photon fluorescence detection scheme to make high signal-to-noise measurements of our molecular beam's longitudinal velocity distribution. This method is applied to slow CaF produced by a two-stage cryogenic buffer gas beam source by > 30 m/s to near the capture velocity of a molecular magneto-optical trap (MOT). Due to the presence of magnetic dark states which inhibit optical cycling, we will use an AC-MOT. We characterize the performance of this AC-MOT used in the trapping of Li and Yb.

  4. Improved confinement in ELM-suppressed high-density H-modes at the ITER field via modification of the plasma boundary with Lower Hybrid RF

    Science.gov (United States)

    Terry, J. L.

    2014-10-01

    Injecting Lower Hybrid (LH) power into Alcator C-Mod's high-density H-mode plasmas has enhanced global confinement by increasing pedestal temperature gradients, modifying edge rotation, and decreasing edge and SOL turbulence. These new experiments indicate that edge LHRF can be used as a tool to increase confinement via direct modification of boundary quantities. Ray-tracing modeling and accessibility calculations for the LH waves indicate that the LH waves do not penetrate to regions inside the top of the pedestal and are not driving current in these plasmas; instead the LH power modifies the boundary conditions. When moderate amounts of LH power (PLH/Ptot = 20%) are applied to high-density EDA H-modes (neo = 3.5×1020 m-3) , we observe the following effects: edge/SOL fluctuation power decreases by roughly an order of magnitude; pedestal temperature gradients are increased; global energy confinement time and H-factor increase by 30-40% (H98 from 0.7 to 1.0); co-current core and pedestal rotation velocities increase; power to the (outer) divertor target increases promptly with an increment that is roughly 1/2 of the injected LH power, qualitatively consistent with the inaccessibility of the LH waves; and the central frequency of the edge-localized Quasi-Coherent Mode down-shifts and becomes much more coherent. These H-mode confinement improvements brought about by the edge LHRF are the result of changes in the pedestal (e.g. changes in rotation/shear and increased pedestal temperature gradients), with no substantial change in peaking of core density or temperature profiles. There is not perfect correlation with edge turbulence suppression, indicating that the turbulence decrease may be a necessary, but not sufficient, condition for the pedestal and confinement improvements. Supported by US DoE Awards DE-FC02-99ER54512 and DE-AC02-09CH11466.

  5. Synchronized ion acceleration by ultraintense slow light

    CERN Document Server

    Brantov, A V; Kovalev, V F; Bychenkov, V Yu

    2015-01-01

    An effective scheme of synchronized laser-triggered ion acceleration and the corresponding theoretical model are proposed for a slow light pulse of relativistic intensity, which penetrates into a near-critical-density plasma, strongly slows, and then increases its group velocity during propagation within a target. The 3D PIC simulations confirm this concept for proton acceleration by a femtosecond petawatt-class laser pulse experiencing relativistic self-focusing, quantify the characteristics of the generated protons, and demonstrate a significant increase of their energy compared with the proton energy generated from optimized ultrathin solid dense foils.

  6. Ultrafast Faraday Rotation of Slow Light

    Science.gov (United States)

    Musorin, A. I.; Sharipova, M. I.; Dolgova, T. V.; Inoue, M.; Fedyanin, A. A.

    2016-08-01

    The active control of optical signals in the time domain is what science and technology demand in fast all-optical information processing. Nanostructured materials can modify the group velocity and slow the light down, as the artificial light dispersion emerges. We observe the ultrafast temporal behavior of the Faraday rotation within a single femtosecond laser pulse under conditions of slow light in a one-dimensional magnetophotonic crystal. The Faraday effect changes by 20% over the time of 150 fs. This might be applicable to the fast control of light in high-capacity photonic devices.

  7. Slow crack growth in spinel in water

    Science.gov (United States)

    Schwantes, S.; Elber, W.

    1983-01-01

    Magnesium aluminate spinel was tested in a water environment at room temperature to establish its slow crack-growth behavior. Ring specimens with artificial flaws on the outside surface were loaded hydraulically on the inside surface. The time to failure was measured. Various precracking techniques were evaluated and multiple precracks were used to minimize the scatter in the static fatigue tests. Statistical analysis techniques were developed to determine the strength and crack velocities for a single flaw. Slow crack-growth rupture was observed at stress intensities as low as 70 percent of K sub c. A strengthening effect was observed in specimens that had survived long-time static fatigue tests.

  8. Geodynamic environments of ultra-slow spreading

    Science.gov (United States)

    Kokhan, Andrey; Dubinin, Evgeny

    2015-04-01

    Ultra-slow spreading is clearly distinguished as an outstanding type of crustal accretion by recent studies. Spreading ridges with ultra-slow velocities of extension are studied rather well. But ultra-slow spreading is characteristic feature of not only spreading ridges, it can be observed also on convergent and transform plate boundaries. Ultra-slow spreading is observed now or could have been observed in the past in the following geodynamic environments on divergent plate boundaries: 1. On spreading ridges with ultra-slow spreading, both modern (f.e. Gakkel, South-West Indian, Aden spreading center) and ceased (Labrador spreading center, Aegir ridge); 2. During transition from continental rifting to early stages of oceanic spreading (all spreading ridges during incipient stages of their formation); 3. During incipient stages of formation of spreading ridges on oceanic crust as a result of ridge jumps and reorganization of plate boundaries (f.e. Mathematicians rise and East Pacific rise); 4. During propagation of spreading ridge into the continental crust under influence of hotspot (Aden spreading center and Afar triple junction), under presence of strike-slip faults preceding propagation (possibly, rift zone of California Bay). Ultra-slow spreading is observed now or could have been observed in the past in the following geodynamic environments on transform plate boundaries: 1. In transit zones between two "typical" spreading ridges (f.e. Knipovich ridge); 2. In semi strike-slip/extension zones on the oceanic crust (f.e. American-Antarctic ridge); 3. In the zones of local extension in regional strike-slip areas in pull-apart basins along transform boundaries (Cayman trough, pull-apart basins of the southern border of Scotia plate). Ultra-slow spreading is observed now or could have been observed in the past in the following geodynamic environments on convergent plate boundaries: 1. During back-arc rifting on the stage of transition into back-arc spreading (central

  9. L-H power threshold scaling with magnetic geometry on NSTX and the role of ion orbit loss

    Science.gov (United States)

    Battaglia, D. J.; Chang, C.-S.; Kaye, S. M.; Ku, S.; Maingi, R.; NSTX Team

    2011-10-01

    The L-H power threshold (PLH) on the National Spherical Torus Experiment varies with X-point radius (RX) , plasma current (Ip) , the direction of the ion grad-B drift and the amount of lithium evaporated on the divertor surfaces. The edge Te and Ti (where Te ~ Ti) just prior to the time of the L-H transition vary with the magnetic geometry, but are fairly independent of the neutral fueling rate and lithium conditioning. These observations are consistent with the X-transport theory, which describes the mean edge radial electric field (Er) profile required to prevent non-ambipolar ion loss in a diverted plasma. A guiding-center orbit calculation in the absence of electric fields, collisions and flows provides insight into the dependence of the ion loss, and thus Er, on the magnetic geometry and edge Ti. For example, the number of ion loss orbits remains constant as RX is reduced from 0.64m to 0.47m only if the edge Ti increases by 60%. This is in agreement with self-consistent calculations of Er using the neoclassical XGC0 code and experiments that measured edge Te and Ti to be 40 - 60% larger. Similar agreement is also observed between guiding-center calculations, XGC0 results and the measured PLH versus Ip and ion grad-B direction. Supported by US DOE contracts DE-AC02-09CH11466 and DE-AC05-00OR22725.

  10. Intuitionistic hybrid logic

    DEFF Research Database (Denmark)

    Braüner, Torben

    2011-01-01

    Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area.......Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area....

  11. Continuity Controlled Hybrid Automata

    OpenAIRE

    Bergstra, J. A.; Middelburg, C.A.

    2004-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of hybrid automata as timed transition systems. We also relate the synchronized product operator on hybrid automata to the parallel composition operator of the process algebra. It turns out that the f...

  12. Broadband sidebands generated by parametric instability in lower hybrid current drive experiments on EAST

    Energy Technology Data Exchange (ETDEWEB)

    Amicucci, L., E-mail: luca.amicucci@enea.it; Castaldo, C.; Cesario, R.; Giovannozzi, E.; Tuccillo, A. A. [EUROfusion-ENEA, Centro Ricerche Frascati, Unità Fusione, Frascati (Italy); Ding, B. J.; Li, M. H. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-12-10

    Modern research on nuclear fusion energy, based on the tokamak concept, has strong need of tools for actively driving non-inductive current especially at the periphery of plasma column, where tools available so far have poor efficiency. This is essential for solving one of the most critical problems for thermonuclear reactor, consisting in how to achieve the figure of fusion gain in the context of sufficient stability. The lower hybrid current drive (LHCD) effect has the potential capability of driving current at large radii of reactor plasma with high efficiency [1]. Experiments recently carried out on EAST showed that a strong activity of LH sideband waves (from the RF probe spectra), accompanied by weak core penetration of the coupled LH power, is present when operating at relatively high plasma densities. Previous theoretical results, confirmed by experiments on FTU, showed that the LH sideband phenomenon is produced by parametric instability (PI), which are mitigated by higher plasma edge temperatures. This condition is thus useful for enabling the LH power propagation when operating with profiles having high plasma densities even at the edge. In the present work, we show new PI modeling of EAST plasmas data, obtained in condition of higher plasma edge temperature due to chamber lithisation. The obtained trend of the PI frequencies and growth rates is consistent with data of RF probe spectra, available in different regimes of lithisated and not lithisated vessel. Moreover, these spectra are interpreted as PI effect occurring at the periphery of plasma column, however in the low field side where the LH power is coupled.

  13. Broadband sidebands generated by parametric instability in lower hybrid current drive experiments on EAST

    Science.gov (United States)

    Amicucci, L.; Ding, B. J.; Castaldo, C.; Cesario, R.; Giovannozzi, E.; Li, M. H.; Tuccillo, A. A.

    2015-12-01

    Modern research on nuclear fusion energy, based on the tokamak concept, has strong need of tools for actively driving non-inductive current especially at the periphery of plasma column, where tools available so far have poor efficiency. This is essential for solving one of the most critical problems for thermonuclear reactor, consisting in how to achieve the figure of fusion gain in the context of sufficient stability. The lower hybrid current drive (LHCD) effect has the potential capability of driving current at large radii of reactor plasma with high efficiency [1]. Experiments recently carried out on EAST showed that a strong activity of LH sideband waves (from the RF probe spectra), accompanied by weak core penetration of the coupled LH power, is present when operating at relatively high plasma densities. Previous theoretical results, confirmed by experiments on FTU, showed that the LH sideband phenomenon is produced by parametric instability (PI), which are mitigated by higher plasma edge temperatures. This condition is thus useful for enabling the LH power propagation when operating with profiles having high plasma densities even at the edge. In the present work, we show new PI modeling of EAST plasmas data, obtained in condition of higher plasma edge temperature due to chamber lithisation. The obtained trend of the PI frequencies and growth rates is consistent with data of RF probe spectra, available in different regimes of lithisated and not lithisated vessel. Moreover, these spectra are interpreted as PI effect occurring at the periphery of plasma column, however in the low field side where the LH power is coupled.

  14. The comparison of reticulocyte parameters on the XN-1000 and LH780 hematology analyzer%LH780与XN-1000血液分析仪的网织红细胞参数结果比较

    Institute of Scientific and Technical Information of China (English)

    费选文; 张苏伟; 陈书裕

    2015-01-01

    Objective To analyze the comparability and correlation of reticulocyte parameters on the Beckman‐Coulter LH780 (LH780)and Sysmex XN‐1000(XN‐1000)hematology analyzers .Methods 80 blood samples were measured by the two instru‐ments ,the RBC count ,percentage of Ret(Ret% ) ,Ret value(Ret#)and immature reticulocyte fraction(IRF) were analyzed ,and the correlation of Ret% ,Ret# and IRF between two instruments were also analysed .The correlation between percentage of high laser reticulocyte(HLR% ) of LH780 and percentage of middle fluorescent reticulogyte(MFR% )+percentage of high fluorescent reticu‐locyte(HFR% ) of XN‐1000 were compared using two calculation methods of each instrument ,and the application value of HLR%were analysed .Results No significant differences were founded in RBC count ,Ret% ,and Ret# between the two instruments(P>0 .05) ,while there was statistical difference in IRF between the the two instruments (P<0 .05) .The relative deviation coincidence rate of RBC count was 97 .5% ,the correlation coefficent (r) of Ret% ,Ret# and IRF were 0 .912 ,0 .895 and 0 .666 respectively . There were statistical differences and correlations between HLR% and MFR% + HFR% when using calculation method of XN‐1000 and LH780 respectively(r were 0 .666 and 0 .767 respectively ,P<0 .05) .Conclusion The RBC count could meet the matc‐hing requirement ,and the Ret% and Ret # may be highly correlated on the two instruments .While the reference range of IRF should be established in each instrument .%目的:分析Beckman‐Coulter LH780与Sysmex XN‐1000两台血液分析仪的网织红细胞(Ret)等参数的可比性和相关性。方法用上述两台仪器分别检测80份血常规标本,比较红细胞(RBC )计数、Ret百分率(Ret%)、Ret绝对值(Ret#)和未成熟网织红细胞指数(IRF),并对Ret%、Ret#和IRF进行相关性分析。将LH780的高散射光网织红细胞百分比(HLR%)和XN‐1000

  15. Effects of Central Injection of Anti-LPS Antibody and Blockade of TLR4 on GnRH/LH Secretion during Immunological Stress in Anestrous Ewes

    Directory of Open Access Journals (Sweden)

    Karolina Haziak

    2014-01-01

    Full Text Available The present study was designed to examine the effect of intracerebroventricular (icv administration of antilipopolysaccharide (LPS antibody and blockade of Toll-like receptor 4 (TLR4 during immune stress induced by intravenous (iv LPS injection on the gonadotropin-releasing hormone/luteinizing hormone (GnRH/LH secretion in anestrous ewes. Injection of anti-LPS antibody and TLR4 blockade significantly (P < 0.01 reduced the LPS dependent lowering amount of GnRH mRNA in the median eminence (ME. Moreover, blockade of TLR4 caused restoration of LH-β transcription in the anterior pituitary decreased by the immune stress. However, there was no effect of this treatment on reduced LH release. The results of our study showed that the blockade of TLR4 receptor in the hypothalamus is not sufficient to unblock the release of LH suppressed by the immune/inflammatory challenges. This suggests that during inflammation the LH secretion could be inhibited directly at the pituitary level by peripheral factors such as proinflammatory cytokines and circulating endotoxin as well.

  16. Infertility and ovarian follicle reserve depletion are associated with dysregulation of the FSH and LH receptor density in human antral follicles.

    Science.gov (United States)

    Regan, Sheena L P; Knight, Phil G; Yovich, John L; Stanger, James D; Leung, Yee; Arfuso, Frank; Dharmarajan, Arun; Almahbobi, Ghanim

    2017-02-07

    The low take-home baby rate in older women in Australia (5.8%) undergoing IVF (5.8%) is linked to the depletion of the ovarian reserve of primordial follicles. Oocyte depletion causes an irreversible change to ovarian function. We found that the young patient FSH receptor and LH receptor expression profile on the granulosa cells collected from different size follicles were similar to the expression profile reported in natural cycles in women and sheep. This was reversed in the older patients with poor ovarian reserve. The strong correlation of BMPR1B and FSH receptor density in the young was not present in the older women; whereas, the LH receptor and BMPR1B correlation was weak in the young but was strongly correlated in the older women. The reduced fertilisation and pregnancy rate was associated with a lower LH receptor density and a lack of essential down-regulation of the FSH and LH receptor. The mechanism regulating FSH and LH receptor expression appears to function independently, in vivo, from the dose of FSH gonadotrophin, rather than in response to it. Restoring an optimum receptor density may improve oocyte quality and the pregnancy rate in older women.

  17. High efficiency light harvesting by carotenoids in the LH2 complex from photosynthetic bacteria: unique adaptation to growth under low-light conditions.

    Science.gov (United States)

    Magdaong, Nikki M; LaFountain, Amy M; Greco, Jordan A; Gardiner, Alastair T; Carey, Anne-Marie; Cogdell, Richard J; Gibson, George N; Birge, Robert R; Frank, Harry A

    2014-09-25

    Rhodopin, rhodopinal, and their glucoside derivatives are carotenoids that accumulate in different amounts in the photosynthetic bacterium, Rhodoblastus (Rbl.) acidophilus strain 7050, depending on the intensity of the light under which the organism is grown. The different growth conditions also have a profound effect on the spectra of the bacteriochlorophyll (BChl) pigments that assemble in the major LH2 light-harvesting pigment-protein complex. Under high-light conditions the well-characterized B800-850 LH2 complex is formed and accumulates rhodopin and rhodopin glucoside as the primary carotenoids. Under low-light conditions, a variant LH2, denoted B800-820, is formed, and rhodopinal and rhodopinal glucoside are the most abundant carotenoids. The present investigation compares and contrasts the spectral properties and dynamics of the excited states of rhodopin and rhodopinal in solution. In addition, the systematic differences in pigment composition and structure of the chromophores in the LH2 complexes provide an opportunity to explore the effect of these factors on the rate and efficiency of carotenoid-to-BChl energy transfer. It is found that the enzymatic conversion of rhodopin to rhodopinal by Rbl. acidophilus 7050 grown under low-light conditions results in nearly 100% carotenoid-to-BChl energy transfer efficiency in the LH2 complex. This comparative analysis provides insight into how photosynthetic systems are able to adapt and survive under challenging environmental conditions.

