Sample records for rubidium d2 line

  1. Effect of photoions on the line shape of the Foerster resonance lines and microwave transitions in cold rubidium Rydberg atoms

    Energy Technology Data Exchange (ETDEWEB)

    Tretyakov, D. B.; Beterov, I. I.; Entin, V. M.; Yakshina, E. A.; Ryabtsev, I. I., E-mail: [Russian Academy of Sciences, Institute of Semiconductor Physics, Siberian Branch (Russian Federation); Dyubko, S. F.; Alekseev, E. A.; Pogrebnyak, N. L. [National Academy of Sciences of Ukraine, Institute of Radio Astronomy (Ukraine); Bezuglov, N. N. [St. Petersburg State University (Russian Federation); Arimondo, E. [Universita di Pisa (Italy)


    Experiments are carried out on the spectroscopy of the Foerster resonance lines Rb(37P) + Rb(37P) {yields} Rb(37S) + Rb(38S) and microwave transitions nP {yields} n Prime S, n Prime D between Rydberg states of cold rubidium atoms in a magneto-optical trap (MOT). Under ordinary conditions, all spectra exhibit a linewidth of 2-3 MHz irrespective of the interaction time between atoms or between atoms and microwave radiation, although the limit resonance width should be determined by the inverse interaction time. The analysis of experimental conditions has shown that the main source of line broadening is the inhomogeneous electric field of cold photoions that are generated under the excitation of initial nP Rydberg states by broadband pulsed laser radiation. The application of an additional electric-field pulse that rapidly extracts photoions produced by a laser pulse leads to a considerable narrowing of lines of microwave resonances and the Foerster resonance. Various sources of line broadening in cold Rydberg atoms are analyzed.

  2. Magnetic field dependent intensity variation in the hyperfine split Rb D1 and D2 lines (United States)

    Hu, Jianping; Ummal Momeen, M.


    We present the variation of intensity in Doppler-free hyperfine lines for rubidium atoms with the application of magnetic field. Different polarization configurations have been studied systematically with varying magnetic fields. There is a significant increase in the intensity variation with applied magnetic field related to different polarization configurations. These variations are explained with the theoretical calculations. The calculations are performed by adopting Nakayama's four level model with the varying magnetic field induced transition probability.

  3. Coherent optical transients observed in rubidium atomic line filtered Doppler velocimetry experiments (United States)

    Fajardo, Mario E.; Molek, Christopher D.; Vesely, Annamaria L.


    We report the first successful results from our novel Rubidium Atomic Line Filtered (RALF) Doppler velocimetry apparatus, along with unanticipated oscillatory signals due to coherent optical transients generated within pure Rb vapor cells. RALF is a high-velocity and high-acceleration extension of the well-known Doppler Global Velocimetry (DGV) technique for constructing multi-dimensional flow velocity vector maps in aerodynamics experiments [H. Komine, U.S. Patent No. 4,919,536 (24 April 1990)]. RALF exploits the frequency dependence of pressure-broadened Rb atom optical absorptions in a heated Rb/N2 gas cell to encode the Doppler shift of reflected near-resonant (λ0 ≈ 780.24 nm) laser light onto the intensity transmitted by the cell. The present RALF apparatus combines fiber optic and free-space components and was built to determine suitable operating conditions and performance parameters for the Rb/N2 gas cells. It yields single-spot velocities of thin laser-driven-flyer test surfaces and incorporates a simultaneous Photonic Doppler Velocimetry (PDV) channel [Strand et al., Rev. Sci. Instrum. 77, 083108 (2006)] for validation of the RALF results, which we demonstrate here over the v = 0 to 1 km/s range. Both RALF and DGV presume the vapor cells to be simple Beer's Law optical absorbers, so we were quite surprised to observe oscillatory signals in experiments employing low pressure pure Rb vapor cells. We interpret these oscillations as interference between the Doppler shifted reflected light and the Free Induction Decay (FID) coherent optical transient produced within the pure Rb cells at the original laser frequency; this is confirmed by direct comparison of the PDV and FID signals. We attribute the different behaviors of the Rb/N2 vs. Rb gas cells to efficient dephasing of the atomic/optical coherences by Rb-N2 collisions. The minimum necessary N2 buffer gas density ≈0.3 amagat translates into a smallest useful velocity range of 0 to 2 km/s, which can

  4. Temperature Dependent Rubidium Helium Line Shapes and Fine Structure Mixing Rates (United States)


    earlier by used by Brown [21]. Using the equations derived earlier for a pulsed experiment it can be shown that the the decay is an exponential decay on the...of C 133 s, R 8 7, 8 5 b, and N 23 a with Uncertainties 0.2 ppb”. Physical Review Letters, 83(22):4510, 1999. [21] Brown , Kirk C. and Glen P. Perram...Hindmarsh, William Russell and Judith M Farr. “Collision broadening of spectral lines by neutral atoms”. Progress in Quantum Electronics, 2:141–214

  5. Temperature Dependent Rubidium-Helium Line Shapes and Fine Structure Mixing Rates (United States)


    earlier by used by Brown [21]. Using the equations derived earlier for a pulsed experiment it can be shown that the the decay is an exponential decay on the...of C 133 s, R 8 7, 8 5 b, and N 23 a with Uncertainties 0.2 ppb”. Physical Review Letters, 83(22):4510, 1999. [21] Brown , Kirk C. and Glen P. Perram...Hindmarsh, William Russell and Judith M Farr. “Collision broadening of spectral lines by neutral atoms”. Progress in Quantum Electronics, 2:141–214

  6. Preparation of 5.6dB vacuum squeezing on 795nm rubidium D1 line via an OPO (Conference Presentation) (United States)

    Wang, Junmin; Han, Yashuai; Wen, Xin; Yang, Baodong; Wang, Yanhua; He, Jun


    We report on experimental preparation of the second-harmonic-wave laser and the single-mode squeezed vacuum state of 795 nm (rubidium atom D1 line) with periodically-poled KTiOPO4 (PPKTP) bulk crystals. By using a four-mirror bow-tie type ring doubling cavity we achieved ~111 mW of continuous-wave single-frequency ultra-violet (UV) laser radiation at 397.5 nm with ~191 mW of 795 nm fundamental-wave laser input. The corresponding doubling efficiency is 58.1%. To our knowledge, this is the highest doubling efficiency at 795 nm so far. Employing the 397.5 nm UV laser as a pump source of an optical parametric oscillator (OPO) with a PPKTP crystal, we achieved 5.6 dB of 795 nm single-mode squeezed vacuum output at analyzing frequency of 2 MHz. To our knowledge, this is the highest squeezing level of 795 nm single-mode squeezed vacuum so far. We analyzed the pump power dependence of the squeezing level, and concluded that UV laser induced losses of PPKTP crystal are main limiting factors for further improving the squeezing level. The generated 795 nm vacuum squeezing has huge potential applications in quantum memory and ultra-precision measurement with rubidium atoms.

  7. Polarization spectroscopy and magnetically-induced dichroism of the potassium D2 lines

    CERN Document Server

    Pahwa, K; Goldwin, J


    We study modulation-free methods for producing sub-Doppler, dispersive line shapes for laser stabilization near the potassium D2 transitions at 767 nm. Polarization spectroscopy is performed and a comparison is made between the use of a mirror or beam splitter for aligning the counter-propagating pump and probe beams. Conventional magnetically-induced dichroism is found to suffer from a small dispersion and large background offset. We therefore introduce a modified scheme, using two spatially separated pump-probe beam pairs. Finally we compare our results to methods using phase modulation and heterodyne detection.

  8. Genome-wide comparative transcriptome analysis of CMS-D2 and its maintainer and restorer lines in upland cotton. (United States)

    Wu, Jianyong; Zhang, Meng; Zhang, Bingbing; Zhang, Xuexian; Guo, Liping; Qi, Tingxiang; Wang, Hailin; Zhang, Jinfa; Xing, Chaozhu


    Cytoplasmic male sterility (CMS) conferred by the cytoplasm from Gossypium harknessii (D2) is an important system for hybrid seed production in Upland cotton (G. hirsutum). The male sterility of CMS-D2 (i.e., A line) can be restored to fertility by a restorer (i.e., R line) carrying the restorer gene Rf1 transferred from the D2 nuclear genome. However, the molecular mechanisms of CMS-D2 and its restoration are poorly understood. In this study, a genome-wide comparative transcriptome analysis was performed to identify differentially expressed genes (DEGs) in flower buds among the isogenic fertile R line and sterile A line derived from a backcross population (BC 8 F 1 ) and the recurrent parent, i.e., the maintainer (B line). A total of 1464 DEGs were identified among the three isogenic lines, and the Rf1-carrying Chr_D05 and its homeologous Chr_A05 had more DEGs than other chromosomes. The results of GO and KEGG enrichment analysis showed differences in circadian rhythm between the fertile and sterile lines. Eleven DEGs were selected for validation using qRT-PCR, confirming the accuracy of the RNA-seq results. Through genome-wide comparative transcriptome analysis, the differential expression profiles of CMS-D2 and its maintainer and restorer lines in Upland cotton were identified. Our results provide an important foundation for further studies into the molecular mechanisms of the interactions between the restorer gene Rf1 and the CMS-D2 cytoplasm.

  9. Inhibition of mutant IDH1 decreases D-2-HG levels without affecting tumorigenic properties of chondrosarcoma cell lines. (United States)

    Suijker, Johnny; Oosting, Jan; Koornneef, Annemarie; Struys, Eduard A; Salomons, Gajja S; Schaap, Frank G; Waaijer, Cathelijn J F; Wijers-Koster, Pauline M; Briaire-de Bruijn, Inge H; Haazen, Lizette; Riester, Scott M; Dudakovic, Amel; Danen, Erik; Cleton-Jansen, Anne-Marie; van Wijnen, Andre J; Bovée, Judith V M G


    Mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 are found in a subset of benign and malignant cartilage tumors, gliomas and leukaemias. The mutant enzyme causes the production of D-2-hydroxyglutarate (D-2-HG), affecting CpG island and histone methylation. While mutations in IDH1/2 are early events in benign cartilage tumors, we evaluated whether these mutations play a role in malignant chondrosarcomas. Compared to IDH1/2 wildtype cell lines, chondrosarcoma cell lines harboring an endogenous IDH1 (n=3) or IDH2 mutation (n=2) showed up to a 100-fold increase in intracellular and extracellular D-2-HG levels. Specific inhibition of mutant IDH1 using AGI-5198 decreased levels of D-2-HG in a dose dependent manner. After 72 hours of treatment one out of three mutant IDH1 cell lines showed a moderate decrease in viability , while D-2-HG levels decreased >90%. Likewise, prolonged treatment (up to 20 passages) did not affect proliferation and migration. Furthermore, global gene expression, CpG island methylation as well as histone H3K4, -9, and -27 trimethylation levels remained unchanged. Thus, while IDH1/2 mutations cause enchondroma, malignant progression towards central chondrosarcoma renders chondrosarcoma growth independent of these mutations. Thus, monotherapy based on inhibition of mutant IDH1 appears insufficient for treatment of inoperable or metastasized chondrosarcoma patients.

  10. Kinetic-Energy Distribution of D(2p) Atoms from Analysis of the D Lyman-Alpha Line Profile (United States)

    Ciocca, M.; Ajello, Joseph M.; Liu, Xianming; Maki, Justin


    The kinetic-energy distribution of D(2p) atoms resulting from electron-impact dissociation of D2 has been measured. A high-resolution vacuum ultraviolet spectrometer was employed for the first measurement of the D Lyman-alpha (D L(alpha)) emission line profiles at 20- and 100-eV excitation energies. Analysis of the deconvoluted line profile of D L(alpha) at 100 eV reveals the existence of a narrow line central peak of 29+/-2 mA full width at half maximum and a broad pedestal wing structure about 190 mA wide. The wings of the line can be used to determine the fast atom distribution. The wings of D L(alpha) arise from dissociative excitation of a series of doubly excited states that cross the Franck-Condon region between 23 and 40 eV. The fast atom distribution at 100-eV electron impact energy spans the energy range from 1 to 10 eV with a peak value near 6 eV. Slow D(2p) atoms characterized by a distribution function with peak energy near 100 meV produce the central peak profile, which is nearly independent of the impact energy. The deconvoluted line profiles of the central peak at 20 eV for dissociative excitation of D2 and H2 are fitted with an analytical function for use in calibration of space flight instrumentation equipped with a D/H absorption cell. The kinetic-energy and line profile results are compared to similar measurements for H2. The absolute cross sections for the line center (slow atoms) and wings (fast atoms) and total emission line profile were measured from threshold to 400 eV. Analytical model coefficients are given for the energy dependence of the measured slow atom cross section.

  11. Antiproliferative Activity of Double Point Modified Analogs of 1,25-Dihydroxyvitamin D2 Against Human Malignant Melanoma Cell Lines

    Directory of Open Access Journals (Sweden)

    Anna Piotrowska


    Full Text Available Vitamin D is a lipid soluble steroid hormone with pleiotropic biological properties, including regulation of cell proliferation, differentiation and apoptosis. As to these desirable anticancer actions, 1,25-dihydroxyvitamins D and analogs have been reported to inhibit the proliferation and to induce differentiation of a wide variety of cancer cell types, including human malignant melanoma. However, there is a need for novel and more efficacious vitamin D analogs, and how best to design such is still an open issue. A series of double point modified (DPM analogs of 1,25-dihydroxyvitamin D2 (1,25(OH2D2 induced differentiation of the vitamin D receptor (VDR positive A375 and VDR negative SK-MEL 188b human malignant melanoma cell lines. Surprisingly, the dose of 1,25(OH2D2 required to inhibit the proliferation of the A375 melanoma cell line by was several fold lower than that required in the case of 1,25(OH2D3. To evaluate the impact of the modification in the side chain (additional 22-hydroxyl and in the A-ring (5,6-trans modification, the regular side-chain of vitamin D2 or D3 was retained in the structure of our analogs. As expected, 5,6-trans modification was advantageous to enhancing the anti-proliferative activity of analogs, but not as a single point modification (SPM. Very unexpectedly, the additional 22-hydroxyl in the side-chain reduced significantly the anti-proliferative activity of both the natural and 5,6-trans series analogs. Finally, an induction of pigmentation in melanoma SK-MEL 188b cells was observed to sensitized cells to the effect of vitamin D analogs.

  12. One step beyond the electric dipole approximation: An experiment to observe the 5p → 6p forbidden transition in atomic rubidium (United States)

    Ponciano-Ojeda, F.; Hernández-Gómez, S.; Mojica-Casique, C.; Ruiz-Martínez, E.; López-Hernández, O.; Colín-Rodríguez, R.; Ramírez-Martínez, F.; Flores-Mijangos, J.; Sahagún, D.; Jáuregui, R.; Jiménez-Mier, J.


    An advanced undergraduate experiment to study the 5 P 3 / 2 → 6 P 3 / 2 electric quadrupole transition in rubidium atoms is presented. The experiment uses two external cavity diode lasers, one operating at the D2 rubidium resonance line and the other built with commercial parts to emit at 911 nm. The lasers produce the 5 s → 5 p → 6 p excitation sequence in which the second step is the forbidden transition. Production of atoms in the 6 P 3 / 2 state is observed by detection of the 420 nm fluorescence that results from electric dipole decay into the ground state. Lines whose widths are significantly narrower than the Doppler width are used to study the hyperfine structure of the 6 P 3 / 2 state in rubidium. The spectra illustrate characteristics unique to electric dipole forbidden transitions, like the electric quadrupole selection rules; they are also used to show general aspects of two-color laser spectroscopy such as velocity selection and hyperfine pumping.

  13. Study of the 5p3/2 -> 6p3/2 electric dipole forbidden transition in atomic rubidium using optical-optical double resonance spectroscopy

    CERN Document Server

    Ponciano-Ojeda, Francisco; López-Hernández, Oscar; Mojica-Casique, Cristian; Colín-Rodríguez, Ricardo; Ramírez-Martínez, Fernando; Flores-Mijangos, Jesús; Sahagún, Daniel; Jáuregui, Rocío; Jiménez-Mier, José


    Direct evidence of excitation of the 5p3/2 -> 6p3/2 electric dipole forbidden transition in atomic rubidium is presented. The experiments were performed in a room temperature rubidium cell with continuous wave extended cavity diode lasers. Optical-optical double resonance spectroscopy with counterpropagating beams allows the detection of the non-dipole transition free of Doppler broadening. The 5p3/2 state is prepared by excitation with a laser locked to the maximum F cyclic transition of the D2 line, and the forbidden transition is produced by excitation with a 911 nm laser. Production of the forbidden transition is monitored by detection of the 420 nm fluorescence that results from decay of the 6p3/2 state. Spectra with three narrow lines (~ 13 MHz FWHM) with the characteristic F - 1, F and F + 1 splitting of the 6p3/2 hyperfine structure in both rubidium isotopes were obtained. The results are in very good agreement with a direct calculation that takes into account the 5s -> 5p3/2 preparation dynamics, the...

  14. Kinetic Energy Distribution of D(2p) Atoms From Analysis of the D Lyman-a Line Profile (United States)

    Ciocca, Marco; Ajello, Joseph M.; Liu, Xianming; Maki, Justin


    The absolute cross sections of the line center (slow atoms) and wings (fast atoms) and total emission line profile were measured from threshold to 400 eV. Analytical model coeffiecients are given for the energy dependence of the measured slow atom cross section.

  15. Tuning single GaAs quantum dots in resonance with a rubidium vapor

    NARCIS (Netherlands)

    Akopian, N.; Perinetti, U.; Wang, L.; Rastelli, A.; Schmidt, O.G.; Zwiller, V.


    We study single GaAs quantum dots with optical transitions that can be brought into resonance with the widely used D2 transitions of rubidium atoms. We achieve resonance by Zeeman or Stark shifting the quantum dot levels. We discuss an energy stabilization scheme based on the absorption of quantum

  16. On-line SPE sample treatment as a tool for method automatization and detection limits reduction: Quantification of 25-hydroxyvitamin D3/D2. (United States)

    Palaiogiannis, Dimitrios; Bekou, Evangelia; Pazaitou-Panayiotou, Kalliopi; Samanidou, Victoria; Tsakalof, Andreas


    The development and approbation of new, automated UHPLC-DAD method for the quantification of 25-hydroxyvitamin D3/D2 (25OH-D3/D2) metabolites in plasma/serum for the evaluation of patient's vitamin D status are presented. The method was developed on the Ultimate 3000 UHPLC dual gradient system supplied with the on-line SPE-concentration column coupled through six port switching valve to analytical column. This configuration and materials selected enable large volume sample injection (500μL) and on-line sample preconcentration, clean up and subsequent selective metabolites transfer onto the analytical column. The new method abrogates main conventional time consuming and error source off-line steps of analysis and thus simplifies analysis. The large volume injection increases the sensitivity of instrumental analysis by about ten-fold on-line pre-concentration of metabolites. The instrument response is linear (R>0.99) in the investigated concentration range 10-100ngmL-1 which covers all the possible vitamin D status from serious deficiency (method detection limits (S/N=3) are LOD (25OH-D3)=0.94ngmL-1 and LOD (25OH-D2)=2.4ngmL-1. The method performance was assessed with the use of certified reference samples and perfect agreement between certified and measured values is demonstrated. The method was applied to human samples previously analyzed for total vitamin D by Competitive Protein-binding assay and findings of the two methods are compared. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. The effect of ghrelin on Kiss-1 and KissR gene transcription and insulin secretion in rat islets of Langerhans and CRI-D2 cell line

    Directory of Open Access Journals (Sweden)

    Mandana Mahmoodzaeh Sagheb


    Full Text Available Objective(s: Ghrelin is a peptide hormone that has been shown to have numerous central and peripheral effects. The central effects including GH secretion, food intake, and energy homeostasis are partly mediated by Kiss1- KissR signaling pathway. Ghrelin and its receptor are also expressed in the pancreatic islets. Ghrelin is one of the key metabolic factors controlling insulin secretion from the islets of Langerhans. We hypothesize that the inhibitory effect of ghrelin on KiSS-1 and KissR in the islet cells may be similar to the same inhibitory effect of ghrelin in the hypothalamus. Materials and Methods: To investigate the effect of ghrelin, we isolated the islets from adult male rats by collagenase and cultured CRI-D2 cell lines. Then, we incubated them with different concentrations of ghrelin for 24 hr. After RNA extraction and cDNA synthesis from both islets and CRI-D2 cells, the relative expression of KiSS-1 and KissR was evaluated by means of real-time PCR. Furthermore, we measured the amount of insulin secreted by the islets after incubation in different concentrations of ghrelin and glucose after 1 hr. Besides, we checked the viability of the cells after 24 hr cultivation.  Results: Ghrelin significantly decreased the KiSS-1 and KissR mRNA transcription in rat islets and CRI-D2 cells. Besides, Ghrelin suppressed insulin secretion from pancreatic beta cells and CRI-D2 cells. Conclusion: These findings indicate the possibility that KiSS-1 and KissR mRNA expression is mediator of ghrelin function in the islets of Langerhans.

  18. Extraction of rubidium from natural resources (United States)

    Ertan, Bengü


    Rubidium is a rare alkali metal in the first group of periodic table. It has some exclusive properties like softness, ductility, malleability, strong chemical and photo-emissive activity, low melting point, easy ionization. So it is used many of applications such that optical and laser technology, electronics, telecommunications, biomedical, space technology, academic research especially quantum mechanics-based computing devices. Attention of rubidium in relation to its uses will increase in the near future. Rubidium does not have any mineral that is the main component. It is produced as minor quantities from lithium or cesium-rich minerals and natural brines. However, there are a few researches on the extraction of rubidium from mine tailings. It is difficult extraction or concentration of rubidium from these resources. Because they require a series of physical and chemical treatments and cost expensive. Efficient, cheap and friendly of environment methods for the recovery of this metal are being investigated.

  19. Nonlinear Spectroscopy of Rubidium: An Undergraduate Experiment (United States)

    Jacques, V.; Hingant, B.; Allafort, A.; Pigeard, M.; Roch, J. F.


    In this paper, we describe two complementary nonlinear spectroscopy methods which both allow one to achieve Doppler-free spectra of atomic gases. First, saturated absorption spectroscopy is used to investigate the structure of the 5S[subscript 1/2] [right arrow] 5P[subscript 3/2] transition in rubidium. Using a slightly modified experimental…

  20. Rubidium deficiency in dialysis patients. (United States)

    Canavese, C; DeCostanzi, E; Branciforte, L; Caropreso, A; Nonnato, A; Pietra, R; Fortaner, S; Jacono, F; Angelini, G; Gallieni, M; Fop, F; Sabbioni, E


    Since dialysis has brought long-term survival to uremic patients, we can now speculate on more subtle problems derived from imbalance or sub-optimal regulation of some elements such as trace metals. We focused on the rubidium (Rb) status in dialysis patients (HD), as concerns about its possible deficiency have been raised. Rb in uremic patients was evaluated by: A) serum concentration (graphite furnace atomic absorption spectroscopy) from blood samples of 70 patients on chronic hemodialysis (HD) in comparison with 75 controls; B) tissue concentration (neutron activation analysis) from autopsy or biopsy samples (20) of HD patients in comparison with 21 controls; C) in vivo intradialytic mass balance during standard bicarbonate dialysis in 8 HD patients. A) Serum Rb concentrations in HD patients significantly were lower than in normal controls (304 +/- 81 micrograms/L versus 350 +/- 74 micrograms/L p < 0.001, log-transformed 5.68 +/- 0.28 versus 5.84 +/- 0.20, p < 0.001). Univariate logistic regression analysis found a significantly higher risk of serum Rb < 250-300 and 350 micrograms/L in uremic patients than in controls (Odd ratios or 12.6, 95% CI 2.77-57.04; 4.0, 95% CI 1.92-8.4; 2.08, 95% CI 1.02-4.25, respectively). B) Rb was significantly lower in tissues of HD patients, including brain (2250 +/- 1520 ng/g versus 5490 +/- 1250 ng/g, p = 0.0002) than normal controls. C) Rb was transferred from the patients' blood to the dialysis bath during a standard bicarbonate dialysis session, giving mean intradialytic Rb removal of 4.0 +/- 1.1 mg/session. These results confirm that Rb deficiency may arise in uremic patients, and indicate that diffusive dialysis treatments allow Rb removal which, however, with a standard bicarbonate schedule does not seem to be any greater than that expected with normal urine output (20 mg/week). Further studies are needed to clarify the roles of many factors in this Rb deficiency, including the effects of uremia by itself, pre

  1. D2-tree

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Sioutas, Spyros; Pantazos, Kostas


    We present a new overlay, called the Deterministic Decentralized tree (D2-tree). The D2-tree compares favorably to other overlays for the following reasons: (a) it provides matching and better complexities, which are deterministic for the supported operations; (b) the management of nodes (peers...

  2. Microwave Spectroscopy of Cold Rubidium Atoms


    Entin, V. M.; Ryabtsev, I. I.


    The effect of microwave radiation on the resonance fluorescence of a cloud of cold $^{85}Rb$ atoms in a magnetooptical trap is studied. The radiation frequency was tuned near the hyperfine splitting frequency of rubidium atoms in the 5S ground state. The microwave field induced magnetic dipole transitions between the magnetic sublevels of the 5S(F=2) and 5S(F=3) states, resulting in a change in the fluorescence signal. The resonance fluorescence spectra were recorded by tuning the microwave r...

  3. Strontium-Rubidium Age of an Iron Meteorite. (United States)

    Wasserburg, G J; Burnett, D S; Frondel, C


    The isotopic compositions and concentrations of rubidium and strontium were determined in silicate nodules contained in Weekeroo Station meteorite, a brecciated coarse octahedrite. The strontium had a Sr(87):Sr(86) range from 0.729 to 0.768, showing considerable enrichment in Sr(87) in coinparison with achondrites. Data for six samples of nodules lie on a straight line on the Sr-Rb evolution diagram, with an initial Sr(87):Sr(86) ratio of 0.696 to 0.702; the slope is 0.0674, corresponding to an age of 4.7 x 10(9) years for lambda = 1.39 x 10(-11) year(-1). These data agree with the previously assigned ages for the formation of stony meteorites and the earth; they support the conclusion that the major period of chemical and physical differentiation in the solar system occurred in a narrow interval at about this time. This result disagrees with the Ar(40)-K(40) ages of 5 to 13 x 10(9) years determined from other iron meteorites. A wide variety of isotopic-age investigations now seem experimentally feasible on iron meteorites that contain silicates.

  4. Application Status of Rubidium, Cesium and Research Situation of its Separation from Brine with Solvent Extraction (United States)

    Shi, Zhen; Du, Xuemin; Wang, Shiqiang; Guo, Yafei; Deng, Tianlong


    Rubidium, cesium and its compounds play an important role in traditional and high-tech fields. This paper focuses on the research status of separation rubidium and cesium in brine using solvent extraction, and briefly introduced the characteristics of this method, which can be used to realize industrial production of rubidium and cesium from brine.

  5. A rubidium vapor source for a plasma source for AWAKE (United States)

    Plyushchev, G.; Kersevan, R.; Petrenko, A.; Muggli, P.


    We present the scheme for a rubidium vapor source that is used as a plasma source in the AWAKE plasma wakefield acceleration experiment. The plasma wakefield acceleration process requires a number of stringent parameters for the plasma: electron density adjustable in the (1–10)  ×  10 14 cm‑3 range, 0.25% relative density uniformity, sharp (the beginning the plasma column. We show with analytical and direct simulation Monte Carlo results that the rubidium density in the proposed source should meet these requirements. Laser ionization then transfers the above neutral vapor parameters to the plasma.

  6. Spontaneuos and Parametric Processes in Warm Rubidium Vapours

    Directory of Open Access Journals (Sweden)

    Dąbrowski M.


    Full Text Available Warm rubidium vapours are known to be a versatile medium for a variety of experiments in atomic physics and quantum optics. Here we present experimental results on producing the frequency converted light for quantum applications based on spontaneous and stimulated processes in rubidium vapours. In particular, we study the efficiency of spontaneously initiated stimulated Raman scattering in the Λ-level configuration and conditions of generating the coherent blue light assisted by multi-photon transitions in the diamond-level configuration. Our results will be helpful in search for new types of interfaces between light and atomic quantum memories.

  7. Quenching of excited rubidium (52P) atoms in flames

    NARCIS (Netherlands)

    Hooymayers, H.P.; Nienhuis, G.

    An alternating current photoelectric device (compare the work of Boers,(1) Hooymayers et al(2-4) and Hooymayers(5)) has been used for determining the yield factor p of resonance fluorescence for the infrared rubidium doublet (7800/7947 Å). From the p-values measured in five different hydrogen flames

  8. Sympathetic cooling of ytterbium with rubidium; Sympathetische Kuehlung von Ytterbium mit Rubidium

    Energy Technology Data Exchange (ETDEWEB)

    Tassy, S.


    Within the scope of this thesis, a mixture of ultracold ytterbium and rubidium atoms was experimentally realized and investigated. For these experiments, a novel trap geometry was developed which allows simultaneous trapping and cooling of diamagnetic and paramagnetic atomic species. The main focus was put on the investigation of the interspecies scattering properties, where sympathetic cooling of ytterbium through elastic collisions with rubidium could be demonstrated. In addition, the interspecies scattering length could be determined. In the current configuration the combined trap allows the preparation of up to 2.10{sup 5} atoms of {sup 170}Yb, {sup 171}Yb, {sup 172}Yb, {sup 174}Yb or {sup 176}Yb at a temperature of 40..60 {mu}K and a density in the range of 10{sup 12} cm{sup -3}, and of about 10{sup 7} {sup 87}Rb atoms at a temperature of 25 {mu}K and a density in the range of 5.10{sup 11} cm{sup -3}. Detailed studies of the thermalization of bosonic {sup 170}Yb, {sup 172}Yb, {sup 174}Yb and {sup 176}Yb and of fermionic {sup 171}Yb each with {sup 87}Rb were performed under varying experimental conditions. The deduced total scattering cross section was clearly found to increase with higher mass of the ytterbium isotope. In general, a mass scaling of the scattering properties is in agreement with theoretical models and former experimental work. With the assumption of pure s-wave scattering, which is approximately fulfilled for the given experimental parameters, the interspecies scattering length could be derived from the measured thermalization data and was found to be (in units of the Bohr radius a{sub 0}): {sup 170}Yb-{sup 87}Rb:(18{sup +12}{sub -4})a{sub 0}, {sup 171}Yb-{sup 87}Rb:(25{sup +14}{sub -7})a{sub 0}, {sup 172}Yb-{sup 87}Rb:(33{sup +23}{sub -7})a{sub 0}, {sup 174}Yb-{sup 87}Rb:(83{sup +89}{sub -25})a{sub 0}, {sup 176}Yb-{sup 87}Rb:(127{sup +245}{sub -45})a{sub 0}. (orig./HSI)

  9. Fiber laser system for cesium and rubidium atom interferometry

    CERN Document Server

    Diboune, Clément; Bidel, Yannick; Cadoret, Malo; Bresson, Alexandre


    We present an innovative fiber laser system for both cesium and rubidium manipulation. The architecture is based on frequency conversion of two lasers at 1560 nm and 1878 nm. By taking advantage of existing fiber components at these wavelengths, we demonstrate an all fiber laser system delivering 350 mW at 780 nm for rubidium and 210 mW at 852 nm for cesium. This result highlights the promising nature of such laser system especially for Cs manipulation for which no fiber laser system has been reported. It offers new perspectives for the development of atomic instruments dedicated to onboard applications and opens the way to a new generation of atom interferometers involving three atomic species $^{85}$Rb, $^{87}$Rb and $^{133}$Cs for which we propose an original laser architecture.

  10. Modeling polarization reversal in optically pumped rubidium vapors (United States)

    Dreiling, J. M.; Norrgard, E.; Gay, T. J.


    Rubidium atoms can be polarized by optical pumping with a resonant circularly polarized laser beam. Using Faraday rotation polarimetry [1], we have observed a flip in the sign of the Rb electron polarization when the wavelength of the pump laser is varied over the D1 absorption spectrum. This could occur if F Hitt, and T.J. Gay, Phys. Rev. Lett. 82, 4216 (1999).

  11. The KLM + KLN Auger electron spectrum of rubidium in different matrices (United States)

    Inoyatov, A. Kh; Kovalík, A.; Perevoshchikov, L. L.; Filosofov, D. V.; Vénos, D.; Lee, B. Q.; Ekman, J.; Baimukhanova, A.


    The KLM + KLN Auger electron spectrum of rubidium (Z = 37) emitted in the electron capture decay of radioactive 83Sr in a polycrystalline platinum matrix and also 85Sr in polycrystalline platinum and carbon matrices as well as in an evaporated layer onto a carbon backing were experimentally studied in detail for the first time using a combined electrostatic electron spectrometer. Energies, relative intensities, and natural widths of fifteen basic spectrum components were determined and compared with both theoretical predictions and experimental data for krypton (Z = 36). Relative spectrum line energies obtained from the semi-empirical calculations in intermediate coupling scheme were found to agree within 3σ with the measured values while disagreement with experiment exceeding 3σ was often observed for values obtained from our multiconfiguration Dirac-Hartree-Fock calculations. The absolute energy of the dominant spectrum component given by the semi-empirical approach agrees within 1σ with the measured value. Shifts of +(0.2 ± 0.2) and -(1.9 ± 0.2) eV were measured for the dominant KLM spectrum components between the 85Sr sources prepared by vacuum evaporation on and implanted into the carbon foil, respectively, relative to 85Sr implanted into the platinum foil. A value of (713 ± 2) eV was determined for the energy difference of the dominant components of the KLM + KLN Auger electron spectra of rubidium and krypton generated in the polycrystalline platinum matrix. From the detailed analysis of the measured data and available theoretical results, the general conclusion can be drawn that the proper description of the KLM + KLN Auger electron spectrum for Z around 37 should still be based on the intermediate coupling of angular momenta taking into account relativistic effects.

  12. Time resolved spectroscopic investigation of SiD2 + D2: kinetic study (United States)

    Al-Rubaiey, Najem A.; Walsh, Robin


    Silylenes (silanediyls) have made an important impact on organosilicon chemistry even if it is of more recent foundation than carbenes in organic chemistry and much less complete. These species are highly reactive intermediates. They play a central role in the chemical vapour deposition (CVD) of various silicon-containing thin films which have a technological importance in microelectronics as well as in the dry etching processes of silicon wafers. Spectroscopic methods have been developed to observe these species, a necessary pre-requisite to their direct monitoring. In this work, deuterated phenylsilane precursor, PhSiD3 was chosen for SiD2 because its analogue phenylsilane, PhSiH3 proved to be a good precursor for SiH2 and the high quality decay signals observed revealed that SiD2 be readily detected from PhSiD3 and that if other decomposition pathways (e.g. PhSiD + D2) are occurring, they do not effect measurements of the rate constants for SiD2. The absorption spectrum of SiD2 formed from the flash photolysis of a mixture of PhSiD3 and SF6 at 193nm were found in the region 17384-17391 cm-1 with strong band at 17387.07 cm-1. This single rotational line of pQ1 was chosen to monitor SiD2 removal. Time-resolved studies of SiD2 have been carried out to obtain rate constants for its bimolecular reactions with D2. The reactions were studied over the pressure range 5-100 Torr (in SF6 bath gas) at four temperatures in the range 298-498K. Single decay from 10 photolysis laser shots were averaged and found to give reasonable first-order kinetics fits. Second order kinetics were obtained by pressure dependence of the pseudo first order decay constants and substance D2 pressures within experimental error. The reaction was found to be weakly pressure dependent at all temperatures, consistent with a third-body mediated association process. In addition, SiH2+ H2 reaction is approximately ca. 60% faster than SiD2+D2 reaction. Theoretical extrapolations (using Lindemann

  13. Time resolved spectroscopic investigation of SiD2 + D2: kinetic study

    Directory of Open Access Journals (Sweden)

    Al-Rubaiey Najem A.


    Full Text Available Silylenes (silanediyls have made an important impact on organosilicon chemistry even if it is of more recent foundation than carbenes in organic chemistry and much less complete. These species are highly reactive intermediates. They play a central role in the chemical vapour deposition (CVD of various silicon-containing thin films which have a technological importance in microelectronics as well as in the dry etching processes of silicon wafers. Spectroscopic methods have been developed to observe these species, a necessary pre-requisite to their direct monitoring. In this work, deuterated phenylsilane precursor, PhSiD3 was chosen for SiD2 because its analogue phenylsilane, PhSiH3 proved to be a good precursor for SiH2 and the high quality decay signals observed revealed that SiD2 be readily detected from PhSiD3 and that if other decomposition pathways (e.g. PhSiD + D2 are occurring, they do not effect measurements of the rate constants for SiD2. The absorption spectrum of SiD2 formed from the flash photolysis of a mixture of PhSiD3 and SF6 at 193nm were found in the region 17384-17391 cm-1 with strong band at 17387.07 cm-1. This single rotational line of pQ1 was chosen to monitor SiD2 removal. Time-resolved studies of SiD2 have been carried out to obtain rate constants for its bimolecular reactions with D2. The reactions were studied over the pressure range 5-100 Torr (in SF6 bath gas at four temperatures in the range 298-498K. Single decay from 10 photolysis laser shots were averaged and found to give reasonable first-order kinetics fits. Second order kinetics were obtained by pressure dependence of the pseudo first order decay constants and substance D2 pressures within experimental error. The reaction was found to be weakly pressure dependent at all temperatures, consistent with a third-body mediated association process. In addition, SiH2+ H2 reaction is approximately ca. 60% faster than SiD2+D2 reaction. Theoretical extrapolations (using

  14. Studies of atomic properties of francium and rubidium (United States)

    Perez Galvan, Adrian

    High precision measurements of atomic properties are excellent probes for electroweak interaction studies at the lowest possible energy range. The extraction of standard model coupling constants relies on a unique combination of experimental measurements and theoretical atomic structure calculations. It is only through stringent comparison between experimental and theoretical values of atomic properties that a successful experiment can take place. Francium, with its heavy nucleus and alkali structure that makes it amenable to laser cooling and trapping, stands as an ideal test bed for such studies. Our group has successfully created, trapped and cooled several isotopes of francium, the heaviest of the alkalies, and demonstrated that precision studies of atomic properties, such as the measurement of the 8S 1/2 excited state lifetime of 210Fr presented here, are feasible. Further work in our program of electroweak studies requires a better control of the electromagnetic environment observed by the sample of cold atoms as well as a lower background pressure (10-10 torr or better). We have designed and adapted to our previous setup a new "science" vacuum chamber that fulfills these requirements and the transport system that will transfer the francium atoms to the new chamber. We use this new experimental setup as well as a rubidium glass cell to perform precision studies of atomic and nuclear properties of rubidium. Spectroscopic studies of the most abundant isotopes of rubidium, 85Rb and 87Rb, are a vital component in our program. Performing measurements in rubidium allows us to do extensive and rigorous searches of systematics that can be later extrapolated to francium. We present a precision lifetime measurement of the 5D 3/2 state of 87Rb and a measurement of hyperfine splittings of the 6S1/2 level of 87Rb and 85Rb. The quality of the data of the latter allows us to observe a hyperfine anomaly attributed to an isotopic difference of the magnetization distribution

  15. Recent results of the pulsed optically pumped rubidium clock (United States)

    Levi, F.; Micalizio, S.; Godone, A.; Calosso, C.; Bertacco, E.


    A laboratory prototype of a pulsed optically pumped (POP) clock based on a rubidium cell with buffer gas is described. This clock has shown very interesting physical and metrological features, such as negligible light-shift, strongly reduced cavity-pulling and very good frequency stability. In this regard, an Allan deviation of σy(τ) = 1.2 τ-1/2 for measurement times up to τ = 105 s has been measured. These results confirm the interesting perspectives of such a frequency standard and make it very attractive for several technological applications, such as radionavigation.

  16. Two-photon excitation of rubidium atoms inside porous glass (United States)

    Amy, L.; Lenci, L.; Villalba, S.; Failache, H.; Lezama, A.


    We study the two-photon laser excitation to the 5 D5 /2 energy level of 85Rb atoms contained in the interstices of a porous material made from sintered ground glass with typical pore dimensions in the 10-100 μ m range. The excitation spectra show unusual flat-top line shapes, which are shown to be the consequence of wave-vector randomization of the laser light in the porous material. For large atomic densities, the spectra are affected by radiation trapping around the D2 transitions. The effect of the transient atomic response limited by the time of flight between pores walls appears to have a minor influence in the excitation spectra. It is however revealed by the shortening of the temporal evolution of the emitted blue light following a sudden switch-off of the laser excitation.

  17. Vanadium, rubidium and potassium in Octopus vulgaris (Mollusca: Cephalopoda

    Directory of Open Access Journals (Sweden)

    Sónia Seixas


    Full Text Available The levels of vanadium, rubidium and potassium were determined in Octopus vulgaris caught during commercial fishing activities at three locations (Cascais, Santa Luzia and Viana do Castelo in Portugal in autumn and spring. We determined the concentration of these elements in digestive gland, branchial heart, gills, mantle and arms in males and females. At least five males and five females were assessed for each season/location combination. Elemental concentrations were determined by Particle Induced X-ray Emission (PIXE. Vanadium was detectable only in digestive gland and branchial heart samples. Its concentration was not correlated with total weight, total length or mantle length. There were no differences in concentrations of V, Rb and K between sexes. There were significant differences in vanadium concentrations in branchial hearts in autumn between samples from Viana do Castelo and those from the other two sites. We found a significant positive relationship between the concentration of vanadium and those of potassium and rubidium in branchial hearts. Branchial hearts appear to play an important role in decontamination of V.

  18. Sympathetic cooling in a rubidium cesium mixture: Production of ultracold cesium atoms; Sympathetisches Kuehlen in einer Rubidium-Caesium-Mischung: Erzeugung ultrakalter Caesiumatome

    Energy Technology Data Exchange (ETDEWEB)

    Haas, M.


    This thesis presents experiments for the production of ultracold rubidium cesium mixture in a magnetic trap. The long-termed aim of the experiment is the study of the interaction of few cesium atoms with a Bose-Einstein condensate of rubidium atoms. Especially by controlled variation of the cesium atom number the transition in the description of the interaction by concepts of the one-particle physics to the description by concepts of the many-particle physics shall be studied. The rubidium atoms are trapped in a magneto-optical trap (MOT) and from there reloaded into a magnetic trap. In this the rubidium atoms are stored in the state vertical stroke f=2,m{sub f}=2 right angle of the electronic ground state and evaporatively cooled by means of microwave-induced transitions into the state vertical stroke f=1,m{sub f}=1] (microwave cooling). The cesium atoms are also trppaed in a MOT and into the same magnetic trap reloaded, in which they are stored in the state vertical stroke f=4,m{sub f}=4 right angle of the electronic ground state together with rubidium. Because of the different hyperfine splitting only rubidium is evaporatively cooled, while cesium is cooled jointly sympathetically - i.e. by theramal contact via elastic collisions with rubidium atoms. The first two chapters contain a description of interatomic interactions in ultracold gases as well as a short summary of theoretical concepts in the description of Bose-Einstein condensates. The chapters 3 and 4 contain a short presentation of the methods applied in the experiment for the production of ultracold gases as well as the experimental arrangement; especially in the framework of this thesis a new coil system has been designed, which offers in view of future experiments additionally optical access for an optical trap. Additionally the fourth chapter contains an extensive description of the experimental cycle, which is applied in order to store rubidium and cesium atoms together into the magnetic trap. The

  19. A laser system for the spectroscopy on highly charged ions, tellurium molecules, and Rydberg states of rubidium atoms; Ein Lasersystem zur Spektroskopie von hochgeladenen Ionen, Tellurmolekuelen und Rubidium-Rydberg-Zustaenden

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, Sebastian


    Optical measuring methods allow the detection and identification of the atomic structure with extraordinary precision. Deviations to theoretical predictions can indicate unknown physical effects. Therefore, precise measurements on the atomic structure continue to be of large relevance. In this work, a laser system for precision spectroscopy on Bismuth ({sup 209}Bi{sup 82+}), Tellurium ({sup 130}Te{sub 2}) and Rydberg states of Rubidium ({sup 85}Rb) has been built and characterized. Spectroscopic measurements on Tellurium and Rubidium have been achieved with this setup. The system consists of a two-stage frequency doubled diode laser, stabilized via a cavity and an RF-offsetlock to arbitrary wavelengths with absolute high stability. The setup of the laser system will be presented and the systematic error caused by the refractive index of air inside the transfer cavity will be discussed. A stability of better then 6.14 MHz at 244 nm is obtained for planned experiments on the ground state hyperfine splitting of {sup 209}Bi{sup 82+}. This will allow an increase in precision of more then four orders of magnitude for this measurement. Further increase in precision can be achieved by using an evacuated cavity. The obtained stability is measured by comparison of the laser frequency to absorption lines of Tellurium ({sup 130}Te{sub 2}). Eight reference lines, known from literature, spanning the region from 613720.717 GHz to 616803.545 GHz have been measured. The frequency measurements of three lines, coinciding with the emission spectrum of an argon-ion-laser, show deviations with respect to the published frequencies. Further inconsistencies in literature are cleared. Part of this work is also the precise measurement of 843 Doppler-free {sup 130}Te{sub 2} reference lines spanning the frequency range from 613881.150 GHz to 616614.258 GHz at a precision of better then 4 MHz for most lines. Additionally, measurements on electromagnetically induced transparency (EIT) using

  20. LINES

    Directory of Open Access Journals (Sweden)

    Minas Bakalchev


    Full Text Available The perception of elements in a system often creates their interdependence, interconditionality, and suppression. The lines from a basic geometrical element have become the model of a reductive world based on isolation according to certain criteria such as function, structure, and social organization. Their traces are experienced in the contemporary world as fragments or ruins of a system of domination of an assumed hierarchical unity. How can one release oneself from such dependence or determinism? How can the lines become less “systematic” and forms more autonomous, and less reductive? How is a form released from modernistic determinism on the new controversial ground? How can these elements or forms of representation become forms of action in the present complex world? In this paper, the meaning of lines through the ideas of Le Corbusier, Leonidov, Picasso, and Hitchcock is presented. Spatial research was made through a series of examples arising from the projects of the architectural studio “Residential Transformations”, which was a backbone for mapping the possibilities ranging from playfulness to exactness, as tactics of transformation in the different contexts of the contemporary world.

  1. D2 Inertial Measurement Unit (United States)

    Dewar, Patrick; Gido, Joseph; Carroll, Joseph


    The D2 Hypervelocity Projectile is a Strategic Defense Initiative sponsored technology program that is designed to provide low endo-atmospheric, kinetic kill defense against strategic reentry vehicles. The D2 program is funded through the U.S. Army Space and Strategic Defense Command (SSDC) in Huntsville, AL and contracted through the U.S. Army Armament Research and Development Engineering Center (ARDEC) at Picatinny Arsenal, NJ. In GFY 93 the program began an integration and flight demonstration phase with the Hypervelocity Fire Control System (HVFC) and the Solid Propellant Electro Thermal Chemical (SPETC) launcher. The Inertial Measurement Unit (IMU) necessary to perform the autopilot and guidance data gathering must be extremely small, lightweight and shock hardened. The IMU is comprised of three Honeywell GG1308 miniature Ring Laser Gyros (RLG), and three Endevco 7290-M19 miniature silicon accelerometers. The IMU has self-contained high voltage Power Supply (HVPS) processor and memory electronics providing a complete stand alone, three axis measurement package. This Inertial Cluster Assembly (ICA) is then packaged into a cylindrical housing, approximately 1.9 inches in diameter and 1.3 inches in length.

  2. The Road to DLCZ Protocol in Rubidium Ensemble (United States)

    Li, Chang; Pu, Yunfei; Jiang, Nan; Chang, Wei; Zhang, Sheng; Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua Univ Team


    Quantum communication is the powerful approach achieving a fully secure information transferal. The DLCZ protocol ensures that photon linearly decays with transferring distance increasing, which improves the success potential and shortens the time to build up an entangled channel. Apart from that, it provides an advanced idea that building up a quantum internet based on different nodes connected to different sites and themselves. In our laboratory, three sets of laser-cooled Rubidium 87 ensemble have been built. Two of them serve as the single photon emitter, which generate the entanglement between ensemble and photon. What's more, crossed AODs are equipped to multiplex and demultiplex optical circuit so that ensemble is divided into 2 hundred of 2D sub-memory cells. And the third ensemble is used as quantum telecommunication, which converts 780nm photon into telecom-wavelength one. And we have been building double-MOT system, which provides more atoms in ensemble and larger optical density.

  3. Pre-Excitation Studies for Rubidium-Plasma Generation

    CERN Document Server

    Aladi, M; Barna, I.F.; Czitrovszky, Aladar; Djotyan, Gagik; Dombi, Peter; Dzsotjan, David; FöLdes, Istvan; Hamar, Gergo; Ignacz, Peter; Kedves, Miklos; Kerekes, Attila; Levai, Peter; Marton, Istvan; Nagy, Attila; Oszetzky, Daniel; Pocsai, Mihaly; Racz, Peter; Raczkevi, Bela; Szigeti, Janos; Sörlei, Zsuzsa; Szipöcs, Robert; Varga, Dezso; Varga-Umbrich, Karoly; Varro, Sandor; Vamos, Lenard; Vesztergombi, György


    The key element in the Proton-Driven-Plasma-Wake-Field-Accelerator (AWAKE) project is the generation of highly uniform plasma from Rubidium vapor. The standard way to achieve full ionization is to use high power laser which can assure the over-barrier-ionization (OBI) along the 10 meters long active region. The Wigner-team in Budapest is investigating an alternative way of uniform plasma generation. The proposed Resonance Enhanced Multi Photon Ionization (REMPI) scheme probably can be realized by much less laser power. In the following the resonant pre-excitations of the Rb atoms are investigated, theoretically and the status report about the preparatory work on the experiment are presented.

  4. Synthesis, Spectroscopic, and Magnetic Properties of Rubidium Heptachlorodiuranate(III) (United States)

    Karbowiak, Mirosław; Hanuza, Jerzy; Drożdżyński, Janusz; Hermanowicz, Krzysztof


    The synthesis of rubidium heptachlorodiuranate(III) together with some of its structural, spectroscopic, and magnetic properties are reported. Unit cell parameters were determined from X-ray powder diffraction data. Uranium(3+) doped single crystals of RbY2Cl7have been grown by the Bridgman-Stockbarger method. The Raman and infrared spectra of RbU2Cl7as well as the electronic absorption spectrum of RbY2Cl7: U3+(1%) at 4.2 K have been recorded and are discussed. Magnetic susceptibility measurements were carried out by the Faraday method in the 4.2-300 K range. The Curie-Weiss law is followed in the 210-300 K range with the paramagnetic constants μeff= 3.74 μB,C= 1.750 emu·K·mole-1, and θ = -80 K.

  5. The positrons emission tomography in cardiology on expecting for the rubidium 82; La tomographie par emission de positons en cardiologie en attendant le rubidium-82

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, D. [Societe Francaise de Cardiologie Nucleaire et IRM, 75 - Paris (France)


    The positron emission tomography in cardiology has an important place in France. A new tracer, the rubidium 82 can be used for the detection of myocardium ischemia among the patients where the SPECT was ineffective or not very useful, it will be necessary to propose a permit to market the tracer in the two next years.Recently, the Food drug administration in Usa has allowed the repayment of the rubidium 82 for the myocardium detection as normal or abnormal in the post myocardium infarction. (N.C.)

  6. Data on inelastic processes in low-energy potassium-hydrogen and rubidium-hydrogen collisions (United States)

    Yakovleva, S. A.; Barklem, P. S.; Belyaev, A. K.


    Two sets of rate coefficients for low-energy inelastic potassium-hydrogen and rubidium-hydrogen collisions were computed for each collisional system based on two model electronic structure calculations, performed by the quantum asymptotic semi-empirical and the quantum asymptotic linear combinations of atomic orbitals (LCAO) approaches, followed by quantum multichannel calculations for the non-adiabatic nuclear dynamics. The rate coefficients for the charge transfer (mutual neutralization, ion-pair formation), excitation and de-excitation processes are calculated for all transitions between the five lowest lying covalent states and the ionic states for each collisional system for the temperature range 1000-10 000 K. The processes involving higher lying states have extremely low rate coefficients and, hence, are neglected. The two model calculations both single out the same partial processes as having large and moderate rate coefficients. The largest rate coefficients correspond to the mutual neutralization processes into the K(5s 2S) and Rb(4d 2D) final states and at temperature 6000 K have values exceeding 3 × 10-8 cm3 s-1 and 4 × 10-8 cm3 s-1, respectively. It is shown that both the semi-empirical and the LCAO approaches perform equally well on average and that both sets of atomic data have roughly the same accuracy. The processes with large and moderate rate coefficients are likely to be important for non-LTE modelling in atmospheres of F, G and K-stars, especially metal-poor stars.

  7. 7 CFR 15d.2 - Discrimination prohibited. (United States)


    ..., religion, sex, age, national origin, marital status, familial status, sexual orientation, or disability, or... 7 Agriculture 1 2010-01-01 2010-01-01 false Discrimination prohibited. 15d.2 Section 15d.2... THE UNITED STATES DEPARTMENT OF AGRICULTURE § 15d.2 Discrimination prohibited. (a) No agency, officer...

  8. Distribution of rubidium between sodic sanidine and natural silicic liquid (United States)

    Noble, D.C.; Hedge, C.E.


    Phenocrysts of sodic sanidine from twelve upper Cenozoic units of silicic ash-flow tuff and lava from the Western United States contain from 0.25 to 0.45 the Rb present in the associated groundmass materials. The ratios of potassium to rubidium in the sanidines are, on the average, about four times greater than those of the groundmass. Separation of phenocrystic sanidine from salic melts provides an efficient method for raising the Rb content and lowering the K/Rb ratio of the melts, although the amount of differentiation probably is limited by continuous reequilibration of the alkalis between crystal and liquid phases through ion exchange. Syenites of cumulate origin will have appreciably lower Rb contents and higher K/Rb ratios than the melts from which they precipitated. Available data on the distribution of Rb between synthetic biotite and K-sanidine demonstrate that the separation of biotite probably will not deplete salic melts in Rb relative to K. ?? 1970 Springer-Verlag.

  9. Detection of Interstellar Ortho-D2H+ with SOFIA (United States)

    Harju, Jorma; Sipilä, Olli; Brünken, Sandra; Schlemmer, Stephan; Caselli, Paola; Juvela, Mika; Menten, Karl M.; Stutzki, Jürgen; Asvany, Oskar; Kamiński, Tomasz; Okada, Yoko; Higgins, Ronan


    We report on the detection of the ground-state rotational line of ortho-D2H+ at 1.477 THz (203 μm) using the German REceiver for Astronomy at Terahertz frequencies (GREAT) on board the Stratospheric Observatory For Infrared Astronomy (SOFIA). The line is seen in absorption against far-infrared continuum from the protostellar binary IRAS 16293-2422 in Ophiuchus. The para-D2H+ line at 691.7 GHz was not detected with the APEX telescope toward this position. These D2H+ observations complement our previous detections of para-H2D+ and ortho-H2D+ using SOFIA and APEX. By modeling chemistry and radiative transfer in the dense core surrounding the protostars, we find that the ortho-D2H+ and para-H2D+ absorption features mainly originate in the cool (T emission from the core is significantly absorbed by the ambient molecular cloud. Analyses of the combined D2H+ and H2D+ data result in an age estimate of ˜5 × 105 yr for the core, with an uncertainty of ˜2 × 105 yr. The core material has probably been pre-processed for another 5 × 105 years in conditions corresponding to those in the ambient molecular cloud. The inferred timescale is more than 10 times the age of the embedded protobinary. The D2H+ and H2D+ ions have large and nearly equal total (ortho+para) fractional abundances of ˜10-9 in the outer envelope. This confirms the central role of {{{H}}}3+ in the deuterium chemistry in cool, dense gas, and adds support to the prediction of chemistry models that also {{{D}}}3+ should be abundant in these conditions.

  10. A Circuit to Improve Power Amplitude Stability in Miniature Rubidium Atomic Frequency Standard

    Directory of Open Access Journals (Sweden)

    LUO Qi


    Full Text Available The radiofrequency circuit of traditional miniature rubidium atomic frequency standard (RAFS uses saturated output, which can stabilize the amplitude, but not the waveform, of the radiofrequency signal. This would lead to insufficient microwave power stability. In this study, an improved circuit for stabilizing power amplitude in miniature rubidium atomic frequency standard was described. The circuit took the bias voltage of step recovery diode (SRD as a reference to achieve automatic gain control (AGC through controlling the gain of the variable gain amplifier (VGA. This scheme controlled both the amplitude and the waveform of the radiofrequency signal. The results showed that this scheme can effectively improve power stability of the microwave signal in miniature rubidium atomic frequency standard.

  11. arXiv Interferometer-based high-accuracy white light measurement of neutral rubidium density and gradient at AWAKE

    CERN Document Server

    Batsch, Fabian; Oez, Erdem; Moody, Joshua; Gschwendtner, Edda; Caldwell, Allen; Muggli, Patric

    The AWAKE experiment requires an automated online rubidium (Rb) plasma density and gradient diagnostic for densities between 1 and 10$\\cdot$10$^{14}$ cm$^{-3}$. A linear density gradient along the plasma source at the percent level may be useful to improve the electron acceleration process. Because of full laser ionization of Rb vapor to Rb$^{+}$ within a radius of 1 mm, the plasma density equals the vapor density. We measure the Rb vapor densities at both ends of the source, with high precision using, white light interferometry. At either source end, broadband laser light passes a remotely controlled Mach-Zehnder interferometer built out of single mode fibers. The resulting interference signal, influenced by dispersion in the vicinity of the Rb D1 and D2 transitions, is dispersed in wavelength by a spectrograph. Fully automated Fourier-based signal conditioning and a fit algorithm yield the density with an uncertainty between the measurements at both ends of 0.11 to 0.46 $\\%$ over the entire density range. T...

  12. Structural, thermal and electrical studies of a novel rubidium phosphite tellurate compound

    DEFF Research Database (Denmark)

    Beyribey, Didem Berceste; Hallinder, Jonathan


    Structural, thermal and electrical properties studies of rubidium phosphite tellurate, RbH(PO3H)·Te(OH)6, were performed. An endothermic peak, which reached a completion at about 315 °C accompanied with a weight loss of 4.6 wt.%, was attributed to dehydration. Four types of pellets were produced...

  13. 86Rubidium uptake in mononuclear leucocytes from young subjects at increased risk of developing essential hypertension

    DEFF Research Database (Denmark)

    Nielsen, J R; Johansen, Torben; Pedersen, K E


    parents. 86Rubidium uptake was significantly increased in the borderline hypertensive subjects, especially in the borderline hypertensive offspring of hypertensive patients. Our results indicate that the sodium-potassium pump is activated in mononuclear leucocytes from borderline hypertensives......, and especially in those borderline hypertensives with at least one hypertensive parent. The latter group was also the group at greatest risk of developing essential hypertension....

  14. Rubidium atomic beam clock based on lamp-pumping and fluorescence-detection scheme (United States)

    Wang, Y. H.; Huang, J. Q.; Gu, Y.; Liu, S. Q.; Dong, T. Q.; Lu, Z. H.


    A compact, portable rubidium atomic beam clock based on lamp-pumping and fluorescence-detection scheme is proposed. The expected short-term frequency stability can be at least two orders of magnitude better than previous experimental results. The usages of lamp pumping, fluorescence detection and microwave slow-wave resonance structures make this design robust and compact.

  15. Seasonal Variation of Provitamin D2 and Vitamin D2 in Perennial Ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Jäpelt, Rie Bak; Didion, Thomas; Smedsgaard, Jørn


    Ergosterol (provitamin D(2)) is converted to vitamin D(2) in grass by exposure to UV light. Six varieties of perennial ryegrass (Lolium perenne L.) were harvested four times during the season, and the contents of vitamin D(2) and ergosterol were analyzed by a sensitive and selective liquid...

  16. Ligand-Induced Regulation and Localization of Cannabinoid CB1 and Dopamine D2L Receptor HeterodimersS⃞


    Przybyla, Julie A.; Val J Watts


    The cannabinoid CB1 (CB1) and dopamine D2 (D2) receptors are coexpressed in the basal ganglia, an area of the brain involved in such processes as cognition, motor function, and emotional control. Several lines of evidence suggest that CB1 and D2 receptors may oligomerize, providing a unique pharmacology in vitro and in vivo. However, limited information exists on the regulation of CB1 and D2 receptor ...

  17. Evidence for genetic heterogeneity in D-2-hydroxyglutaric aciduria

    DEFF Research Database (Denmark)

    Kranendijk, Martijn; Struys, Eduard A; Gibson, K Michael


    We performed molecular, enzyme, and metabolic studies in 50 patients with D-2-hydroxyglutaric aciduria (D-2-HGA) who accumulated D-2-hydroxyglutarate (D-2-HG) in physiological fluids. Presumed pathogenic mutations were detected in 24 of 50 patients in the D-2-hydroxyglutarate dehydrogenase (D2HGD...

  18. Direct observation of an isomeric state in {sup 98}Rb and nuclear properties of exotic rubidium isotopes measured by laser spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Procter, T.J.; Garnsworthy, A.B.; Levy, C.D.P.; Pearson, M.R. [TRIUMF, Vancouver, British Columbia (Canada); Behr, J.A.; Dilling, J. [TRIUMF, Vancouver, British Columbia (Canada); University of British Columbia, Department of Physics, Vancouver, British Columbia (Canada); Billowes, J. [The University of Manchester, School of Physics and Astronomy, Manchester (United Kingdom); Buchinger, F.; Crawford, J.E.; Leary, A.; Shelbaya, O.; Al Tamimi, W. [McGill University, Physics Department, Montreal, Quebec (Canada); Cheal, B. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Mane, E. [TRIUMF, Vancouver, British Columbia (Canada); Ministry of External Relations, Rio Bianco Institute, Brasilia (Brazil); Stolz, M. [Technische Universitaet Berlin, Berlin (Germany); Voss, A. [TRIUMF, Vancouver, British Columbia (Canada); University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland)


    Fast-beam collinear laser spectroscopy experiments on rubidium have been performed at the ISAC radioactive ion beam facility at TRIUMF. Most recently, the neutron-rich {sup 98}Rb isotope has been studied for the investigation of shape coexistence. Two long-lived nuclear states in {sup 98}Rb have been clearly observed for the first time: a low-spin state, assigned a spin of I = 0, and a high-spin state. The high-spin state is tentatively assigned a spin of I = 3 based on this analysis in combination with gamma decay results. The measured nuclear properties of the two states are presented, alongside unpublished values of the neutron-deficient isotopes investigated previously. The mean-square charge radii of both states in {sup 98}Rb are observed to continue along the isodeformation line present after the N = 60 onset of deformation. (orig.)

  19. Evidence for genetic heterogeneity in D-2-hydroxyglutaric aciduria

    DEFF Research Database (Denmark)

    Kranendijk, Martijn; Struys, Eduard A; Gibson, K Michael


    We performed molecular, enzyme, and metabolic studies in 50 patients with D-2-hydroxyglutaric aciduria (D-2-HGA) who accumulated D-2-hydroxyglutarate (D-2-HG) in physiological fluids. Presumed pathogenic mutations were detected in 24 of 50 patients in the D-2-hydroxyglutarate dehydrogenase (D2HGDH......) gene, which encodes D-2-hydroxyglutarate dehydrogenase (D-2-HGDH). Enzyme assay of D-2-HGDH confirmed that all patients with mutations had impaired enzyme activity, whereas patients with D-2-HGA whose enzyme activity was normal did not have mutations. Significantly lower D-2-HG concentrations in body...... fluids were observed in mutation-positive D-2-HGA patients than in mutation-negative patients. These results imply that multiple genetic loci may be associated with hyperexcretion of D-2-HG. Accordingly, we suggest a new classification: D-2-HGA Type I associates with D-2-HGDH deficiency, whereas...

  20. Autonomous Rubidium Clock Weak Frequency Jump Detector for Onboard Navigation Satellite System. (United States)

    Khare, Akshay; Arora, Rajat; Banik, Alak; Mehta, Sanjay D


    Frequency jumps are common in rubidium frequency sources. They affect the estimation of user position in navigational satellite systems. These jumps must be detected and corrected immediately as they have direct impact on the navigation system integrity. A novel weak frequency jump detector is proposed based on a Kalman filter with a multi-interval approach. This detector can be applied for both "sudden" and "slow" frequency transitions. In this detection method, noises of clock data are reduced by Kalman filtering, for accurate estimation of jump size with less latency. Analysis on in-orbit rubidium atomic frequency standard (RAFS) phase telemetry data shows that the detector can be used for fast detection and correction of weak frequency jumps. Furthermore, performance comparison of different existing frequency jump detection techniques with the proposed detector is discussed. A multialgorithm-based strategy is proposed depending on the jump size and latency for onboard navigation satellites having RAFS as the primary frequency source.

  1. Absorption Spectroscopy of Rubidium in an Alkali Metal Dispenser Cell and Bleached Wave Analysis (United States)


    7 wavemeter. The beam propagated through a 5 cm Rb cell with Ne buffer gas and onto a beam stop, and the Marlin camera captured images of the side...and directed through the rubidium cell. A Marlin IEEE 1394 camera (and at later points in the study a Manta G-609 camera) was placed perpendicular...with a commercial color camera, not the mounted Marlin camera used for indentifying the intensity indices at each point in the cell). The region

  2. Early risk stratification using Rubidium-82 positron emission tomography in STEMI patients

    DEFF Research Database (Denmark)

    Ghotbi, Adam Ali; Hasbak, Philip; Nepper-Christensen, Lars


    BACKGROUND: Assessment of infarct size after myocardial infarction is predictive of subsequent morphological changes and clinical outcome. This study aimed to assess subacute post-intervention Rubidium-82 ((82)Rb)-PET imaging in predicting left ventricle ejection fraction, regional wall motion....... CONCLUSIONS: Subacute rest-only (82)Rb-PET is feasible following STEMI and seems predictive of myocardial function and infarct size at 3-months....

  3. Measurement of the Temperature of Rubidium Atoms in a Magneto-Optical Trap

    Directory of Open Access Journals (Sweden)

    J. W. F. Liwag


    Full Text Available We have performed measurements that can be used to determine the temperature of rubidium atoms in a magneto-optical trap.The expansion of the atomic cloud after switching off the current through the anti-Helmholtz coils was recorded with a CCDcamera. Analysis of the measurements revealed that the cloud of atoms in optical molasses expands at a velocity of 4 cm/s.

  4. Antimicrobial susceptibility of Corynebacterium group D2. (United States)

    Santamaría, M; Ponte, C; Wilhelmi, I; Soriano, F


    The in vitro susceptibility of 30 Corynebacterium group D2 strains to nine antimicrobial agents was determined. Vancomycin and norfloxacin were the most active agents tested. All strains were resistant to ampicillin and cephalothin, all except one were resistant to gentamicin, and the activity of erythromycin, novobiocin, tetracycline, and rifampin varied. PMID:4083869

  5. Cocaine Inhibits Dopamine D2 Receptor Signaling via Sigma-1-D2 Receptor Heteromers (United States)

    Navarro, Gemma; Moreno, Estefania; Bonaventura, Jordi; Brugarolas, Marc; Farré, Daniel; Aguinaga, David; Mallol, Josefa; Cortés, Antoni; Casadó, Vicent; Lluís, Carmen; Ferre, Sergi


    Under normal conditions the brain maintains a delicate balance between inputs of reward seeking controlled by neurons containing the D1-like family of dopamine receptors and inputs of aversion coming from neurons containing the D2-like family of dopamine receptors. Cocaine is able to subvert these balanced inputs by altering the cell signaling of these two pathways such that D1 reward seeking pathway dominates. Here, we provide an explanation at the cellular and biochemical level how cocaine may achieve this. Exploring the effect of cocaine on dopamine D2 receptors function, we present evidence of σ1 receptor molecular and functional interaction with dopamine D2 receptors. Using biophysical, biochemical, and cell biology approaches, we discovered that D2 receptors (the long isoform of the D2 receptor) can complex with σ1 receptors, a result that is specific to D2 receptors, as D3 and D4 receptors did not form heteromers. We demonstrate that the σ1-D2 receptor heteromers consist of higher order oligomers, are found in mouse striatum and that cocaine, by binding to σ1 -D2 receptor heteromers, inhibits downstream signaling in both cultured cells and in mouse striatum. In contrast, in striatum from σ1 knockout animals these complexes are not found and this inhibition is not seen. Taken together, these data illuminate the mechanism by which the initial exposure to cocaine can inhibit signaling via D2 receptor containing neurons, destabilizing the delicate signaling balance influencing drug seeking that emanates from the D1 and D2 receptor containing neurons in the brain. PMID:23637801

  6. Neptune's small dark spot (D2) (United States)


    This bulls-eye view of Neptune's small dark spot (D2) was obtained by Voyager 2's narrow-angle camera. Banding surrounding the feature indicates unseen strong winds, while structures within the bright spot suggest both active upwelling of clouds and rotation about the center. A rotation rate has not yet been measured, but the V-shaped structure near the right edge of the bright area indicates that the spot rotates clockwise. Unlike the Great Red Spot on Jupiter, which rotates counterclockwise, if the D2 spot on Neptune rotates clockwise, the material will be descending in the dark oval region. The fact that infrared data will yield temperature information about the region above the clouds makes this observation especially valuable. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.

  7. Rubidium-rich feldspars and associated minerals from the Luolamäki pegmatite, Somero, Finland

    Directory of Open Access Journals (Sweden)

    Teerstra, D.K.


    Full Text Available Rubidium feldspar occurs near the core zone of the highly fractionated petalite-subtype Luolamäki granitic pegmatite in intimate intergrowth with other feldspars which are part of a characteristic sequence of alteration of pollucite. Pods of pollucite are cut by 5-20 cm-wide veins of albite, petalite, non-perthitic microcline, lepidolite and quartz, by thinner veins of fine-grained micas and spodumene, and are replaced by metasomatic adularia. Grains of rubidium feldspar occur as a potentially ordered phase in the vein microcline in association with earlier-exsolved albite, and also as late thin (< 5 μm veinlets. Rubidium feldspar also occurs as a potentially disordered phase which crystallized along with metasomatic adularia. Both generations of (Rb,K-feldspar have a similar compositional range, close to the join KAlSi3O8-RbAlSi3O8, typically with up to ~21 wt.% Rb2O (~70 mol.% Rbf and with minor Cs, but neglible Na, Ca, Fe or P. Extreme compositions have 26.0 wt.% Rb2O (89.0 mol.% Rbf and 1.26 wt.% Cs2O (2.8 mol.% Csf. The diffuse compositional gradients from microcline to rubicline are consistent with a solid-state exsolution origin, followed by fluid-assisted textural coarsening which generates distinct phase boundaries. In contrast, metasomatic adularian (Rb,K-feldspar was precipitated at low temperature (250-150°C and fine-scale zoning with variable K/Rb is preserved as a growth feature.

  8. Degenerate mixtures of rubidium and ytterbium for engineering open quantum systems (United States)

    Vaidya, Varun Dilip

    In the last two decades, experimental progress in controlling cold atoms and ions now allows us to manipulate fragile quantum systems with an unprecedented degree of precision. This has been made possible by the ability to isolate small ensembles of atoms and ions from noisy environments, creating truly closed quantum systems which decouple from dissipative channels. However in recent years, several proposals have considered the possibility of harnessing dissipation in open systems, not only to cool degenerate gases to currently unattainable temperatures, but also to engineer a variety of interesting many-body states. This thesis will describe progress made towards building a degenerate gas apparatus that will soon be capable of realizing these proposals. An ultracold gas of ytterbium atoms, trapped by a species-selective lattice will be immersed into a Bose-Einstein condensate (BEC) of rubidium atoms which will act as a bath. Here we describe the challenges encountered in making a degenerate mixture of rubidium and ytterbium atoms and present two experiments performed on the path to creating a controllable open quantum system. The first experiment will describe the measurement of a tune-out wavelength where the light shift of 87Rb vanishes. This wavelength was used to create a species-selective trap for ytterbium atoms. Furthermore, the measurement of this wavelength allowed us to extract the dipole matrix element of the 5s → 6p transition in 87Rb with an extraordinary degree of precision. Our method to extract matrix elements has found use in atomic clocks where precise knowledge of transition strengths is necessary to account for minute blackbody radiation shifts. The second experiment will present the first realization of a degenerate Bose-Fermi mixture of rubidium and ytterbium atoms. Using a three-color optical dipole trap (ODT), we were able to create a highly-tunable, species-selective potential for rubidium and ytterbium atoms which allowed us to use 87

  9. Quantum interference spectroscopy of rubidium-helium exciplexes formed on helium nanodroplets. (United States)

    Mudrich, M; Stienkemeier, F; Droppelmann, G; Claas, P; Schulz, C P


    Femtosecond multiphoton pump-probe photoionization is applied to helium nanodroplets doped with rubidium (Rb). The yield of Rb+ ions features pronounced quantum interference (QI) fringes demonstrating the coherence of a superposition of electronic states on a time scale of tens of picoseconds. Furthermore, we observe QI in the yield of formed RbHe exciplex molecules. The quantum interferogram allows us to determine the vibrational structure of these unstable molecules. From a sliced Fourier analysis one cannot only extract the population dynamics of vibrational states but also follow their energetic evolution during the RbHe formation.

  10. A stable frequency comb directly referenced to rubidium electromagnetically induced transparency and two-photon transitions

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Dong; Wu, Jiutao; Zhang, Shuangyou; Ren, Quansheng; Zhang, Zhigang; Zhao, Jianye, E-mail: [Department of Electronics, Peking University, Beijing, 100871 (China)


    We demonstrate an approach to create a stable erbium-fiber-based frequency comb at communication band by directly locking the combs to two rubidium atomic transitions resonances (electromagnetically induced transparency absorption and two-photon absorption), respectively. This approach directly transfers the precision and stability of the atomic transitions to the comb. With its distinguishing feature of compactness by removing the conventional octave-spanning spectrum and f-to-2f beating facilities and the ability to directly control the comb's frequency at the atomic transition frequency, this stable optical comb can be widely used in optical communication, frequency standard, and optical spectroscopy and microscopy.

  11. Energy Pooling, Ion Recombination, and Reactions of Rubidium and Cesium in Hydrocarbon Gasses. (United States)

    Bresler, Sean Michael; Park, J.; Heaven, Michael


    Diode Pumped Alkali Lasers (DPAL) are continuous wave lasers, potentially capable of megawatt average powers. These lasers exploit the D1 and D2 lines of alkali metals resulting in a 3-level laser with the lasing transition in the near infrared region of the electromagnetic spectrum. Energy pooling processes involving collisions between excited alkali metals cause a fraction of the gain media to be highly excited and eventually ionized. These high energy cesium atoms and ions chemically react with small hydrocarbons utilized as buffer gasses for the system, depleting the gain media. A kinetic model supported by experimental data is introduced to explain the cumulative effects of optical trapping, energy pooling, and chemical reactivity in heavy alkali metal (Rb, Cs) systems. Spectroscopic studies demonstrating metal hydride formation will also be presented.

  12. High-flux cold rubidium atomic beam for strongly-coupled cavity QED

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Basudev [Indian Institute of Science Education and Research, Kolkata (India); University of Maryland, MD (United States); Scholten, Michael [University of Maryland, MD (United States)


    This paper presents a setup capable of producing a high-flux continuous beam of cold rubidium atoms for cavity quantum electrodynamics experiments in the region of strong coupling. A 2D{sup +} magneto-optical trap (MOT), loaded with rubidium getters in a dry-film-coated vapor cell, fed a secondary moving-molasses MOT (MM-MOT) at a rate greater than 2 x 10{sup 10} atoms/s. The MM-MOT provided a continuous beam with a tunable velocity. This beam was then directed through the waist of a cavity with a length of 280 μm, resulting in a vacuum Rabi splitting of more than ±10 MHz. The presence of a sufficient number of atoms in the cavity mode also enabled splitting in the polarization perpendicular to the input. The cavity was in the strong coupling region, with an atom-photon dipole coupling coefficient g of 7 MHz, a cavity mode decay rate κ of 3 MHz, and a spontaneous emission decay rate γ of 6 MHz.

  13. The effect of rubidium chloride on properties of organic light-emitting diodes (United States)

    Lü, Zhaoyue; Deng, Zhenbo; Du, Hailiang; Li, Degang; Zou, Ye; Xu, Denghui; Chen, Zheng; Wang, Yongsheng


    A multilayer organic light-emitting diode (OLED) was fabricated with a thin rubidium chloride (RbCl) layer inserted inside an electron transport layer (ETL), tris (8-hydroxyquinoline) aluminum (Alq 3). Here, we set d is the distance of the RbCl layer away from the Alq 3/Al interface. The rubidium chloride layer was inserted inside 60 nm Alq 3 at d = 0.0, 2.5, 5.0, 7.5, 10, 20 and 30 nm positions. When the RbCl layer is positioned closer to the Al cathode, both the current density and EL efficiency are enhanced due to the enhanced electron injection. The devices show the electroluminescent (EL) efficiency improvement without an enhanced injection if the value of d is lager than 5.0 nm. The suggested mechanism of RbCl EL efficiency enhancer is carrier trap sites induced by the thin RbCl layer. The trapped charges alter the distribution of the field inside the OLED and, consequently, give better recombination in the device.

  14. Rubidium uptake of mononuclear leukocytes from normotensive and borderline hypertensive first degree relatives to patients with essential hypertension

    DEFF Research Database (Denmark)

    Johansen, Torben; Nielsen, J R; Poulsgård, L


    Uptake of 86Rubidium of mononuclear leukocytes (MNL) was used as a measure of cellular sodium-potassium pump activity. 86Rb-uptake was determined with the pump stimulated mainly from inside the cells by sodium as well as with a combined stimulation from inside by sodium and from outside by Rb...

  15. Photoionization Models of Bromine, Rubidium, and Xenon in Planetary Nebulae (United States)

    Sterling, Nicholas C.; Porter, Ryan; Spencer, Courteney; Sherrard, Cameroun G.


    We present numerical simulations of the Br, Rb, and Xe ionization balance in five planetary nebulae (PNe). These neutron-capture elements (atomic number Z > 30) can be enriched by s-process nucleosynthesis during the asymptotic giant branch (AGB) evolutionary stage of PN progenitor stars. Recent calculations of photoionization cross sections and rate coefficients for radiative recombination, dielectronic recombination, and charge transfer (Kerlin et al. 2017, in preparation; Sterling & Kerlin 2016, 227th AAS, #238.02; Sterling & Stancil 2011, A&A, 535, A117) allow the Br, Rb, and Xe ionization equilibria to be modeled in PNe for the first time. We have added these elements and their atomic data to Cloudy (Ferland et al. 2013, RMxA&A, 49, 137). We model the PNe IC 418, IC 2501, IC 4191, NGC 2440, and NGC 7027, all of which exhibit emission from multiple Xe ions in the optical data of Sharpee et al. (2007, ApJ, 659, 1265). Multiple Br and Rb ions were also detected in NGC 7027. The model central star temperatures and luminosities, and nebular densities, outer radii, and abundances were optimized to best reproduce the observed intensities of Sharpee et al. We find that IC 418 and NGC 7027 are enriched in Br, Rb, and Xe, in accordance with results for Se and Kr (Sterling et al. 2015, ApJS, 218, 25). Given the small sample size and the weakness of the lines involved, it is not clear whether discrepancies between modeled and observed intensities are due to observational, model, or atomic data uncertainties. This sample will be expanded to include other PNe, such as those in our optical survey (Sherrard et al. poster, this session), which will allow us to test the veracity of the new atomic data for Xe and, for a smaller number of PNe, Br and Rb. Following the methods of Sterling et al. (2015), grids of Cloudy models will be computed to derive ionization correction factors for Br, Rb, and Xe for the first time, allowing their abundances to be determined with higher

  16. Scanning Tunneling Microscopy and X-Ray Diffraction of Charge Density Wave Materials and the Rubidium Isotope Effect in Superconducting RUBIDIUM(3)CARBON(60) (United States)

    Burk, Brian D.

    We image the surfaces of K_ {0.3}MoO_3 and Rb_{0.3}MoO_3 with scanning tunneling microscopy (STM) above and below the charge density wave (CDW) transition temperature (T_ p). Surprisingly, below T_ p real space and Fourier transformed images show no evidence of CDW modulation, suggesting a relatively small CDW amplitude at the sample surface. Furthermore, the lattice images that we obtained below T_ p are unaffected by the sliding of the CDW. With STM and x-ray diffraction we investigate the CDW domain structure of 1T-TaS_2 in the nearly commensurate (NC), triclinic (T), and incommensurate (I) phases. Fourier transformed STM images of the NC phase show fine satellite structure surrounding CDW peaks. The satellite structure confirms that the apparent domain-like modulation seen in real space images results from a true domain structure rather than from a moire pattern. STM images of the T phase indicate a surface striped domain pattern that is contrary to the previously reported stretched -honeycomb domain structure for the crystal bulk. In the T phase our x-ray diffraction measurements of CDW wave vectors and examination of fine satellite structure surrounding CDW peaks conclusively demonstrate that the bulk domain pattern is striped. We find that the bulk and surface domain structures are identical. X-ray diffraction of the I phase reveals weak satellites near CDW peaks. The satellite structure indicates a short wavelength, periodic amplitude and phase modulation of the CDW in a case where the CDW is far from commensurability. We measure the resistive superconducting transition temperature in C_{60} single crystals intercalated with isotopically pure ^{87}Rb and ^{85 }Rb and with natural abundance rubidium. We obtain a rubidium isotope effect exponent of alpha_{Rb} = -0.028 +/- 0.036, a result which implies that the Rb-C_ {60} optic phonons play at most a minor role in the pairing mechanism of Rb_3C _{60}..

  17. Utilizing Semantic Interpretation of Junctions for 3D-2D Pose Estimation

    DEFF Research Database (Denmark)

    Pilz, Florian; Yan, Shi; Grest, Daniel


    In this paper we investigate the quality of 3D-2D pose estimates using hand labeled line and point correspondences. We select point correspondences from junctions in the image, allowing to construct a meaningful interpretation about how the junction is formed, as proposed in e.g. [1], [2], [3]. W...

  18. Arabidopsis and Musa cyclin D2 expressed in banana (cv. “Sukali ...

    African Journals Online (AJOL)

    Genetic transformation of banana is important because of its polyploidy, sterility and long generation time of most cultivars which limit conventional breeding. However, transformability and regeneration of transgenic lines remains low in bananas. This research reports on the potential of CycD2 genes to improve ...

  19. 21 CFR 172.379 - Vitamin D2. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Vitamin D2. 172.379 Section 172.379 Food and Drugs... Dietary and Nutritional Additives § 172.379 Vitamin D2. Vitamin D2 may be used safely in foods as a... prescribed conditions: (a) Vitamin D2, also known as ergocalciferol, is the chemical 9,10-seco(5Z,7E,22E)-5,7...

  20. Rice Blast Resistance of Transgenic Rice Plants with Pi-d2 Gene

    Directory of Open Access Journals (Sweden)

    De-xi CHEN


    Full Text Available Resistance to rice blast of transgenic rice lines harboring rice blast resistance gene Pi-d2 transformed from three different expression vectors of pCB6.3kb, pCB5.3kb and pZH01-2.72kb were analyzed. Nine advanced-generation transgenic rice lines with Pi-d2 gene displayed various resistance to 39 rice blast strains, and the highest disease-resistant frequency reached 91.7%. Four early-generation homozygous transgenic lines with Pi-d2 gene exhibited resistance to more than 81.5% of 58 rice blast strains, showing the characteristic of wide-spectrum resistance. The transgenic embryonic calli selected by the crude toxin of rice blast fungus showed that the callus induction rate of immature embryo from transgenic rice plants decreased as the concentration of crude toxin in the culture medium increased. When the concentration of crude toxin reached 40%, the callus induction rate of immature embryo from transgenic lines was 49.3%, and that of the receptor control was 5%. The disease incidence of neck blast of the transgenic rice lines in fields under induction was 0% to 50%, indicating that the rice blast resistance of transgenic rice lines is much higher than that of the receptor control.

  1. Quantification of myocardial perfusion using cardiac magnetic resonance imaging correlates significantly to rubidium-82 positron emission tomography in patients with severe coronary artery disease

    DEFF Research Database (Denmark)

    Qayyum, Abbas A; Hasbak, Philip; Larsson, Henrik B W


    INTRODUCTION: Aim was to compare absolute myocardial perfusion using cardiac magnetic resonance imaging (CMRI) based on Tikhonov's procedure of deconvolution and rubidium-82 positron emission tomography (Rb-82 PET). MATERIALS AND METHODS: Fourteen patients with coronary artery stenosis underwent ...

  2. 3D/2D Registration of medical images

    NARCIS (Netherlands)

    Tomaževič, D.


    The topic of this doctoral dissertation is registration of 3D medical images to corresponding projective 2D images, referred to as 3D/2D registration. There are numerous possible applications of 3D/2D registration in image-aided diagnosis and treatment. In most of the applications, 3D/2D

  3. 26 CFR 1.1503(d)-2 - Domestic use. (United States)


    ... 26 Internal Revenue 12 2010-04-01 2010-04-01 false Domestic use. 1.1503(d)-2 Section 1.1503(d)-2...) INCOME TAXES Administrative Provisions and Other Rules § 1.1503(d)-2 Domestic use. A domestic use of a... offset, directly or indirectly, the income of a domestic affiliate (other than the dual resident...

  4. 21 CFR 582.5950 - Vitamin D2. (United States)


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Vitamin D2. 582.5950 Section 582.5950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5950 Vitamin D2. (a) Product. Vitamin D2. (b) Conditions of use. This substance is generally...

  5. Przebieg mitozy w korzeniach siewek pszenicy pod wpływem rubidu [Course of mitosis in root seedlings of Triticum aestivum L. under the influence of rubidium

    Directory of Open Access Journals (Sweden)

    Kazimierz Olech


    Full Text Available The depresion of mitosis as a result of rubidium action illustrated by the lower frequency of mitosis was found in an investigation made on roots of wheat seedlings grown on a nutrient medium which the total amount of potassium or a half of it was replaced by rubidium. The lower mitotic activity was caused by limited number of nuclei beginning prophase and by a prolonged duration of metaphase.

  6. α-RbO{sub 3}, a low temperature polymorph of rubidium ozonide

    Energy Technology Data Exchange (ETDEWEB)

    Sans, Annette; Nuss, Hanne; Jansen, Martin [Max Planck Institute for Solid State Research, Stuttgart (Germany); Mohitkar, Shrikant [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany)


    Applying the known procedure for synthesis of alkali metal ozonides, just at a lower temperature, has yielded a new polymorph of rubidium ozonide, α-RbO{sub 3} [P2{sub 1}; a = 436.3(2), b = 595.3(3), c = 548.7(3) pm, β = 99.680(7), R = 0.0400, 1184 reflections]. Like previously reported β-RbO{sub 3}, the basic structural arrangement of anions and cations corresponds to the CsCl type of structure, however, the mutual orientation of the ozonide ions is different, in as much as one of the two terminal oxygen atoms is pointing to the adjacent bridging oxygen atom, forming a chain running along the b axis. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Production of rubidium Bose-Einstein condensate in an optically-plugged magnetic quadrupole trap

    CERN Document Server

    Zhang, Dong-Fang; Kong, Ling-Ran; Li, Kai; Jiang, Kai-Jun


    We have experimentally produced rubidium Bose-Einstein condensate in an optically-plugged magnetic quadrupole (OPQ) trap. A far blue-detuned focused laser beam with a wavelength of 532 nm is plugged in the center of the magnetic quadrupole trap to increase the number of trapped atoms and suppress the heating. A radio frequency (RF) evaporative cooling in the magneto-optical hybrid trap is applied to decrease the atom temperature into degeneracy. The atom number of the condensate is $1.2(0.4)\\times10^5$ and the temperature is below 100 nK. We have also studied characteristic behaviors of the condensate, such as phase space density (PSD), condensate fraction and anisotropic expansion.

  8. Dynamics of solvation and desolvation of rubidium attached to He nanodroplets

    Energy Technology Data Exchange (ETDEWEB)

    Vangerow, J. von; John, O.; Stienkemeier, F.; Mudrich, M., E-mail: [Physikalisches Institut, Universität Freiburg, 79104 Freiburg (Germany)


    The real-time dynamics of photoexcited and photoionized rubidium (Rb) atoms attached to helium (He) nanodroplets is studied by femtosecond pump-probe mass spectrometry. While excited Rb atoms in the perturbed 6p-state (Rb{sup *}) desorb off the He droplets, Rb{sup +} photoions tend to sink into the droplet interior when created near the droplet surface. The transition from Rb{sup +} solvation to full Rb{sup *} desorption is found to occur at a delay time τ ∼ 600 fs for Rb{sup *} in the 6pΣ-state and τ ∼ 1200 fs for the 6pΠ-state. Rb{sup +}He ions are found to be created by directly exciting bound Rb{sup *}He exciplex states as well as by populating bound Rb{sup +}He-states in a photoassociative ionization process.

  9. The blue light indicator in rubidium 5S-5P-5D cascade excitation (United States)

    Raja, Waseem; Ali, Md. Sabir; Chakrabarti, Alok; Ray, Ayan


    The cascade system has played an important role in contemporary research areas related to fields like Rydberg excitation, four wave mixing and non-classical light generation, etc. Depending on the specific objective, co or counter propagating pump-probe laser experimental geometry is followed. However, the stepwise excitation of atoms to states higher than the first excited state deals with increasingly much fewer number of atoms even compared to the population at first excited level. Hence, one needs a practical indicator to study the complex photon-atom interaction of the cascade system. Here, we experimentally analyze the case of rubidium 5S → 5P → 5D as a specimen of two-step excitation and highlight the efficacy of monitoring one branch, which emits 420 nm, of associated cascade decay route 5D → 6P → 5S, as an effective monitor of the coherence in the system.

  10. Accumulation of myoinositol and rubidium ions in galactose-exposed rat lens

    Energy Technology Data Exchange (ETDEWEB)

    Kawaba, T.; Cheng, H.M.; Kinoshita, J.H.


    When rat lens is incubated in 30 mM galactose overnight, the extent of accumulation of rubidium ions (Rb) and myoinositol (MI) are affected, as well as the Na-K ATPase activity. Rb accumulation and Na-K ATPase activity are only slightly affected compared to the dramatic drop in MI accumulation. These changes are completely abolished by sorbinil, which blocks polyol formation, or by rendering the galactose medium hypertonic to offset the osmotic effect of polyol formation. On the other hand, the addition of excess MI to the galactose medium had no effect on correcting these changes. The results obtained are consistent with the polyol-osmotic theory of sugar cataract formation.

  11. A rubidium Mx-magnetometer for measurements on solid state spins (United States)

    Arnold, Daniel; Siegel, Steven; Grisanti, Emily; Wrachtrup, Jörg; Gerhardt, Ilja


    The detection of environmental magnetic fields is well established by optically pumped atomic magnetometers. Another focus of magnetometry can be the research on magnetic or spin-active solid-state samples. Here we introduce a simple and compact design of a rubidium-based Mx magnetometer, which allows for hosting solid-state samples. The optical, mechanical, and electrical design is reported, as well as simple measurements which introduce the ground-state spin-relaxation time, the signal-to-noise ratio of a measurement, and subsequently the overall sensitivity of the magnetometer. The magnetometer is optimized for the most sensitive operation with respect to laser power and magnetic field excitation at the Larmor frequency.

  12. Rubidium-82 PET imaging is feasible in a rat myocardial infarction model

    DEFF Research Database (Denmark)

    Ghotbi, Adam Ali; Clemmensen, Andreas; Kyhl, Kasper


    BACKGROUND: Small-animal myocardial infarct models are frequently used in the assessment of new cardioprotective strategies. A validated quantification of perfusion using a non-cyclotron-dependent PET tracer would be of importance in monitoring response to therapy. We tested whether myocardial PET...... perfusion imaging is feasible with Rubidium-82 ((82)Rb) in a small-animal scanner using a rat myocardial infarct model. METHODS: 18 Sprague-Dawley rats underwent permanent coronary artery ligation (infarct group), and 11 rats underwent ischemia-reperfusion (reperfusion group) procedure. (82)Rb......-PET and magnetic resonance imaging (MRI) were conducted before and after the intervention. Perfusion was compared to both left ventricle ejection fraction (LVEF) and infarct size assessed by MRI. RESULTS: Follow-up global (82)Rb-uptake correlated significantly with infarct size (infarct group: r = -0.81, P

  13. A rubidium Mx-magnetometer for measurements on solid state spins. (United States)

    Arnold, Daniel; Siegel, Steven; Grisanti, Emily; Wrachtrup, Jörg; Gerhardt, Ilja


    The detection of environmental magnetic fields is well established by optically pumped atomic magnetometers. Another focus of magnetometry can be the research on magnetic or spin-active solid-state samples. Here we introduce a simple and compact design of a rubidium-based Mx magnetometer, which allows for hosting solid-state samples. The optical, mechanical, and electrical design is reported, as well as simple measurements which introduce the ground-state spin-relaxation time, the signal-to-noise ratio of a measurement, and subsequently the overall sensitivity of the magnetometer. The magnetometer is optimized for the most sensitive operation with respect to laser power and magnetic field excitation at the Larmor frequency.

  14. Underground design Laxemar, Layout D2

    Energy Technology Data Exchange (ETDEWEB)


    Laxemar candidate area is located in the province of Smaaland, some 320 km south of Stockholm. The area is located close to the shoreline of the Baltic Sea and is within the municipality of Oskarshamn, and immediately west of the Oskarshamn nuclear power plant and the Central interim storage facility for spent fuel (Clab). The easternmost part (Simpevarp subarea) includes the Simpevarp peninsula, which hosts the power plants and the Clab facility. The island of Aespoe, containing the Aespoe Hard Rock Laboratory is located some three kilometres northeast of the central parts of Laxemar. The Laxemar subarea covers some 12.5 km2, compared with the Simepvarp subarea, which is approximately 6.6 km2. The Laxemar candidate area has been investigated in stages, referred to as the initial site investigations (ISI) and the complete site investigations (CSI). These investigations commenced in 2002 and were completed in 2008. During the site investigations, several studies and design steps (D0, D1 and D2) were carried out to ensure that sufficient space was available for the 6,000-canister layout within the target volume at a depth of approximately 500 m. The findings from design Step D2 for the underground facilities including the access ramp, shafts, rock caverns in a Central Area, transport tunnels, and deposition tunnels and deposition holes are contained in this report. The layout for these underground excavations at the deposition horizon requires an area of 5.7 km2, and the total rock volume to be excavated is 3,008 x 103 m3 using a total tunnel length of approximately 115 km. The behaviour of the underground openings associated with this layout is expected to be similar to the behaviour of other underground openings in the Scandinavian shield at similar depths. The dominant mode of instability is expected to be structurally controlled wedge failure. Stability of the openings will be achieved with traditional underground rock support and by orienting the openings

  15. Story of rubidium-82 and advantages for myocardial perfusion PET imaging

    Directory of Open Access Journals (Sweden)

    Jean-Francois eChatal


    Full Text Available Rubidium-82 has a long story, starting in 1954. After preclinical studies in dogs showing that myocardial uptake of this radionuclide was directly proportional to myocardial blood flow, clinical studies were performed in the 80s leading to an approval in the USA in 1989. From that time thousands of patients have been tested and their results have been reported in 3 meta-analyses. Pooled patient-based sensitivity and specificity were respectively 0.91 and 0.90. By comparison with 99mTc-SPECT, 82Rb-PET had a much better diagnostic accuracy, especially in obese patients with BMI (Body Mass Index ≥30 kg/m2 (85% versus 67% with SPECT and in women with large breasts. A great advantage of 82Rb-PET is its capacity to accurately quantify myocardial blood flow. Quite importantly it has been recently shown that coronary flow reserve is associated with adverse cardiovascular events independently of luminal angiographic severity. Moreover coronary flow reserve is a functional parameter particularly useful in the estimate of microvascular dysfunction such as in diabetes mellitus. Due to the very short half-life of rubidium-82, the effective dose calculated for a rest/stress test is roughly equivalent to the annual natural exposure and even less when stress-only is performed with a low activity compatible with a good image quality with the last generation 3D PET scanners.There is still some debate on the relative advantages of 82Rb-PET with regard to 99mTc-SPECT. For the last ten years, great technological advances substantially improved performances of SPECT with its accuracy getting closer to this of 82Rb/PET. Currently the main advantages of PET are its capacity to accurately quantify myocardial blood flow and to deliver a low radiation exposure.

  16. Story of Rubidium-82 and Advantages for Myocardial Perfusion PET Imaging. (United States)

    Chatal, Jean-François; Rouzet, François; Haddad, Ferid; Bourdeau, Cécile; Mathieu, Cédric; Le Guludec, Dominique


    Rubidium-82 has a long story, starting in 1954. After preclinical studies in dogs showing that myocardial uptake of this radionuclide was directly proportional to myocardial blood flow (MBF), clinical studies were performed in the 80s leading to an approval in the USA in 1989. From that time, thousands of patients have been tested and their results have been reported in three meta-analyses. Pooled patient-based sensitivity and specificity were, respectively, 0.91 and 0.90. By comparison with (99m)Tc-SPECT, (82)Rb PET had a much better diagnostic accuracy, especially in obese patients with body mass index ≥30 kg/m(2) (85 versus 67% with SPECT) and in women with large breasts. A great advantage of (82)Rb PET is its capacity to accurately quantify MBF. Quite importantly, it has been recently shown that coronary flow reserve is associated with adverse cardiovascular events independently of luminal angiographic severity. Moreover, coronary flow reserve is a functional parameter particularly useful in the estimate of microvascular dysfunction, such as in diabetes mellitus. Due to the very short half-life of rubidium-82, the effective dose calculated for a rest/stress test is roughly equivalent to the annual natural exposure and even less when stress-only is performed with a low activity compatible with a good image quality with the last generation 3D PET scanners. There is still some debate on the relative advantages of (82)Rb PET with regard to (99m)Tc-SPECT. For the last 10 years, great technological advances substantially improved performances of SPECT with its accuracy getting closer to this of (82)Rb/PET. Currently, the main advantages of PET are its capacity to accurately quantify MBF and to deliver a low radiation exposure.

  17. Terahertz Spectroscopy and Global Analysis of the Bending Vibrations of Acetylene 12C2D2 (United States)

    Yu, Shanshan; Drouin, Brian J.; Pearson, John C.; Pickett, Herbert M.; Lattanzi, Valerio; Walters, Adam


    Two hundred and fifty-one 12C2D2 transitions have been measured in the 0.2-1.6 THz region of its ν5-ν4 difference band and 202 of them were observed for the first time. The accuracy of these measurements is estimated to be ranging from 50 kHz to 100 kHz. The 12C2D2 molecules were generated under room temperature by passing 120-150 mTorr D2O vapor through calcium carbide (CaC2) powder. A multistate analysis was carried out for the bending vibrational modes ν4 and ν5 of 12C2D2, which includes the lines observed in this work and prior microwave, far-infrared and infrared data on the pure bending levels. Significantly improved molecular parameters were obtained for 12C2D2 by adding the new measurements to the old data set, which had only 10 lines with microwave measurement precision. New frequency and intensity predictions have been made based on the obtained molecular parameters. The more precise measurements and new predictions reported here will support the analyses of astronomical observations by the future high-resolution spectroscopy telescopes such as Herschel, SOFIA, and ALMA, which will work in the terahertz spectral region.

  18. Demonstration of an excited-state Faraday anomalous dispersion optical filter at 1529 nm by use of an electrodeless discharge rubidium vapor lamp (United States)

    Sun, Qinqing; Hong, Yelong; Zhuang, Wei; Liu, Zhiwen; Chen, Jingbiao


    An excited-state Faraday anomalous dispersion optical filter (ESFADOF) operating on the rubidium 5P3/2-4D5/2 transition (1529.4 nm in vacuum) is demonstrated, which utilizes an electrodeless discharge lamp rather than a laser-pumped Rb vapor cell as in a traditional ESFADOF system. When the lamp operates in the red mode with 3.5 W radio-frequency driving power, a twin-peak line-shaped transmission spectrum is obtained, which has a maximum transmittance of 21.9% (without taking into account the system loss and fluorescence background). ESFADOF by exploiting the 5P3/2-4D3/2 transition (1529.3 nm in vacuum) is also explored. A single-peak transmission spectrum with a maximum transmittance of about 3% is achieved. The electrodeless discharge lamp based ESFADOF holds promise for realizing a compact, low-cost, and good long-term frequency-stabilized laser system for optical communication applications.

  19. The dopamine D2 receptor gene in lamprey, its expression in the striatum and cellular effects of D2 receptor activation.

    Directory of Open Access Journals (Sweden)

    Brita Robertson

    Full Text Available All basal ganglia subnuclei have recently been identified in lampreys, the phylogenetically oldest group of vertebrates. Furthermore, the interconnectivity of these nuclei is similar to mammals and tyrosine hydroxylase-positive (dopaminergic fibers have been detected within the input layer, the striatum. Striatal processing is critically dependent on the interplay with the dopamine system, and we explore here whether D2 receptors are expressed in the lamprey striatum and their potential role. We have identified a cDNA encoding the dopamine D2 receptor from the lamprey brain and the deduced protein sequence showed close phylogenetic relationship with other vertebrate D2 receptors, and an almost 100% identity within the transmembrane domains containing the amino acids essential for dopamine binding. There was a strong and distinct expression of D2 receptor mRNA in a subpopulation of striatal neurons, and in the same region tyrosine hydroxylase-immunoreactive synaptic terminals were identified at the ultrastructural level. The synaptic incidence of tyrosine hydroxylase-immunoreactive boutons was highest in a region ventrolateral to the compact layer of striatal neurons, a region where most striatal dendrites arborise. Application of a D2 receptor agonist modulates striatal neurons by causing a reduced spike discharge and a diminished post-inhibitory rebound. We conclude that the D2 receptor gene had already evolved in the earliest group of vertebrates, cyclostomes, when they diverged from the main vertebrate line of evolution (560 mya, and that it is expressed in striatum where it exerts similar cellular effects to that in other vertebrates. These results together with our previous published data (Stephenson-Jones et al. 2011, 2012 further emphasize the high degree of conservation of the basal ganglia, also with regard to the indirect loop, and its role as a basic mechanism for action selection in all vertebrates.

  20. The Dopamine D2 Receptor Gene in Lamprey, Its Expression in the Striatum and Cellular Effects of D2 Receptor Activation (United States)

    Robertson, Brita; Huerta-Ocampo, Icnelia; Ericsson, Jesper; Stephenson-Jones, Marcus; Pérez-Fernández, Juan; Bolam, J. Paul; Diaz-Heijtz, Rochellys; Grillner, Sten


    All basal ganglia subnuclei have recently been identified in lampreys, the phylogenetically oldest group of vertebrates. Furthermore, the interconnectivity of these nuclei is similar to mammals and tyrosine hydroxylase-positive (dopaminergic) fibers have been detected within the input layer, the striatum. Striatal processing is critically dependent on the interplay with the dopamine system, and we explore here whether D2 receptors are expressed in the lamprey striatum and their potential role. We have identified a cDNA encoding the dopamine D2 receptor from the lamprey brain and the deduced protein sequence showed close phylogenetic relationship with other vertebrate D2 receptors, and an almost 100% identity within the transmembrane domains containing the amino acids essential for dopamine binding. There was a strong and distinct expression of D2 receptor mRNA in a subpopulation of striatal neurons, and in the same region tyrosine hydroxylase-immunoreactive synaptic terminals were identified at the ultrastructural level. The synaptic incidence of tyrosine hydroxylase-immunoreactive boutons was highest in a region ventrolateral to the compact layer of striatal neurons, a region where most striatal dendrites arborise. Application of a D2 receptor agonist modulates striatal neurons by causing a reduced spike discharge and a diminished post-inhibitory rebound. We conclude that the D2 receptor gene had already evolved in the earliest group of vertebrates, cyclostomes, when they diverged from the main vertebrate line of evolution (560 mya), and that it is expressed in striatum where it exerts similar cellular effects to that in other vertebrates. These results together with our previous published data (Stephenson-Jones et al. 2011, 2012) further emphasize the high degree of conservation of the basal ganglia, also with regard to the indirect loop, and its role as a basic mechanism for action selection in all vertebrates. PMID:22563388

  1. Dynamic quantum molecular sieving separation of D2 from H2-D2 mixture with nanoporous materials. (United States)

    Niimura, Subaru; Fujimori, Toshihiko; Minami, Daiki; Hattori, Yoshiyuki; Abrams, Lloyd; Corbin, Dave; Hata, Kenji; Kaneko, Katsumi


    Quantum molecular sieving separability of D(2) from an H(2)-D(2) mixture was measured at 77 K for activated carbon fiber, carbon molecular sieve, zeolite and single wall carbon nanotube using a flow method. The amount of adsorbed D(2) was evidently larger than H(2) for all samples. The maximum adsorption ratio difference between D(2) and H(2) was 40% for zeolite (MS13X), yielding a selectivity for D(2) with respect to H(2) of 3.05.

  2. Measurement of the electric dipole moments for transitions to rubidium Rydberg states via Autler-Townes splitting

    Energy Technology Data Exchange (ETDEWEB)

    Piotrowicz, M J; MacCormick, C; Kowalczyk, A; Bergamini, S [Department of Physics and Astronomy, Open University, Walton Hall, Milton Keynes, MK6 7AA (United Kingdom); Beterov, I I; Yakshina, E A, E-mail:, E-mail: [Institute of Semiconductor Physics, Lavrentyeva Avenue 13, 630090 Novosibirsk (Russian Federation)


    We present the direct measurements of electric dipole moments for 5P{sub 3/2}{yields}nD{sub 5/2} transitions with 20rubidium atoms. The measurements were carried out in an ultracold sample via observation of the Autler-Townes splitting in a three-level ladder scheme, commonly used for two-photon excitation of Rydberg states. To the best of our knowledge, this is the first systematic measurement of the electric dipole moments for transitions from low excited states of rubidium to Rydberg states. Due to its simplicity and versatility, this method can be easily extended to other transitions and other atomic species with few constraints. The good agreement seen between the experimental results and the theory proves the reliability of the measurement method.

  3. Erratum to: Magnetic field-induced modification of selection rules for Rb D2 line monitored by selective reflection from a vapor nanocell. Eur. Phys. J. D 71: 216 (2017), DOI: 10.1140/epjd/e2017-80291-6 (United States)

    Klinger, Emmanuel; Sargsyan, Armen; Tonoyan, Ara; Hakhumyan, Grant; Papoyan, Aram; Leroy, Claude; Sarkisyan, David


    The two technical points below are corrected by this erratum: 1. The publisher apologizes for a technical problem occurring in the scale numbering of Figure 2. The figure is corrected below. [Figure not available: see fulltext.] 2. Page 6, line 14 of the Conclusion section " F g = 2, m F = -3 → F e = 4, m F = -2" should be replaced by " F g = 2, m F = -2 → F e = 4, m F = -1".

  4. IDH2 mutations in patients with D-2-hydroxyglutaric aciduria. (United States)

    Kranendijk, Martijn; Struys, Eduard A; van Schaftingen, Emile; Gibson, K Michael; Kanhai, Warsha A; van der Knaap, Marjo S; Amiel, Jeanne; Buist, Neil R; Das, Anibh M; de Klerk, Johannis B; Feigenbaum, Annette S; Grange, Dorothy K; Hofstede, Floris C; Holme, Elisabeth; Kirk, Edwin P; Korman, Stanley H; Morava, Eva; Morris, Andrew; Smeitink, Jan; Sukhai, Rám N; Vallance, Hilary; Jakobs, Cornelis; Salomons, Gajja S


    Heterozygous somatic mutations in the genes encoding isocitrate dehydrogenase-1 and -2 (IDH1 and IDH2) were recently discovered in human neoplastic disorders. These mutations disable the enzymes' normal ability to convert isocitrate to 2-ketoglutarate (2-KG) and confer on the enzymes a new function: the ability to convert 2-KG to d-2-hydroxyglutarate (D-2-HG). We have detected heterozygous germline mutations in IDH2 that alter enzyme residue Arg(140) in 15 unrelated patients with d-2-hydroxyglutaric aciduria (D-2-HGA), a rare neurometabolic disorder characterized by supraphysiological levels of D-2-HG. These findings provide additional impetus for investigating the role of D-2-HG in the pathophysiology of metabolic disease and cancer.

  5. Analyses of absorption distribution of a rubidium cell side-pumped by a Laser-Diode-Array (LDA) (United States)

    Yu, Hang; Han, Juhong; Rong, Kepeng; Wang, Shunyan; Cai, He; An, Guofei; Zhang, Wei; Yu, Qiang; Wu, Peng; Wang, Hongyuan; Wang, You


    A diode-pumped alkali laser (DPAL) has been regarded as one of the most potential candidates to achieve high power performances of next generation. In this paper, we investigate the physical properties of a rubidium cell side-pumped by a Laser-Diode-Array (LDA) in this study. As the saturated concentration of a gain medium inside a vapor cell is extremely sensitive to the temperature, the populations of every energy-level of the atomic alkali are strongly relying on the vapor temperature. Thus, the absorption characteristics of a DPAL are mainly dominated by the temperature distribution. In this paper, the temperature, absorption, and lasing distributions in the cross-section of a rubidium cell side-pumped by a LDA are obtained by means of a complicated mathematic procedure. Based on the original end-pumped mode we constructed before, a novel one-direction side-pumped theoretical mode has been established to explore the distribution properties in the transverse section of a rubidium vapor cell by combining the procedures of heat transfer and laser kinetics together. It has been thought the results might be helpful for design of a side-pumped configuration in a high-powered DPAL.

  6. Activity of rubidium and cesium in soybean looper (Lepidoptera: Noctuidae): insect feeding on cotton and soybean measured by elemental markers. (United States)

    Jost, Douglas J; Pitre, Henry N


    Uptake and translocation of the elemental markers rubidium (Rb) and cesium (Cs) within adult soybean looper, Pseudoplusia includens (Walker), were determined using atomic absorption spectrophotometry in the laboratory in various feeding and mating treatments. Neonates were tested to determine marker transfer from male and female adults fed rubidium chloride (RbCl)-treated artificial nectar, cesium chloride (CsCI)-treated artificial nectar, or both. All females contained detectable levels of Rb, Cs, or both, which were obtained either through direct feeding or via spermatophores. Rubidium was present in females at significantly greater levels than Cs. No significant differences in Rb levels were observed between feeding or spermatophore acquisitions. Most neonates had significantly higher levels of Rb than Cs. In a field cage study to evaluate adult feeding and oviposition behavior on blooming cotton and blooming soybean treated with RbCl and CsCl, respectively, more eggs contained Rb than Cs, indicating greater feeding on cotton nectar than soybean nectar, regardless of the host plant upon which eggs were laid. Females laid more eggs on blooming soybean than on blooming cotton. Higher levels of Rb in cotton than Cs in soybean were recorded and may be attributed to initial elemental marker quantities available to the insects. This study provides the support for the generalized observations that soybean looper infestations in soybean can be related to feeding activities by adults in cotton.

  7. Quality of Service Based NOMA Group D2D Communications

    Directory of Open Access Journals (Sweden)

    Asim Anwar


    Full Text Available Non-orthogonal multiple access (NOMA provides superior spectral efficiency and is considered as a promising multiple access scheme for fifth generation (5G wireless systems. The spectrum efficiency can be further enhanced by enabling device-to-device (D2D communications. In this work, we propose quality of service (QoS based NOMA (Q-NOMA group D2D communications in which the D2D receivers (DRs are ordered according to their QoS requirements. We discuss two possible implementations of proposed Q-NOMA group D2D communications based on the two power allocation coefficient policies. In order to capture the key aspects of D2D communications, which are device clustering and spatial separation, we model the locations of D2D transmitters (DTs by Gauss–Poisson process (GPP. The DRs are then considered to be clustered around DTs. Multiple DTs can exist in proximity of each other. In order to characterize the performance, we derive the Laplace transform of the interference at the probe D2D receiver and obtain a closed-form expression of its outage probability using stochastic geometry tools. The performance of proposed Q-NOMA group D2D communications is then evaluated and benchmarked against conventional paired D2D communications.

  8. Cyclin D2 is a critical mediator of exercise-induced cardiac hypertrophy. (United States)

    Luckey, Stephen W; Haines, Chris D; Konhilas, John P; Luczak, Elizabeth D; Messmer-Kratzsch, Antke; Leinwand, Leslie A


    A number of signaling pathways underlying pathological cardiac hypertrophy have been identified. However, few studies have probed the functional significance of these signaling pathways in the context of exercise or physiological pathways. Exercise studies were performed on females from six different genetic mouse models that have been shown to exhibit alterations in pathological cardiac adaptation and hypertrophy. These include mice expressing constitutively active glycogen synthase kinase-3β (GSK-3βS9A), an inhibitor of CaMK II (AC3-I), both GSK-3βS9A and AC3-I (GSK-3βS9A/AC3-I), constitutively active Akt (myrAkt), mice deficient in MAPK/ERK kinase kinase-1 (MEKK1 -/- ), and mice deficient in cyclin D2 (cyclin D2 -/- ). Voluntary wheel running performance was similar to NTG littermates for five of the mouse lines. Exercise induced significant cardiac growth in all mouse models except the cyclin D2 -/- mice. Cardiac function was not impacted in the cyclin D2 -/- mice and studies using a phospho-antibody array identified six proteins with increased phosphorylation (greater than 150%) and nine proteins with decreased phosphorylation (greater than 33% decrease) in the hearts of exercised cyclin D2 -/- mice compared to exercised NTG littermate controls. Our results demonstrate that unlike the other hypertrophic signaling molecules tested here, cyclin D2 is an important regulator of both pathologic and physiological hypertrophy. Impact statement This research is relevant as the hypertrophic signaling pathways tested here have only been characterized for their role in pathological hypertrophy, and not in the context of exercise or physiological hypertrophy. By using the same transgenic mouse lines utilized in previous studies, our findings provide a novel and important understanding for the role of these signaling pathways in physiological hypertrophy. We found that alterations in the signaling pathways tested here had no impact on exercise performance. Exercise

  9. Oxygen atom-induced D 2 and D 2O desorption on D/Si(1 1 1) surfaces (United States)

    Rahman, F.; Khanom, F.; Inanaga, S.; Tsurumaki, H.; Namiki, A.


    We studied reaction of oxygen atoms with D-terminated Si(1 1 1) surfaces from a desorption point of view. As the D (1 ML)/Si(1 1 1) surface was exposed to O atoms D 2 and D 2O molecules were found to desorb from the surface. The desorption kinetics of D 2 and D 2O molecules exhibited a feature characterized with a quick rate jump at the very beginning of O exposure, which was followed by a gradual increase with a delayed maximum and then by an exponential decrease. The O-induced D 2 desorption spectra as a function of Ts appeared to be very similar to the H-induced D 2 desorption spectrum from the D/Si(1 1 1) surfaces. Possible mechanisms for the O-induced desorption reactions were discussed.

  10. Dopamine D2-receptor blockade enhances decoding of prefrontal signals in humans. (United States)

    Kahnt, Thorsten; Weber, Susanna C; Haker, Helene; Robbins, Trevor W; Tobler, Philippe N


    The prefrontal cortex houses representations critical for ongoing and future behavior expressed in the form of patterns of neural activity. Dopamine has long been suggested to play a key role in the integrity of such representations, with D2-receptor activation rendering them flexible but weak. However, it is currently unknown whether and how D2-receptor activation affects prefrontal representations in humans. In the current study, we use dopamine receptor-specific pharmacology and multivoxel pattern-based functional magnetic resonance imaging to test the hypothesis that blocking D2-receptor activation enhances prefrontal representations. Human subjects performed a simple reward prediction task after double-blind and placebo controlled administration of the D2-receptor antagonist amisulpride. Using a whole-brain searchlight decoding approach we show that D2-receptor blockade enhances decoding of reward signals in the medial orbitofrontal cortex. Examination of activity patterns suggests that amisulpride increases the separation of activity patterns related to reward versus no reward. Moreover, consistent with the cortical distribution of D2 receptors, post hoc analyses showed enhanced decoding of motor signals in motor cortex, but not of visual signals in visual cortex. These results suggest that D2-receptor blockade enhances content-specific representations in frontal cortex, presumably by a dopamine-mediated increase in pattern separation. These findings are in line with a dual-state model of prefrontal dopamine, and provide new insights into the potential mechanism of action of dopaminergic drugs. Copyright © 2015 the authors 0270-6474/15/354104-08$15.00/0.

  11. Amphetamine Self-Administration Attenuates Dopamine D2 Autoreceptor Function (United States)

    Calipari, Erin S; Sun, Haiguo; Eldeeb, Khalil; Luessen, Deborah J; Feng, Xin; Howlett, Allyn C; Jones, Sara R; Chen, Rong


    Dopamine D2 autoreceptors located on the midbrain dopaminergic neurons modulate dopamine (DA) neuron firing, DA release, and DA synthesis through a negative-feedback mechanism. Dysfunctional D2 autoreceptors following repeated drug exposure could lead to aberrant DA activity in the ventral tegmental area (VTA) and projection areas such as nucleus accumbens (NAcc), promoting drug-seeking and -taking behavior. Therefore, it is important to understand molecular mechanisms underlying drug-induced changes in D2 autoreceptors. Here, we reported that 5 days of amphetamine (AMPH) self-administration reduced the ability of D2 autoreceptors to inhibit DA release in the NAcc as determined by voltammetry. Using the antibody-capture [35S]GTPγS scintillation proximity assay, we demonstrated for the first time that midbrain D2/D3 receptors were preferentially coupled to Gαi2, whereas striatal D2/D3 receptors were coupled equally to Gαi2 and Gαo for signaling. Importantly, AMPH abolished the interaction between Gαi2 and D2/D3 receptors in the midbrain while leaving striatal D2/D3 receptors unchanged. The disruption of the coupling between D2/D3 receptors and Gαi2 by AMPH is at least partially explained by the enhanced RGS2 (regulator of G-protein signaling 2) activity resulting from an increased RGS2 trafficking to the membrane. AMPH had no effects on the midbrain expression and trafficking of other RGS proteins such as RGS4 and RGS8. Our data suggest that midbrain D2/D3 receptors are more susceptible to AMPH-induced alterations. Reduced D2 autoreceptor function could lead to enhanced DA signaling and ultimately addiction-related behavior. RGS2 may be a potential non-dopaminergic target for pharmacological intervention of dysfunctional DA transmission and drug addiction. PMID:24513972

  12. Indirect modulation of dopamine D2 receptors as potential pharmacotherapy for schizophrenia: I. Adenosine agonists. (United States)

    Dixon, D A; Fenix, L A; Kim, D M; Raffa, R B


    To review preclinical and clinical information related to pharmacologic modulation of dopamine D2 receptors as potential novel antipsychotic therapy. Specifically, to summarize the data that suggest a modulatory action of adenosine A2A receptors on dopamine D2 receptors and, therefore, a possible rational role of adenosine A2A agonists as novel antipsychotic agents. Primary and review articles were identified by MEDLINE search (from 1966 to May 1998) and through secondary sources. All of the articles identified from the data sources were evaluated and all information deemed relevant was included in this review. For all of the older and many of the newer antipsychotic agents, there is a strong correlation between clinical antipsychotic activity and affinity for dopamine D2 receptors. Unfortunately, dopamine D2 receptors are believed to also be involved in the adverse effect profile of these agents. The indirect modulation of dopamine D2 receptors, rather than direct block, might produce antipsychotic effects without the usual adverse reactions. Several lines of evidence from animal studies suggest that the use of selective A2A agonists might represent a novel approach to the treatment of psychoses. Dopamine receptor modulation might represent a novel antipsychotic approach or adjunct therapy. The data regarding adenosine agonists (particularly selective A2A receptor agonists) are inconclusive at the present time. Direct clinical demonstration of effectiveness is required.

  13. Dopamine D2 receptors in the pathophysiology of insulin resistance

    NARCIS (Netherlands)

    Leeuw van Weenen, Judith Elisabeth de


    Extensive literature links the dopamine receptor D2 to insulin resistance and diabetes mellitus type 2. However, many aspects of the functional relationship remain unclear. In this thesis we focused on unraveling the characteristics of the interplay between dopamine D2 receptors and glucose

  14. Energy Efficiency of D2D Multi-User Cooperation. (United States)

    Zhang, Zufan; Wang, Lu; Zhang, Jie


    The Device-to-Device (D2D) communication system is an important part of heterogeneous networks. It has great potential to improve spectrum efficiency, throughput and energy efficiency cooperation of multiple D2D users with the advantage of direct communication. When cooperating, D2D users expend extraordinary energy to relay data to other D2D users. Hence, the remaining energy of D2D users determines the life of the system. This paper proposes a cooperation scheme for multiple D2D users who reuse the orthogonal spectrum and are interested in the same data by aiming to solve the energy problem of D2D users. Considering both energy availability and the Signal to Noise Ratio (SNR) of each D2D user, the Kuhn-Munkres algorithm is introduced in the cooperation scheme to solve relay selection problems. Thus, the cooperation issue is transformed into a maximum weighted matching (MWM) problem. In order to enhance energy efficiency without the deterioration of Quality of Service (QoS), the link outage probability is derived according to the Shannon Equation by considering the data rate and delay. The simulation studies the relationships among the number of cooperative users, the length of shared data, the number of data packets and energy efficiency.

  15. M-theory solutions invariant under D(2,1; γ) + D(2,1;γ)

    Energy Technology Data Exchange (ETDEWEB)

    Bachas, C. [Laboratoire de Physique Theorique de l' Ecole Normale Superieure Unite mixte (UMR 8549) du CNRS et de l' ENS, Paris (France); D' Hoker, E. [Department of Physics and Astronomy, University of California, Los Angeles, CA (United States); Estes, J. [Blackett Laboratory, Imperial College, London (United Kingdom); Krym, D. [Physics Department, New York City College of Technology, The City University of New York, Brooklyn, NY (United States)


    We simplify and extend the construction of half-BPS solutions to 11-dimensional supergravity, with isometry superalgebra D(2,1;γ) + D(2,1;γ). Their space-time has the form AdS{sub 3} x S{sup 3} x S{sup 3} warped over a Riemann surface Σ. It describes near-horizon geometries of M2 branes ending on, or intersecting with, M5 branes along a common string. The general solution to the BPS equations is specified by a reduced set of data (γ, h, G), where γ is the real parameter of the isometry superalgebra, and h and G are functions on Σ whose differential equations and regularity conditions depend only on the sign of γ. The magnitude of γ enters only through the map of h,G onto the supergravity fields, thereby promoting all solutions into families parametrized by vertical stroke γ vertical stroke. By analyzing the regularity conditions for the supergravity fields, we prove two general theorems: (i) that the only solution with a 2-dimensional CFT dual is AdS{sub 3} x S{sup 3} x S{sup 3} x R {sup 2}, modulo discrete identifications of the flat R {sup 2}, and (ii) that solutions with γ < 0 cannot have more than one asymptotic higher-dimensional AdS region. We classify the allowed singularities of h and G near the boundary of Σ, and identify four local solutions: asymptotic AdS{sub 4}/Z{sub 2} or AdS{sub 7}' regions; highly-curved M5-branes; and a coordinate singularity called the ''cap''. By putting these ''Lego'' pieces together we recover all known global regular solutions with the above symmetry, including the self-dual strings on M5 for γ <0, and the Janus solution for γ > 0, but now promoted to families parametrized by vertical stroke γ vertical stroke. We also construct exactly new regular solutions which are asymptotic to AdS{sub 4}/Z{sub 2} for γ < 0, and conjecture that they are a different superconformal limit of the self-dual string. Finally, we construct exactly γ > 0 solutions with highly curved M5

  16. Clozapine, a Fast-Off-D2 Antipsychotic (United States)


    Ever since clozapine was first synthesized and tested, it showed the unique property of having antipsychotic action but no Parkinson-like motor side effects. The antipsychotic basis of clozapine is to transiently occupy dopamine D2 receptors in the human striatum, in contrast to haloperidol and chlorpromazine, which have a prolonged occupation of D2 receptors. The chemical structure of clozapine facilitates a relatively rapid dissociation from D2 receptors. After short-term occupation of D2 receptors, peak neural activity raises synaptic dopamine, which then displaces clozapine. While clozapine also occupies other types of receptors, they may not have a significant role in preventing parkinsonism. Clozapine’s transient occupation of D2 receptors permits patients to move easily and comfortably. PMID:24219174

  17. Hydrogen bonding induced proton exchange reactions in dense D2-NH3 and D2-CH4 mixtures. (United States)

    Borstad, Gustav M; Yoo, Choong-Shik


    We have investigated high-pressure behaviors of simple binary mixtures of NH3 and D2 to 50 GPa and CH4 and D2 to 30 GPa using confocal micro-Raman spectroscopy. The spectral data indicate strong proton exchange reactions occur in dense D2-NH3 mixture, producing different isotopes of ammonia such as NH3, NH2D, NHD2, and ND3. In contrast, the proton exchange process in dense D2-CH4 mixture is highly limited, and no vibration feature is apparent for deuterated methane. The vibrational modes of H2 isotopes in D2-NH3 are blue shifted from those of pure H2 isotopes, whereas the modes of D2-CH4 show overall agreement with those in pure D2 and CH4. In turn, this result advocates the presence of strong repulsion and thereby internal pressure in D2-NH3 mixture, which are absent in D2-CH4. In fact, the bond length of hydrogen molecules in D2-NH3, calculated from the present spectral data, is shorter than that observed in pure hydrogen - supporting the enhanced intermolecular interaction in the mixture. Comparing the present spectral results with those previously observed in D2-H2O mixtures further suggests that the strength of repulsive interaction or the magnitude of internal pressure in the mixtures is proportional to the strength of hydrogen bonding in H2O, NH3, and CH4 in decreasing order. Hence, we suggest that the proton exchange is assisted by hydrogen bonding in these molecules.

  18. Low Dopamine D2 Receptor Increases Vulnerability to Obesity Via Reduced Physical Activity, Not Increased Appetitive Motivation. (United States)

    Beeler, Jeff A; Faust, Rudolf P; Turkson, Susie; Ye, Honggang; Zhuang, Xiaoxi


    The dopamine D2 receptor (D2R) has received much attention in obesity studies. Data indicate that D2R is reduced in obesity and that the TaqA1 D2R variant may be more prevalent among obese persons. It is often suggested that reduced D2R generates a reward deficiency and altered appetitive motivation that induces compulsive eating and contributes to obesity. Although dopamine is known to regulate physical activity, it is often neglected in these studies, leaving open the question of whether reduced D2R contributes to obesity through alterations in energy expenditure and activity. We generated a D2R knockdown (KD) mouse line and assessed both energy expenditure and appetitive motivation under conditions of diet-induced obesity. The KD mice did not gain more weight or show increased appetitive motivation compared with wild-type mice in a standard environment; however, in an enriched environment with voluntary exercise opportunities, KD mice exhibited dramatically lower activity and became more obese than wild-type mice, obtaining no protective benefit from exercise opportunities. These data suggest the primary contribution of altered D2R signaling to obesity lies in altered energy expenditure rather than the induction of compulsive overeating. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  19. Measurements of myocardial flow vs. extraction of rubidium under varying physiological conditions

    Energy Technology Data Exchange (ETDEWEB)

    Budinger, T.F.; Yano, Y.; Moyer, B.R.; Twitchell, J.A.; Brennan, K.M.; Huesman, R.H.


    The relationship between myocardial rubidium extraction (E) and flow (F) are well described by the single capillary model E = (1-exp(-PS/F)) with a permeability surface product PS = 0.87 cc/min/gm. Some effects of alkalosis and acidosis have been reported. Here the authors investigate the effects of dipyridamole, norepinephrine-atropine, exsanguination, pacing, ouabain and calcium on extraction using Rb-82 PET and Rb-86 acute studies with microspheres in dogs. Thoracotomies were performed for left atrial microsphere infusion. Anesthesia was by N/sub 2/O and methoxyflurane. The degree of exsanguination, drug levels administered and pacing rates were sufficient to produce flow modifications. Extraction was calculated by dividing FE from Rb observations by F from microsphere data. These results of extraction vs. flow do not show a significant dependence on the method used for flow modification. There was less than a 20% change in FE after an infusion of 0.04 mg/kg ouabain over 5 minutes in 3 replicate studies each on 4 dogs. An important finding not previously explained in flow vs. extraction studies is the occurrence of extraction values greater than 1.0 which is possible only if the distribution opportunities of small cations are greater than that of microspheres. This is equivalent to the well known hematocrit effect in small channels.

  20. A waveguide frequency converter connecting rubidium-based quantum memories to the telecom C-band. (United States)

    Albrecht, Boris; Farrera, Pau; Fernandez-Gonzalvo, Xavier; Cristiani, Matteo; de Riedmatten, Hugues


    Coherently converting the frequency and temporal waveform of single and entangled photons will be crucial to interconnect the various elements of future quantum information networks. Of particular importance is the quantum frequency conversion of photons emitted by material systems able to store quantum information, so-called quantum memories. There have been significant efforts to implement quantum frequency conversion using nonlinear crystals, with non-classical light from broadband photon-pair sources and solid-state emitters. However, solid state quantum frequency conversion has not yet been achieved with long-lived optical quantum memories. Here we demonstrate an ultra-low-noise solid state photonic quantum interface suitable for connecting quantum memories based on atomic ensembles to the telecommunication fibre network. The interface is based on an integrated-waveguide nonlinear device. We convert heralded single photons at 780 nm from a rubidium-based quantum memory to the telecommunication wavelength of 1,552 nm, showing significant non-classical correlations between the converted photon and the heralding signal.

  1. Observation of spontaneously generated coherence on absorption in rubidium atomic beam (United States)

    Tian, Si-Cong; Kang, Zhi-Hui; Wang, Chun-Liang; Wan, Ren-Gang; Kou, Jun; Zhang, Hang; Jiang, Yun; Cui, Hai-Ning; Gao, Jin-Yue


    We report the experimental observation of the effect of spontaneously generated coherence on absorption without the rigorous requirement of close-lying levels. The experiments are studied in both a four-level N-type and a four-level inverted-Y-type atomic system in a rubidium atomic beam. With the coupling and controlling field, the N-type system is equivalent to a system with three closely upper levels coupled to one lower level by the same vacuum modes. The quantum interference can induce two prominent and nearly transparent holes where the slope of the refractive index is very steep. This special situation could allow the simultaneous propagation of two weak pulses with different frequencies. When we tune the wavelength of the controlling field, the N-type system turns to be the inverted-Y atomic system. Under the two-photon resonance condition, the system is equivalent to a V-type system with two closely upper levels, and the interference can reduce one broad transparency window in the middle of the absorption spectrum. Besides we can control the number of the spontaneously decay channels by the detuning of the controlling field, thus the effect of spontaneously generated coherence can exist in three or two closely space levels.

  2. Nuclear structure studies of the neutron-rich Rubidium isotopes using Coulomb excitation

    CERN Multimedia

    Reiter, P; Blazhev, A A; Voulot, D; Meot, V H; Simpson, G S; Georgiev, G P; Gaudefroy, L; Roig, O

    We propose to study the properties of odd-mass neutron-rich rubidium isotopes by the Coulomb-excitation technique, using the Miniball array coupled to the REX-ISOLDE facility. The results from similar measurements from the recent years (e.g. for the odd-mass and the odd-odd Cu isotopes, IS435) have shown the strong potential in such measurements for gaining information both for single-particle-like and collective states in exotic nuclei. Since there is practically no experimental information for excited states in the odd-mass Rb isotopes beyond $^{93}$Rb, the present study should be able to provide new data in a region of spherical ($^{93}$Rb and $^{95}$Rb) as well as well-deformed nuclei ($^{97}$Rb and $^{99}$Rb). Of particular interest is the rapid shape change that occurs when going from $^{95}$Rb (${\\varepsilon}_{2}$=0.06) to $^{97}$Rb (${\\varepsilon}_{2}$=0.3). These results should be of significant astrophysical interest as well, due to the close proximity of the r-process path.

  3. Absolute experimental cross sections for the electron impact ionization of rubidium. Technical summary report

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, D.W.; Feeney, R.K.


    The absolute cross sections for the double, triple, and quadruple ionization of Rb/sup +/ ions by electron impact have been measured from below their respective thresholds to approximately 3000 eV. This determination has been accomplished using a crossed beam facility in which monoenergetic beams of ions and electrons are caused to intersect at right angles in a well-defined collision volume. Multiply charged, product ions born as a result of the electron impact are deflected into their respective detectors by cascaded electrostatic analyzers. The multiply charged beam current component is measured by means of a vibrating reed electrometer operating in the rate-of-charge mode. The required singly charged rubidium ions are produced in a thermionic ion source and pass through a series of focusing, collimating and deflecting structures before entering the interaction region. A thermionically generated, rectangular electron beam intercepts the target ions in a spatially designated collision volume. Just prior to entering this interaction region the two beams can be made to pass through a movable slit scanner which determines their spatial profiles. The various charged particle currents, energies and beam current density distributions represent the experimental data from which the desired absolute cross sections have been determined. The results obtained with this technique are compared with available theoretical predictions of the appropriate cross sections.

  4. Design of a Low Phase Noise VCO for Rubidium Atomic Frequency Standard

    Directory of Open Access Journals (Sweden)

    Ju Qingyun


    Full Text Available Compared to the size and the power consumption of the traditional atomic clocks, the ones based on coherent population trapping (CPT can provide improvement by two orders of magnitude in both aspects above, making them needed urgently in many fields. Among different CPT atomic clocks, the one made with the rubidium atom are used widely, and their operating performance largely depends on its internal voltage-controlled oscillator (VCO which is used to provide a proper microwave signal. Based on this, a small size and low phase noise 3.035GHz VCO is designed with a modified Clapp circuit topology using low-cost surface-mount components, including a coaxial resonant (COAX with high quality factor. The designed VCO is simulated and optimized with the combined use of the negative resistance analysis method and the transmission analysis with a virtual-ground. In order to obtain the desired results, different values of key capacitor elements are tried according to their concrete influences on the VCO during the process of the circuit tuning. The test results show that the phase noises of the VCO are -60.49dBc/Hz@300Hz, -73.08dBc/Hz@1KHz and -97.48dBc/Hz@10KHz, the output power is -1.13dBm and the voltage-controlled tuning sensitivity is about 12MHz/V.

  5. Extrastriatal dopamine D2-receptor availability in social anxiety disorder. (United States)

    Plavén-Sigray, Pontus; Hedman, Erik; Victorsson, Pauliina; Matheson, Granville J; Forsberg, Anton; Djurfeldt, Diana R; Rück, Christian; Halldin, Christer; Lindefors, Nils; Cervenka, Simon


    Alterations in the dopamine system are hypothesized to influence the expression of social anxiety disorder (SAD) symptoms. However, molecular imaging studies comparing dopamine function between patients and control subjects have yielded conflicting results. Importantly, while all previous investigations focused on the striatum, findings from activation and blood flow studies indicate that prefrontal and limbic brain regions have a central role in the pathophysiology. The objective of this study was to investigate extrastriatal dopamine D2-receptor (D2-R) availability in SAD. We examined 12 SAD patients and 16 healthy controls using positron emission tomography and the high-affinity D2-R radioligand [ 11 C]FLB457. Parametric images of D2-R binding potential were derived using the Logan graphical method with cerebellum as reference region. Two-tailed one-way independent ANCOVAs, with age as covariate, were used to examine differences in D2-R availability between groups using both region-based and voxel-wise analyses. The region-based analysis showed a medium effect size of higher D2-R levels in the orbitofrontal cortex (OFC) in patients, although this result did not remain significant after correction for multiple comparisons. The voxel-wise comparison revealed elevated D2-R availability in patients within OFC and right dorsolateral prefrontal cortex after correction for multiple comparisons. These preliminary results suggest that an aberrant extrastriatal dopamine system may be part of the disease mechanism in SAD. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. 3D/2D Registration of medical images


    Tomaževič, D.