  18. Direct detection of lower hybrid wave using a reflectometer on Alcator C-Moda)

    Science.gov (United States)

    Shiraiwa, S.; Baek, S.; Dominguez, A.; Marmar, E.; Parker, R.; Kramer, G. J.

    2010-10-01

    The possibility of directly detecting a density perturbation produced by lower hybrid (LH) waves using a reflectometer is presented. We investigate the microwave scattering of reflectometer probe beams by a model density fluctuation produced by short wavelength LH waves in an Alcator C-Mod experimental condition. In the O-mode case, the maximum response of phase measurement is found to occur when the density perturbation is approximately centimeters in front of the antenna, where Bragg scattering condition is satisfied. In the X-mode case, the phase measurement is predicted to be more sensitive to the density fluctuation close to the cut-off layer. A feasibility test was carried out using a 50 GHz O-mode reflectometer on the Alcator C-Mod tokamak, and positive results including the detection of 4.6 GHz pump wave and parametric decay instabilities were obtained.

  19. Where does slow axonal transport go?

    Science.gov (United States)

    Terada, Sumio

    2003-12-01

    Axonal transport is the specialized and well-developed intracellular transport system for regulated and/or long-distance transport based on generalized cellular machineries. Among them, slow axonal transport conveys cytoplasmic proteins. The motor molecule, the nature of transporting complex and the transport regulation mechanism for slow transport are still unclarified. There has been a dispute regarding the nature of transporting complex of cytoskeletal proteins, polymer-sliding hypothesis versus subunit-transport theory. Recent data supporting the hypothesis of polymer sliding in cultured neurons only reconfirm the previously reported structure and this inference suffers from the lack of ultrastructural evidence and the direct relevance to the physiological slow transport phenomenon in vivo. Observation of the moving cytoskeletal proteins in vivo using transgenic mice or squid giant axons revealed that subunits do move in a microtubule-dependent manner, strongly indicating the involvement of microtubule-based motor kinesin. If the slow transport rate reflects the intermittent fast transport dependent on kinesin motor, we have to investigate the molecular constituents of the transporting complex in more detail and evaluate why the motor and cargo interaction is so unstable. This kind of weak and fluctuating interaction between various molecular pairs could not be detected by conventional techniques, thus necessitating the establishment of a new experimental system before approaching the molecular regulation problem.

  20. Proton energy dependence of slow neutron intensity

    Energy Technology Data Exchange (ETDEWEB)

    Teshigawara, Makoto; Harada, Masahide; Watanabe, Noboru; Kai, Tetsuya; Sakata, Hideaki; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ooi, Motoki [Hokkaido Univ., Sapporo (Japan)

    2001-03-01

    The choice of the proton energy is an important issue for the design of an intense-pulsed-spallation source. The optimal proton beam energy is rather unique from a viewpoint of the leakage neutron intensity but no yet clear from the slow-neutron intensity view point. It also depends on an accelerator type. Since it is also important to know the proton energy dependence of slow-neutrons from the moderators in a realistic target-moderator-reflector assembly (TMRA). We studied on the TMRA proposed for Japan Spallation Neutron Source. The slow-neutron intensities from the moderators per unit proton beam power (MW) exhibit the maximum at about 1-2 GeV. At higher proton energies the intensity per MW goes down; at 3 and 50 GeV about 0.91 and 0.47 times as low as that at 1 GeV. The proton energy dependence of slow-neutron intensities was found to be almost the same as that of total neutron yield (leakage neutrons) from the same bare target. It was also found that proton energy dependence was almost the same for the coupled and decoupled moderators, regardless the different moderator type, geometry and coupling scheme. (author)

  1. Moving Crystal Slow-Neutron Wavelength Analyser

    DEFF Research Database (Denmark)

    Buras, B.; Kjems, Jørgen

    1973-01-01

    Experimental proof that a moving single crystal can serve as a slow-neutron wavelength analyser of special features is presented. When the crystal moves with a velocity h/(2 md) (h-Planck constant, m-neutron mass, d-interplanar spacing) perpendicular to the diffracting plane and the analysed...

  2. Moving Crystal Slow-Neutron Wavelength Analyser

    DEFF Research Database (Denmark)

    Buras, B.; Kjems, Jørgen

    1973-01-01

    Experimental proof that a moving single crystal can serve as a slow-neutron wavelength analyser of special features is presented. When the crystal moves with a velocity h/(2 md) (h-Planck constant, m-neutron mass, d-interplanar spacing) perpendicular to the diffracting plane and the analysed...

  3. Slowed ageing, welfare, and population problems.

    Science.gov (United States)

    Wareham, Christopher

    2015-10-01

    Biological studies have demonstrated that it is possible to slow the ageing process and extend lifespan in a wide variety of organisms, perhaps including humans. Making use of the findings of these studies, this article examines two problems concerning the effect of life extension on population size and welfare. The first--the problem of overpopulation--is that as a result of life extension too many people will co-exist at the same time, resulting in decreases in average welfare. The second--the problem of underpopulation--is that life extension will result in too few people existing across time, resulting in decreases in total welfare. I argue that overpopulation is highly unlikely to result from technologies that slow ageing. Moreover, I claim that the problem of underpopulation relies on claims about life extension that are false in the case of life extension by slowed ageing. The upshot of these arguments is that the population problems discussed provide scant reason to oppose life extension by slowed ageing.

  4. Exponential estimates of symplectic slow manifolds

    DEFF Research Database (Denmark)

    Kristiansen, Kristian Uldall; Wulff, C.

    2016-01-01

    is motivated by a paper of MacKay from 2004. The method does not notice resonances, and therefore we do not pose any restrictions on the motion normal to the slow manifold other than it being fast and analytic. We also present a stability result and obtain a generalization of a result of Gelfreich and Lerman...

  5. The slow death of most galaxies

    CERN Document Server

    Cattaneo, Andrea

    2016-01-01

    For most galaxies, the shutdown of star formation was a slow process that took four billion years. An analysis of thousands of galaxies suggests that 'strangulation' by their environment was the most likely cause. See Letter on page 192 of Peng, Maiolino and Cochrane (2015), Nature, vol. 521.

  6. Slow light on a printed circuit board.

    Science.gov (United States)

    Lanin, Aleksandr A; Voronin, Aleksandr A; Sokolov, Viktor I; Fedotov, Ilya V; Fedotov, Andrei B; Akhmanov, Aleksandr S; Panchenko, Vladislav Ya; Zheltikov, Aleksei M

    2011-05-15

    Slow-light effects induced by stimulated Raman scattering in polymer waveguides on a printed circuit board are shown to enable a widely tunable delay of broadband optical signals, suggesting an advantageous platform for optical information processing and ultrafast optical waveform transformation. © 2011 Optical Society of America

  7. Origin of pseudotachylites during slow creep experiments

    NARCIS (Netherlands)

    Peč, M.; Stünitz, H.; Heilbronner, R.; Drury, M.; De Capitani, C.

    2012-01-01

    We conducted a series of experiments on granitoid cataclasites under mid-crustal conditions (Pc∼500 MPa, T=300 °C) and slow displacement rates (10−8 ms−1

  8. Exploring the Hedonic Quality of Slow Technology

    OpenAIRE

    Orehovački, Tihomir; Al Sokkar, Abdullah A.M.; Derboven, Jan; Khan, Azam

    2013-01-01

    Pace is an inseparable part of all technologies and consequently represents an interaction design element. Various technology aspects can support hedonic qualities brought about from reflection transformed into unlimited unique experiences, mental rest, and inner peace. This paper argues different approaches to technology pace evaluation. Attributes that contribute to the hedonic quality of slow technology are presented and discussed.

  9. MEAT QUALITY OF LOCAL AND HYBRID RABBITS

    Directory of Open Access Journals (Sweden)

    G. Paci

    2012-08-01

    Full Text Available pH, colour and oxidative status were evaluated to study the effect of rabbit genotype on meat quality. Commercial Hybrids, selected for high growth rate and a local population, characterized by slow growing, were used. Meat quality characteristics of L. lumborum and B. femoris muscles showed significant differences between genotypes. Local population had higher pHu values but lower pH fall values than Hybrids. Hybrids showed higher lightness values and TBARS contents than local population. Meat quality parameters were influenced by genotype. The differences between genotypes could be related to the different degree of maturity because the rabbits, in relation to the different growth rate, were slaughtered at the same weight but at different age.

  10. Uncertainty Quantification in Hybrid Dynamical Systems

    CERN Document Server

    Sahai, Tuhin

    2011-01-01

    Uncertainty quantification (UQ) techniques are frequently used to ascertain output variability in systems with parametric uncertainty. Traditional algorithms for UQ are either system-agnostic and slow (such as Monte Carlo) or fast with stringent assumptions on smoothness (such as polynomial chaos and Quasi-Monte Carlo). In this work, we develop a fast UQ approach for hybrid dynamical systems by extending the polynomial chaos methodology to these systems. To capture discontinuities, we use a wavelet-based Wiener-Haar expansion. We develop a boundary layer approach to propagate uncertainty through separable reset conditions. We also introduce a transport theory based approach for propagating uncertainty through hybrid dynamical systems. Here the expansion yields a set of hyperbolic equations that are solved by integrating along characteristics. The solution of the partial differential equation along the characteristics allows one to quantify uncertainty in hybrid or switching dynamical systems. The above method...

  11. Uncertainty quantification in hybrid dynamical systems

    Science.gov (United States)

    Sahai, Tuhin; Pasini, José Miguel

    2013-03-01

    Uncertainty quantification (UQ) techniques are frequently used to ascertain output variability in systems with parametric uncertainty. Traditional algorithms for UQ are either system-agnostic and slow (such as Monte Carlo) or fast with stringent assumptions on smoothness (such as polynomial chaos and Quasi-Monte Carlo). In this work, we develop a fast UQ approach for hybrid dynamical systems by extending the polynomial chaos methodology to these systems. To capture discontinuities, we use a wavelet-based Wiener-Haar expansion. We develop a boundary layer approach to propagate uncertainty through separable reset conditions. We also introduce a transport theory based approach for propagating uncertainty through hybrid dynamical systems. Here the expansion yields a set of hyperbolic equations that are solved by integrating along characteristics. The solution of the partial differential equation along the characteristics allows one to quantify uncertainty in hybrid or switching dynamical systems. The above methods are demonstrated on example problems.

  12. Hybridized tetraquarks

    Directory of Open Access Journals (Sweden)

    A. Esposito

    2016-07-01

    Full Text Available We propose a new interpretation of the neutral and charged X,Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules but rather a manifestation of the interplay between the two. While meson molecules need a negative or zero binding energy, its counterpart for h-tetraquarks is required to be positive. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs0π± channel by the D0 Collaboration and the negative result presented subsequently by the LHCb Collaboration are understood in this scheme, together with a considerable portion of available data on X,Z particles. Considerations on a state with the same quantum numbers as the X(5568 are also made.

  13. Hybridized Tetraquarks

    CERN Document Server

    Esposito, A.; Polosa, A.D.

    2016-01-01

    We propose a new interpretation of the neutral and charged X, Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules. The latter would require a negative or zero binding energy whose counterpart in h-tetraquarks is a positive quantity. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs pi+- channel by the D0 collaboration and the negative result presented subsequently by the LHCb collaboration are understood in this scheme, together with a considerable portion of available data on X, Z particles. Considerations on a state with the same quantum numbers as the X(5568) are also made.

  14. Fractal THz slow light metamaterial devices

    Science.gov (United States)

    Ito, Shoichi

    Scope and Method of Study: The goal of this study is to investigate the time delay of the fractal H metamaterials in the terahertz regime. This metamaterial contains resonators with two different sizes of H structures which mimic Electromagnetically Induced Transparency and create a transmission window and the corresponding phase dispersion, thus producing slow light. The Al structures were fabricated on silicon wafer and Mylar by using microelectronic lithography and thermal evaporation technique. By using terahertz time-domain spectroscopy, the phase change caused by the slow light system and the actual time delay were obtained. Numerical simulations were carried out to systematize the effect of permittivity and structure dimensions on the optical properties. Findings and Conclusions: We experimentally demonstrated the numerical time delay of the fractal H metamaterial as a slow light device. When permittivity of the substrates increases, the peak position of the transmission window shifts to lower frequency and the bandwidth becomes broader. As a result, silicon performed larger time delay than that of Mylar. By changing the length of the resonator, the bandwidth and the peak position of the transmission window is controllable. At the edges of the transmission window, the negative time delays (fast light) were also observed. Mylar acts as a quaci-free standing structure and allows higher spectral measurement. Moreover, metamaterials fabricated on multiple Mylar films can potentially act as a more effective slow light device. As applications, slow light metamaterials are expected to be used for high-capacity terahertz communication networks, all-optical information processing and sensing devices.

  15. Development of hybrid gas detectors for monitoring neutrons induced from the large intensity proton linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Shim, G. S.; Lee, G. S.; Ahn, S. H. [Korea Univ., Seoul (Korea, Republic of)

    2005-05-15

    Design of a hybrid gaseous detector for slow neutrons. Construction of the hybrid gaseous detector and tests with a {sup 52}Cf isotope and the MC-50 cyclotron. Designs, constructions, and tests for hybrid scintillators using various neutron sensitive materials (2{sup nd} year). Application to development of detectors for high energy physics (2{sup nd} year). Practical R and Ds for applications to medical and industrial purposes (3{sup rd} year)

  16. Properties of slow oscillation during slow-wave sleep and anesthesia in cats

    Science.gov (United States)

    Chauvette, Sylvain; Crochet, Sylvain; Volgushev, Maxim; Timofeev, Igor

    2011-01-01

    Deep anesthesia is commonly used as a model of slow-wave sleep (SWS). Ketamine-xylazine anesthesia reproduces the main features of sleep slow oscillation: slow, large amplitude waves in field potential, which are generated by the alternation of hyperpolarized and depolarized states of cortical neurons. However, direct quantitative comparison of field potential and membrane potential fluctuations during natural sleep and anesthesia is lacking, so it remains unclear how well the properties of sleep slow oscillation are reproduced by the ketamine-xylazine anesthesia model. Here, we used field potential and intracellular recordings in different cortical areas in the cat, to directly compare properties of slow oscillation during natural sleep and ketamine-xylazine anesthesia. During SWS cortical activity showed higher power in the slow/delta (0.1-4 Hz) and spindle (8-14 Hz) frequency range, while under anesthesia the power in the gamma band (30-100 Hz) was higher. During anesthesia, slow waves were more rhythmic and more synchronous across the cortex. Intracellular recordings revealed that silent states were longer and the amplitude of membrane potential around transition between active and silent states was bigger under anesthesia. Slow waves were largely uniform across cortical areas under anesthesia, but in SWS they were most pronounced in associative and visual areas, but smaller and less regular in somatosensory and motor cortices. We conclude that although the main features of the slow oscillation in sleep and anesthesia appear similar, multiple cellular and network features are differently expressed during natural SWS as compared to ketamine-xylazine anesthesia. PMID:22016533

  17. Properties of slow oscillation during slow-wave sleep and anesthesia in cats.

    Science.gov (United States)

    Chauvette, Sylvain; Crochet, Sylvain; Volgushev, Maxim; Timofeev, Igor

    2011-10-19

    Deep anesthesia is commonly used as a model of slow-wave sleep (SWS). Ketamine-xylazine anesthesia reproduces the main features of sleep slow oscillation: slow, large-amplitude waves in field potential, which are generated by the alternation of hyperpolarized and depolarized states of cortical neurons. However, direct quantitative comparison of field potential and membrane potential fluctuations during natural sleep and anesthesia is lacking, so it remains unclear how well the properties of sleep slow oscillation are reproduced by the ketamine-xylazine anesthesia model. Here, we used field potential and intracellular recordings in different cortical areas in the cat to directly compare properties of slow oscillation during natural sleep and ketamine-xylazine anesthesia. During SWS cortical activity showed higher power in the slow/delta (0.1-4 Hz) and spindle (8-14 Hz) frequency range, whereas under anesthesia the power in the gamma band (30-100 Hz) was higher. During anesthesia, slow waves were more rhythmic and more synchronous across the cortex. Intracellular recordings revealed that silent states were longer and the amplitude of membrane potential around transition between active and silent states was bigger under anesthesia. Slow waves were mostly uniform across cortical areas under anesthesia, but in SWS, they were most pronounced in associative and visual areas but smaller and less regular in somatosensory and motor cortices. We conclude that, although the main features of the slow oscillation in sleep and anesthesia appear similar, multiple cellular and network features are differently expressed during natural SWS compared with ketamine-xylazine anesthesia.

  18. Escape for the Slow Solar Wind

    Science.gov (United States)

    Kohler, Susanna

    2017-05-01

    Plasma from the Sun known as the slow solar wind has been observed far away from where scientists thought it was produced. Now new simulations may have resolved the puzzle of where the slow solar wind comes from and how it escapes the Sun to travel through our solar system.An Origin PuzzleA full view of a coronal hole (dark portion) from SDO. The edges of the coronal hole mark the boundary between open and closed magnetic field lines. [SDO; adapted from Higginson et al. 2017]The Suns atmosphere, known as the corona, is divided into two types of regions based on the behavior of magnetic field lines. In closed-field regions, the magnetic field is firmly anchored in the photosphere at both ends of field lines, so traveling plasma is confined to coronal loops and must return to the Suns surface. In open-field regions, only one end of each magnetic field line is anchored in the photosphere, so plasma is able to stream from the Suns surface out into the solar system.This second type of region known as a coronal hole is thought to be the origin of fast-moving plasma measured in our solar system and known as the fast solar wind. But we also observe a slow solar wind: plasma that moves at speeds of less than 500 km/s.The slow solar wind presents a conundrum. Its observational properties strongly suggest it originates in the hot, closed corona rather than the cooler, open regions. But if the slow solar wind plasma originates in closed-field regions of the Suns atmosphere, then how does it escape from the Sun?Slow Wind from Closed FieldsA team of scientists led by Aleida Higginson (University of Michigan) has now used high-resolution, three-dimensional magnetohydrodynamic simulations to show how the slow solar wind can be generated from plasma that starts outin closed-field parts of the Sun.A simulated heliospheric arc, composed of open magnetic field lines. [Higginson et al. 2017]Motions on the Suns surface near the boundary between open and closed-field regions the boundary

  19. Circulating breeding and pre-breeding prolactin and LH are not associated with clutch size in the zebra finch (Taeniopygia guttata).