    The topic of this doctoral dissertation is registration of 3D medical images to corresponding projective 2D images, referred to as 3D/2D registration. There are numerous possible applications of 3D/2D registration in image-aided diagnosis and treatment. In most of the applications, 3D/2D registration provides the location and orientation of the structures in a preoperative 3D CT or MR image with respect to intraoperative 2D X-ray images. The proposed doctoral dissertation tries to find origin...

  7. Genetic variants of dopamine D2 receptor impact heterodimerization with dopamine D1 receptor. (United States)

    Błasiak, Ewa; Łukasiewicz, Sylwia; Szafran-Pilch, Kinga; Dziedzicka-Wasylewska, Marta


    The human dopamine D2 receptor gene has three polymorphic variants that alter its amino acid sequence: alanine substitution by valine in position 96 (V96A), proline substitution by serine in position 310 (P310S) and serine substitution by cysteine in position 311 (S311C). Their functional role has never been the object of extensive studies, even though there is some evidence that their occurrence correlates with schizophrenia. The HEK293 cell line was transfected with dopamine D1 and D2 receptors (or genetic variants of the D2 receptor), coupled to fluorescent proteins which allowed us to measure the extent of dimerization of these receptors, using a highly advanced biophysical approach (FLIM-FRET). Additionally, Fluoro-4 AM was used to examine changes in the level of calcium release after ligand stimulation of cells expressing different combinations of dopamine receptors. Using FLIM-FRET experiments we have shown that in HEK 293 expressing dopamine receptors, polymorphic mutations in the D2 receptor play a role in dimmer formation with the dopamine D1 receptor. The association level of dopamine receptors is affected by ligand administration, with variable effects depending on polymorphic variant of the D2 dopamine receptor. We have found that the level of heteromer formation is reflected by calcium ion release after ligand stimulation and have observed variations of this effect dependent on the polymorphic variant and the ligand. The data presented in this paper support the hypothesis on the role of calcium signaling regulated by the D1-D2 heteromer which may be of relevance for schizophrenia etiology. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  8. Quantitative imaging of D-2-hydroxyglutarate (D2HG in selected histological tissue areas by a novel bioluminescence technique

    Directory of Open Access Journals (Sweden)

    Nadine Fabienne Voelxen


    Full Text Available AbstractPatients with malignant gliomas have a poor prognosis with average survival of less than one year. Whereas in other tumor entities the characteristics of tumor metabolism are successfully used for therapeutic approaches, such developments are very rare in brain tumors, notably in gliomas. One metabolic feature characteristic of gliomas, in particular diffuse astrocytomas and oligodendroglial tumors, is the variable content of D-2-hydroxyglutarate (D2HG, a metabolite, which was discovered first in this tumor entity. D2HG is generated in large amounts due to various gain-of–function mutations in the isocitrate dehydrogenases IDH-1 and IDH-2. Meanwhile, D2HG has been detected in several other tumor entities including intrahepatic bile-duct cancer, chondrosarcoma, acute myeloid leukemia, and angioimmunoblastic T-cell lymphoma. D2HG is barely detectable in healthy tissue (< 0.1 mM, but its concentration increases up to 35 mM in malignant tumor tissues. Consequently, the oncometabolite D2HG has gained increasing interest in the field of tumor metabolism. To facilitate its quantitative measurement without loss of spatial resolution at a microscopical level, we have developed a novel bioluminescence assay for determining D2HG in sections of snap-frozen tissue. The assay was verified independently by photometric tests and liquid chromatography / mass spectrometry (LC/MS. The novel technique allows the microscopically resolved determination of D2HG in a concentration range of 0 – 10 µmol/g tissue (wet weight. In combination with the already established bioluminescence imaging techniques for ATP, glucose, pyruvate, and lactate, the novel D2HG assay enables a comparative characterization of the metabolic profile of individual tumors in a further dimension.

  9. Rubidium uptake of mononuclear leukocytes from normotensive and borderline hypertensive first degree relatives to patients with essential hypertension

    DEFF Research Database (Denmark)

    Johansen, Torben; Nielsen, J R; Poulsgård, L


    Uptake of 86Rubidium of mononuclear leukocytes (MNL) was used as a measure of cellular sodium-potassium pump activity. 86Rb-uptake was determined with the pump stimulated mainly from inside the cells by sodium as well as with a combined stimulation from inside by sodium and from outside by Rb....... In the first case there was an increased pump activity in MNL from borderline hypertensive offspring of hypertensive patients (BHO), and this may be related to an increased number of pump sites observed previously (10). Estimation of maximal pump activity (Vmax) of MNL suggested that Vmax of each pump site...

  10. Reduced striatal dopamine D2/3 receptor availability in Body Dysmorphic Disorder. (United States)

    Vulink, Nienke C; Planting, Robin S; Figee, Martijn; Booij, Jan; Denys, Damiaan


    Though the dopaminergic system is implicated in Obsessive Compulsive and Related Disorders (OCRD), the dopaminergic system has never been investigated in-vivo in Body Dysmorphic Disorder (BDD). In line with consistent findings of reduced striatal dopamine D2/3 receptor availability in Obsessive Compulsive Disorder (OCD), we hypothesized that the dopamine D2/3 receptor availability in the striatum will be lower in patients with BDD in comparison to healthy subjects. Striatal dopamine D2/3 receptor Binding Potential (BPND) was examined in 12 drug-free BDD patients and 12 control subjects pairwise matched by age, sex, and handedness using [(123)I]iodobenzamide Single Photon Emission Computed Tomography (SPECT; bolus/constant infusion technique). Regions of interest were the caudate nucleus and the putamen. BPND was calculated as the ratio of specific striatal to binding in the occipital cortex (representing nonspecific binding). Compared to controls, dopamine D2/3 receptor BPND was significantly lower in BDD, both in the putamen (p=0.017) and caudate nucleus (p=0.022). This study provides the first evidence of a disturbed dopaminergic system in BDD patients. Although previously BDD was classified as a separate disorder (somatoform disorder), our findings give pathophysiological support for the recent reclassification of BDD to the OCRD in DSM-5. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

  11. Rubidium extraction from seawater brine by an integrated membrane distillation-selective sorption system. (United States)

    Naidu, Gayathri; Jeong, Sanghyun; Johir, Md Abu Hasan; Fane, Anthony G; Kandasamy, Jaya; Vigneswaran, Saravanamuthu


    The ultimate goal of seawater reverse osmosis (SWRO) brine management is to achieve minimal liquid discharge while recovering valuable resources. The suitability of an integrated system of membrane distillation (MD) with sorption for the recovery of rubidium (Rb + ) and simultaneous SWRO brine volume reduction has been evaluated for the first time. Polymer encapsulated potassium copper hexacyanoferrate (KCuFC(PAN)) sorbent exhibited a good selectivity for Rb + sorption with 10-15% increment at 55 °C (Langmuir Q max  = 125.11 ± 0.20 mg/g) compared to at 25 °C (Langmuir Q max  = 108.71 ± 0.20 mg/g). The integrated MD-KCuFC(PAN) system with periodic membrane cleaning, enabled concentration of SWRO brine to a volume concentration factor (VCF) of 2.9 (65% water recovery). A stable MD permeate flux was achieved with good quality permeate (conductivity of 15-20 μS/cm). Repeated cycles of MD-KCuFC(PAN) sorption with SWRO brine enabled the extraction of 2.26 mg Rb + from 12 L of brine (equivalent to 1.9 kg of Rb/day, or 0.7 tonne/yr from a plant producing 10,000 m 3 /day brine). KCuFC(PAN) showed a high regeneration and reuse capacity. NH 4 Cl air stripping followed by resorcinol formaldehyde (RF) resin filtration enabled to recover Rb + from the desorbed solution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Measurement of Na-K-ATPase-mediated rubidium influx in single segments of rat nephron

    Energy Technology Data Exchange (ETDEWEB)

    Cheval, L.; Doucet, A. (Centre National de la Recherche Scientifique, Paris (France))


    To determine the functioning rate of Na-K-ATPase in the rat nephron, a micromethod was developed to measure the rate of rubidium uptake in single nephron segments microdissected from collagenase-treated kidneys. Because the hydrolytic activity of Na-K-ATPase displayed the same apparent affinity for K and Rb ions, whereas the Vmax elicited by K was higher than that in the presence of Rb, experiments were performed in the presence of cold Rb plus 86Rb. Before the assay, tubules were preincubated for 10 min at 37 degrees C to restore the normal transmembrane cation gradients. 86Rb uptake was measured after washing out extracellular cations by rinsing the tubules in ice-cold choline chloride solution containing Ba2+. Rb uptake increased quasi-linearly as a function of incubation time up to 30 s in the thick ascending limb, 1 min in the proximal convoluted tubule, and 5 min in the collecting tubule, and reached an equilibrium after 5-30 min. The initial rates of Rb uptake increased in a saturable fashion as Rb concentration in the medium rose from 0.25 to 5 mM. In medullary thick ascending limb, the initial rate of Rb uptake was inhibited by greater than 90% by 2.5 mM ouabain and by 10(-5) M of the metabolic inhibitor carbonyl cyanide trifluoromethoxyphenylhydrazone. Correlation of Na-K-ATPase hydrolytic activity at Vmax and initial rates of ouabain-sensitive Rb uptake in the successive segments of nephron indicates that in intact cells the pump works at approximately 20-30% of its Vmax. Increasing intracellular Na concentration by tubule preincubation in a Rb- and K-free medium increased the initial rates of Rb intake up to the Vmax of the hydrolytic activity of the pump.

  13. Quantitative measurement of rubidium isotope ratio using forward degenerate four-wave mixing

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Xuemei [State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, National Photoelectric Technology, and Functional Materials and Application of Science and Technology International Cooperation Center, Northwest University, Xi' an 710069 (China); Ren Zhaoyu, E-mail: [State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, National Photoelectric Technology, and Functional Materials and Application of Science and Technology International Cooperation Center, Northwest University, Xi' an 710069 (China); Wang Jian; Miao Yizhu [State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, National Photoelectric Technology, and Functional Materials and Application of Science and Technology International Cooperation Center, Northwest University, Xi' an 710069 (China); Xu Xinlong [State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, National Photoelectric Technology, and Functional Materials and Application of Science and Technology International Cooperation Center, Northwest University, Xi' an 710069 (China); Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Jia Lajiang [State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, National Photoelectric Technology, and Functional Materials and Application of Science and Technology International Cooperation Center, Northwest University, Xi' an 710069 (China); Fan Haiming, E-mail: [State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, National Photoelectric Technology, and Functional Materials and Application of Science and Technology International Cooperation Center, Northwest University, Xi' an 710069 (China); School of Physics, National University of Ireland Galway (NUIG), Galway (Ireland); and others


    In the present study, forward degenerate four-wave mixing (FDFWM) is employed to measure rubidium (Rb) isotope ratio quantitatively with excellent reproducibility regardless of laser intensity turbulence. The effects of power saturation, atomic absorption and Doppler broadening on measurements are investigated. The results indicate that optimized pump power for isotope ratio measurement is 5-37.3 mW and the optimized atomic number density is around 10{sup 14} m{sup -3} for the sample cell with a length of 50 mm. In addition, the signal of FDFWM is almost independent on Doppler effect in isotope ratio determination. The measured {sup 85}Rb and {sup 87}Rb ratios in Rb vapor cell and RbCl are 2.590 {+-} 0.001 and 2.649 {+-} 0.002 respectively, which are in good agreement with the values obtained by absorption spectroscopy and mass spectrometry. A low detection limit as 18.41 fg/mL is achieved. The information obtained from this work suggests that FDFWM is a reliable laser spectroscopic technique in quantitative isotope trace analysis for various applications such as geological and archeological dating. - Highlights: Black-Right-Pointing-Pointer Rb isotope ratio was quantitatively determined with DFWM for the first time. Black-Right-Pointing-Pointer Saturation effect and atomic absorption were studied to optimize the parameters. Black-Right-Pointing-Pointer High resolution was realized in graphite furnace with high temperature of 2000 Degree-Sign C. Black-Right-Pointing-Pointer Detection limit as low as 18.41 fg/mL was achieved.

  14. High-temperature phase transitions, spectroscopic properties, and dimensionality reduction in rubidium thorium molybdate family. (United States)

    Xiao, Bin; Gesing, Thorsten M; Kegler, Philip; Modolo, Giuseppe; Bosbach, Dirk; Schlenz, Hartmut; Suleimanov, Evgeny V; Alekseev, Evgeny V


    Four new rubidium thorium molybdates have been synthesized by high-temperature solid-state reactions. The crystal structures of Rb8Th(MoO4)6, Rb2Th(MoO4)3, Rb4Th(MoO4)4, and Rb4Th5(MoO4)12 were determined using single-crystal X-ray diffraction. All these compounds construct from MoO4 tetrahedra and ThO8 square antiprisms. The studied compounds adopt the whole range of possible structure dimensionalities from zero-dimensional (0D) to three-dimensional (3D): finite clusters, chains, sheets, and frameworks. Rb8Th(MoO4)6 crystallizes in 0D containing clusters of [Th(MoO4)6](8-). The crystal structure of Rb2Th(MoO4)3 is based upon one-dimensional chains with configuration units of [Th(MoO4)3](2-). Two-dimensional sheets occur in compound Rb4Th(MoO4)4, and a 3D framework with channels formed by thorium and molybdate polyhedra has been observed in Rb4Th5(MoO4)12. The Raman and IR spectroscopic properties of these compounds are reported. Temperature-depended phase transition effects were observed in Rb2Th(MoO4)3 and Rb4Th(MoO4)4 using thermogravimetry-differential scanning calorimetry analysis and high-temperature powder diffraction methods.

  15. Regadenoson pharmacologic rubidium-82 PET: a comparison of quantitative perfusion and function to dipyridamole. (United States)

    Cullom, S James; Case, James A; Courter, Staci A; McGhie, A Iain; Bateman, Timothy M


    Dipyridamole is used for stress (82)rubidium chloride ((82)RbCl) PET because of its long hyperemic duration. Regadenoson has advantages of a fixed dose and favorable symptom profile, but its mean maximal hyperemia is only 2.3 minutes. To determine its suitability for (82)RbCl PET, we imaged subjects using a regadenoson protocol based on its hyperemic response and compared the images in the same subjects having dipyridamole PET. In 32 subjects (23 M), we assessed visually by blinded interpretation and quantitatively compared summed stress and difference scores, total perfusion deficit (TPD), LVEF, LV volumes, and change in stress-rest function. Linear correlation and Bland-Altman analysis of the paired measurements were applied for evaluation of differences. Paired t test and Pearson's correlation were applied for testing of significance. The images were interpreted the same by visual assessment. Twenty-six (26) subjects had reversible defects; by quantitation the SSS was 12.9 ± 7.0 and 14.1 ± 6.4 (P = .23) and SDS was 7.0 ± 6.8 versus 7.6 ± 6.2 (P = .40) for dipyridamole and regadenoson, respectively. Six (6) subjects had regadenoson and dipyridamole; stress segmental perfusion Reg = 0.93Dip + 4.4, r = 0.88; TPD Reg = 0.94Dip + 0.41, r = 0.93; LVEF Reg = 0.92Dip + 4.7, r = 0.95; stress minus rest LVEF Reg = 0.87Dip - 0.99, r = 0.82. Regadenoson stress (82)RbCl PET perfusion defect and cardiac function measurements are visually and quantitatively equivalent to dipyridamole studies and can be obtained with the clinical advantages of regadenoson.

  16. Role of dopamine D2 receptors in human reinforcement learning. (United States)

    Eisenegger, Christoph; Naef, Michael; Linssen, Anke; Clark, Luke; Gandamaneni, Praveen K; Müller, Ulrich; Robbins, Trevor W


    Influential neurocomputational models emphasize dopamine (DA) as an electrophysiological and neurochemical correlate of reinforcement learning. However, evidence of a specific causal role of DA receptors in learning has been less forthcoming, especially in humans. Here we combine, in a between-subjects design, administration of a high dose of the selective DA D2/3-receptor antagonist sulpiride with genetic analysis of the DA D2 receptor in a behavioral study of reinforcement learning in a sample of 78 healthy male volunteers. In contrast to predictions of prevailing models emphasizing DA's pivotal role in learning via prediction errors, we found that sulpiride did not disrupt learning, but rather induced profound impairments in choice performance. The disruption was selective for stimuli indicating reward, whereas loss avoidance performance was unaffected. Effects were driven by volunteers with higher serum levels of the drug, and in those with genetically determined lower density of striatal DA D2 receptors. This is the clearest demonstration to date for a causal modulatory role of the DA D2 receptor in choice performance that might be distinct from learning. Our findings challenge current reward prediction error models of reinforcement learning, and suggest that classical animal models emphasizing a role of postsynaptic DA D2 receptors in motivational aspects of reinforcement learning may apply to humans as well.

  17. Pressure dependent isotopic fractionation in the photolysis of formaldehyde-d2

    DEFF Research Database (Denmark)

    Nilsson, E.J.K.; Schmidt, Johan Albrecht; Johnson, Matthew Stanley


    The isotope effects in formaldehyde photolysis are the key link between the δD of methane emissions and the δD of atmospheric in situ hydrogen production. A few recent studies have suggested that a pressure dependence in the isotopic fractionation can partly explain enrichment of deuterium...... earlier work with HDCO vs. H2CO. The UV lamps used for photolysis emit light at wavelengths that primarily dissociate formaldehyde into molecular products, CO and H2 or D2. The isotope effect k(H2CO)/k(D2CO) Combining double low line 3.16 ± 0.03 at 1000 mbar is in good agreement...... with results from previous studies. Similarly to what was previously shown for k(H2CO)/k(HDCO), the isotope effect decreased as pressure decreased. In addition, a model was constructed using RRKM theory to calculate the lifetime of excited formaldehyde on the S0 surface, to investigate its...

  18. Adsorption of Cesium, Strontium, and Rubidium radionuclides in the Mag-molecular process: The influence of important factors

    Directory of Open Access Journals (Sweden)

    Fatemeh Tangestani


    Full Text Available In this study, the adsorption of cesium, strontium, and rubidium radionuclides by ferritin magmolecules in a batch system was investigated under different experimental conditions. The experiments were conducted in a pilot plant that involved the contactor unit and the magnetic separator unit. The impact of the pollutant concentrations, adsorbent concentration, and pH on the efficiency of the process were investigated thoroughly. The maximum recovery of radionuclides in the studied domain were 57.05%, 85.42% and 71.82% for Cs+, Sr2+ and Rb+ ,respectively, in which the pollutant concentration was 363.63 mg/l, the adsorbent concentration was 0.011 g/l, and the pH was 7.5. The results showed that the ferritin adsorbent in the magmolecular process manifested a higher efficiency in adsorbing the bivalent ions of strontium compared to the univalent ions of cesium and rubidium. Furthermore, the results were statistically analyzed and the model and residual plots of each radionuclide were presented. The results also signified  relationships between the independent variables and recovery.

  19. A telecom-wavelength conversion from near-infrared light based on a cold Rubidium atomic ensemble (United States)

    Chang, Wei; Pu, Yunfei; Jiang, Nan; Li, Chang; Zhang, Sheng; Duan, Luming; Center for Quantum Information Lab4, IIIS, Tsinghua University Team


    Exponential photon transmission losses in fiber is a severe limitation to realize long-distance quantum communication. It's helpful to use telecom-wavelength photon transmission to mitigate these absorption losses. However, typical atomic electronic transition from ground-level is in visible wavelengths or near-infrared wavelengths, such as transitions based on Rubidium. Here we report our progress in telecom-wavelength conversion from 780nm to 1475nm and from 795nm to 1530nm in a cold optically thick gas of Rubidium. Both these two conversions are using a diamond configuration transition that we use 5S1/2-5P3/2-4D3/2 cascade transition for the 780nm to 1475nm route and 5S1/2-5P1/2-4D3/2 cascade transition for the 795nm to 1530nm route. This work was supported by the National Basic Research Program of China and the quantum information project from the Ministry of Education of China. LMD acknowledges in addition support from the IARPA MUSIQC program, the AFOSR and the ARO MURI program.

  20. Dissociable Rate-Dependent Effects of Oral Methylphenidate on Impulsivity and D2/3 Receptor Availability in the Striatum (United States)

    Caprioli, Daniele; Jupp, Bianca; Hong, Young T.; Sawiak, Stephen J.; Ferrari, Valentina; Wharton, Laura; Williamson, David J.; McNabb, Carolyn; Berry, David; Aigbirhio, Franklin I.; Robbins, Trevor W.; Fryer, Tim D.


    We have previously shown that impulsivity in rats is linked to decreased dopamine D2/3 receptor availability in the ventral striatum. In the present study, we investigated, using longitudinal positron emission tomography (PET), the effects of orally administered methylphenidate (MPH), a first-line treatment for attention deficit hyperactivity disorder, on D2/3 receptor availability in the dorsal and ventral striatum and related these changes to impulsivity. Rats were screened for impulsive behavior on a five-choice serial reaction time task. After a baseline PET scan with the D2/3 ligand [18F]fallypride, rats received 6 mg/kg MPH, orally, twice each day for 28 d. Rats were then reassessed for impulsivity and underwent a second [18F]fallypride PET scan. Before MPH treatment, we found that D2/3 receptor availability was significantly decreased in the left but not the right ventral striatum of high-impulse (HI) rats compared with low-impulse (LI) rats. MPH treatment increased impulsivity in LI rats, and modulated impulsivity and D2/3 receptor availability in the dorsal and ventral striatum of HI rats through inverse relationships with baseline levels of impulsivity and D2/3 receptor availability, respectively. However, we found no relationship between the effects of MPH on impulsivity and D2/3 receptor availability in any of the striatal subregions investigated. These findings indicate that trait-like impulsivity is associated with decreased D2/3 receptor availability in the left ventral striatum, and that stimulant drugs modulate impulsivity and striatal D2/3 receptor availability through independent mechanisms. PMID:25740505

  1. MARVEL analysis of the rotational-vibrational states of the molecular ions H2D+ and D2H+. (United States)

    Furtenbacher, Tibor; Szidarovszky, Tamás; Fábri, Csaba; Császár, Attila G


    Critically evaluated rotational-vibrational line positions and energy levels, with associated critically reviewed labels and uncertainties, are reported for two deuterated isotopologues of the H3(+) molecular ion: H2D(+) and D2H(+). The procedure MARVEL, standing for Measured Active Rotational-Vibrational Energy Levels, is used to determine the validated levels and lines and their self-consistent uncertainties based on the experimentally available information. The spectral ranges covered for the isotopologues H2D(+) and D2H(+) are 5.2-7105.5 and 23.0-6581.1 cm(-1), respectively. The MARVEL energy levels of the ortho and para forms of the ions are checked against ones determined from accurate variational nuclear motion computations employing the best available adiabatic ab initio potential energy surfaces of these isotopologues. The number of critically evaluated, validated and recommended experimental (levels, lines) are (109, 185) and (104, 136) for H2D(+) and D2H(+), respectively. The lists of assigned MARVEL lines and levels and variational levels obtained for H2D(+) and D2H(+) as part of this study are deposited in the ESI to this paper.

  2. Generation of squeezed vacuum on cesium D2 line down to kilohertz range (United States)

    Tian, Jian-Feng; Zuo, Guan-Hua; Zhang, Yu-Chi; Li, Gang; Zhang, Peng-Fei; Zhang, Tian-Cai


    Not Available Project supported by the National Natural Science Foundation of China (Grant Nos. 11634008, 61227902, 11574187, and 11674203), the National Key Research and Development Program of China (Grant No. 2017YFA0304500), and the Fund of “1331 Project” Key Subjects Construction of Shanxi Province, China.

  3. Musical Expression with the D2MMG Interface

    DEFF Research Database (Denmark)

    Jensen, Karl Kristoffer; Graugaard, Lars


    Distribution in Multiple Musical Gestures (D2MMG) uses a robust interface for detecting simple drawing gestures. The gestures affect low- and high-level aspects of sound and music through inherent modes organized as primary and secondary gestures. This enables expressive live performance...... and improvisation with sequence creation where musical elements such as tonality, chromaticity, rhythm patterns, and melodical sequences can be affected in real-time. We introduce a utility for procedurally controlling note density and chordal alignment. Future papers will focus on D2MMG’s progressive learning...

  4. 26 CFR 1.1092(d)-2 - Personal property. (United States)


    ... regulated futures contract or an option on the stock index) and stock in an investment company whose... (CONTINUED) INCOME TAXES Wash Sales of Stock Or Securities § 1.1092(d)-2 Personal property. (a) Special rules for stock. Under section 1092(d)(3)(B), personal property includes any stock that is part of a...

  5. Association of Dopamine D2 Receptor Gene with Creative Ideation (United States)

    Yu, Qi; Zhang, Shun; Zhang, Jinghuan H.


    Although several studies suggest that dopamine D2 receptor (DRD2) gene may contribute to creativity, the relationship between DRD2 and creativity still needs to be further validated. To further test the relevance of DRD2 and creativity, this study explored the association between DRD2 and creative ideation in 483 unrelated healthy Chinese…

  6. F-box protein FBXL2 targets cyclin D2 for ubiquitination and degradation to inhibit leukemic cell proliferation (United States)

    Chen, Bill B.; Glasser, Jennifer R.; Coon, Tiffany A.; Zou, Chunbin; Miller, Hannah L.; Fenton, Moon; McDyer, John F.; Boyiadzis, Michael


    Hematologic maligancies exhibit a growth advantage by up-regulation of components within the molecular apparatus involved in cell-cycle progression. The SCF (Skip-Cullin1-F-box protein) E3 ligase family provides homeostatic feedback control of cell division by mediating ubiquitination and degradation of cell-cycle proteins. By screening several previously undescribed E3 ligase components, we describe the behavior of a relatively new SCF subunit, termed FBXL2, that ubiquitinates and destabilizes cyclin D2 protein leading to G0 phase arrest and apoptosis in leukemic and B-lymphoblastoid cell lines. FBXL2 expression was strongly suppressed, and yet cyclin D2 protein levels were robustly expressed in acute myelogenous leukemia (AML) and acute lymphoblastic leukemia (ALL) patient samples. Depletion of endogenous FBXL2 stabilized cyclin D2 levels, whereas ectopically expressed FBXL2 decreased cyclin D2 lifespan. FBXL2 did not bind a phosphodegron within its substrate, which is typical of other F-box proteins, but uniquely targeted a calmodulin-binding signature within cyclin D2 to facilitate its polyubiquitination. Calmodulin competes with the F-box protein for access to this motif where it bound and protected cyclin D2 from FBXL2. Calmodulin reversed FBXL2-induced G0 phase arrest and attenuated FBXL2-induced apoptosis of lymphoblastoid cells. These results suggest an antiproliferative effect of SCFFBXL2 in lymphoproliferative malignancies. PMID:22323446

  7. Infrared Spectra of Complexes Containing ACETYLENE-d2 (United States)

    Lauzin, Clément; Oliaee, J. Norooz; Moazzen-Ahmadi, N.; McKellar, A. R. W.


    Infrared spectra of the C_2D_2 dimer in the monomer νb{3} region (˜2439 wn) are observed by direct absorption using a rapid-scan tuneable diode laser spectrometer to probe a pulsed supersonic slit-jet expansion. We analyze the perpendicular K = 1-0 and 0-1 subbands of the vibrational mode involving the C_2D_2 monomer located at the top of the T-shaped dimer, but miss the parallel band involving the stem monomer vibration due to limited laser coverage. The results are consistent with previous work on acetylene dimers, but perturbations are much less evident than in the analogous infrared spectrum of C_2H_2. As expected, the tunneling splitting in the excited state (8 MHz) is much smaller than in the ground state (424 MHz). In the same region, we observe the H-bonded isomer of the C_2D_2-C_2H_2 dimer. This has not previously been observed, even though microwave spectra of almost every other conceivable deuterated isotopologue are known.B In addition to these acetylene dimers, our spectra also contain bands arising from impurities in the gas mixture which we assign to the C_2D_2-nitrogen and C_2D_2-water complexes [1] G.T. Fraser, R.D. Suenram, F.J. Lovas, A.S. Pine, J.T. Hougen, W.J. Lafferty, and J.S. Muenter, J. Chem. Phys. 89, 6028 (1988). [2] K. Matsumura, F.J. Lovas, and R.D. Suenram, J. Mol. Spectrosc. 150, 576 (1991)

  8. Effects of Lactobacillus acidophilus D2/CSL on laying hen performance

    Directory of Open Access Journals (Sweden)

    Luigi Guidobono Cavalchini


    Full Text Available In order to evaluate the effects of dietary addition of probiotic strain Lactobacillus acidophilus D2/CSL on hen performance and egg quality, 160 commercial Hy-Line Brown pullets, 17 weeks old, were divided in control group (C (N=80 and treated group (T (N=80, with 4 alternate replicates of 20 animals each per group. C was fed with a “standard diet”, whereas the T group received the same diet with an inclusion of 1x109 CFU kg-1 of Lactobacillus acidophilus D2/CSL (freeze dried cells. The experimental trial lasted 39 weeks after one week of acclimatization. Hen performance and egg quality (egg production, FCR, egg specific gravity, shell thickness, Haugh Units were recorded. The results show a higher overall egg production (P<0.01 and better FCR (Kg feed intake/Kg saleable eggs (P<0.05 in the T birds, but no statistically significant differences were observed in egg weight. The eggs from the T birds were characterized by a higher specific gravity (ESG (P<0.01 and albumen viscosity (Haugh Units (P<0.05. No significant differences in egg shell thickness were recorded. In conclusion, Lactobacillus acidophilus D2/CSL improved some important parameters in laying hen performance and egg quality.

  9. Characterization of dopamine D1 and D2 receptor-expressing neurons in the mouse hippocampus. (United States)

    Gangarossa, Giuseppe; Longueville, Sophie; De Bundel, Dimitri; Perroy, Julie; Hervé, Denis; Girault, Jean-Antoine; Valjent, Emmanuel


    The hippocampal formation is part of an anatomical system critically involved in learning and memory. Increasing evidence suggests that dopamine plays an important role in learning and memory as well as in several forms of synaptic plasticity. However, the precise identification of neuronal populations expressing D1 or D2 dopamine receptors within the hippocampus is still lacking. To clarify this issue, we used BAC transgenic mice expressing enhanced green fluorescent protein (EGFP) under the control of the promoter of dopamine D1 or D2 receptors. In Drd1a-EGFP mice, sparse GFP-expressing neurons were detected among glutamatergic projecting neurons of the granular layer of the dentate gyrus and GABAergic interneurons located in the hilus. A dense immunofluorescence was observed in the outer and medial part of the molecular layer of the dentate gyrus as well as in the inner part of the molecular layer of CA1 corresponding to the terminals of pyramidal neurons of the entorhinal cortex defining the perforant and the temporo-ammonic pathway respectively. Finally, scattered D1 receptor-expressing neurons were also identified as GABAergic interneurons in the CA3/CA1 fields of the hippocampus. In Drd2-EGFP transgenic mice, GFP was exclusively detected in the glutamatergic mossy cells located in the polymorphic layer of the dentate gyrus. This pattern was confirmed in Drd2-Cre mice crossed with NLS-LacZ-Tau(mGFP) :LoxP and RCE:LoxP reporter lines. Our results demonstrate that D1 and D2 receptor-expressing neurons are strictly segregated in the mouse hippocampus. By clarifying the identity of D1 and D2 receptor-expressing neurons in the hippocampus, this study establishes a basis for future investigations aiming at elucidating their roles in the hippocampal network. Copyright © 2012 Wiley Periodicals, Inc.

  10. The vacuolar H+ ATPase V0 subunit d2 is associated with chondrocyte hypertrophy and supports chondrocyte differentiation

    Directory of Open Access Journals (Sweden)

    Babatunde A. Ayodele


    Full Text Available Chondrocyte hypertrophy makes important contributions to bone development and growth. We have investigated a number of novel cartilage genes identified in a recent transcriptomic study to determine whether they are differentially expressed between different zones of equine foetal growth cartilage. Twelve genes (ATP6V0D2, BAK1, DDX5, GNB1, PIP4K2A, RAP1B, RPS7, SRSF3, SUB1, TMSB4, TPI1 and WSB2 were found to be more highly expressed in the zone of hypertrophic chondrocytes than in the reserve or proliferative zones, whereas FOXA3 and SERPINA1 were expressed at lower levels in the hypertrophic zone than in the reserve zone. ATP6V0D2, which encodes vacuolar H+ ATPase (V-ATPase V0 subunit d2 (ATP6V0D2, was selected for further study. Immunohistochemical analysis of ATP6V0D2 in growth cartilage showed stronger staining in hypertrophic than in reserve zone or proliferative chondrocytes. Expression of ATP6V0D2 mRNA and protein was up-regulated in the mouse chondrocytic ATDC5 cell line by conditions inducing expression of hypertrophy-associated genes including Col10a1 and Mmp13 (differentiation medium. In ATDC5 cells cultured in control medium, knockdown of Atp6v0d2 or inhibition of V-ATPase activity using bafilomycin A1 caused a decrease in Col2a1 expression, and in cells cultured in differentiation medium the two treatments caused a decrease in nuclear area. Inhibition of V-ATPase, but not Atp6v0d2 knockdown, prevented the upregulation of Col10a1, Mmp13 and Vegf by differentiation medium, while Atp6v0d2 knockdown, but not inhibition of V-ATPase, caused an increase in the number of ATDC5 cells cultured in differentiation medium. These observations identify ATP6V0D2 as a novel chondrocyte hypertrophy-associated gene. The results are consistent with roles for V-ATPase, both ATP6V0D2-dependent and -independent, in supporting chondrocyte differentiation and hypertrophy.

  11. Romans-mass-driven flows on the D2-brane

    Energy Technology Data Exchange (ETDEWEB)

    Guarino, Adolfo [Nikhef Theory Group,Science Park 105, 1098 XG Amsterdam (Netherlands); Tarrío, Javier [Physique Théorique et Mathématique, Université Libre de Bruxellesand International Solvay Institutes,ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Varela, Oscar [Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut),Am Mühlenberg 1, D-14476 Potsdam (Germany); Department of Physics, Utah State University,Logan, UT 84322 (United States)


    The addition of supersymmetric Chern-Simons terms to N=8 super-Yang-Mills theory in three-dimensions is expected to make the latter flow into infrared superconformal phases. We address this problem holographically by studying the effect of the Romans mass on the D2-brane near-horizon geometry. Working in a consistent, effective four-dimensional setting provided by D=4N=8 supergravity with a dyonic ISO(7) gauging, we verify the existence of a rich web of supersymmetric domain walls triggered by the Romans mass that interpolate between the (four-dimensional description of the) D2-brane and various superconformal phases. We also construct domain walls for which both endpoints are superconformal. While most of our results are numerical, we provide analytic results for the SU(3)×U(1)-invariant flow into an N=2 conformal phase recently discovered.

  12. Deliverable D2.1. Stakeholder report: Identification & analysis


    Erdmann, Lorenz; Eckartz, Katharina; Moller, Björn; Tercero Espinoza, Luis A.; Teufel, Benjamin; Fuchs, Maureen; Machacek, Erika; Thorsøe, Kisser; Petavratzi, Evi; Brown, Teresa; Voet, Ester van der; Falck, Eberhard; Bisevac, Vanja; Hofmeister, Tobias; Quental, Lídia


    Deliverable D2.1 of the Mineral Capacity Intelligence Analysis (MICA) project documents the stakeholder landscape related to raw material intelligence. The main purpose is to provide a comprehensive inventory of relevant stakeholders to prepare for a systematic appraisal of stakeholder needs and to inform other Work Packages of the MICA project. The aim and ambition of the MICA project is to contribute to the emerging raw materials knowledge infrastructure in Europe (section 1). Stakeholder g...

  13. Symmetries and String Field Theory in D=2


    Kaku, Michio


    (This talk was presented at the Third International Wigner Symposium on Group Theory, Oxford, September, 1993.) Matrix models provides us with the most powerful framework in which to analyze D=2 string theory, yet some of its miraculous features, such as discrete states and $w(\\infty)$, remain rather obscure, because the string degrees of freedom have been removed. Liouville theory, on the other hand, has all its string degrees of freedom intact, yet is notoriously difficult to solve. In this...

  14. Neutron and high-pressure X-ray diffraction study of hydrogen-bonded ferroelectric rubidium hydrogen sulfate. (United States)

    Binns, Jack; McIntyre, Garry J; Parsons, Simon


    The pressure- and temperature-dependent phase transitions in the ferroelectric material rubidium hydrogen sulfate (RbHSO4) are investigated by a combination of neutron Laue diffraction and high-pressure X-ray diffraction. The observation of disordered O-atom positions in the hydrogen sulfate anions is in agreement with previous spectroscopic measurements in the literature. Contrary to the mechanism observed in other hydrogen-bonded ferroelectric materials, H-atom positions are well defined and ordered in the paraelectric phase. Under applied pressure RbHSO4 undergoes a ferroelectric transition before transforming to a third, high-pressure phase. The symmetry of this phase is revised to the centrosymmetric space group P21/c, resulting in the suppression of ferroelectricity at high pressure.

  15. Structure determination, electronic and optical properties of rubidium holmium polyphosphate RbHo(PO3)4 (United States)

    Zhu, Jing; Chen, Hui; Wang, Yude; Guan, Hongtao; Xiao, Xuechun


    Structural, optical, and electronic properties of a new alkali metal-rare earth polyphosphate, RbHo(PO3)4, have been investigated by means of single-crystal X-ray diffraction, power X-ray diffraction, elemental analysis, and spectral measurement. RbHo(PO3)4 crystallizes in the monoclinic with space group P21/n and Z = 4. It is described as a three-dimensional (3D) architecture built up of PO4 double spiral chains and HoO8 polyhedra by corner-sharing. The 11-coordinated rubidium atoms are located in infinite tunnels. Additionally, in order to gain further insight into the relationship between property and structure of RbHo(PO3)4, theoretical calculation based on the density functional theory (DFT) was performed using the total-energy code CASTEP.

  16. Control of rubidium low-lying Rydberg states with trichromatic femtosecond π pulses for ultrafast quantum information processing (United States)

    Afa, I. J.; Font, J. L.; Serrat, C.


    We propose an ultrafast femtosecond time scale trichromatic π -pulse illumination scheme for coherent excitation and manipulation of low-lying Rydberg states in rubidium. Selective population of nP 3 /2 levels with principal quantum numbers n ≲12 using 75-fs laser pulses is achieved. The density-matrix equations of a four-level ladder system beyond the rotating-wave approximation have to be solved to clarify the balance between the principal quantum numbers, the duration of the laser pulses, and the associated ac-Stark effects for the fastest optimal excitation. The mechanism is robust for femtosecond control using different level configurations for applications in ultrafast quantum information processing and spectroscopy.

  17. Deuterium NMR Investigation of the lyotropic phases of alkyl β-glycoside/D2O systems. (United States)

    Misran, Omar; Timimi, Bakir A; Heidelberg, Thorsten; Sugimura, Akihiko; Hashim, Rauzah


    We have investigated the phase behavior of four glycosides (βC8OGlc, βC8SGlc, βC10OGlc, βC8OGal) in water and D2O by optical polarizing microscopy and deuterium NMR. Previously published phase diagrams were evaluated by deuterium NMR, via monitoring D2O spectra, and confirmed the presence of the hexagonal, bicontinuous cubic, and lamellar phases in these glycosides. We have also shown the presence of the gel phase in (βC10OGlc) and observed the extensive supercooling of the lamellar phase to temperatures well below the Kraft line. While the main features of the phase diagrams were confirmed, some phase boundaries were found to be slightly different. Magnetically aligned spectra were also observed for relatively dilute samples for the hexagonal phase (βC8OGlc and βC8OGal) and the lamellar phase (βC8SGlc and βC10OGlc). The average number of bound water molecules per headgroup in the lamellar phase for the glycosides was determined by the systematic measurement of the quadrupolar splitting of D2O over a wide range of values of the (glycoside/water) molar ratio. The number of water molecules bound to the headgroup was found on average to be about 1.6-1.7 water molecules with no significant differences in this value for the different glycosides (and over the temperature range investigated), indicating that the bound water content is predominately influenced by the number of hydroxyl groups of the headgroup only. However, this bound water content of only 1.6-1.7 water molecules per sugar headgroup is surprisingly low, suggesting strong intermolecular interactions of the OH groups of headgroup sugars. The results are in line with computational results reported earlier for the octyl-β-glucoside and β-galactoside, which show the presence of strong intralayer hydrogen bonding.

  18. Voloshinite, a new rubidium mica from granitic pegmatite of Voron'i Tundras, Kola Peninsula, Russia (United States)

    Pekov, I. V.; Kononkova, N. N.; Agakhanov, A. A.; Belakovsky, D. I.; Kazantsev, S. S.; Zubkova, N. V.


    Voloshinite, a new mineral of the mica group, a rubidium analogue of lepidolite, has been found from the rare-element granitic pegmatite at Mt. Vasin-Myl'k, Voron'i Tundras, Kola Peninsula, Russia. It is closely associated with pollucite and lepidolite and commonly with muscovite, albite, and quartz; K,Rb-feldspar, rubicline, spodumene, montebrasite, and elbaite are among associated minerals as well. Voloshinite, a late mineral that formed after pollucite, commonly fills polymineralic veinlets and pods within the pollucite aggregates. It occurs as rims up to 0.05 mm thick around lepidolite, as intergrowths of tabular crystals up to 0.25 mm in size, and occasionally replaces lepidolite. The new mineral is colorless, transparent, with vitreous luster. Cleavage is eminent parallel to {001}; flakes are flexible. The calculated density is 2.95 g/cm3. The new mineral is biaxial (-), with 2 V = 25°, α calc = 1.511, β = 1.586, and γ = 1.590. The optical orientation is Y = b, Z = a. The chemical composition of the type material determined by electron microprobe (average of five point analyses; Li has been determined with ICP-OES) is as follows (wt %): 0.03 Na2O, 3.70 K2O, 12.18 Rb2O, 2.02 Cs2O, 4.0 Li2O, 0.03 CaO, 0.02 MgO, 0.14 MnO, 21.33 Al2O3, 53.14 SiO2, 6.41 F, -O = F2 2.70, total is 100.30. The empirical formula is: (Rb0.54K0.33Cs0.06)Σ0.93(Al1.42Li1.11Mn0.01)Σ2.54(Si3.68Al0.32)Σ4O10 (F1.40(OH)0.60)Σ2. The idealized formula is as follows: Rb(LiAl1.5□0.5)[Al0.5Si3.5O10]F2. Voloshinite forms a continuous solid solution with lepidolite. According to X-ray single crystal study, voloshinite is monoclinic, space group C2/ c. The unit-cell dimensions are: a = 5.191, b = 9.025, c = 20.40 Å, β = 95.37°, V= 951.5 Å3, Z = 4. Polytype is 2 M 1. The strongest reflections in the X-ray powder diffraction pattern ( d, Å- I[ hkl]) are: 10.1-60[001]; 4.55-80[020, 110, 11 bar 1 ]; 3.49-50[11 bar 4 ]; 3.35-60[024, 006]; 3.02-45[025]; 2.575-100[11 bar 6 , 131, 20 bar 2 , 13

  19. A new potential energy surface and microwave and infrared spectra of the Kr-D2O complex (United States)

    Wang, Zhongquan; Feng, Eryin; Zhang, Chunzao; Sun, Chunyan


    A four-dimensional potential energy surface of the Kr-D2O is calculated by the single and double excitation coupled-cluster theory with noniterative perturbational treatment of triple excitations [CCSD(T)], including explicit dependence on the ν2 bending vibrational Q2 normal coordinate of D2O. Using the fitted potential energy surface, the bound energy levels are calculated. The theoretical results for Π110 (v2 = 1) ← Σ101para bands of Kr-D2O rovibrational transition frequencies and the Π111 (ν2 = 1) ← Σ000 and the Σ111 (ν2 = 1) ← Σ000ortho bands are in good agreement with the observed values. The root mean square deviation is about 0.127 cm-1 for the 67 spectral lines.

  20. Genetic Transformation of Rice with Pi-d2 Gene Enhances Resistance to Rice Blast Fungus Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    De-xi CHEN


    Full Text Available The gene Pi-d2, conferring gene-for-gene resistance to the Chinese blast strain ZB15, was isolated from a rice variety (Digu by the map-based cloning strategy. Here, we constructed a control plasmid pZH01-pi-d2tp309 (pZH01-tp309 and three different expression constructs, pCB-Pi-d2 5.3kb (pCB5.3kb, pCB-Pi-d26.3kb (pCB6.3kb and pZH01-Pi-d22.72kb (pZH01-2.72kb of Pi-d2, driven by Pi-d2 gene's own promoter or CaMV35S promoter. These constructs were separately introduced into japonica rice varieties Lijiangxintuanhegu, Taipei 309, Nipponbare and Zhonghua 9 through Agrobacterium-mediated transformation. A total of 150 transgenic rice plants were obtained from the regenerated calli selected on hygromycin. PCR, RT-PCR and Southern-blotting assay showed that the gene of interest had been integrated into rice genome and stably inherited. Thirty-five transgenic lines independently derived from T1 progeny were inoculated with the rice blast strain ZB15. Transformants exhibited resistance to rice blast at various levels. The lesions on the transgenic plant leaves were less severe than those on the controls and the resistance level of transgenic plants harboring the gene of interest from three vectors had no difference. The own promoter of Pi-d2, about 2.2 kb or 3.2 kb, had the similar promoter function as CaMV35S. Field evaluation for three successive years supported the results of artificial trial, and some lines with high resistance to rice leaf blast and neck blast were obtained.

  1. Visualization of ligand-induced dopamine D2S and D2L receptor internalization by TIRF microscopy. (United States)

    Tabor, Alina; Möller, Dorothee; Hübner, Harald; Kornhuber, Johannes; Gmeiner, Peter


    G protein-coupled receptors (GPCRs), including the dopamine receptors, represent a group of important pharmacological targets. Upon agonist binding, GPCRs frequently undergo internalization, a process that is known to attenuate functional responses upon prolonged exposure to agonists. In this study, internalization was visualized by means of total internal reflection fluorescence (TIRF) microscopy at a level of discrete single events near the plasma membrane with high spatial resolution. A novel method has been developed to determine the relative extent of internalized fluorescent receptor-ligand complexes by comparative fluorescence quantification in living CHO cells. The procedure entails treatment with the reducing agent sodium borohydride, which converts cyanine-based fluorescent ligands on the membrane surface to a long-lived reduced form. Because the highly polar reducing agent is not able to pass the cell membrane, the fluorescent receptor-ligand complexes located in internalized compartments remain fluorescent under TIRF illumination. We applied the method to investigate differences of the short (D2S) and the long (D2L) isoforms of dopamine D2 receptors in their ability to undergo agonist-induced internalization.

  2. Immunohistochemical detection of dopamine D2 receptors in neuroendocrine tumours. (United States)

    Pawlikowski, Marek; Pisarek, Hanna; Winczyk, Katarzyna


    Recently, dopamine D2 receptors (RD2) have been found to be expressed in neuroendocrine tumours (NET), the tumours which arise from the diffuse neuroendocrine cells. Moreover, successful trials of the treatment of NET with cabergoline - D2 agonist, have been reported. These findings increase the interest of investigating RD2 expression in NET. The expression of RD2 was investigated immunohistochemically using the antibody which recognises both short (S) and long (L) isoforms of the receptor in 17 NET samples taken from 15 patients. In 17 NET samples, a positive reaction with the anti-RD2 antibody occurred in 11 cases. In six cases, the localisation of the immunostaining was cytoplasmic and in nine cases it was nuclear. Only in one case was the receptor cell membrane-located, and in two cases the immunoreaction was also localised in the blood vessels walls. The relation between RD2 expression and the grade of malignancy examined by means of Ki-67 antigen expression needs further study. However, preliminary observations indicate that the nuclear localisation of RD2 is linked to higher tumour malignancy. The next investigated question was the co-expression of somatostatin and dopamine receptors. This question seems important because of the perspectives of somatostatin-dopamine chimeras application in NET treatment. In the samples examined by us, RD2 were co-expressed in 5/10 cases with sstr1, in 3/10 with sstr2A, in 2/9 with sstr2B, in 3/10 with sstr3, and in 5/10 with sstr5. Dopamine D2 receptors are revealed by means of immunohistochemistry in the majority of NET. They exhibit cytoplasmic and/or nuclear localisations, the latter being possibly linked to a higher grade of malignancy, and are often co-expressed with somatostatin receptors (mostly with subtypes1 and 5).

  3. Improvements of AIMS D2DB matching for product patterns (United States)

    Nishiguchi, Masaharu; Kanno, Koichi; Miyashita, Hiroyuki; Ohara, Kana; Son, Donghwan; Tolani, Vikram; Satake, Masaki


    AIMSTM is mainly used in photomask industry for verifying the print impact of mask defects on wafer CD in DUV lithography process. AIMS verification is typically used in D2D configuration, wherein two AIMS images, reference and defect, are captured and compared. Criticality of defects is then analyzed off these images using a number of criteria. As photomasks with aggressive OPC, sub-resolution assist features (SRAFs), and single-die are being routinely manufactured in production environment, it is required to improve cycle time through the AIMS step by saving time in searching for and capturing an adequate reference AIMS image. One solution is to use AIMS D2DB methodology which compares AIMS defect image with a reference image simulated from the corresponding mask design data. In general, such simulation needs calibration with the native images captured on the AIMS tool. In our previous paper we evaluated a calibration procedure directly using the defect AIMS image and compared the analysis results with a D2D capture using AIA (Aerial Image Analyzer) software product from Luminescent Technologies (now part of KLA-Tencor Corporation). The results showed that calibration using defect AIMS image does not influence AIMS judgment as long as the defect size is less than 100nm in case of typical basic patterns. When applying this methodology to product patterns, it was found that there were differences between reference AIMS image and simulation image. These differences influenced AIMS verification. Then new method to compensate would be needed. Our approach to compensate the difference between AIMS image and simulated image is examination with some factors likely to cause the difference.

  4. Verification and Validation of D2FD Method


    Wang, Yan; Kaba Traoré, Mamadou; Zacharewicz, Grégory; Chen, David


    International audience; —D2FD (Data to Fuzzy-DEVS) method provides a solution for the problem of system inference. This method is well designed and implemented as an available and dedicated plug-in within the process mining framework (ProM). This plug-in is also integrated with the simulation tool SimStudio. However, the last step of the process of inferring models and simulations, which is verification and validation, is missing. This paper proposes a new paradigm of verification and validat...

  5. Rubidium 2,4,6-trioxo-1,3-diazinan-5-ide–1,3-diazinane-2,4,6-trione–water (1/1/1

    Directory of Open Access Journals (Sweden)

    Marlena Gryl


    Full Text Available The asymmetric unit of the title compound, Rb+·C4H3N2O3−·C4H4N2O3·H2O, consists of one rubidium cation, a barbituric acid molecule, a barbiturate anion and one water molecule. The rubidium ion has seven close-contact interactions with O atoms, with Rb...O distances ranging from 2.8594 (16 to 3.2641 (14 Å. These seven O atoms together with an eighth O atom at 3.492 (2 Å away from Rb form a distorted polyhedron with shape intermediate between an antiprism and a dodecahedron. The Rb+ ions connect layers built of organic components and water molecules linked via N—H...O and O—H...O hydrogen bonds.

  6. A Thy1-CFP DBA/2J mouse line with cyan fluorescent protein expression in retinal ganglion cells


    Raymond, Iona D.; POOL, ANGELA L.; Vila, Alejandro; Nicholas C Brecha


    A DBA/2J (D2) transgenic mouse line with cyan fluorescent protein (CFP) reporter expression in ganglion cells was developed for the analysis of ganglion cells during progressive glaucoma. The Thy1-CFP D2 (CFP-D2) line was created by congenically breeding the D2 line, which develops pigmentary glaucoma, and the Thy1-CFP line, which expresses CFP in ganglion cells. Microsatellite marker analysis of CFP-D2 progeny verified the genetic inclusion of the D2 isa and ipd loci. Specific mutations with...

  7. Phase separation in nH2- nD2 alloys (United States)

    Strzhemechny, M. A.; Prokhvatilov, A. I.; Shcherbakov, G. N.; Galtsov, N. N.


    Using powder x-ray technique we have studied the structure of solid mixtures of normal hydrogen and deuterium nH2- nD2, the samples being prepared by deposition from the gas onto a substrate at a temperature near 5 K. The content of nD2 in the alloys was varied from 0 to 100%. Over the range 20 to 85%, the diffraction patterns contain two sets of hep reflections, which correspond to phases rich in hydrogen and deuterium. As the temperature was raised to 12 14 K (depending on the composition), the separated alloys with comparatively fine crystallites started to show indications of growth and, simultaneously, homogenization, sometimes to completion. These states remained stable upon subsequent decreases in temperature. Analysis of the data supports the claim that phase separation occurs in nH2- nD2 alloys during sample preparation. This result confirms the finding by Kogan, Lazarev, and Bulatova. The characteristic points (kinks on the molar volume vs. composition, the position of the boundary of the homogenization area, etc.) are treated as belonging to lability rather than equilibrium lines. Proceeding from these arguments we reconstruct a hypothetical phase diagram which has the maximum separation temperature T c within the range 8 11 K. As shown using a model, which accounts for the electrical quadrupole (EQQ) interaction between J=1 species, the T c is substantially higher than predicted by Mullin and Sarin. We suggest some explanation for the striking difference between the results of different studies carried out to search for phase separation in solid mixtures of deuterium and hydrogen on samples prepared by different methods.

  8. SPECT imaging of D2 dopamine receptors and endogenous dopamine release in mice

    NARCIS (Netherlands)

    Jongen, C.; De Bruin, K.; Beekman, F.J.; Booij, J.


    Purpose: The dopamine D2 receptor (D2R) is important in the mediation of addiction. [123I]iodobenzamide (IBZM), a SPECT ligand for the D2R, has been used for in vivo studies of D2R availability in humans, monkeys, and rats. Although mouse models are important in the study of addiction, [123I]IBZM

  9. SPECT imaging of D-2 dopamine receptors and endogenous dopamine release in mice

    NARCIS (Netherlands)

    Jongen, Cynthia; de Bruin, Kora; Beekman, Freek; Booij, Jan


    Purpose The dopamine D-2 receptor (D2R) is important in the mediation of addiction. [I-123]iodobenzamide (IBZM), a SPECT ligand for the D2R, has been used for in vivo studies of D2R availability in humans, monkeys, and rats. Although mouse models are important in the study of addiction, [I-123]IBZM

  10. 16 CFR Appendix D2 to Part 305 - Water Heaters-Electric (United States)


    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Water Heaters-Electric D2 Appendix D2 to... PRODUCTS REQUIRED UNDER THE ENERGY POLICY AND CONSERVATION ACT (âAPPLIANCE LABELING RULEâ) Pt. 305, App. D2 Appendix D2 to Part 305—Water Heaters—Electric Range Information CAPACITY FIRST HOUR RATING Range of...

  11. M-theory solutions invariant under D(2,1; γ) ⊕ D(2,1;γ) (United States)

    Bachas, C.; D'Hoker, E.; Estes, J.; Krym, D.


    We simplify and extend the construction of half-BPS solutions to 11-dimensional supergravity, with isometry superalgebra D(2,1;\\gamma) \\oplus D(2,1;\\gamma). Their space-time has the form AdS_3 x S^3 x S^3 warped over a Riemann surface \\Sigma. It describes near-horizon geometries of M2 branes ending on, or intersecting with, M5 branes along a common string. The general solution to the BPS equations is specified by a reduced set of data (\\gamma, h, G), where \\gamma is the real parameter of the isometry superalgebra, and h and G are functions on \\Sigma whose differential equations and regularity conditions depend only on the sign of \\gamma. The magnitude of \\gamma enters only through the map of h, G onto the supergravity fields, thereby promoting all solutions into families parametrized by |\\gamma|. By analyzing the regularity conditions for the supergravity fields, we prove two general theorems: (i) that the only solution with a 2-dimensional CFT dual is AdS_3 x S^3 x S^3 x R^2, modulo discrete identifications of the flat R^2, and (ii) that solutions with \\gamma 0, but now promoted to families parametrized by |\\gamma|. We also construct exactly new regular solutions which are asymptotic to AdS_4/Z_2 for \\gamma < 0, and conjecture that they are a different superconformal limit of the self-dual string.

  12. The Asteroid Impact Mission - Deflection Demonstration (AIM - D2) (United States)

    Küppers, M.; Michel, P.; Carnelli, I.


    The Asteroid Impact Mission (AIM) is ESA's contribution to the international Asteroid Impact Deflection Assessment (AIDA) cooperation, targeting the demonstration of deflection of a hazardous near-earth asteroid. AIM will also be the first in-depth investigation of a binary asteroid and make measurements that are relevant for the preparation of asteroid resource utilisation. AIM is foreseen to rendezvous with the binary near-Earth asteroid (65803) Didymos and to observe the system before, during, and after the impact of NASA's Double Asteroid Redirection Test (DART) spacecraft. Here we describe the observations to be done by the simplified version Asteroid Impact Mission - Deflection Demonstration (AIM-D2) and show that most of the original AIM objectives can still be achieved.

  13. Inoenue-Wigner contraction and D = 2 + 1 supergravity

    Energy Technology Data Exchange (ETDEWEB)

    Concha, P.K.; Rodriguez, E.K. [Universidad Adolfo Ibanez, Departamento de Ciencias, Facultad de Artes Liberales, Vina del Mar (Chile); Universidad Austral de Chile, Instituto de Ciencias Fisicas y Matematicas, Valdivia (Chile); Fierro, O. [Universidad Catolica de la Santisima Concepcion, Departamento de Matematica y Fisica Aplicadas, Concepcion (Chile)


    We present a generalization of the standard Inoenue-Wigner contraction by rescaling not only the generators of a Lie superalgebra but also the arbitrary constants appearing in the components of the invariant tensor. The procedure presented here allows one to obtain explicitly the Chern-Simons supergravity action of a contracted superalgebra. In particular we show that the Poincare limit can be performed to a D = 2 + 1 (p,q) AdS Chern-Simons supergravity in presence of the exotic form. We also construct a new three-dimensional (2,0) Maxwell Chern-Simons supergravity theory as a particular limit of (2,0) AdS-Lorentz supergravity theory. The generalization for N = p + q gravitinos is also considered. (orig.)

  14. Cabergoline, dopamine D2 receptor agonist, prevents neuronal cell death under oxidative stress via reducing excitotoxicity. (United States)

    Odaka, Haruki; Numakawa, Tadahiro; Adachi, Naoki; Ooshima, Yoshiko; Nakajima, Shingo; Katanuma, Yusuke; Inoue, Takafumi; Kunugi, Hiroshi


    Several lines of evidence demonstrate that oxidative stress is involved in the pathogenesis of neurodegenerative diseases, including Parkinson's disease. Potent antioxidants may therefore be effective in the treatment of such diseases. Cabergoline, a dopamine D2 receptor agonist and antiparkinson drug, has been studied using several cell types including mesencephalic neurons, and is recognized as a potent radical scavenger. Here, we examined whether cabergoline exerts neuroprotective effects against oxidative stress through a receptor-mediated mechanism in cultured cortical neurons. We found that neuronal death induced by H₂O₂ exposure was inhibited by pretreatment with cabergoline, while this protective effect was eliminated in the presence of a dopamine D2 receptor inhibitor, spiperone. Activation of ERK1/2 by H₂O₂ was suppressed by cabergoline, and an ERK signaling pathway inhibitor, U0126, similarly protected cortical neurons from cell death. This suggested the ERK signaling pathway has a critical role in cabergoline-mediated neuroprotection. Furthermore, increased extracellular levels of glutamate induced by H₂O₂, which might contribute to ERK activation, were reduced by cabergoline, while inhibitors for NMDA receptor or L-type Ca²⁺ channel demonstrated a survival effect against H₂O₂. Interestingly, we found that cabergoline increased expression levels of glutamate transporters such as EAAC1. Taken together, these results suggest that cabergoline has a protective effect on cortical neurons via a receptor-mediated mechanism including repression of ERK1/2 activation and extracellular glutamate accumulation induced by H₂O₂.

  15. The barley (Hordeum vulgare) cellulose synthase-like D2 gene (HvCslD2) mediates penetration resistance to host-adapted and nonhost isolates of the powdery mildew fungus. (United States)

    Douchkov, Dimitar; Lueck, Stefanie; Hensel, Goetz; Kumlehn, Jochen; Rajaraman, Jeyaraman; Johrde, Annika; Doblin, Monika S; Beahan, Cherie T; Kopischke, Michaela; Fuchs, René; Lipka, Volker; Niks, Rients E; Bulone, Vincent; Chowdhury, Jamil; Little, Alan; Burton, Rachel A; Bacic, Antony; Fincher, Geoffrey B; Schweizer, Patrick


    Cell walls and cellular turgor pressure shape and suspend the bodies of all vascular plants. In response to attack by fungal and oomycete pathogens, which usually breach their host's cell walls by mechanical force or by secreting lytic enzymes, plants often form local cell wall appositions (papillae) as an important first line of defence. The involvement of cell wall biosynthetic enzymes in the formation of these papillae is still poorly understood, especially in cereal crops. To investigate the role in plant defence of a candidate gene from barley (Hordeum vulgare) encoding cellulose synthase-like D2 (HvCslD2), we generated transgenic barley plants in which HvCslD2 was silenced through RNA interference (RNAi). The transgenic plants showed no growth defects but their papillae were more successfully penetrated by host-adapted, virulent as well as avirulent nonhost isolates of the powdery mildew fungus Blumeria graminis. Papilla penetration was associated with lower contents of cellulose in epidermal cell walls and increased digestion by fungal cell wall degrading enzymes. The results suggest that HvCslD2-mediated cell wall changes in the epidermal layer represent an important defence reaction both for nonhost and for quantitative host resistance against nonadapted wheat and host-adapted barley powdery mildew pathogens, respectively. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  16. Lack of association between polymorphisms of dopamine receptors, type D2, and bipolar affective illness in a Polish population. (United States)

    Leszczyńska-Rodziewicz, Anna; Hauser, Joanna; Dmitrzak-Weglarz, Monika; Skibińka, Maria; Czerski, Piotr; Zakrzewska, Agnieszka; Kosmowska, Magdalena; Rybakowski, Janusz K


    Biochemical abnormalities are thought to be important factors causing bipolar disorder. Several lines of evidence suggest dopamine may play a role in its etiology, e.g. depressive syndrome is frequently encountered in subjects affected by Parkinson's disease, where dopamine depletion is observed. Thus the genes of the dopaminergic system are good candidates for studies on bipolar disorder. In the present study, we investigated polymorphisms of dopamine receptors, type D2, including the dopamine receptors D2, D3 and D4. Polish bipolar patients (n=339) and control subjects (n=366) were analyzed for three dopamine receptor gene polymorphisms: dopamine receptor D2 (DRD2) 141 ins/del, dopamine receptor D3 (DRD3) Ser9Gly, and dopamine receptor D4 (DRD4) 521 C/T. Allele and genotype frequencies did not differ significantly among patients and controls. We did not obtain any significant association between the studied polymorphisms and bipolar disorder. The results suggests that the studied gene variants of type D2 dopamine receptors are not promising candidate genes for bipolar affective illness. We did not consider the family history of the examined subjects, and also the control group was not psychiatrically screened, which may contribute to the lack of significant results.

  17. Emotional response in dopamine D2L receptor-deficient mice. (United States)

    Hranilovic, Dubravka; Bucan, Maja; Wang, Yanyan


    The dopamine D2 receptor (D2R) system has been implicated in emotional processing which is often impaired in neuropsychiatric disorders. The long (D2L) and the short (D2S) isoforms of D2R are generated by alternative splicing of the same gene. To study differential roles of the two D2R isoforms, D2L-deficient mice (D2L-/-) expressing functional D2S were previously generated. In this study the contribution of D2L isoform to emotional response was investigated by examining behaviors that reflect emotionality (exploratory behavior, anxiety-like behavior and learned helplessness) in D2L-/- and (wild-type) WT mice. While the thigmotactic, locomotor and general components of anxiety in zero maze did not differ among the genotypes, D2L-/- mice displayed significantly lower level of exploration in a hole board and zero maze, and significantly higher increase in latency to escape from a foot-shock after the learned helplessness training, compared with WT mice. These results suggest that D2L may play a more prominent role than D2S in mediating emotional response, such as behavioral reactions to novelty and inescapable stress. Our findings contribute to a better understanding of the molecular and cellular mechanisms underlying emotional responses.

  18. Myocardial blood flow assessment with 82rubidium-PET imaging in patients with left bundle branch block. (United States)

    Falcão, Andréa; Chalela, William; Giorgi, Maria Clementina; Imada, Rodrigo; Soares, José; Do Val, Renata; Oliveira, Marco Antonio; Izaki, Marisa; Kalil Filho, Roberto Kalil; Meneghetti, José C


    Perfusion abnormalities are frequently seen in Single Photon Emission Computed Tomography (SPECT) when a left bundle branch block is present. A few studies have shown decreased coronary flow reserve in the left anterior descending territory, regardless of the presence of coronary artery disease. We sought to investigate rubidium-82 (82Rb) positron emission tomography imaging in the assessment of myocardial blood flow and coronary flow reserve in patients with left bundle branch block. Thirty-eight patients with left bundle branch block (GI), median age 63.5 years, 22 (58%) female, 12 with coronary artery disease (≥70%; GI-A) and 26 with no evidence of significant coronary artery disease (GI-B), underwent rest-dipyridamole stress 82Rb-positron emission tomography with absolute quantitative flow measurements using Cedars-Sinai software (mL/min/g). The relative myocardial perfusion and left ventricular ejection fraction were assessed in 17 segments. These parameters were compared with those obtained from 30 patients with normal 82Rb-positron emission tomography studies and without left bundle branch block (GII). Stress myocardial blood flow and coronary flow reserve were significantly lower in GI than in GII (pbundle branch block had decreased myocardial blood flow and coronary flow reserve and coronary flow reserve assessed by 82Rb-positron emission tomography imaging may be useful in identifying coronary artery disease in patients with left bundle branch block.

  19. Production of transversely cooled, spin-polarized pulse beam from a low-velocity intense source of rubidium

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Eu Seok; Kim, Ji Yeon; Park, Chang Yong; Cho, D. [Korea University, Seoul (Korea, Republic of)


    In this experiment we studied the possibility of producing a pulsed beam for greater instantaneous beam flux, cooling the beam transversely to increase the effective beam flux and finally optical pumping to produce spin polarized atomic beam. We successfully and reliably produced a pulsed beam, and observed definite transverse cooling of the beam. We developed rather elaborate control program and interface hardware to produce the pulsed beam, and transversely cool, optically pump, and detect the atoms. We have produced the low-velocity intense source(LVIS) beam and operated it in a pulsed mode. Using an electronically controlled shutter we could load a Magneto Optical Trap(MOT) for 1 sec and launched a pulse of rubidium atoms. We performed the transverse cooling experiment using the pulses. In order to detect how the cooling is working, we used a slit to narrow down the probe beam. The probe beam had a width of 1 mm and we scanned it using a micrometer-controlled translational stage. (Cho, G.S.). 7 refs., 2 figs.

  20. Modeling of ligand binding to dopamine D2 receptor

    Directory of Open Access Journals (Sweden)

    Ostopovici-Halip Liliana


    Full Text Available The dopaminic receptors have been for long time the major targets for developing new small molecules with high affinity and selectivity to treat psychiatric disorders, neurodegeneration, drug abuse, and other therapeutic areas. In the absence of a 3D structure for the human D2 dopamine (HDD2 receptor, the efforts for discovery and design of new potential drugs rely on comparative models generation, docking and pharmacophore development studies. To get a better understanding of the HDD2 receptor binding site and the ligand-receptor interactions a homology model of HDD2 receptor based on the X-ray structure of β2-adrenergic receptor has been built and used to dock a set of partial agonists of HDD2 receptor. The main characteristics of the binding mode for the HDD2 partial agonists set are given by the ligand particular folding and a complex network of contacts represented by stacking interactions, salt bridge and hydrogen bond formation. The characterization of the partial agonist binding mode at HDD2 receptor provide the needed information to generate pharmacophore models which represent essential information in the future virtual screening studies in order to identify new potential HDD2 partial agonists.