    Science.gov (United States)

    Ryan, Calen P; Dawson, Alistair; Sharp, Peter J; Meddle, Simone L; Williams, Tony D

    2014-06-01

    Clutch size is a fundamental predictor of avian fitness, widely-studied from evolutionary and ecological perspectives, but surprisingly little is known about the physiological mechanisms regulating clutch size variation. The only formal mechanistic hypothesis for avian clutch-size determination predicts an anti-gonadal effect of circulating prolactin (PRL) via the inhibition of luteinizing hormone (LH), and has become widely-accepted despite little experimental support. Here we investigated the relationship between pre-breeding and breeding plasma PRL and LH and clutch-size in captive-breeding female zebra finches (Taeniopygia guttata). Using a repeated-measures design, we followed individual females from pre-breeding, through multiple breeding attempts, and attempted to decrease PRL using the D2-receptor agonist, bromocriptine. Clutch size was independent of variation in pre-breeding PRL or LH, although pre-breeding LH was negatively correlated with the time between pairing and the onset of laying. Clutch size was independent of variation in plasma PRL on all days of egg-laying. Bromocriptine treatment had no effect on plasma PRL, but in this breeding attempt clutch size was also independent of plasma PRL. Finally, we found no evidence for an inverse relationship between plasma PRL and LH levels, as predicted if PRL had inhibitory effects via LH. Thus, our data fail to provide any support for the involvement of circulating PRL in clutch size determination. These findings suggest that alternative models for hormonal control of avian clutch size need to be considered, perhaps involving downstream regulation of plasma PRL at the level of the ovary, or other hormones that have not been considered to date.

  20. Anti-obesity efficacy of LH-21, a cannabinoid CB1 receptor antagonist with poor brain penetration, in diet-induced obese rats

    Science.gov (United States)

    Alonso, Mónica; Serrano, Antonia; Vida, Margarita; Crespillo, Ana; Hernandez-Folgado, Laura; Jagerovic, Nadine; Goya, Pilar; Reyes-Cabello, Carmen; Perez-Valero, Vidal; Decara, Juan; Macías-González, Manuel; Bermúdez-Silva, Francisco Javier; Suárez, Juan; Rodríguez de Fonseca, Fernando; Pavón, Francisco Javier

    2012-01-01

    BACKGROUND AND PURPOSE Peripheral blockade of cannabinoid CB1 receptors has been proposed as a safe and effective therapy against obesity, putatively devoid of the adverse psychiatric side effects of centrally acting CB1 receptor antagonists. In this study we analysed the effects of LH-21, a peripherally acting neutral cannabinoid receptor antagonist with poor brain penetration, in an animal model of diet-induced obesity. EXPERIMENTAL APPROACH To induce obesity, male Wistar rats were fed a high-fat diet (HFD; 60 kcal% fat) whereas controls received a standard diet (SD; 10 kcal% fat). Following 10 weeks of feeding, animals received a daily i.p. injection of vehicle or 3 mg·kg−1 LH-21 for 10 days. Plasma and liver samples were used for biochemical analyses whereas visceral fat-pad samples were analysed for lipid metabolism gene expression using real-time RT-PCR. In addition, the potential of LH-21 to interact with hepatic cytochrome P450 isoforms and cardiac human Ether-à-go-go Related Gene (hERG) channels was evaluated. KEY RESULTS LH-21 reduced feeding and body weight gain in HFD-fed animals compared with the control group fed SD. In adipose tissue, this effect was associated with decreased gene expression of: (i) leptin; (ii) lipogenic enzymes, including SCD-1; (iii) CB1 receptors; and (iv) both PPARα and PPARγ. Although there were no significant differences in plasma parameters between HFD- and SD-fed rats, LH-21 did not seem to induce hepatic, cardiac or renal toxicity. CONCLUSIONS AND IMPLICATIONS These results support the hypothesis that treatment with the peripherally neutral acting CB1 receptor antagonist, LH-21, may promote weight loss through modulation of visceral adipose tissue. PMID:21951309

  1. Reproductive Performance of Rabbit does Artificially Inseminated with Semen Supplemented with GnRH Analogue [des-Gly10, D-Ala6]-LH-RH Ethylamide.

    Science.gov (United States)

    Gogol, P

    2016-09-01

    The aim of the study was to evaluate, the ability of a GnRH synthetic analogue [des-Gly10, D-Ala6]-LH-RH ethylamide to induce ovulation in rabbit does using intravaginal administration. A total of 138 primiparous lactating does were randomly divided into 4 groups that at the time of insemination received following treatments for ovulation induction: 1 μg of buserelin administered intramuscularly (control group); 5 μg of [des-Gly10, D-Ala6]-LH-RH ethylamide added to the semen dose (D5 group); 10 μg of [des-Gly10, D-Ala6]-LH-RH ethylamide added to the semen dose (D10 group); 15 μg of [des-Gly10, D-Ala6]-LH-RH ethylamide added to the semen dose (D15 group). Kindling rates were 68.8% in D10 and 66.7% in D15 groups and were comparable to that obtained in the control group (72.2%). The kindling rate in group D5 (29.4%) was significantly lower than those recorded in the other groups. The number of live born kits was not significantly affected by the ovulation induction treatment. The results of this study show that [des-Gly10, D-Ala6]-LH-RH ethylamide added directly into the semen dose can effectively stimulate ovulation in rabbits. The dose of 10 μg of [des-Gly10, D-Ala6]-LH-RH ethylamide per doe was sufficient to produce results comparable to those obtained by intramuscular administration of buserelin.

  2. Effects of Orexin A on mRNA Expression of Various Neuropeptides in the Hypothalamus and Pituitary,and on Serum LH Levels in Ovariectomized Gilts

    Institute of Scientific and Technical Information of China (English)

    NING Hong-mei; GE Ya-ming; SU Juan; ZHANG Wen-long; YAO Yuan; YANG Gui-hong; LEI Zhi-hai

    2010-01-01

    Orexin has several biological functions,including the regulation of reproductive endocrine signaling,which has received much attention.However,little is known about the mechanism through which orexin regulates the levels of neuroendocrine hormones and peptides.We injected orexin A or physiological saline into the lateral ventricle of 10 ovariectomized(OVX)gilts,and determined the subsequent changes in serum luteinizing hormone(LH)concentration by using radioimmunoassay(RIA).We also examined the expression of GnRH,NPY,and POMC mRNAs in the hypothalamus and that of LH,follicle-stimulating hormone(FSH),POMC,and ghrelin mRNAs in the pituitary by using semi-quantitative reverse transcription polymerase chain reaction.We found the following results:(1)Orexin A transiently promoted LH secretion; serum LH concentration started to increase at 10 min after the orexin injection,peaked at 30 min,and returned to its initial level at1.5 h;(2)orexin A upregulated GnRH mRNA expression and downregulated NPY and POMC mRNAs expression in the hypothalamus;(3)orexin A upregulated LH and FSH mRNAs expression(FSH,P>0.05),but downregulated ghrelin mRNA expression in the pituitary.No significant effects were observed on the pituitary expression of FSH and POMC mRNAs.Our data suggest that orexin A regulates reproductive function by stimulating GnRH and LH release directly and indirectly via its effects on NPY,POMC and ghrelin expression.

  3. Continuity Controlled Hybrid Automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2004-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of

  4. Continuity controlled Hybrid Automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2008-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of

  5. Cost-effectiveness analysis on the use of rFSH + rLH for the treatment of anovulation in hypogonadotropic hypogonadal women

    Directory of Open Access Journals (Sweden)

    Papaleo E

    2014-06-01

    Full Text Available Enrico Papaleo,1 Carlo Alviggi,2 Giorgio Lorenzo Colombo,3,4 Claudio Pisanelli,5,6 Claudio Ripellino,7 Salvatore Longobardi,8 Pier Luigi Canonico91Centro Scienze della Natalità, Gynecological-Obstetrics Department, San Raffaele Hospital, Vita-Salute San Raffaele, Milan, Italy; 2Department of Neuroscience, Reproductive Sciences and Odontostomatology, University “Federico II” of Naples, Naples, Italy; 3Department of Drug Sciences, University of Pavia, Pavia, Italy; 4SAVE Studi Analisi Valutazioni Economiche, Milan, Italy; 5ACO San Filippo Neri, Rome, Italy; 6Società Italiana Di Farmacia Ospedaliera, Milan, Italy; 7CSD Medical Research Srl, Milan, Italy; 8Medical Department, Merck Serono SpA, Rome, Italy; 9Department of Pharmaceutical Sciences, University of Piemonte Orientale, Novara, Italy Background: Hypogonadotropic hypogonadal women are characterized by ovarian functionality deficiency, caused by low concentrations of follicle-stimulating hormone (FSH and luteinizing hormone (LH. To recover reproduction functionality, recommended therapies for ovarian induction involve injections of FSH and LH medications. Objective: Since important differences exist between recombinant and urinary gonadotropin therapies in terms of efficacy and cost, the objective of this study was to develop a cost-effectiveness model to compare recombinant FSH (rFSH + recombinant LH (rLH and highly purified human menopausal gonadotropin (HP-HMG. Methods: A Markov model was developed, considering three cycles of therapy; probability of pregnancy and miscarriage were considered, and the efficacy was evaluated in terms of pregnancy occurrence. The perspective of the model was that of the Italian Health Service, so only direct cost (drugs, specialist visits, patient examinations, and hospitalizations were included. Results: rFSH + rLH is associated with a higher total cost (€3,453.50 and higher efficacy (0.87 compared with HP-HMG (€2,719.70 and 0.50. rFSH + rLH

  6. Regulative Actions of the Chinese Drugs for Tonifying the Kidney on Gene Expression of the Hypothalamic GnRH, Pituitary FSH, LH and Osteoblastic BGP

    Institute of Scientific and Technical Information of China (English)

    蔡德培; 张炜

    2005-01-01

    It is found that the drugs for nourishing yin to reduce pathogenic fire can significantly down-regulate, and the drags for tonifying the kidney to replenish essence can up-regulate mRNA expression of the hypothalamic GnRH, pituitary FSH, LH and osteoblastic BGP, indicating that the Chinese drugs for tonifying the kidney can regulate gene expression of the hypothalamic GnRH, pituitary FSH, LH, and osteoblastic BGP, which is possibly one of the main mechanisms of the Chinese drug for tonifying the kidney, regulating ephebic development process and improving skeletal development in sexual precocity children.

  7. The role and molecular mechanism of D-aspartic acid in the release and synthesis of LH and testosterone in humans and rats

    Directory of Open Access Journals (Sweden)

    Ronsini Salvatore

    2009-10-01

    Full Text Available Abstract Background D-aspartic acid is an amino acid present in neuroendocrine tissues of invertebrates and vertebrates, including rats and humans. Here we investigated the effect of this amino acid on the release of LH and testosterone in the serum of humans and rats. Furthermore, we investigated the role of D-aspartate in the synthesis of LH and testosterone in the pituitary and testes of rats, and the molecular mechanisms by which this amino acid triggers its action. Methods For humans: A group of 23 men were given a daily dose of D-aspartate (DADAVIT® for 12 days, whereas another group of 20 men were given a placebo. For rats: A group of 10 rats drank a solution of either 20 mM D-aspartate or a placebo for 12 days. Then LH and testosterone accumulation was determined in the serum and D-aspartate accumulation in tissues. The effects of D-aspartate on the synthesis of LH and testosterone were gauged on isolated rat pituitary and Leydig cells. Tissues were incubated with D-aspartate, and then the concentration (synthesis of LH and cGMP in the pituitary and of testosterone and cAMP in the Leydig cells was determined. Results In humans and rats, sodium D-aspartate induces an enhancement of LH and testosterone release. In the rat pituitary, sodium D-aspartate increases the release and synthesis of LH through the involvement of cGMP as a second messenger, whereas in rat testis Leydig cells, it increases the synthesis and release of testosterone and cAMP is implicated as second messenger. In the pituitary and in testes D-Asp is synthesized by a D-aspartate racemase which convert L-Asp into D-Asp. The pituitary and testes possesses a high capacity to trapping circulating D-Asp from hexogen or endogen sources. Conclusion D-aspartic acid is a physiological amino acid occurring principally in the pituitary gland and testes and has a role in the regulation of the release and synthesis of LH and testosterone in humans and rats.

  8. Intracellular mechanism of the action of inhibin on the secretion of follicular stimulating hormone and of luteinizing hormone induced by LH-RH in vitro

    Science.gov (United States)

    Lecomte-Yerna, M. J.; Hazee-Hagelstein, M. T.; Charlet-Renard, C.; Franchimont, P.

    1982-01-01

    The FSH secretion-inhibiting action of inhibin in vitro under basal conditions and also in the presence of LH-RH is suppressed by the addition of MIX, a phosphodiesterase inhibitor. In the presence of LH-RH, inhibin reduces significantly the intracellular level of cAMP in isolated pituitary cells. In contrast, the simultaneous addition of MIX and inhibin raises the cAMP level, and this stimulation is comparable to the increase observed when MIX is added alone. These observations suggest that one mode of action of inhibin could be mediated by a reduction in cAMP within the pituitary gonadotropic cell.

  9. Could the Most Luminous Supernova ASASSN-15lh Be Powered by a Newborn Rapidly-Rotating Strange Quark Star?

    CERN Document Server

    Dai, Z G; Wang, J S; Wang, L J; Yu, Y W

    2015-01-01

    Strange quark stars (SQSs), consisting of quark matter with comparable numbers of deconfined up, down and strange quarks, have so far remained a hypothetical class of compact objects. Observationally, it is difficult to distinguish between SQSs and neutron stars (NSs), because both classes of stars have similar structural and cooling features for stellar masses above one solar mass. Here we show that the most luminous supernova discovered recently, ASASSN-15lh, could have been powered by a newborn strongly-magnetized pulsar rotating with a nearly Keplerian period. A quick rotational-energy loss as a result of gravitational-radiation-driven r-mode instability in a hot young rapidly rotating NS, together with the fact that this instability is highly suppressed due to large bulk viscosity in an SQS, leads to the conclusion that such an ultra-energetic supernova may provide a "smoking gun" signature for the birth of an SQS.

  10. The assay of thyrotropin receptor antibodies with human TSH/LH-CG chimeric receptor expressed on chinese hamster ovary cells

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Ka Hee; Kim, Chang Min [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-12-01

    TSH/LH-CG chimera cDNA is transfected to CHO-K1 cell to obtain the chimeric receptor expressed on the cell surface. The optimal conditions for TSAb and TSBAb measurements are determined using chimeric receptors and under these conditions activity of TSAb and TSBAb in the sera of the Graves` patients. The results obtained are compared to those of TSAb assays using FRTL5 cells CHO-TSHR cells which have wild type human TSH receptor. The transfection procedure of chimeric receptor gene to CHO-K1 cells are on going. The optimal conditions for TSAb and TSBAb measurement using chimeric receptor will be determined after success of transfection procedure. If this study is successfully completed, not only the heterogeneity of Graves. IgG but also pathogenesis of Graves` disease will be elucidated. (author). 25 refs.

  11. Numerical and experimental comparisons of the self-pressurization behavior of an LH2 tank in normal gravity

    Science.gov (United States)

    Barsi, S.; Kassemi, M.

    2008-03-01

    In optimizing the design of cryogenic storage facilities for future in-orbit or on-surface applications the boil-off and the self-pressurization rates must be accurately predicted for different g-levels and for a variety of heat loads and distributions. In this paper, a two-phase CFD model is presented that describes the self-pressurization behavior of a flightweight partially full LH2 tank in normal gravity. Existing experimental data at different fill levels are used to assess the predictive capability of the model. The model's predictions indicate favorable agreement with the experimentally measured pressure histories. Small deviations are observed for the median fill level cases where it is suggested that a non-uniform heat load may be the source of this discrepancy.

  12. Role of ghrelin in regulating rabbit ovarian function and the response to LH and IGF-I.

    Science.gov (United States)

    Sirotkin, Alexander V; Rafay, Ján; Kotwica, Ján; Darlak, Krzysztof; Valenzuela, Francisco

    2009-04-01

    The aim of these in vivo and in vitro studies was to examine the role of ghrelin in the control of plasma hormone concentrations, the proliferation, apoptosis and secretory activity of ovarian granulosa cells and the response of these cells to hormonal treatments. Female rabbits were injected with ghrelin (10 microg/animal/day for one week before ovulation induced by 25IU PMSG and 0.25IU LHRH). On the day of ovulation, blood samples were collected and analyzed for concentrations of progesterone (P(4)), testosterone (T), estradiol (E(2)), estrone-sulphate (ES), insulin-like growth factor I (IGF-I) and leptin (L) by RIA. Some control and ghrelin-treated animals were killed in the periovulatory period, their ovaries were weighed and granulosa cells were isolated and cultured for 2d. Cell proliferation (expression of PCNA) and apoptosis (expression of TdT) were evaluated by immunocytochemistry and TUNEL respectively. Secretion of P(4), T, E(2), IGF-I, and prostaglandin F (PGF) by granulosa cells cultured with and without LH or IGF-I (1, 10 or 100 ng/ml medium) was assessed by RIA. The remaining control and treated animals were kept until parturition, while the number, viability and body weight of pups were recorded. Ghrelin treatment increased rabbit plasma T and decreased ES concentrations but did not influence P(4), E(2), IGF-I or L. Granulosa cells from ghrelin-treated animals showed higher expression of PCNA and lower expression of TdT, than those from control animals. They also secreted less P(4), T, E(2), IGF-I and PGF than granulosa cells from untreated animals. Treatment of cultured granulosa cells with ghrelin (1, 10 or 100 ng/ml medium) either increased (at 1 ng/ml) or decreased (at 10 ng/ml) P(4) secretion, increased (at 100 ng/ml) or decreased (at 10 ng/ml) IGF-I secretion, decreased T (at 1 and 10 ng/ml) and OT (at 1 ng/ml) secretion, and increased (at 100 ng/ml) PGF secretion. LH treatment of cells from control animals stimulated P(4) (at 1 and 10 ng

  13. The assay of thyrotropin receptor antibodies with human TSH/LH-CG chimeric receptor expressed on chinese hamster ovary cells

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Ka Hee; Kim, Chang Min [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1996-12-01

    TSH/LH-CG chimera cDNA is transfected to CHO-K1 cell to obtain the chimeric receptor expressed on the cell surface. The optimal conditions for TSAb and TSBAb measurements are determined using chimeric receptors and under these conditions activity of TSAb and TSBAb in the sera of the Graves` patients. The results obtained are compared to those of TSAb assays using FRTL5 cells CHO-TSHR cells which have wild type human TSH receptor. The transfection procedure of chimeric receptor gene to CHO-K1 cells are on going. The optimal conditions for TSAb and TSBAb measurement using chimeric receptor will be determined after success of transfection procedure. If this study is successfully completed, not only the heterogeneity of Graves. IgG but also pathogenesis of Graves` disease will be elucidated. (author). 25 refs.

  14. Microvesicle-mediated release of soluble LH/hCG receptor (LHCGR from transfected cells and placenta explants

    Directory of Open Access Journals (Sweden)

    Randeva Harpal

    2011-05-01

    Full Text Available Abstract Placental hCG and pitutary LH transduce signals in target tissues through a common receptor (LHCGR. We demonstrate that recombinant LHCGR proteins which include the hormone-binding domain are secreted from transfected cells and that natural LHCGR is also secreted from human placental explants. LHCGR recombinant proteins representing varying lengths of the N-terminal extracellular domain were expressed in Chinese Hamster Ovary cells in suspension culture. Secretion was minimal up to 72h but by 96h 24-37% of the LHCGR had been released into the culture medium. The secreted proteins were folded and sensitive to glycosidases suggesting N-linked glycosylation. Secretion was independent of recombinant size and was mediated via structurally defined membrane vesicles (50-150nm. Similarly cultured human early pregnancy placental explants also released LHCGR via microvesicles. These studies provide the first experimental evidence of the possible mechanistic basis of the secretion of LHCGR.

  15. Slow and fast light in semiconductor waveguides

    DEFF Research Database (Denmark)

    Mørk, Jesper; Hansen, Per Lunnemann; Xue, Weiqi

    2010-01-01

    Investigations of slow and fast light effects in semiconductor waveguides entail interesting physics and point to a number of promising applications. In this review we give an overview of recent progress in the field, in particular focusing on the physical mechanisms of electromagnetically induced...... transparency and coherent population oscillations. While electromagnetically induced transparency has been the most important effect in realizing slowdown effects in atomic gasses, progress has been comparatively slow in semiconductors due to inherent problems of fast dephasing times and inhomogeneous...... broadening in quantum dots. The physics of electromagnetically induced transparency in semiconductors is discussed, emphasizing these limitations and recent suggestions for overcoming them. On the other hand, the mechanism of coherent population oscillations relies on wave mixing effects and is well suited...

  16. A tilted transversely isotropic slowness surface approximation

    KAUST Repository

    Stovas, A.

    2012-05-09

    The relation between vertical and horizontal slownesses, better known as the dispersion relation, for transversely isotropic media with a tilted symmetry axis (TTI) requires solving a quartic polynomial equation, which does not admit a practical explicit solution to be used, for example, in downward continuation. Using a combination of the perturbation theory with respect to the anelliptic parameter and Shanks transform to improve the accuracy of the expansion, we develop an explicit formula for the vertical slowness that is highly accurate for all practical purposes. It also reveals some insights into the anisotropy parameter dependency of the dispersion relation including the low impact that the anelliptic parameter has on the vertical placement of reflectors for a small tilt in the symmetry angle. © 2012 European Association of Geoscientists & Engineers.

  17. Slow scrambling in disordered quantum systems

    CERN Document Server

    Swingle, Brian

    2016-01-01

    Recent work has studied the growth of commutators as a probe of chaos and information scrambling in quantum many-body systems. In this work we study the effect of static disorder on the growth of commutators in a variety of contexts. We find generically that disorder slows the onset of scrambling, and, in the case of a many-body localized state, partially halts it. We access the many-body localized state using a standard fixed point Hamiltonian, and we show that operators exhibit slow logarithmic growth under time evolution. We compare the result with the expected growth of commutators in both localized and delocalized non-interacting disordered models. Finally, based on a scaling argument, we state a conjecture about the effect of weak interactions on the growth of commutators in an interacting diffusive metal.

  18. Polymeric membrane studied using slow positron beam

    Energy Technology Data Exchange (ETDEWEB)

    Hung, W.-S.; Lo, C.-H. [R and D Center for Membrane Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Department of Chemical Engineering, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Cheng, M.-L. [Department of Chemistry, University of Missouri-Kansas City, Kansas City, MO 64110 (United States); Department of Chemical Engineering and Materials Science, Yuan Ze University, Chung-Li 32003, Taiwan (China); Chen Hongmin; Liu Guang; Chakka, Lakshmi [Department of Chemistry, University of Missouri-Kansas City, Kansas City, MO 64110 (United States); Nanda, D.; Tung, K.-L.; Huang, S.-H.; Lee, Kueir-Rarn; Lai, J.-Y. [R and D Center for Membrane Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Department of Chemical Engineering, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Sun Yiming [R and D Center for Membrane Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Department of Chemical Engineering and Materials Science, Yuan Ze University, Chung-Li 32003, Taiwan (China); Yu Changcheng [R and D Center for Membrane Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Department of Physics, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Zhang Renwu [Physical Science Department, Southern Utah University, Cedar City, UT 84720 (United States); Jean, Y.C. [R and D Center for Membrane Technology, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Department of Chemical Engineering, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Department of Chemistry, University of Missouri-Kansas City, Kansas City, MO 64110 (United States)], E-mail: jeany@umkc.edu

    2008-10-31

    A radioisotope slow positron beam has been built at the Chung Yuan Christian University in Taiwan for the research and development in membrane science and technology. Doppler broadening energy spectra and positron annihilation lifetime have been measured as a function of positron energy up to 30 keV in a polyamide membrane prepared by the interfacial polymerization between triethylenetetraamine (TETA) and trimesoyl chloride (TMC) on modified porous polyacrylonitrile (PAN) asymmetric membrane. The multilayer structures and free-volume depth profile for this asymmetric membrane system are obtained. Positron annihilation spectroscopy coupled with a slow beam could provide new information about size selectivity of transporting molecules and guidance for molecular designs in polymeric membranes.

  19. Quake clamps down on slow slip

    Science.gov (United States)

    Wallace, Laura M.; Bartlow, Noel; Hamling, Ian; Fry, Bill

    2014-12-01

    Using continuous GPS (cGPS) data from the Hikurangi subduction zone in New Zealand, we show for the first time that stress changes induced by a local earthquake can arrest an ongoing slow slip event (SSE). The cGPS data show that the slip rate in the northern portion of the 2013/2014 Kapiti SSE decreased abruptly following a nearby intraslab earthquake. We suggest that deceleration of the Kapiti SSE in early 2014 occurred due to a tenfold increase in the normal stress relative to shear stress in the SSE source, induced by the nearby Mw 6.3 earthquake, consistent with expectations of rate and state friction. Our observation of an abrupt halting/slowing of the SSE in response to stress changes imposed by a local earthquake has implications for the strength of fault zones hosting SSEs and supports the premise that static stress changes are an important ingredient in triggering (or delaying) fault slip.

  20. Critical slowing down in a dynamic duopoly

    Science.gov (United States)

    Escobido, M. G. O.; Hatano, N.

    2015-01-01

    Anticipating critical transitions is very important in economic systems as it can mean survival or demise of firms under stressful competition. As such identifying indicators that can provide early warning to these transitions are very crucial. In other complex systems, critical slowing down has been shown to anticipate critical transitions. In this paper, we investigate the applicability of the concept in the heterogeneous quantity competition between two firms. We develop a dynamic model where the duopoly can adjust their production in a logistic process. We show that the resulting dynamics is formally equivalent to a competitive Lotka-Volterra system. We investigate the behavior of the dominant eigenvalues and identify conditions that critical slowing down can provide early warning to the critical transitions in the dynamic duopoly.

  1. Experimental GVD engineering in slow light slot photonic crystal waveguides

    Science.gov (United States)

    Serna, Samuel; Colman, Pierre; Zhang, Weiwei; Le Roux, Xavier; Caer, Charles; Vivien, Laurent; Cassan, Eric

    2016-05-01

    The use in silicon photonics of the new optical materials developed in soft matter science (e.g. polymers, liquids) is delicate because their low refractive index weakens the confinement of light and prevents an efficient control of the dispersion properties through the geometry. We experimentally demonstrate that such materials can be incorporated in 700 μm long slot photonic crystal waveguides, and hence can benefit from both slow-light field enhancement effect and slot-induced ultra-small effective areas. Additionally, we show that their dispersion can be engineered from anomalous to normal regions, along with the presence of multiple zero group velocity dispersion (ZGVD) points exhibiting Normalized Delay Bandwidth Product as high as 0.156. The reported results provide experimental evidence for an accurate control of the dispersion properties of fillable periodical slotted structures in silicon photonics, which is of direct interest for on-chip all-optical data treatment using nonlinear optical effects in hybrid-on-silicon technologies.

  2. MIND diet slows cognitive decline with aging

    OpenAIRE

    Morris, Martha Clare; Tangney, Christy C.; Wang, Yamin; Sacks, Frank Martin; Barnes, Lisa L.; Bennett, David William; Aggarwal, Neelum T

    2015-01-01

    INTRODUCTION: The Mediterranean and dash diets have been shown to slow cognitive decline; however, neither diet is specific to the nutrition literature on dementia prevention. METHODS: We devised the Mediterranean-Dietary Approach to Systolic Hypertension (DASH) diet intervention for neurodegenerative delay (MIND) diet score that specifically captures dietary components shown to be neuroprotective and related it to change in cognition over an average 4.7 years among 960 participants ...

  3. Eldor spin echoes and slow motions

    Science.gov (United States)

    Hornak, Joseph P.; Freed, Jack H.

    1983-10-01

    It is shown how an ELDOR technique based upon spin echoes and rapid stepping of the magnetic field may be employed to measure rotational correlation times, τ R for very slow motions. Experiments on PD-Tempone in 85% glycerol/ D 2O at low temperatures led to τ R values of 10 -4 to 10 -5 s obtained with a simple analysis of the data.

  4. [Pathogenesis and treatment of slow transit constipation].

    Science.gov (United States)

    Zhang, Dongxu; Zhu, Anlong

    2016-12-25

    Slow transit constipation (STC) is generally considered as a complex idiopathic disease affected by multiple factors synergistically. Primarily caused by the condition of gut dysmotility, the transit of intestinal contents turned so slow that the moisture absorption increases, defecation frequency decreases, bowel movement is weakened or even disappeared with or without abdominal distension, dry and hard stool. Its etiology and pathogenesis remains unclear.Recently some researches reported the pathogenesis may be associated with the changes of the enteric nervous system (ENS), such as the change or degeneration of intestinal nerve cells, gut glial cell damage and neurotransmitter changes. Besides, intestinal myopathy, ICC reduction, immune factors, endocrine factors, laxative, mental psychological factors, diet and exercise habits may also be associated with the occurrence and aggravation of STC. The current understanding of STC mechanism can not meet the needs of clinical diagnosis and treatment. Conservative treatment is the main treatment of STC nowadays. For those receiving normative medical treatment but with little effect, surgery is necessary. "Jingling procedure" and "antiperistaltic anastomosis" can both get good efficacy. Treatment aiming at causes of disease will be uncovered as the development of the researches on the pathogenesis and treatment of slow transit constipation.

  5. Method for monitoring slow dynamics recovery

    Science.gov (United States)

    Haller, Kristian C. E.; Hedberg, Claes M.

    2012-11-01

    Slow Dynamics is a specific material property, which for example is connected to the degree of damage. It is therefore of importance to be able to attain proper measurements of it. Usually it has been monitored by acoustic resonance methods which have very high sensitivity as such. However, because the acoustic wave is acting both as conditioner and as probe, the measurement is affecting the result which leads to a mixing of the fast nonlinear response to the excitation and the slow dynamics material recovery. In this article a method is introduced which, for the first time, removes the fast dynamics from the process and allows the behavior of the slow dynamics to be monitored by itself. The new method has the ability to measure at the shortest possible recovery times, and at very small conditioning strains. For the lowest strains the sound speed increases with strain, while at higher strains a linear decreasing dependence is observed. This is the first method and test that has been able to monitor the true material state recovery process.

  6. Shape Memory Composite Hybrid Hinge

    Science.gov (United States)

    Fang, Houfei; Im, Eastwood; Lin, John; Scarborough, Stephen

    2012-01-01

    is reduced to below its glass transition temperature. After the deployable structure is launched in space, the SMC tube is reheated and the hinge is unfolded to deploy the structure. Based on test results, the hybrid hinge can achieve higher than 99.999% shape recovery. The hybrid hinge inherits all of the good characteristics of a tape-spring hinge such as simplicity, light weight, high deployment reliability, and high deployment precision. Conversely, it eliminates the deployment impact that has significantly limited the applications of a tape-spring hinge. The deployment dynamics of a hybrid hinge are in a slow and controllable fashion. The SMC tube of a hybrid hinge is a multifunctional component. It serves as a deployment mechanism during the deployment process, and also serves as a structural component after the hinge is fully deployed, which makes a hybrid hinge much stronger and stiffer than a tape-spring hinge. Unlike a mechanically deploying hinge that uses relatively moving components, a hybrid hinge depends on material deformation for its packing and deployment. It naturally eliminates the microdynamic phenomenon.

  7. Nonlinear dynamical triggering of slow slip

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Paul A [Los Alamos National Laboratory; Knuth, Matthew W [WISCONSIN; Kaproth, Bryan M [PENN STATE; Carpenter, Brett [PENN STATE; Guyer, Robert A [Los Alamos National Laboratory; Le Bas, Pierre - Yves [Los Alamos National Laboratory; Daub, Eric G [Los Alamos National Laboratory; Marone, Chris [PENN STATE

    2010-12-10

    Among the most fascinating, recent discoveries in seismology have been the phenomena of triggered slip, including triggered earthquakes and triggered-tremor, as well as triggered slow, silent-slip during which no seismic energy is radiated. Because fault nucleation depths cannot be probed directly, the physical regimes in which these phenomena occur are poorly understood. Thus determining physical properties that control diverse types of triggered fault sliding and what frictional constitutive laws govern triggered faulting variability is challenging. We are characterizing the physical controls of triggered faulting with the goal of developing constitutive relations by conducting laboratory and numerical modeling experiments in sheared granular media at varying load conditions. In order to simulate granular fault zone gouge in the laboratory, glass beads are sheared in a double-direct configuration under constant normal stress, while subject to transient perturbation by acoustic waves. We find that triggered, slow, silent-slip occurs at very small confining loads ({approx}1-3 MPa) that are smaller than those where dynamic earthquake triggering takes place (4-7 MPa), and that triggered slow-slip is associated with bursts of LFE-like acoustic emission. Experimental evidence suggests that the nonlinear dynamical response of the gouge material induced by dynamic waves may be responsible for the triggered slip behavior: the slip-duration, stress-drop and along-strike slip displacement are proportional to the triggering wave amplitude. Further, we observe a shear-modulus decrease corresponding to dynamic-wave triggering relative to the shear modulus of stick-slips. Modulus decrease in response to dynamical wave amplitudes of roughly a microstrain and above is a hallmark of elastic nonlinear behavior. We believe that the dynamical waves increase the material non-affine elastic deformation during shearing, simultaneously leading to instability and slow-slip. The inferred

  8. Current ramp-up with lower hybrid current drive in EAST

    Science.gov (United States)

    Ding, B. J.; Li, M. H.; Fisch, N. J.; Qin, H.; Li, J. G.; Wilson, J. R.; Kong, E. H.; Zhang, L.; Wei, W.; Li, Y. C.; Wang, M.; Xu, H. D.; Gong, X. Z.; Shen, B.; Liu, F. K.; Shan, J. F.

    2012-12-01

    More economical fusion reactors might be enabled through the cyclic operation of lower hybrid current drive. The first stage of cyclic operation would be to ramp up the plasma current with lower hybrid waves alone in low-density plasma. Such a current ramp-up was carried out successfully on the EAST tokamak. The plasma current was ramped up with a time-averaged rate of 18 kA/s with lower hybrid (LH) power. The average conversion efficiency Pel/PLH was about 3%. Over a transient phase, faster ramp-up was obtained. These experiments feature a separate measurement of the L/R time at the time of current ramp up.