  1. Thermodynamics of the localized D2-D6 system

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Reino, Marta [Martin Fisher School of Physics, Brandeis University, Waltham, MA 02454 (United States)]. E-mail:; Naculich, Stephen G. [Department of Physics, Bowdoin College, Brunswick, ME 04011 (United States)]. E-mail:; Schnitzer, Howard J. [Martin Fisher School of Physics, Brandeis University, Waltham, MA 02454 (United States)]. E-mail:


    An exact fully-localized extremal supergravity solution for N{sub 2} D2-branes and N{sub 6} D6-branes, which is dual to 3-dimensional supersymmetric SU(N{sub 2}) gauge theory with N{sub 6} fundamentals, was found by Cherkis and Hashimoto. In order to consider the thermal properties of the gauge theory we present the non-extremal extension of this solution to first order in an expansion near the core of the D6-branes. We compute the Hawking temperature and the black-brane horizon area/entropy. The leading-order entropy, which is proportional to N{sub 2}{sup 3/2}N{sub 6}{sup 1/2}T{sub H}{sup 2}, is not corrected to first order in the expansion. This result is consistent with the analogous weak-coupling result at the correspondence point N{sub 2} similar to N{sub 6}.

  2. Molecular Mapping of D1, D2 and ms5 Revealed Linkage between the Cotyledon Color Locus D2 and the Male-Sterile Locus ms5 in Soybean

    Directory of Open Access Journals (Sweden)

    Alina Ott


    Full Text Available In soybean, genic male sterility can be utilized as a tool to develop hybrid seed. Several male-sterile, female-fertile mutants have been identified in soybean. The male-sterile, female-fertile ms5 mutant was selected after fast neutron irradiation. Male-sterility due to ms5 was associated with the “stay-green” cotyledon color mutation. The cotyledon color trait in soybean is controlled by two loci, D1 and D2. Association between cotyledon color and male-sterility can be instrumental in early phenotypic selection of sterility for hybrid seed production. The use of such selection methods saves time, money, and space, as fewer seeds need to be planted and screened for sterility. The objectives of this study were to compare anther development between male-fertile and male-sterile plants, to investigate the possible linkages among the Ms5, D1 and D2 loci, and to determine if any of the d1 or d2 mutations can be applied in hybrid seed production. The cytological analysis during anther development displayed optically clear, disintegrating microspores and enlarged, engorged pollen in the male-sterile, female-fertile ms5ms5 plants, a common characteristic of male-sterile mutants. The D1 locus was mapped to molecular linkage group (MLG D1a and was flanked by Satt408 and BARCSOYSSR_01_1622. The ms5 and D2 loci were mapped to MLG B1 with a genetic distance ~12.8 cM between them. These results suggest that use of the d2 mutant in the selection of male-sterile line may attenuate the cost hybrid seed production in soybean.

  3. Effect of C-Terminal S-Palmitoylation on D2 Dopamine Receptor Trafficking and Stability.

    Directory of Open Access Journals (Sweden)

    Brittany Ebersole

    Full Text Available We have used bioorthogonal click chemistry (BCC, a sensitive non-isotopic labeling method, to analyze the palmitoylation status of the D2 dopamine receptor (D2R, a G protein-coupled receptor (GPCR crucial for regulation of processes such as mood, reward, and motor control. By analyzing a series of D2R constructs containing mutations in cysteine residues, we found that palmitoylation of the D2R most likely occurs on the C-terminal cysteine residue (C443 of the polypeptide. D2Rs in which C443 was deleted showed significantly reduced palmitoylation levels, plasma membrane expression, and protein stability compared to wild-type D2Rs. Rather, the C443 deletion mutant appeared to accumulate in the Golgi, indicating that palmitoylation of the D2R is important for cell surface expression of the receptor. Using the full-length D2R as bait in a membrane yeast two-hybrid (MYTH screen, we identified the palmitoyl acyltransferase (PAT zDHHC4 as a D2R interacting protein. Co-immunoprecipitation analysis revealed that several other PATs, including zDHHC3 and zDHHC8, also interacted with the D2R and that each of the three PATs was capable of affecting the palmitoylation status of the D2R. Finally, biochemical analyses using D2R mutants and the palmitoylation blocker, 2-bromopalmitate indicate that palmitoylation of the receptor plays a role in stability of the D2R.

  4. Vectorized ferrocenes with estrogens and vitamin D2: synthesis, cytotoxic activity and docking studies† (United States)

    Vera, José; Gao, Li Ming; Santana, Alberto; Matta, Jaime


    Three ferrocene complexes vectorized with estrogens and vitamin D2 were synthesized and fully characterized by spectroscopic, electrochemical and computational methods. The synthesis of these esters was accomplished by reacting ferrocenoyl chloride with the corresponding ROH groups (R = ergocalciferol, estradiol, estrone). The cytotoxicity of these complexes in HT-29 colon cancer and MCF-7 breast cancer cell lines was investigated in vitro. Only ferrocenoyl 17β-hydroxy-estra-1,3,5(10)-trien-3-olate showed good cytotoxic activity in both cell lines, exceeding those of ferrocenium and ferrocene. In MCF-7, ferrocenoyl 17β-hydroxy-estra-1,3,5(10)-trien-3-olate exhibited remarkable IC50, in the low micromolar range. This may be attributed to the presence of the estradiol vector. Docking studies between alpha-estrogen receptor ligand binding site and ferrocenoyl 17β-hydroxy-estra-1,3,5(10)-trien-3-olate revealed some key hydrophobic interactions that might explain the cytotoxic activity of this ester. PMID:21850331

  5. Microstructural Quantification of Rapidly Solidified Undercooled D2 Tool Steel (United States)

    Valloton, J.; Herlach, D. M.; Henein, H.; Sediako, D.


    Rapid solidification of D2 tool steel is investigated experimentally using electromagnetic levitation (EML) under terrestrial and reduced gravity conditions and impulse atomization (IA), a drop tube type of apparatus. IA produces powders 300 to 1400 μm in size. This allows the investigation of a large range of cooling rates ( 100 to 10,000 K/s) with a single experiment. On the other hand, EML allows direct measurements of the thermal history, including primary and eutectic nucleation undercoolings, for samples 6 to 7 mm in diameter. The final microstructures at room temperature consist of retained supersaturated austenite surrounded by eutectic of austenite and M7C3 carbides. Rapid solidification effectively suppresses the formation of ferrite in IA, while a small amount of ferrite is detected in EML samples. High primary phase undercoolings and high cooling rates tend to refine the microstructure, which results in a better dispersion of the eutectic carbides. Evaluation of the cell spacing in EML and IA samples shows that the scale of the final microstructure is mainly governed by coarsening. Electron backscattered diffraction (EBSD) analysis of IA samples reveals that IA powders are polycrystalline, regardless of the solidification conditions. EBSD on EML samples reveals strong differences between the microstructure of droplets solidified on the ground and in microgravity conditions. While the former ones are polycrystalline with many different grains, the EML sample solidified in microgravity shows a strong texture with few much larger grains having twinning relationships. This indicates that fluid flow has a strong influence on grain refinement in this system.

  6. D1 and D2 specific dopamine antagonist modulate the caudate nucleus neuronal responses to chronic methylphenidate exposure. (United States)

    Venkataraman, Sidish; Claussen, Catherine; Dafny, Nachum


    The psychostimulant, methylphenidate (MPD), is the first line treatment as a pharmacotherapy to treat behavioral disorders such as attention deficit hyperactivity disorder (ADHD). MPD is commonly misused in non-ADHD (normal) youth and young adults both as a recreational drug and for cognitive enhancing effects to improve their grades. MPD is known to act on the reward circuit; including the caudate nucleus (CN). The CN is comprised of medium spiny neurons containing largely dopamine (DA) D1 and D2 receptors. It has been widely shown that the DA system plays an important role in the response to MPD exposure. We investigated the role of both D1 and D2 DA receptors in the CN response to chronic MPD administration using specific D1 and D2 DA antagonist. Four groups of young adult, male SD rats were used: a saline (control) and three MPD dose groups (0.6, 2.5, and 10.0 mg/kg). The experiment lasted 11 consecutive days. Each MPD dose group was randomly divided into two subgroups to receive either a 0.4 mg/kg SCH-23390 selective D1 DA antagonist or a 0.3 mg/kg raclopride selective D2 DA antagonist prior to their final (repetitive) MPD rechallenge administration. It was observed that selective D1 DA antagonist (SCH-23390) given 30 min prior to the last MPD exposure at ED11 partially reduced or prevented the effect induced by MPD exposure in CN neuronal firing rates across all MPD doses. Selective D2 DA antagonist (raclopride) resulted in less obvious trends; some CN neuronal firing rates exhibited a slight increase in all MPD doses.


    National Aeronautics and Space Administration — Counting rate from the D2 detector in the Cosmic Ray System (CRS) electron telescope (TET) on Voyager 2 during the Uranus encounter. The D2 detector nominally...


    National Aeronautics and Space Administration — Counting rate from the D2 detector in the Cosmic Ray System (CRS) electron telescope (TET) on Voyager 2 during the Neptune encounter. The D2 detector nominally...

  9. High-accuracy mass determination of neutron-rich rubidium and strontiumiIsotopes

    CERN Document Server

    Raimbault-Hartmann, H; Beck, D; Bollen, G; De Saint-Simon, M; Kluge, H J; König, M; Moore, R B; Schwarz, S; Savard, G; Szerypo, J


    The penning-trap mass spectrometer ISOLTRAP, installed at the on-line isotope separator ISOLDE at CERN, has been used to measure atomic masses of $^{88,89,90m,91,92,93,94}$Rb and $^{91- 95}$Sr. Using a resolving power of R $\\!\\scriptstyle\\approx$1 million a mass accuracy of typically 10 keV was achieved for all nuclides. Discrepancies with older data are analyzed and discussed, leading to corrections to those data. Together with the present ISOLTRAP data these corrected data have been used in the general mass adjustment.

  10. Satisfactory surgical outcome of T2 gastric cancer after modified D2 lymphadenectomy. (United States)

    Zhang, Shupeng; Wu, Liangliang; Wang, Xiaona; Ding, Xuewei; Liang, Han


    Though D2 lymphadenectomy has been increasingly regarded as standard surgical procedure for advanced gastric cancer (GC), the modified D2 (D1 + 7, 8a and 9) lymphadenectomy may be more suitable than D2 dissection for T2 stage GC. The purpose of this study is to elucidate whether the surgical outcome of modified D2 lymphadenectomy was comparable to that of standard D2 dissection in T2 stage GC patients. A retrospective cohort study with 77 cases and 77 controls matched for baseline characteristics was conducted. Patients were categorized into two groups according to the extent of lymphadenectomy: the modified D2 group (mD2) and the standard D2 group (D2). Surgical outcome and recurrence date were compared between the two groups. The 5-year overall survival (OS) rate was 71.4% for patients accepted mD2 lymphadenectomy and 70.1% for those accepted standard D2, respectively, and the difference was not statistically significant. Multivariate survival analysis revealed that curability, tumor size, TNM stage and postoperative complications were independently prognostic factors for T2 stage GC patients. Patients in the mD2 group tended to have less intraoperative blood loss (P=0.001) and shorter operation time (PD2 group. While there were no significant differences in recurrence rate and types, especially lymph node recurrence, between the two groups. The surgical outcome of mD2 lymphadenectomy was equal to that of standard D2, and the use of mD2 instead of standard D2 can be a better option for T2 stage GC.

  11. VirD2 of Agrobacterium tumefaciens : functional domains and biotechnological applications

    NARCIS (Netherlands)

    Kregten, Maartje van


    Agrobacterium tumefaciens is a pathogenic bacterium, which can genetically transform plants and other organisms. It does so by translocating a part of its DNA, the T-strand, in complex with the relaxase protein VirD2. We have shown that VirD2 is the determinant of translocation of the VirD2-T-strand

  12. Aciduria D-2-hidroxiglutárica. Reporte de dos casos

    NARCIS (Netherlands)

    Mahfoud, Antionieta; Domínguez, Carmen Luisa; Rashed, Mohamed; Durán, Marinus; Rodríguez, Tania; Rodríguez, Daniel; Landa, Vanesa


    D-2-hydroxyglutaric aciduria (D-2-HGA) is a cerebral organic aciduria characterized by the accumulation of abnormal amounts of D-2-hydroxyglutaric acid in cerebrospinal fluid, blood, and urine. The clinical phenotype varies widely from neonatal severe epileptic encephalopathy to asymptomatic.

  13. Cabergoline, dopamine D2 receptor agonist, prevents neuronal cell death under oxidative stress via reducing excitotoxicity.

    Directory of Open Access Journals (Sweden)

    Haruki Odaka

    Full Text Available Several lines of evidence demonstrate that oxidative stress is involved in the pathogenesis of neurodegenerative diseases, including Parkinson's disease. Potent antioxidants may therefore be effective in the treatment of such diseases. Cabergoline, a dopamine D2 receptor agonist and antiparkinson drug, has been studied using several cell types including mesencephalic neurons, and is recognized as a potent radical scavenger. Here, we examined whether cabergoline exerts neuroprotective effects against oxidative stress through a receptor-mediated mechanism in cultured cortical neurons. We found that neuronal death induced by H₂O₂ exposure was inhibited by pretreatment with cabergoline, while this protective effect was eliminated in the presence of a dopamine D2 receptor inhibitor, spiperone. Activation of ERK1/2 by H₂O₂ was suppressed by cabergoline, and an ERK signaling pathway inhibitor, U0126, similarly protected cortical neurons from cell death. This suggested the ERK signaling pathway has a critical role in cabergoline-mediated neuroprotection. Furthermore, increased extracellular levels of glutamate induced by H₂O₂, which might contribute to ERK activation, were reduced by cabergoline, while inhibitors for NMDA receptor or L-type Ca²⁺ channel demonstrated a survival effect against H₂O₂. Interestingly, we found that cabergoline increased expression levels of glutamate transporters such as EAAC1. Taken together, these results suggest that cabergoline has a protective effect on cortical neurons via a receptor-mediated mechanism including repression of ERK1/2 activation and extracellular glutamate accumulation induced by H₂O₂.

  14. For Earth into space: The German Spacelab Mission D-2 (United States)

    Sahm, P. R.; Keller, M. H.; Schiewe, B.

    The Spacelab Mission D-2 successfully lifted off from Kennedy Space Center on April 26, 1993. With 88 experiments on board covering eleven different research disciplines it was a very ambitious mission. Besides materials and life science subjects, the mission also encompassed astronomy, earth observation, radiation physics and biology, telecommunication, automation and robotics. Notable results were obtained in almost all cases. To give some examples of the scientific output, building upon results obtained in previous missions (FSLP, D1) diffusion in melts was broadly represented delivering most precise data on the atomic mobility within various liquids, and crystal growth experiments (the largest gallium arsenide crystal grown by the floating zone technique, so far obtained anywhere, was one of the results), biological cell growth experiments were continued (for example, beer yeast cultures, continuing their growth on earth, delivered a qualitatively superior brewery result), the human physiology miniclinic configuration ANTHRORACK gave novel insights concerning cardiovascular, pulmonary, and renal (fluid volume determining) factors. Astronomical experiments yielded insights into our own galaxy within the ultra violet spectrum, earth observation experiments delivered the most precise resolution data superimposed by thematic mapping of many areas of the Earth, and the robotics experiment brought a remarkable feature in that a flying object was caught by the space robot, which was only achieved through several innovative advances during the time of experiment preparation. The eight years of preparation were also beneficial in another sense. Several discoveries have been made, and various technology transfers into ground-based processes were verified. To name the outstanding ones, in the materials science a novel bearing materials production process was developped, a patent granted for an improved high temperature heating chamber; with life sciences a new hormone

  15. Wavelength dispersion measurement of electro-optic coefficients in the range of 520 to 930 nm in rubidium titanyl phosphate using spectral interferometry. (United States)

    Gobert, Olivier; Fedorov, Nikita; Mennerat, Gabriel; Lupinski, Dominique; Guillaumet, Delphine; Perdrix, Michel; Bourgeade, Antoine; Comte, Michel


    Rubidium titanyl phosphate (RTP) is widely used for electro-optical applications at low switching voltages. RTP is nonhygroscopic and does not induce piezoelectric ringing up to the megahertz range. It has large electro-optic (EO) coefficients and a high damage threshold. We present here the EO coefficient wavelength dispersion measurements in the [550,950] nm spectral range using a method based on spectral interferometry. These data are necessary for, among other things, a quantitative modelization of an EO carrier-envelope phase shifter.

  16. Limitation on the accelerating gradient of a wakefield excited by an ultrarelativistic electron beam in rubidium plasma

    Directory of Open Access Journals (Sweden)

    N. Vafaei-Najafabadi


    Full Text Available We have investigated the viability of using plasmas formed by ionization of high Z, low ionization potential element rubidium (Rb for beam-driven plasma wakefield acceleration. The Rb vapor column confined by argon (Ar buffer gas was used to reduce the expected limitation on the beam propagation length due to head erosion that was observed previously when a lower Z but higher ionization potential lithium vapor was used. However, injection of electrons into the wakefield due to ionization of Ar buffer gas and nonuniform ionization of Rb^{1+} to Rb^{2+} was a possible concern. In this paper we describe experimental results and the supporting simulations which indicate that such ionization of Ar and Rb^{1+} in the presence of combined fields of the beam and the wakefield inside the wake does indeed occur. Some of this charge accumulates in the accelerating region of the wake leading to the reduction of the electric field—an effect known as beam loading. The beam-loading effect is quantified by determining the average transformer ratio ⟨R⟩ which is the maximum energy gained divided by the maximum energy lost by the electrons in the bunch used to produce the wake. ⟨R⟩ is shown to depend on the propagation length and the quantity of the accumulated charge, indicating that the distributed injection of secondary Rb electrons is the main cause of beam loading in this experiment. The average transformer ratio is reduced from 1.5 to less than 1 as the excess charge from secondary ionization increased from 100 to 700 pC. The simulations show that while the decelerating field remains constant, the accelerating field is reduced from its unloaded value of 82 to 46  GeV/m due to this distributed injection of dark current into the wake.

  17. High-connectivity networks and hybrid inorganic rod materials built from potassium and rubidium p-halide-substituted aryloxides. (United States)

    Morris, J Jacob; Noll, Bruce C; Henderson, Kenneth W


    A series of complex networks have been synthesized from the association of potassium and rubidium p-halide-substituted aryloxides using 1,4-dioxane molecules as neutral linkers. The crystalline polymers [(4-F-C6H4OK)6 x (dioxane)4]infinity (1), [(4-I-C6H4OK)6 x (dioxane)6]infinity (2), and [(4-I-C6H4ORb)6 x (dioxane)6]infinity (3) are built from discreet, hexameric M6O6 aggregates. Compound 1 forms an unusual 16-connected framework involving both K-F and K-O(diox) interactions. Each hexamer connects to eight neighboring aggregates through double-bridging contacts, resulting in a body-centered cubic (bcu) topology. Compounds 2 and 3 are isostructural, 12-connected networks, where each aggregate utilizes six dioxane double bridges to form primitive cubic (pcu) nets. In contrast, the complexes [(4-Cl-C6H4OK)3 x (dioxane)]infinity (4), [(4-Br-C6H4OK)2 x (dioxane)0.5]infinity (5), and [(4-Br-C6H4ORb)5 x (dioxane)5]infinity (6) are built from one-dimensional (1D) inorganic rods composed solely of M-O(Ar) interactions. The extended structures of both 4 and 5 can be described as pcu nets, where parallel 1D inorganic pillars are connected through dioxane bridges. Compound 6 is also composed of parallel 1D inorganic rods, but in this instance the coordinated dioxane molecules do not bridge, resulting in isolated, close-packed chains in the solid state.

  18. Effect of Rubidium Incorporation on the Structural, Electrical, and Photovoltaic Properties of Methylammonium Lead Iodide-Based Perovskite Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ik Jae [Department of Materials; Seo, Seongrok [Department of Energy; Park, Min Ah [Department of Materials; Lee, Sangwook [School of Materials Science and Engineering, Kyungpook National University, Daegu 41566, South Korea; Kim, Dong Hoe [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States; Zhu, Kai [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States; Shin, Hyunjung [Department of Energy; Kim, Jin Young [Department of Materials


    We report the electrical properties of rubidium-incorporated methylammonium lead iodide ((RbxMA1-x)PbI3) films and the photovoltaic performance of (RbxMA1-x)PbI3 film-based p-i-n-type perovskite solar cells (PSCs). The incorporation of a small amount of Rb+ (x = 0.05) increases both the open circuit voltage (Voc) and the short circuit photocurrent density (Jsc) of the PSCs, leading to an improved power conversion efficiency (PCE). However, a high fraction of Rb+ incorporation (x = 0.1 and 0.2) decreases the Jsc and thus the PCE, which is attributed to the phase segregation of the single tetragonal perovskite phase to a MA-rich tetragonal perovskite phase and a RbPbI3 orthorhombic phase at high Rb fractions. Conductive atomic force microscopic and admittance spectroscopic analyses reveal that the single-phase (Rb0.05MA0.95)PbI3 film has a high electrical conductivity because of a reduced deep-level trap density. We also found that Rb substitution enhances the diode characteristics of the PSC, as evidenced by the reduced reverse saturation current (J0). The optimized (RbxMA1-x)PbI3 PSCs exhibited a PCE of 18.8% with negligible hysteresis in the photocurrent-voltage curve. The results from this work enhance the understanding of the effect of Rb incorporation into organic-inorganic hybrid halide perovskites and enable the exploration of Rb-incorporated mixed perovskites for various applications, such as solar cells, photodetectors, and light-emitting diodes.

  19. Rubidium and zirconium abundances in massive Galactic asymptotic giant branch stars revisited (United States)

    Pérez-Mesa, V.; Zamora, O.; García-Hernández, D. A.; Plez, B.; Manchado, A.; Karakas, A. I.; Lugaro, M.


    Context. Luminous Galactic OH/IR stars have been identified as massive (>4-5 M⊙) asymptotic giant branch (AGB) stars experiencing hot bottom burning and Li production. Their Rb abundances and [Rb/Zr] ratios, as derived from classical hydrostatic model atmospheres, are significantly higher than predictions from AGB nucleosynthesis models, posing a problem for our understanding of AGB evolution and nucleosynthesis. Aims: We report new Rb and Zr abundances in the full sample (21) of massive Galactic AGB stars, previously studied with hydrostatic models, by using more realistic extended model atmospheres. Methods: For this, we use a modified version of the spectral synthesis code Turbospectrum and consider the presence of a circumstellar envelope and radial wind in the modelling of the optical spectra of these massive AGB stars. The Rb and Zr abundances are determined from the 7800 Å Rb I resonant line and the 6474 Å ZrO bandhead, respectively, and we explore the sensitivity of the derived abundances to variations of the stellar (Teff) and wind (Ṁ, β and vexp) parameters in the pseudo-dynamical models. The Rb and Zr abundances derived from the best spectral fits are compared with the most recent AGB nucleosynthesis theoretical predictions. Results: The Rb abundances derived with the pseudo-dynamical models are much lower (in the most extreme stars even by 1-2 dex) than those derived with the hydrostatic models, while the Zr abundances are similar. The Rb I line profile and Rb abundance are very sensitive to the wind mass-loss rate Ṁ (especially for Ṁ ≥ 10-8M⊙ yr-1) but much less sensitive to variations of the wind velocity-law (β parameter) and the expansion velocity vexp(OH). Conclusions: We confirm the earlier preliminary results based on a smaller sample of massive O-rich AGB stars, suggesting that the use of extended atmosphere models can solve the discrepancy between the AGB nucleosynthesis theoretical models and the observations of Galactic

  20. Hallucinogenic 5-HT2AR agonists LSD and DOI enhance dopamine D2R protomer recognition and signaling of D2-5-HT2A heteroreceptor complexes. (United States)

    Borroto-Escuela, Dasiel O; Romero-Fernandez, Wilber; Narvaez, Manuel; Oflijan, Julia; Agnati, Luigi F; Fuxe, Kjell


    Dopamine D2LR-serotonin 5-HT2AR heteromers were demonstrated in HEK293 cells after cotransfection of the two receptors and shown to have bidirectional receptor-receptor interactions. In the current study the existence of D2L-5-HT2A heteroreceptor complexes was demonstrated also in discrete regions of the ventral and dorsal striatum with in situ proximity ligation assays (PLA). The hallucinogenic 5-HT2AR agonists LSD and DOI but not the standard 5-HT2AR agonist TCB2 and 5-HT significantly increased the density of D2like antagonist (3)H-raclopride binding sites and significantly reduced the pKiH values of the high affinity D2R agonist binding sites in (3)H-raclopride/DA competition experiments. Similar results were obtained in HEK293 cells and in ventral striatum. The effects of the hallucinogenic 5-HT2AR agonists on D2R density and affinity were blocked by the 5-HT2A antagonist ketanserin. In a forskolin-induced CRE-luciferase reporter gene assay using cotransfected but not D2R singly transfected HEK293 cells DOI and LSD but not TCB2 significantly enhanced the D2LR agonist quinpirole induced inhibition of CRE-luciferase activity. Haloperidol blocked the effects of both quinpirole alone and the enhancing actions of DOI and LSD while ketanserin only blocked the enhancing actions of DOI and LSD. The mechanism for the allosteric enhancement of the D2R protomer recognition and signalling observed is likely mediated by a biased agonist action of the hallucinogenic 5-HT2AR agonists at the orthosteric site of the 5-HT2AR protomer. This mechanism may contribute to the psychotic actions of LSD and DOI and the D2-5-HT2A heteroreceptor complex may thus be a target for the psychotic actions of hallunicogenic 5-HT2A agonists. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Dopamine-induced apoptosis of lactotropes is mediated by the short isoform of D2 receptor.

    Directory of Open Access Journals (Sweden)

    Daniela Betiana Radl

    Full Text Available Dopamine, through D2 receptor (D2R, is the major regulator of lactotrope function in the anterior pituitary gland. Both D2R isoforms, long (D2L and short (D2S, are expressed in lactotropes. Although both isoforms can transduce dopamine signal, they differ in the mechanism that leads to cell response. The administration of D2R agonists, such as cabergoline, is the main pharmacological treatment for prolactinomas, but resistance to these drugs exists, which has been associated with alterations in D2R expression. We previously reported that dopamine and cabergoline induce apoptosis of lactotropes in primary culture in an estrogen-dependent manner. In this study we used an in vivo model to confirm the permissive action of estradiol in the apoptosis of anterior pituitary cells induced by D2R agonists. Administration of cabergoline to female rats induced apoptosis, measured by Annexin-V staining, in anterior pituitary gland from estradiol-treated rats but not from ovariectomized rats. To evaluate the participation of D2R isoforms in the apoptosis induced by dopamine we used lactotrope-derived PR1 cells stably transfected with expression vectors encoding D2L or D2S receptors. In the presence of estradiol, dopamine induced apoptosis, determined by ELISA and TUNEL assay, only in PR1-D2S cells. To study the role of p38 MAPK in apoptosis induced by D2R activation, anterior pituitary cells from primary culture or PR1-D2S were incubated with an inhibitor of the p38 MAPK pathway (SB203850. SB203580 blocked the apoptotic effect of D2R activation in lactotropes from primary cultures and PR1-D2S cells. Dopamine also induced p38 MAPK phosphorylation, determined by western blot, in PR1-D2S cells and estradiol enhanced this effect. These data suggest that, in the presence of estradiol, D2R agonists induce apoptosis of lactotropes by their interaction with D2S receptors and that p38 MAPK is involved in this process.

  2. The absorption spectrum of D2O in the region of 0.97 μm: the 3ν1 + ν3 vibrational-rotational band (United States)

    Serdyukov, V. I.; Sinitsa, L. N.


    The vibrational-rotational absorption spectrum of D2O in the range from 10 120 to 10 450 cm-1 is recorded on a Fourier transform spectrometer with a resolution of 0.05 cm-1. The measurements were performed using a multipass White cell with an optical path length of 24 m. A light-emitting diode with brightness higher than that of other devices was used as a radiation source. The signal-to-noise ratio was about 104. The spectrum is interpreted as consisting of lines of more than 400 transitions. The spectral characteristics of lines (centers, intensities, and half widths) are determined by fitting the Voigt profile parameters to experimental data by the least-squares method. The intensities of lines and the experimental rotational energy levels of the (301) vibrational state of the D2 16O molecule with high rotational quantum numbers are determined for the first time.

  3. Abnormal modulation of reward versus punishment learning by a dopamine D2-receptor antagonist in pathological gamblers. (United States)

    Janssen, Lieneke Katharina; Sescousse, Guillaume; Hashemi, Mahur Melina; Timmer, Monique Harmina Maria; ter Huurne, Niels Peter; Geurts, Dirk Everdina Maria; Cools, Roshan


    Pathological gambling has been associated with dopamine transmission abnormalities, in particular dopamine D2-receptor deficiency, and reversal learning deficits. Moreover, pervasive theoretical accounts suggest a key role for dopamine in reversal learning. However, there is no empirical evidence for a direct link between dopamine, reversal learning and pathological gambling. The aim of the present study is to triangulate dopamine, reversal learning, and pathological gambling. Here, we assess the hypothesis that pathological gambling is accompanied by dopamine-related problems with learning from reward and punishment by investigating effects of the dopamine D2-receptor antagonist sulpiride (400 mg) on reward- and punishment-based reversal learning in 18 pathological gamblers and 22 healthy controls, using a placebo-controlled, double-blind, counter-balanced design. In line with previous studies, blockade of D2 receptors with sulpiride impaired reward versus punishment reversal learning in controls. By contrast, sulpiride did not have any outcome-specific effects in gamblers. These data demonstrate that pathological gambling is associated with a dopamine-related anomaly in reversal learning from reward and punishment.

  4. Transient overexpression of striatal D2 receptors impairs operant motivation and interval timing. (United States)

    Drew, Michael R; Simpson, Eleanor H; Kellendonk, Christoph; Herzberg, William G; Lipatova, Olga; Fairhurst, Stephen; Kandel, Eric R; Malapani, Chara; Balsam, Peter D


    The striatum receives prominent dopaminergic innervation that is integral to appetitive learning, performance, and motivation. Signaling through the dopamine D2 receptor is critical for all of these processes. For instance, drugs with high affinity for the D2 receptor potently alter timing of operant responses and modulate motivation. Recently, in an attempt to model a genetic abnormality encountered in schizophrenia, mice were generated that reversibly overexpress D2 receptors specifically in the striatum (Kellendonk et al., 2006). These mice have impairments in working memory and behavioral flexibility, components of the cognitive symptoms of schizophrenia, that are not rescued when D2 overexpression is reversed in the adult. Here we report that overexpression of striatal D2 receptors also profoundly affects operant performance, a potential index of negative symptoms. Mice overexpressing D2 exhibited impairments in the ability to time food rewards in an operant interval timing task and reduced motivation to lever press for food reward in both the operant timing task and a progressive ratio schedule of reinforcement. The motivational deficit, but not the timing deficit, was rescued in adult mice by reversing D2 overexpression with doxycycline. These results suggest that early D2 overexpression alters the organization of interval timing circuits and confirms that striatal D2 signaling in the adult regulates motivational process. Moreover, overexpression of D2 under pathological conditions such as schizophrenia and Parkinson's disease could give rise to motivational and timing deficits.

  5. A randomized trial of high-dose vitamin D2 in relapsing-remitting multiple sclerosis. (United States)

    Stein, M S; Liu, Y; Gray, O M; Baker, J E; Kolbe, S C; Ditchfield, M R; Egan, G F; Mitchell, P J; Harrison, L C; Butzkueven, H; Kilpatrick, T J


    Higher latitude, lower ultraviolet exposure, and lower serum 25-hydroxyvitamin D (25OHD) correlate with higher multiple sclerosis (MS) prevalence, relapse rate, and mortality. We therefore evaluated the effects of high-dose vitamin D2 (D2) in MS. Adults with clinically active relapsing-remitting MS (RRMS) were randomized to 6 months' double-blind placebo-controlled high-dose vitamin D2, 6,000 IU capsules, dose adjusted empirically aiming for a serum 25OHD 130-175 nM. All received daily low-dose (1,000 IU) D2 to prevent deficiency. Brain MRIs were performed at baseline, 4, 5, and 6 months. Primary endpoints were the cumulative number of new gadolinium-enhancing lesions and change in the total volume of T2 lesions. Secondary endpoints were Expanded Disability Status Scale (EDSS) score and relapses. Twenty-three people were randomized, of whom 19 were on established interferon or glatiramer acetate (Copaxone) treatment. Median 25OHD rose from 54 to 69 nM (low-dose D2) vs 59 to 120 nM (high-dose D2) (p = 0.002). No significant treatment differences were detected in the primary MRI endpoints. Exit EDSS, after adjustment for entry EDSS, was higher following high-dose D2 than following low-dose D2 (p = 0.05). There were 4 relapses with high-dose D2 vs none with low-dose D2 (p = 0.04). We did not find a therapeutic advantage in RRMS for high-dose D2 over low-dose D2 supplementation. This study provides Class I evidence that high-dose vitamin D2 (targeting 25OHD 130-175 nM), compared to low-dose supplementation (1,000 IU/d), was not effective in reducing MRI lesions in patients with RRMS.

  6. Terahertz Spectroscopy of the Bending Vibrations of Acetylene 12C2H2 and 12C2D2 (United States)

    Yu, Shanshan; Drouin, B.; Pearson, J.


    Several fundamental interstellar molecules, e.g., C2H2, CH4 and C3, are completely symmetric molecules and feature no permanent dipole moment and no pure rotation spectrum. As a result they have only previously been observed in the infrared. However, directly observing them with the rest of the molecular column especially when the source is spatially resolved would be very valuable in understanding chemical evolution. Vibrational difference bands provide a means to detect symmetric molecules with microwave precision using terahertz techniques. Herschel, SOFIA and ALMA have the potential to identify a number of vibrational difference bands of light symmetric species. This paper reports laboratory results on 12C2H2 and 12C2D2. Symmetric acetylene isotopologues have two bending modes, the trans bending and the cis bending. Their difference bands are allowed and occur in the microwave, terahertz, and far-infrared wavelengths, with band origins at 3500 GHz for 12C2H2 and 900 GHz for 12C2D2. Twenty 12C2H2 P branch high-J transitions and two hundred and fifty-one 12C2D2 P Q and R branch transitions have been measured in the 0.2 - 1.6 THz region with precision of 50 to 100 kHz. These lines were modeled together with prior data on the pure bending levels. Significantly improved molecular parameters were obtained for 12C2H2 and 12C2D2 with the combined data set, and new frequency and intensity predictions were made to support astrophysics applications. The research was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. S. Y. was supported by an appointment to the NASA Postdoctoral Program, administrated by Oak Ridge Associated Universities through a contract with NASA.


    Directory of Open Access Journals (Sweden)

    Paula Fernanda da Silva Farina


    Full Text Available The effects of cryogenic treatments on an AISI D2 cold work tool steel using X-ray diffraction from syncronton radiation are studied. The aim of this work is to verify the effects of: i time at cryogenic temperatures (3, 10 and 30 hours; ii cryogenic temperatures (–80°C and –196°C; iii stress relief heat treatment (130°C before cryogenic treatments; iv effect of double tempering at 520°C for 2 hours each time, after cryogenic treatment at –196°C for 30 hours, with and without previous stress relief. X-ray diffraction experiments were conducted at the line D10B-XPD of the Laboratório Nacional de Luz Síncrotron and the experimental results were treated using Rietveld refining, with TOPAS Academic in conjunction with cards from the ICCD-PDF 2006 database for austenite, martensite and carbides M7C3and M2C. Tempered samples were characterized using SEM and SEM-FEG. Volume fraction of retained austenite and carbides, as well as changes in the crystal lattices of martensite and austenite are obtained from the X-ray experiments.

  8. Multiple D2 heteroreceptor complexes: new targets for treatment of schizophrenia (United States)

    Borroto-Escuela, Dasiel O.; Pintsuk, Julia; Schäfer, Thorsten; Friedland, Kristina; Ferraro, Luca; Tanganelli, Sergio; Liu, Fang; Fuxe, Kjell


    The dopamine (DA) neuron system most relevant for schizophrenia is the meso-limbic-cortical DA system inter alia densely innervating subcortical limbic regions. The field of dopamine D2 receptors and schizophrenia changed markedly with the discovery of many types of D2 heteroreceptor complexes in subcortical limbic areas as well as the dorsal striatum. The results indicate that the D2 is a hub receptor which interacts not only with many other G protein-coupled receptors (GPCRs) including DA isoreceptors but also with ion-channel receptors, receptor tyrosine kinases, scaffolding proteins and DA transporters. Disturbances in several of these D2 heteroreceptor complexes may contribute to the development of schizophrenia through changes in the balance of diverse D2 homo- and heteroreceptor complexes mediating the DA signal, especially to the ventral striato-pallidal γ-aminobutyric acid (GABA) pathway. This will have consequences for the control of this pathway of the glutamate drive to the prefrontal cortex via the mediodorsal thalamic nucleus which can contribute to psychotic processes. Agonist activation of the A2A protomer in the A2A–D2 heteroreceptor complex inhibits D2 Gi/o mediated signaling but increases the D2 β-arrestin2 mediated signaling. Through this allosteric receptor–receptor interaction, the A2A agonist becomes a biased inhibitory modulator of the Gi/o mediated D2 signaling, which may the main mechanism for its atypical antipsychotic properties especially linked to the limbic A2A–D2 heterocomplexes. The DA and glutamate hypotheses of schizophrenia come together in the signal integration in D2–N-methyl-d-aspartate (NMDA) and A2A–D2–metabotropic glutamate receptor 5 (mGlu5) heteroreceptor complexes, especially in the ventral striatum. 5-Hydroxytryptamine 2A (5-HT2A)–D2 heteroreceptor complexes are special targets for atypical antipsychotics with high potency to block their 5-HT2A protomer signaling in view of the potential development of

  9. Activation of D2 dopamine receptor-expressing neurons in the nucleus accumbens increases motivation (United States)

    Soares-Cunha, Carina; Coimbra, Barbara; David-Pereira, Ana; Borges, Sonia; Pinto, Luisa; Costa, Patricio; Sousa, Nuno; Rodrigues, Ana J.


    Striatal dopamine receptor D1-expressing neurons have been classically associated with positive reinforcement and reward, whereas D2 neurons are associated with negative reinforcement and aversion. Here we demonstrate that the pattern of activation of D1 and D2 neurons in the nucleus accumbens (NAc) predicts motivational drive, and that optogenetic activation of either neuronal population enhances motivation in mice. Using a different approach in rats, we further show that activating NAc D2 neurons increases cue-induced motivational drive in control animals and in a model that presents anhedonia and motivational deficits; conversely, optogenetic inhibition of D2 neurons decreases motivation. Our results suggest that the classic view of D1–D2 functional antagonism does not hold true for all dimensions of reward-related behaviours, and that D2 neurons may play a more prominent pro-motivation role than originally anticipated. PMID:27337658

  10. Adsorbed carbon nanomaterials for surface and interface-engineered stable rubidium multi-cation perovskite solar cells. (United States)

    Mahmud, Md Arafat; Elumalai, Naveen Kumar; Upama, Mushfika Baishakhi; Wang, Dian; Zarei, Leila; Gonçales, Vinicius R; Wright, Matthew; Xu, Cheng; Haque, Faiazul; Uddin, Ashraf


    The current work reports the simultaneous enhancement in efficiency and stability of low-temperature, solution-processed triple cation based MA 0.57 FA 0.38 Rb 0.05 PbI 3 (MA: methyl ammonium, FA: formamidinium, Rb: rubidium) perovskite solar cells (PSCs) by means of adsorbed carbon nanomaterials at the perovskite/electron transporting layer interface. The quantity and quality of the adsorbents are precisely controlled to electronically modify the ETL surface and lower the energy barrier across the interface. Carbon derivatives namely fullerene (C 60 ) and PC 71 BM ([6,6]-phenyl C71 butyric acid methyl ester) are employed as adsorbents in conjunction with ZnO and together serve as a bilayer electron transporting layer (ETL). The adsorbed fullerene (C 60 -ZnO, abbreviated as C-ZnO) passivates the interstitial trap-sites of ZnO with interstitial intercalation of oxygen atoms in the ZnO lattice structure. C-ZnO ETL based PSCs demonstrate about a 19% higher average PCE compared to conventional ZnO ETL based devices and a nearly 9% higher average PCE than PC 71 BM adsorbed-ZnO (P-ZnO) ETL based PSCs. In addition, the interstitial trap-state passivation with a C-ZnO film upshifts the Fermi-level position of the C-ZnO ETL by 130 meV, with reference to the ZnO ETL, which contributes to an enhanced n-type conductivity. The photocurrent hysteresis phenomenon in C-ZnO PSCs is also substantially reduced due to mitigated charge trapping phenomena and concomitant reduction in an electrode polarization process. Another major highlight of this work is that, C-ZnO PSCs demonstrate a superior device stability retaining about 94% of its initial PCE in the course of a month-long, systematic degradation study conducted in our work. The enhanced device stability with C-ZnO PSCs is attributed to their high resistance to aging-induced recombination phenomena and a water-induced perovskite degradation process, due to a lower content of oxygen-related chemisorbed species on the C-ZnO ETL

  11. Myocardial blood flow assessment with {sup 82}rubidium-PET imaging in patients with left bundle branch block

    Energy Technology Data Exchange (ETDEWEB)

    Falcao, Andrea; Chalela, William; Giorgi, Maria Clementina; Imada, Rodrigo; Soares Junior, Jose; Do Val, Renata; Oliveira, Marco Antonio; Izaki, Marisa; Kalil Filho, Roberto; Meneghetti, Jose C., E-mail: [Universidade de Sao Paulo (InCor/USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Instituto do Coracao


    Objectives: Perfusion abnormalities are frequently seen in Single Photon Emission Computed Tomography (SPECT) when a left bundle branch block is present. A few studies have shown decreased coronary flow reserve in the left anterior descending territory, regardless of the presence of coronary artery disease. Objective: we sought to investigate rubidium-82 ({sup 82}Rb) positron emission tomography imaging in the assessment of myocardial blood flow and coronary flow reserve in patients with left bundle branch block. Methods: thirty-eight patients with left bundle branch block (GI), median age 63.5 years, 22 (58%) female, 12 with coronary artery disease (≥70%; GI-A) and 26 with no evidence of significant coronary artery disease (GI-B), underwent rest-dipyridamole stress {sup 82}Rb-positron emission tomography with absolute quantitative flow measurements using Cedars-Sinai software (mL/min/g). The relative myocardial perfusion and left ventricular ejection fraction were assessed in 17 segments. These parameters were compared with those obtained from 30 patients with normal {sup 82}Rb-positron emission tomography studies and without left bundle branch block (GII). Results: stress myocardial blood flow and coronary flow reserve were significantly lower in GI than in GII (p>0.05). The comparison of coronary flow reserve between GI-A and GI-B showed that it was different from the global coronary flow reserve (p<0.05) and the stress flow was significantly lower in the anterior than in the septal wall for both groups. Perfusion abnormalities were more prevalent in GI-A (p=0.06) and the left ventricular ejection fraction was not different between GI-A and GI-B, whereas it was lower in GI than in GII (p<0.001). Conclusion: the data confirm that patients with left bundle branch block had decreased myocardial blood flow and coronary flow reserve and coronary flow reserve assessed by {sup 82}Rb-positron emission tomography imaging may be useful in identifying coronary artery

  12. Resolvin RvD2 reduces hypothalamic inflammation and rescues mice from diet-induced obesity. (United States)

    Pascoal, Livia B; Bombassaro, Bruna; Ramalho, Albina F; Coope, Andressa; Moura, Rodrigo F; Correa-da-Silva, Felipe; Ignacio-Souza, Leticia; Razolli, Daniela; de Oliveira, Diogo; Catharino, Rodrigo; Velloso, Licio A


    Diet-induced hypothalamic inflammation is an important mechanism leading to dysfunction of neurons involved in controlling body mass. Studies have shown that polyunsaturated fats can reduce hypothalamic inflammation. Here, we evaluated the presence and function of RvD2, a resolvin produced from docosahexaenoic acid, in the hypothalamus of mice. Male Swiss mice were fed either chow or a high-fat diet. RvD2 receptor and synthetic enzymes were evaluated by real-time PCR and immunofluorescence. RvD2 was determined by mass spectrometry. Dietary and pharmacological approaches were used to modulate the RvD2 system in the hypothalamus, and metabolic phenotype consequences were determined. All enzymes involved in the synthesis of RvD2 were detected in the hypothalamus and were modulated in response to the consumption of dietary saturated fats, leading to a reduction of hypothalamic RvD2. GPR18, the receptor for RvD2, which was detected in POMC and NPY neurons, was also modulated by dietary fats. The substitution of saturated by polyunsaturated fats in the diet resulted in increased hypothalamic RvD2, which was accompanied by reduced body mass and improved glucose tolerance. The intracerebroventricular treatment with docosahexaenoic acid resulted in increased expression of the RvD2 synthetic enzymes, increased expression of anti-inflammatory cytokines and improved metabolic phenotype. Finally, intracerebroventricular treatment with RvD2 resulted in reduced adiposity, improved glucose tolerance and increased hypothalamic expression of anti-inflammatory cytokines. Thus, RvD2 is produced in the hypothalamus, and its receptor and synthetic enzymes are modulated by dietary fats. The improved metabolic outcomes of RvD2 make this substance an attractive approach to treat obesity.

  13. Cytogenetic toxicity of D2O in human lymphocyte cultures. Increased sensitivity in Fanconi's anemia. (United States)

    Joenje, H; Oostra, A B; Wanamarta, A H


    Chromosomal aberrations were scored in lymphocyte cultures from healthy individuals, patients with Bloom syndrome, and patients with Fanconi's anemia, after 4-5 h exposure to culture medium containing 90% heavy water (D2O). D2O treatment resulted in occasional pulverization of metaphases, and increased frequencies of chromosomal breakage. Patients with Fanconi's anemia were particularly sensitive to the chromosome breaking effect of D2O.

  14. The Implementation of C-ID, R2D2 Model on Learning Reading Comprehension (United States)

    Rayanto, Yudi Hari; Rusmawan, Putu Ngurah


    The purposes of this research are to find out, (1) whether C-ID, R2D2 model is effective to be implemented on learning Reading comprehension, (2) college students' activity during the implementation of C-ID, R2D2 model on learning Reading comprehension, and 3) college students' learning achievement during the implementation of C-ID, R2D2 model on…

  15. Promoter de-methylation of cyclin D2 by sulforaphane in prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Hsu Anna


    Full Text Available Abstract Sulforaphane (SFN, an isothiocyanate derived from cruciferous vegetables, induces potent anti-proliferative effects in prostate cancer cells. One mechanism that may contribute to the anti-proliferative effects of SFN is the modulation of epigenetic marks, such as inhibition of histone deacetylase (HDAC enzymes. However, the effects of SFN on other common epigenetic marks such as DNA methylation are understudied. Promoter hyper-methylation of cyclin D2, a major regulator of cell cycle, is correlated with prostate cancer progression, and restoration of cyclin D2 expression exerts anti-proliferative effects on LnCap prostate cancer cells. Our study aimed to investigate the effects of SFN on DNA methylation status of cyclin D2 promoter, and how alteration in promoter methylation impacts cyclin D2 gene expression in LnCap cells. We found that SFN significantly decreased the expression of DNA methyltransferases (DNMTs, especially DNMT1 and DNMT3b. Furthermore, SFN significantly decreased methylation in cyclin D2 promoter regions containing c-Myc and multiple Sp1 binding sites. Reduced methlyation of cyclin D2 promoter corresponded to an increase in cyclin D2 transcript levels, suggesting that SFN may de-repress methylation-silenced cyclin D2 by impacting epigenetic pathways. Our results demonstrated the ability of SFN to epigenetically modulate cyclin D2 expression, and provide novel insights into the mechanisms by which SFN may regulate gene expression as a prostate cancer chemopreventive agent.

  16. Cerebral decortication reverses the effect of amphetamine on striatal D2 dopamine binding site density. (United States)

    Robertson, H A


    Unilateral ablation of the cerebral cortex produces a decrease of approximately 38% in striatal D2 dopamine binding site density. Chronic d-amphetamine treatment also produces a decrease of about 22% in D2 binding site density. Paradoxically, when rats were hemidecorticated and treated chronically with d-amphetamine, the density of striatal D2 dopamine binding sites on the decorticated side was increased (by about 50%) rather than decreased. Evidently d-amphetamine-induced down-regulation of D2 dopamine binding sites depends on an intact corticostriatal pathway.

  17. Prodifferentiation Activity of Novel Vitamin D2 Analogs PRI-1916 and PRI-1917 and Their Combinations with a Plant Polyphenol in Acute Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Matan Nachliely


    Full Text Available 1α,25-dihydroxyvitamin D3 (1,25D3 is a powerful differentiation inducer for acute myeloid leukemia (AML cells. However, 1,25D3 doses required for differentiation of AML cells may cause lethal hypercalcemia in vivo. There is evidence that vitamin D2 is less toxic than vitamin D3 in animals. Here, we determined the differentiation effects of novel analogs of 1α,25-dihydroxyvitamin D2 (1,25D2, PRI-1916 and PRI-1917, in which the extended side chains of their previously reported precursors (PRI-1906 and PRI-1907, respectively underwent further 24Z (24-cis modification. Using four human AML cell lines representing different stages of myeloid maturation (KG-1a, HL60, U937, and MOLM-13, we found that the potency of PRI-1916 was slightly higher or equal to that of PRI-1906 while PRI-1917 was significantly less potent than PRI-1907. We also demonstrated that 1,25D2 was a less effective differentiation agent than 1,25D3 in these cell lines. Irrespective of their differentiation potency, all the vitamin D2 derivatives tested were less potent than 1,25D3 in transactivating the DR3-type vitamin D response elements. However, similar to 1,25D3, both 1,25D2 and its analogs could strongly cooperate with the plant polyphenol carnosic acid in inducing cell differentiation and inhibition of G1–S cell cycle transition. These results indicate that the 24Z modification has contrasting effects on the differentiation ability of PRI-1906 and PRI-1907 and that the addition of a plant polyphenol could result in a similar extent of cell differentiation induced by different vitamin D compounds. The enhanced antileukemic effects of the tested combinations may constitute the basis for the development of novel approaches for differentiation therapy of AML.

  18. Loss of Plasticity in the D2-Accumbens Pallidal Pathway Promotes Cocaine Seeking. (United States)

    Heinsbroek, Jasper A; Neuhofer, Daniela N; Griffin, William C; Siegel, Griffin S; Bobadilla, Ana-Clara; Kupchik, Yonatan M; Kalivas, Peter W


    Distinct populations of D1- and D2-dopamine receptor-expressing medium spiny neurons (D1-/D2-MSNs) comprise the nucleus accumbens, and activity in D1-MSNs promotes, whereas activity in D2-MSNs inhibits, motivated behaviors. We used chemogenetics to extend D1-/D2-MSN cell specific regulation to cue-reinstated cocaine seeking in a mouse model of self-administration and relapse, and found that either increasing activity in D1-MSNs or decreasing activity in D2-MSNs augmented cue-induced reinstatement. Both D1- and D2-MSNs provide substantial GABAergic innervation to the ventral pallidum, and chemogenetic inhibition of ventral pallidal neurons blocked the augmented reinstatement elicited by chemogenetic regulation of either D1- or D2-MSNs. Because D1- and D2-MSNs innervate overlapping populations of ventral pallidal neurons, we next used optogenetics to examine whether changes in synaptic plasticity in D1- versus D2-MSN GABAergic synapses in the ventral pallidum could explain the differential regulation of VP activity. In mice trained to self-administer cocaine, GABAergic LTD was abolished in D2-, but not in D1-MSN synapses. A μ opioid receptor antagonist restored GABA currents in D2-, but not D1-MSN synapses of cocaine-trained mice, indicating that increased enkephalin tone on presynaptic μ opioid receptors was responsible for occluding the LTD. These results identify a behavioral function for D1-MSN innervation of the ventral pallidum, and suggest that losing LTDGABA in D2-MSN, but not D1-MSN input to ventral pallidum may promote cue-induced reinstatement of cocaine-seeking. More than 90% of ventral striatum is composed of two cell types, those expressing dopamine D1 or D2 receptors, which exert opposing roles on motivated behavior. Both cell types send GABAergic projections to the ventral pallidum and were found to differentially promote cue-induced reinstatement of cocaine seeking via the ventral pallidum. Furthermore, after cocaine self-administration, synaptic

  19. Genetically determined measures of striatal D2 signaling predict prefrontal activity during working memory performance.

    Directory of Open Access Journals (Sweden)

    Alessandro Bertolino


    Full Text Available Variation of the gene coding for D2 receptors (DRD2 has been associated with risk for schizophrenia and with working memory deficits. A functional intronic SNP (rs1076560 predicts relative expression of the two D2 receptors isoforms, D2S (mainly pre-synaptic and D2L (mainly post-synaptic. However, the effect of functional genetic variation of DRD2 on striatal dopamine D2 signaling and on its correlation with prefrontal activity during working memory in humans is not known.Thirty-seven healthy subjects were genotyped for rs1076560 (G>T and underwent SPECT with [123I]IBZM (which binds primarily to post-synaptic D2 receptors and with [123I]FP-CIT (which binds to pre-synaptic dopamine transporters, whose activity and density is also regulated by pre-synaptic D2 receptors, as well as BOLD fMRI during N-Back working memory.Subjects carrying the T allele (previously associated with reduced D2S expression had striatal reductions of [123I]IBZM and of [123I]FP-CIT binding. DRD2 genotype also differentially predicted the correlation between striatal dopamine D2 signaling (as identified with factor analysis of the two radiotracers and activity of the prefrontal cortex during working memory as measured with BOLD fMRI, which was positive in GG subjects and negative in GT.Our results demonstrate that this functional SNP within DRD2 predicts striatal binding of the two radiotracers to dopamine transporters and D2 receptors as well as the correlation between striatal D2 signaling with prefrontal cortex activity during performance of a working memory task. These data are consistent with the possibility that the balance of excitatory/inhibitory modulation of striatal neurons may also affect striatal outputs in relationship with prefrontal activity during working memory performance within the cortico-striatal-thalamic-cortical pathway.

  20. Receptor, Ligand and Transducer Contributions to Dopamine D2 Receptor Functional Selectivity.

    Directory of Open Access Journals (Sweden)

    Sean M Peterson

    Full Text Available Functional selectivity (or biased agonism is a property exhibited by some G protein-coupled receptor (GPCR ligands, which results in the modulation of a subset of a receptor's signaling capabilities and more precise control over complex biological processes. The dopamine D2 receptor (D2R exhibits pleiotropic responses to the biogenic amine dopamine (DA to mediate complex central nervous system functions through activation of G proteins and β-arrestins. D2R is a prominent therapeutic target for psychological and neurological disorders in which DA biology is dysregulated and targeting D2R with functionally selective drugs could provide a means by which pharmacotherapies could be developed. However, factors that determine GPCR functional selectivity in vivo may be multiple with receptors, ligands and transducers contributing to the process. We have recently described a mutagenesis approach to engineer biased D2R mutants in which G protein-dependent ([Gprot]D2R and β-arrestin-dependent signaling ([βarr]D2R were successfully separated (Peterson, et al. PNAS, 2015. Here, permutations of these mutants were used to identify critical determinants of the D2R signaling complex that impart signaling bias in response to the natural or synthetic ligands. Critical residues identified in generating [Gprot]D2R and [βarr]D2R conferred control of partial agonism at G protein and/or β-arrestin activity. Another set of mutations that result in G protein bias was identified that demonstrated that full agonists can impart unique activation patterns, and provided further credence to the concept of ligand texture. Finally, the contributions and interplay between different transducers indicated that G proteins are not aberrantly activated, and that receptor kinase and β-arrestin activities are inextricably linked. These data provide a thorough elucidation of the feasibility and malleability of D2R functional selectivity and point to means by which novel in vivo

  1. Hypoparathyroidism: Less Severe Hypocalcemia With Treatment With Vitamin D2 Compared With Calcitriol. (United States)

    Streeten, Elizabeth A; Mohtasebi, Yasaman; Konig, Manige; Davidoff, Lisa; Ryan, Kathleen


    Options for chronic treatment of hypoparathyroidism include calcitriol, recombinant human parathyroid hormone, and high-dose vitamin D (D2). D2 is used in a minority of patients because of fear of prolonged hypercalcemia and renal toxicity. There is a paucity of recent data about D2 use in hypoparathyroidism. Compare renal function, hypercalcemia, and hypocalcemia in patients with hypoparathyroidism treated chronically with either D2 (D2 group) or calcitriol. A retrospective study of patients with hypoparathyroidism treated at the University of Maryland Hospital. Participants were identified by a billing record search with diagnosis confirmed by chart review. Thirty patients were identified; 16 were treated chronically with D2, 14 with calcitriol. Data were extracted from medical records. Serum creatinine and calcium, hospitalizations, and emergency department (ED) visits for hypercalcemia and hypocalcemia. D2 and calcitriol groups were similar in age (58.9 ± 16.7 vs 50.9 ± 22.6 years, P = 0.28), sex, and treatment duration (17.8 ± 14.2 vs 8.5 ± 4.4 years, P = 0.076). Hospitalization or ED visits for hypocalcemia occurred in none of the D2 group vs four of 14 in the calcitriol group (P = 0.03); three in the calcitriol group had multiple ED visits. There were no differences between D2 and calcitriol groups in hospitalizations or ED visits for hypercalcemia, serum creatinine or calcium, or kidney stones. We found less morbidity from hypocalcemia in hypoparathyroid patients treated chronically with D2 compared with calcitriol and found no difference in renal function or morbidity from hypercalcemia. Treatment with D2 should be considered in patients with hypoparathyroidism, particularly in those who experience recurrent hypocalcemia.

  2. Dopamine D2 Receptors Regulate Collateral Inhibition between Striatal Medium Spiny Neurons (United States)

    van der Goes, Marie-Sophie; Partridge, John G.; Vicini, Stefano


    The principle neurons of the striatum are GABAergic medium spiny neurons (MSNs), whose collateral synapses onto neighboring neurons play critical roles in striatal function. MSNs can be divided by dopamine receptor expression into D1-class and D2-class MSNs, and alterations in D2 MSNs are associated with various pathological states. Despite overwhelming evidence for D2 receptors (D2Rs) in maintaining proper striatal function, it remains unclear how MSN collaterals are specifically altered by D2R activation. Here, we report that chronic D2R stimulation regulates MSN collaterals in vitro by presynaptic and postsynaptic mechanisms. We used corticostriatal cultures from mice in which MSN subtypes were distinguished by fluorophore expression. Quinpirole, an agonist for D2/3 receptors, was used to chronically activate D2Rs. Quinpirole increased the rate and strength of collateral formation onto D2R-containing MSNs as measured by dual whole-cell patch-clamp recordings. Additionally, these neurons were more sensitive to low concentrations of GABA and exhibited an increase in gephyrin puncta density, suggesting increased postsynaptic GABAA receptors. Last, quinpirole treatment increased presynaptic GABA release sites, as shown by increased frequency of sIPSCs and mIPSCs, correlating with increased VGAT (vesicular GABA transporter) puncta. Combined with the observation that there were no detectable differences in sensitivity to specific GABAA receptor modulators, we provide evidence that D2R activation powerfully transforms MSN collaterals via coordinated presynaptic and postsynaptic alterations. As the D2 class of MSNs is highly implicated in Parkinson's disease and other neurological disorders, our findings may contribute to understanding and treating the changes that occur in these pathological states. PMID:23986243

  3. Stability of globular proteins in H2O and D2O

    NARCIS (Netherlands)

    Efimova, Y. M.; Haemers, S.; Wierczinski, B.; Norde, W.; van Well, A. A.


    In several experimental techniques D2O rather then H2O is often used as a solvent for proteins. Concerning the influence of the solvent on the stability of the proteins, contradicting results have been reported in literature. In this paper the influence of H2O-D2O solvent substitution on the

  4. Stability of globular proteins in H2O and in D2O

    NARCIS (Netherlands)

    Efimova, Y.M.; Haemers, S.; Wierczinsky, B.; Norde, W.; Well, van A.A.


    In several experimental techniques D2O rather then H2O is often used as a solvent for proteins. Concerning the influence of the solvent on the stability of the proteins, contradicting results have been reported in literature. In this paper the influence of H2O-D2O solvent substitution on the

  5. D2.2.2 Final Version of the LinkedUp Evaluation Framework

    NARCIS (Netherlands)

    Drachsler, Hendrik; Stoyanov, Slavi; Guy, Marieke; Scheffel, Maren


    This document (D2.2.2) describes the LinkedUp consortium’s experience in developing and on- going improvement of the LinkedUp Evaluation Framework throughout three web open educational data competitions: Veni, Vidi, Vici. D2.2.2 is the final report regarding the Evaluation Framework (EF). It

  6. D2.3.3 Evaluation results of the LinkedUp VICI competition

    NARCIS (Netherlands)

    Drachsler, Hendrik


    This document D2.3.3 is the final report of Task 2.4 – Evaluation of challenge submissions. Task 2.4 is about the actual assessment of the participating projects within the LinkedUp Veni, Vidi and Vici competition on the basis of the LinkedUp Evaluation Framework (D2.2.1). The main objective of

  7. D2.3.2 Evaluation results of the LinkedUp VIDI competition

    NARCIS (Netherlands)

    Drachsler, Hendrik; Stoyanov, Slavi; Herder, Eelco; Marieke, Guy; Maren, Scheffel


    This document D2.3.2 is the second report of Task 2.4 - Evaluation of challenge submissions. Task 2.4 is about the actual assessment of the participating projects within the LinkedUp Veni, Vidi and Vici competition on the basis of the LinkedUp Evaluation Framework (D2.2.1). The main objective of

  8. 26 CFR 301.6104(d)-2 - Making applications and returns widely available. (United States)


    ... available. 301.6104(d)-2 Section 301.6104(d)-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) PROCEDURE AND ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns... having the document posted, as part of a database of similar documents of other tax-exempt organizations...

  9. Functional coupling between heterologously expressed dopamine D(2) receptors and KCNQ channels

    DEFF Research Database (Denmark)

    Ljungstrom, Trine; Grunnet, Morten; Jensen, Bo Skaaning


    Activation of KCNQ potassium channels by stimulation of co-expressed dopamine D(2) receptors was studied electrophysiologically in Xenopus laevis oocytes and in mammalian cells. To address the specificity of the interaction between D(2)-like receptors and KCNQ channels, combinations of KCNQ1...

  10. Varenicline increases striatal dopamine D(2/3) receptor binding in rats

    NARCIS (Netherlands)

    Crunelle, Cleo L.; Miller, Michelle L.; de Bruin, Kora; van den Brink, Wim; Booij, Jan


    Increasing dopamine D(2/3) receptor availability is postulated to be a treatment for drug addiction. Varenicline, an alpha4beta2-nicotinic partial agonist, is effective for nicotine dependence. We hypothesize that varenicline increases dopamine D(2/3) receptor availability. Twenty male drug-naïve

  11. Reducing Ventral Tegmental Dopamine D2 Receptor Expression Selectively Boosts Incentive Motivation

    NARCIS (Netherlands)

    de Jong, Johannes W.; Roelofs, Theresia J M; Mol, Frédérique M U; Hillen, Anne E J; Meijboom, Katharina E.; Luijendijk, Mieneke C M; Van Der Eerden, Harrie A M; Garner, Keith M.; Vanderschuren, Louk J M J; Adan, Roger A H


    Altered mesolimbic dopamine signaling has been widely implicated in addictive behavior. For the most part, this work has focused on dopamine within the striatum, but there is emerging evidence for a role of the auto-inhibitory, somatodendritic dopamine D2 receptor (D2R) in the ventral tegmental area

  12. Dopamine D2 receptor occupancy by olanzapine or risperidone in young patients with schizophrenia

    NARCIS (Netherlands)

    Lavalaye, J.; Linszen, D. H.; Booij, J.; Reneman, L.; Gersons, B. P.; van Royen, E. A.


    A crucial characteristic of antipsychotic medication is the occupancy of the dopamine (DA) D2 receptor. We assessed striatal DA D2 receptor occupancy by olanzapine and risperidone in 36 young patients [31 males, 5 females; mean age 21.1 years (16-28)] with first episode schizophrenia, using

  13. Striatal dopamine D2/3 receptor availability in treatment resistant depression.

    Directory of Open Access Journals (Sweden)

    Bart P de Kwaasteniet

    Full Text Available Several studies demonstrated improvement of depressive symptoms in treatment resistant depression (TRD after administering dopamine agonists which suggest abnormal dopaminergic neurotransmission in TRD. However, the role of dopaminergic signaling through measurement of striatal dopamine D(2/3 receptor (D2/3R binding has not been investigated in TRD subjects. We used [(123I]IBZM single photon emission computed tomography (SPECT to investigate striatal D2/3R binding in TRD. We included 6 severe TRD patients, 11 severe TRD patients on antipsychotics (TRD AP group and 15 matched healthy controls. Results showed no significant difference (p = 0.75 in striatal D2/3R availability was found between TRD patients and healthy controls. In the TRD AP group D2/3R availability was significantly decreased (reflecting occupancy of D2/3Rs by antipsychotics relative to TRD patients and healthy controls (p<0.001 but there were no differences in clinical symptoms between TRD AP and TRD patients. This preliminary study therefore does not provide evidence for large differences in D2/3 availability in severe TRD patients and suggests this TRD subgroup is not characterized by altered dopaminergic transmission. Atypical antipsychotics appear to have no clinical benefit in severe TRD patients who remain depressed, despite their strong occupancy of D2/3Rs.

  14. Modulatory Effects of Dopamine D2 Receptors on Spreading Depression in Rat Somatosensory Neocortex

    Directory of Open Access Journals (Sweden)

    Anna Maria Haarmann


    Full Text Available Introduction: Spreading depression (SD is a propagating wave of depolarization followed by depression of the neuroglial activities and can modulate extracellular dopamine concentrations in the neocortex. It has been shown that the dopaminergic system plays a role in migraine. SD has been suggested as a critical phenomenon in the pathophysiology of migraine. The aim of this study was to investigate the effect of dopamine D2 receptors on the characteristic features of SD in rat neocortical tissues. Methods: The effect of dopamine D2 receptor agonist quinpirole and D2 receptor antagonist sulpiride was tested on different characteristic features (amplitude, duration and velocity of KCl-induced SD in somatosensory neocortical slices of adult rats. The effect of above-mentioned substances on production of long-term potentiation (LTP in the neocortex was also evaluated. Results: The present data revealed a dose-dependent suppression of the amplitude and duration of SD in the presence of the dopamine D2 receptor antagonist sulpiride in the neocortex. D2 dopamine receptor agonist quinpirole dose-dependently enhanced the amplitude and duration of the neocortical SD. Furthermore, application of D2 receptor antagonist significantly suppressed induction of LTP. Discussion: These results indicate that D2 receptors modulate the initiation of SD in the neocortex. This finding refers to the potential role of D2 receptor antagonist in treatment of migraine pain.

  15. Zero-Outage Cellular Downlink with Fixed-Rate D2D Underlay

    DEFF Research Database (Denmark)

    Kiilerich Pratas, Nuno; Popovski, Petar


    Two of the emerging trends in wireless cellular systems are Device-to-Device (D2D) and Machine-to-Machine (M2M) communications. D2D enables efficient reuse of the licensed spectrum to support localized transmissions, while M2M connections are often characterized by fixed and low transmission rate...