  9. Travelling Waves in Hybrid Chemotaxis Models

    KAUST Repository

    Franz, Benjamin

    2013-12-18

    Hybrid models of chemotaxis combine agent-based models of cells with partial differential equation models of extracellular chemical signals. In this paper, travelling wave properties of hybrid models of bacterial chemotaxis are investigated. Bacteria are modelled using an agent-based (individual-based) approach with internal dynamics describing signal transduction. In addition to the chemotactic behaviour of the bacteria, the individual-based model also includes cell proliferation and death. Cells consume the extracellular nutrient field (chemoattractant), which is modelled using a partial differential equation. Mesoscopic and macroscopic equations representing the behaviour of the hybrid model are derived and the existence of travelling wave solutions for these models is established. It is shown that cell proliferation is necessary for the existence of non-transient (stationary) travelling waves in hybrid models. Additionally, a numerical comparison between the wave speeds of the continuum models and the hybrid models shows good agreement in the case of weak chemotaxis and qualitative agreement for the strong chemotaxis case. In the case of slow cell adaptation, we detect oscillating behaviour of the wave, which cannot be explained by mean-field approximations. © 2013 Society for Mathematical Biology.

  10. Imaging slow slip events and their relationship to seismic slow earthquakes in southwest Japan

    Science.gov (United States)

    Liu, Z.; Moore, A. W.; Owen, S. E.

    2016-12-01

    Past geodetic and seismic studies have revealed a diverse spectrum of fault slip behaviors including slow slip events (SSEs), tremor, low frequency earthquakes (LFEs) and very-low frequency earthquakes (VLFEs). Thanks to its dense GPS and seismic network, Japan has been one of the prime places to study slow slip transients and their relationship to seismic slow earthquakes such as tremor, LFEs and VLFEs. Recent studies show there are complex interactions between slow slip transients, large seismic event, downdip LFEs and up-dip VLFEs in southwest Japan [e.g., Liu et al., 2015]. In this study, we extend our Japan GEONET GPS position time series reanalysis from 1996 to 2016/07/02 using JPL GIPSY/OASIS-II based GPS Network Processor and raw data provided by Geospatial Information Authority of Japan and Caltech. Our analysis uses re-estimated JPL precise orbits, GMF troposphere model, and single receiver ambiguity resolution strategy. The resultant decades long position time series show good consistency and reduced scattering over the entire time period. We apply an in-house developed time series analysis framework to systemically identify and correct the offsets caused by earthquakes, instrument and other unknown sources, and estimate and correct common mode error. We employ a time dependent slip inversion approach to image the spatiotemporal variations of transient slip and investigate their relationship to seismic slow earthquakes. Our application to some recent events such as the one in Bungo Channel region in 2014-2015 shows different spatiotemporal slip pattern as compared to previous recurrent SSEs at the same region. The change in slip pattern, along with a shortened interval, indicates a possible change in recurrent behaviors. Within the same transient event, we find slow slip can occur with and without accompanying tremor/LFEs, suggesting different underlying mechanisms of the two. We are in the process of modeling other slip transients and investigating

  11. Velocity, force, power, and Ca2+ sensitivity of fast and slow monkey skeletal muscle fibers

    Science.gov (United States)

    Fitts, R. H.; Bodine, S. C.; Romatowski, J. G.; Widrick, J. J.

    1998-01-01

    In this study, we determined the contractile properties of single chemically skinned fibers prepared from the medial gastrocnemius (MG) and soleus (Sol) muscles of adult male rhesus monkeys and assessed the effects of the spaceflight living facility known as the experiment support primate facility (ESOP). Muscle biopsies were obtained 4 wk before and immediately after an 18-day ESOP sit, and fiber type was determined by immunohistochemical techniques. The MG slow type I fiber was significantly smaller than the MG type II, Sol type I, and Sol type II fibers. The ESOP sit caused a significant reduction in the diameter of type I and type I/II (hybrid) fibers of Sol and MG type II and hybrid fibers but no shift in fiber type distribution. Single-fiber peak force (mN and kN/m2) was similar between fiber types and was not significantly different from values previously reported for other species. The ESOP sit significantly reduced the force (mN) of Sol type I and MG type II fibers. This decline was entirely explained by the atrophy of these fiber types because the force per cross-sectional area (kN/m2) was not altered. Peak power of Sol and MG fast type II fiber was 5 and 8.5 times that of slow type I fiber, respectively. The ESOP sit reduced peak power by 25 and 18% in Sol type I and MG type II fibers, respectively, and, for the former fiber type, shifted the force-pCa relationship to the right, increasing the Ca2+ activation threshold and the free Ca2+ concentration, eliciting half-maximal activation. The ESOP sit had no effect on the maximal shortening velocity (Vo) of any fiber type. Vo of the hybrid fibers was only slightly higher than that of slow type I fibers. This result supports the hypothesis that in hybrid fibers the slow myosin heavy chain would be expected to have a disproportionately greater influence on Vo.

  12. Atrazine-induced elevation or attenuation of the LH surge in the ovariectomized, estrogen-primed female rat: role of adrenal progesterone

    Science.gov (United States)

    Multiple daily exposures to the herbicide atrazine have been reported to suppress the surge of luteinizing hormone (LH) in both cycling female rats and those that are ovariectomized (OVX) and exogenously primed with steroids. Additional studies have also found elevations in both ...

  13. Bidirectional impact of atrazine-induced elevations in progesterone (P4) on the LH surge in the ovariectomized, estradiol (E2)-primed rat

    Science.gov (United States)

    Multiple daily exposures to the herbicide atrazine (ATZ) have been reported to suppress the luteinizing hormone surge (LHS) in female rats. Exposure has also been found to elevate P4 concentrations, and an increase in P4 is known to have a different directional effect on LH depe...

  14. Bidirectional impact of atrazine-induced elvations in progesterone (P4) on the LH Surge in the ovariectomized (OVX), estradiol (E2)-primed rat

    Science.gov (United States)

    Multiple daily exposures to the herbicide atrazine (ATZ) have been reported to suppress the luteinizing hormone surge (LHS) in female rats. Exposure has also been found to elevate P4 concentrations, and an increase in P4 is known to have a different directional effect on LH depen...

  15. Superovulation of cows with PMSG: Variation in plasma concentrations of progesterone, oestradiol, LH, cortisol, prolactin and PMSG and in number of preovulatory follicles

    NARCIS (Netherlands)

    Bevers, M.M.; Dieleman, S.J.

    1987-01-01

    Forty-two heifers, exhibiting normal oestrous cycles, were treated with 2500 I.U. PMSG and 2 ml prostaglandin (PG) at day 10 and 12 of the oestrous cycle, respectively. In ten heifers progesterone, oestradiol, LH, prolactin, cortisol and PMSG levels were estimated until 10 days after the initiation

  16. LENGTH-HETEROGENEITY POLYMERASE CHAIN REACTION (LH-PCR) AS AN INDICATOR OF STREAM SANITARY AND ECOLOGICAL CONDITION: OPTIMAL SAMPLE SIZE AND HOLDING CONDITIONS

    Science.gov (United States)

    The use of coliform plate count data to assess stream sanitary and ecological condition is limited by the need to store samples at 4oC and analyze them within a 24-hour period. We are testing LH-PCR as an alternative tool to assess the bacterial load of streams, offering a cost ...

  17. Recombinant LH supplementation to recombinant FSH during the final days of controlled ovarian stimulation for in vitro fertilization. A multicentre, prospective, randomized, controlled trial

    DEFF Research Database (Denmark)

    Nyboeandersen, A.; Humaidan, P.; Fried, G.

    2008-01-01

    BACKGROUND: The purpose of this multicentre, multinational trial was to study whether rLH supplementation to recombinant FSH (rFSH) during the late follicular phase increased pregnancy rates. METHODS: After down-regulation with nafarelin, 526 women were randomized on Day 1 of stimulation to use...

  18. First evidence of the role of zonal flows for the L-H transition at marginal input power in the EAST tokamak

    DEFF Research Database (Denmark)

    Xu, G. S.; Wan, B. N.; Wang, H. Q.

    2011-01-01

    A quasiperiodic Er oscillation at a frequency of <4 kHz, much lower than the geodesic-acoustic-mode frequency, with a modulation in edge turbulence preceding and following the low-to-high (L-H) confinement mode transition, has been observed for the first time in the EAST tokamak, using two toroid...

  19. In vitro seasonal variations of LH, FSH and prolactin secretion of the male rat are dependent on the maternal pineal gland.

    Science.gov (United States)

    Díaz, E; Vázquez, N; Fernández, C; Jiménez, V; Esquifino, A; Díaz, B

    2012-01-17

    The maternal pineal gland is involved in the seasonal rhythms entrainment. We evaluate the effect of maternal pinealectomy (PIN-X), also melatonin replacement (PIN-X+MEL) during pregnancy on "in vitro" gonadotropins and prolactin seasonal variations. Male offspring from control, PIN-X and PIN-X+MEL mother Wistar rats were studied at 31 and 60 days of age. In vitro LH release from controls was season-dependent during prepubertal and pubertal periods showing reduced values in winter. The mother pineal gland seems to be important in the entrainment of seasonal variations of in vitro pituitary LH release, since altered secretion showing very high values was observed in summer. Melatonin treatment to PIN-X mothers partially restored the LH response. The effect of pinealectomy upon LH secretion disappears at the pubertal phase. A different pattern was observed for FSH release, without seasonal variations at 31 or at 60 days of age in control offspring, but pinealectomy to mothers or melatonin treatment resulted in seasonal variations. Seasonal influence was also observed in the prolactin pituitary release of controls. PIN-X mother offspring showed delayed seasonal variations at 31 and 60 days of age. The effect of maternal melatonin treatment during pregnancy was observed up to 60 days of age.

  20. Marcación con yodo125 y radioinmunoanálisis de hormonas folículo estimulantes (FSH y Luteinizante (LH humanas

    Directory of Open Access Journals (Sweden)

    Elsa Múnevar

    2009-06-01

    Full Text Available En el presente trabajo se describe la optimización del Radioinmunoanálisis de las hormonas Folículo Estimulantes (FSH y Luteinizante (LH humanas, estableciendo inicialmente las condiciones de marcación con 125 I por el método de la Cloramina T.

  1. The structural role of the carotenoid in the bacterial light-harvesting protein 2 (LH2) of Rhodonbacter capsulatus. A Fourier transform Raman spectroscopy and circular dichroism study.

    Science.gov (United States)

    Zurdo, J; Centeno, M A; Odriozola, J A; Fernández-Cabrera, C; Ramírez, J M

    1995-11-01

    In previous work (Zurdo J, Fernández-Cabrera C and Ramírez JM (1993) Biochem J 290: 531-537), it had been shown that selective extraction of the carotenoid from the light-harvesting protein 2 (LH2) of Rhodobacter capsulatus induced the dissociation of 800-nm absorbing bacteriochlorophyll (Bchl), a 10-nm red shift of 854-nm Bchl, and a decrease of the stability of the protein in detergent solution. In the present study, the Fourier transform Raman and near-infrared circular dichroism spectra of native and carotenoid-depleted LH2 membrane preparations were compared. It was found that while the coupled carbonyls of 854-nm Bchl remained specifically H-bonded to the peptides after carotenoid extraction, the optical activity of the near-infrared electronic transition was significantly altered. Given the excitonic origin of such optical activity, our data suggest that carotenoid extraction elicits a rearrengement of the chromophore cluster and of the associated polypeptide subunits. This implies a significant role of the carotenoid in maintaining the native quaternary structure of the protein, which would be consistent with the observed dissociation of 800-nm Bchl and the loss of solubilized LH2 stability that result from carotenoid removal. There is no evidence for a similar role of the carotenoid in the LH1 protein.

  2. Bidirectional impact of atrazine-induced elevations in progesterone (P4) on the LH surge in the ovariectomized, estradiol (E2)-primed rat

    Science.gov (United States)

    Multiple daily exposures to the herbicide atrazine (ATZ) have been reported to suppress the luteinizing hormone surge (LHS) in female rats. Exposure has also been found to elevate P4 concentrations, and an increase in P4 is known to have a different directional effect on LH depe...

  3. Atrazine-induced elevation or attenuation of the LH surge in the ovariectomized, estrogen-primed female rat: role of adrenal progesterone

    Science.gov (United States)

    Multiple daily exposures to the herbicide atrazine have been reported to suppress the surge of luteinizing hormone (LH) in both cycling female rats and those that are ovariectomized (OVX) and exogenously primed with steroids. Additional studies have also found elevations in both ...

  4. Bidirectional impact of atrazine-induced elvations in progesterone (P4) on the LH Surge in the ovariectomized (OVX), estradiol (E2)-primed rat

    Science.gov (United States)

    Multiple daily exposures to the herbicide atrazine (ATZ) have been reported to suppress the luteinizing hormone surge (LHS) in female rats. Exposure has also been found to elevate P4 concentrations, and an increase in P4 is known to have a different directional effect on LH depen...

  5. Superovulation of cows with PMSG: Variation in plasma concentrations of progesterone, oestradiol, LH, cortisol, prolactin and PMSG and in number of preovulatory follicles

    NARCIS (Netherlands)

    Bevers, M.M.; Dieleman, S.J.

    Forty-two heifers, exhibiting normal oestrous cycles, were treated with 2500 I.U. PMSG and 2 ml prostaglandin (PG) at day 10 and 12 of the oestrous cycle, respectively. In ten heifers progesterone, oestradiol, LH, prolactin, cortisol and PMSG levels were estimated until 10 days after the initiation

  6. Slow Wave Sleep and Long Duration Spaceflight

    Science.gov (United States)

    Whitmire, Alexandra; Orr, Martin; Arias, Diana; Rueger, Melanie; Johnston, Smith; Leveton, Lauren

    2012-01-01

    While ground research has clearly shown that preserving adequate quantities of sleep is essential for optimal health and performance, changes in the progression, order and /or duration of specific stages of sleep is also associated with deleterious outcomes. As seen in Figure 1, in healthy individuals, REM and Non-REM sleep alternate cyclically, with stages of Non-REM sleep structured chronologically. In the early parts of the night, for instance, Non-REM stages 3 and 4 (Slow Wave Sleep, or SWS) last longer while REM sleep spans shorter; as night progresses, the length of SWS is reduced as REM sleep lengthens. This process allows for SWS to establish precedence , with increases in SWS seen when recovering from sleep deprivation. SWS is indeed regarded as the most restorative portion of sleep. During SWS, physiological activities such as hormone secretion, muscle recovery, and immune responses are underway, while neurological processes required for long term learning and memory consolidation, also occur. The structure and duration of specific sleep stages may vary independent of total sleep duration, and changes in the structure and duration have been shown to be associated with deleterious outcomes. Individuals with narcolepsy enter sleep through REM as opposed to stage 1 of NREM. Disrupting slow wave sleep for several consecutive nights without reducing total sleep duration or sleep efficiency is associated with decreased pain threshold, increased discomfort, fatigue, and the inflammatory flare response in skin. Depression has been shown to be associated with a reduction of slow wave sleep and increased REM sleep. Given research that shows deleterious outcomes are associated with changes in sleep structure, it is essential to characterize and mitigate not only total sleep duration, but also changes in sleep stages.

  7. Fast-slow and slow-slow form of atrioventricular nodal reentrant tachycardia sustained by the same reentrant circuit: a case report.

    Science.gov (United States)

    Cantù, Francesco; De Filippo, Paolo; Rordorf, Roberto; De Ferrari, Gaetano M; Frattini, Folco; Petracci, Barbara; Russo, Giovanni; Cerrone, Marina; Landolina, Maurizio

    2005-01-01

    It has been suggested that a reentrant circuit confined to the posterior extensions of the atrioventricular node underlies both fast-slow and slow-slow types of atrioventricular nodal reentrant tachycardia (AVNRT). According to this hypothesis the fast-slow reentrant circuit would be formed by two slow pathways, located in the rightward and leftward posterior extension of the atrioventricular node. Thus, the fast pathway would act as a bystander with respect to the reentrant circuit. We describe the case of a 40-year-old woman with several episodes of palpitations unresponsive to antiarrhythmic drugs. The ECG during symptoms showed a narrow QRS tachycardia with a long ventriculo-atrial interval and a negative P wave in the inferior leads. Electrophysiological study showed the inducibility of a slow-slow AVNRT which rapidly shifted to a fast-slow AVNRT without any change in the duration of the tachycardia cycle. Our observation is in agreement with the hypothesis that the fast-slow reentrant circuit consists of two slow pathways with the fast pathway acting as a bystander.

  8. Counting graphene layers with very slow electrons

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Ludĕk; Mikmeková, Eliška; Müllerová, Ilona [Institute of Scientific Instruments AS CR, v.v.i., Královopolská 147, 61264 Brno (Czech Republic); Lejeune, Michaël [Laboratoire de Physique de la Matière Condensée, Faculté des Sciences d' Amiens, Universite de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex 2 (France)

    2015-01-05

    The study aimed at collection of data regarding the transmissivity of freestanding graphene for electrons across their full energy scale down to the lowest energies. Here, we show that the electron transmissivity of graphene drops with the decreasing energy of the electrons and remains below 10% for energies below 30 eV, and that the slow electron transmissivity value is suitable for reliable determination of the number of graphene layers. Moreover, electrons incident below 50 eV release adsorbed hydrocarbon molecules and effectively clean graphene in contrast to faster electrons that decompose these molecules and create carbonaceous contamination.

  9. Improvement of pedestrian flow by slow rhythm

    Science.gov (United States)

    Yanagisawa, Daichi; Tomoeda, Akiyasu; Nishinari, Katsuhiro

    2012-01-01

    We have developed a simple model for pedestrians by dividing walking velocity into two parts, which are step size and pace of walking (number of steps per unit time). Theoretical analysis on pace indicates that rhythm that is slower than normal-walking pace in a low-density regime increases flow if the flow-density diagram is convex downward in a high-density regime. In order to verify this result, we have performed an experiment with real pedestrians and observed the improvement of flow in a congested situation using slow rhythm.

  10. Lead Slowing Down Spectrometer Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Glen A.; Anderson, Kevin K.; Bonebrake, Eric; Casella, Andrew M.; Danon, Yaron; Devlin, M.; Gavron, Victor A.; Haight, R. C.; Imel, G. R.; Kulisek, Jonathan A.; O' Donnell, J. M.; Weltz, Adam

    2012-06-07

    This report documents the progress that has been completed in the first half of FY2012 in the MPACT-funded Lead Slowing Down Spectrometer project. Significant progress has been made on the algorithm development. We have an improve understanding of the experimental responses in LSDS for fuel-related material. The calibration of the ultra-depleted uranium foils was completed, but the results are inconsistent from measurement to measurement. Future work includes developing a conceptual model of an LSDS system to assay plutonium in used fuel, improving agreement between simulations and measurement, design of a thorium fission chamber, and evaluation of additional detector techniques.

  11. Slow slip event at Kilauea Volcano

    Science.gov (United States)

    Poland, Michael P.; Miklius, Asta; Wilson, J. David; Okubo, Paul G.; Montgomery-Brown, Emily; Segall, Paul; Brooks, Benjamin; Foster, James; Wolfe, Cecily; Syracuse, Ellen; Thurbe, Clifford

    2010-01-01

    Early in the morning of 1 February 2010 (UTC; early afternoon 31 January 2010 local time), continuous Global Positioning System (GPS) and tilt instruments detected a slow slip event (SSE) on the south flank of Kilauea volcano, Hawaii. The SSE lasted at least 36 hours and resulted in a maximum of about 3 centimeters of seaward displacement. About 10 hours after the start of the slip, a flurry of small earthquakes began (Figure 1) in an area of the south flank recognized as having been seismically active during past SSEs [Wolfe et al., 2007], suggesting that the February earthquakes were triggered by stress associated with slip [Segall et al., 2006].

  12. Time course and role of LH and FSH in the expansion of the Leydig cell population at the time of puberty in the rhesus monkey (Macaca mulatta)

    Science.gov (United States)

    Verhagen, I.; Ramaswamy, S.; Teerds, K.J.; Keijer, J.; Plant, T. M.

    2014-01-01

    In higher primates development of the adult population of Leydig cells has received little attention. Here, the emergence of 3β-hydroxysteroid dehydrogenase (HSD3B) positive cells in the testis of the rhesus monkey was examined during spontaneous puberty, and correlated with S-phase labeling in the interstitium at this critical stage of development. In addition, the relative role of LH and FSH in initiating the pubertal expansion of Leydig cells was studied by precociously stimulating the juvenile testis in vivo with pulsatile 11-day infusions of recombinant LH and FSH, either alone or in combination. At the time of castration, testes were immersion fixed in Bouin’s, embedded in paraffin and sectioned at 5 μm. Leydig cells/testis were enumerated using HSD3B as a Leydig cell marker. Leydig cell number per testis increased progressively during puberty to reach values in the adult approximately 10 fold greater than in early pubertal animals. The rise in cell number was associated with an increase in nuclear diameter. That the pubertal expansion of Leydig cell number was driven primarily by the increase in LH secretion at this stage of development was suggested by the finding that precocious stimulation of mid juvenile monkeys with LH, either alone or in combination with that of FSH, resulted in a 20 to 30 fold increase in the number of HSD3B positive cells. Interestingly, precocious FSH stimulation, alone, also resulted in appearance of Leydig cells as indicated by the occasional HSD3B positive cell in the interstitium. The nuclear diameter of these Leydig cells, however was less than that of those generated in response to LH. PMID:25269763

  13. Determination of Ovsynch Efficiency for Estrus Synchronization by Plasma LH and P4 Levels in Nili Ravi Buffalo during Peak and Low Breeding Seasons

    Directory of Open Access Journals (Sweden)

    S. Jabeen, M. Anwar1*, S. M. H. Andrabi1, A. Mehmood1, S. Murtaza2 and M. Shahab

    2013-04-01

    Full Text Available Oestrus synchronization may be used to overcome poor oestrus expression and seasonality of breeding in buffalo (Bubalus bubalis. The present work was conducted to compare the efficiency of an oestrus synchronization protocol “ovsynch” in Nili Ravi buffalo during peak (n=8 and low breeding seasons (n=11 by determining luteinizing hormone (LH peak and progesterone (P4 rise in blood plasma using ELISA. Buffaloes were administered gonadotropin releasing hormone (GnRH analogue (50 µg lecirelin; day 0 followed by prostaglandinF2α (PGF2α analogue (150 µg cloprostenol; day 7 and again GnRH analogue at 36 hours after PGF2α. Blood sampling for LH was started 12 h after PGF2α injection and done at 3 h interval up to 108 h. An animal was considered to have responded to ovsynch protocol if it showed LH peak within 48 h after PGF2α injection (and within 3-6 h after second GnRH injection and showed a P4 concentration of >2.0 ng/ml on day 18 after the 1st GnRH injection. 87.5% animals showed positive response to ovsynch protocol in term of oestrus and ovulation synchronization during the peak season as assessed by LH peak and P4 level while only 36.36 % animals responded to synchronization treatment during low breeding season (P<0.05. The LH peak in responsive animals was 11.48±1.98 and 10.38±1.77 ng/ml in peak and low breeding season respectively. It is concluded that ovsynch protocol in buffaloes resulted in a significantly better response during peak breeding season as compared to that in low breeding season.

  14. Circulating LH/hCG receptor (LHCGR may identify pre-treatment IVF patients at risk of OHSS and poor implantation

    Directory of Open Access Journals (Sweden)

    Chambers Anne E

    2011-12-01

    Full Text Available Abstract Background Successful pregnancy via in vitro fertilization (IVF depends on the recovery of an adequate number of healthy oocytes and on blastocyst implantation following uterine transfer. Two hormones, LH and hCG, utilize a common LH/hCG receptor (LHCGR, variations in which have profound implications in human reproduction. Soluble LHCGR (sLHCGR is released from experimental cell lines and placental explants and it can be detected in the follicular fluid and serum. Methods To evaluate the impact of circulating soluble LHCGR (sLHCGR in fertility treatment, we measured sLHCGR and LH-sLHCGR complex in serum from women seeking IVF using specifically developed quantitative enzyme-linked immunosorbent assays (ELISA. Following an IVF cycle of treatment, patients were grouped according to oocyte yield into low (lower than or equal to 7 oocytes, intermediate (8-14 oocytes and high (greater than or equal to 15 oocytes responders and pregnancy outcome noted. Results Pre-treatment sLHCGR identified many women at risk of ovarian hyperstimulation. Low levels of sLHCGR were associated with pregnancy in both high and low responders but sLHCGR did not significantly affect the treatment outcome of intermediate responders. Low responders who failed to become pregnant had high levels of circulating sLHCGR bound to LH (LH-sLHCGR. Conclusions Pre-treatment measurement of sLHCGR could be used to tailor individual fertility treatment programs and improve outcomes by avoiding ovarian hyperstimulation and poor embryo implantation.

  15. Use of length heterogeneity polymerase chain reaction (LH-PCR) as non-invasive approach for dietary analysis of Svalbard reindeer, Rangifer tarandus platyrhynchus.

    Science.gov (United States)

    Joo, Sungbae; Han, Donguk; Lee, Eun Ju; Park, Sangkyu

    2014-01-01

    To efficiently investigate the forage preference of Svalbard reindeer (Rangifer tarandus platyrhynchus), we applied length-heterogeneity polymerase chain reaction (LH-PCR) based on length differences of internal transcribed spacer (ITS) regions of ribosomal RNA (rRNA) to fecal samples from R. tarandus platyrhynchus. A length-heterogeneity (LH) database was constructed using both collected potential food sources of Svalbard reindeer and fecal samples, followed by PCR, cloning and sequencing. In total, eighteen fecal samples were collected between 2011 and 2012 from 2 geographic regions and 15 samples were successfully amplified by PCR. The LH-PCR analysis detected abundant peaks, 18.6 peaks on an average per sample, ranging from 100 to 500 bp in size and showing distinct patterns associated with both regions and years of sample collection. Principal component analysis (PCA) resulted in clustering of 15 fecal samples into 3 groups by the year of collection and region with a statistically significant difference at 99.9% level. The first 2 principal components (PCs) explained 71.1% of the total variation among the samples. Through comparison with LH database and identification by cloning and sequencing, lichens (Stereocaulon sp. and Ochrolechia sp.) and plant species (Salix polaris and Saxifraga oppositifolia) were detected as the food sources that contributed most to the Svalbard reindeer diet. Our results suggest that the use of LH-PCR analysis would be a non-invasive and efficient monitoring tool for characterizing the foraging strategy of Svalbard reindeer. Additionally, combining sequence information would increase its resolving power in identification of foraged diet components.

  16. Functional characteristics of spirilloxanthin and keto-bearing Analogues in light-harvesting LH2 complexes from Rhodobacter sphaeroides with a genetically modified carotenoid synthesis pathway.

    Science.gov (United States)

    Niedzwiedzki, Dariusz M; Dilbeck, Preston L; Tang, Qun; Mothersole, David J; Martin, Elizabeth C; Bocian, David F; Holten, Dewey; Hunter, C Neil

    2015-01-01

    Light-harvesting 2 (LH2) complexes from a genetically modified strain of the purple photosynthetic bacterium Rhodobacter (Rba.) sphaeroides were studied using static and ultrafast optical methods and resonance Raman spectroscopy. Carotenoid synthesis in the Rba. sphaeroides strain was engineered to redirect carotenoid production away from spheroidene into the spirilloxanthin synthesis pathway. The strain assembles LH2 antennas with substantial amounts of spirilloxanthin (total double-bond conjugation length N=13) if grown anaerobically and of keto-bearing long-chain analogs [2-ketoanhydrorhodovibrin (N=13), 2-ketospirilloxanthin (N=14) and 2,2'-diketospirilloxanthin (N=15)] if grown semi-aerobically (with ratios that depend on growth conditions). We present the photophysical, electronic, and vibrational properties of these carotenoids, both isolated in organic media and assembled within LH2 complexes. Measurements of excited-state energy transfer to the array of excitonically coupled bacteriochlorophyll a molecules (B850) show that the mean lifetime of the first singlet excited state (S1) of the long-chain (N≥13) carotenoids does not change appreciably between organic media and the protein environment. In each case, the S1 state appears to lie lower in energy than that of B850. The energy-transfer yield is ~0.4 in LH2 (from the strain grown aerobically or semi-aerobically), which is less than half that achieved for LH2 that contains short-chain (N≤11) analogues. Collectively, the results suggest that the S1 excited state of the long-chain (N≥13) carotenoids participates little if at all in carotenoid-to-BChl a energy transfer, which occurs predominantly via the carotenoid S2 excited state in these antennas.

  17. Estrogen Modulates Specific Life and Death Signals Induced by LH and hCG in Human Primary Granulosa Cells In Vitro.

    Science.gov (United States)

    Casarini, Livio; Riccetti, Laura; De Pascali, Francesco; Gilioli, Lisa; Marino, Marco; Vecchi, Eugenia; Morini, Daria; Nicoli, Alessia; La Sala, Giovanni Battista; Simoni, Manuela

    2017-04-28

    Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) are glycoprotein hormones used for assisted reproduction acting on the same receptor (LHCGR) and mediating different intracellular signaling. We evaluated the pro- and anti-apoptotic effect of 100 pM LH or hCG, in the presence or in the absence of 200 pg/mL 17β-estradiol, in long-term, serum-starved human primary granulosa cells (hGLC) and a transfected granulosa cell line overexpressing LHCGR (hGL5/LHCGR). To this purpose, phospho-extracellular-regulated kinase 1/2 (pERK1/2), protein kinase B (pAKT), cAMP-responsive element binding protein (pCREB) activation and procaspase 3 cleavage were evaluated over three days by Western blotting, along with the expression of target genes by real-time PCR and cell viability by colorimetric assay. We found that LH induced predominant pERK1/2 and pAKT activation STARD1, CCND2 and anti-apoptotic XIAP gene expression, while hCG mediated more potent CREB phosphorylation, expression of CYP19A1 and procaspase 3 cleavage than LH. Cell treatment by LH is accompanied by increased (serum-starved) cell viability, while hCG decreased the number of viable cells. The hCG-specific, pro-apoptotic effect was blocked by a physiological dose of 17β-estradiol, resulting in pAKT activation, lack of procaspase 3 cleavage and increased cell viability. These results confirm that relatively high levels of steroidogenic pathway activation are linked to pro-apoptotic signals in vitro, which may be counteracted by other factors, i.e., estrogens.

  18. Analysis of the role of the LH92_11085 gene of a biofilm hyper-producing Acinetobacter baumannii strain on biofilm formation and attachment to eukaryotic cells.

    Science.gov (United States)

    Álvarez-Fraga, Laura; Pérez, Astrid; Rumbo-Feal, Soraya; Merino, María; Vallejo, Juan Andrés; Ohneck, Emily J; Edelmann, Richard E; Beceiro, Alejandro; Vázquez-Ucha, Juan C; Valle, Jaione; Actis, Luis A; Bou, Germán; Poza, Margarita

    2016-05-18

    Acinetobacter baumannii is a nosocomial pathogen that has a considerable ability to survive in the hospital environment partly due to its capacity to form biofilms. The first step in the process of establishing an infection is adherence of the bacteria to target cells. Chaperone-usher pili assembly systems are involved in pilus biogenesis pathways that play an important role in adhesion to host cells and tissues as well as medically relevant surfaces. After screening a collection of strains, a biofilm hyper-producing A. baumannii strain (MAR002) was selected to describe potential targets involved in pathogenicity. MAR002 showed a remarkable ability to form biofilm and attach to A549 human alveolar epithelial cells. Analysis of MAR002 using transmission electron microscopy (TEM) showed a significant presence of pili on the bacterial surface. Putative protein-coding genes involved in pili formation were identified based on the newly sequenced genome of MAR002 strain (JRHB01000001/2 or NZ_JRHB01000001/2). As assessed by qRT-PCR, the gene LH92_11085, belonging to the operon LH92_11070-11085, is overexpressed (ca. 25-fold more) in biofilm-associated cells compared to exponential planktonic cells. In the present work we investigate the role of this gene on the MAR002 biofilm phenotype. Scanning electron microscopy (SEM) and biofilm assays showed that inactivation of LH92_11085 gene significantly reduced bacterial attachment to A549 cells and biofilm formation on plastic, respectively. TEM analysis of the LH92_11085 mutant showed the absence of long pili formations normally present in the wild-type. These observations indicate the potential role this LH92_11085 gene could play in the pathobiology of A baumannii.

  19. Liquid crystal light valves for slow light and applications

    Energy Technology Data Exchange (ETDEWEB)

    Residori, S; Bortolozzo, U [INLN, CNRS, University de Nice Sophia-Antipolis, 1361 route des Lucioles, 06560 Valbonne (France); Huignard, J P, E-mail: jean-pierre.huignard@thalesgroup.co [Thales Research and Technology, RD 128 91767, Palaiseau Cedex (France)

    2010-02-01

    The large dispersive properties of wave mixing in liquid crystal light-valves allow obtaining fast and slow light with tunable group velocities. A slow light interferometer is shown by using this interaction.

  20. Slow-plasmon resonant nano-strip antennas

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Beermann, Jonas; Boltasseva, Alexandra

    2008-01-01

    Resonant scattering by gold nanostrip antennas due to constructive interference of counterpropagating slow surface plasmon polaritons SPPs is analyzed, including the quasistatic limit of ultrasmall antennas, and experimentally demonstrated. The phase of slow SPP reflection by strip ends is found...

  1. Slow-plasmon resonant-nanostrip antennas: Analysis and demonstration

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Beermann, J.; Boltasseva, Alexandra;

    2008-01-01

    Resonant scattering by gold nanostrip antennas due to constructive interference of counterpropagating slow surface plasmon polaritons (SPPs) is analyzed, including the quasistatic limit of ultrasmall antennas, and experimentally demonstrated. The phase of slow SPP reflection by strip ends is found...

  2. Sustainable Development of Slow Fashion Businesses: Customer Value Approach

    Directory of Open Access Journals (Sweden)

    Sojin Jung

    2016-06-01

    Full Text Available As an alternative to the prevalent fast fashion model, slow fashion has emerged as a way of enhancing sustainability in the fashion industry, yet how slow fashion can enhance profitability is still largely unknown. Based on a customer value creation framework, this study empirically tested a structural model that specified the slow fashion attributes that contribute to creating perceived customer value, which subsequently increases a consumer’s intention to buy and pay a price premium for slow fashion products. An analysis of 221 U.S. consumer data revealed that delivering exclusive product value is significantly critical in creating customer value for slow fashion, and customer value, in turn, positively affects consumers’ purchase intentions. Further analysis also revealed that different slow fashion attributes distinctively affect customer value. This provides potential strategies on which slow fashion businesses can focus to secure an economically sustainable business model, thereby continuously improving environmental and social sustainability with the slow fashion ideal.

  3. Slow-light effects in photonic crystal membrane lasers

    DEFF Research Database (Denmark)

    Xue, Weiqi; Yu, Yi; Ottaviano, Luisa

    2015-01-01

    In this paper, we present a systematic investigation of photonic crystal cavity laser operating in the slow-light regime. The dependence of lasing threshold on the effect of slow-light will be particularly highlighted.......In this paper, we present a systematic investigation of photonic crystal cavity laser operating in the slow-light regime. The dependence of lasing threshold on the effect of slow-light will be particularly highlighted....

  4. Principles of Slow Fashion Application in Clothing Collection Creation

    OpenAIRE

    Agnė Antanavičiūtė; Vaida Dobilaitė

    2015-01-01

    Today we can clearly see the damage which is caused by fast fashion production and mass consumption. Therefore, a relevant issue is how to reduce consumption, waste, and threat to the environment and human health. Research into the slow fashion designers approach towards eco-friendly and slow fashion products shows that it is necessary to spread ideas of slow fashion widely and teach users about ecologically friendly clothing. Therefore, this paper analyses theoretical and practical slow fash...