  16. D2-40 in breast cancer: should we detect more vascular emboli? (United States)

    de Mascarel, Isabelle; MacGrogan, Gaëtan; Debled, Marc; Sierankowski, Ghislaine; Brouste, Véronique; Mathoulin-Pélissier, Simone; Mauriac, Louis


    Peritumoral emboli assessed on hematoxylin-eosin-stained slides are taken into account for treatment of patients with operable breast cancer. We assessed whether immunostaining with D2-40 improves the prognostic significance of emboli in a group of tumors with a large immunohistochemical sampling and a long-term follow-up. Topography, number, and extension of hematoxylin-eosin and D2-40 emboli were compared in 94 node-negative breast cancers (median number of immunostained slides per tumor: 3). Metastasis-free survival of patients with or without hematoxylin-eosin and/or D2-40 emboli were evaluated (median follow-up of 178 months). Hematoxylin-eosin emboli were detected in 14 (15%) tumors and were located at distance from the tumor. D2-40 emboli were detected in 39 (41%) tumors and was often multiple (n=30), extensive (n=23), located within (n=13), close to (n=10) or at distance from the tumor (n=16). The 12 distant hematoxylin-eosin and D2-40 emboli were located in the same vessels (seven missed at the first hematoxylin-eosin examination and secondarily diagnosed by D2-40 staining). A difference in metastasis-free survival was found only between patients with no D2-40 emboli and those with distant D2-40 emboli (P=0.02). D2-40 emboli located within or close to the tumor had no prognostic value. Comparing the metastasis-free survival of patients with or without hematoxylin-eosin emboli, the prognostically unfavorable significance of hematoxylin-eosin emboli was improved when taking into account the seven patients with missed emboli at the first examination and secondarily diagnosed by D2-40 staining (P=0.006 vs 0.003). To conclude, D2-40 increases the diagnostic sensitivity of emboli in breast carcinoma and the high incidence of D2-40 emboli might be related to the number of immunostained slides per case. Nevertheless, only distant D2-40+ emboli had a prognostic impact. In practice, D2-40 might be useful to detect missed hematoxylin-eosin emboli especially in cases

  17. Reduced Slc6a15 in Nucleus Accumbens D2-Neurons Underlies Stress Susceptibility. (United States)

    Chandra, Ramesh; Francis, T Chase; Nam, Hyungwoo; Riggs, Lace M; Engeln, Michel; Rudzinskas, Sarah; Konkalmatt, Prasad; Russo, Scott J; Turecki, Gustavo; Iniguez, Sergio D; Lobo, Mary Kay


    Previous research demonstrates that Slc6a15, a neutral amino acid transporter, is associated with depression susceptibility. However, no study examined Slc6a15 in the ventral striatum [nucleus accumbens (NAc)] in depression. Given our previous characterization of Slc6a15 as a striatal dopamine receptor 2 (D2)-neuron-enriched gene, we examined the role of Slc6a15 in NAc D2-neurons in mediating susceptibility to stress in male mice. First, we showed that Slc6a15 mRNA was reduced in NAc of mice susceptible to chronic social defeat stress (CSDS), a paradigm that produces behavioral and molecular adaptations that resemble clinical depression. Consistent with our preclinical data, we observed Slc6a15 mRNA reduction in NAc of individuals with major depressive disorder (MDD). The Slc6a15 reduction in NAc occurred selectively in D2-neurons. Next, we used Cre-inducible viruses combined with D2-Cre mice to reduce or overexpress Slc6a15 in NAc D2-neurons. Slc6a15 reduction in D2-neurons caused enhanced susceptibility to a subthreshold social defeat stress (SSDS) as observed by reduced social interaction, while a reduction in social interaction following CSDS was not observed when Slc6a15 expression in D2-neurons was restored. Finally, since both D2-medium spiny neurons (MSNs) and D2-expressing choline acetyltransferase (ChAT) interneurons express Slc6a15, we examined Slc6a15 protein in these interneurons after CSDS. Slc6a15 protein was unaltered in ChAT interneurons. Consistent with this, reducing Slc5a15 selectively in NAc D2-MSNs, using A2A-Cre mice that express Cre selectively in D2-MSNs, caused enhanced susceptibility to SSDS. Collectively, our data demonstrate that reduced Slc6a15 in NAc occurs in MDD individuals and that Slc6a15 reduction in NAc D2-neurons underlies stress susceptibility. SIGNIFICANCE STATEMENT Our study demonstrates a role for reduced Slc6a15, a neutral amino acid transporter, in nucleus accumbens (NAc) in depression and stress susceptibility. The

  18. Increased plasma d-2-hydroxyglutarate in isocitrate dehydrogenase 2-mutated blastic plasmacytoid dendritic cell neoplasm. (United States)

    Rakheja, Dinesh; Fuda, Franklin; Vandergriff, Travis; Boriack, Richard; Medeiros, Bruno C; Frankel, Arthur E; Chen, Weina


    Blastic plasmacytoid dendritic cell neoplasm is an exceedingly rare hematologic malignancy derived from the precursors of plasmacytoid dendritic cells. Mutations in isocitrate dehydrogenase (IDH) 1 and 2 genes have been discovered in a range of neoplasms including glioma, acute myeloid leukemia, chondrosarcoma, and intrahepatic cholangiocarcinoma. Mutant IDH acquires neomorphic enzymatic activity to generate the oncometabolite d-2-hydroxyglutarate (d-2HG). Here, we describe the first case of an IDH2 R140Q-mutated blastic plasmacytoid dendritic cell neoplasm in a patient with markedly elevated plasma d-2HG. This finding expands the spectrum of neoplasms with increased d-2HG in association with IDH mutation. The roles of IDH mutation and d-2HG in disease pathogenesis and assessment of clinical response are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Clustering Optimization for Out-of-Band D2D Communications

    Directory of Open Access Journals (Sweden)

    A. Paramonov


    Full Text Available Significant increase in multimedia traffic challenges 5G networks in terms of capacity and correspondent QoS parameters. Device-to-device communication paradigm has already become an integral part of 3GPP standards; nevertheless it has not yet been widely deployed due to many different reasons. D2D is expected to leverage implementation of many qualitatively new services and to efficiently accomplish it D2D devices are supposed to form clusters. Due to practical limitations, current D2D implementations are mostly out-of-band and use Wi-Fi Direct. In this paper, we propose a novel model for throughput optimization in out-of-band D2D clusters. We delivered numerical results for different typical cluster member distributions and revealed key functional dependencies. Further, for the first time we compare clustering algorithms for out-of-band D2D and identify effective clustering algorithm that increases network resource utilization rate.

  20. Potent haloperidol derivatives covalently binding to the dopamine D2 receptor. (United States)

    Schwalbe, Tobias; Kaindl, Jonas; Hübner, Harald; Gmeiner, Peter


    The dopamine D 2 receptor (D 2 R) is a common drug target for the treatment of a variety of neurological disorders including schizophrenia. Structure based design of subtype selective D 2 R antagonists requires high resolution crystal structures of the receptor and pharmacological tools promoting a better understanding of the protein-ligand interactions. Recently, we reported the development of a chemically activated dopamine derivative (FAUC150) designed to covalently bind the L94C mutant of the dopamine D 2 receptor. Using FAUC150 as a template, we elaborated the design and synthesis of irreversible analogs of the potent antipsychotic drug haloperidol forming covalent D 2 R-ligand complexes. The disulfide- and Michael acceptor-functionalized compounds showed significant receptor affinity and an irreversible binding profile in radioligand depletion experiments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Detection of lymphovascular invasion by D2-40 (podoplanin) immunoexpression in endometrial cancer. (United States)

    Weber, Sarah K; Sauerwald, Axel; Pölcher, Martin; Braun, Michael; Debald, Manuel; Serce, Nuran Bektas; Kuhn, Walther; Brunagel-Walgenbach, Giesela; Rudlowski, Christian


    Lymph node involvement is a major feature in tumor spread of endometrial cancer and predicts prognosis. Therefore, evaluation of lymph vessel invasion (LVI) in tumor tissue as a predictor for lymph node metastasis is of great importance. Immunostaining of D2-40 (podoplanin), a specific marker for lymphatic endothelial cells, might be able to increase the detection rate of LVI compared with conventional hematoxylin-eosin (H-E) staining. The aim of this retrospective study was to analyze the eligibility of D2-40-based LVI evaluation for the prediction of lymph node metastases and patients' outcome. Immunohistochemical staining with D2-40 monoclonal antibodies was performed on paraffin-embedded tissue sections of 182 patients with primary endometrioid adenocarcinoma treated in 1 gynecologic cancer center. Tumors were screened for the presence of LVI. Correlations with clinicopathological features and clinical outcome were assessed. Immunostaining of D2-40 significantly increased the frequency LVI detection compared with conventional H-E staining. Lymph vessel invasion was identified by D2-40 in 53 (29.1%) of 182 tumors compared with 34 (18.3%) of 182 carcinomas by routine H-E staining (P = 0.001). D2-40 LVI was detectable in 81.0% (17/21) of nodal-positive tumors and significantly predicted lymph node metastasis (P = 0.001). Furthermore, D2-40 LVI was an independent prognostic factor for patients overall survival considering tumor stage, lymph node involvement, and tumor differentiation (P < 0.01). D2-40-negative tumors confined to the inner half of the myometrium showed an excellent outcome (5-year overall survival, 97.8%). D2-40-based LVI assessment improves the histopathological detection of lymphovascular invasion in endometrial cancer. Furthermore, LVI is of prognostic value and predicts lymph node metastasis. D2-40 LVI detection might help to select endometrial cancer patients who will benefit from a lymphadenectomy.

  2. Vitamin D2 versus vitamin D3 supplementation in hemodialysis patients: a comparative pilot study. (United States)

    Daroux, Maïté; Shenouda, Milhad; Bacri, Jean-Louis; Lemaitre, Vincent; Vanhille, Philippe; Bataille, Pierre


    In patients with chronic kidney disease, vitamin D insufficiency is highly prevalent. It can be corrected by supplementation with either vitamin D(2) or vitamin D3. Recent studies in patients without impaired kidney function suggest that vitamin D(3) is more efficient than vitamin D(2) in correcting vitamin D insufficiency. However, no direct comparison has been made in hemodialysis (HD) patients. Thirty-nine HD patients with serum 25-hydroxyvitamin D (25(OH)D) levels =20 ng/mL were enrolled in this comparative, prospective pilot study. They were divided into 3 groups and treated over a 3-month period. Each patient received oral doses of 200,000 international units (IU) vitamin D per month according to the following treatment schedule: (i) vitamin D(2) in small fractionated doses at each HD session, 3 times per week (group D2S); (ii) vitamin D(2) once a month (group D2M); or (iii) vitamin D(3) once a month (group D3M). Changes in serum 25(OH)D levels were measured at the end of the study. Posttreatment serum 25(OH)D levels increased significantly in all groups. The mean ± SD serum 25(OH)D value for group D3M patients (40 ± 13 ng/mL) was significantly higher than that for groups D2M (25 ± 9 ng/mL, p30 ng/mL in 84% of group D3M patients, but in only 15% and 27% of group D2M and D2S subjects, respectively. Vitamin D(3) is more effective than vitamin D(2) in providing adequate 25(OH)D serum levels in HD patients.

  3. Modulation of dopamine D(2) receptor signaling by actin-binding protein (ABP-280). (United States)

    Li, M; Bermak, J C; Wang, Z W; Zhou, Q Y


    Proteins that bind to G protein-coupled receptors have recently been identified as regulators of receptor anchoring and signaling. In this study, actin-binding protein 280 (ABP-280), a widely expressed cytoskeleton-associated protein that plays an important role in regulating cell morphology and motility, was found to associate with the third cytoplasmic loop of dopamine D(2) receptors. The specificity of this interaction was originally identified in a yeast two-hybrid screen and confirmed by protein binding. The functional significance of the D(2) receptor-ABP-280 association was evaluated in human melanoma cells lacking ABP-280. D(2) receptor agonists were less potent in inhibiting forskolin-stimulated cAMP production in these cells. Maximal inhibitory responses of D(2) receptor activation were also reduced. Further yeast two-hybrid experiments showed that ABP-280 association is critically dependent on the carboxyl domain of the D(2) receptor third cytoplasmic loop, where there is a potential serine phosphorylation site (S358). Serine 358 was replaced with aspartic acid to mimic the effects of receptor phosphorylation. This mutant (D(2)S358D) displayed compromised binding to ABP-280 and coupling to adenylate cyclase. PKC activation also generated D(2) receptor signaling attenuation, but only in ABP-containing cells, suggesting a PKC regulatory role in D(2)-ABP association. A mechanism for these results may be derived from a role of ABP-280 in the clustering of D(2) receptors, as determined by immunocytochemical analysis in ABP-deficient and replete cells. Our results suggest a new molecular mechanism of modulating D(2) receptor signaling by cytoskeletal protein interaction.

  4. Gilles de la Tourette syndrome is associated with hypermethylation of the dopamine D2 receptor gene. (United States)

    Müller-Vahl, Kirsten R; Loeber, Gesa; Kotsiari, Alexandra; Müller-Engling, Linda; Frieling, Helge


    Several lines of evidence support a "dopaminergic hypothesis" in the pathophysiology of Gilles de la Tourette syndrome (TS). The aim of this study was to investigate for the first time epigenetic changes in DNA methylation in different dopamine genes in adult patients with TS. We included 51 well characterized adult patients with TS (41 males, 10 females, mean age = 35 ± 12.6 years, range, 18-71 years) and compared results with data from a group of 51 sex- and age-matched healthy controls. Bisulfite sequencing was used to measure peripheral DNA methylation of the dopamine transporter (DAT), the dopamine D2 receptor (DRD2), and the catechol-O-methyltransferase (COMT) genes. Compared to healthy controls, patients with TS showed significantly elevated methylation level of the DRD2 gene that positively correlated with tic severity. In contrast, DAT methylation was lower in more severely affected patients. Our results provide evidence for a role of altered epigenetic regulation of dopaminergic genes in the pathophysiology of TS. While DRD2 hypermethylation seems to be directly related to the neurobiology of TS that may lead to dopaminergic dysfunction resulting in enhanced thalamo-cortical movement-stimulating activity, DAT hypomethylation might reflect a secondary mechanism in order to compensate for increased dopaminergic signal transduction due to DRD2 hypermethylation. In addition, it can be speculated that spontaneous fluctuations of tics may be caused by short-term alterations of methylation levels of dopaminergic genes resulting in dynamic changes of tonic/phasic dopaminergic signaling in the striatum and thalamo-cortical output pathways. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. +-d2-+

    Indian Academy of Sciences (India)

    CLASSROOM. Image Formation Through Extended Apertures. It is a common experience that the images of the rising or the setting sun through sky-light openings are often quite well defined. These openings could be circular, ... object go through the pinhole and form an inverted image on the opposite side of the pinhole.

  6. A Portable Rubidium Fountain (United States)


    and K. Gibble, 2004, “Phase variations in microwave cavities for atomic clocks,” Metrologia , 41, 376-378. [7] S. R. Jefferts, J. H. Shirley, N...phase errors in atomic clocks,” Metrologia , 47, 534-551. 42 nd Annual Precise Time and Time Interval (PTTI) Meeting 320

  7. Rubidium Frequency Standard Study. (United States)


    considered to be a result of physical phenom- 7ena related to the surface adsorption. The buffer gas absorption, i.e., dif- fusion into the cell wall material...can best be described in an example of Rb resonance cells used in the nucler magnetic resonance (NMR) gyro developed in this laboratory. The NKR cell

  8. Cannabidiol is a partial agonist at dopamine D2High receptors, predicting its antipsychotic clinical dose. (United States)

    Seeman, P


    Although all current antipsychotics act by interfering with the action of dopamine at dopamine D2 receptors, two recent reports showed that 800 to 1000 mg of cannabidiol per day alleviated the signs and symptoms of schizophrenia, although cannabidiol is not known to act on dopamine receptors. Because these recent clinical findings may indicate an important exception to the general rule that all antipsychotics interfere with dopamine at dopamine D2 receptors, the present study examined whether cannabidiol acted directly on D2 receptors, using tritiated domperidone to label rat brain striatal D2 receptors. It was found that cannabidiol inhibited the binding of radio-domperidone with dissociation constants of 11 nm at dopamine D2High receptors and 2800 nm at dopamine D2Low receptors, in the same biphasic manner as a dopamine partial agonist antipsychotic drug such as aripiprazole. The clinical doses of cannabidiol are sufficient to occupy the functional D2High sites. it is concluded that the dopamine partial agonist action of cannabidiol may account for its clinical antipsychotic effects.

  9. Cognition and Dopamine D2 Receptor Availability in the Striatum in Older Patients with Schizophrenia. (United States)

    Rajji, Tarek K; Mulsant, Benoit H; Nakajima, Shinichiro; Caravaggio, Fernando; Suzuki, Takefumi; Uchida, Hiroyuki; Gerretsen, Philip; Mar, Wanna; Pollock, Bruce G; Mamo, David C; Graff-Guerrero, Ariel


    To assess the impact of reducing the dose of antipsychotics on cognition and dopaminergic D2 receptor availability in the whole striatum, and identify their relationship in patients with schizophrenia aged 50 years or older. Open-label prospective PET [11C]-raclopride study. A tertiary care center outpatient setting. Thirty-seven clinically stable participants with schizophrenia or schizoaffective disorder, aged 50 years or greater, and having been treated with olanzapine or risperidone monotherapy at the same dose for at least 6 months. Gradual reduction in their olanzapine or risperidone daily dose of up to 40%. Clinical and cognitive assessments, and [11C]-raclopride PET to determine D2 receptor availability at baseline and after the dose reduction. Main outcome measures were overall cognition and D2 receptor availability in whole striatum. Reducing the antipsychotic dose resulted in an increase in D2 receptor availability in the whole striatum and an association between D2 receptor availability and overall cognition despite lack of change in the latter. There was also an association between change in D2 receptor availability and change in overall cognition. Our findings suggest that optimizing D2 receptor availability by reducing antipsychotic dose allows this system to contribute more significantly to cognitive function in patients with schizophrenia. This uncovered association could be harnessed by cognitive-enhancing interventions. Copyright © 2017 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  10. A peptide disrupting the D2R-DAT interaction protects against dopamine neurotoxicity. (United States)

    Su, Ping; Liu, Fang


    Dopamine reuptake from extracellular space to cytosol leads to accumulation of dopamine, which triggers neurotoxicity in dopaminergic neurons. Previous studies have shown that both dopamine D2 receptor (D2R) and dopamine transporter (DAT) are involved in dopamine neurotoxicity. However, blockade of either D2R or DAT causes side effects due to antagonism of other physiological functions of these two proteins. We previously found that DAT can form a protein complex with D2R and its cell surface expression is facilitated via D2R-DAT interaction, which regulates dopamine reuptake and intracellular dopamine levels. Here we found that an interfering peptide (DAT-S1) disrupting the D2R-DAT interaction protects neurons against dopamine neurotoxicity, and this effect is mediated by inhibiting DAT cell surface expression and inhibiting both caspase-3 and PARP-1 cleavage. This study demonstrates the role of the D2R-DAT complex in dopamine neurotoxicity and investigated the potential mechanisms, which might help better understand the mechanisms of dopamine neurotoxicity. The peptide may provide some insights to improve treatments for dopamine neurotoxicity and related diseases, such as Parkinson's disease, as well as methamphetamine- and 3,4-methsylenedioxy methamphetamine-induced neurotoxicity. Copyright © 2017. Published by Elsevier Inc.

  11. Resolvin D2 is a potent regulator of leukocytes and controls microbial sepsis. (United States)

    Spite, Matthew; Norling, Lucy V; Summers, Lisa; Yang, Rong; Cooper, Dianne; Petasis, Nicos A; Flower, Roderick J; Perretti, Mauro; Serhan, Charles N


    A growing body of evidence indicates that resolution of acute inflammation is an active process. Resolvins are a new family of lipid mediators enzymatically generated within resolution networks that possess unique and specific functions to orchestrate catabasis, the phase in which disease declines. Resolvin D2 (RvD2) was originally identified in resolving exudates, yet its individual contribution in resolution remained to be elucidated. Here, we establish RvD2's potent stereoselective actions in reducing excessive neutrophil trafficking to inflammatory loci. RvD2 decreased leukocyte-endothelial interactions in vivo by endothelial-dependent nitric oxide production, and by direct modulation of leukocyte adhesion receptor expression. In mice with microbial sepsis initiated by caecal ligation and puncture, RvD2 sharply decreased both local and systemic bacterial burden, excessive cytokine production and neutrophil recruitment, while increasing peritoneal mononuclear cells and macrophage phagocytosis. These multi-level pro-resolving actions of RvD2 translate to increased survival from sepsis induced by caecal ligation and puncture and surgery. Together, these results identify RvD2 as a potent endogenous regulator of excessive inflammatory responses that acts via multiple cellular targets to stimulate resolution and preserve immune vigilance.

  12. NeuroD2 regulates the development of hippocampal mossy fiber synapses

    Directory of Open Access Journals (Sweden)

    Wilke Scott A


    Full Text Available Abstract Background The assembly of neural circuits requires the concerted action of both genetically determined and activity-dependent mechanisms. Calcium-regulated transcription may link these processes, but the influence of specific transcription factors on the differentiation of synapse-specific properties is poorly understood. Here we characterize the influence of NeuroD2, a calcium-dependent transcription factor, in regulating the structural and functional maturation of the hippocampal mossy fiber (MF synapse. Results Using NeuroD2 null mice and in vivo lentivirus-mediated gene knockdown, we demonstrate a critical role for NeuroD2 in the formation of CA3 dendritic spines receiving MF inputs. We also use electrophysiological recordings from CA3 neurons while stimulating MF axons to show that NeuroD2 regulates the differentiation of functional properties at the MF synapse. Finally, we find that NeuroD2 regulates PSD95 expression in hippocampal neurons and that PSD95 loss of function in vivo reproduces CA3 neuron spine defects observed in NeuroD2 null mice. Conclusion These experiments identify NeuroD2 as a key transcription factor that regulates the structural and functional differentiation of MF synapses in vivo.

  13. A Practical Resource Management Scheme for Cellular Underlaid D2D Networks

    Directory of Open Access Journals (Sweden)

    Tae-Won Ban


    Full Text Available In this paper, we investigate a resource management scheme for cellular underlaid device-to-device (D2D communications, which are an integral part of mobile caching networks. D2D communications are allowed to share radio resources with cellular communications as long as the generating interference of D2D communications satisfies an interference constraint to secure cellular communications. Contrary to most of the other studies, we propose a distributed resource management scheme for cellular underlaid D2D communications focusing on a practical feasibility. In the proposed scheme, the feedback of channel information is not required because all D2D transmitters use a fixed transmit power and every D2D transmitter determines when to transmit data on its own without centralized control. We analyze the average sum-rates to evaluate the proposed scheme and compare them with optimal values, which can be achieved when a central controller has the perfect entire channel information and the full control of all D2D communications. Our numerical results show that the average sum-rates of the proposed scheme approach the optimal values in low or high signal-to-noise power ratio (SNR regions. In particular, the proposed scheme achieves almost optimal average sum-rates in the entire SNR values in practical environments.

  14. Dopamine D2 Receptors Enhance Population Dynamics in Primate Prefrontal Working Memory Circuits. (United States)

    Ott, Torben; Nieder, Andreas


    Working memory is associated with persistent activity in the prefrontal cortex (PFC). The neuromodulator dopamine, which is released by midbrain neurons projecting into the frontal lobe, influences PFC neurons and networks via the dopamine D1 (D1R) and the D2 receptor (D2R) families. Although behavioral, clinical and computational evidence suggest an involvement of D2Rs in working memory, a neuronal explanation is missing. We report an enhancement of persistent working memory responses of PFC neurons after iontophoretically stimulating D2Rs in monkeys memorizing the number of items in a display. D2R activation improved working memory representation at the population level and increased population dynamics during the transition from visual to mnemonic representations. Computational modeling suggests that D2Rs act by modulating interneuron-to-pyramidal signaling. By increasing the population's response dynamics, D2Rs might put PFC networks in a more flexible state and enhance the neurons' working memory coding, thereby controlling dynamic cognitive control. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail:

  15. Role of dopamine D2 receptors in plasticity of stress-induced addictive behaviours. (United States)

    Sim, Hye-Ri; Choi, Tae-Yong; Lee, Hyo Jin; Kang, Eun Young; Yoon, Sehyoun; Han, Pyung-Lim; Choi, Se-Young; Baik, Ja-Hyun


    Dopaminergic systems are implicated in stress-related behaviour. Here we investigate behavioural responses to chronic stress in dopamine D2 receptor knockout mice and find that anxiety-like behaviours are increased compared with wild-type mice. Repeated stress exposure suppresses cocaine-induced behavioural sensitization, cocaine-seeking and relapse behaviours in dopamine D2 receptor knockout mice. Cocaine challenge after drug withdrawal in cocaine-experienced wild-type or dopamine D2 receptor knockout mice is associated with inhibition of long-term depression in the nucleus accumbens, and chronic stress during withdrawal prevents inhibition after cocaine challenge in cocaine-experienced dopamine D2 receptor knockout mice, but not in wild-type mice. Lentiviral-induced knockdown of dopamine D2 receptors in the nucleus accumbens of wild-type mice does not affect basal locomotor activity, but confers stress-induced inhibition of the expression of cocaine-induced behavioural sensitization. Stressed mice depleted of dopamine D2 receptors do not manifest long-term depression inhibition. Our results suggest that dopamine D2 receptors have roles in regulating synaptic modification triggered by stress and drug addiction.

  16. Dopamine D2High receptors stimulated by phencyclidines, lysergic acid diethylamide, salvinorin A, and modafinil. (United States)

    Seeman, Philip; Guan, Hong-Chang; Hirbec, Hélène


    Although it is commonly stated that phencyclidine is an antagonist at ionotropic glutamate receptors, there has been little measure of its potency on other receptors in brain tissue. Although we previously reported that phencyclidine stimulated cloned-dopamine D2Long and D2Short receptors, others reported that phencyclidine did not stimulate D2 receptors in homogenates of rat brain striatum. This study, therefore, examined whether phencyclidine and other hallucinogens and psychostimulants could stimulate the incorporation of [(35)S]GTP-gamma-S into D2 receptors in homogenates of rat brain striatum, using the same conditions as previously used to study the cloned D2 receptors. Using 10 microM dopamine to define 100% stimulation, phencyclidine elicited a maximum incorporation of 46% in rat striata, with a half-maximum concentration of 70 nM for phencyclidine, when compared with 80 nM for dopamine, 89 nM for salvinorin A (48 nM for D2Long), 105 nM for lysergic acid diethylamide (LSD), 120 nM for R-modafinil, 710 nM for dizocilpine, 1030 nM for ketamine, and >10,000 nM for S-modafinil. These compounds also inhibited the binding of the D2-selective ligand [(3)H]domperidone. The incorporation was inhibited by the presence of 200 microM guanylylimidodiphosphate and also by D2 blockade, using 10 microM S-sulpiride, but not by D1 blockade with 10 microM SCH23390. Hypertonic buffer containing 150 mM NaCl inhibited the stimulation by phencyclidine, which may explain negative results by others. It is concluded that phencyclidine and other psychostimulants and hallucinogens can stimulate dopamine D2 receptors at concentrations related to their behavioral actions.

  17. Can Full Duplex reduce the discovery time in D2D Communication?

    DEFF Research Database (Denmark)

    Gatnau, Marta; Berardinelli, Gilberto; Mahmood, Nurul Huda


    Device-to-device (D2D) communication is considered as one of the key technologies to support new types of services, such as public safety and proximity-based applications. D2D communication requires a discovery phase, i.e., the node awareness procedure prior to the communication phase. Conventional...... of full duplex in providing fast discovery for the next 5th generation (5G) system supporting D2D communication is investigated. A design for such system is presented and evaluated via simulations, showing that full duplex can accelerate the discovery phase by supporting a higher transmission probability...

  18. Dopamine D1-D2 receptor heteromer signaling pathway in the brain: emerging physiological relevance

    Directory of Open Access Journals (Sweden)

    Hasbi Ahmed


    Full Text Available Abstract Dopamine is an important catecholamine neurotransmitter modulating many physiological functions, and is linked to psychopathology of many diseases such as schizophrenia and drug addiction. Dopamine D1 and D2 receptors are the most abundant dopaminergic receptors in the striatum, and although a clear segregation between the pathways expressing these two receptors has been reported in certain subregions, the presence of D1-D2 receptor heteromers within a unique subset of neurons, forming a novel signaling transducing functional entity has been shown. Recently, significant progress has been made in elucidating the signaling pathways activated by the D1-D2 receptor heteromer and their potential physiological relevance.

  19. Tunable line width all solid state double spectral line sodium beacon laser (United States)

    Lu, Yanhua; Zhang, Lei; Xu, Xiafei; Ren, Huaijin; Wei, Bin; Yuan, Liao; Gong, Shenggang; Li, Tao; Gu, Jingliang; Wan, Min; Fan, Guobin


    We developed a tunable-line-width 101 W average-power all-solid-state 589nm double spectral line sodium beacon laser. The laser was based on the technical route of 1064nm and 1319nm Nd:YAG laser extra cavity sum frequency generation. The laser contained two spectral lines: 589.1591 nm and 589.1571 nm. The former line was matched to the sodium D2a absorption line with the average power of 81W, while the other line was matched to the sodium D2b absorption line with the average power of 20W. The beam quality of the two spectral line lasers was both less than 1.3. The two lasers were polarized-combined to transmit coaxially. The initial line width of the laser was about 0.3GHz, which was in the comb-like discrete structure of about three longitudinal modes. We used a white noise generator to modulate the 1064nm single frequency seed laser in frequency domain. The line width's tunability was accomplished by tuning the driving power of the white noise generator. The final line width tuning range of the 589nm laser was 0.3GHz to 1.1GHz.

  20. Different effects of chronic THC on the neuroadaptive response of dopamine D2/3 receptor-mediated signaling in roman high- and roman low-avoidance rats. (United States)

    Tournier, Benjamin B; Dimiziani, Andrea; Tsartsalis, Stergios; Millet, Philippe; Ginovart, Nathalie


    The Roman high (RHA)- and low (RLA)-avoidance rat sublines have been identified as an addiction-prone and addiction-resistant phenotype based on their high vs. low locomotor responsiveness to novelty and high vs. low ability to develop neurochemical and behavioral sensitization to psychostimulants, respectively. Most studies though have focused on psychostimulants and little is known about the neuroadaptive response of these two lines to cannabinoids. This study investigated the effects of chronic exposure to Δ 9 -tetrahydrocannabinol (THC) on dopamine D 2/3 receptor (D 2/3 R) availabilities and functional sensitivity in the mesostriatal system of RHA and RLA rats. At baseline, RLA rats exhibited higher densities of mesostriatal D2/3R but lower levels of striatal CB 1 R mRNA and displayed a lower locomotor response to acute THC as compared to RHAs. Following chronic THC treatment, striking changes in D 2/3 R signaling were observed in RLA but not in RHA rats, namely an increased availability and functional supersensitivity of striatal D 2/3 R, as evidenced by a supersensitive psychomotor response to the D 2/3 R agonist quinpirole. Moreover, in RLA rats, the lower was the locomotor response to acute THC, the higher was the psychomotor response to quinpirole following chronic THC. These results showing a greater neuroadaptive response of RLA vs. RHA rats to chronic THC thus contrast with previous studies showing a resistance to neuroadaptive response of RLAs to psychostimulants, This suggests that, contrasting with their low proneness to psychostimulant drug-seeking, RLAs may exhibit a heightened proneness to cannabinoid drug-seeking as compared to RHA rats. © 2017 Wiley Periodicals, Inc.

  1. A coalitional graph game framework for network coding-aided D2D communication

    National Research Council Canada - National Science Library

    Zhao, Yulei; Li, Yong; Ding, Zhiguo; Ge, Ning; Poor, H Vincent


    .... In this paper, a coalitional graph game framework is proposed to jointly accomplish resource allocation and relay selection, two challenging problems in network coding-aided D2D communication networks...

  2. Dexamethasone Induces Cardiomyocyte Terminal Differentiation via Epigenetic Repression of Cyclin D2 Gene

    National Research Council Canada - National Science Library

    Gay, Maresha S; Dasgupta, Chiranjib; Li, Yong; Kanna, Angela; Zhang, Lubo


    .... Yet mechanisms remain undetermined. The present study tested the hypothesis that the direct effect of glucocorticoid receptor-mediated epigenetic repression of cyclin D2 gene in the cardiomyocyte plays a key role in the dexamethasone...

  3. Relationship of frontal D2/3 binding potentials to cognition

    DEFF Research Database (Denmark)

    Fagerlund, Birgitte; Pinborg, Lars H; Mortensen, Erik Lykke


    Studies of in vivo dopamine receptors in schizophrenia have mostly focused on D2 receptors in striatal areas or on D1 receptors in cortex. No previous study has examined the correlation between cortical dopamine D2/3 receptor binding potentials and cognition in schizophrenia patients. The objective...... single-photon emission computerized tomography with the D2/3-receptor ligand [123I]epidepride, co-registered with structural magnetic resonance imaging and correlated to cognitive measures. Participants were 24 antipsychotic-naive, first-episode schizophrenia patients and 20 healthy controls matched......, in schizophrenia patients compared to healthy people. The results suggest that cortical D2/3 receptor function may be more involved in some cognitive functions (i.e. attention, fluency and planning) in patients with schizophrenia than in healthy people, suggesting that information processing in schizophrenia may...

  4. High Line

    DEFF Research Database (Denmark)

    Kiib, Hans


    factories and warehouses on Gansevoort Street. Today the High Line is a beautiful park covered with new tiles, viewing platforms and smaller recreational areas. The park bridge has simple, uniform, urban fittings and features a variety of flowering plants, grasses, shrubs and trees from around the world......, and galleries. With the High Line, a new urban architectural typology has been created that is aesthetically enriching and sets new standards for urban transformation and urban life. “The park accommodates the wild, the cultivated, the intimate and the social. Access points are durational experiences designed...

  5. Dopamine D2 receptor radiotracers [{sup 11}C](+)-PHNO and [{sup 3}H]raclopride are indistinguishably inhibited by D2 agonists and antagonists ex vivo

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Patrick N. [Institute of Medical Science, University of Toronto, Toronto, Ontario, M5S 1A8 (Canada)], E-mail:; Kapur, Shitij [Department of Psychiatry, University of Toronto, Toronto, Ontario, M5S 1A8 (Canada); PET Center, Center for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Seeman, Philip [Department of Psychiatry, University of Toronto, Toronto, Ontario, M5S 1A8 (Canada); Department of Pharmacology, University of Toronto, Toronto, Ontario, M5S 1A8 (Canada); Wilson, Alan A. [Department of Psychiatry, University of Toronto, Toronto, Ontario, M5S 1A8 (Canada); PET Center, Center for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada)


    Introduction: In vitro, the dopamine D2 receptor exists in two states, with high and low affinity for agonists. The high-affinity state is the physiologically active state thought to be involved in dopaminergic illnesses such as schizophrenia. The positron emission tomography radiotracer [{sup 11}C](+)-PHNO ([{sup 11}C](+)-4-propyl-3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4] oxazin-9-o l), being a D2 agonist, should selectively label the high-affinity state at tracer dose and therefore be more susceptible to competition by agonist as compared to the antagonist [{sup 3}H]raclopride, which binds to both affinity states. Methods: We tested this prediction using ex vivo dual-radiotracer experiments in conscious rats. D2 antagonists (haloperidol or clozapine), a partial agonist (aripiprazole), a full agonist [(-)-NPA] or the dopamine-releasing drug amphetamine (AMPH) were administered to rats prior to an intravenous coinjection of [{sup 11}C](+)-PHNO and [{sup 3}H]raclopride. Rats were sacrificed 60 min after radiotracer injection. Striatum, cerebellum and plasma samples were counted for {sup 11}C and {sup 3}H. The specific binding ratio {l_brace}SBR, i.e., [%ID/g (striatum)-%ID/g (cerebellum)]/(%ID/g (cerebellum){r_brace} was used as the outcome measure. Results: In response to D2 antagonists, partial agonist or full agonist, [{sup 11}C](+)-PHNO and [{sup 3}H]raclopride SBRs responded indistinguishably in terms of both ED{sub 50} and Hill slope (e.g., (-)-NPA ED{sub 50} values are 0.027 and 0.023 mg/kg for [{sup 11}C](+)-PHNO and [{sup 3}H]raclopride, respectively). In response to AMPH challenge, [{sup 11}C](+)-PHNO and [{sup 3}H]raclopride SBRs were inhibited to the same degree. Conclusions: We have shown that the SBRs of [{sup 11}C](+)-PHNO- and [{sup 3}H]raclopride do not differ in their response to agonist challenge. These results do not support predictions of the in vivo binding behavior of a D2 agonist radiotracer and cast some doubt on the in vivo

  6. UniversAAL - Execution environment installation packages and hardware abstraction layer (D2.1-B)


    Furfari, Francesco; Girolami, Michele; Owda, Zaher; Tazari, Saied


    This document corresponds to deliverable D2.1 of type "Prototype". It provides a report about software development within Task 2.1 "Create the universAAL Execution Environment and Hardware Abstraction Layer". The requirements and the scope of D2.1 are equivalent to those defined among the following three expert groups: Middleware, Local Device Discovery and Integration (LDDI), and Security. Each one of these Expert Groups provides the specification of the software under development in compari...

  7. Implementasi Sistem Operasi Embedded IGN Pada Board ALIX3d2


    Arif, Sahrul; Febridiani, Lintang Dwi


    We propose an implementation of IGN embedded operating system for ALIX3d2 board. An embedded operating system have been successfully built before. This embedded operating system was rebuilt then to be implemented on ALIX3d2 board. Re-selection of hardware drivers and packages are done on kernel compilation process, to obtain a perfectly match kernel. Tests are conducted on system running to see correctness factor.Tests are also done by comparing various parameters with the previously develope...

  8. Systemic blockade of D2-like dopamine receptors facilitates extinction of conditioned fear in mice


    Ponnusamy, Ravikumar; Nissim, Helen A.; Barad, Mark


    Extinction of conditioned fear in animals is the explicit model of behavior therapy for human anxiety disorders, including panic disorder, obsessive-compulsive disorder, and post-traumatic stress disorder. Based on previous data indicating that fear extinction in rats is blocked by quinpirole, an agonist of dopamine D2 receptors, we hypothesized that blockade of D2 receptors might facilitate extinction in mice, while agonists should block extinction, as they do in rats. One day after fear con...

  9. Role of D2 dopamine receptors of the ventral pallidum in inhibitory avoidance learning. (United States)

    Lénárd, László; Ollmann, Tamás; László, Kristóf; Kovács, Anita; Gálosi, Rita; Kállai, Veronika; Attila, Tóth; Kertes, Erika; Zagoracz, Olga; Karádi, Zoltán; Péczely, László


    In our present experiments, the role of D2 dopamine (DA) receptors of the ventral pallidum (VP) was investigated in one trial step-through inhibitory avoidance paradigm. Animals were shocked 3 times in the conditioning trial, with 0.5mA current for 1s. Subsequently bilateral microinjection of the D2 DA receptor agonist quinpirole was administered into the VP in three doses (0.1μg, 1.0μg or 5.0μg in 0.4μl saline). We also applied the D2 DA receptor antagonist sulpiride (0.4μg in 0.4μl saline) alone or 15min prior to the agonist treatment to elucidate whether the agonist effect was specific for the D2 DA receptors. Control animals received saline. In a supplementary experiment, it was also investigated whether application of the same conditioning method leads to the formation of short-term memory in the experimental animals. In the experiment with the D2 DA receptor agonist, only the 0.1μg quinpirole increased significantly the step-through latency during the test trials: retention was significant compared to the controls even 2 weeks after conditioning. The D2 DA receptor antagonist sulpiride pretreatment proved that the effect was due to the agonist induced activation of the D2 DA receptors of the VP. The supplementary experiment demonstrated that short-term memory is formed after conditioning in the experimental animals, supporting that the agonist enhanced memory consolidation in the first two experiments. Our results show that the activation of the D2 DA receptors in the VP facilitates memory consolidation as well as memory-retention in inhibitory avoidance paradigm. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Evaluation of the recurrence pattern of gastric cancer after laparoscopic gastrectomy with D2 lymphadenectomy. (United States)

    Kawamura, Yuichiro; Satoh, Seiji; Umeki, Yusuke; Ishida, Yoshinori; Suda, Koichi; Uyama, Ichiro


    The aim of this study was to analyze the oncological aspects of gastric cancer following laparoscopic gastrectomy with D2 lymphadenectomy (LG-D2). We retrospectively evaluated the long-term outcomes of 354 patients who underwent LG-D2 for primary gastric cancer. Recurrence patterns and predictors of peritoneal metastasis were analyzed. Median follow-up time was 43.8 months. Five-year overall survival rates for yp/pStages I, II, and III gastric cancer were 93.7, 78.5, and 42.2 %, respectively. Recurrence was observed in 86 patients. Peritoneal metastasis was the most frequent recurrence pattern (n = 51), followed by hepatic metastasis (n = 17). Lymphatic recurrence at distant sites was observed in 10 patients. No locoregional lymph node metastasis or local recurrence was seen. Nine of 51 cases of peritoneal recurrence were detected by probe laparoscopy. Peritoneal recurrence rates were significantly higher in yp/pT4 and yp/pN3 diseases compared with yp/pT ≤ 3 and yp/pN ≤ 2 diseases. Multivariate analyses demonstrated that yp/pT4, yp/pN3, tumor size ≥70 mm, vascular invasion, and undifferentiated tumors were predictors of peritoneal recurrence following LG-D2. Long-term outcomes of gastric cancer following LG-D2, including recurrence patterns and predictors of peritoneal metastasis, were comparable to those following open D2 gastrectomy. LG-D2 showed good local control. Probe laparoscopy after LG may be effective in detecting peritoneal recurrence, which is not determined with less invasive examinations, including a CT scan. Future large-scale prospective studies are desirable to evaluate not only surgical but also oncological benefits and safety of LG-D2 for advanced gastric cancer.

  11. Modeling Cellular Networks with Full Duplex D2D Communication: A Stochastic Geometry Approach

    KAUST Repository

    Ali, Konpal S.


    Full-duplex (FD) communication is optimistically promoted to double the spectral efficiency if sufficient self-interference cancellation (SIC) is achieved. However, this is not true when deploying FD-communication in a large-scale setup due to the induced mutual interference. Therefore, a large-scale study is necessary to draw legitimate conclusions about gains associated with FD-communication. This paper studies the FD operation for underlay device-to-device (D2D) communication sharing the uplink resources in cellular networks. We propose a disjoint fine-tuned selection criterion for the D2D and FD modes of operation. Then, we develop a tractable analytical paradigm, based on stochastic geometry, to calculate the outage probability and rate for cellular and D2D users. The results reveal that even in the case of perfect SIC, due to the increased interference injected to the network by FD-D2D communication, having all proximity UEs transmit in FD-D2D is not beneficial for the network. However, if the system parameters are carefully tuned, non-trivial network spectral-efficiency gains (64% shown) can be harvested. We also investigate the effects of imperfect SIC and D2D-link distance distribution on the harvested FD gains.

  12. D2-Thr92Ala, thyroid hormone levels and biochemical hypothyroidism in preeclampsia. (United States)

    Procopciuc, Lucia Maria; Caracostea, Gabriela; Hazi, Georgeta; Nemeti, Georgiana; Stamatian, Florin


    To identify if there is a relationship between the deiodinase D2-Thr92Ala genetic variant, thyroid hormone levels and biochemical hypothyroidism in preeclampsia. We genotyped 125 women with preeclampsia and 131 normal pregnant women using PCR-RFLP. Serum thyroid hormone levels were determined using ELISA. Our study showed higher TSH and FT4 levels and lower FT3 levels in women with preeclampsia compared to normal pregnant women, with statistical significance for women with mild and severe preeclampsia. The risk to develop pregnancy-induced hypertension (PIH), mild or severe preeclampsia was increased in carriers of at least one D2-Ala92 allele. TSH and FT4 levels were significantly higher and FT3 levels were significantly lower in preeclamptic women with severe preeclampsia if they carried the D2-Ala92 allele compared to non-carriers. Pregnant women with PIH and mild preeclampsia, carriers of at least one D2-Ala92 allele, delivered at lower gestational age neonates with a lower birth weight compared to non-carriers, but the results were statistically significant only in severe preeclampsia. The D2-Thr92Ala genetic variant is associated with the severity and the obstetric outcome of preeclampsia, and it also influences thyroid hormone levels. The study demonstrates non-thyroidal biochemical hypothyroidism - as a result of deiodination effects due to D2 genotypes.

  13. Effects of dopamine D2/D3 receptor antagonism on human planning and spatial working memory. (United States)

    Naef, M; Müller, U; Linssen, A; Clark, L; Robbins, T W; Eisenegger, C


    Psychopharmacological studies in humans suggest important roles for dopamine (DA) D2 receptors in human executive functions, such as cognitive planning and spatial working memory (SWM). However, studies that investigate an impairment of such functions using the selective DA D2/3 receptor antagonist sulpiride have yielded inconsistent results, perhaps because relatively low doses were used. We believe we report for the first time, the effects of a higher (800 mg p.o.) single dose of sulpiride as well as of genetic variation in the DA receptor D2 gene (DA receptor D2 Taq1A polymorphism), on planning and working memory. With 78 healthy male volunteers, we apply a between-groups, placebo-controlled design. We measure outcomes in the difficult versions of the Cambridge Neuropsychological Test Automated Battery One-Touch Stockings of Cambridge and the self-ordered SWM task. Volunteers in the sulpiride group showed significant impairments in planning accuracy and, for the more difficult problems, in SWM. Sulpiride administration speeded response latencies in the planning task on the most difficult problems. Volunteers with at least one copy of the minor allele (A1+) of the DA receptor D2 Taq1A polymorphism showed better SWM capacity, regardless of whether they received sulpiride or placebo. There were no effects on blood pressure, heart rate or subjective sedation. In sum, a higher single dose of sulpiride impairs SWM and executive planning functions, in a manner independent of the DA receptor D2 Taq1A polymorphism.

  14. Phasic dopamine release drives rapid activation of striatal D2-receptors (United States)

    Marcott, Pamela F; Mamaligas, Aphroditi A; Ford, Christopher P


    Summary Striatal dopamine transmission underlies numerous goal-directed behaviors. Medium spiny neurons (MSNs) are a major target of dopamine in the striatum. However, as dopamine does not directly evoke a synaptic event in MSNs, the time course of dopamine signaling in these cells remains unclear. To examine how dopamine release activates D2-receptors on MSNs, G-protein activated inwardly rectifying potassium (GIRK2; Kir 3.2) channels were virally overexpressed in the striatum and the resulting outward currents were used as a sensor of D2-receptor activation. Electrical and optogenetic stimulation of dopamine terminals evoked robust D2-receptor inhibitory post-synaptic currents (IPSCs) in GIRK2-expressing MSNs that occurred in under a second. Evoked D2-IPSCs could be driven by repetitive stimulation and were not occluded by background dopamine tone. Together, the results indicate that D2-receptors on MSNs exhibit functional low affinity and suggest that striatal D2-receptors can encode both tonic and phasic dopamine signals. PMID:25242218

  15. Terahertz Spectroscopy and Global Analysis of the Bending Vibrations of ^{12}C_2H_2 and ^{12}C_2D_2 (United States)

    Yu, Shanshan; Drouin, Brian J.; Pearson, John C.; Pickett, Herbert M.; Lattanzi, Valerio; Walters, Adam


    Symmetric molecules have no permanent dipole moment and are undetectable by rotational spectroscopy. Their interstellar observations have previously been limited to mid-infrared vibration-rotation spectroscopy. Although relatively weak, vibrational difference bands provide a means for detection of non polar molecules by terahertz techniques with microwave precision. Herschel, SOFIA, and ALMA have the potential to identify a number of difference bands of light symmetric species, e.g., C_2H_2, CH_4 and C_3. This paper reports the results of the laboratory study on ^{12}C_2H_2 and ^{12}C_2D_2. The symmetric isotopomers of acetylene have two bending modes, the trans bending ν_4 (^1{π}_g), and the cis bending ν_5 (^1{π}_u). For ^{12}C_2H_2, the two bending modes occur at 612 and 729 cm^{-1}, respectively. For ^{12}C_2D_2, the two bending modes occur at 511 and 538 cm^{-1}. The ν_5-ν_4 difference bands are allowed and occur in the microwave, terahertz, and far-infrared wavelengths, with band origins at 117 cm^{-1} (3500 GHz) for ^{12}C_2H_2 and 27 cm^{-1} (900 GHz) for ^{12}C_2D_2. Two hundred and fifty-one ^{12}C_2D_2 transitions, which are from ν_5-ν_4, (ν_5+ν_4)-2ν_4 and 2ν_5-(ν_5+ν_4) bands, have been measured in the 0.2-1.6 THz region, and 202 of them were observed for the first time. The precision of these measurements is estimated to be from 50 kHz to 100 kHz. A multistate analysis was carried out for the bending vibrational modes ν_4 and ν_5 of ^{12}C_2D_2, which includes the lines observed in this work and prior microwave, far-infrared and infrared data on the pure bending levels. Significantly improved molecular parameters were obtained for ^{12}C_2D_2 by adding the new measurements to the old data set which had only 10 lines with microwave measurement precision. The experiments on ^{12}C_2H_2 are in progress and ten P branch lines have been observed. We will present the ^{12}C_2H_2 results to date.

  16. Accidental Degeneracies in N dimensions for Potential Class αr 2d-2-βr d-2 via Asymptotic Iteration Method (AIM) (United States)

    Kisoglu, H. F.; Ciftci, Hakan


    In mathematical physics the main goal of quantum mechanics is to obtain the energy spectrum of an atomic system. In many practices, Schrödinger equation which is a second order and linear differential equation is solved to do this analysis. There are many theoretic mathematical methods serving this purpose. We use Asymptotic Iteration Method (AIM) to obtain the energy eigenvalues of Schrödinger equation in N-dimensional euclidean space for a potential class given as α {r}2d-2-β {r}d-2. We also obtain a restriction on the eigenvalues that gives degeneracies. Besides, we crosscheck the eigenvalues and degeneracies using the perturbation theory in the view of the AIM.

  17. Detection of phasic dopamine by D1 and D2 striatal medium spiny neurons. (United States)

    Yapo, Cedric; Nair, Anu G; Clement, Lorna; Castro, Liliana R; Hellgren Kotaleski, Jeanette; Vincent, Pierre


    Brief dopamine events are critical actors of reward-mediated learning in the striatum; the intracellular cAMP-protein kinase A (PKA) response of striatal medium spiny neurons to such events was studied dynamically using a combination of biosensor imaging in mouse brain slices and in silico simulations. Both D1 and D2 medium spiny neurons can sense brief dopamine transients in the sub-micromolar range. While dopamine transients profoundly change cAMP levels in both types of medium spiny neurons, the PKA-dependent phosphorylation level remains unaffected in D2 neurons. At the level of PKA-dependent phosphorylation, D2 unresponsiveness depends on protein phosphatase-1 (PP1) inhibition by DARPP-32. Simulations suggest that D2 medium spiny neurons could detect transient dips in dopamine level. The phasic release of dopamine in the striatum determines various aspects of reward and action selection, but the dynamics of the dopamine effect on intracellular signalling remains poorly understood. We used genetically encoded FRET biosensors in striatal brain slices to quantify the effect of transient dopamine on cAMP or PKA-dependent phosphorylation levels, and computational modelling to further explore the dynamics of this signalling pathway. Medium-sized spiny neurons (MSNs), which express either D 1 or D 2 dopamine receptors, responded to dopamine by an increase or a decrease in cAMP, respectively. Transient dopamine showed similar sub-micromolar efficacies on cAMP in both D1 and D2 MSNs, thus challenging the commonly accepted notion that dopamine efficacy is much higher on D 2 than on D 1 receptors. However, in D2 MSNs, the large decrease in cAMP level triggered by transient dopamine did not translate to a decrease in PKA-dependent phosphorylation level, owing to the efficient inhibition of protein phosphatase 1 by DARPP-32. Simulations further suggested that D2 MSNs can also operate in a 'tone-sensing' mode, allowing them to detect transient dips in basal dopamine

  18. Coupling between d-3-phosphoglycerate dehydrogenase and d-2-hydroxyglutarate dehydrogenase drives bacterial l-serine synthesis. (United States)

    Zhang, Wen; Zhang, Manman; Gao, Chao; Zhang, Yipeng; Ge, Yongsheng; Guo, Shiting; Guo, Xiaoting; Zhou, Zikang; Liu, Qiuyuan; Zhang, Yingxin; Ma, Cuiqing; Tao, Fei; Xu, Ping


    l-Serine biosynthesis, a crucial metabolic process in most domains of life, is initiated by d-3-phosphoglycerate (d-3-PG) dehydrogenation, a thermodynamically unfavorable reaction catalyzed by d-3-PG dehydrogenase (SerA). d-2-Hydroxyglutarate (d-2-HG) is traditionally viewed as an abnormal metabolite associated with cancer and neurometabolic disorders. Here, we reveal that bacterial anabolism and catabolism of d-2-HG are involved in l-serine biosynthesis in Pseudomonas stutzeri A1501 and Pseudomonas aeruginosa PAO1. SerA catalyzes the stereospecific reduction of 2-ketoglutarate (2-KG) to d-2-HG, responsible for the major production of d-2-HG in vivo. SerA combines the energetically favorable reaction of d-2-HG production to overcome the thermodynamic barrier of d-3-PG dehydrogenation. We identified a bacterial d-2-HG dehydrogenase (D2HGDH), a flavin adenine dinucleotide (FAD)-dependent enzyme, that converts d-2-HG back to 2-KG. Electron transfer flavoprotein (ETF) and ETF-ubiquinone oxidoreductase (ETFQO) are also essential in d-2-HG metabolism through their capacity to transfer electrons from D2HGDH. Furthermore, while the mutant with D2HGDH deletion displayed decreased growth, the defect was rescued by adding l-serine, suggesting that the D2HGDH is functionally tied to l-serine synthesis. Substantial flux flows through d-2-HG, being produced by SerA and removed by D2HGDH, ETF, and ETFQO, maintaining d-2-HG homeostasis. Overall, our results uncover that d-2-HG-mediated coupling between SerA and D2HGDH drives bacterial l-serine synthesis.

  19. Evidence That Sleep Deprivation Downregulates Dopamine D2R in Ventral Striatum in the Human Brain

    Energy Technology Data Exchange (ETDEWEB)

    Volkow N. D.; Fowler J.; Volkow, N.D.; Tomasi, D.; Wang, G.-J.; Fowler, J.S.; Logan, J.; Benveniste, H.; Kin, R.; Thanos, P.K.; Sergi F.


    Dopamine D2 receptors are involved with wakefulness, but their role in the decreased alertness associated with sleep deprivation is unclear. We had shown that sleep deprivation reduced dopamine D2/D3 receptor availability (measured with PET and [{sup 11}C]raclopride in controls) in striatum, but could not determine whether this reflected dopamine increases ([{sup 11}C]raclopride competes with dopamine for D2/D3 receptor binding) or receptor downregulation. To clarify this, we compared the dopamine increases induced by methylphenidate (a drug that increases dopamine by blocking dopamine transporters) during sleep deprivation versus rested sleep, with the assumption that methylphenidate's effects would be greater if, indeed, dopamine release was increased during sleep deprivation. We scanned 20 controls with [{sup 11}C]raclopride after rested sleep and after 1 night of sleep deprivation; both after placebo and after methylphenidate. We corroborated a decrease in D2/D3 receptor availability in the ventral striatum with sleep deprivation (compared with rested sleep) that was associated with reduced alertness and increased sleepiness. However, the dopamine increases induced by methylphenidate (measured as decreases in D2/D3 receptor availability compared with placebo) did not differ between rested sleep and sleep deprivation, and were associated with the increased alertness and reduced sleepiness when methylphenidate was administered after sleep deprivation. Similar findings were obtained by microdialysis in rodents subjected to 1 night of paradoxical sleep deprivation. These findings are consistent with a downregulation of D2/D3 receptors in ventral striatum with sleep deprivation that may contribute to the associated decreased wakefulness and also corroborate an enhancement of D2 receptor signaling in the arousing effects of methylphenidate in humans.

  20. Dopamine D2 receptor availability in opiate addicts at baseline and during naloxone precipitated withdrawal

    Energy Technology Data Exchange (ETDEWEB)

    Wang, G.J.; Volkow, N.D.; Logan, J. [Brookhaven National Lab., Upton, NY (United States)]|[SUNY, Stony Brook, NY (United States)]|[Psychiatry Services VAMC Northport, NY (United States)] [and others


    To determine if changes in dopamine activity contribute to the clinical presentation of opiate withdrawal we assessed dopamine (DA) D2 receptor availability in opiate-dependent subjects at baseline and during naloxone-precipitated withdrawal. DA D2 receptor availability was evaluated in eleven male heroine and methadone users using positron emission tomography (PET) and [11-C]raclopride and compared to eleven age matched male control subjects. Nine of the opiate-dependent subjects and two of the control were tested twice after placebo and naloxone (0.02 mg/kg) iv injection 7-10 min. prior to [11-C]raclopride. DA D2 receptor availability was measured using the ratio of the distribution volume in the region of interest (caudate, putamen and ventral striatum) to that in the cerebellum which is a function of B{sub max}/K{sub d}. DA D2 receptor availability in putamen was significantly lower in opiate-dependent subjects (3.44 {plus_minus} 0.4) than that in controls (3.97 {plus_minus} 0.45, p {ge} 0.009). Naloxone induced a short lasting withdrawal in all of the opiate-dependent subjects (79 {plus_minus} 17% of maximum withdrawal), but not in controls, with significant increase in pulse (p {le} 0.006), blood pressure (p {le} 0.0001), lacrimation (p {le} 0.01), muscle twitches (p {le} 0.01), annoyance (p {le} 0.005), anxiety (p {le} 0.0006), restlessness (p {le} 0.0005) and unhappiness (p {le} 0.001). DA D2 receptor availability in basal ganglia after naloxone administration was not different from that of baseline. These results document abnormalities in DA D2 receptors in opiate-dependent subjects. However, DA D2 availability did not change with naloxone-precipitated withdrawal.

  1. Bioavailability of vitamin D2 from enriched mushrooms in prediabetic adults: a randomized controlled trial. (United States)

    Mehrotra, A; Calvo, M S; Beelman, R B; Levy, E; Siuty, J; Kalaras, M D; Uribarri, J


    Based on the growing evidence of risk reduction from fresh fruit and vegetable consumption and an inverse relationship between serum 25-hydroxyvitamin D (25OHD) and the risk of type 2 diabetes (T2D), we determined the benefits of regularly consuming vitamin D-enriched mushrooms in a prediabetic cohort. Exposing edible mushrooms to ultraviolet B (UVB) light increases vitamin D2 (D2) and raises serum 25OHD2 in healthy young adults; however, their benefit to deficient prediabetics and glucose metabolism remains untested. Forty-three prediabetic, D-deficient adults (25OHD≤20 ng/ml), BMI>25 were randomized to four groups consuming daily entrées containing 100 g fresh sliced cooked mushrooms prepared by a chef for 16 weeks. Two groups were fed UVB-treated mushrooms initially containing: 600 IU D2 or 4000 IU D2; each one also received one capsule of placebo daily. Two control groups were fed untreated mushrooms and D3 dietary supplements at two label doses: 600 IU D3 and 4000 IU D3. D2 and D3 content were analyzed in mushrooms, before and after cooking and in over-the-counter supplements. After 16 weeks, both D2-UVB-mushroom entrée doses, which were significantly lower after cooking, produced modest or no increases in 25OHD2 or total 25OHD relative to the positive control subjects who actually consumed about 1242 and 7320 IU per day of D3 (higher than stated on the label). Unanticipated D2 cooking loss from fresh UVB mushrooms and probable low absorption and/or hydroxylation may explain the smaller increase in 25OHD2 in our prediabetic overweight/obese cohort compared with past findings in younger, healthy subjects. Moreover, no dose or vitamin D source was associated with modifying T2D risk factors.

  2. Threshold of Dopamine D2/3 Receptor Occupancy for Hyperprolactinemia in Older Patients With Schizophrenia. (United States)

    Iwata, Yusuke; Nakajima, Shinichiro; Caravaggio, Fernando; Suzuki, Takefumi; Uchida, Hiroyuki; Plitman, Eric; Chung, Jun Ku; Mar, Wanna; Gerretsen, Philip; Pollock, Bruce G; Mulsant, Benoit H; Rajji, Tarek K; Mamo, David C; Graff-Guerrero, Ariel


    Although hyperprolactinemia carries a long-term risk of morbidity, the threshold of dopamine D2/3 receptor (D2/3R) occupancy for hyperprolactinemia has not been investigated in older patients with schizophrenia. Data were taken from a positron emission tomography (PET) study conducted between August 2007 and August 2015. The present post hoc study included 42 clinically stable outpatients with schizophrenia (DSM-IV) (mean ± SD age = 60.2 ± 6.7 years) taking olanzapine or risperidone. Subjects underwent [¹¹C]-raclopride PET scans to measure D2/3R occupancy before and after reducing their dose of antipsychotic by up to 40%. Blood samples were collected before each PET scan to measure prolactin levels. The relationship between prolactin levels and D2/3R occupancy was examined using stepwise linear regression analyses. The D2/3R occupancy thresholds for hyperprolactinemia were explored using Fisher exact tests. Prolactin levels decreased following dose reduction (mean ± SD = 24.1 ± 30.2 ng/mL to 17.2 ± 15.1 ng/mL; P < .001). Prolactin levels were associated with female gender (β = .32, P = .006, vs male), antipsychotics (β = .23, P = .02, risperidone vs olanzapine), and D2/3R occupancy (β = .23, P = .04). Those with D2/3R occupancy of 66% or higher were more likely to have hyperprolactinemia than those with D2/3R occupancy lower than 66% (P = .03). Sensitivity, specificity, positive predictive value, and negative predictive value of this threshold were 0.44, 0.81, 0.78, and 0.48, respectively. We identified a D2/3R occupancy threshold for hyperprolactinemia of 66% in older patients with schizophrenia, which is lower than that reported in younger patients (73%) by other researchers. Our results suggest a higher sensitivity to antipsychotics in older patients. Prolactin levels could assist in the determination of appropriate antipsychotic dosing to minimize adverse effects. identifier: NCT00716755.

  3. Effect of D2O on growth properties and chemical structure of annual ryegrass (Lolium multiflorum)

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Barbara R [ORNL; Bali, Garima [Georgia Institute of Technology, Atlanta; Reeves, David T [ORNL; O' Neill, Hugh Michael [ORNL; Sun, Qining [Georgia Institute of Technology, Atlanta; Shah, Riddhi S [ORNL; Ragauskas, Arthur [Georgia Institute of Technology, Atlanta


    In present paper, we report the production and detailed structural analysis of deuterium-enriched rye grass (Lolium multiflorum) for neutron scattering experiments. An efficient method to produce deuterated biomass was developed by designing hydroponic perfusion chambers. In preliminary studies, the partial deuterated rye samples were grown in increasing levels of D2O to study the seed germination and the level of deuterium incorporation as a function of D2O concentration. Solution NMR method indicated 36.9 % deuterium incorporation in 50 % D2O grown annual rye samples and further significant increase in the deuterium incorporation level was observed by germinating the rye seedlings in H2O and growing in 50 % D2O inside the perfusion chambers. Moreover, in an effort to compare the substrate characteristics related to enzymatic hydrolysis on deuterated and protiated version of biomass, annual rye grown in 50 % D2O was selected for detailed biomass characterization studies. The compositional analyses, degree of polymerization and cellulose crystallinity were compared with its protiated control. The cellulose molecular weight indicated slight variation with deuteration; however, hemicellulose molecular weights and cellulose crystallinity remain unaffected with the deuteration. Besides the minor differences in biomass components, the development of deuterated biomass for neutron scattering application is essential to understand the complex biomass conversion processes.

  4. The infrared spectrum of the Ne-C2D2 complex (United States)

    Moazzen-Ahmadi, N.; McKellar, A. R. W.; Fernández, Berta; Farrelly, David


    Infrared spectra of Ne-C2D2 are observed in the region of the ν3 fundamental band (asymmetric C-D stretch, ≈2440 cm-1) using a tunable optical parametric oscillator to probe a pulsed supersonic slit jet expansion from a cooled nozzle. Like helium-acetylene, this system lies close to the free rotor limit, making analysis tricky because stronger transitions tend to pile up close to monomer (C2D2) rotation-vibration transitions. Assignments are aided by predicted rotational energies calculated from a published ab initio intermolecular potential energy surface. The analysis extends up to the j = 3←2 band, where j labels C2D2 rotation within the dimer, and is much more complete than the limited infrared assignments previously reported for Ne-C2H2 and Ne-C2HD. Two previous microwave transitions within the j = 1 state of Ne-C2D2 are reassigned. Coriolis model fits to the theoretical levels and to the spectrum are compared. Since the variations observed as a function of C2D2 vibrational excitation are comparable to those noted between theory and experiment, it is evident that more detailed testing of theory will require vibrational averaging over the acetylene intramolecular modes.

  5. Vitamin D2 supplementation amplifies eccentric exercise-induced muscle damage in NASCAR pit crew athletes. (United States)

    Nieman, David C; Gillitt, Nicholas D; Shanely, R Andrew; Dew, Dustin; Meaney, Mary Pat; Luo, Beibei


    This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day) had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD), and delayed onset of muscle soreness (DOMS) in National Association for Stock Car Auto Racing (NASCAR) NASCAR pit crew athletes. Subjects were randomized to vitD2 (n=13) and placebo (n=15), and ingested supplements (double-blind) for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test). Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OH)D2 456% and decreased 25(OH)D3 21% versus placebo (pNASCAR pit crew athletes following eccentric exercise.

  6. Dopamine D2 receptors preferentially regulate the development of light responses of the inner retina (United States)

    Tian, Ning; Xu, Hong-ping; Wang, Ping


    Retinal light responsiveness measured via electroretinography undergoes developmental modulation and is thought to be critically regulated by both visual experience and dopamine. The primary goal of this study is to determine whether the dopamine D2 receptor regulates the visual experience-dependent functional development of the retina. Accordingly, we recorded electroretinograms from wild type mice and mice with a genetic deletion of the gene that encodes the dopamine D2 receptor raised under normal cyclic light conditions and constant darkness. Our results demonstrate that mutation of the dopamine D2 receptors preferentially increases the amplitude of the inner retinal light responses evoked by high intensity light measured as oscillatory potentials in adult mice. During postnatal development, all three major components of electroretinograms, the a-wave, b-wave and oscillatory potentials, increase with age. Comparatively, mutation of the dopamine D2 receptors preferentially reduces the age-dependent increase of b-waves evoked by low intensity light. Light deprivation from birth reduces the amplitude of b-waves and completely diminishes the increased amplitude of oscillatory potentials. Taken together, these results demonstrate that the dopamine D2 receptor plays an important role in the activity-dependent functional development of the mouse retina. PMID:25393815

  7. Effects of vitamin D2-fortified bread v. supplementation with vitamin D2 or D3 on serum 25-hydroxyvitamin D metabolites: an 8-week randomised-controlled trial in young adult Finnish women

    DEFF Research Database (Denmark)

    Itkonen, Suvi T.; Skaffari, Essi; Saaristo, Pilvi


    There is a need for food-based solutions for preventing vitamin D deficiency. Vitamin D3 (D3) is mainly used in fortified food products, although the production of vitamin D2 (D2) is more cost-effective, and thus may hold opportunities. We investigated the bioavailability of D2 from UV-irradiated...