  5. Nonlinear Gain Saturation in Active Slow Light Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Chen, Yaohui; Mørk, Jesper

    2013-01-01

    We present a quantitative three-dimensional analysis of slow-light enhanced traveling wave amplification in an active semiconductor photonic crystal waveguides. The impact of slow-light propagation on the nonlinear gain saturation of the device is investigated.......We present a quantitative three-dimensional analysis of slow-light enhanced traveling wave amplification in an active semiconductor photonic crystal waveguides. The impact of slow-light propagation on the nonlinear gain saturation of the device is investigated....

  6. Poloidal rotation induced by injecting lower hybrid waves in tokamak plasma edge

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The poloidal rotation of the magnetized edge plasma in tokamak driven by theponderomotive force which is generated by injecting lower hybrid wave(LHW) electric field hasbeen studied. The LHW is launched from a waveguide in the plasma edge, and by Brambilla’sgrill theory, analytic expressions for the wave electric field in the slab model of an inhomogeneouscold plasma have been derived. It is shown that a strong wave electric field will be generated inthe plasma edge by injecting LH wave of the power in MW magnitude, and this electric field willinduce a poloidal rotation with a sheared poloidal velocity.PACS: 52.55.Fa

  7. Spectroscopic evidence for triplet excitation energy transfer among carotenoids in the LH2 complex from photosynthetic bacterium Rhodopseudomonas palustris

    Institute of Scientific and Technical Information of China (English)

    FENG Juan; WANG Qian; ZHANG Xujia; HUANG Youguo; AI Xicheng; ZHANG Xingkang; ZHANG Jianping

    2004-01-01

    The LH2 complex from Rhodopsudomonas (Rps.) palustris is unique in the heterogeneous carotenoid compositions. The dynamics of triplet excited state Carotenoids (3Car*) has been investigated by means of sub-microsecond time-resolved absorption spectroscopy both at physiological temperature (295 K) and at cryogenic temperature (77 K). Broad and asymmetric Tn←T1 transient absorption was observed at room temperature following the photo-excitation of Car at 532 nm, which suggests the contribution from various carotenoid compositions having different numbers of conjugated C=C double bonds (NC=C). The triplet absorption bands of different carotenoids, which superimposed at room temperature, could be clearly distinguished upon decreasing the temperature down to 77 K. At room temperature the shorter-wavelength side of the main Tn←T1 absorption band decayed rapidly to reach a spectral equilibration with a characteristic time constant of~1 μs, the same spectral dynamics, however, was not observed at 77 K. The aforementioned spectral dynamics can be explained in terms of the triplet-excitation transfer among heterogeneous carotenoid compositions. Global spectral analysis was applied to the time-resolved spectra at room temperature, which revealed two spectral components peaked at 545 and 565 nm, and assignable to the Tn←T1 absorption of Cars with NC=C=11 and NC=C=13, respectively. Surprisingly, the decay time constant of a shorter-con- jugated Car, I.e. 0.72 μs (aerobic) and 1.36 μs (anaerobic), is smaller than that of a longer-con- jugated Car, I.e. 2.12 μs (aerobic) and 3.75 μs (anaerobic), which is contradictory to the general rule of carotenoids and relative polyenes. The results are explained in terms of triplet-excitation transfer among different types of Cars. It is postulated that two Cars with different conjugation lengths coexist in an α,β-subunit in the LH2 complex.

  8. The role of the plasma current in turbulence decrease during lower hybrid current drive

    Science.gov (United States)

    Antar, G.; Ekedahl, A.; Goniche, M.; Asghar, A.; Žàček, F.

    2017-03-01

    The interaction of radio frequency (RF) waves with edge turbulence has resurfaced after the results obtained on many tokamaks showing that edge turbulence decreases when the ion cyclotron frequency heating (ICRH) is switched on. Using the lower hybrid (LH) waves to drive current into tokamak plasmas, this issue presented contradicting results with some tokamaks (FTU & HT-7) showing a net decrease, similar to the ICRH results, and others (Tore Supra) did not. In this article, these apparent discrepancies among tokamaks and RF wave frequencies are removed. It is found that turbulence large-scale structures in the scrape-off layer decrease at high enough plasma currents (Ip) on the Tore Supra tokamak. We distinguish three regimes: At low Ip's, no modification is detected with statistical properties of turbulence similar to ohmic plasmas even with PLH reaching 4.8 MW. At moderate plasma currents, turbulence properties are modified only at a high LH power. At high plasma currents, turbulent large scales are reduced to values smaller than 1 cm, and this is accompanied by a net decrease in the level of turbulence of about 30% even with a moderate LH power.

  9. An arc control and protection system for the JET lower hybrid antenna based on an imaging system

    Science.gov (United States)

    Figueiredo, J.; Mailloux, J.; Kirov, K.; Kinna, D.; Stamp, M.; Devaux, S.; Arnoux, G.; Edwards, J. S.; Stephen, A. V.; McCullen, P.; Hogben, C.

    2014-11-01

    Arcs are the potentially most dangerous events related to Lower Hybrid (LH) antenna operation. If left uncontrolled they can produce damage and cause plasma disruption by impurity influx. To address this issue an arc real time control and protection imaging system for the Joint European Torus (JET) LH antenna has been implemented. The LH system is one of the additional heating systems at JET. It comprises 24 microwave generators (klystrons, operating at 3.7 GHz) providing up to 5 MW of heating and current drive to the JET plasma. This is done through an antenna composed of an array of waveguides facing the plasma. The protection system presented here is based primarily on an imaging arc detection and real time control system. It has adapted the ITER like wall hotspot protection system using an identical CCD camera and real time image processing unit. A filter has been installed to avoid saturation and spurious system triggers caused by ionization light. The antenna is divided in 24 Regions Of Interest (ROIs) each one corresponding to one klystron. If an arc precursor is detected in a ROI, power is reduced locally with subsequent potential damage and plasma disruption avoided. The power is subsequently reinstated if, during a defined interval of time, arcing is confirmed not to be present by image analysis. This system was successfully commissioned during the restart phase and beginning of the 2013 scientific campaign. Since its installation and commissioning, arcs and related phenomena have been prevented. In this contribution we briefly describe the camera, image processing, and real time control systems. Most importantly, we demonstrate that an LH antenna arc protection system based on CCD camera imaging systems works. Examples of both controlled and uncontrolled LH arc events and their consequences are shown.

  10. An arc control and protection system for the JET lower hybrid antenna based on an imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, J., E-mail: joao.figueiredo@jet.efda.org [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal and EFDA-CSU, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Mailloux, J.; Kirov, K.; Kinna, D.; Stamp, M.; Devaux, S.; Arnoux, G.; Edwards, J. S.; Stephen, A. V.; McCullen, P.; Hogben, C. [EURATOM/CCFE Fusion Association, Culham Science Center, Abingdon OX14 3DB (United Kingdom)

    2014-11-15

    Arcs are the potentially most dangerous events related to Lower Hybrid (LH) antenna operation. If left uncontrolled they can produce damage and cause plasma disruption by impurity influx. To address this issue an arc real time control and protection imaging system for the Joint European Torus (JET) LH antenna has been implemented. The LH system is one of the additional heating systems at JET. It comprises 24 microwave generators (klystrons, operating at 3.7 GHz) providing up to 5 MW of heating and current drive to the JET plasma. This is done through an antenna composed of an array of waveguides facing the plasma. The protection system presented here is based primarily on an imaging arc detection and real time control system. It has adapted the ITER like wall hotspot protection system using an identical CCD camera and real time image processing unit. A filter has been installed to avoid saturation and spurious system triggers caused by ionization light. The antenna is divided in 24 Regions Of Interest (ROIs) each one corresponding to one klystron. If an arc precursor is detected in a ROI, power is reduced locally with subsequent potential damage and plasma disruption avoided. The power is subsequently reinstated if, during a defined interval of time, arcing is confirmed not to be present by image analysis. This system was successfully commissioned during the restart phase and beginning of the 2013 scientific campaign. Since its installation and commissioning, arcs and related phenomena have been prevented. In this contribution we briefly describe the camera, image processing, and real time control systems. Most importantly, we demonstrate that an LH antenna arc protection system based on CCD camera imaging systems works. Examples of both controlled and uncontrolled LH arc events and their consequences are shown.

  11. An arc control and protection system for the JET lower hybrid antenna based on an imaging system.

    Science.gov (United States)

    Figueiredo, J; Mailloux, J; Kirov, K; Kinna, D; Stamp, M; Devaux, S; Arnoux, G; Edwards, J S; Stephen, A V; McCullen, P; Hogben, C

    2014-11-01

    Arcs are the potentially most dangerous events related to Lower Hybrid (LH) antenna operation. If left uncontrolled they can produce damage and cause plasma disruption by impurity influx. To address this issue an arc real time control and protection imaging system for the Joint European Torus (JET) LH antenna has been implemented. The LH system is one of the additional heating systems at JET. It comprises 24 microwave generators (klystrons, operating at 3.7 GHz) providing up to 5 MW of heating and current drive to the JET plasma. This is done through an antenna composed of an array of waveguides facing the plasma. The protection system presented here is based primarily on an imaging arc detection and real time control system. It has adapted the ITER like wall hotspot protection system using an identical CCD camera and real time image processing unit. A filter has been installed to avoid saturation and spurious system triggers caused by ionization light. The antenna is divided in 24 Regions Of Interest (ROIs) each one corresponding to one klystron. If an arc precursor is detected in a ROI, power is reduced locally with subsequent potential damage and plasma disruption avoided. The power is subsequently reinstated if, during a defined interval of time, arcing is confirmed not to be present by image analysis. This system was successfully commissioned during the restart phase and beginning of the 2013 scientific campaign. Since its installation and commissioning, arcs and related phenomena have been prevented. In this contribution we briefly describe the camera, image processing, and real time control systems. Most importantly, we demonstrate that an LH antenna arc protection system based on CCD camera imaging systems works. Examples of both controlled and uncontrolled LH arc events and their consequences are shown.

  12. Automated classification of spatiotemporal characteristics of gastric slow wave propagation.

    Science.gov (United States)

    Paskaranandavadivel, Niranchan; Gao, Jerry; Du, Peng; O'Grady, Gregory; Cheng, Leo K

    2013-01-01

    Gastric contractions are underpinned by an electrical event called slow wave activity. High-resolution electrical mapping has recently been adapted to study gastric slow waves at a high spatiotemporal detail. As more slow wave data becomes available, it is becoming evident that the spatial organization of slow wave plays a key role in the initiation and maintenance of gastric dsyrhythmias in major gastric motility disorders. All of the existing slow wave signal processing techniques deal with the identification and partitioning of recorded wave events, but not the analysis of the slow wave spatial organization, which is currently performed visually. This manual analysis is time consuming and is prone to observer bias and error. We present an automated approach to classify spatial slow wave propagation patterns via the use of Pearson cross correlations. Slow wave propagations were grouped into classes based on their similarity to each other. The method was applied to high-resolution gastric slow wave recordings from four pigs. There were significant changes in the velocity of the gastric slow wave wavefront and the amplitude of the slow wave event when there was a change in direction to the slow wave wavefront during dsyrhythmias, which could be detected with the automated approach.

  13. The Persistence of a Slow Manifold with Bifurcation

    DEFF Research Database (Denmark)

    Kristiansen, Kristian Uldall; Palmer, P.; Robert, M.

    2012-01-01

    his paper considers the persistence of a slow manifold with bifurcation in a slow-fast two degree of freedom Hamiltonian system. In particular, we consider a system with a supercritical pitchfork bifurcation in the fast space which is unfolded by the slow coordinate. The model system is motivated...

  14. Slow features nonnegative matrix factorization for temporal data decomposition

    NARCIS (Netherlands)

    Zafeiriou, Lazaros; Nikitidis, Symeon; Zafeiriou, Stefanos; Pantic, Maja

    2014-01-01

    In this paper, we combine the principles of temporal slowness and nonnegative parts-based learning into a single framework that aims to learn slow varying parts-based representations of time varying sequences. We demonstrate that the proposed algorithm arises naturally by embedding the Slow Features

  15. Good, Clean, Fair: The Rhetoric of the Slow Food Movement

    Science.gov (United States)

    Schneider, Stephen

    2008-01-01

    This article outlines the origins of the Slow Food movement before examining the ways in which Slow Food rhetoric seeks to redefine gastronomy and combat the more deleterious effects of globalization. In articulating a new gastronomy, Slow Food founder Carlo Petrini attempts to reconstruct the gastronomy of Jean Anthelme Brillat-Savarin, at once…

  16. Slow Photons for Photocatalysis and Photovoltaics.

    Science.gov (United States)

    Liu, Jing; Zhao, Heng; Wu, Min; Van der Schueren, Benoit; Li, Yu; Deparis, Olivier; Ye, Jinhua; Ozin, Geoffrey A; Hasan, Tawfique; Su, Bao-Lian

    2017-02-06

    Solar light is widely recognized as one of the most valuable renewable energy sources for the future. However, the development of solar-energy technologies is severely hindered by poor energy-conversion efficiencies due to low optical-absorption coefficients and low quantum-conversion yield of current-generation materials. Huge efforts have been devoted to investigating new strategies to improve the utilization of solar energy. Different chemical and physical strategies have been used to extend the spectral range or increase the conversion efficiency of materials, leading to very promising results. However, these methods have now begun to reach their limits. What is therefore the next big concept that could efficiently be used to enhance light harvesting? Despite its discovery many years ago, with the potential for becoming a powerful tool for enhanced light harvesting, the slow-photon effect, a manifestation of light-propagation control due to photonic structures, has largely been overlooked. This review presents theoretical as well as experimental progress on this effect, revealing that the photoreactivity of materials can be dramatically enhanced by exploiting slow photons. It is predicted that successful implementation of this strategy may open a very promising avenue for a broad spectrum of light-energy-conversion technologies.

  17. Slow internal protein dynamics in solution

    Science.gov (United States)

    Biehl, R.; Richter, D.

    2014-12-01

    Large-scale domain dynamics in proteins are found when flexible linkers or hinges connect domains. The related conformational changes are often related to the function of the protein, for example by arranging the active center after substrate binding or allowing transport and release of products. The adaptation of a specific active structure is referred to as ‘induced fit’ and is challenged by models such as ‘conformational sampling’. Newer models about protein function include some flexibility within the protein structure or even internal dynamics of the protein. As larger domains contribute to the configurational changes, the timescale of the involved motions is slowed down. The role of slow domain dynamics is being increasingly recognized as essential to understanding the function of proteins. Neutron spin echo spectroscopy (NSE) is a technique that is able to access the related timescales from 0.1 up to several hundred nanoseconds and simultaneously covers the length scale relevant for protein domain movements of several nanometers distance between domains. Here we focus on these large-scale domain fluctuations and show how the structure and dynamics of proteins can be assessed by small-angle neutron scattering and NSE.

  18. Maxwell Equations for Slow-Moving Media

    Science.gov (United States)

    Rozov, Andrey

    2015-12-01

    In the present work, the Minkowski equations obtained on the basis of theory of relativity are used to describe electromagnetic fields in moving media. But important electromagnetic processes run under non-relativistic conditions of slow-moving media. Therefore, one should carry out its description in terms of classical mechanics. Hertz derived electrodynamic equations for moving media within the frame of classical mechanics on the basis of the Maxwell theory. His equations disagree with the experimental data concerned with the moving dielectrics. In the paper, a way of description of electromagnetic fields in slow-moving media on the basis of the Maxwell theory within the frame of classical mechanics is offered by combining the Hertz approach and the experimental data concerned with the movement of dielectrics in electromagnetic fields. Received Maxwell equations lack asymmetry in the description of the reciprocal electrodynamic action of a magnet and a conductor and conform to known experimental data. Comparative analysis of the Minkowski and Maxwell models is carried out.

  19. Colectomy for idiopathic slow transit constipation

    Institute of Scientific and Technical Information of China (English)

    童卫东; 刘宝华; 张胜本; 张连阳; 黄显凯

    2003-01-01

    Objective: To evaluate the intervention of colectomy on a group of patients with idiopathic slow transit constipation (STC).Methods: Thirty-four patients with STC, underwent colectomy during recent 10 years in our department, were subjected and followed for a mean length of 34 months, and their colon transits, defecograms, colonoscopic examination, sex hormone detection, and immunohistochemical studies were retrospectively reviewed.Results: The colonic transit time ranged from 96 to 240 h, with a mean time of 136 h.Eighty-five percent of patients (29/34) accompanied with outlet obstructed constipation, and 50% (17/34) showed abnormal sex hormone levels.Colectomy obtained satisfactory results in most patients, except one case of recurrence.Moreover, more neurons positive to nitric oxide synthase (NOS) and lesser to vasoactive intestinal polypeptide (VIP) were seen in the colonic myenteric plexus.Conclusion: Colectomy produces a satisfactory functional outcome in the majority of patients undergoing surgery for slow transit constipation, but accompanied pelvic dysfunction must be corrected simultaneously.

  20. From hybrid swarms to swarms of hybrids

    Science.gov (United States)

    The introgression of modern humans (Homo sapiens) with Neanderthals 40,000 YBP after a half-million years of separation, may have led to the best example of a hybrid swarm on earth. Modern trade and transportation in support of the human hybrids has continued to introduce additional species, genotyp...

  1. The Hybrid Museum: Hybrid Economies of Meaning

    DEFF Research Database (Denmark)

    Vestergaard, Vitus

    2013-01-01

    this article shows that there are two different museum mindsets where the second mindset leans towards participatory practices. It is shown how a museum can support a hybrid economy of meaning that builds on both a user generated economy of meaning and an institutional economy of meaning and adds value to both....... Such a museum is referred to as a hybrid museum....