  8. Role of dopamine D2-like receptors within the ventral tegmental area and nucleus accumbens in antinociception induced by lateral hypothalamus stimulation. (United States)

    Moradi, Marzieh; Yazdanian, Mohamadreza; Haghparast, Abbas


    Several lines of evidence have shown that stimulation of the lateral hypothalamus (LH) can induce antinociception. It has been indicated that hypothalamic orexinergic neurons send projections throughout the dopamine mesolimbic pathway. Functional interaction between the LH and the main area of the mesolimbic pathway such as the ventral tegmental area (VTA) and the nucleus accumbens (NAc) implicates in pain modulation. Thus, in this study, we investigated the role of D2-like dopamine receptors within the VTA and NAc in the LH stimulation-induced antinociception. Male Wistar rats weighing 230-280 g were unilaterally implanted with two separate cannulae into the LH and VTA or NAc. Animals received intra-VTA (0.25, 1 and 4 μg/0.3 μl DMSO) and intra-accumbal (0.125, 0.25, 1 and 4 μg/0.5 μl DMSO) infusions of sulpiride as a selective D2-like receptor antagonist, prior to intra-LH carbachol (125 nM/rat) administration. In the tail-flick test, the antinociceptive effects were measured using a tail-flick algesiometer and represented as maximal possible effect (%MPE) within 5, 15, 30, 45 and 60 min after injections. Our results showed that intra-VTA and intra-accumbal sulpiride dose-dependently attenuated the LH stimulation-induced antinociception. However, the blockade of D2-like receptors within the NAc was more significant than that of the VTA. These findings show that D2-like dopamine receptors in these regions play an important role in the LH-mediated modulation of nociceptive information in the acute model of pain in the rats. It seems that this pain modulating system is more relevant to D2-like receptors in the nucleus accumbens. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. miR-340 inhibits glioblastoma cell proliferation by suppressing CDK6, cyclin-D1 and cyclin-D2

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xuesong; Gong, Xuhai [Department of Neurology, Daqing Oilfield General Hospital, Daqing, Heilongjiang 163001 (China); Chen, Jing [Department of Neurology, Daqing Longnan Hospital, Daqing, Heilongjiang, 163001 China (China); Zhang, Jinghui [Department of Cardiology, The Fourth Hospital of Harbin City, Harbin, Heilongjiang 150026 (China); Sun, Jiahang [Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086 (China); Guo, Mian, E-mail: [Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086 (China)


    Glioblastoma development is often associated with alteration in the activity and expression of cell cycle regulators, such as cyclin-dependent kinases (CKDs) and cyclins, resulting in aberrant cell proliferation. Recent studies have highlighted the pivotal roles of miRNAs in controlling the development and growth of glioblastoma. Here, we provide evidence for a function of miR-340 in the inhibition of glioblastoma cell proliferation. We found that miR-340 is downregulated in human glioblastoma tissue samples and several established glioblastoma cell lines. Proliferation and neurosphere formation assays revealed that miR-340 plays an oncosuppressive role in glioblastoma, and that its ectopic expression causes significant defect in glioblastoma cell growth. Further, using bioinformatics, luciferase assay and western blot, we found that miR-340 specifically targets the 3′UTRs of CDK6, cyclin-D1 and cyclin-D2, leading to the arrest of glioblastoma cells in the G0/G1 cell cycle phase. Confirming these results, we found that re-introducing CDK6, cyclin-D1 or cyclin-D2 expression partially, but significantly, rescues cells from the suppression of cell proliferation and cell cycle arrest mediated by miR-340. Collectively, our results demonstrate that miR-340 plays a tumor-suppressive role in glioblastoma and may be useful as a diagnostic biomarker and/or a therapeutic avenue for glioblastoma. - Highlights: • miR-340 is downregulated in glioblastoma samples and cell lines. • miR-340 inhibits glioblastoma cell proliferation. • miR-340 directly targets CDK6, cyclin-D1, and cyclin-D2. • miR-340 regulates glioblastoma cell proliferation via CDK6, cyclin-D1 and cyclin-D2.

  10. Couplings in D(2,1;α) superconformal mechanics from the SU(2) perspective

    Energy Technology Data Exchange (ETDEWEB)

    Galajinsky, Anton [Laboratory of Mathematical Physics, Tomsk Polytechnic University,Lenin Ave. 30, 634050 Tomsk (Russian Federation)


    Dynamical realizations of the most general N=4 superconformal group in one dimension D(2,1;α) are reconsidered from the perspective of the R-symmetry subgroup SU(2). It is shown that any realization of the R-symmetry subalgebra in some phase space can be extended to a representation of the Lie superalgebra corresponding to D(2,1;α). Novel couplings of arbitrary number of supermultiplets of the type (1,4,3) and (0,4,4) to a single supermultiplet of either the type (3,4,1), or (4,4,0) are constructed. D(2,1;α) superconformal mechanics describing superparticles propagating near the horizon of the extreme Reissner-Nordström-AdS-dS black hole in four and five dimensions is considered. The parameter α is linked to the cosmological constant.

  11. Satellite studies of N/D-2/ emission and ion chemistry in aurorae (United States)

    Rusch, D. W.; Gerard, J.-C.


    The incident particle flux ion and neutral composition data taken on the AE-D satellite have been used to investigate the quantal emission of N2(plus) at 4278 A, N(D-2) at 5200 A, and the ion chemistry in aurorae. The results of a time dependent auroral model have been compared to the data. The calculated 4278 A emission of N2(plus), the 5200 A emission of N(D-2), the densities of O2(plus), NO(plus), N2(plus), O(plus), and the electron density are generally in agreement with the measured values. These results are consistent with the branching ratios and quenching rates deduced from previous studies of the N(D-2) densities in the day-time, mid-latitude ionosphere. It is found that in an auroral arc, the measured atomic oxygen density is lower than predicted by the MSIS model.

  12. Imaging addiction: D2 receptors and dopamine signaling in the striatum as biomarkers for impulsivity (United States)

    Trifilieff, Pierre; Martinez, Diana


    Dependence to drugs of abuse is closely associated with impulsivity, or the propensity to choose a lower, but immediate, reward over a delayed, but more valuable outcome. Here, we review clinical and preclinical studies showing that striatal dopamine signaling and D2 receptor levels – which have been shown to be decreased in addiction - directly impact impulsivity, which is itself predictive of drug self-administration. Based on these studies, we propose that the alterations in D2 receptor binding and dopamine release seen in imaging studies of addiction constitute neurobiological markers of impulsivity. Recent studies in animals also show that higher striatal dopamine signaling at the D2 receptor is associated with a greater willingness to expend effort to reach goals, and we propose that this same relationship applies to humans, particularly with respect to recovery from addiction. PMID:23851257

  13. N =4 ℓ-conformal Galilei superalgebras inspired by D(2 , 1; α) supermultiplets (United States)

    Galajinsky, Anton; Krivonos, Sergey


    N = 4 supersymmetric extensions of the ℓ-conformal Galilei algebra are constructed by properly extending the Lie superalgebra associated with the most general N = 4 superconformal group in one dimension D(2 ,1; α). If the acceleration generators in the superalgebra form analogues of the irreducible (1 , 4 , 3)-, (2 , 4 , 2)-, (3 , 4 , 1)-, and (4 , 4 , 0)-supermultiplets of D(2 , 1; α), the parameter α turns out to be constrained by Jacobi identities. In contrast, if the tower of the acceleration generators resembles a component decomposition of a generic real superfield, which is a reducible representation of D(2 , 1; α), α remains arbitrary. An N = 4 ℓ-conformal Galilei superalgebra recently proposed in [Phys. Lett. B 771 (2017) 401] is shown to be a particular instance of a more general construction in this work.

  14. production lines

    Directory of Open Access Journals (Sweden)

    Jingshan Li


    Full Text Available In this work, serial production lines with finished goods buffers operating in the pull regime are considered. The machines are assumed to obey Bernoulli reliability model. The problem of satisfying customers demand is addressed. The level of demand satisfaction is quantified by the due-time performance (DTP, which is defined as the probability to ship to the customer a required number of parts during a fixed time interval. Within this scenario, the definitions of DTP bottlenecks are introduced and a method for their identification is developed.

  15. Blockchain-Empowered Fair Computational Resource Sharing System in the D2D Network

    Directory of Open Access Journals (Sweden)

    Zhen Hong


    Full Text Available Device-to-device (D2D communication is becoming an increasingly important technology in future networks with the climbing demand for local services. For instance, resource sharing in the D2D network features ubiquitous availability, flexibility, low latency and low cost. However, these features also bring along challenges when building a satisfactory resource sharing system in the D2D network. Specifically, user mobility is one of the top concerns for designing a cooperative D2D computational resource sharing system since mutual communication may not be stably available due to user mobility. A previous endeavour has demonstrated and proven how connectivity can be incorporated into cooperative task scheduling among users in the D2D network to effectively lower average task execution time. There are doubts about whether this type of task scheduling scheme, though effective, presents fairness among users. In other words, it can be unfair for users who contribute many computational resources while receiving little when in need. In this paper, we propose a novel blockchain-based credit system that can be incorporated into the connectivity-aware task scheduling scheme to enforce fairness among users in the D2D network. Users’ computational task cooperation will be recorded on the public blockchain ledger in the system as transactions, and each user’s credit balance can be easily accessible from the ledger. A supernode at the base station is responsible for scheduling cooperative computational tasks based on user mobility and user credit balance. We investigated the performance of the credit system, and simulation results showed that with a minor sacrifice of average task execution time, the level of fairness can obtain a major enhancement.

  16. Dopamine Synthesis Capacity is Associated with D2/3 Receptor Binding but Not Dopamine Release. (United States)

    Berry, Anne S; Shah, Vyoma D; Furman, Daniella J; White III, Robert L; Baker, Suzanne L; O'Neil, James P; Janabi, Mustafa; D'Esposito, Mark; Jagust, William J


    Positron Emission Tomography (PET) imaging allows the estimation of multiple aspects of dopamine function including dopamine synthesis capacity, dopamine release, and D2/3 receptor binding. Though dopaminergic dysregulation characterizes a number of neuropsychiatric disorders including schizophrenia and addiction, there has been relatively little investigation into the nature of relationships across dopamine markers within healthy individuals. Here we used PET imaging in 40 healthy adults to compare, within individuals, the estimates of dopamine synthesis capacity (Ki) using 6-[18F]fluoro-l-m-tyrosine ([18F]FMT; a substrate for aromatic amino acid decarboxylase), baseline D2/3 receptor-binding potential using [11C]raclopride (a weak competitive D2/3 receptor antagonist), and dopamine release using [11C]raclopride paired with oral methylphenidate administration. Methylphenidate increases synaptic dopamine by blocking the dopamine transporter. We estimated dopamine release by contrasting baseline D2/3 receptor binding and D2/3 receptor binding following methylphenidate. Analysis of relationships among the three measurements within striatal regions of interest revealed a positive correlation between [18F]FMT Ki and the baseline (placebo) [11C]raclopride measure, such that participants with greater synthesis capacity showed higher D2/3 receptor-binding potential. In contrast, there was no relationship between [18F]FMT and methylphenidate-induced [11C]raclopride displacement. These findings shed light on the nature of regulation between pre- and postsynaptic dopamine function in healthy adults, which may serve as a template from which to identify and describe alteration with disease.Neuropsychopharmacology advance online publication, 4 October 2017; doi:10.1038/npp.2017.180.

  17. Vitamin D2 Supplementation Amplifies Eccentric Exercise-Induced Muscle Damage in NASCAR Pit Crew Athletes

    Directory of Open Access Journals (Sweden)

    David C. Nieman


    Full Text Available This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD, and delayed onset of muscle soreness (DOMS in National Association for Stock Car Auto Racing (NASCAR NASCAR pit crew athletes. Subjects were randomized to vitD2 (n = 13 and placebo (n = 15, and ingested supplements (double-blind for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test. Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OHD2 456% and decreased 25(OHD3 21% versus placebo (p < 0.001, p = 0.036, respectively, with no influence on muscle function test scores. The post-study eccentric exercise bout induced EIMD and DOMS, with higher muscle damage biomarkers measured in vitD2 compared to placebo (myoglobin 252%, 122% increase, respectively, p = 0.001; creatine phosphokinase 24 h post-exercise, 169%, 32%, p < 0.001, with no differences for DOMS. In summary, 6-weeks vitD2 (3800 IU/day significantly increased 25(OHD2 and decreased 25(OHD3, had no effect on muscle function tests, and amplified muscle damage markers in NASCAR pit crew athletes following eccentric exercise.

  18. D2 receptor blockade by risperidone correlates with attention deficits in late-life schizophrenia. (United States)

    Uchida, Hiroyuki; Rajji, Tarek K; Mulsant, Benoit H; Kapur, Shitij; Pollock, Bruce G; Graff-Guerrero, Ariel; Menon, Mahesh; Mamo, David C


    The negative impact of antipsychotic drugs on attention is expected to be greater in late-life schizophrenia because of the age-related changes in the dopamine receptor reserve. The objective of this study was to examine the relationship between dopamine D2 receptor blockade by risperidone and the cognitive function in late-life schizophrenia. Subjects with schizophrenia or schizoaffective disorder aged 50 or older who were receiving risperidone completed a [C]raclopride positron emission tomography scan to measure D2-binding potential in the striatum. The D2 receptor blockade by risperidone was calculated using age-corrected measures from healthy individuals and region of interest analysis of dynamic positron emission tomography data coregistered to the subjects' magnetic resonance imaging scans. Cognitive function was assessed using a battery of neuropsychological tests that included the Dementia Rating Scale-2 (DRS). Eleven subjects (mean +/- SD age, 64 +/- 8 years) participated in this study. The mean +/- SD D2 receptor blockade was 69% +/- 14% (range, 34%-80%). The age-corrected score on the attention subscale in the DRS was negatively correlated with the D2 receptor blockade. The DRS attention subscale score was lower in the subjects who experienced 74.9% or higher D2 blockade (median value, corresponding to a daily risperidone dose of >3.0 mg) than in those who did not. Although a causal attribution cannot be made in light of the cross-sectional nature of this study, the results suggest the critical importance of identifying the lowest effective dose of antipsychotic drugs in older patients with schizophrenia.

  19. Interaction of the Agrobacterium tumefaciens virulence protein VirD2 with histones. (United States)

    Wolterink-van Loo, Suzanne; Escamilla Ayala, Abril A; Hooykaas, Paul J J; van Heusden, G Paul H


    Agrobacterium tumefaciens is a Gram-negative soil bacterium that genetically transforms plants and, under laboratory conditions, also transforms non-plant organisms, such as fungi and yeasts. During the transformation process a piece of ssDNA (T-strand) is transferred into the host cells via a type IV secretion system. The VirD2 relaxase protein, which is covalently attached at the 5' end of the T-strand through Tyr29, mediates nuclear entry as it contains a nuclear localization sequence. How the T-strand reaches the chromatin and becomes integrated in the chromosomal DNA is still far from clear. Here, we investigated whether VirD2 binds to histone proteins in the yeast Saccharomyces cerevisiae. Using immobilized GFP-VirD2 and in vitro synthesized His6-tagged S. cerevisiae proteins, interactions between VirD2 and the histones H2A, H2B, H3 and H4 were revealed. In vivo, these interactions were confirmed by bimolecular fluorescence complementation experiments. After co-cultivation of Agrobacterium strains expressing VirD2 tagged with a fragment of the yellow fluorescent protein analogue Venus with yeast strains expressing histone H2A or H2B tagged with the complementary part of Venus, fluorescence was detected in dot-shaped structures in the recipient yeast cells. The results indicated that VirD2 was transferred from Agrobacterium to yeast cells and that it interacted with histones in the host cell, and thus may help direct the T-DNA (transferred DNA) to the chromatin as a prelude to integration into the host chromosomal DNA. © 2015 The Authors.


    Directory of Open Access Journals (Sweden)

    Wilson Luiz da COSTA JUNIOR


    Full Text Available Context Whether adjuvant chemoradiotherapy may contribute to improve survival outcomes after D2-gastrectomy remains controvertial. Objective To explore the clinical utility of N-Ratio in selecting gastric cancer patients for adjuvant chemoradiotherapy after D2-gastrectomy. Methods A retrospective cohort study was carried out on gastric cancer patients who underwent D2-gastrectomy alone or D2-gastrectomy plus adjuvant chemoradiotherapy (INT-0116 protocol at the Hospital A. C. Camargo from September 1998 to December 2008. Statistical analysis were performed using multiple conventional methods, such as c-statistic, adjusted Cox's regression and stratified survival analysis. Results Our analysis involved 128 patients. According to c-statistic, the N-Ratio (i.e., as a continuous variable presented “area under ROC curve” (AUC of 0.713, while the number of metastatic nodes presented AUC of 0.705. After categorization, the cut-offs provide by Marchet et al. displayed the highest discriminating power – AUC value of 0.702. This N-Ratio categorization was confirmed as an independent predictor of survival using multivariate analyses. There also was a trend of better survival by adding of adjuvant chemoradiotherapy only for patients with milder degrees of lymphatic spread – 5-year survival of 23.1% vs 66.9%, respectively (HR = 0.426, 95% CI 0.150–1.202; P = 0.092. Conclusions This study confirms the N-Ratio as a tool to improve the lymph node metastasis staging in gastric cancer and suggests the cut-offs provided by Marchet et al. as the best way for its categorization after a D2-gastrectomy. In these settings, the N-Ratio appears a useful tool to select patients for adjuvant chemoradiotherapy, and the benefit of adding this type of adjuvancy to D2-gastrectomy is suggested to be limited to patients with milder degrees of lymphatic spread (i.e., NR2, 10%–25%.

  1. Genetic contributions to avoidance-based decisions: striatal D2 receptor polymorphisms. (United States)

    Frank, M J; Hutchison, K


    Individuals differ in their tendencies to seek positive decision outcomes or to avoid negative ones. At the neurobiological level, our model suggests that phasic changes in dopamine support learning to reinforce good decisions via striatal D1 receptors, and to avoid maladaptive choices via striatal D2 receptors. Accordingly, in a previous study individual differences in positive and negative learning were strongly modulated by two genetic polymorphisms factors related to striatal D1 and D2 function, respectively. Nevertheless, whereas the role for dopamine in positive learning is relatively well accepted, that in learning to avoid negative outcomes is more controversial. Here we further explore D2-receptor-related genetic contributions to probabilistic avoidance in humans, in light of recent data showing that particular DRD2 polymorphisms are associated with functional modulation of receptor expression [Zhang Y, Bertolino A, Fazio L, Blasi G, Rampino A, Romano R, Lee M-LT, Xiao T, Papp A, Wang D, Sadée W (2007) Polymorphisms in human dopamine d2 receptor gene affect gene expression, splicing, and neuronal activity during working memory. Proc Natl Acad Sci U S A 104(51):20552-20557]. We find that a promoter polymorphism rs12364283 associated with transcription and D2 receptor density was strongly and selectively predictive of avoidance-based decisions. Two further polymorphisms (rs2283265 and rs1076560) associated with relatively reduced presynaptic relative to postsynaptic D2 receptor expression were predictive of relative impairments in negative compared to positive decisions. These previously undocumented effects of DRD2 polymorphisms were largely independent of those we reported previously for the C957T polymorphism (rs6277) associated with striatal D2 density. In contrast, effects of the commonly studied Taq1A polymorphism on reinforcement-based decisions were due to indirect association with C957T. Taken together these findings suggest multiple D2-dependent

  2. Total synthesis of the endogenous inflammation resolving lipid resolvin D2 using a common lynchpin

    Directory of Open Access Journals (Sweden)

    John Li


    Full Text Available The total synthesis of the endogenous inflammation resolving eicosanoid resolvin D2 (1 is described. The key steps involved a Wittig reaction between aldehyde 5 and the ylide derived from phosphonium salt 6 to give enyne 17 and condensation of the same ylide with aldehyde 7 to afford enyne 11. Desilylation of 11 followed by hydrozirconation and iodination gave the vinyl iodide 4 and Sonogashira coupling between this compound and enyne 3 provided alkyne 18. Acetonide deprotection, partial reduction and ester hydrolysis then gave resolvin D2 (1.

  3. Fast Resource Scheduling in HetNets with D2D Support


    Limani Fazliu, Zana; Chiasserini, Carla Fabiana; Malandrino, Francesco; Casetti, Claudio Ettore


    Resource allocation in LTE networks is known to be an NP-hard problem. In this paper, we address an even more complex scenario: an LTE-based, 2-tier heterogeneous network where D2D mode is supported under the network control. All communications (macrocell, microcell and D2D-based) share the same frequency bands, hence they may interfere. We then determine (i) the network node that should serve each user and (ii) the radio resources to be scheduled for such communication. To this end, we devel...

  4. Collisional Dynamics of the Cesium D1 and D2 Transitions (United States)


    to the Faculty Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command in...2P 3 2 ] +M, (36) with rate coefficents k12 and k21 to be determined in this work. Third, population of the excited state may return to the ground... k12 [M ] A1 + (kQ1 + k21)[M ] (41) [ N2 N1 ] Pump D1 = ( ID2 ID1 )( d2 d1 ) = k21[M ] A2 + (kQ2 + k12 )[M ] . (42) when pumping the D2 and D1

  5. QSAR modeling on dopamine D2 receptor binding affinity of 6-methoxy benzamides. (United States)

    Samanta, Soma; Debnath, Bikash; Gayen, Shovanlal; Ghosh, Balaram; Basu, Anindya; Srikanth, Kolluru; Jha, Tarun


    QSAR modeling was performed on 58 (S) N-[(1-ethyl-2-pyrrolidinyl) methyl]-6-methoxy benzamides as dopamine (DA) D2 receptor antagonists to identify the structural requirements for DA D2 receptor binding affinity. The study pointed out that the presence of hydrophobic substituents at R3 position and electron-donating groups at R5 position increased the biological activity. Substitutions at phenyl ring favored the binding affinity of these benzamides. Ethyl group and iodine at R3 position were advantageous to the activity whereas nitro group at phenyl ring hindered the antagonistic activity.

  6. Reduced striatal dopamine D2 receptors in people with Internet addiction. (United States)

    Kim, Sang Hee; Baik, Sang-Hyun; Park, Chang Soo; Kim, Su Jin; Choi, Sung Won; Kim, Sang Eun


    An increasing amount of research has suggested that Internet addiction is associated with abnormalities in the dopaminergic brain system. We hypothesized that Internet addiction would be associated with reduced levels of dopaminergic receptor availability in the striatum compared with controls. To test this hypothesis, a radiolabeled ligand [C]raclopride and positron emission tomography was used to assess dopamine D2 receptor binding potential in men with and without Internet addiction. Consistent with our prediction, individuals with Internet addiction showed reduced levels of dopamine D2 receptor availability in subdivisions of the striatum including the bilateral dorsal caudate and right putamen. This finding contributes to the understanding of neurobiological mechanism of Internet addiction.

  7. Adolescent Maturation of Dopamine D1 and D2 Receptor Function and Interactions in Rodents (United States)

    Dwyer, Jennifer B.; Leslie, Frances M.


    Adolescence is a developmental period characterized by heightened vulnerability to illicit drug use and the onset of neuropsychiatric disorders. These clinical phenomena likely share common neurobiological substrates, as mesocorticolimbic dopamine systems actively mature during this period. Whereas prior studies have examined age-dependent changes in dopamine receptor binding, there have been fewer functional analyses. The aim of the present study was therefore to determine whether the functional consequences of D1 and D2-like activation are age-dependent. Adolescent and adult rats were given direct D1 and D2 agonists, alone and in combination. Locomotor and stereotypic behaviors were measured, and brains were collected for analysis of mRNA expression for the immediate early genes (IEGs), cfos and arc. Adolescents showed enhanced D2-like receptor control of locomotor and repetitive behaviors, which transitioned to dominant D1-like mechanisms in adulthood. When low doses of agonists were co-administered, adults showed supra-additive behavioral responses to D1/D2 combinations, whereas adolescents did not, which may suggest age differences in D1/D2 synergy. D1/D2-stimulated IEG expression was particularly prominent in the bed nucleus of the stria terminalis (BNST). Given the BNST’s function as an integrator of corticostriatal, hippocampal, and stress-related circuitry, and the importance of neural network dynamics in producing behavior, an exploratory functional network analysis of regional IEG expression was performed. This data-driven analysis demonstrated similar developmental trajectories as those described in humans and suggested that dopaminergic drugs alter forebrain coordinated gene expression age dependently. D1/D2 recruitment of stress nuclei into functional networks was associated with low behavioral output in adolescents. Network analysis presents a novel tool to assess pharmacological action, and highlights critical developmental changes in functional

  8. Dopamine D2 Receptor Occupancy as a Predictor of Catalepsy in Rats : A Pharmacokinetic-Pharmacodynamic Modeling Approach

    NARCIS (Netherlands)

    Johnson, Martin; Kozielska, Magdalena; Reddy, Venkatesh Pilla; Vermeulen, An; Barton, Hugh A.; Grimwood, Sarah; de Greef, Rik; Groothuis, Geny M. M.; Danhof, Meindert; Proost, Johannes H.


    Objectives Dopamine D-2 receptor occupancy (D2RO) is the major determinant of efficacy and safety in schizophrenia drug therapy. Excessive D2RO (>80%) is known to cause catalepsy (CAT) in rats and extrapyramidal side effects (EPS) in human. The objective of this study was to use pharmacokinetic and

  9. Pharmacology and Structural Analysis of Ligand Binding to the Orthosteric Site of Glutamate-Like GluD2 Receptors

    DEFF Research Database (Denmark)

    Kristensen, Anders S; Hansen, Kasper B; Naur, Peter


    -term depression. Here, we investigate the pharmacology of the orthosteric binding site in GluD2 by examining the activity of analogs of D-Ser and GluN1 glycine site competitive antagonists at GluD2 receptors containing the lurcher mutation (GluD2(LC)), which promotes spontaneous channel activation. We identify...

  10. Biosynthesis of the D2-cell adhesion molecule: post-translational modifications, intracellular transport, and developmental changes

    DEFF Research Database (Denmark)

    Lyles, J M; Linnemann, D; Bock, E


    Posttranslational modifications and intracellular transport of the D2-cell adhesion molecule (D2-CAM) were examined in cultured fetal rat neuronal cells. Developmental changes in biosynthesis were studied in rat forebrain explant cultures. Two D2-CAM polypeptides with Mr of 187,000-210,000 (A...

  11. Functional characterisation of eel dopamine D2 receptors and involvement in the direct inhibition of pituitary gonadotrophins

    DEFF Research Database (Denmark)

    Jolly, C.; Rousseau, K.; Prézeau, L.


    pharmacologically related to the D2 family. In the European eel, two distinct D2 receptor (D2‐R) paralogous genes have been identified (D2A‐R and D2B‐R) and both were shown to be expressed in the pituitary. We investigated the potential role of each paralogue in the control of gonadotroph function in this species....... Eel recombinant D2A‐R or D2B‐R were expressed in HEK 293 cells, with a universal Gα subunit, and receptor activation was followed by inositol phosphate production. Recombinant D2‐Rs exhibited a comparable affinity for DA, although they had differential affinities for mammalian D2‐R agonists...... and antagonists, supporting subtle structure/activity differences. Furthermore, using eel pituitary cell primary cultures, the expression by gonadotroph cells of both native eel D2‐R paralogues was examined by in situ hybridisation of D2A‐R or D2B‐R transcripts, coupled with immunofluorescence of luteinising...

  12. Involvement of dopamine D1/D5 and D2 receptors in context-dependent extinction learning and memory reinstatement

    Directory of Open Access Journals (Sweden)

    Marion Agnes Emma Andre


    Full Text Available Dopamine contributes to the regulation of higher order information processing and executive control. It is important for memory consolidation processes, and for the adaptation of learned responses based on experience. In line with this, under aversive learning conditions, application of dopamine receptor antagonists prior to extinction result in enhanced memory reinstatement. Here, we investigated the contribution of the dopaminergic system to extinction and memory reinstatement (renewal of an appetitive spatial learning task in rodents. Rats were trained for 3 days in a T-maze (context ‘A’ to associate a goal arm with a food reward, despite low reward probability (acquisition phase. On day 4, extinction learning (unrewarded occurred, that was reinforced by a context change (‘B’. On day 5, re-exposure to the (unrewarded ‘A’-context took place (renewal of context ‘A’, followed by extinction of context ‘A’. In control animals, significant extinction occurred on day 4, that was followed by an initial memory reinstatement (renewal on day 5, that was, in turn, succeeded by extinction of renewal. Intracerebral treatment with a D1/D5-receptor antagonist prior to the extinction trials, elicited a potent enhancement of extinction in context ‘B’. By contrast, a D1/D5-agonist impaired renewal in context ’A’. Extinction in the ‘A’ context on day 5 was unaffected by the D1/D5-ligands. Treatment with a D2-receptor antagonist prior to extinction had no overall effect on extinction in context ‘B or renewal in context ‘A’, although extinction of the renewal effect was impaired on day 5, compared to controls.Taken together, these data suggest that dopamine acting on the D1/D5-receptor modulates both acquisition and consolidation of context-dependent extinction. By contrast, the D2-receptor may contribute to context-independent aspects of this kind of extinction learning.


    Directory of Open Access Journals (Sweden)

    Miroslav Marinov


    Full Text Available Purpose of the study is to track in, the blood flow and the metabolism in 15 organs of experimental rats, which are subjected to severe physical strain, treated with protein hydrolyzate and vitamine C (Vit. C. The animals are divided into one control and 4 experimental groups. After 30 minutes of swimming they are treated with already used produces, methionine 75selenium and and after another 2 hours of swimming, with 86rubidium. After being euthanized with thiopental and an autopsied, the following organs are taken from the rats: pancreas, spleen, testicles, duodenum, a part of small intestine and colon, adrenals, kidneys, liver, lungs, heart, aorta, a piece of muscle, part of a brain and stomach. Percentage of the activity per gram of tissue is determined, of the total activity, of the two isotopes for every organ and them being compared. Physical strain deteriorates blood flow and reduces the accumulation of methionine 75selenium, while the treatment with the hydrolyzate and Vit. C has a beneficial effect in almost all organs.

  14. Penning-trap mass measurements of exotic rubidium and gold isotopes for a mean-field study of pairing and quadrupole correlations

    CERN Document Server

    Manea, Vladimir


    The most complex nuclei are situated between the magic and the mid-shell ones, in regions known for sudden changes of the trends of nuclear observables. These are the so-called shape-transition regions, where the nuclear paradigm changes from the vibrational liquid drop to the static rotor. With few exceptions, nuclei in these regions are radioactive, with half-lives dropping into the millisecond range. Complementing the information obtained from the low-lying excitation spectrum, nuclear binding energies and mean-square charge radii are among the observables most sensitive to these changes of nuclear structure. In the present work, a study of the shape- transition phenomenon is performed by measurements of radioactive nuclides produced by the ISOLDE facility at CERN. The masses of the neutron-rich rubidium isotopes $^{98-100}$Rb and of the neutron-deficient gold isotopes $^{180, 185, 188, 190, 191}$Au are determined using the Penning-trap mass spectrometer ISOLTRAP. The mass of $^{100}$Rb is determined for t...

  15. Trace analysis of doxylamine succinate in animal feed, human urine, and wastewater by GC using a rubidium-sensitized nitrogen detector

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, H.C. Jr.; Holder, C.L.; Bowman, M.C.


    Doxylamine succinate, a drug used as a sleep-inducing agent, an antihistamine, and in a therapeutic formulation taken by pregnant women as an antinauseant, was scheduled for toxicological evaluation as part of a structure activity relationship study, with rats and mice, because a deficiency of such data exists with regard to many antihistamines. Analytical chemical procedures that ensure proper concentration, homogeneity, and stability of the drug in dosed feed, as well as the safety of personnel and the environment, were prerequisites for the toxicological tests. GC methods using a rubidium-sensitized nitrogen detector were developed for analysis of doxylamine succinate in animal feed, human urine, and wastewater at levels as low as 1 ppm, 100 ppb, and 100 ppb, respectively. Sample extracts were cleaned up by liquid-liquid partitioning, followed by additional cleanup on a column of silica gel. Data are presented concerning the stability of the drug in animal feed, extraction efficiencies, and the use of the silica gel cleanup column to separate the caffeine interference from doxylamine in extracts of human urine. Partition values and ancillary data concerning analysis of the drug in feed, by HPLC at levels as low as 10 ppm, are also reported.

  16. The clinical significance of the tumor cell D2-40 immunoreactivity in non-small cell lung cancer. (United States)

    Kadota, Kyuichi; Huang, Cheng-Long; Liu, Dage; Nakashima, Nariyasu; Yokomise, Hiroyasu; Ueno, Masaki; Haba, Reiji


    A monoclonal antibody D2-40 has been widely used for tumor lymphangiogenesis and lymphatic vessel invasion (LVI) in human cancers. However, the clinical significance of the tumor cell D2-40 immunoreactivity has not been clearly understood. We evaluated the tumor cell D2-40 immunoreactivity in non-small cell lung cancer (NSCLC). One hundred and forty-seven NSCLC patients were investigated. Immunohistochemistry using D2-40 was performed to evaluate the tumor cell D2-40 immunoreactivity, micro-lymphatic vessel density (Micro-LVD) and LVI. The intratumoral microvessels density (MVD) was evaluated by the CD34-immunostaining, and tumor proliferation was evaluated by the Ki-67-immunostaining. The percentage of D2-40-positive tumor cells was significantly higher in squamous cell carcinomas than in adenocarcinomas (P<0.0001), and all D2-40-strong tumors were squamous cell carcinomas. The percentage of D2-40-strong tumors was significantly higher in moderately to poorly differentiated tumors than in well-differentiated tumors (P=0.0332). Furthermore, the Ki-67 proliferation index in D2-40-strong tumors was significantly the highest. However, the tumor cell D2-40 immunoreactivity was not associated with Micro-LVD, LVI, or MVD. Regarding the patient survival, the overall survival was significantly lower in patients with D2-40-strong tumors than in patients with D2-40-negative or D2-40-weak tumors (P=0.0005). Multivariate analyses also revealed the tumor cell D2-40 immunoreactivity to be a significant prognostic factor of poor prognosis for NSCLC patients (P=0.0007). The D2-40 immunostaining is useful to identify aggressive squamous cell carcinomas of the lung. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  17. Bidirectional allosteric interactions between cannabinoid receptor 1 (CB1) and dopamine receptor 2 long (D2L) heterotetramers. (United States)

    Bagher, Amina M; Laprairie, Robert B; Toguri, J Thomas; Kelly, Melanie E M; Denovan-Wright, Eileen M


    Type 1 cannabinoid (CB1) and dopamine 2 long form (D2L) receptors can physically interact to form heteromers that display unique pharmacology in vitro compared to homomeric complexes. Co-expression of CB1 and D2L and co-application of CB1 and D2 agonists increases cAMP levels while administration of either agonist alone decreases cAMP levels. To understand the observed co-agonist response, our first goal of the current study was to define the stoichiometry of CB1/D2L/Gα protein complexes. Using bioluminescence resonance energy transfer 2 (BRET(2)), we confirmed that, CB1 homodimers, D2L homodimers, and CB1/D2L heteromers are formed. By using sequential resonance energy transfer 2 (SRET(2)) combined with bimolecular fluorescence complementation (BiFC), we were able to demonstrate that CB1/D2L form heterotetramers consisting of CB1 and D2L homodimers. We demonstrated that CB1/D2L heterotetramers are coupled to at least two Gα proteins. The second aim of the study was to investigate allosteric effects of a D2L agonist (quinpirole) on CB1 receptor function and to investigate the effects of a CB1 agonist [arachidonyl-2-chloroethylamide (ACEA)] on D2L receptor function within CB1/D2L heterotetramers. Treating cells co-expressing CB1 and D2L with both ACEA and quinpirole switched CB1 and D2L receptor coupling and signaling from Gαi to Gαs proteins, enhanced β-arrestin1 recruitment and receptor co-internalization. The concept of bidirectional allosteric interaction within CB1/D2 heterotetramers has important implications for understanding the activity of receptor complexes in native tissues and under pathological conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Parallel Lines

    Directory of Open Access Journals (Sweden)

    James G. Worner


    Full Text Available James Worner is an Australian-based writer and scholar currently pursuing a PhD at the University of Technology Sydney. His research seeks to expose masculinities lost in the shadow of Australia’s Anzac hegemony while exploring new opportunities for contemporary historiography. He is the recipient of the Doctoral Scholarship in Historical Consciousness at the university’s Australian Centre of Public History and will be hosted by the University of Bologna during 2017 on a doctoral research writing scholarship.   ‘Parallel Lines’ is one of a collection of stories, The Shapes of Us, exploring liminal spaces of modern life: class, gender, sexuality, race, religion and education. It looks at lives, like lines, that do not meet but which travel in proximity, simultaneously attracted and repelled. James’ short stories have been published in various journals and anthologies.

  19. Structure and Properties of Burnished and Nitrided AISI D2 Tool Steel

    Directory of Open Access Journals (Sweden)

    Daniel TOBOŁA


    Full Text Available D2 belongs to traditional steels, frequently used in metalworking industry. Shot peening and nitriding are known to improve the wear resistance of D2. In this work we focus on processes of slide burnishing and industrial low temperature gas nitriding. The D2 steel specimens were first subjected to heat treatments (HT prescribed by the manufacturer, turning (T, then burnishing (B and nitriding (N. The reason for turning was achieving appropriate surface roughness. Deformation induced in slide burnishing can be better controlled then in shot peening because of deterministic nature of this process. Four different paths to prepare surfaces were employed: HT + T, HT + T + B, HT + T + N, HT + T + B + N. D2 steel is very sensitive to the final finishing, wear rates vary up to 300 %. Two of our procedures (HT + T + N and HT + T + B + N are much superior to the others. Moreover, in the HT + T + N case, apparently the surface fatigue scaling off takes place.DOI:

  20. Data of evolutionary structure change: 1BI9D-2BHPA [Confc[Archive

    Lifescience Database Archive (English)


  1. Predicting dopamine D2 receptor occupancy in humans using a physiology-based approach

    NARCIS (Netherlands)

    Johnson, Martin; Kozielska, Magdalena; Pilla Reddy, Venkatesh; Vermeulen, An; Barton, Hugh A.; Grimwood, Sarah; de Greef, Rik; Groothuis, Genoveva; Danhof, Meindert; Proost, Johannes


    Objectives: A hybrid physiology-based pharmacokinetic and pharmacodynamic model (PBPKPD) was used to predict the time course of dopamine receptor occupancy (D2RO) in human striatum following the administration of antipsychotic (AP) drugs, using in vitro and in silico information. Methods: A hybrid

  2. 26 CFR 1.411(d)-2 - Termination or partial termination; discontinuance of contributions. (United States)


    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Termination or partial termination... Bonus Plans, Etc. § 1.411(d)-2 Termination or partial termination; discontinuance of contributions. (a... such plan is not a qualified trust) unless the plan provides that— (i) Upon the termination or partial...

  3. 17 CFR 240.12d2-1 - Suspension of trading. (United States)


    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Suspension of trading. 240... Securities Exchange Act of 1934 Suspension of Trading, Withdrawal, and Striking from Listing and Registration § 240.12d2-1 Suspension of trading. (a) A national securities exchange may suspend from trading a...

  4. Time-resolved Imaging of H2 + (D2 +) Nuclear Wave Packets (United States)

    Ergler, Th.; Rudenko, A.; Feuerstein, B.; Zrost, K.; Schröter, C. D.; Moshammer, R.; Ullrich, J.

    The spatio-temporal evolution of H2 + (D2 +) nuclear wave packets is mapped using time-resolved Coulomb explosion imaging. We visualize the motion of both dissociating and bound parts of the wave packet, observe its dephasing and subsequent revivals. The reconstructed probability density of the wave packet is in good agreement with earlier theoretical predictions.

  5. Time-series analysis of vibrational nuclear wave-packet dynamics in D2+ (United States)

    Thumm, Uwe; Niederhausen, Thomas; Feuerstein, Bernold


    We discuss the extent to which measured time-dependent fragment kinetic energy release (KER) spectra and calculated nuclear probability densities can reveal (1) the transition frequencies between stationary vibrational states, (2) the nodal structure of stationary vibrational states, (3) the ground-state adiabatic electronic potential curve of the molecular ion, and (4) the progression of decoherence induced by random interactions with the environment. We illustrate our discussion with numerical simulations for the time-dependent nuclear motion of vibrational wave packets in the D2+ molecular ion caused by the ionization of its neutral D2 parent molecule with an intense pump laser pulse. Based on a harmonic time-series analysis, we suggest a general scheme for the full reconstruction, up to an overall phase factor, of the initial wave packets based on measured KER spectra. We apply this scheme in a numerical simulation for vibrational wave packets in D2+ molecular ions and show how this reconstruction allows the clear distinction between commonly assumed stationary vibrational state distributions of the molecular ion following the ionization of D2 .

  6. Evaluation of potential agonist radioligands for imaging dopamine D2/3 receptors

    NARCIS (Netherlands)

    van Wieringen, J.P.


    Imaging dopamine receptors with PET and SPECT can shed light on the nature of neuropsychiatric disorders which are characterized by disturbances in dopamine D2/3 receptor functioning. Agonist radioligands are considered superior to antagonists because they are more sensitive to detect dopamine

  7. The D1-D2 region of the large subunit ribosomal DNA as barcode for ciliates. (United States)

    Stoeck, T; Przybos, E; Dunthorn, M


    Ciliates are a major evolutionary lineage within the alveolates, which are distributed in nearly all habitats on our planet and are an essential component for ecosystem function, processes and stability. Accurate identification of these unicellular eukaryotes through, for example, microscopy or mating type reactions is reserved to few specialists. To satisfy the demand for a DNA barcode for ciliates, which meets the standard criteria for DNA barcodes defined by the Consortium for the Barcode of Life (CBOL), we here evaluated the D1-D2 region of the ribosomal DNA large subunit (LSU-rDNA). Primer universality for the phylum Ciliophora was tested in silico with available database sequences as well as in the laboratory with 73 ciliate species, which represented nine of 12 ciliate classes. Primers tested in this study were successful for all tested classes. To test the ability of the D1-D2 region to resolve conspecific and congeneric sequence divergence, 63 Paramecium strains were sampled from 24 mating species. The average conspecific D1-D2 variation was 0.18%, whereas congeneric sequence divergence averaged 4.83%. In pairwise genetic distance analyses, we identified a D1-D2 sequence divergence of barcode for ciliated protists. © 2013 John Wiley & Sons Ltd.

  8. Fluorescence metrology of silica sol–gels–The effect of D2O and ...

    Indian Academy of Sciences (India)

    ... over traditional techniques for nanometre metrology, such as small angle X-ray and neutron scattering and electron microscopy. In this paper we present silica particle growth dynamics in a hydrogel as detected by two near-infrared dyes, the effect of adding D2O on the hydrodynamic radius and the effect of salt addition.

  9. Cannabinoid-1 receptor antagonist rimonabant (SR141716) increases striatal dopamine D2 receptor availability

    NARCIS (Netherlands)

    Crunelle, Cleo L.; van de Giessen, Elsmarieke; Schulz, Sybille; Vanderschuren, Louk J. M. J.; de Bruin, Kora; van den Brink, Wim; Booij, Jan


    The cannabinoid 1 receptor antagonist rimonabant (SR141716) alters rewarding properties and intake of food and drugs. Additionally, striatal dopamine D2 receptor (DRD2) availability has been implicated in reward function. This study shows that chronic treatment of rats with rimonabant (1.0 and

  10. Writer's cramp: restoration of striatal D2-binding after successful biofeedback-based sensorimotor training.

    NARCIS (Netherlands)

    Berger, H.J.C.; Werf, S.P. van der; Horstink, C.A.; Cools, A.R.; Oyen, W.J.G.; Horstink, M.W.I.M.


    INTRODUCTION: Previous studies of writer's cramp have detected cerebral sensorimotor abnormalities in this disorder and, more specifically, a reduced striatal D2-binding as assessed by [(123)I]IBZM SPECT. However, empirical data were lacking about the influence of effective biofeedback-based

  11. Thermochemistry and accurate quantum reaction rate calculations for H2/HD/D2 + CH3

    NARCIS (Netherlands)

    Nyman, G.; Harrevelt, R. van; Manthe, U.


    Accurate quantum-mechanical results for thermodynamic data, cumulative reaction probabilities (for J = 0), thermal rate constants, and kinetic isotope effects for the three isotopic reactions H-2 + CH3 -> CH4 + H, HD + CH3 -> CH4 + D, and D-2 + CH3 -> CH3D + D are presented. The calculations are

  12. Five-body calculations of D-2 fragmentation by Xe19+ impact

    NARCIS (Netherlands)

    Feeler, CR; Olson, RE; DuBois, RD; Schlatholter, T; Hadjar, O; Hoekstra, R; Morgenstern, R; Schlathölter, Thomas

    A five-body classical trajectory Monte Carlo model has been developed to study fragmentation of diatomic molecules after double electron removal by highly charged ion impact. A systematic study of the final-state deuteron energy and momentum spectra has been conducted for Xe19+ + D-2 collisions at

  13. Cannabinoids Regulate Bcl-2 and Cyclin D2 Expression in Pancreatic β Cells.

    Directory of Open Access Journals (Sweden)

    Jihye Kim

    Full Text Available Recent reports have shown that cannabinoid 1 receptors (CB1Rs are expressed in pancreatic β cells, where they induce cell death and cell cycle arrest by directly inhibiting insulin receptor activation. Here, we report that CB1Rs regulate the expression of the anti-apoptotic protein Bcl-2 and cell cycle regulator cyclin D2 in pancreatic β cells. Treatment of MIN6 and βTC6 cells with a synthetic CB1R agonist, WIN55,212-2, led to a decrease in the expression of Bcl-2 and cyclin D2, in turn inducing cell cycle arrest in G0/G1 phase and caspase-3-dependent apoptosis. Additionally, genetic deletion and pharmacological blockade of CB1Rs after injury in mice led to increased levels of Bcl-2 and cyclin D2 in pancreatic β cells. These findings provide evidence for the involvement of Bcl-2 and cyclin D2 mediated by CB1Rs in the regulation of β-cell survival and growth, and will serve as a basis for developing new therapeutic interventions to enhance β-cell function and growth in diabetes.

  14. Dynamics of the dissociative electron attachment in H 2 O and D 2 O ...

    Indian Academy of Sciences (India)

    The dynamics of the formation and decay of negative ion resonance of A1 symmetry at 8.5 eV electron energy in the dissociative electron attachment (DEA) process in H2O and D2O are investigated using the velocity slice imaging technique. While the highest energy hydride ions formed by DEA show angular distributions ...

  15. New realizations of the supergroup D(2,1;α) in N=4 superconformal mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Fedoruk, S.; Ivanov, E. [Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna, Moscow Region (Russian Federation)


    We present new explicit realizations of the most general N=4,d=1 superconformal symmetry D(2,1;α) in the models of N=4 superconformal mechanics based on the reducible multiplets (1,4,3)⊕(0,4,4), (3,4,1)⊕(0,4,4) and (4,4,0)⊕(0,4,4). We start from the manifestly supersymmetric superfield actions for these systems and then descend to the relevant off- and on-shell component actions from which we derive the D(2,1;α) (super)charges by the Noether procedure. Some peculiarities of these realizations of D(2,1;α) are discussed. We also construct a new D(2,1;α) invariant system by joining the multiplets (3,4,1) and (4,4,0) in such a way that they interact with each other through an extra (0,4,4) multiplet. New fermionic conformal couplings appear as the result of elimination of the appropriate auxiliary fields.

  16. Comparative d2/d3 LSU–rDNA sequence study of some Iranian ...

    African Journals Online (AJOL)



    Nov 5, 2007 ... Key words: Tea, Pratylenchus loosi, D2/D3 LSU rDNA, sequencing, Iran. INTRODUCTION. The tea root lesion .... Original DNA sequence data were collected from 13 Iranian tea root lesion nematode isolates that verified by ..... from Pasture grass in central Florida. Nematology. 42: 159-172. Jaumot M ...

  17. Low level of dopaminergic D2 receptor binding in obsessive-compulsive disorder

    NARCIS (Netherlands)

    Denys, Damiaan; van der Wee, Nic; Janssen, Joost; de Geus, Femke; Westenberg, Herman G. M.


    BACKGROUND: Despite growing evidence for involvement of the dopaminergic system in obsessive-compulsive disorder (OCD), the functional anatomy of the dopaminergic system in the basal ganglia has been investigated sparsely. METHODS: Dopamine D(2) receptor binding was assessed in 10 medication-free

  18. Dose-Response Effect of Sunlight on Vitamin D2 Production in Agaricus bisporus Mushrooms

    DEFF Research Database (Denmark)

    Urbain, Paul; Jakobsen, Jette


    The dose response effect of UV-B irradiation from sunlight on vitamin D2 content of sliced Agaricus bisporus (white button mushroom) during the process of sun-drying was investigated.Real-time UV-B and UV-A data were obtained using a high-performance spectroradiometer. During the first hour...... of sunlight exposure, the vitamin D2 content of the mushrooms increased in a linear manner, with concentrations increasing from 0.1 μg/g up to 3.9 ± 0.8 μg/g dry weight (DW). At the subsequent two measurements one and 3 h later, respectively, a plateau was reached. Two hours of additional exposure triggered...... a significant decline in vitamin D2 content. After just 15 min of sun exposure and an UV-B dose of 0.13 J/cm(2), the vitamin D2 content increased significantly to 2.2 ± 0.5 μg/g DW (P mushrooms and comparable to levels found...

  19. Equilibration in the Kac Model Using the GTW Metric d_2 (United States)

    Tossounian, H.


    We use the Fourier based Gabetta-Toscani-Wennberg metric d_2 to study the rate of convergence to equilibrium for the Kac model in 1 dimension. We take the initial velocity distribution of the particles to be a Borel probability measure μ on R^n that is symmetric in all its variables, has mean ěc {0} and finite second moment. Let μ _t(dv) denote the Kac-evolved distribution at time t, and let R_μ be the angular average of μ . We give an upper bound to d_2(μ _t, R_μ ) of the form \\min { B e^{-4 λ _1/n+3t}, d_2(μ ,R_μ )} , where λ _1 = n+2/2(n-1) is the gap of the Kac model in L^2 and B depends only on the second moment of μ . We also construct a family of Schwartz probability densities f_0^{(n)}: R^n→ R with finite second moments that shows practically no decrease in d_2(f_0(t), R_{f_0}) for time at least 1/2λ with λ the rate of the Kac operator. We also present a propagation of chaos result for the partially thermostated Kac model in Tossounian and Vaidyanathan (J Math Phys 56(8):083301, 2015).

  20. De novo expression of dopamine D2 receptors on microglia after stroke.

    NARCIS (Netherlands)

    Huck, J.H.; Freyer, D.; Bottcher, C.; Mladinov, M.; Muselmann-Genschow, C.; Thielke, M.; Gladow, N.; Bloomquist, D.; Mergenthaler, P.; Priller, J.


    Dopamine is the predominant catecholamine in the brain and functions as a neurotransmitter. Dopamine is also a potent immune modulator. In this study, we have characterized the expression of dopamine receptors on murine microglia. We found that cultured primary microglia express dopamine D1, D2, D3,

  1. Coordinated Precoding for D2D Communications Underlay Uplink MIMO Cellular Networks

    Directory of Open Access Journals (Sweden)

    Bing Fang


    Full Text Available We study the coordinated precoding problem for device-to-device (D2D communications underlay multiple-input multiple-output (MIMO cellular networks. The system model considered here constitutes multiple D2D user pairs attempting to share the uplink radio resources of a cellular network. We first formulate the coordinated precoding problem for the D2D user pairs as a sum-rate maximization (SRM problem, which is subject to a total interference power constraint imposed to protect the base station (BS and individual transmit power budgets available for each D2D user pair. Since the formulated SRM problem is nonconvex in general, we reformulate it as a difference convex- (DC- type programming problem, which can be iteratively solved by employing the famous successive convex approximation (SCA method. Moreover, a proximal-point-based regularization approach is also pursued here to ensure the convergence of the proposed algorithm. Interestingly, the centralized precoding algorithm can also lend itself to a distributed implementation. By introducing a price-based interference management mechanism, we reformulate the coordinated precoding problem as a Stackelberg game. Then, a distributed precoding algorithm is developed based on the concept of Stackelberg equilibrium (SE. Finally, numerical simulations are also provided to demonstrate the proposed algorithms. Results show that our algorithms can converge fast to a satisfactory solution with guaranteed convergence.

  2. Isotopic effects in the interaction of O- with D2 and H2 at low temperatures (United States)

    Plašil, Radek; Tran, Thuy Dung; Roučka, Štěpán; Jusko, Pavol; Mulin, Dmytro; Zymak, Illia; Rednyk, Serhiy; Kovalenko, Artem; Dohnal, Petr; Glosík, Juraj; Houfek, Karel; Táborský, Jiří; Čížek, Martin


    The isotopic effects in reactions of O- ions with H2 and D2 have been studied experimentally using a cryogenic 22-pole radio-frequency ion trap. The rate coefficients for associative detachment leading to H2O +e- and to D2O +e- and for atom transfer reactions leading to formation of OH- and OD- ions were determined at temperatures ranging from 15 to 300 K. The measured temperature dependencies of the rate coefficients for both channels of reactions of O- with H2 and D2 are compared with the results of the classical trajectory Monte Carlo simulation of the O-+H2 and O-+D2 collisions using the newly calculated potential energy surfaces. The measured temperature dependencies of the reaction rate coefficients for associative detachment are in very good agreement with the calculated ones. Agreement between experimental and calculated temperature dependencies of the rate coefficients of atom transfer reactions is off at most by a factor of 3 and the isotope effect is reproduced.

  3. D2.1 Required information/knowledge provision services specification

    NARCIS (Netherlands)

    Afsarmanesh, H.; Korojelo, S.P.; Karakas, O.U.; Sargolzaei, M.


    The deliverable D2.1 focuses on identification and analysis of the information/knowledge related to complex products in GloNet, while aiming at the specification of a set of generic services for their provision to the stakeholders. Towards achieving this goal, a systematic process is defined and

  4. Data of evolutionary structure change: 1CZ7D-2REPA [Confc[Archive

    Lifescience Database Archive (English)


  5. The role of the prostaglandin D2 receptor, DP, in eosinophil trafficking

    DEFF Research Database (Denmark)

    Schratl, Petra; Royer, Julia F; Kostenis, Evi


    Prostaglandin (PG) D2 is a major mast cell product that acts via two receptors, the D-type prostanoid (DP) and the chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2) receptors. Whereas CRTH2 mediates the chemotaxis of eosinophils, basophils, and Th2 lymphocytes, the role...

  6. Thermal behavior of TAXN and TCDXM D2 collimator mask, Finite element studies

    CERN Document Server

    Sklariks, Stepans


    The objective of this project was to perform thermal loading simulations of TCDXM (D2 collimator mask) and TAXN so as to allow the preliminary evaluation of the suitability of the given parts for the upcoming high luminosity upgrade that is to be performed in LHC in the nearest future.

  7. On Secondary Electron Emission from Solid H2 and D2

    DEFF Research Database (Denmark)

    Schou, Jørgen; Sørensen, H.


    The emission of secondary electrons from solid hydrogen (H2 , D2, T2) is often considered to be of importance for the interaction between a fusion plasma and pellets of solid hydrogens. A set-up was therefore built for studies of interactions between energetic particles and solid hydrogens. Studies...... of secondary electron emission (SEE) from solid H2 and D2 were made for incidence of electrons up to 3 keV and for incidence of ions of hydrogen, deuterium, and helium up to 10 keV. The measurements were made for normal incidence, and in some cases also for oblique incidence. The SEE coefficients for solid H2...... is always 0.65-0.70 times that for solid D2. This difference is attributed to different losses to vibrational states in H2 and D2 for the low energy electrons. Measurements were also made on solid para-H2 with both electrons and hydrogen ions. There was no difference from the results for normal H2, which...

  8. Nonsequential double ionization of D2 molecules with intense 20-fs pulses

    DEFF Research Database (Denmark)

    Sakai, H.; Larsen, J.J.; Wendt-Larsen, I.


    The kinetic-energy distribution of D+ fragments obtained from the ionization of D2 molecules with intense 20-fs pulses includes a high-energy component extending up to ˜10 eV. These fragments are only present for linearly, or slightly elliptically, polarized light. Both the maximum kinetic...

  9. A comprehensive review on cold work of AISI D2 tool steel (United States)

    Abdul Rahim, Mohd Aidil Shah bin; Minhat, Mohamad bin; Hussein, Nur Izan Syahriah Binti; Salleh, Mohd Shukor bin


    As a common material in mould and die application, AISI D2 cold work tool steel has proven to be a promising chosen material in the industries. However, challenges remain in using AISI D2 through a modified version with a considerable progress having been made in recent years. This paper provides a critical review of the original as-cast AISI D2 cold work tool steel up to the modified version. The main purpose is to develop an understanding of current modified tool steel trend; the machinability of AISI D2 (drilling, milling, turning, grinding and EDM/WEDM; and the microstructure evolution and mechanical properties of these cold work tool steels due to the presence of alloy materials in the steel matrix. The doping of rare earth alloy element, new steel fabrication processes, significant process parameter in machinability and surface treatment shows that there have been few empirical investigations into these cold work tool steel alloys. This study has discovered that cold work tool steel will remain to be explored in order to survive in the steel industries.

  10. Voluminous D2 source for intense cold neutron beam production at the ESS

    DEFF Research Database (Denmark)

    Klinkby, Esben Bryndt; Batkov, K.; Mezei, F.


    the target for the complementary needs of certain fundamental physics experiments. To facilitate experiments depending on the total number of neutrons in a sizable beam, the option of a voluminous D2 moderator, in a large cross-section extraction guide is discussed and its neutronic performance is assessed....

  11. Underlay of low-rate machine-type D2D links on downlink cellular links

    DEFF Research Database (Denmark)

    Pratas, Nuno K.; Popovski, Petar


    Wireless cellular networks feature two emerging technological trends: direct Device-to-Device (D2D) communications and Machine-Type Communications (MTC). MTC devices (MTDs) pose new challenges to the cellular network, such as low transmission power and massive access that can lead to overload of ...

  12. Novel cases of D-2-hydroxyglutaric aciduria with IDH1 or IDH2 mosaic mutations identified by amplicon deep sequencing

    DEFF Research Database (Denmark)

    Nota, Benjamin; Hamilton, Eline M; Sie, Daoud


    Mosaic IDH1 mutations are described as the cause of metaphyseal chondromatosis with increased urinary excretion of D-2-hydroxyglutarate (MC-HGA), and mutations in IDH2 as the cause of D-2-hydroxyglutaric aciduria (D-2HGA) type II. Mosaicism for IDH2 mutations has not previously been reported...... as a cause of D-2HGA. Here we describe three cases: one MC-HGA case with IDH1 mosaic mutations, and two D-2HGA type II cases. In one D-2HGA case we identified mosaicism for an IDH2 mutation as the genetic cause of this disorder; the other D-2HGA case was caused by a heterozygous IDH2 mutation, while...

  13. Comparison of metabolism of vitamins D2 and D3 in children with nutritional rickets. (United States)

    Thacher, Tom D; Fischer, Philip R; Obadofin, Michael O; Levine, Michael A; Singh, Ravinder J; Pettifor, John M


    Children with calcium-deficiency rickets may have increased vitamin D requirements and respond differently to vitamin D(2) and vitamin D(3). Our objective was to compare the metabolism of vitamins D(2) and D(3) in rachitic and control children. We administered an oral single dose of vitamin D(2) or D(3) of 1.25 mg to 49 Nigerian children--28 with active rickets and 21 healthy controls. The primary outcome measure was the incremental change in vitamin D metabolites. Baseline serum 25-hydroxyvitamin D [25(OH)D] concentrations ranged from 7 to 24 and 15 to 34 ng/mL in rachitic and control children, respectively (p children with rickets (29 ± 17 and 25 ± 11 ng/mL, respectively) and in control children (33 ± 13 and 31 ± 16 ng/mL, respectively). 1,25(OH)(2)D rose significantly (p children with rickets. By contrast, control children had no significant increase in 1,25(OH)(2)D (19 ± 28 and 16 ± 38 pg/mL after vitamin D(2) and D(3) administration, respectively). We conclude that in the short term, vitamins D(2) and D(3) similarly increase serum 25(OH)D concentrations in rachitic and healthy children. A marked increase in 1,25(OH)(2)D in response to vitamin D distinguishes children with putative dietary calcium-deficiency rickets from healthy children, consistent with increased vitamin D requirements in children with calcium-deficiency rickets. © 2010 American Society for Bone and Mineral Research.

  14. Design and Validation of In-Source Atmospheric Pressure Photoionization Hydrogen/Deuterium Exchange Mass Spectrometry with Continuous Feeding of D2O (United States)

    Acter, Thamina; Lee, Seulgidaun; Cho, Eunji; Jung, Maeng-Joon; Kim, Sunghwan


    In this study, continuous in-source hydrogen/deuterium exchange (HDX) atmospheric pressure photoionization (APPI) mass spectrometry (MS) with continuous feeding of D2O was developed and validated. D2O was continuously fed using a capillary line placed on the center of a metal plate positioned between the UV lamp and nebulizer. The proposed system overcomes the limitations of previously reported APPI HDX-MS approaches where deuterated solvents were premixed with sample solutions before ionization. This is particularly important for APPI because solvent composition can greatly influence ionization efficiency as well as the solubility of analytes. The experimental parameters for APPI HDX-MS with continuous feeding of D2O were optimized, and the optimized conditions were applied for the analysis of nitrogen-, oxygen-, and sulfur-containing compounds. The developed method was also applied for the analysis of the polar fraction of a petroleum sample. Thus, the data presented in this study clearly show that the proposed HDX approach can serve as an effective analytical tool for the structural analysis of complex mixtures. [Figure not available: see fulltext.

  15. VT Digital Line Graph Miscellaneous Transmission Lines (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This datalayer is comprised of Miscellaineous Transmission Lines. Digital line graph (DLG) data are digital representations of cartographic...

  16. Appearance of D2O in sweat after oral and oral-intravenous rehydration in men. (United States)

    Emmanuel, Holly; Casa, Douglas J; Beasley, Kathleen N; Lee, Elaine C; McDermott, Brendon P; Yamamoto, Linda M; Armstrong, Lawrence E; Maresh, Carl M


    Intravenous (IV) rehydration is common in athletics, but its thermoregulatory benefits and ergogenicity have not been elucidated. Availability of orally ingested fluid is dependent on gastric emptying and intestinal absorption rate. Deuterium oxide (D2O) has been used to demonstrate that fluid ingested during exercise appears in sweat within 10 minutes. The purpose of this study was to determine the effect of concurrent IV rehydration on D2O appearance in sweat samples after per ora rehydration with D2O labeled fluid. We hypothesized that the combination method would not be superior to the oral method. Ten fit men (age 23 ± 4, VO2max 59.49 ± 4.09 L·min(-1)) underwent 20 hours of fluid restriction resulting in 1.95 ± 0.25% body weight loss before beginning treadmill exercise and cycling. Exercise was performed in an environmental chamber (35.6 ± 0.2° C, 35.0 ± 1.8% relative humidity) for 2 hours at 55% VO2max, and the participants exhibited a mean body weight deficit of 4.50 ± 0.04%. Thermoregulatory measures were recorded while subjects were rehydrated with oral (OR) or oral combined with intravenous (IVO) fluid traced with D2O. After 30 minutes of rehydration and 30 minutes of seated recovery, the subjects began treadmill exercise at 55-60% VO2max. Forehead sweat samples were collected 0, 5, 10, 20, and 75 minutes from the start of rehydration. The samples were analyzed for D2O via isotope ratio mass spectrometry. D2O did not appear in the sweat within 20 minutes of rehydration; however, it did appear during the subsequent exercise bout. There was no significant difference between rehydration modes. Plasma volume increases and decreased volume of orally ingested fluid did not significantly alter transit time from ingestion to appearance in excreted sweat. The IVO method does not appear to be superior to the traditional OR method of rehydration.

  17. Reliability of the Dynavision™ D2 for Assessing Reaction Time Performance

    Directory of Open Access Journals (Sweden)

    Adam J. Wells


    Full Text Available Recently, the Dynavision™ D2 Visuomotor Training Device (D2 has emerged as a tool in the assessment of reaction time (RT; however, information regarding the reliability of the D2 have been limited, and to date, reliability data have been limited to non- generalizable samples. Therefore, the purpose of this study was to establish intraclass correlation coefficients (ICC2,1 for the D2 that are generalizable across a population of recreationally active young adults. Forty-two recreationally active men and women (age: 23.41 ± 4.84 years; height: 1.72 ± 0.11 m; mass: 76.62 ± 18.26 Kg completed 6 trials for three RT tasks of increasing complexity. Each trial was separated by at least 48-hours. A repeated measures ANOVA was used to detect differences in performance across the six trials. Intraclass correlation coefficients (ICC2,1 standard error of measurement (SEM, and minimal differences (MD were used to determine the reliability of the D2 from the two sessions with the least significant difference score. Moderate to strong reliability was demonstrated for visual RT (ICC2,1: 0.84, SEM: 0.033, and reactive ability in both Mode A and Mode B tasks (Mode A hits: ICC2,1: 0.75, SEM: 5.44; Mode B hits: ICC2,1: 0.73, SEM: 8.57. Motor RT (ICC2,1: 0.63, SEM: 0.035s showed fair reliability, while average RT per hit for Modes A and B showed moderate reliability (ICC2,1: 0.68, SEM: 0.43 s and ICC2,1: 0.72, SEM: 0.03 s respectively. It appears that one familiarization trial is necessary for the choice reaction time (CRT task while three familiarization trials are necessary for reactive RT tasks. In conclusion, results indicate that the Dynavision™ D2 is a reliable device to assess neuromuscular reactivity given that an adequate practice is provided. The data presented are generalizable to a population of recreationally active young adults.

  18. Exploring personality traits related to dopamine D2/3 receptor availability in striatal subregions of humans. (United States)

    Caravaggio, Fernando; Fervaha, Gagan; Chung, Jun Ku; Gerretsen, Philip; Nakajima, Shinichiro; Plitman, Eric; Iwata, Yusuke; Wilson, Alan; Graff-Guerrero, Ariel


    While several studies have examined how particular personality traits are related to dopamine D2/3 receptor (D2/3R) availability in the striatum of humans, few studies have reported how multiple traits measured in the same persons are differentially related to D2/3R availability in different striatal sub-regions. We examined how personality traits measured with the Karolinska Scales of Personality are related to striatal D2/3R availability measured with [(11)C]-raclopride in 30 healthy humans. Based on previous the literature, five personality traits were hypothesized to be most likely related to D2/3R availability: impulsiveness, monotony avoidance, detachment, social desirability, and socialization. We found self-reported impulsiveness was negatively correlated with D2/3R availability in the ventral striatum and globus pallidus. After controlling for age and gender, monotony avoidance was also negatively correlated with D2/3R availability in the ventral striatum and globus pallidus. Socialization was positively correlated with D2/3R availability in the ventral striatum and putamen. After controlling for age and gender, the relationship between socialization and D2/3R availability in these regions survived correction for multiple comparisons (p-threshold=.003). Thus, within the same persons, different personality traits are differentially related to in vivo D2/3R availability in different striatal sub-regions. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

  19. Exploring peronality traits related to dopamine D2/3 receptor availability in striatal subregions of humans (United States)

    Caravaggio, Fernando; Fervaha, Gagan; Chung, Jun Ku; Gerretsen, Philip; Nakajima, Shinichiro; Plitman, Eric; Iwata, Yusuke; Wilson, Alan; Graff-Guerrero, Ariel


    While several studies have examined how particular personality traits are related to dopamine D2/3 receptor (D2/3R) availability in the striatum of humans, few studies have reported how multiple traits measured in the same persons are differentially related to D2/3R availability in different striatal sub-regions. We examined how personality traits measured with the Karolinska Scales of Personality are related to striatal D2/3R availability measured with [11C]-raclopride in 30 healthy humans. Based on previous literature, five personality traits were hypothesized to be most likely related to D2/3R availability: impulsiveness, monotony avoidance, detachment, social desirability, and socialization. We found self-reported impulsiveness was negatively correlated with D2/3R availability in the ventral striatum and globus pallidus. After controlling for age and gender, monotony avoidance was also negatively correlated with D2/3R availability in the ventral striatum and globus pallidus. Socialization was positively correlated with D2/3R availability in the ventral striatum and putamen. After controlling for age and gender, the relationship between socialization and D2/3R availability in these regions survived correction for multiple comparisons (p-threshold=.003). Thus, within the same persons, different personality traits are differentially related to in vivo D2/3R availability in different striatal sub-regions. PMID:26944295

  20. Observing and preventing rubidium runaway in a direct-infusion xenon-spin hyperpolarizer optimized for high-resolution hyper-CEST (chemical exchange saturation transfer using hyperpolarized nuclei) NMR. (United States)

    Witte, C; Kunth, M; Rossella, F; Schröder, L


    Xenon is well known to undergo host-guest interactions with proteins and synthetic molecules. As xenon can also be hyperpolarized by spin exchange optical pumping, allowing the investigation of highly dilute systems, it makes an ideal nuclear magnetic resonance probe for such host molecules. The utility of xenon as a probe can be further improved using Chemical Exchange Saturation Transfer using hyperpolarized nuclei (Hyper-CEST), but for highly accurate experiments requires a polarizer and xenon infusion system optimized for such measurements. We present the design of a hyperpolarizer and xenon infusion system specifically designed to meet the requirements of Hyper-CEST measurements. One key element of this design is preventing rubidium runaway, a chain reaction induced by laser heating that prevents efficient utilization of high photon densities. Using thermocouples positioned along the pumping cell we identify the sources of heating and conditions for rubidium runaway to occur. We then demonstrate the effectiveness of actively cooling the optical cell to prevent rubidium runaway in a compact setup. This results in a 2-3-fold higher polarization than without cooling, allowing us to achieve a polarization of 25% at continuous flow rates of 9 ml/min of (129)Xe. The simplicity of this design also allows it to be retrofitted to many existing polarizers. Combined with a direction infusion system that reduces shot-to-shot noise down to 0.56% we have captured Hyper-CEST spectra in unprecedented detail, allowing us to completely resolve peaks separated by just 1.62 ppm. Due to its high polarization and excellent stability, our design allows the comparison of underlying theories of host-guest systems with experiment at low concentrations, something extremely difficult with previous polarizers.