  2. Hydraulic Hybrid Vehicles

    Science.gov (United States)

    EPA and the United Parcel Service (UPS) have developed a hydraulic hybrid delivery vehicle to explore and demonstrate the environmental benefits of the hydraulic hybrid for urban pick-up and delivery fleets.

  3. Hybrid Management in Hospitals

    DEFF Research Database (Denmark)

    Byrkjeflot, Haldor; Jespersen, Peter Kragh

    2010-01-01

    Artiklen indeholder et litteraturbaseret studium af ledelsesformer i sygehuse, hvor sundhedsfaglig ledelse og generel ledelse mikses til hybride ledelsesformer......Artiklen indeholder et litteraturbaseret studium af ledelsesformer i sygehuse, hvor sundhedsfaglig ledelse og generel ledelse mikses til hybride ledelsesformer...

  4. Testing hybrid natural inflation with BICEP2

    Energy Technology Data Exchange (ETDEWEB)

    Carrillo-González, Mariana [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apdo. Postal 48-3, 62251 Cuernavaca, Morelos (Mexico); Germán, Gabriel, E-mail: gabriel@fis.unam.mx [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apdo. Postal 48-3, 62251 Cuernavaca, Morelos (Mexico); Herrera-Aguilar, Alfredo [Departamento de Física, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, CP 09340, México D.F. (Mexico); Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo, Edificio C-3, Ciudad Universitaria, CP 58040, Morelia, Michoacán (Mexico); Hidalgo, Juan Carlos [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apdo. Postal 48-3, 62251 Cuernavaca, Morelos (Mexico); Sussman, Roberto A. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apdo. Postal 70-543, 04510 México D.F. (Mexico)

    2014-06-27

    We analyse Hybrid Natural Inflation in view of the recent results for the tensor index reported by BICEP2. We find that it predicts a large running of the scalar spectrum which is potentially detectable by large scale structure through measurements of clustering of galaxies in combination with CMB data and by 21 cm forest observations. The running of the running is also relatively large becoming close to 10{sup −2}. Along the way, we find general consistency relations at which observables are subject if the slow-roll approximation is imposed. Failure to satisfy these equations by the values obtained for the observables in surveys would be a failure of the slow-roll approximation itself.

  5. Effect of recombinant-LH and hCG in the absence of FSH on in vitro maturation (IVM) fertilization and early embryonic development of mouse germinal vesicle (GV)-stage oocytes.

    Science.gov (United States)

    Dinopoulou, Vasiliki; Drakakis, Peter; Kefala, Stella; Kiapekou, Erasmia; Bletsa, Ritsa; Anagnostou, Elli; Kallianidis, Konstantinos; Loutradis, Dimitrios

    2016-06-01

    During in vitro maturation (IVM), intrinsic and extrinsic factors must co-operate properly in order to ensure cytoplasmic and nuclear maturation. We examined the possible effect of LH/hCG in the process of oocyte maturation in mice with the addition of recombinant LH (r-LH) and hCG in our IVM cultures of mouse germinal vesicle (GV)-stage oocytes. Moreover, the effects of these hormones on fertilization, early embryonic development and the expression of LH/hCG receptor were examined. Nuclear maturation of GV-stage oocytes was evaluated after culture in the presence of r-LH or hCG. Fertilization rates and embryonic development were assessed after 24h. Total RNA was isolated from oocytes of different stages of maturation and from zygotes and embryos of different stages of development in order to examine the expression of LH/hCG receptor, using RT-PCR. The in vitro nuclear maturation rate of GV-stage oocytes that received hCG was significantly higher compared to the control group. Early embryonic development was increased in the hCG and LH cultures of GV oocytes when LH was further added. The LH/hCG receptor was expressed in all stages of in vitro matured mouse oocytes and in every stage of early embryonic development. Addition of hCG in IVM cultures of mouse GV oocytes increased maturation rates significantly. LH, however, was more beneficial to early embryonic development than hCG. This suggests a promising new technique in basic science research or in clinical reproductive medicine. Copyright © 2016 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  6. Resin Catalyst Hybrids

    Institute of Scientific and Technical Information of China (English)

    S. Asaoka

    2005-01-01

    @@ 1Introduction: What are resin catalyst hybrids? There are typically two types of resin catalyst. One is acidic resin which representative is polystyrene sulfonic acid. The other is basic resin which is availed as metal complex support. The objective items of this study on resin catalyst are consisting of pellet hybrid, equilibrium hybrid and function hybrid of acid and base,as shown in Fig. 1[1-5].

  7. Mesoscale hybrid calibration artifact

    Science.gov (United States)

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  8. Flux consumption, current ramp-up and current diffusion in Tore Supra non-inductive Lower Hybrid scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Kazarian, F.; Litaudon, X.; Moreau, D.; Arslanbekov, R.; Hoang, G.T.; Joffrin, E.; Peysson, Y.; Allibert, J.P.; Ane, J.M.; Bremond, S. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee

    1995-12-31

    The main objective of the Lower Hybrid (LH) experiments performed on Tore Supra is to provide large flux savings for long pulse operation while controlling the plasma current density profile. This goal will be best achieved by applying LH wave directly during the current ramp-up phase. Experiments have been performed where a large fraction of the current is driven non-inductively during the ramp-up phase. A theoretical flux consumption scaling is presented and compared to experimental data. The time evolutions of the current density profiles are analysed with a new current diffusion code (CRONOS). In view to achieve fully non-inductive current drive discharges in a fast, systematic and reproducible way, experiments where the primary voltage is imposed have been carried out. In a complementary approach, an appropriate transformer flux feedback scheme has been also studied. (author) 6 refs.; 6 figs.

  9. Realizing the Hybrid Library.

    Science.gov (United States)

    Pinfield, Stephen; Eaton, Jonathan; Edwards, Catherine; Russell, Rosemary; Wissenburg, Astrid; Wynne, Peter

    1998-01-01

    Outlines five projects currently funded by the United Kingdom's Electronic Libraries Program (eLib): HyLiFe (Hybrid Library of the Future), MALIBU (MAnaging the hybrid Library for the Benefit of Users), HeadLine (Hybrid Electronic Access and Delivery in the Library Networked Environment), ATHENS (authentication scheme), and BUILDER (Birmingham…

  10. Homoploid hybrid expectations

    Science.gov (United States)

    Homoploid hybrid speciation occurs when a stable, fertile, and reproductively isolated lineage results from hybridization between two distinct species without a change in ploidy level. Reproductive isolation between a homoploid hybrid species and its parents is generally attained via chromosomal re...

  11. Hybrid armature projectile

    Science.gov (United States)

    Hawke, Ronald S.; Asay, James R.; Hall, Clint A.; Konrad, Carl H.; Sauve, Gerald L.; Shahinpoor, Mohsen; Susoeff, Allan R.

    1993-01-01

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasama blowby.

  12. Intraply Hybrid Composite Design

    Science.gov (United States)

    Chamis, C. C.; Sinclair, J. H.

    1986-01-01

    Several theoretical approaches combined in program. Intraply hybrid composites investigated theoretically and experimentally at Lewis Research Center. Theories developed during investigations and corroborated by attendant experiments used to develop computer program identified as INHYD (Intraply Hybrid Composite Design). INHYD includes several composites micromechanics theories, intraply hybrid composite theories, and integrated hygrothermomechanical theory. Equations from theories used by program as appropriate for user's specific applications.

  13. Hybrid quantum information processing

    Energy Technology Data Exchange (ETDEWEB)

    Furusawa, Akira [Department of Applied Physics, School of Engineering, The University of Tokyo (Japan)

    2014-12-04

    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  14. Impact of resonant magnetic perturbations on zonal modes, drift-wave turbulence and the L-H transition threshold

    Science.gov (United States)

    Leconte, M.; Diamond, P. H.; Xu, Y.

    2014-01-01

    We study the effects of resonant magnetic perturbations (RMPs) on turbulence, flows and confinement in the framework of resistive drift-wave turbulence. This work was motivated, in parts, by experiments reported at the IAEA 2010 conference (Xu et al 2011 Nucl. Fusion 51 062030) which showed a decrease of long-range correlations during the application of RMPs. We derive and apply a zero-dimensional predator-prey model coupling the drift-wave-zonal-mode system (Leconte and Diamond 2012 Phys. Plasmas 19 055903) to the evolution of mean quantities. This model has both density-gradient drive and RMP amplitude as control parameters and predicts a novel type of transport bifurcation in the presence of RMPs. This model allows a description of the full L-H transition evolution with RMPs, including the mean sheared flow evolution. The key results are the following: (i) the L-I and I-H power thresholds both increase with RMP amplitude |\\tilde b_x| , the relative increase of the L-I threshold scales as \\Delta P_LI \\propto |\\tilde b_x|^2 \

  15. Impact of Resonant Magnetic Perturbations on Zonal Modes, Drift-Wave Turbulence and the L-H Transition Threshold

    CERN Document Server

    Leconte, M; Xu, Y

    2013-01-01

    We study the effects of Resonant Magnetic Perturbations (RMPs) on turbulence, flows and confinement in the framework of resistive drift-wave turbulence. This work was motivated, in parts, by experiments reported at the IAEA 2010 conference [Y. Xu {\\it et al}, Nucl. Fusion \\textbf{51}, 062030] which showed a decrease of long-range correlations during the application of RMPs. We derive and apply a zero-dimensional predator-prey model coupling the Drift-Wave Zonal Mode system [M. Leconte and P.H. Diamond, Phys. Plasmas \\textbf{19}, 055903] to the evolution of mean quantities. This model has both density gradient drive and RMP amplitude as control parameters and predicts a novel type of transport bifurcation in the presence of RMPs. This model allows a description of the full L-H transition evolution with RMPs, including the mean sheared flow evolution. The key results are: i) The L-I and I-H power thresholds \\emph{both} increase with RMP amplitude $|\\bx|$, the relative increase of the L-I threshold scales as $\\D...

  16. Preparative separation of gallocatechin gallate from Camellia ptilophylla using macroporous resins followed by sephadex LH-20 column chromatography.

    Science.gov (United States)

    Li, Kaikai; Zhou, Xuelin; Liu, Cheuk-Lun; Yang, Xiaorong; Han, Xiaoqiang; Shi, Xianggang; Song, Xiaohong; Ye, Chuangxing; Ko, Chun-hay

    2016-02-01

    Gallocatechin gallate (GCG) possesses multiple potential biological activities. However, the content of GCG in traditional green tea is too low which limits its in-depth pharmacological research and application. In the present study, a simple, efficient and environment-friendly chromatographic separation method was developed for preparative enrichment and separation of GCG from cocoa tea (Camellia ptilophylla) which contains high content of GCG. In the first step, the adsorption properties of selected resins were evaluated, and XAD-7HP resin was chosen by its adsorption and desorption properties for GCG. In order to maximize column efficiency for GCG collection, the operating parameters (e.g., flow rate, ethanol concentration, and bed height) were optimized. We found that the best combination was the feed concentration at 20mg/mL, flow rate at 0.75 BV/h and the ratio of diameter to bed heights as 1:12. Under these conditions, the purity of GCG was 45% with a recovery of 89%. In order to obtain pure target, a second step was established using column chromatography with sephadex LH-20 gel and 55% ethanol-water solution as eluent. After this step, the purity of the GCG was 91% with a recovery of 68% finally.

  17. Ab initio molecular orbital calculations of electronic couplings in the LH2 bacterial light-harvesting complex of Rps. acidophila

    Energy Technology Data Exchange (ETDEWEB)

    Scholes, G.D.; Fleming, G.R. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley National Lab., CA (United States). Physical Biosciences Div.; Gould, I.R. [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Chemistry; Cogdell, R.J. [Univ. of Glasgow (United Kingdom). Div. of Biochemistry and Molecular Biology

    1999-04-01

    The results of ab initio molecular orbital calculations of excited states and electronic couplings (for energy transfer) between the B800 and B850 bacteriochlorophyll a (Bchl) chromophores in the peripheral light-harvesting complex (LH2) of the purple photosynthetic bacterium Rhodopseudomonas acidophila are reported. Electronic couplings are estimated from supermolecule calculations of Bchl dimers using the Ci-singles methodology and 3-21G{sup *} or 6-31G{sup *} basis sets. A scheme for dissecting the coupling into contributions from the Coulombic coupling and the short-range coupling (i.e., dependent on interchromophore orbital overlap) is reported. B850 couplings are calculated to be [total (Coulombic + short)]: intrapolypeptide dimer 320 (265 + 55) cm{sup {minus}1} and interpolypeptide dimer 255 (195 + 60) cm{sup {minus}1} at the CIS/6-31G{sup *} level. These results differ significantly from those estimated using the point dipole approximation. The effect of including Mg ligands (His residues) and H-bonding residues (Trp and Tyr) is also investigated. The consequences for superradiance and energy transfer dynamics and mechanism are discussed.

  18. PERBAIKAN KEBIJAKAN PENGENDALIAN PERSEDIAAN JUST IN TIME KOMPONEN PRODUK MAIN FLOOR SIDE LH PADA PT GAYA MOTOR

    Directory of Open Access Journals (Sweden)

    Bella Suciana Istiqomah

    2015-06-01

    Full Text Available PT . Gaya Motor is a manufacturing company that is engaged in the assembly and production of automotive components incorporated in the group of PT Astra International.Perusahaan implement inventory control system Just In Time.Kanban’s supplier with safety stock of 0.5 days plus a safety stock of 0.5 extra days beyond the kanban. The study was conducted on the material supply products Main Floor Side LH SA - 001 , SA - 002 , SA - 003 , SA - 004 , SA - 005 , SA - 006 , SA - 007 , SA - 008 and SA - 009. Problems faced by the company are the high amount of inventory caused by inaccurate inventory systems and fault current in raw material procurement procedures. The purpose of this study was to evaluate the company's current inventory control system and propose improvements inventory control system that can minimize inventory costs compared to the cost of inventory at the company's current inventory system.Kanban inventory method supplier company currently has a total cost of inventory of Rp 318.861.462,00. Supplier kanban inventory control methods with safety stock kanban 0.1 days has a total cost of inventory of Rp 158.703.378,00. Inventory control methods Two - Bin Replenishment has a total inventory cost of Rp 98.497.214,00. From the results of these calculations, the minimum inventory cost obtained by using the method of inventory Two - Bin Replenishment, and made proposals related to changes in inventory control system.

  19. Probing energy transfer events in the light harvesting complex 2 (LH2) of Rhodobacter sphaeroides with two-dimensional spectroscopy.

    Science.gov (United States)

    Fidler, Andrew F; Singh, Ved P; Long, Phillip D; Dahlberg, Peter D; Engel, Gregory S

    2013-10-21

    Excitation energy transfer events in the photosynthetic light harvesting complex 2 (LH2) of Rhodobacter sphaeroides are investigated with polarization controlled two-dimensional electronic spectroscopy. A spectrally broadened pulse allows simultaneous measurement of the energy transfer within and between the two absorption bands at 800 nm and 850 nm. The phased all-parallel polarization two-dimensional spectra resolve the initial events of energy transfer by separating the intra-band and inter-band relaxation processes across the two-dimensional map. The internal dynamics of the 800 nm region of the spectra are resolved as a cross peak that grows in on an ultrafast time scale, reflecting energy transfer between higher lying excitations of the B850 chromophores into the B800 states. We utilize a polarization sequence designed to highlight the initial excited state dynamics which uncovers an ultrafast transfer component between the two bands that was not observed in the all-parallel polarization data. We attribute the ultrafast transfer component to energy transfer from higher energy exciton states to lower energy states of the strongly coupled B850 chromophores. Connecting the spectroscopic signature to the molecular structure, we reveal multiple relaxation pathways including a cyclic transfer of energy between the two rings of the complex.

  20. Lower Hybrid Current Drive Experiments on Alcator C-Mod: Comparison with Theory and Simulation

    Science.gov (United States)

    Bonoli, Paul

    2007-11-01

    Recently, lower hybrid current drive (LHCD) experiments have been carried out on Alcator C-Mod using an RF system consisting of 12 klystrons at 4.6 GHz, feeding a 4 x 22 waveguide array. Up to 900 kW of LH power has been coupled in the range1.6 PLH 0.3 [1]. We have simulated the LH current drive in these discharges using the combined ray tracing / 3D (r, v, v//) Fokker Planck code GENRAY -- CQL3D [2] and found similar current drive efficiencies. Measurements of nonthermal x-ray emission and electron cyclotron emission (ECE) confirm the presence of a significant fast electron population that varies with waveguide phasing and plasma density. Studies are currently underway to investigate the role of fast electron diffusion and full-wave effects such as diffractional broadening in determining the spatial and velocity space structure of the nonthermal electrons. The 3D (r, v, v//) electron distribution function from CQL3D has been used in synthetic diagnostic codes to simulate the measured hard x-ray and ECE emissions. Fast electron diffusion times have been inferred from x-ray data by employing a radial diffusion operator in CQL3D and determining the fast electron diffusivities that are required to reproduce the experimentally observed profiles of hard x-ray emission. Finally, we have been performing full-wave LH field simulations using the massively parallel TORIC --LH solver [3] in order to assess spatial and spectral broadening of the incident wave front that can result from diffraction and wave focusing effects. [1] R. Parker, Bull. Am. Phys. Soc. 51, 20 (2006). [2] R.W. Harvey and M. McCoy, ``The CQL3D Fokker Planck Code,'' Proc. IAEA Tech. Comm. Meeting on Simulation and Modeling of Thermonuclear Plasmas, Montreal, Canada, 1992. [3] J. C. Wright et al., Nucl. Fusion 45, 1411 (2005).