  1. Fatores prognósticos nas gastrectomias com linfadenectomia D2 por adenocarcinoma gástrico Prognostic factors in D2 gastrectomy for gastric adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Osvaldo Antonio Prado Castro


    Full Text Available RACIONAL: A disseminação linfática é significativamente mais prevalente do que a hematogênica no câncer gástrico e assim torna-se importante o tratamento loco-regional, ou seja, a ressecção cirúrgica associada à linfadenectomia, preferencialmente do tipo D2. OBJETIVO: Avaliar a sobrevivência global nos pacientes submetidos à gastrectomia D2 por adenocarcinoma gástrico; determinar os principais fatores prognósticos e definir variáveis que possuam valor prognóstico independente. MÉTODOS: Estudo prospectivo em 125 pacientes submetidos à gastrectomia D2, entre agosto de 1997 e outubro de 2005. A técnica adotada seguiu rigorosamente o protocolo proposto pelo Centro Nacional de Câncer de Tóquio. RESULTADOS: Havia 73 homens e 52 mulheres com idades que variaram de 28 a 84 anos (média de 58,96 ± 14,01. Setenta por cento das lesões situavam-se na porção distal do estômago, 20% eram proximais e 10% ocupavam os três segmentos anatômicos do órgão. Os estádios estavam assim distribuídos: I - 37 casos (29,6%, II - 20 casos (16%, III - 37 casos (29,6%, e IV - 31 casos (24,8%. Realizou-se 87 gastrectomias subtotais e 38 totais. A morbidade total foi de 26,4%, constituindo-se predominantemente de fístulas e complicações pulmonares. A letalidade foi de 9,6%. Após seguimento médio de 48 meses, 68 (54,4% pacientes tinham falecido, representando sobrevivência global de 45,6%. As análises univariada e multivariada revelaram que: tumores que acometiam grandes segmentos do estômago, lesões que acometiam além da serosa (T3 ou T4, comprometimento neoplásico em mais de sete linfonodos (N2 ou N3, presença de metástases à distância (M1 e o estádio III e IV da doença, estavam relacionados diretamente com pior prognóstico. CONCLUSÃO: Menos da metade dos pacientes encontrava-se vivo após seguimento médio de quatro anos; o estádio TNM isolado constituiu-se no principal fator prognóstico, sendo que a extensão do

  2. Sieving of H2 and D2 Through End-to-End Nanotubes (United States)

    Devagnik, Dasgupta; Debra, J. Searles; Lamberto, Rondoni; Stefano, Bernardi


    We study the quantum molecular sieving of H2 and D2 through two nanotubes placed end-to-end. An analytic treatment, assuming that the particles have classical motion along the axis of the nanotube and are confined in a potential well in the radial direction, is considered. Using this idealistic model, and under certain conditions, it is found that this device can act as a complete sieve, allowing chemically pure deuterium to be isolated from an isotope mixture. We also consider a more realistic model of two carbon nanotubes and carry out molecular dynamics simulations using a Feynman—Hibbs potential to model the quantum effects on the dynamics of H2 and D2. Sieving is also observed in this case, but is caused by a different process.

  3. Achieving energy efficiency in LTE with joint D2D communications and green networking techniques

    KAUST Repository

    Yaacoub, Elias E.


    In this paper, the joint operation of cooperative device-to-device (D2D) communications and green cellular communications is investigated. An efficient approach for grouping mobile terminals (MTs) into cooperative clusters is described. In each cluster, MTs cooperate via D2D communications to share content of common interest. Furthermore, an energy-efficient technique for putting BSs in sleep mode in an LTE cellular network is presented. Finally, both methods are combined in order to ensure green communications for both the users\\' MTs and the operator\\'s BSs. The studied methods are investigated in the framework of OFDMA-based state-of-the-art LTE cellular networks, while taking into account intercell interference and resource allocation. © 2013 IEEE.

  4. Secondary electron emission from solid HD and a solid H2-D2 mixture

    DEFF Research Database (Denmark)

    Sørensen, H.; Børgesen, P.; Hao-Ming, Chen


    Secondary electron emission from solid HD and a solid 0.6 H2 + 0.4 D2 mixture has been studied for electron and hydrogen ion bombardment at primary energies from 0.5 to 3 keV and 2 to 10 keV/amu, respectively. The yield for solid HD is well explained by a simple stoichiometric model of the low......-energy stopping power for the internal secondaries. The secondary electron yield from the mixture is somewhat larger than the expected value, but lies between the values for pure solid H2 and D2. The secondary electron emission coefficient for solid tritium may be determined from a linear extrapolation...... of the present data....

  5. Does prostaglandin D2 hold the cure to male pattern baldness? (United States)

    Nieves, Ashley; Garza, Luis A


    Lipids in the skin are the most diverse in the entire human body. Their bioactivity in health and disease is underexplored. Prostaglandin D2 has recently been identified as a factor which is elevated in the bald scalp of men with androgenetic alopecia (AGA) and has the capacity to decrease hair lengthening. An enzyme which synthesizes it, prostaglandin D2 synthase (PTGDS or lipocalin-PGDS), is hormone responsive in multiple other organs. PGD2 has two known receptors, GPR44 and PTGDR. GPR44 was found to be necessary for the decrease in hair growth by PGD2 . This creates an exciting opportunity to perhaps create novel treatments for AGA, which inhibit the activity of PTGDS, PGD2 or GPR44. This review discusses the current knowledge surrounding PGD2 , and future steps needed to translate these findings into novel therapies for patients with AGA. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Statistical Modeling of Zr/Hf Extraction using TBP-D2EHPA Mixtures (United States)

    Rezaeinejhad Jirandehi, Vahid; Haghshenas Fatmehsari, Davoud; Firoozi, Sadegh; Taghizadeh, Mohammad; Keshavarz Alamdari, Eskandar


    In the present work, response surface methodology was employed for the study and prediction of Zr/Hf extraction curves in a solvent extraction system using D2EHPA-TBP mixtures. The effect of change in the levels of temperature, nitric acid concentration, and TBP/D2EHPA ratio (T/D) on the Zr/Hf extraction/separation was studied by the use of central composite design. The results showed a statistically significant effect of T/D, nitric acid concentration, and temperature on the extraction percentage of Zr and Hf. In the case of Zr, a statistically significant interaction was found between T/D and nitric acid, whereas for Hf, both interactive terms between temperature and T/D and nitric acid were significant. Additionally, the extraction curves were profitably predicted applying the developed statistical regression equations; this approach is faster and more economical compared with experimentally obtained curves.

  7. Mapping of Coherent Nuclear Wave Packet Dynamics in D_2^+ with Ultrashort Laser Pulses (United States)

    Feuerstein, Bernold; Thumm, Uwe


    Fast ionization of D2 leads to the coherent population of many vibrational states of D_2^+. Usually, only the squared absolute values of the vibrational state amplitudes, known as Franck-Condon factors, are observed since insufficient experimental time resolution averages out all coherence effects. We propose a Coulomb explosion imaging method to visualize the coherent motion of bound wave packets using ultrashort (5 fs), intense pump-probe laser pulses. With this type of experiment, decoherence times in the fs to ps range could be directly measured, providing essential information for coherent control. Supported in part by NSF (grant PHY-0071035) and Division of Chemical Sciences, Office of Basic Energy Scienes, Office of Energy Research, US DOE.

  8. Reliability of the dynavision™ d2 for assessing reaction time performance. (United States)

    Wells, Adam J; Hoffman, Jay R; Beyer, Kyle S; Jajtner, Adam R; Gonzalez, Adam M; Townsend, Jeremy R; Mangine, Gerald T; Robinson, Edward H; McCormack, William P; Fragala, Maren S; Stout, Jeffrey R


    Recently, the Dynavision™ D2 Visuomotor Training Device (D2) has emerged as a tool in the assessment of reaction time (RT); however, information regarding the reliability of the D2 have been limited, and to date, reliability data have been limited to non- generalizable samples. Therefore, the purpose of this study was to establish intraclass correlation coefficients (ICC2,1) for the D2 that are generalizable across a population of recreationally active young adults. Forty-two recreationally active men and women (age: 23.41 ± 4.84 years; height: 1.72 ± 0.11 m; mass: 76.62 ± 18.26 Kg) completed 6 trials for three RT tasks of increasing complexity. Each trial was separated by at least 48-hours. A repeated measures ANOVA was used to detect differences in performance across the six trials. Intraclass correlation coefficients (ICC2,1) standard error of measurement (SEM), and minimal differences (MD) were used to determine the reliability of the D2 from the two sessions with the least significant difference score. Moderate to strong reliability was demonstrated for visual RT (ICC2,1: 0.84, SEM: 0.033), and reactive ability in both Mode A and Mode B tasks (Mode A hits: ICC2,1: 0.75, SEM: 5.44; Mode B hits: ICC2,1: 0.73, SEM: 8.57). Motor RT (ICC2,1: 0.63, SEM: 0.035s) showed fair reliability, while average RT per hit for Modes A and B showed moderate reliability (ICC2,1: 0.68, SEM: 0.43 s and ICC2,1: 0.72, SEM: 0.03 s respectively). It appears that one familiarization trial is necessary for the choice reaction time (CRT) task while three familiarization trials are necessary for reactive RT tasks. In conclusion, results indicate that the Dynavision™ D2 is a reliable device to assess neuromuscular reactivity given that an adequate practice is provided. The data presented are generalizable to a population of recreationally active young adults. Key PointsThe Dynavision™ D2 is a light-training reaction device, developed to train sensory motor integration through the

  9. PRECO-D2: program for calculating preequilibrium and direct reaction double differential cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Kalbach, C.


    The code PRECO-D2 uses the exciton model for preequilibrium nuclear reactions to describe the emission of particles with mass numbers of 1 to 4 from an equilibrating composite nucleus. A distinction is made between open and closed configurations in this system and between the multi-step direct (MSD) and multi-step compound (MSC) components of the preequilibrium cross section. Additional MSD components are calculated semi-empirically to account for direct nucleon transfer reactions and direct knockout processes involving cluster degrees of freedom. Evaporation from the equilibrated composite nucleus is included in the full MSC cross section. Output of energy differential and double differential cross sections is provided for the first particle emitted from the composite system. Multiple particle emission is not considered. This report describes the reaction models used in writing PRECO-D2 and explains the organization and utilization of the code. 21 refs.

  10. M2 to D2 and vice versa by 3-Lie and Lie bialgebra

    Energy Technology Data Exchange (ETDEWEB)

    Aali-Javanangrouh, M.; Rezaei-Aghdam, A. [Azarbaijan Shahid Madani University, Department of Physics, Faculty of Science, Tabriz (Iran, Islamic Republic of)


    Using the concept of a 3-Lie bialgebra, which has recently been defined in arXiv:1604.04475, we construct a Bagger-Lambert-Gustavson (BLG) model for the M2-brane on a Manin triple of a special 3-Lie bialgebra. Then by using the correspondence and the relation between those 3-Lie bialgebra with Lie bialgebra, we reduce this model to an N = (4,4) WZW model (D2-brane), such that its algebraic structure is a Lie bialgebra with one 2-cocycle. In this manner by using the correspondence of the 3-Lie bialgebra and Lie bialgebra (for this special 3-Lie algebra) one can construct the M2-brane from a D2-brane and vice versa. (orig.)

  11. Magnetic field decoupling and 3D-2D crossover in Nb/Cu multilayers

    DEFF Research Database (Denmark)

    Krasnov, V.M.; Kovalev, A.E.; Oboznov, V.A.


    Transport properties of Nb/Cu multilayers were measured along and across layers. Ir is shown that not only the temperature but also the magnetic field parallel to layers can effectively decouple layers and cause the three-to-two-dimensional (3D-2D) crossover. As a consequence of the 3D-2D crossover......, sharpening of the resistive transition with current along layers occurs due to the appearance of a strong intrinsic pinning in the 2D state. Evidence for the intrinsic Josephson effect in the 2D state is provided both by the pei-iodic modulation of the dynamic resistance across layers versus the parallel...... magnetic field and by the multiply branched I-V curves caused by flux-flow of Josephson vortices in the stacked superconductor-normal-metal-superconductor junctions composing the multilayer. By measurements across layers the ''breaking field'' at which the proximity induced superconductivity in the normal...

  12. Longitudinal relaxation of ND4D2PO4 type antiferroelectrics. Piezoelectric resonance and sound attenuation

    Directory of Open Access Journals (Sweden)

    R.R. Levitskii


    Full Text Available Within the framework of the modified proton model with taking into account the interaction with the shear strain ε6, a dynamic dielectric response of ND4D2PO4 type antiferroelectrics is considered. Dynamics of the piezoelectric strain is taken into account. Experimentally observed phenomena of crystal clamping by high frequency electric field, piezoelectric resonance and microwave dispersion are described. Ultrasound velocity and attenuation are calculated. Character of behaviour of attenuation in the paraelectric phase and the existence of a cut-off frequency in the frequency dependence of attenuation are predicted. At the proper choice of the parameters, a good quantitative description of experimental data for longitudinal static dielectric, piezoelectric and elastic characteristics and sound velocity for ND4D2PO4 and NH4H2PO4 is obtained in the paraelectric phase.

  13. Dopamine signaling in food addiction: role of dopamine D2 receptors. (United States)

    Baik, Ja-Hyun


    Dopamine (DA) regulates emotional and motivational behavior through the mesolimbic dopaminergic pathway. Changes in DA signaling in mesolimbic neurotransmission are widely believed to modify reward-related behaviors and are therefore closely associated with drug addiction. Recent evidence now suggests that as with drug addiction, obesity with compulsive eating behaviors involves reward circuitry of the brain, particularly the circuitry involving dopaminergic neural substrates. Increasing amounts of data from human imaging studies, together with genetic analysis, have demonstrated that obese people and drug addicts tend to show altered expression of DA D2 receptors in specific brain areas, and that similar brain areas are activated by food-related and drug-related cues. This review focuses on the functions of the DA system, with specific focus on the physiological interpretation and the role of DA D2 receptor signaling in food addiction.

  14. Therapeutic window of dopamine D2/3 receptor occupancy to treat psychosis in Alzheimer's disease. (United States)

    Reeves, Suzanne; McLachlan, Emma; Bertrand, Julie; Antonio, Fabrizia D; Brownings, Stuart; Nair, Akshay; Greaves, Suki; Smith, Alan; Taylor, David; Dunn, Joel; Marsden, Paul; Kessler, Robert; Howard, Robert


    See Caravaggio and Graff-Guerrero (doi:10.1093/awx023) for a scientific commentary on this article.Antipsychotic drugs, originally developed to treat schizophrenia, are used to treat psychosis, agitation and aggression in Alzheimer's disease. In the absence of dopamine D2/3 receptor occupancy data to inform antipsychotic prescribing for psychosis in Alzheimer's disease, the mechanisms underpinning antipsychotic efficacy and side effects are poorly understood. This study used a population approach to investigate the relationship between amisulpride blood concentration and central D2/3 occupancy in older people with Alzheimer's disease by combining: (i) pharmacokinetic data (280 venous samples) from a phase I single (50 mg) dose study in healthy older people (n = 20, 65-79 years); (ii) pharmacokinetic, 18F-fallypride D2/3 receptor imaging and clinical outcome data on patients with Alzheimer's disease who were prescribed amisulpride (25-75 mg daily) to treat psychosis as part of an open study (n = 28; 69-92 years; 41 blood samples, five pretreatment scans, 19 post-treatment scans); and (iii) 18F-fallypride imaging of an antipsychotic free Alzheimer's disease control group (n = 10, 78-92 years), to provide additional pretreatment data. Non-linear mixed effects modelling was used to describe pharmacokinetic-occupancy curves in caudate, putamen and thalamus. Model outputs were used to estimate threshold steady state blood concentration and occupancy required to elicit a clinically relevant response (>25% reduction in scores on delusions, hallucinations and agitation domains of the Neuropsychiatric Inventory) and extrapyramidal side effects (Simpson Angus Scale scores > 3). Average steady state blood levels were low (71 ± 30 ng/ml), and associated with high D2/3 occupancies (65 ± 8%, caudate; 67 ± 11%, thalamus; 52 ± 11%, putamen). Antipsychotic clinical response occurred at a threshold concentration of 20 ng/ml and D2/3 occupancies of 43% (caudate), 25% (putamen), 43

  15. Reactions of O‑ with D2 at temperatures below 300 K (United States)

    Plašil, Radek; Tran, Thuy D.; Roučka, Štěpán; Rednyk, Serhiy; Kovalenko, Artem; Jusko, Pavol; Mulin, Dmytro; Zymak, Illia; Dohnal, Petr; Glosík, Juraj


    The reaction of O‑ anions with molecular deuterium D2 has been studied experimentally using a cryogenic 22-pole radiofrequency ion trap. Two reaction channels were observed. In the associative detachment D2O and an electron are formed and for atom transfer formation OD‑ + D was observed. The rate coefficients of the reactions have been determined at temperatures below 300 K. The reaction rate coefficient k 1 of the associative detachment increases with decreasing temperature from k 1(300 K) = 0.5 × 10‑9 cm3 s‑1 at 300 K up to k 1(70 K) = 1.2 × 10‑9 cm3 s‑1 at 70 K both with 30 % overall uncertainty.

  16. Neurovascular coupling to D2/D3 dopamine receptor occupancy using simultaneous PET/functional MRI

    DEFF Research Database (Denmark)

    Sander, Christin Y; Hooker, Jacob M; Catana, Ciprian


    This study employed simultaneous neuroimaging with positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) to demonstrate the relationship between changes in receptor occupancy measured by PET and changes in brain activity inferred by fMRI. By administering the D2/D3...... responses and receptor occupancies. The distinct CBV magnitudes between putamen and caudate at matched occupancies approximately matched literature differences in basal dopamine levels, suggesting that the relative fMRI measurements reflect basal D2/D3 dopamine receptor occupancy. These results can provide...... a basis for models that relate dopaminergic occupancies to hemodynamic changes in the basal ganglia. Overall, these data demonstrate the utility of simultaneous PET/fMRI for investigations of neurovascular coupling that correlate neurochemistry with hemodynamic changes in vivo for any receptor system...

  17. Pre- and Postsynaptic Role of Dopamine D2 Receptor DD2R in Drosophila Olfactory Associative Learning

    Directory of Open Access Journals (Sweden)

    Cheng Qi


    Full Text Available Dopaminergic neurons in Drosophila play critical roles in diverse brain functions such as motor control, arousal, learning, and memory. Using genetic and behavioral approaches, it has been firmly established that proper dopamine signaling is required for olfactory classical conditioning (e.g., aversive and appetitive learning. Dopamine mediates its functions through interaction with its receptors. There are two different types of dopamine receptors in Drosophila: D1-like (dDA1, DAMB and D2-like receptors (DD2R. Currently, no study has attempted to characterize the role of DD2R in Drosophila learning and memory. Using a DD2R-RNAi transgenic line, we have examined the role of DD2R, expressed in dopamine neurons (i.e., the presynaptic DD2R autoreceptor, in larval olfactory learning. The function of postsynaptic DD2R expressed in mushroom body (MB was also studied as MB is the center for Drosophila learning, with a function analogous to that of the mammalian hippocampus. Our results showed that suppression of presynaptic DD2R autoreceptors impairs both appetitive and aversive learning. Similarly, postsynaptic DD2R in MB neurons appears to be involved in both appetitive and aversive learning. The data confirm, for the first time, that DD2R plays an important role in Drosophila olfactory learning.

  18. The four-fermion interaction in D=2,3,4: a nonperturbative treatment


    Rochev, V. E.; Saponov, P. A.


    A new nonperturbative approach is used to investigate the Gross-Neveu model of four fermion interaction in the space-time dimensions 2, 3 and 4, the number $N$ of inner degrees of freedom being a fixed integer. The spontaneous symmetry breaking is shown to exist in $D=2,3$ and the running coupling constant is calculated. The four dimensional theory seems to be trivial.

  19. Membangun Embedded Linux Pada ALIX3d2 Dengan Buildroot Pada Aplikasi Stasiun Cuaca


    Febridiani, Lintang Dwi; Arif, Sahrul


    Embedded computer memerlukan sistem operasi yang cukup padat namun handal untuk menjalankan fungsi tertentu secara kontinyu. Embedded Linux menggunakan kernel Linux dengan sumber yang terbatas sebagai inti dari sistem operasi. Pada kegiatan ini, Buildroot dipilih untuk membangun sistem Embedded Linux karena memiliki kode sumber yang lengkap untuk komputer papan tunggal ALIX 3d2. Embedded linux yang dibangun untuk stasiun cuaca dengan menggunakan sensor/transducer dapat berjalan dengan baik pa...

  20. Cooperation in 5G HetNets: Advanced Spectrum Access and D2D Assisted Communications


    Tsiropoulos, Georgios I.; Yadav, Animesh; Zeng, Ming; Dobre, Octavia A.


    The evolution of conventional wireless communication networks to the fifth generation (5G) is driven by an explosive increase in the number of wireless mobile devices and services, as well as their demand for all-time and everywhere connectivity, high data rates, low latency, high energy-efficiency and improved quality of service. To address these challenges, 5G relies on key technologies, such as full duplex (FD), device-to-device (D2D) communications, and network densification. In this arti...

  1. LTE D2D communication for collaborative wearable sensor networks: A connectivity analysis


    STERI GARY; Baldini, Gianmarco; Goratti, Leonardo


    While the demand for wearable sensor devices is going to rise significantly in the near future, Long Term Evolution (LTE) chips are becoming progressively less expensive and rich in functionalities, suggesting for a strong integration between these two technologies. Moreover, the introduction of the Device-to-Device (D2D) feature in LTE envisages direct communication for basically any kind of device, and wearable sensors can be one of those. In this way, collaborative applications based on we...

  2. Power Control for D2D Underlay Cellular Networks With Channel Uncertainty

    KAUST Repository

    Memmi, Amen


    Device-to-device (D2D) communications underlying the cellular infrastructure are a technology that have been proposed recently as a promising solution to enhance cellular network capabilities. It improves spectrum utilization, overall throughput, and energy efficiency while enabling new peer-to-peer and location-based applications and services. However, interference is the major challenge, since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this paper, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Existing results on D2D underlay networks assume perfect channel state information (CSI). This assumption is usually unrealistic in practice due to the dynamic nature of wireless channels. Thus, it is of great interest to study and evaluate achievable performances under channel uncertainty. Differently from previous works, we are assuming that the CSI may be imperfect and include estimation errors. In the centralized approach, we derive the optimal powers that maximize the coverage probability and the rate of the cellular user while scheduling as many D2D links as possible. These powers are computed at the base station (BS) and then delivered to the users, and hence the name “centralized”. For the distributed method, the ON–OFF power control and the truncated channel inversion are proposed. Expressions of coverage probabilities are established in the function of D2D links intensity, pathloss exponent, and estimation error variance. Results show the important influence of CSI error on achievable performances and thus how crucial it is to consider it while designing networks and evaluating performances.

  3. Dissociative ionization of H2 and D2 by electron impact near threshold

    NARCIS (Netherlands)

    Boesten, L.G.J.; Heideman, H.G.M.

    We have studied the dissciative ionization of H2 and D2 by electron impact. It is found that in the vicinity of the 2Σ+g dissociation threshold of H+2 (18.08 eV) a significant fraction of the produced protons originates from the process e + H2 → H− + H+ + e (threshold at 17.34 eV). Similar results

  4. A structure-activity analysis of biased agonism at the dopamine D2 receptor. (United States)

    Shonberg, Jeremy; Herenbrink, Carmen Klein; López, Laura; Christopoulos, Arthur; Scammells, Peter J; Capuano, Ben; Lane, J Robert


    Biased agonism offers an opportunity for the medicinal chemist to discover pathway-selective ligands for GPCRs. A number of studies have suggested that biased agonism at the dopamine D2 receptor (D2R) may be advantageous for the treatment of neuropsychiatric disorders, including schizophrenia. As such, it is of great importance to gain insight into the SAR of biased agonism at this receptor. We have generated SAR based on a novel D2R partial agonist, tert-butyl (trans-4-(2-(3,4-dihydroisoquinolin-2(1H)-yl)ethyl)cyclohexyl)carbamate (4). This ligand shares structural similarity to cariprazine (2), a drug awaiting FDA approval for the treatment of schizophrenia, yet displays a distinct bias toward two different signaling end points. We synthesized a number of derivatives of 4 with subtle structural modifications, including incorporation of cariprazine fragments. By combining pharmacological profiling with analytical methodology to identify and to quantify bias, we have demonstrated that efficacy and biased agonism can be finely tuned by minor structural modifications to the head group containing the tertiary amine, a tail group that extends away from this moiety, and the orientation and length of a spacer region between these two moieties.

  5. Design Concepts of Emergency Response Robot Platform K-R2D2

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Sun Young; Jeong, Kyungmin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)


    From the analysis for various mobile robots competed in DARPA Robotics Challenge, there are some drawbacks in using two or four legs because bipedal locomotion is not yet suitable for maintaining stability and quadrupedal locomotion is difficult to go through narrow aisles. Motivated by the above observations, we propose a K-R2D2 robot platform with three legs arranged in the form of a triangle like as R2-D2 robot which is a fictional robot character in the Star Wars movies. This robot has 3 legs with tracks in each sole of the leg. It is statically stable since there are three contact points to ground. In addition, three legs are also possible to design a structure walking stairs that can expand and contract in the vertical direction. This paper has presented the conceptual design, it is developed on the purpose of quick response instead of emergent workers to the extreme conditions disasters. This robot is emergency response robot platform KR2D2 with three legs, which is statically stable to walk or wheel depending on the terrains and move quickly as possible as on uneven terrain or stairs.

  6. Search for cold fusion using Pd-D2O cells and Ti-D mixtures (United States)

    Hill, John C.; Stassis, C.; Shinar, J.; Goldman, A. I.; Folkerts, R.; Schwellenbach, D. D.; Peterson, D. T.; Widrig, C.; Porter, M.; Benesh, C. J.; Vary, J. P.


    We have searched for cold fusion produced in an electrolytic cell with Pd cathode and Pt anode. The electrolyte was 0.1 molar LiOD in 99.8% D2O. A 2-mm rod of polycrystalline Pd and a 4-mm rod of single crystal Pd were used. No radiation was detected above background by a BF3 neutron and Ge γ-X detector. The D2 loading of the Pd was 0.8 D per Pd atom reaching saturation after 4 hours. We also attempted to duplicate the work of Scaramuzzi and co-workers on the Ti-D2 system. Both powder and pieces of Ti were used. The material was cycled several times between 1100 K and 77 K. No neutron, γ- or x-ray emission above background was observed. The results of a barrier penetration calculation for H-like atoms are presented. The high fusion rates reported for PdD x . are much larger than those expected from theoretical calculations on these systems.

  7. Angular distributions of H-induced HD and D2 desorptions from the Si(100) surfaces (United States)

    Inanaga, S.; Kiyonaga, T.; Rahman, F.; Khanom, F.; Namiki, A.; Lee, J.


    We measured angular distributions of HD and D2 molecules desorbed via the reactions H +D/Si(100)→HD [abstraction (ABS)] and H +D/Si(100)→D2 [adsorption-induced-desorption (AID)], respectively. It was found that the angular distribution of HD molecules desorbed along ABS is broader than that of D2 molecules desorbed along AID, i.e., the former could be fit with cos2.0±0.2θ, while the latter with cos5.0±0.5θ. This difference of the angular distributions between the two reaction paths suggests that their dynamic mechanisms are different. The observed cos2θ distribution for the ABS reaction was reproduced by the classical trajectory calculations over the London-Eyring-Polanyi-Sato potential-energy surfaces. The simulation suggests that the HD desorption along the ABS path takes place along the direction of Si-D bonds, but the apparent angular distribution is comprised of multiple components reflecting the different orientations of D-occupied Si dimers in the (2×1) and (1×2) double domain structures.

  8. Device-Relaying in Cellular D2D Networks: A Fairness Perspective

    KAUST Repository

    Chaaban, Anas


    Device-to-Device (D2D) communication is envisioned to play a key role in 5G networks as a technique for meeting the demand for high data rates. In a cellular network, D2D allows not only direct communication between users, but also device relaying. In this paper, a simple instance of device-relaying is investigated, and its impact on fairness among users is studied. Namely, a cellular network consisting of two D2D-enabled users and a base-station (BS) is considered. Thus, the users who want to establish communication with the BS can act as relays for each other’s signals. While this problem is traditionally considered in the literature as a multiple-access channel with cooperation in the uplink, and a broadcast channel with cooperation in the downlink, we propose a different treatment of the problem as a multi-way channel. A simple communication scheme is proposed, and is shown to achieve significant gain in terms of fairness (measured by the symmetric rate supported) in comparison to the aforementioned traditional treatment.

  9. Probing the interface strain in a 3D-2D van der Waals heterostructure (United States)

    Sun, Xin; Shi, Jian; Washington, Morris A.; Lu, Toh-Ming


    The interaction at a van der Waals (vdW) epitaxial interface is perceived to be too weak to induce substantial elastic strain in films due to the weak nature of dipole-dipole interactions. Recent research on discovering giant strain in vdW heterostructures in 2D-2D configurations has reformed such an understanding. In this letter, the study on strain was extended to the regime of 3D-2D vdW heterostructures. Using temperature dependent Raman spectroscopy, the strain behaviors were revealed, through the change of phonon frequency, at a vdW epitaxial interface of CdS-mica. Although the interface was free of interactions for relatively thick CdS films, it was found that at least 0.4% strain can be borne at the interface when the film was only 6 nm thick and the strain was estimated to be 1.2% if a two-monolayer can be grown. The finding suggests that non-trivial strain could be enabled in 3D-2D vdW heterostructures if the thickness can be well-controlled, providing an avenue for strain engineering. This work also indicated a different changing tendency in the linewidth of phonon scattering as a function of temperature, which may be related to defects and serve as a reference for studying the linewidth of ultrathin films.

  10. Water dissociation and CO oxidation over Au/anatase catalyst. A DFT-D2 study (United States)

    Saqlain, Muhammad Adnan; Hussain, Akhtar; Siddiq, Muhammad; Leitão, Alexandre A.


    With the help of DFT-D2 methodology, we have investigated the adsorption of water on clean anatase(001) and Au/anatase(001). In the former case, adsorption energies of H2O differ to small extent computed employing GGA = PW91 and DFT-D2 methods. While the GGA = PW91 predicts that water would desorb close to 650 K on the TiO2 surface, the DFT-D2 predicts that desorption is most likely to occur above 700 K. A comparison of water adsorption on TiO2 and Au/TiO2 surfaces shows that the TiO2 prefers dimer adsorption whereas the Au/TiO2 prefers monomer adsorption. We found that the diffusion of surface hydroxyls on to the Au cluster from the Au/TiO2 periphery is unlikely and it seems that the CO oxidation would occur at the Au/TiO2 boundary. The results show that water dissociation and CO oxidation steps occur easily on Au/TiO2 indicating that this could be good alternative catalyst for water gas shift reaction industry.

  11. Spontaneous dissociation and rovibrational structure of the metastable D2- anion (United States)

    Mezdari, Ferid; de Ruette, Nathalie; Urbain, Xavier


    Long-lived rovibrational states of the metastable D2 - molecular anion, with lifetimes of the order of microseconds, were studied by recording the time-of-flight difference between D and D- fragments produced by spontaneous dissociation of the D2 - complex. The simulated time-of-flight spectrum was adjusted to the experimental results, allowing us to extract the resonance energy relative to the dissociation threshold. A single value was found, 22.8 ±0.3 meV, which is somewhat larger than resonance energies predicted by theory for long-lived D2 - rovibrational states with (J ,v ) quantum numbers (37,0), (37,1), and (38,0) [Phys. Rev. A 75, 012507 (2007), 10.1103/PhysRevA.75.012507]. This discrepancy seems due to the extreme sensitivity of these metastable states to minute features of the potential energy curve. The spectral feature is explained by the competition between autodetachment and spontaneous dissociation decay channels.

  12. VORFFIP-driven dock: V-D2OCK, a fast and accurate protein docking strategy. (United States)

    Segura, Joan; Marín-López, Manuel Alejandro; Jones, Pamela F; Oliva, Baldo; Fernandez-Fuentes, Narcis


    The experimental determination of the structure of protein complexes cannot keep pace with the generation of interactomic data, hence resulting in an ever-expanding gap. As the structural details of protein complexes are central to a full understanding of the function and dynamics of the cell machinery, alternative strategies are needed to circumvent the bottleneck in structure determination. Computational protein docking is a valid and valuable approach to model the structure of protein complexes. In this work, we describe a novel computational strategy to predict the structure of protein complexes based on data-driven docking: VORFFIP-driven dock (V-D2OCK). This new approach makes use of our newly described method to predict functional sites in protein structures, VORFFIP, to define the region to be sampled during docking and structural clustering to reduce the number of models to be examined by users. V-D2OCK has been benchmarked using a validated and diverse set of protein complexes and compared to a state-of-art docking method. The speed and accuracy compared to contemporary tools justifies the potential use of VD2OCK for high-throughput, genome-wide, protein docking. Finally, we have developed a web interface that allows users to browser and visualize V-D2OCK predictions from the convenience of their web-browsers.

  13. Annihilation rates of 3D2(2--) and 3D3(3--) heavy quarkonia (United States)

    Wang, Tianhong; Fu, Hui-Feng; Jiang, Yue; Li, Qiang; Wang, Guo-Li


    We calculate the annihilation decay rates of the 3D 2(2--) and 3D 3(3--) charmonia and bottomonia by using the instantaneous Bethe-Salpeter (BS) method. The wave functions of states with quantum numbers JPC = 2-- and 3-- are constructed. By solving the corresponding instantaneous BS equations, we obtain the mass spectra and wave functions of the quarkonia. The annihilation amplitude is written within Mandelstam formalism and the relativistic corrections are taken into account properly. This is important, especially for high excited states, since their relativistic corrections are large. The results for the 3g channel are as follows: Γ13D2(cc¯)→ggg = 9.24 keV, Γ13D3(cc¯)→ggg = 25.0 keV, Γ13D2(bb¯)→ggg = 1.87 keV and Γ13D3(bb¯)→ggg = 0.815 keV.

  14. Involvement of GluD2 in Fear-Conditioned Bradycardia in Mice.

    Directory of Open Access Journals (Sweden)

    Hiroko Kotajima-Murakami

    Full Text Available Lesions in the cerebellar vermis abolish acquisition of fear-conditioned bradycardia in animals and human patients. The δ2 glutamate receptor (GluD2 is predominantly expressed in cerebellar Purkinje cells. The mouse mutant ho15J carries a spontaneous mutation in GluD2 and these mice show a primary deficiency in parallel fiber-Purkinje cell synapses, multiple innervations of Purkinje cells by climbing fibers, and impairment of long-term depression. In the present study, we used ho15J mice to investigate the role of the cerebellum in fear-conditioned bradycardia. We recorded changes in heart rate of ho15J mice induced by repeated pairing of an acoustic (conditioned stimulus (CS with an aversive (unconditioned stimulus (US. The mice acquired conditioned bradycardia on Day 1 of the CS-US phase, similarly to wild-type mice. However, the magnitude of the conditioned bradycardia was not stable in the mutant mice, but rather was exaggerated on Days 2-5 of the CS-US phase. We examined the effects of reversibly inactivating the cerebellum by injection of an antagonist against the α-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor (AMPAR. The antagonist abolished expression of conditioned responses in both wild-type and ho15J mice. We conclude that the GluD2 mutation in the ho15J mice affects stable retention of the acquired conditioned bradycardia.

  15. Design Study of the High Luminosity LHC Recombination Dipole (D2)

    Energy Technology Data Exchange (ETDEWEB)

    Sabbi, GianLuca; Wang, Xiaorong


    The interaction region design of the high-luminosity LHC requires replacing the recombination dipole magnets (D2) with new ones. The preliminary specifications include an aperture of 105 mm, with 186 mm separation between the twin-aperture axes, and an operating field in the range of 3.5 to 4.5 T. The main design challenge is to decouple the magnetic field in the two apertures and ensure good field quality. The approach adopted for the present D2 magnets, using the iron yoke as a shield between the two apertures, leads to large saturation effects. In this study, we propose an alternative approach where the iron yoke is designed primarily for low saturation, and the resulting large but current-independent cross-talk between the apertures is corrected with an asymmetric arrangement of the conductor blocks. A preliminary solution based on the LHC dipole cable is presented, and the expected harmonics for geometric, saturation and persistent current effects are provided. Finally, the feasibility of an operating field at the high end of the range considered is discussed, to minimize the D2 magnet length and facilitate the space allocation for other components.

  16. Quantification of myocardial perfusion using cardiac magnetic resonance imaging correlates significantly to rubidium-82 positron emission tomography in patients with severe coronary artery disease: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Qayyum, Abbas A., E-mail: [Department of Cardiology and Cardiac Catheterization Laboratory 2014, The Heart Centre, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Hasbak, Philip, E-mail: [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Larsson, Henrik B.W., E-mail: [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Functional Imaging Unit, Diagnostic Department, Glostrup Hospital, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Ndr. Ringvej 57, 2600 Copenhagen (Denmark); Christensen, Thomas E., E-mail: [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Ghotbi, Adam A., E-mail: [Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); Mathiasen, Anders B., E-mail: [Department of Cardiology and Cardiac Catheterization Laboratory 2014, The Heart Centre, Rigshospitalet, University Hospital of Copenhagen and Faculty of Health Sciences, Copenhagen University, Blegdamsvej 9, 2100 Copenhagen (Denmark); and others


    Introduction: Aim was to compare absolute myocardial perfusion using cardiac magnetic resonance imaging (CMRI) based on Tikhonov's procedure of deconvolution and rubidium-82 positron emission tomography (Rb-82 PET). Materials and methods: Fourteen patients with coronary artery stenosis underwent rest and adenosine stress imaging by 1.5-Tesla MR Scanner and a mCT/PET 64-slice Scanner. CMRI were analyzed based on Tikhonov's procedure of deconvolution without specifying an explicit compartment model using our own software. PET images were analyzed using standard clinical software. CMRI and PET data was compared with Spearman's rho and Bland–Altman analysis. Results: CMRI results were strongly and significantly correlated with PET results for the absolute global myocardial perfusion differences (r = 0.805, p = 0.001) and for global myocardial perfusion reserve (MPR) (r = 0.886, p < 0.001). At vessel territorial level, CMRI results were also significantly correlated with absolute PET myocardial perfusion differences (r = 0.737, p < 0.001) and MPR (r = 0.818, p < 0.001). Each vessel territory had similar strong correlation for absolute myocardial perfusion differences (right coronary artery (RCA): r = 0.787, p = 0.001; left anterior descending artery (LAD): r = 0.796, p = 0.001; left circumflex artery (LCX): r = 0.880, p < 0.001) and for MPR (RCA: r = 0.895, p < 0.001; LAD: r = 0.886, p < 0.001; LCX: r = 0.886, p < 0.001). Conclusion: On a global and vessel territorial basis, CMRI-measured absolute myocardial perfusion differences and MPR were strongly and significantly correlated with the Rb-82 PET findings.

  17. Dynamic electrophysical characterization of rubidium polytungstate, Rb{sub 4}W{sub 11}O{sub 35}, under fast humidity impact

    Energy Technology Data Exchange (ETDEWEB)

    Bravina, S.L. [Institute of Physics of National Academy of Sciences of Ukraine, 46, Nauki Ave., Kiev 03028 (Ukraine); Morozovsky, N.V., E-mail: [Institute of Physics of National Academy of Sciences of Ukraine, 46, Nauki Ave., Kiev 03028 (Ukraine); Solodovnikov, S.F. [Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 3, Acad. Lavrent' ev Ave., Novosibirsk 630090 (Russian Federation); Novosibirsk National Research State University, Pirogov St. 2, Novosibirsk 630090 (Russian Federation); Basovich, O.M. [Baikal Institute of Nature Management, Siberian Branch, Russian Academy of Sciences, 8, Sakh' yanova Str., Ulan-Ude 670047 (Russian Federation); Khaikina, E.G. [Baikal Institute of Nature Management, Siberian Branch, Russian Academy of Sciences, 8, Sakh' yanova Str., Ulan-Ude 670047 (Russian Federation); Buryat State University, 24 a, Smolin St., Ulan-Ude 670000 (Russian Federation)


    The electrophysical reaction of rubidium polytungstate Rb{sub 4}W{sub 11}O{sub 35} (RWO) on fast humidity impact has been investigated by studying the influence of wet air pulse of 1–3 s of duration on the peculiarities of dynamic current–voltage (I–V-) and charge-voltage (Q–V-) loops and transient current–time (I–t-) curves. The revealed peculiarities of hysteretic I–V- and Q–V-loops and I–t-curves for RWO subjected to humidity impact were compared with similar ones observed for water damaged hydrogen-bounded ferroelectric triglycine sulphate (TGS) crystals. The obtained data indicate at least two possible scenarios of polar reaction on the humidity impact, namely protonic/ionic space charge transfer and ferroelectric-like reversible polarization in surface RWO conglomerate disturbed by dipolar H{sub 2}O adsorbate. Owing to a high surface activity the RWO can be considered as one of promising materials for creating humidity sensitive elements of environment monitoring systems. The direct humidity-to-frequency conversion was realized using LC resonance or RC-relaxation generating units. - Highlights: • Electrophysical reaction of Rb{sub 4}W{sub 11}O{sub 35} on fast humidity impact was studied. • Dynamic current- and charge-voltage loops and transient currents were examined. • Appearance of displacement current maxima under wet air pulse was revealed. • Ionic transfer and ferroelectric-like polarization are likely reasons of the maxima.

  18. Testing of conductivity/calcium and rubidium/strontium ratios as indicators of the chemical stability of a river: comparison with a biological indicator. (United States)

    Nirel, P M V; Lazzarotto, J


    It is customary to detect pollution in a water flow by monitoring the increase of sensitive elements concentrations (NH4+, PO4(3-), NO3-...). However, concentrations are dependent on the flow rate and these compounds are not conservative, implying a concentration decrease downstream leading to false negative diagnosis of pollution impact. The use of elemental ratios of conservative compounds should diminish these pitfalls. We then thought of the chi/Ca (conductivity/calcium) and Rb/Sr (rubidium/strontium) ratios as water chemical stability indicators to clearly identify and discriminate point from diffuse pollutions. This hypothesis has been tested on 12 brooks located in the basin of Lake Geneva, during 2 hydrological years. The results were compared to the observed land use of the watershed and a biological indicator: the Pollution Sensitivity Index (PSI). The PSI is calculated from diatom taxonomy and evaluates biological quality with a grade ranging from 0 to 20 (bad to excellent). The main results of the research can be summarized as follows. The pollution signal is observable far downstream of the pollution site. Both chi/Ca and Rb/Sr ratios are water quality indicators expressing the stability of water chemistry. They can both be used to detect diffuse and point pollution impact. These indicators provide complementary information: chi/Ca variations increase in case of point pollution; Rb/Sr variations increase when diffuse pollutions occur. The results obtained with the indicators chi/Ca and Rb/Sr agree with biological indicator and observation of the land use. chi/Ca and Rb/Sr ratios represent important tools to identify and discriminate point source pollution from diffuse pollution.

  19. Effect of Rubidium-Incorporation on the Structural, Electrical, and Photovoltaic Properties of Methylammonium Lead Iodide-based Perovskite Solar Cells. (United States)

    Park, Ik Jae; Seo, Seongrok; Park, Min Ah; Lee, Sangwook; Kim, Dong Hoe; Zhu, Kai; Shin, Hyunjung; Kim, Jin Young


    We report the electrical properties of rubidium-incorporated methylammonium lead iodide ((RbxMA1-x)PbI3) films and the photovoltaic performance of (RbxMA1-x)PbI3 film-based p-i-n-type perovskite solar cells (PSCs). The incorporation of a small amount of Rb(+) (x=0.05) increases both the open circuit voltage (Voc) and the short circuit photocurrent density (Jsc) of the PSCs, leading to an improved power conversion efficiency (PCE). However, a high fraction of Rb(+) incorporation (x=0.1 and 0.2) decreases the Jsc and thus the PCE, which is attributed to the phase segregation of the single tetragonal perovskite phase to a MA-rich tetragonal perovskite phase and a RbPbI3 orthorhombic phase at high Rb fractions. Conductive atomic force microscopic and admittance spectroscopic analyses reveal that the single-phase (Rb0.05MA0.95)PbI3 film has a high electrical conductivity due to a reduced deep-level trap density. We also found that Rb substitution enhances the diode characteristics of the PSC, as evidenced by the reduced reverse saturation current (J0). The optimized (RbxMA1-x)PbI3 PSCs exhibited a PCE of 18.8% with negligible hysteresis in the photocurrent-voltage curve. The results from this work enhance the understanding of the effect of Rb incorporation into organic-inorganic hybrid halide perovskites and enables the exploration of Rb-incorporated mixed perovskites for various applications, such as solar cells, photodetectors, and light-emitting diodes.

  20. Beta-decay energies and masses of short-lived isotopes of rubidium, caesium, francium, and radium

    CERN Document Server

    Westgaard, L; Nyman, G H; Roeckl, E


    Total decay energies have been measured for a number of neutron- deficient Rb and Cs isotopes, as well as for some neutron-rich isotopes of Fr and Ra. Mass separated sources were produced at the ISOLDE on-line separator at CERN. By applying two different beta - gamma coincidence methods, Q values or their lower limits were determined for /sup 76-78/Rb, /sup 80/Rb, /sup 121-124/Cs, /sup 222 /Fr, /sup 224-226/Fr, /sup 229/Ra and /sup 229/Ac. For many of these nuclei, the atomic mass excesses could be derived, allowing the comparison of masses of far unstable nuclei with predictions from mass formulae. The odd-odd nuclei /sup 76/Rb and /sup 78/Rb appear to be 1-1/sup 1///sub 2/ MeV more strongly bound than expected from the systematics. (70 refs).

  1. Radio resource management scheme and outage analysis for network-assisted multi-hop D2D communications

    Directory of Open Access Journals (Sweden)

    Leila Melki


    Full Text Available In a cellular network it's very difficult to make spectrum resource more efficiently. Device-to-Device (D2D technology enables new service opportunities, and provides high throughput and reliable communication while reducing the base station load. For better total performance, short-range D2D links and cellular links share the same radio resource and the management of interference becomes a crucial task. Here we argue that single-hop D2D technology can be used to further improve cellular networks performance if the key D2D radio resource management algorithms are suitably extended to support multi-hop D2D communications. Aiming to establish a new paradigm for the analysis and design of multi-hop D2D communications, We propose a radio resource allocation for multi-hop D2D routes based on interference avoidance approach in LTE-A networks. On top of that, we investigate the outage probability of D2D communication. We first introduce a new definition of outage probability by considering the maximum distance to be allowable for single-hop transmission. Then we study and analyze the outage performance of a multi-hop D2D route. We derive the general closed form expression of outage probability of the multi-hop D2D routes. The results demonstrate that the D2D radio, sharing the same resources as the cellular network, provide higher capacity compared to pure cellular communication where all the data is transmitted through the base station. They also demonstrate that the new method of calculation of D2D multi hop outage probability has better performance than classical method defined in the literature.

  2. Biological Insights of the Dopaminergic Stabilizer ACR16 at the Binding Pocket of Dopamine D2 Receptor. (United States)

    Ekhteiari Salmas, Ramin; Seeman, Philip; Aksoydan, Busecan; Stein, Matthias; Yurtsever, Mine; Durdagi, Serdar


    The dopamine D2 receptor (D2R) plays an important part in the human central nervous system and it is considered to be a focal target of antipsychotic agents. It is structurally modeled in active and inactive states, in which homodimerization reaction of the D2R monomers is also applied. The ASP2314 (also known as ACR16) ligand, a D2R stabilizer, is used in tests to evaluate how dimerization and conformational changes may alter the ligand binding space and to provide information on alterations in inhibitory mechanisms upon activation. The administration of the D2R agonist ligand ACR16 [ 3 H](+)-4-propyl-3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4]oxazin-9-ol ((+)PHNO) revealed K i values of 32 nM for the D2 high R and 52 μM for the D2 low R. The calculated binding affinities of ACR16 with post processing molecular dynamics (MD) simulations analyses using MM/PBSA for the monomeric and homodimeric forms of the D2 high R were -9.46 and -8.39 kcal/mol, respectively. The data suggests that the dimerization of the D2R leads negative cooperativity for ACR16 binding. The dimerization reaction of the D2 high R is energetically favorable by -22.95 kcal/mol. The dimerization reaction structurally and thermodynamically stabilizes the D2 high R conformation, which may be due to the intermolecular forces formed between the TM4 of each monomer, and the result strongly demonstrates dimerization essential for activation of the D2R.

  3. Raman spectrum of the solid electrolytes LiI·H2O and LiI·D2O

    DEFF Research Database (Denmark)

    Poulsen, Finn Willy


    The Raman spectra of cubic LiI·H2O and LiI·D2O have been revised. The spectra reveal only internal and librational modes of H2O (D2O). The isotopic ratios νH/νD, are in the range 1.33-1.78......The Raman spectra of cubic LiI·H2O and LiI·D2O have been revised. The spectra reveal only internal and librational modes of H2O (D2O). The isotopic ratios νH/νD, are in the range 1.33-1.78...

  4. Impaired Timing Precision Produced by Striatal D2 Receptor Overexpression is Mediated by Cognitive and Motivational Deficits (United States)

    Ward, Ryan D.; Kellendonk, Christoph; Simpson, Eleanor H.; Lipatova, Olga; Drew, Michael R.; Fairhurst, Stephen; Kandel, Eric R.; Balsam, Peter D


    Increased striatal dopamine D2 receptor activity is thought to contribute to the pathophysiology of schizophrenia. To model this condition in mice, Kellendonk et al. (2006) generated transgenic mice which selectively overexpress the D2 receptor in striatum (D2OE). Drew et al. (2007) reported that D2OE mice display deficits in interval timing and motivation. The present study further explored the impaired timing in D2OE mice. Experiment 1 assessed the role of motivation in producing timing deficits in the peak procedure and found that performance in D2OE mice was improved by increasing motivation. In addition, performance was impaired in control mice when motivation was decreased. In Experiment 2, we found that D2OE mice have no timing impairment when tested using the bisection task, a procedure in which the measure of timing performance is less influenced by motivation to respond. In Experiment 3, we also used the bisection task and found selective impairment in timing of long durations in D2OE mice. These results suggest that striatal D2 overexpression impairs timing by decreasing motivation and through its impact on working memory and/or sustained attention. PMID:19634929

  5. Vitamin D2 Stability During the Refrigerated Storage of Ultraviolet B-Treated Cultivated Culinary-Medicinal Mushrooms. (United States)

    Slawinska, Aneta; Fornal, Emilia; Radzki, Wojciech; Jablonska-Rys, Ewa; Parfieniuk, Ewa


    The effects of ultraviolet B (UVB) irradiation on the synthesis of vitamin D2 and its stability during refrigerated storage was determined in fresh cultivated culinary-medicinal mushrooms (Agaricus bisporus, Pleurotus ostreatus, and Lentinus edodes) after harvest. The irradiated mushrooms were stored at 4°C for up to 10 days. The concentrations of vitamin D2 and ergosterol were determined using ultrahigh-performance liquid chromatography/tandem mass spectrometry. The cultivated mushrooms not treated with UVB were devoid of vitamin D2. After UVB irradiation, we obtained mushrooms with a large amount of ergocalciferol. A. bisporus showed the lowest vitamin D2 content (3.55 ± 0.11 μg D2/g dry weight); P. ostreatus contained 58.96 ± 1.15 μg D2/g dry weight, and L. edodes contained 29.46 ± 2.21 μg/g dry weight. During storage at 4°C, the amount of vitamin D2 was gradually decreased in P. ostreatus and L. edodes, whereas in A. bisporus vitamin D2 gradually increased until the sixth day, then decreased. Mushrooms exposed to UVB radiation contain a significant amount of vitamin D2 and are therefore an excellent food source of vitamin D.

  6. Glucose Regulates Cyclin D2 Expression in Quiescent and Replicating Pancreatic β-Cells Through Glycolysis and Calcium Channels (United States)

    Salpeter, Seth J.; Klochendler, Agnes; Weinberg-Corem, Noa; Porat, Shay; Granot, Zvi; Shapiro, A. M. James; Magnuson, Mark A.; Eden, Amir; Grimsby, Joseph; Glaser, Benjamin


    Understanding the molecular triggers of pancreatic β-cell proliferation may facilitate the development of regenerative therapies for diabetes. Genetic studies have demonstrated an important role for cyclin D2 in β-cell proliferation and mass homeostasis, but its specific function in β-cell division and mechanism of regulation remain unclear. Here, we report that cyclin D2 is present at high levels in the nucleus of quiescent β-cells in vivo. The major regulator of cyclin D2 expression is glucose, acting via glycolysis and calcium channels in the β-cell to control cyclin D2 mRNA levels. Furthermore, cyclin D2 mRNA is down-regulated during S-G2-M phases of each β-cell division, via a mechanism that is also affected by glucose metabolism. Thus, glucose metabolism maintains high levels of nuclear cyclin D2 in quiescent β-cells and modulates the down-regulation of cyclin D2 in replicating β-cells. These data challenge the standard model for regulation of cyclin D2 during the cell division cycle and suggest cyclin D2 as a molecular link between glucose levels and β-cell replication. PMID:21521747

  7. Dopamine-D2-receptor scintigraphy with {sup 123}I-Iodobenzofuran in malignant melanoma; Dopamin-D2-Rezeptorszintigraphie mit {sup 123}I-Jodbenzofuran beim malignen Melanom

    Energy Technology Data Exchange (ETDEWEB)

    Steinert, H. [Dept. fuer Medizinische Radiologie, Klinik fuer Nuklearmedizin, Universitaetsspital Zurich (Switzerland); Huch-Boeni, R.A. [Inst. fuer Diagnostische Radiologie, Universitaetsspital Zurich (Switzerland); Boeni, R. [Dermatologische Klinik, Universitaetsspital Zurich (Switzerland); Westera, G. [Dept. fuer Medizinische Radiologie, Klinik fuer Nuklearmedizin, Universitaetsspital Zurich (Switzerland); Buck, A. [Dept. fuer Medizinische Radiologie, Klinik fuer Nuklearmedizin, Universitaetsspital Zurich (Switzerland)


    In a prospective study the value of {sup 123}I-iodobenzofuran (IBF), a highly specific and affine dopamine-D2 receptor ligand was evaluated for the detection of melanoma metastases. With IBF-D2 receptor scintigraphy only 2 of 17 melanoma metastases could be detected. The interpretation of the abdomen was impaired by the hepatobiliary and renal excretion of the radionuclide. The ratio striatum/frontal cortex of 2,75 {+-} 0,49 3 h p.i. demonstrated a high D2-receptor binding of the ligand. IBF-D2-receptor scintigraphy is not suitable as a method of staging melanoma. (orig.) [Deutsch] In einer prospektiven Studie wurde die Wertigkeit von {sup 123}I-Jodbenzofuran (IBF), einem hochspezifischen und hochaffinen Dopamin-D2-Rezeptorliganden zum Nachweis von Melanommetastasen untersucht. Mit der IBF-D2-Rezeptorszintigraphie liessen sich nur 2 von 17 Melanommetastasen nachweisen. Die Beurteilung des Abdomens war durch die hepatobiliaere Ausscheidung des Radionuklids stark eingeschraenkt. Der Quotient Striatum/Frontalhirn von 2,75 {+-} 0,49 3 h p.i. belegte die hohe D2-Rezeptorbindung des Liganden. Die IBF-D2-Rezeptorszintigraphie ist als Staginguntersuchung beim Melanom nicht geeignet. (orig.)

  8. A2A-D2 receptor-receptor interaction modulates gliotransmitter release from striatal astrocyte processes. (United States)

    Cervetto, Chiara; Venturini, Arianna; Passalacqua, Mario; Guidolin, Diego; Genedani, Susanna; Fuxe, Kjell; Borroto-Esquela, Dasiel O; Cortelli, Pietro; Woods, Amina; Maura, Guido; Marcoli, Manuela; Agnati, Luigi F


    Evidence for striatal A2A-D2 heterodimers has led to a new perspective on molecular mechanisms involved in schizophrenia and Parkinson's disease. Despite the increasing recognition of astrocytes' participation in neuropsychiatric disease vulnerability, involvement of striatal astrocytes in A2A and D2 receptor signal transmission has never been explored. Here, we investigated the presence of D2 and A2A receptors in isolated astrocyte processes prepared from adult rat striatum by confocal imaging; the effects of receptor activation were measured on the 4-aminopyridine-evoked release of glutamate from the processes. Confocal analysis showed that A2A and D2 receptors were co-expressed on the same astrocyte processes. Evidence for A2A-D2 receptor-receptor interactions was obtained by measuring the release of the gliotransmitter glutamate: D2 receptors inhibited the glutamate release, while activation of A2A receptors, per se ineffective, abolished the effect of D2 receptor activation. The synthetic D2 peptide VLRRRRKRVN corresponding to the receptor region involved in electrostatic interaction underlying A2A-D2 heteromerization abolished the ability of the A2A receptor to antagonize the D2 receptor-mediated effect. Together, the findings are consistent with heteromerization of native striatal astrocytic A2A-D2 receptors that via allosteric receptor-receptor interactions could play a role in the control of striatal glutamatergic transmission. These new findings suggest possible new pathogenic mechanisms and/or therapeutic approaches to neuropsychiatric disorders. © 2016 International Society for Neurochemistry.

  9. Autoradiographic localization of dopamine D2-like receptors in the rabbit pulmonary vascular tree. (United States)

    Kobayashi, Y; Ricci, A; Rossodivita, I; Amenta, F


    In the present study, the pharmacological characteristics and the anatomical localization of dopamine D2-like receptor sites in the extraparenchymal and in the intraparenchymal portion of the rabbit pulmonary artery were investigated using combined radioligand binding and light microscope autoradiography with [3H]-spiroperidol (spiperone) as a ligand. The ligand was bound to sections of the pulmonary artery in a manner consistent with the labelling of dopamine D2-like receptors with an equilibrium dissociation constant (Kd) of about 2.4 +/- 0.07 nmol/l and a maximum density of binding sites of 65 +/- 4.5 fmol/mg tissue. In contrast, binding experiments made with sections of rabbit lung did not allow the evaluation of specific binding. Light microscope autoradiography showed the development of specific silver grains within the tunica adventitia of extraparenchymal branches of rabbit pulmonary artery and of large and, to a lesser extent, of medium-sized intraparenchymal branches of the pulmonary artery. No silver grains were found within small branches of the pulmonary artery or of the pulmonary vein. Development of adventitial silver grains was inhibited by compounds active at dopamine receptors. The greater sensitivity to displacement by domperidone, haloperidol, (-)-sulpiride and bromocriptine than to displacement by N-propyl-norapomorphine, quinpirole or clozapine suggests that the [3H]-spiroperidol binding sites observed in extraparenchymal, large and medium-sized branches of the pulmonary artery belong, probably, to the dopamine D2 receptor subtype. The possible pre-junctional localization of these sites is discussed.

  10. Ciliary neurotrophic factor mediates dopamine D2 receptor-induced CNS neurogenesis in adult mice. (United States)

    Yang, Peng; Arnold, Sheila A; Habas, Agata; Hetman, Michal; Hagg, Theo


    Neurogenesis continues in the adult forebrain subventricular zone (SVZ) and the dentate gyrus of the hippocampal formation. Degeneration of dopaminergic projections in Parkinson's disease and animals reduces, whereas ciliary neurotrophic factor (CNTF) promotes, neurogenesis. We tested whether the dopaminergic system promotes neurogenesis through CNTF. Astrocytes of the SVZ and dentate gyrus expressed CNTF and were close to dopaminergic terminals. Dopaminergic denervation in adult mice reduced CNTF mRNA by approximately 60%, whereas systemic treatment with the D2 agonist quinpirole increased CNTF mRNA in the SVZ and hippocampal formation, and in cultured astrocytes by 1.5-5 fold. The effect of quinpirole in vitro was blocked by the D2 antagonist eticlopride and did not cause astroglial proliferation or hypertrophy. Systemic quinpirole injections increased proliferation in wild-type mice by approximately 25-75% but not in CNTF-/- littermates or in the SVZ of mice infused with CNTF antibodies. Quinpirole increased the number of neuroblasts in wild-type but not in CNTF-/- littermates. Neurogenesis was reduced by approximately 20% in CNTF-/- mice, confirming the endogenous role of CNTF. Nigrostriatal denervation did not affect SVZ proliferation in CNTF-/- mice, suggesting that the dopaminergic innervation normally regulates neurogenesis through CNTF. Quinpirole acted on postsynaptic receptors as it reversed the reduced proliferation seen after dopaminergic denervation in wild-type mice. Thus, CNTF mediates dopaminergic innervation- and D2 receptor-induced neurogenesis in the adult forebrain. Because CNTF is predominantly expressed in the nervous system, this mechanism and the ability to pharmacologically modulate it have implications for Parkinson's disease and cell-replacement therapies for other disorders.

  11. Electroacupuncture-Induced Neuroprotection against Cerebral Ischemia in Rats: Role of the Dopamine D2 Receptor

    Directory of Open Access Journals (Sweden)

    Ming-Shu Xu


    Full Text Available Background. Cerebral ischemia is known to produce brain damage and related behavioural deficits, including memory deficits and motor disorders. Evidence shows that EA significantly promotes recovery of neurological function and thus improves quality of life. Objective. Evidence exists for the involvement of catecholamines in human neuroplasticity. A better understanding of dopaminergic (DAergic modulation in this process will be important. Methods. A total of 72 adult male Sprague-Dawley (SD rats were divided into 6 groups: normal, model, EA, spiperone group, EA + spiperone group, and pergolide. The middle cerebral artery occlusion (MCAO model was used in all 6 groups except the normal group. A behavioural assessment was conducted at 1, 3, 5, and 7 days after MCAO. The percent of brain infarct area was also determined 7 days after MCAO. Tyrosine hydroxylase (TH and growth-associated protein 43 (GAP-43 fluorescence double labeling was performed in the striatum. Results. In this study, we found that EA at Fengchi (GB20 acupoints resulted in marked improvements based on a behavioural assessment. Both TTC staining and GAP-43 immunofluorescence labeling results showed that EA treatment reduced ischemia injury and promoted neuroplasticity compared with the model group. The D2R-selective agonist, pergolide, showed similar results, but these results were reversed by the D2R-selective antagonist, spiperone. We also found that there were more colocalization and expression of GAP-43 and TH in the EA and pergolide groups than those in the other groups. Conclusion. These results suggest that the neuroplasticity induced by EA was mediated by D2 autoreceptors in DAergic neurons.

  12. Occupancy of pramipexole (Sifrol at cerebral dopamine D2/3 receptors in Parkinson's disease patients

    Directory of Open Access Journals (Sweden)

    Angela Deutschländer


    Full Text Available Whereas positron emission tomography (PET with the antagonist ligand [18F]fallypride reveals the composite of dopamine D2 and D3 receptors in brain, treatment of Parkinson's disease (PD patients with the D3-prefering agonist pramipexole should result in preferential occupancy in the nucleus accumbens, where the D3-subtype is most abundant. To test this prediction we obtained pairs of [18F]fallypride PET recordings in a group of nine PD patients, first in a condition of treatment as usual with pramipexole (ON-Sifrol; 3 × 0.7 mg p.d., and again at a later date, after withholding pramipexole 48–72 h (OFF-Sifrol; in that condition the serum pramipexole concentration had declined by 90% and prolactin levels had increased four-fold, in conjunction with a small but significant worsening of PD motor symptoms. Exploratory comparison with historical control material showed 14% higher dopamine D2/3 availability in the more-affected putamen of patients OFF medication. On-Sifrol there was significant (p ˂ 0.01 occupancy at [18F]fallypride binding sites in globus pallidus (8% thalamus (9% and substantia nigra (19%, as well as marginally significant occupancy in frontal and temporal cortex of patients. Contrary to expectation, comparison of ON- and OFF-Sifrol results did not reveal any discernible occupancy in nucleus accumbens, or elsewhere in the extended striatum; present methods should be sensitive to a 10% change in dopamine D2/3 receptor availability in striatum; the significant findings elsewhere in the basal ganglia and in cerebral cortex are consistent with a predominance of D3 receptors in those structures, especially in substantia nigra, and imply that therapeutic effects of pramipexole may be obtained at sites outside the extended striatum.

  13. Motor sequence learning in primate: role of the D2 receptor in movement chunking during consolidation. (United States)

    Tremblay, Pierre-Luc; Bedard, Marc-Andre; Levesque, Maxime; Chebli, Mark; Parent, Maxime; Courtemanche, Richard; Blanchet, Pierre J


    Motor learning disturbances have been shown in diseases involving dopamine insufficiency such as Parkinson's disease and schizophrenic patients under antipsychotic drug treatment. In non-human primates, motor learning deficits have also been observed following systemic administration of raclopride, a selective D2-receptor antagonist. These deficits were characterized by persistent fluctuations of performance from trial to trial, and were described as difficulties in consolidating movements following a learning period. Moreover, it has been suggested that these raclopride-induced fluctuations can result from impediments in grouping separate movements into one fluent sequence. In the present study, we explore the hypothesis that such fluctuations during movement consolidation can be prevented through the use of sumanirole - a highly selective D2 agonist - if administered before raclopride. Two monkeys were trained to execute a well known sequence of movements, which was later recalled under three pharmacological conditions: (1) no drug, (2) raclopride, and (3) sumanirole+raclopride. The same three pharmacological conditions were repeated with the two monkeys, trained this time to learn new sequences of movements. Results show that raclopride has no deleterious effect on the well known sequence, nor the sumanirole+raclopride co-administration. However, results on the new sequence to be learned revealed continuous fluctuations of performances in the raclopride condition, but not in the sumanirole+raclopride condition. These fluctuations occurred concurrently with a difficulty in merging separate movement components, known as a "chunking deficit". D2 receptors seem therefore to be involved in the consolidation of new motor skills, and this might involve the chunking of separate movements into integrated motor sequences.

  14. Dopamine D2 receptor status assessed by IBZM SPECT - A sensitive indicator for cerebral hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Tatsch, K.; Schwarz, J.; Welz, A. [Univ. of Munich (Germany)] [and others


    The striatum is highly sensitive to tissue hypoxia. Thus, it may be suggested that cerebral hypoxia could affect the integrity of the striatal receptor system. Purpose of the current SPECT investigations with IBZM was to evaluate whether hypoxic conditions cause detectable changes in the D2 receptor status. 25 controls and 30 pts with history of cerebral hypoxia (resuscitation after cardiac arrest: n=19, CABG surgery under cardiopulmonary bypass: n=11) were investigated with SPECT 2h p.i. of 185 MBq I-123 IBZM. For semiquant, evaluation transverse slices corrected for attenuation were used to calculate striatal to frontal cortex (S/FC) ratios. In 13/19 pts with cerebral hypoxia due to cardiac arrest IBZM binding was severely reduced after successful resuscitation. 7 died, 5 were in a vegetative state, 1 remained severely disabled. In 6/19 S/FC ratios were normal/mildly reduced, 2 of them had a good outcome, 4 were moderatley disabled. In pts with CABG IBZM binding was preoperatively normal. After hypoxia due to cardiac surgery striatal S/FC ratios decreased slightly, persisting on this level even 6 months after surgery. Neuropsychological/psychiatric testing showed only minor or transient changes in this group of patients. The striatal D2 receptor status seems to be a sensitive indicator for cerebral hypoxia. After hypoxia due to cardiac arrest IBZM results well correlate (in contrast to morphological or SEP findings) with the clinical outcome and thus may serve as early predictor of the individual prognosis. The moderate decline in IBZM binding following CABG surgery suggests mild cerebral hypoxia despite of protective hypothermia. Sensitively indicating cerebral hypoxia changes in the D2 receptor status assessed by IBZM SPECT may serve as a valuable diagnostic tool for testing neuroprotective drugs or modified surgical techniques.

  15. Terguride, a dopamine D(2) partial agonist, as a discriminative stimulus in rats. (United States)

    Yamaguchi, M.; Kimura-Iwasaki, K.; Akai, T.; Nakada, Y.; Nakagawa, H.


    Drug discrimination training with terguride, a 9, 10-transdihydrogenated derivative of lisuride, was carried out using a two-lever food-reinforced procedure (FR 10) in rats, to investigate its influence on central dopaminergic (DA) and serotonergic (5-HT) functions. The terguride (0.05mg/kg, i.p.) discrimination was established within 64 +/- 5 training sessions (mean +/- S.E.) and was stably maintained thereafter. Higher doses of terguride could not be used for discriminative training due to response disruption. In generalization tests with terguride, drug-appropriate responding increased dose-dependently and reached levels of 45 and 99% at 0.01 and 0.05mg/kg i.p. The D(2) agonist lisuride at low doses and the DA autoreceptor agonist (-)-3-PPP substituted for terguride. The DA agonist apomorphine and the 5-HT agonist 5-MeO-DMT produced dose-dependent but incomplete substitution. The D(1) agonist SKF38393, the DA antagonist haloperidol, the D(2) antagonist sulpiride, the D(1) antagonist SCH23390, the 5-HT(1A) agonist 8-OH-DPAT, the 5-HT(1B) agonist m-CPP and the 5-HT(2) agonist DOI were not generalized. In antagonism tests, sulpride completely blocked the terguride-appropriate response, but SCH23390 and the 5-HT antagonist methysergide did not. These results indicate that discriminative stimulus properties of terguride in rats are mediated primarily by activation of receptors with characteristics similar to those of presynaptic D(2) autoreceptors.

  16. Energy Efficient IoT Data Collection in Smart Cities Exploiting D2D Communications (United States)

    Orsino, Antonino; Araniti, Giuseppe; Militano, Leonardo; Alonso-Zarate, Jesus; Molinaro, Antonella; Iera, Antonio


    Fifth Generation (5G) wireless systems are expected to connect an avalanche of “smart” objects disseminated from the largest “Smart City” to the smallest “Smart Home”. In this vision, Long Term Evolution-Advanced (LTE-A) is deemed to play a fundamental role in the Internet of Things (IoT) arena providing a large coherent infrastructure and a wide wireless connectivity to the devices. However, since LTE-A was originally designed to support high data rates and large data size, novel solutions are required to enable an efficient use of radio resources to convey small data packets typically exchanged by IoT applications in “smart” environments. On the other hand, the typically high energy consumption required by cellular communications is a serious obstacle to large scale IoT deployments under cellular connectivity as in the case of Smart City scenarios. Network-assisted Device-to-Device (D2D) communications are considered as a viable solution to reduce the energy consumption for the devices. The particular approach presented in this paper consists in appointing one of the IoT smart devices as a collector of all data from a cluster of objects using D2D links, thus acting as an aggregator toward the eNodeB. By smartly adapting the Modulation and Coding Scheme (MCS) on the communication links, we will show it is possible to maximize the radio resource utilization as a function of the total amount of data to be sent. A further benefit that we will highlight is the possibility to reduce the transmission power when a more robust MCS is adopted. A comprehensive performance evaluation in a wide set of scenarios will testify the achievable gains in terms of energy efficiency and resource utilization in the envisaged D2D-based IoT data collection. PMID:27338385

  17. Energy Efficient IoT Data Collection in Smart Cities Exploiting D2D Communications

    Directory of Open Access Journals (Sweden)

    Antonino Orsino


    Full Text Available Fifth Generation (5G wireless systems are expected to connect an avalanche of “smart” objects disseminated from the largest “Smart City” to the smallest “Smart Home”. In this vision, Long Term Evolution-Advanced (LTE-A is deemed to play a fundamental role in the Internet of Things (IoT arena providing a large coherent infrastructure and a wide wireless connectivity to the devices. However, since LTE-A was originally designed to support high data rates and large data size, novel solutions are required to enable an efficient use of radio resources to convey small data packets typically exchanged by IoT applications in “smart” environments. On the other hand, the typically high energy consumption required by cellular communications is a serious obstacle to large scale IoT deployments under cellular connectivity as in the case of Smart City scenarios. Network-assisted Device-to-Device (D2D communications are considered as a viable solution to reduce the energy consumption for the devices. The particular approach presented in this paper consists in appointing one of the IoT smart devices as a collector of all data from a cluster of objects using D2D links, thus acting as an aggregator toward the eNodeB. By smartly adapting the Modulation and Coding Scheme (MCS on the communication links, we will show it is possible to maximize the radio resource utilization as a function of the total amount of data to be sent. A further benefit that we will highlight is the possibility to reduce the transmission power when a more robust MCS is adopted. A comprehensive performance evaluation in a wide set of scenarios will testify the achievable gains in terms of energy efficiency and resource utilization in the envisaged D2D-based IoT data collection.

  18. The effect of rock particles and D2O replacement on the flow behaviour of ice. (United States)

    Middleton, Ceri A; Grindrod, Peter M; Sammonds, Peter R


    Ice-rock mixtures are found in a range of natural terrestrial and planetary environments. To understand how flow processes occur in these environments, laboratory-derived properties can be extrapolated to natural conditions through flow laws. Here, deformation experiments have been carried out on polycrystalline samples of pure ice, ice-rock and D2O-ice-rock mixtures at temperatures of 263, 253 and 233 K, confining pressure of 0 and 48 MPa, rock fraction of 0-50 vol.% and strain-rates of 5 × 10-7 to 5 × 10-5 s-1 Both the presence of rock particles and replacement of H2O by D2O increase bulk strength. Calculated flow law parameters for ice and H2O-ice-rock are similar to literature values at equivalent conditions, except for the value of the rock fraction exponent, here found to be 1. D2O samples are 1.8 times stronger than H2O samples, probably due to the higher mass of deuterons when compared with protons. A gradual transition between dislocation creep and grain-size-sensitive deformation at the lowest strain-rates in ice and ice-rock samples is suggested. These results demonstrate that flow laws can be found to describe ice-rock behaviour, and should be used in modelling of natural processes, but that further work is required to constrain parameters and mechanisms for the observed strength enhancement.This article is part of the themed issue 'Microdynamics of ice'. © 2016 The Author(s).

  19. Energy Efficient IoT Data Collection in Smart Cities Exploiting D2D Communications. (United States)

    Orsino, Antonino; Araniti, Giuseppe; Militano, Leonardo; Alonso-Zarate, Jesus; Molinaro, Antonella; Iera, Antonio


    Fifth Generation (5G) wireless systems are expected to connect an avalanche of "smart" objects disseminated from the largest "Smart City" to the smallest "Smart Home". In this vision, Long Term Evolution-Advanced (LTE-A) is deemed to play a fundamental role in the Internet of Things (IoT) arena providing a large coherent infrastructure and a wide wireless connectivity to the devices. However, since LTE-A was originally designed to support high data rates and large data size, novel solutions are required to enable an efficient use of radio resources to convey small data packets typically exchanged by IoT applications in "smart" environments. On the other hand, the typically high energy consumption required by cellular communications is a serious obstacle to large scale IoT deployments under cellular connectivity as in the case of Smart City scenarios. Network-assisted Device-to-Device (D2D) communications are considered as a viable solution to reduce the energy consumption for the devices. The particular approach presented in this paper consists in appointing one of the IoT smart devices as a collector of all data from a cluster of objects using D2D links, thus acting as an aggregator toward the eNodeB. By smartly adapting the Modulation and Coding Scheme (MCS) on the communication links, we will show it is possible to maximize the radio resource utilization as a function of the total amount of data to be sent. A further benefit that we will highlight is the possibility to reduce the transmission power when a more robust MCS is adopted. A comprehensive performance evaluation in a wide set of scenarios will testify the achievable gains in terms of energy efficiency and resource utilization in the envisaged D2D-based IoT data collection.

  20. The ultraviolet photodissociation of CS2: the S(1D2) channel. (United States)

    Brouard, M; Campbell, E K; Cireasa, R; Johnsen, A J; Yuen, W-H


    The photodissociation of CS(2) has been investigated using velocity-map ion imaging of the S((1)D(2)) atomic photofragments following excitation at 193 nm and at longer wavelengths close to the S((1)D(2)) channel threshold. The experiments probe regions both above and below the energetic barrier to linearity on the (1)Σ(u) (+)((1)B(2)) potential energy surface. The imaging data in both regions indicate that the electronic angular momentum of the S((1)D(2)) atom products is unpolarized, but also reveal different dissociation dynamics in the two regions. Excitation above the barrier to linearity yields an inverted CS((1)Σ(+)) vibrational population distribution, whereas the long-wavelength state-to-state results following excitation below the barrier reveal CS((1)Σ(+))(v, J) coproduct state distributions which are consistent with a statistical partitioning of the energy. Below the barrier, photofragment excitation spectra point to an enhancement of the singlet channel for K = 1, relative to K = 0, where K is the projection of the angular momentum along the principal axis, in agreement with previous work. However, the CS cofragment product state distributions are found to be insensitive to K. It is proposed that dissociation below the barrier to linearity occurs primarily on a surface with a significant potential energy well and without an exit channel barrier, such as that for the ground electronic state. However, oscillatory structure is also observed in the kinetic energy release distributions, which is shown to be consistent with a mapping of parent molecule bending motion. This could indicate the operation of competing direct and indirect dissociation mechanisms below the barrier to linearity. © 2012 American Institute of Physics

  1. Surface Roughness Optimization Using Taguchi Method of High Speed End Milling For Hardened Steel D2 (United States)

    Hazza Faizi Al-Hazza, Muataz; Ibrahim, Nur Asmawiyah bt; Adesta, Erry T. Y.; Khan, Ahsan Ali; Abdullah Sidek, Atiah Bt.


    The main challenge for any manufacturer is to achieve higher quality of their final products with maintains minimum machining time. In this research final surface roughness analysed and optimized with maximum 0.3 mm flank wear length. The experiment was investigated the effect of cutting speed, feed rate and depth of cut on the final surface roughness using D2 as a work piece hardened to 52-56 HRC, and coated carbide as cutting tool with higher cutting speed 120-240 mm/min. The experiment has been conducted using L9 design of Taguchi collection. The results have been analysed using JMP software.

  2. SANS contrast in iota-carrageenan gels and solutions in D2O

    DEFF Research Database (Denmark)

    Mischenko, N.; Denef, B.; Mortensen, K.


    SANS of Na+-iota-carrageenan in D2O/saline solutions was measured as a function of concentration, temperature and type of counterions (K+ or Na+). High and low scattering-contrasted gels and solutions were detected. High contrast is caused by aggregation of low-hydrated chains at high concentration...... of carrageenan in the presence of gel-promoting counterions. The aggregates do not disappear at 60 degrees C, although at this temperature the molecules should partially lose their ordered conformation. The network formation, observed by SANS, does not happen in high-contrast system immediately after cooling...

  3. Spatiotemporal Imaging of Ultrafast Molecular Motion: Collapse and Revival of the D2+ Nuclear Wave Packet (United States)

    Ergler, Th.; Rudenko, A.; Feuerstein, B.; Zrost, K.; Schröter, C. D.; Moshammer, R.; Ullrich, J.


    We report on a real-time imaging of the ultrafast D2+ rovibrational nuclear wave-packet motion performed using a combination of a pump-probe setup with 7 fs laser pulses and a “reaction-microscope” spectrometer. We observe fast dephasing (collapse) of the vibrational wave packet and its subsequent revival and prove rotational excitation in ultrashort laser pulses. Channel-selective Fourier analysis of the wave packet’s long-term (˜3000fs) evolution allows us to resolve its individual constituents, revealing unique information on the mechanisms of strong-field ionization and dissociation.

  4. Quantum wave packet study of S( 1D) + D 2 → SD + D reaction (United States)

    Bulut, Niyazi; Gogtas, Fahrettin; Akpinar, Sinan


    S( 1D) + D 2 → SD + D reaction has been studied by using a time-dependent quantum real wave packet method. State-to-state and state-to-all reactive scattering probabilities for a broad range of energy are calculated at zero total angular momentum. The state-to-state probabilities show many sharp peaks that ascribed to reactive scattering resonances. The probabilities for J > 0 are estimated from accurately computed J = 0 probabilities by using J-shifting approximation. The integral cross-sections are calculated for a large energy range.

  5. 75 FR 76758 - Program for Allocation of Regulatory Responsibilities Pursuant to Rule 17d-2; Order Approving and... (United States)


    ... Declaring Effective a Plan for the Allocation of Regulatory Responsibilities Between BATS Exchange, Inc... with the Securities and Exchange Commission (``Commission'' or ``SEC'') a plan for the allocation of... 17d-2 agreement.\\10\\ \\10\\ See Paragraph 1 of the proposed 17d-2 Plan; see e.g., Securities Exchange...

  6. Cp2TiCl/D2O/Mn, a formidable reagent for the deuteration of organic compounds

    Directory of Open Access Journals (Sweden)

    Antonio Rosales


    Full Text Available Cp2TiCl/D2O/Mn is an efficient combination, sustainable and cheap reagent that mediates the D-atom transfer from D2O to different functional groups and can contribute to the synthesis of new deuterated organic compounds under friendly experimental conditions and with great economic advantages.

  7. Adsorbed Layers of D2, H2, O2, and 3He on Graphite Studied by Neutron Scattering

    DEFF Research Database (Denmark)

    Nielsen, Mourits; McTague, J. P.; Ellenson, W. D.


    The phase diagrams of adsorbed monolayers of D2, H2, O2, and 3He on graphite have been measured by neutron diffraction. H2 and D2-layers have a registered √3 structure at low coverages, and at monolayer completion they have a dense triangular structure, which is incommensurate with the substrate....

  8. Leptin Increases Striatal Dopamine D2 Receptor Binding in Leptin-Deficient Obese (ob/ob) Mice

    Energy Technology Data Exchange (ETDEWEB)

    Pfaffly, J.; Michaelides, M.; Wang, G-J.; Pessin, J.E.; Volkow, N.D.; Thanos, P.K.


    Peripheral and central leptin administration have been shown to mediate central dopamine (DA) signaling. Leptin-receptor deficient rodents show decreased DA D2 receptor (D2R) binding in striatum and unique DA profiles compared to controls. Leptin-deficient mice show increased DA activity in reward-related brain regions. The objective of this study was to examine whether basal D2R-binding differences contribute to the phenotypic behaviors of leptin-deficient ob/ob mice, and whether D2R binding is altered in response to peripheral leptin treatment in these mice. Leptin decreased body weight, food intake, and plasma insulin concentration in ob/ob mice but not in wild-type mice. Basal striatal D2R binding (measured with autoradiography [{sup 3}H] spiperone) did not differ between ob/ob and wild-type mice but the response to leptin did. In wild-type mice, leptin decreased striatal D2R binding, whereas, in ob/ob mice, leptin increased D2R binding. Our findings provide further evidence that leptin modulates D2R expression in striatum and that these effects are genotype/phenotype dependent.

  9. Gamma-hydroxybutyrate receptor function determined by stimulation of rubidium and calcium movements from NCB-20 neurons. (United States)

    Kemmel, V; Taleb, O; Andriamampandry, C; Aunis, D; Maitre, M


    Gamma-Hydroxybutyrate is derived from GABA in brain and plays specific functional roles in the CNS. It is thought to exert a tonic inhibitory control on dopamine and GABA release in certain brain areas, through specific gamma-hydroxybutyrate receptors. Apart from modifying certain calcium currents, the specific transduction mechanism induced by stimulation of gamma-hydroxybutyrate receptors remains largely unknown. We investigated the possible contribution of K(+) channels to the hyperpolarization phenomena generally induced by gamma-hydroxybutyrate in brain, by monitoring (86)Rb(+) movements in a neuronal cell line (NCB-20 cells), which expresses gamma-hydroxybutyrate receptors. Physiological concentrations of gamma-hydroxybutyrate (5-25 microM) induce a slow efflux of (86)Rb(+), which peaks at 5-15 min and returns to baseline levels 20 min later after constant stimulation. This effect can be reproduced by the gamma-hydroxybutyrate receptor agonist NCS-356 and blocked by the gamma-hydroxybutyrate receptor antagonist 6,7,8,9-tetrahydro-5-[H]-benzocycloheptene-5-ol-4-ylidene. The GABA(B) receptor antagonist CGP 55845 has no effect on gamma-hydroxybutyrate-induced (86)Rb(+) efflux. The pharmacology of this gamma-hydroxybutyrate-dependent efflux of (86)Rb(+) is in favor of the involvement of tetraethylammonium and charybdotoxin insensitive, apamin sensitive Ca(2+) activated K(+) channels, identifying them as small conductance calcium activated channels. We demonstrated a gamma-hydroxybutyrate dose-dependent entry of calcium ions into NCB-20 neuroblastoma cells at resting potential. Electrophysiological data showed that this Ca(2+) entry corresponded mainly to a left-hand shift of the current/voltage relation of the T-type calcium channel. This process must at least partially trigger small conductance calcium activated channel activation leading to gamma-hydroxybutyrate-induced hyperpolarization.

  10. High-pressure phase transition of alkali metal-transition metal deuteride Li2PdD2 (United States)

    Yao, Yansun; Stavrou, Elissaios; Goncharov, Alexander F.; Majumdar, Arnab; Wang, Hui; Prakapenka, Vitali B.; Epshteyn, Albert; Purdy, Andrew P.


    A combined theoretical and experimental study of lithium palladium deuteride (Li2PdD2) subjected to pressures up to 50 GPa reveals one structural phase transition near 10 GPa, detected by synchrotron powder x-ray diffraction, and metadynamics simulations. The ambient-pressure tetragonal phase of Li2PdD2 transforms into a monoclinic C2/m phase that is distinct from all known structures of alkali metal-transition metal hydrides/deuterides. The structure of the high-pressure phase was characterized using ab initio computational techniques and from refinement of the powder x-ray diffraction data. In the high-pressure phase, the PdD2 complexes lose molecular integrity and are fused to extended [PdD2]∞ chains. The discovered phase transition and new structure are relevant to the possible hydrogen storage application of Li2PdD2 and alkali metal-transition metal hydrides in general.

  11. Imaging of dopamine transporters and D2 receptors in patients with Parkinson's disease and multiple system atrophy

    DEFF Research Database (Denmark)

    Knudsen, G M; Karlsborg, M; Thomsen, G


    of the striatonigral type (MSA) and healthy subjects. METHODS: SPECT measurements of the dopamine transporter (DAT) were done with 123I-beta-CIT, while for determination of the dopamine D2-like receptors (D2), 123I-epidepride was used. Clinical evaluation and SPECT scans were carried out in 14 patients with IPD, eight...... asymmetry than MSA patients. Striatal D2 binding did not differ significantly between patients and healthy controls but the ratio between caudate DAT and D2 binding was significantly higher in patients with IPD than in those with MSA, even when disease severity was taken into account. CONCLUSION: Patients...... diagnostic information, since the ratio between DAT and D2 receptor binding is significantly higher in IPD than in MSA...

  12. Relationship between Dose, Drug Levels, and D2 Receptor Occupancy for the Atypical Antipsychotics Risperidone and Paliperidone (United States)

    Votaw, J. R.; Ritchie, J.; Howell, L. L.


    Blockade of D2 family dopamine receptors (D2Rs) is a fundamental property of antipsychotics, and the degree of striatal D2R occupancy has been related to antipsychotic and motor effects of these drugs. Recent studies suggest the D2R occupancy of antipsychotics may differ in extrastriatal regions compared with the dorsal striatum. We studied this issue in macaque monkeys by using a within-subjects design. [18F]fallypride positron emission tomography scans were obtained on four different doses of risperidone and paliperidone (the 9-OH metabolite of risperidone) and compared with multiple off-drug scans in each animal. The half-life of the two drugs in these monkeys was determined to be between 3 and 4 h, and drug was administered by a constant infusion through an intragastric catheter. The D2R occupancy of antipsychotic was determined in the caudate, putamen, ventral striatum, and four prefrontal and temporal cortical regions and was related to serum and cerebrospinal fluid drug levels. Repeated 2-week treatment with risperidone or paliperidone did not produce lasting changes in D2R binding potential in any region examined. As expected, D2R binding potential was highest in the caudate and putamen and was approximately one-third that level in the ventral striatum and 2% of that level in the cortical regions. We found dose-dependent D2R occupancy for both risperidone and paliperidone in both basal ganglia and cortical regions of interest. We could not find evidence of regional variation in D2R occupancy of either drug. Comparison of D2R occupancy and serum drug levels supports a target of 40 to 80 ng/ml active drug for these two atypical antipsychotics. PMID:22214649

  13. A novel null homozygous mutation confirms CACNA2D2 as a gene mutated in epileptic encephalopathy.

    Directory of Open Access Journals (Sweden)

    Tommaso Pippucci

    Full Text Available Contribution to epileptic encephalopathy (EE of mutations in CACNA2D2, encoding α2δ-2 subunit of Voltage Dependent Calcium Channels, is unclear. To date only one CACNA2D2 mutation altering channel functionality has been identified in a single family. In the same family, a rare CELSR3 polymorphism also segregated with disease. Involvement of CACNA2D2 in EE is therefore not confirmed, while that of CELSR3 is questionable. In a patient with epilepsy, dyskinesia, cerebellar atrophy, psychomotor delay and dysmorphic features, offspring to consanguineous parents, we performed whole exome sequencing (WES for homozygosity mapping and mutation detection. WES identified extended autozygosity on chromosome 3, containing two novel homozygous candidate mutations: c.1295delA (p.Asn432fs in CACNA2D2 and c.G6407A (p.Gly2136Asp in CELSR3. Gene prioritization pointed to CACNA2D2 as the most prominent candidate gene. The WES finding in CACNA2D2 resulted to be statistically significant (p = 0.032, unlike that in CELSR3. CACNA2D2 homozygous c.1295delA essentially abolished α2δ-2 expression. In summary, we identified a novel null CACNA2D2 mutation associated to a clinical phenotype strikingly similar to the Cacna2d2 null mouse model. Molecular and statistical analyses together argued in favor of a causal contribution of CACNA2D2 mutations to EE, while suggested that finding in CELSR3, although potentially damaging, is likely incidental.

  14. The vibrational Stokes shift of water (HOD in D2O) (United States)

    Wang, Zhaohui; Pang, Yoonsoo; Dlott, Dana D.


    The vibrational Stokes shift of the OH stretching transition νOH of water is the shift between the ground-state absorption and the excited-state (v=1) emission. A recent measurement on HOD in D2O solvent [S. Woutersen and H. J. Bakker, Phys. Rev. Lett. 83, 2077 (1999)] of a 70 cm-1 redshift, and a subsequent calculation of a 57 cm-1 redshift using equilibrium molecular dynamics simulations [C. P. Lawrence and J. L. Skinner, J. Chem. Phys. 117, 8847 (2002)] were in good agreement. We now report extensive measurements of the vibrational Stokes shift in HOD/D2O using an ultrafast IR pump, Raman probe method. The vibrational Stokes shift is seen to depend on the pump pulse frequency and on time delay; by varying these parameters it can be made to range from 112 to -32 cm-1 (negative values indicate a blueshift in the excited state). The equilibrium vibrational Stokes shift is actually a negative rather than a positive quantity. Possible reasons for the disagreement between experiment and theory are briefly discussed.

  15. Two-way DF relaying assisted D2D communication: ergodic rate and power allocation (United States)

    Ni, Yiyang; Wang, Yuxi; Jin, Shi; Wong, Kai-Kit; Zhu, Hongbo


    In this paper, we investigate the ergodic rate for a device-to-device (D2D) communication system aided by a two-way decode-and-forward (DF) relay node. We first derive closed-form expressions for the ergodic rate of the D2D link under asymmetric and symmetric cases, respectively. We subsequently discuss two special scenarios including weak interference case and high signal-to-noise ratio case. Then we derive the tight approximations for each of the considered scenarios. Assuming that each transmitter only has access to its own statistical channel state information (CSI), we further derive closed-form power allocation strategy to improve the system performance according to the analytical results of the ergodic rate. Furthermore, some insights are provided for the power allocation strategy based on the analytical results. The strategies are easy to compute and require to know only the channel statistics. Numerical results show the accuracy of the analysis results under various conditions and test the availability of the power allocation strategy.

  16. On mode selection and power control for uplink D2D communication in cellular networks

    KAUST Repository

    Ali, Konpal S.


    Device-to-device (D2D) communication enables users lying in close proximity to bypass the cellular base station (BS) and transmit to one another directly. This offloads traffic from the cellular network, improves spatial frequency reuse and energy efficiency in the network. We present a comprehensive and tractable analytical framework for D2D-enabled uplink cellular networks with two different flexible mode-selection schemes. The power-control cutoff thresholds of the two communication modes have been decoupled unlike past work on the subject. We find that for a given network, an optimal value exists not only for the biased mode selection criterion, but also for r, the ratio of the power-control cutoff thresholds of the two communication modes, which maximizes spatial spectral efficiency. Also, r turns out to be a more robust parameter for optimizing network performance. Further, it is shown that the second scheme, which prioritizes spatial frequency reuse over the per-user achievable performance compared to the first scheme, achieves almost the same overall network performance; thereby trading per user performance to serve a larger number of users.

  17. Infrared Spectroscopy of the H2/HD/D2-O2 Van Der Waals Complexes (United States)

    Raston, Paul; Bunn, Hayley


    Hydrogen is the most abundant element in the universe and oxygen is the third, so understanding the interaction between the two in their different forms is important to understanding astrochemical processes. The interaction between H2 and O2 has been explored in low energy scattering experiments and by far infrared synchrotron spectroscopy of the van der Waals complex. The far infrared spectra suggest a parallel stacked average structure with seven bound rotationally excited states. Here, we present the far infrared spectrum of HD/D2-O2 and the mid infrared spectrum of H2-O2 at 80 K, recorded at the infrared beamline facility of the Australian Synchrotron. We observed 'sharp' peaks in the mid infrared region, corresponding to the end over end rotation of H2-O2, that are comparatively noisier than analogous peaks in the far infrared where the synchrotron light is brightest. The larger reduced mass of HD and D2 compared to H2 is expected to result in more rotational bound states and narrower bands. The latest results in our ongoing efforts to explore this system will be presented. Y. Kalugina, et al., Phys. Chem. Chem. Phys. 14, 16458 (2012) S. Chefdeville et al. Science 341, 1094 (2013) H. Bunn et al. ApJ 799, 65 (2015)

  18. D retention in Be exposed to fusion relevant mixed species D2−He plasma

    Directory of Open Access Journals (Sweden)

    M.J. Baldwin


    Full Text Available He admixture to D2 plasma incident on Be targets is used to study the influence of a fusion-ash relevant He concentration on D retention. A variation of exposure parameters such as He ion fraction: 0.02 ≤ α ≤ 0.1, exposure temperature: 330 ≤ Texp ≤ 650 K, ion-fluence: 5 × 1024 ≤ Φ ≤ 1 × 1027 m−2 and energy: 40 ≤ Ei ≤ 90 eV, are explored. Results are compared to D retention values in Be observed in D2 plasma (α=0. With α=0.1, a factor ∼3 reduction in D retention is noted for exposure at ∼300 K, but is less as Texp approaches ∼473 K, and not apparent above 473 K. The reduction is caused by the ability of He to hinder D saturation in low-release-temperature supersaturated binding states.

  19. A Precision Measurement of the Neutron Twist-3 Matrix Element $d_2^n$: Probing Color Forces

    CERN Document Server

    Posik, M; Parno, D S; Allada, K; Armstrong, W; Averett, T; Benmokhtar, F; Bertozzi, W; Camsonne, A; Canan, M; Cates, G D; Chen, C; Chen, J -P; Choi, S; Chudakov, E; Cusanno, F; Dalton, M M; Deconinck, W; de Jager, C W; Deng, X; Deur, A; Dutta, C; Fassi, L El; Franklin, G B; Friend, M; Gao, H; Garibaldi, F; Gilad, S; Gilman, R; Glamazdin, O; Golge, S; Gomez, J; Guo, L; Hansen, O; Higinbotham, D W; Holmstrom, T; Huang, J; Hyde, C; Ibrahim, H F; Jiang, X; Jin, G; Katich, J; Kelleher, A; Kolarkar, A; Korsch, W; Kumbartzki, G; LeRose, J J; Lindgren, R; Liyanage, N; Long, E; Lukhanin, A; Mamyan, V; McNulty, D; Meziani, Z -E; Michaels, R; Mihovilovič, M; Moffit, B; Muangma, N; Nanda, S; Narayan, A; Nelyubin, V; Norum, B; Nuruzzaman,; Oh, Y; Peng, J C; Qian, X; Qiang, Y; Rakhman, A; Riordan, S; Saha, A; Sawatzky, B; Shabestari, M H; Shahinyan, A; Širca, S; Solvignon, P; Subedi, R; Sulkosky, V; Tobias, A; Troth, W; Wang, D; Wang, Y; Wojtsekhowski, B; Yan, X; Yao, H; Ye, Y; Ye, Z; Yuan, L; Zhan, X; Zhang, Y; Zhang, Y -W; Zhao, B; Zheng, X


    Double-spin asymmetries and absolute cross sections were measured at large Bjorken $x$ (0.25 $ \\le x \\le $ 0.90), in both the deep-inelastic and resonance regions, by scattering longitudinally polarized electrons at beam energies of 4.7 and 5.9 GeV from a transversely and longitudinally polarized $^3$He target. In this dedicated experiment, the spin structure function $g_2$ on $^3$He was determined with precision at large $x$, and the neutron twist-three matrix element $d_2^n$ was measured at $\\left$ of 3.21 and 4.32 GeV$^2$/$c^2$, with an absolute precision of about $10^{-5}$. Our results are found to be in agreement with lattice QCD calculations and resolve the disagreement found with previous data at $\\left =$ 5 GeV$^2$/$c^2$. Combining $d_2^n$ and a newly extracted twist-four matrix element, $f_2^n$, the average neutron color electric and magnetic forces were extracted and found to be of opposite sign and about 60 MeV/fm in magnitude.

  20. High affinity dopamine D2 receptor radioligands. 1. Regional rat brain distribution of iodinated benzamides

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, R.M.; Ansari, M.S.; de Paulis, T.; Schmidt, D.E.; Clanton, J.A.; Smith, H.E.; Manning, R.G.; Gillespie, D.; Ebert, M.H. (Vanderbilt University School of Medicine, Nashville, TN (USA))


    Five 125I-labeled substituted benzamides, which are close structural analogues of (S)-sulpiride, eticlopride, and isoremoxipride, were evaluated for their selective in vivo uptake into dopamine D2 receptor rich tissue of the rat brain. Iodopride (KD 0.88 nM), an iodine substituted benzamide structurally related to sulpiride, displayed a maximal striatum: cerebellar uptake ratio of 7.6. Demonstration of saturation of the receptor with (125I)iodopride in striatum required uptake in frontal cortex to be used, rather than cerebellar uptake, to define nonspecific binding. Two other ligands structurally related to eticlopride, iclopride (KD 0.23 nM) and itopride (KD 0.16 nM), displayed maximal striatal: cerebellar uptake ratios of 9.8 and 3.3, respectively. The most potent ligands, epidepride (KD 0.057 nM) and ioxipride (KD 0.070 nM) showed striatal:cerebellar uptake ratios of 234 and 65, respectively. The observed uptake ratios correlated poorly with the affinity constants for the dopamine D2 receptor alone, but were highly correlated (r = 0.92) with the product of the receptor dissociation constant (KD) and the apparent lipophilicity (kw), as determined by reverse-phase HPLC at pH 7.5. Total striatal uptake also appeared dependent on lipophilicity, with maximal uptake occurring for ligands having log kw 2.4-2.8.

  1. The FLO Diffusive 1D-2D Model for Simulation of River Flooding

    Directory of Open Access Journals (Sweden)

    Costanza Aricò


    Full Text Available An integrated 1D-2D model for the solution of the diffusive approximation of the shallow water equations, named FLO, is proposed in the present paper. Governing equations are solved using the MArching in Space and Time (MAST approach. The 2D floodplain domain is discretized using a triangular mesh, and standard river sections are used for modeling 1D flow inside the section width occurring with low or standard discharges. 1D elements, inside the 1D domain, are quadrilaterals bounded by the trace of two consecutive sections and by the sides connecting their extreme points. The water level is assumed to vary linearly inside each quadrilateral along the flow direction, but to remain constant along the direction normal to the flow. The computational cell can share zero, one or two nodes with triangles of the 2D domain when lateral coupling occurs and more than two nodes in the case of frontal coupling, if the corresponding section is at one end of the 1D channel. No boundary condition at the transition between the 1D-2D domain has to be solved, and no additional variable has to be introduced. Discontinuities arising between 1D and 2D domains at 1D sections with a top width smaller than the trace of the section are properly solved without any special restriction on the time step.

  2. Tridimensional personalities and polymorphism of dopamine D2 receptor among heroin addicts. (United States)

    Teh, Lay K; Izuddin, Abu F; M H, Fazleen H; Zakaria, Zainul A; Salleh, Mohd Zaki


    Drug addiction is a multifactorial disorder. Researchers have posited that an individual's inherited behavioral propensity or temperament contributes to the disorder by shaping a personality strongly linked with the risk of drug abuse. Further, they hypothesize that the polymorphism of dopamine D2 receptor increases the susceptibility to and severity of addiction. We, therefore, investigated possible associations between dopamine D2 receptor (DRD2) and personality traits among intravenous heroin addicts. We assessed 93 intravenous heroin addicts and controls using Diagnostic and Statistical Manual, Fourth Edition (DSM-IV) and the Tridimensional Personality Questionnaire (TPQ). We confirmed drug-dependence status using a questionnaire based on DSM-IV criteria. We extracted DNA from the subjects' whole blood and genotyped it for DRD2 allelic variants. Genotype analysis showed a significantly higher frequency for the TaqIA polymorphism among the addicts (69.9%) compared to control subjects (42.6%; Fisher's exact χ(2), p personality traits but lower scores for reward dependence (RD) when compared to control subjects. The environmental cues are different for the addicts, and the healthy university students we used as controls. We recommend that researchers employ a gene-environment interaction approach to study factors associated with addictive behaviors in future studies. Taq1A may be implicated for an increased vulnerability to addiction. Screening of this marker might be useful for identifying individuals at risk of addiction.

  3. Distinct target size of dopamine D-1 and D-2 receptors in rat striatum. (United States)

    Nielsen, M; Klimek, V; Hyttel, J


    Frozen rat striatal tissue was exposed to 10 MeV electrons from a linear accelerator. Based on the theory of target size analysis, the molecular weights of dopamine D-1 receptors (labelled by 3H-piflutixol) and dopamine D-2 receptors (labelled by 3H-spiroperidol) were 79,500 daltons and 136,700 daltons, respectively. The size of the dopamine-stimulated adenylate cyclase was 202,000 daltons. The estimated molecular sizes were deduced by reference to proteins with known molecular weights which were irradiated in parallel. The results showed that the molecular entities for 3H-piflutixol binding and 3H-spiroperidol binding were not identical. The present results do not allow conclusions as to whether D-1 and D-2 receptors are two distinct proteins in the membrane, or whether the receptors are located on the same protein. In the latter case the binding of 3H-spiroperidol needs the presence of a second molecule.

  4. Role of Kv1 potassium channels in regulating dopamine release and presynaptic D2 receptor function.

    Directory of Open Access Journals (Sweden)

    Philippe Martel

    Full Text Available Dopamine (DA release in the CNS is critical for motor control and motivated behaviors. Dysfunction of its regulation is thought to be implicated in drug abuse and in diseases such as schizophrenia and Parkinson's. Although various potassium channels located in the somatodendritic compartment of DA neurons such as G-protein-gated inward rectifying potassium channels (GIRK have been shown to regulate cell firing and DA release, little is presently known about the role of potassium channels localized in the axon terminals of these neurons. Here we used fast-scan cyclic voltammetry to study electrically-evoked DA release in rat dorsal striatal brain slices. We find that although G-protein-gated inward rectifying (GIRK and ATP-gated (K(ATP potassium channels play only a minor role, voltage-gated potassium channels of the Kv1 family play a major role in regulating DA release. The use of Kv subtype-selective blockers confirmed a role for Kv1.2, 1.3 and 1.6, but not Kv1.1, 3.1, 3.2, 3.4 and 4.2. Interestingly, Kv1 blockers also reduced the ability of quinpirole, a D2 receptor agonist, to inhibit evoked DA overflow, thus suggesting that Kv1 channels also regulate presynaptic D2 receptor function. Our work identifies Kv1 potassium channels as key regulators of DA release in the striatum.

  5. HCl+, H2Cl+, DCl+, D2Cl+ dissociative recombination, 300-500 K (United States)

    Miller, Thomas M.; Wiens, Justin P.; Shuman, Nicholas S.; Viggiano, Albert A.


    We have used a flowing afterglow Langmuir probe apparatus to measure dissociative recombination (DR) rate coefficients at 300-500 K for HCl+, H2Cl+, DCl+, and D2Cl+. For 300 K, we find 7.7 x 10-8 cm3/s (HCl+) , 2.6 x 10-7 cm3/s (H2Cl+) , and 1.1 x 10-7 cm3/s (D2Cl+) , each with about 35% accuracy. The DR rate coefficient for DCl+ is too slow for us to measure, especially in the face of dealing with mixed H/D species formed in apparatus feedlines when introducing DCl. DR rate coefficients are needed in modeling chlorinated species in diffuse interstellar molecular clouds,1 though at much lower temperatures than we can reach. Cl+ exists in diffuse clouds because IE(Cl) exothermic to form HCl+ in collision with H2, and a second collision is exothermic to yield H2Cl+. Storage ring experiments2 should yield product branching for the DR reactions. The reaction cycle is repeated from Cl neutrals produced in the DR process. Supported by Air Force Office of Scientific Research (AFOSR-2303EP).

  6. Coupled 1D-2D hydrodynamic inundation model for sewer overflow: Influence of modeling parameters

    Directory of Open Access Journals (Sweden)

    Adeniyi Ganiyu Adeogun


    Full Text Available This paper presents outcome of our investigation on the influence of modeling parameters on 1D-2D hydrodynamic inundation model for sewer overflow, developed through coupling of an existing 1D sewer network model (SWMM and 2D inundation model (BREZO. The 1D-2D hydrodynamic model was developed for the purpose of examining flood incidence due to surcharged water on overland surface. The investigation was carried out by performing sensitivity analysis on the developed model. For the sensitivity analysis, modeling parameters, such as mesh resolution Digital Elevation Model (DEM resolution and roughness were considered. The outcome of the study shows the model is sensitive to changes in these parameters. The performance of the model is significantly influenced, by the Manning's friction value, the DEM resolution and the area of the triangular mesh. Also, changes in the aforementioned modeling parameters influence the Flood characteristics, such as the inundation extent, the flow depth and the velocity across the model domain.

  7. Emotion Dysregulation and Amygdala Dopamine D2-type Receptor Availability in Methamphetamine Users (United States)

    Okita, Kyoji; Ghahremani, Dara G.; Payer, Doris E.; Robertson, Chelsea L.; Dean, Andy C.; Mandelkern, Mark A.; London, Edythe D.


    Background Individuals who use methamphetamine chronically exhibit emotional and dopaminergic neurochemical deficits. Although the amygdala has an important role in emotion processing and receives dopaminergic innervation, little is known about how dopamine transmission in this region contributes to emotion regulation. This investigation aimed to evaluate emotion regulation in subjects who met DSM-IV criteria for methamphetamine dependence, and to test for a relationship between self-reports of difficulty in emotion regulation and D2-type dopamine receptor availability in the amygdala. Method Ninety-four methamphetamine-using and 102 healthy-control subjects completed the Difficulties in Emotion Regulation Scale (DERS); 33 of those who used methamphetamine completed the Addiction Severity Index (ASI). A subset of 27 methamphetamine-group and 20 control-group subjects completed positron emission tomography with [18F]fallypride to assay amygdala D2-type dopamine receptor availability, measured as binding potential (BPND). Results The methamphetamine group scored higher than the control group on the DERS total score (p dopamine receptors in the amygdala contribute to emotion regulation in both healthy and methamphetamine-using subjects. PMID:26880595

  8. A Thy1-CFP DBA/2J mouse line with cyan fluorescent protein expression in retinal ganglion cells. (United States)

    Raymond, Iona D; Pool, Angela L; Vila, Alejandro; Brecha, Nicholas C


    A DBA/2J (D2) transgenic mouse line with cyan fluorescent protein (CFP) reporter expression in ganglion cells was developed for the analysis of ganglion cells during progressive glaucoma. The Thy1-CFP D2 (CFP-D2) line was created by congenically breeding the D2 line, which develops pigmentary glaucoma, and the Thy1-CFP line, which expresses CFP in ganglion cells. Microsatellite marker analysis of CFP-D2 progeny verified the genetic inclusion of the D2 isa and ipd loci. Specific mutations within these loci lead to dysfunctional melanosomal proteins and glaucomatous phenotype in D2 mice. Polymerase chain reaction analysis confirmed the inclusion of the Thy1-CFP transgene. CFP-fluorescent ganglion cells, 6-20 microm in diameter, were distributed in all retinal regions, CFP processes were throughout the inner plexiform layer, and CFP-fluorescent axons were in the fiber layer and optic nerve head. Immunohistochemistry with antibodies to ganglion cell markers NF-L, NeuN, Brn3a, and SMI32 was used to confirm CFP expression in ganglion cells. Immunohistochemistry with antibodies to amacrine cell markers HPC-1 and ChAT was used to confirm weak CFP expression in cholinergic amacrine cells. CFP-D2 mice developed a glaucomatous phenotype, including iris disease, ganglion cell loss, attrition of the fiber layer, and elevated intraocular pressure. A CFP-D2 transgenic line with CFP-expressing ganglion cells was developed, which has (1) a predominantly D2 genetic background, (2) CFP-expressing ganglion cells, and (3) age-related progressive glaucoma. This line will be of value for experimental studies investigating ganglion cells and their axons in vivo and in vitro during the progressive development of glaucoma.

  9. Correlations between potassium, rubidium and cesium ({sup 133}Cs and {sup 137}Cs) in sporocarps of Suillus variegatus in a Swedish boreal forest

    Energy Technology Data Exchange (ETDEWEB)

    Vinichuk, M., E-mail: Mykhailo.Vinichuk@slu.s [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Department of Ecology, Zhytomyr State Technological University, 103 Cherniakhovsky Str., 10005 Zhytomyr (Ukraine); Rosen, K.; Johanson, K.J. [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Dahlberg, A. [Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, P.O. Box 7026, 750 07 Uppsala (Sweden)


    An analysis of sporocarps of ectomycorrhizal fungi Suillus variegatus assessed whether cesium ({sup 133}Cs and {sup 137}Cs) uptake was correlated with potassium (K) or rubidium (Rb) uptake. The question was whether intraspecific correlations of Rb, K and {sup 133}Cs mass concentrations with {sup 137}Cs activity concentrations in sporocarps were higher within, rather than among, different fungal species, and if genotypic origin of sporocarps within a population affected uptake and correlation. Sporocarps (n = 51) from a Swedish forest population affected by the fallout after the Chernobyl accident were studied. The concentrations were 31.9 {+-} 6.79 g kg{sup -1} for K (mean {+-} SD, dwt), 0.40 {+-} 0.09 g kg{sup -1} for Rb, 8.7 {+-} 4.36 mg kg{sup -1} for {sup 133}Cs and 63.7 {+-} 24.2 kBq kg{sup -1} for {sup 137}Cs. The mass concentrations of {sup 133}Cs correlated with {sup 137}Cs activity concentrations (r = 0.61). There was correlation between both {sup 133}Cs concentrations (r = 0.75) and {sup 137}Cs activity concentrations (r = 0.44) and Rb, but the {sup 137}Cs/{sup 133}Cs isotopic ratio negatively correlated with Rb concentration. Concentrations of K and Rb were weakly correlated (r = 0.51). The {sup 133}Cs mass concentrations, {sup 137}Cs activity concentrations and {sup 137}Cs/{sup 133}Cs isotopic ratios did not correlate with K concentrations. No differences between, within or, among genotypes in S. variegatus were found. This suggested the relationships between K, Rb, {sup 133}Cs and {sup 137}Cs in sporocarps of S. variegatus is similar to other fungal species. - Highlights: {yields} We studied uptake of Cs ({sup 133}Cs and {sup 137}Cs), K and Rb by Suillus variegates sporocarps. {yields} Genotypic origin of fungus did not affect uptake of studied elements (isotopes). {yields} Genotypic origin did not affect correlation between Cs ({sup 133}Cs and {sup 137}Cs), K and Rb.

  10. Dopamine D2 Receptors Modulate Pyramidal Neurons in Mouse Medial Prefrontal Cortex through a Stimulatory G-Protein Pathway. (United States)

    Robinson, Sarah E; Sohal, Vikaas S


    Dopaminergic modulation of prefrontal cortex (PFC) is thought to play key roles in many cognitive functions and to be disrupted in pathological conditions, such as schizophrenia. We have previously described a phenomenon whereby dopamine D2 receptor (D2R) activation elicits afterdepolarizations (ADPs) in subcortically projecting (SC) pyramidal neurons within L5 of the PFC. These D2R-induced ADPs only occur following synaptic input, which activates NMDARs, even when the delay between the synaptic input and ADPs is relatively long (e.g., several hundred milliseconds). Here, we use a combination of electrophysiological, optogenetic, pharmacological, transgenic, and chemogenetic approaches to elucidate cellular mechanisms underlying this phenomenon in male and female mice. We find that knocking out D2Rs eliminates the ADP in a cell-autonomous fashion, confirming that this ADP depends on D2Rs. Hyperpolarizing current injection, but not AMPA receptor blockade, prevents synaptic stimulation from facilitating D2R-induced ADPs, suggesting that this phenomenon depends on the recruitment of voltage-dependent currents (e.g., NMDAR-mediated Ca 2+ influx) by synaptic input. Finally, the D2R-induced ADP is blocked by inhibitors of cAMP/PKA signaling, insensitive to pertussis toxin or β-arrestin knock-out, and mimicked by G s -DREADD stimulation, suggesting that D2R activation elicits the ADP by stimulating cAMP/PKA signaling. These results show that this unusual physiological phenomenon, in which D2Rs enhance cellular excitability in a manner that depends on synaptic input, is mediated at the cellular level through the recruitment of signaling pathways associated with G s , rather than the G i/o -associated mechanisms that have classically been ascribed to D2Rs. SIGNIFICANCE STATEMENT Dopamine D2 receptors (D2Rs) in the prefrontal cortex (PFC) are thought to play important roles in behaviors, including working memory and cognitive flexibility. Variation in D2Rs has also been

  11. Peripheral intravenous line - infants (United States)

    PIV - infants; Peripheral IV - infants; Peripheral line - infants; Peripheral line - neonatal ... A peripheral intravenous line (PIV) is a small, short, plastic tube, called a catheter. A health care provider puts the PIV through the ...

  12. Sewer Main Pipe Lines (United States)

    U.S. Environmental Protection Agency — This is a line feature dataset with lines across the island of Guam. These lines represent the sewer mains that carry refuse to the sewer plants for processing and...

  13. UV-dependent production of 25-hydroxyvitamin D2 in the recombinant yeast cells expressing human CYP2R1. (United States)

    Yasuda, Kaori; Endo, Mariko; Ikushiro, Shinichi; Kamakura, Masaki; Ohta, Miho; Sakaki, Toshiyuki


    CYP2R1 is known to be a physiologically important vitamin D 25-hydroxylase. We have successfully expressed human CYP2R1 in Saccharomyces cerevisiae to reveal its enzymatic properties. In this study, we examined production of 25-hydroxylated vitamin D using whole recombinant yeast cells that expressed CYP2R1. When vitamin D3 or vitamin D2 was added to the cell suspension of CYP2R1-expressing yeast cells in a buffer containing glucose and β-cyclodextrin, the vitamins were converted into their 25-hydroxylated products. Next, we irradiated the cell suspension with UVB and incubated at 37 °C. Surprisingly, the 25-hydroxy vitamin D2 was produced without additional vitamin D2. Endogenous ergosterol was likely converted into vitamin D2 by UV irradiation and thermal isomerization, and then the resulting vitamin D2 was converted to 25-hydroxyvitamin D2 by CYP2R1. This novel method for producing 25-hydroxyvitamin D2 without a substrate could be useful for practical purposes. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Genetic dissection of leukemia-associated IDH1 and IDH2 mutants and D-2-hydroxyglutarate in Drosophila (United States)

    Reitman, Zachary J.; Sinenko, Sergey A.; Spana, Eric P.


    Gain-of-function mutations in nicotinamide adenine dinucleotide phosphate–dependent isocitrate dehydrogenase (IDH)1 and IDH2 frequently arise in human leukemias and other cancers and produce high levels of D-2-hydroxyglutarate (D-2HG). We expressed the R195H mutant of Drosophila Idh (CG7176), which is equivalent to the human cancer-associated IDH1-R132H mutant, in fly tissues using the UAS-Gal4 binary expression system. Idh-R195H caused a >25-fold elevation of D-2HG when expressed ubiquitously in flies. Expression of mutant Idh in larval blood cells (hemocytes) resulted in higher numbers of circulating blood cells. Mutant Idh expression in fly neurons resulted in neurologic and wing-expansion defects, and these phenotypes were rescued by genetic modulation of superoxide dismutase 2, p53, and apoptotic caspase cascade mediators. Idh-R163Q, which is homologous to the common leukemia-associated IDH2-R140Q mutant, resulted in moderately elevated D-2HG and milder phenotypes. We identified the fly homolog of D-2-hydroxyglutaric acid dehydrogenase (CG3835), which metabolizes D-2HG, and showed that coexpression of this enzyme with mutant Idh abolishes mutant Idh-associated phenotypes. These results provide a flexible model system to interrogate a cancer-related genetic and metabolic pathway and offer insights into the impact of IDH mutation and D-2HG on metazoan tissues. PMID:25398939

  15. Altered ratio of D1 and D2 dopamine receptors in mouse striatum is associated with behavioral sensitization to cocaine.

    Directory of Open Access Journals (Sweden)

    Dawn Thompson

    Full Text Available BACKGROUND: Drugs of abuse elevate brain dopamine levels, and, in vivo, chronic drug use is accompanied by a selective decrease in dopamine D2 receptor (D2R availability in the brain. Such a decrease consequently alters the ratio of D1R:D2R signaling towards the D1R. Despite a plethora of behavioral studies dedicated to the understanding of the role of dopamine in addiction, a molecular mechanism responsible for the downregulation of the D2R, in vivo, in response to chronic drug use has yet to be identified. METHODS AND FINDINGS: ETHICS STATEMENT: All animal work was approved by the Gallo Center IACUC committee and was performed in our AAALAC approved facility. In this study, we used wild type (WT and G protein coupled receptor associated sorting protein-1 (GASP-1 knock out (KO mice to assess molecular changes that accompany cocaine sensitization. Here, we show that downregulation of D2Rs or upregulation of D1Rs is associated with a sensitized locomotor response to an acute injection of cocaine. Furthermore, we demonstrate that disruption of GASP-1, that targets D2Rs for degradation after endocytosis, prevents cocaine-induced downregulation of D2Rs. As a consequence, mice with a GASP-1 disruption show a reduction in the sensitized locomotor response to cocaine. CONCLUSIONS: Together, our data suggests that changes in the ratio of the D1:D2R could contribute to cocaine-induced behavioral plasticity and demonstrates a role of GASP-1 in regulating both the levels of the D2R and cocaine sensitization.

  16. Suramin blocks interaction between human FGF1 and FGFR2 D2 domain and reduces downstream signaling activity

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zong-Sian, E-mail: [Department of Chemistry, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Liu, Che Fu, E-mail: [Department of Chemistry, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Fu, Brian, E-mail: [Northwood High School, Irvine, CA (United States); Chou, Ruey-Hwang, E-mail: [Graduate Institute of Cancer Biology and Center for Molecular Medicine, China Medical University, No.91, Hsueh-Shih Road, Taichung 40402, Taiwan (China); Department of Biotechnology, Asia University, Taiwan (China); Yu, Chin, E-mail: [Department of Chemistry, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China)


    The extracellular portion of the human fibroblast growth factor receptor2 D2 domain (FGFR2 D2) interacts with human fibroblast growth factor 1 (hFGF1) to activate a downstream signaling cascade that ultimately affects mitosis and differentiation. Suramin is an antiparasiticdrug and a potent inhibitor of FGF-induced angiogenesis. Suramin has been shown to bind to hFGF1, and might block the interaction between hFGF1 and FGFR2 D2. Here, we titrated hFGF1 with FGFR2 D2 and suramin to elucidate their interactions using the detection of NMR. The docking results of both hFGF1-FGFR2 D2 domain and hFGF1-suramin complex were superimposed. The results indicate that suramin blocks the interaction between hFGF1 and FGFR2 D2. We used the PyMOL software to show the hydrophobic interaction of hFGF1-suramin. In addition, we used a Water-soluble Tetrazolium salts assay (WST1) to assess hFGF1 bioactivity. The results will be useful for the development of new antimitogenic activity drugs. - Highlights: • The interfacial residues on hFGF1-FGFR2 D2 and hFGF1-Suramin contact surface were mapped by {sup 1}H-{sup 15}N HSQC experiments. • hFGF1-FGFR2 D2 and hFGF1-Suramin complex models were generated from NMR restraints by using HADDOCK program. • We analyzed hFGF1-Suramin complex models and found the interaction between hFGF1-Suramin is hydrophobic. • The bioactivity of the hFGF1-FGFR2 D2 and hFGF1-Suramin complex was studied by using WST1 assay.

  17. EANM procedure guidelines for brain neurotransmission SPECT/PET using dopamine D2 receptor ligands, version 2

    DEFF Research Database (Denmark)

    Van Laere, Koen; Varrone, Andrea; Booij, Jan


    The guidelines summarize the current views of the European Association of Nuclear Medicine Neuroimaging Committee (ENC). The aims of the guidelines are to assist nuclear medicine practitioners in making recommendations, performing, interpreting and reporting the results of clinical dopamine D2...... receptor SPECT or PET studies, and to achieve a high quality standard of dopamine D2 receptor imaging, which will increase the impact of this technique in neurological practice.The present document is an update of the first guidelines for SPECT using D2 receptor ligands labelled with (123)I [1...

  18. Model-based meta-analysis for comparing Vitamin D2 and D3 parent-metabolite pharmacokinetics. (United States)

    Ocampo-Pelland, Alanna S; Gastonguay, Marc R; Riggs, Matthew M


    Association of Vitamin D (D3 & D2) and its 25OHD metabolite (25OHD3 & 25OHD2) exposures with various diseases is an active research area. D3 and D2 dose-equivalency and each form's ability to raise 25OHD concentrations are not well-defined. The current work describes a population pharmacokinetic (PK) model for D2 and 25OHD2 and the use of a previously developed D3-25OHD3 PK model [1] for comparing D3 and D2-related exposures. Public-source D2 and 25OHD2 PK data in healthy or osteoporotic populations, including 17 studies representing 278 individuals (15 individual-level and 18 arm-level units), were selected using search criteria in PUBMED. Data included oral, single and multiple D2 doses (400-100,000 IU/d). Nonlinear mixed effects models were developed simultaneously for D2 and 25OHD2 PK (NONMEM v7.2) by considering 1- and 2-compartment models with linear or nonlinear clearance. Unit-level random effects and residual errors were weighted by arm sample size. Model simulations compared 25OHD exposures, following repeated D2 and D3 oral administration across typical dosing and baseline ranges. D2 parent and metabolite were each described by 2-compartment models with numerous parameter estimates shared with the D3-25OHD3 model [1]. Notably, parent D2 was eliminated (converted to 25OHD) through a first-order clearance whereas the previously published D3 model [1] included a saturable non-linear clearance. Similar to 25OHD3 PK model results [1], 25OHD2 was eliminated by a first-order clearance, which was almost twice as fast as the former. Simulations at lower baselines, following lower equivalent doses, indicated that D3 was more effective than D2 at raising 25OHD concentrations. Due to saturation of D3 clearance, however, at higher doses or baselines, the probability of D2 surpassing D3's ability to raise 25OHD concentrations increased substantially. Since 25OHD concentrations generally surpassed 75 nmol/L at these higher baselines by 3 months, there would be no

  19. Preliminary Neutronic Study of D2O-cooled High Conversion PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Hikaru Hiruta; Gilles Youinou


    This paper presents a preliminary neutronics analysis of tight-pitch D2O-cooled high-conversion PWRs loaded with MOX fuel aiming at high Pu conversion and negative void coefficient. SCALE6.1 has been exclusively utilized for this study. The analyses are performed in two separate parts. The first part of this paper investigates the performance of axial and internal blankets and seeks break-even or near-breeder core even without the presence of radial blankets. The second part of this paper performs sensitivity and uncertainty analyses of integral parameters (keff and void coefficient) for selected systems in order to analyze the characters of this high-conversion PWR from different aspects.

  20. Salmonella Disrupts Host Endocytic Trafficking by SopD2-Mediated Inhibition of Rab7

    Directory of Open Access Journals (Sweden)

    Vanessa M. D’Costa


    Full Text Available Intracellular bacterial pathogens of a diverse nature share the ability to evade host immunity by impairing trafficking of endocytic cargo to lysosomes for degradation, a process that is poorly understood. Here, we show that the Salmonella enterica type 3 secreted effector SopD2 mediates this process by binding the host regulatory GTPase Rab7 and inhibiting its nucleotide exchange. Consequently, this limits Rab7 interaction with its dynein- and kinesin-binding effectors RILP and FYCO1 and thereby disrupts host-driven regulation of microtubule motors. Our study identifies a bacterial effector capable of directly binding and thereby modulating Rab7 activity and a mechanism of endocytic trafficking disruption that may provide insight into the pathogenesis of other bacteria. Additionally, we provide a powerful tool for the study of Rab7 function, and a potential therapeutic target.

  1. Product lambda-doublet ratios for the O(3P) + D2 reaction: A mechanistic imprint

    CERN Document Server

    Jambrina, P G; Aldegunde, J; Brouard, M; Aoiz, F J


    In the last decade, the development of theoretical methods have allowed chemists to reproduce and explain almost all of the experimental data associated with elementary atom plus diatom collisions. However, there are still a few examples where theory cannot account yet for experimental results. This is the case for the preferential population of one of the $\\Lambda$-doublet states produced by chemical reactions. In particular, recent measurements of the OD($^2\\Pi$) product of the O($^3$P) + D$_2$ reaction have shown a clear preference for the $\\Pi(A')$ $\\Lambda$-doublet states, in apparent contradiction with {\\em ab initio} calculations, which predict a larger reactivity on the $A"$ potential energy surface. Here we present a method to calculate the $\\Lambda$-doublet ratio when concurrent potential energy surfaces participate in the reaction. It accounts for the experimental $\\Lambda$-doublet populations via explicit consideration of the stereodynamics of the process. Furthermore, our results demonstrate that...

  2. Aggregation and Trunking of M2M Traffic via D2D Connections

    DEFF Research Database (Denmark)

    Rigazzi, Giovanni; Kiilerich Pratas, Nuno; Popovski, Petar


    Machine-to-Machine (M2M) communications is one of the key enablers of the Internet of Things (IoT). Billions of devices are expected to be deployed in the near future for novel M2M applications demanding ubiquitous access and global connectivity. In order to cope with the massive number of machines......, there is a need for new techniques to coordinate the access and allocate the resources. Although the majority of the proposed solutions are focused on the adaptation of the traditional cellular networks to the M2M traffic patterns, novel approaches based on the direct communication among nearby devices may...... represent an effective way to avoid access congestion and cell overload. In this paper, we propose a new strategy inspired by the classical Trunked Radio Systems (TRS), exploiting the Device-to-Device (D2D) connectivity between cellular users and Machine-Type Devices (MTDs). The aggregation of the locally...

  3. Vibrational relaxation of the bending mode of HDO in liquid D2O. (United States)

    Bodis, Pavol; Larsen, Olaf F A; Woutersen, Sander


    The vibrational relaxation of the bending mode of HDO in liquid D2O has been studied using time-resolved mid-infrared pump-probe spectroscopy. At short delays, the transient spectrum clearly shows the v = 1 --> 2 induced absorption and v = 1 --> 0 bleaching and stimulated emission, whereas at long delays, the transient spectrum is dominated by the spectral changes caused by the temperature increase in the sample after vibrational relaxation. From the decay of the v = 1 --> 2 induced absorption, we obtain an estimate of 390 +/- 50 fs for the vibrational lifetime, in surprisingly good agreement with recent theoretical predictions. In the v = 0 --> 1 frequency region, the decay of the absorption change involves a second, slower component, which suggests that after vibrational relaxation the system is not yet in thermal equilibrium.

  4. Providing Fast Discovery in D2D Communication with Full Duplex Technology

    DEFF Research Database (Denmark)

    Gatnau, Marta; Berardinelli, Gilberto; Mahmood, Nurul Huda


    is done according to a fixed probability. However, this configuration may be not appropriate to meet the 10 milliseconds control plane latency target defined for the next 5th generation (5G) system. In this work, we propose a distributed radio resource management framework supporting full duplex...... technology to provide D2D fast discovery. Such framework provides an algorithm to estimate the number of neighbor devices and to dynamically decide the transmission probability, for adapting to network changes and meeting the 10 milliseconds target. Finally, a signaling scheme is proposed to reduce...... the network interference. Results show that our framework performs better than a static approach, reducing the time it takes to complete the discovery phase. In addition, supporting full duplex allows to further reduce the discovery time compared to half duplex transmission mode....

  5. Master actions for massive spin-3 particles in D = 2 + 1 (United States)

    Mendonça, Elias Leite; Dalmazi, Denis


    We present here a relationship between massive self-dual models for spin-3 particles in D=2+1 via the master action procedure. Starting with a first-order model (in the derivatives) S_{SD(1)} we have constructed a master action which interpolates between a sequence of four self-dual models S_{SD(i)} where i=1, 2, 3, 4. By analyzing the particle content of the mixing terms, we give additional arguments that explain why it is apparently impossible to jump from the fourth-order model to a higher-order model. We have also analyzed similarities and differences between the fourth-order K-term in the spin-2 case and the analogous fourth-order term in the spin-3 context.

  6. Identification of market trends with string and D2-brane maps (United States)

    Bartoš, Erik; Pinčák, Richard


    The multidimensional string objects are introduced as a new alternative for an application of string models for time series forecasting in trading on financial markets. The objects are represented by open string with 2-endpoints and D2-brane, which are continuous enhancement of 1-endpoint open string model. We show how new object properties can change the statistics of the predictors, which makes them the candidates for modeling a wide range of time series systems. String angular momentum is proposed as another tool to analyze the stability of currency rates except the historical volatility. To show the reliability of our approach with application of string models for time series forecasting we present the results of real demo simulations for four currency exchange pairs.

  7. X3d2pov. Traductor of X3D to POV-Ray

    Directory of Open Access Journals (Sweden)

    Andrea Castellanos Mendoza


    Full Text Available High-quality and low-quality interactive graphics represent two different approaches to computer graphics’ 3D object representation. The former is mainly used to produce high computational cost movie animation. The latter is used for producing interactive scenes as part of virtual reality environments. Many file format specifications have appeared to satisfy underlying model needs; POV-ray (persistence of vision is an open source specification for rendering photorealistic images with the ray tracer algorithm and X3D (extendable 3D as the VRML successor standard for producing web virtual-reality environments written in XML. X3D2POV has been introduced to render high-quality images from an X3D scene specification; it is a grammar translator tool from X3D code to POV-ray code.

  8. Release of prostaglandin D2 by murine mast cells: importance of metabolite formation for antiproliferative activity

    Directory of Open Access Journals (Sweden)

    C. Haberl


    Full Text Available Prostaglandin (PG D2 , PGJ2 and Δ12 -PGJ2 are antiproliferative eicosanoids. We investigated the production of PGD2 by murine bone marrow-derived mast cells (BMMC taking into consideration metabolism of PGD2 to PGD2 and Δ12-PGJ2. PG-metabolites were quantified by high performance liquid chromatography (HPLC combined with radioimmunoassay (RIA. Stimulated with calcium ionophore A23187 BMMC released eight-fold more PGJ2 and Δ12-PGJ2 than PGD2. Conversion of endogenously produced PGD2 to PGJ2 and Δ12-PGJ2 proceeded rapidly in contrast to metabolism of exogenously added PGD2. The antiproliferative potency of these prostaglandins is demonstrated in vitro. We conclude that determination of PGD2 production by mast cells must take into consideration rapid conversion to active derivatives, which may play a significant role in growth regulation.

  9. Power Control for D2D Underlay Cellular Networks with Imperfect CSI

    KAUST Repository

    Memmi, Amen


    Device-to-Device communications underlying the cellular infrastructure is a technology that has recently been proposed as a promising solution to enhance cellular network capabilities. However, interference is the major challenge since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this work, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Differently from previous works, we are assuming that the channel state information may be imperfect and include estimation errors. We evaluate how this uncertainty impacts performances. In the centralized approach, we derive the optimal powers that maximize the coverage probability and the rate of the cellular user while scheduling as many D2D links as possible. These powers are computed at the base station (BS) and then delivered to the users, and hence the name

  10. Dopamine D1/D2 receptors do not mediate the expression of conditioned place preference induced by the aftereffect of wheel running. (United States)

    Trost, Alexandra; Hauber, Wolfgang


    Rats lever-press for access to running wheels suggesting that wheel running by itself is reinforcing. Furthermore, pairings of an episode of wheel running and subsequent confinement in a specific environment can establish a conditioned place preference (CPP). This finding implies that the reinforcing effects of wheel running outlast the actual occurrence of physical activity, a phenomenon referred to as aftereffect of wheel running. Aftereffect-induced CPP involves Pavlovian conditioning, i.e. repeated pairings of the aftereffect of wheel running with a specific environment creates a learned association between aftereffect and environment and, in turn, a preference for that environment. Given the involvement of dopamine systems in mediating effects of Pavlovian stimuli on appetitive behavior, a role of dopamine in mediating aftereffect-induced CPP seems plausible. Here we assessed whether the mixed D1/D2 receptor antagonist flupenthixol (0.25 mg/kg, i.p.) can block the expression of an aftereffect-induced CPP. In line with earlier studies, our results demonstrate that rats displayed a conditioned preference for environments paired with the aftereffect of wheel running and further show that the magnitude of CPP was not related to the wheel running rate. Furthermore, we found that flupenthixol (0.25 mg/kg, i.p.) reduced locomotor activity but did not attenuate the expression of an aftereffect-induced CPP. The expression of a CPP produced by the aftereffect of wheel running seems not to depend on dopamine D1/D2 receptor activation.

  11. Regional CNS densities of serotonin 1A and dopamine D2 receptors in periadolescent alcohol-preferring P and alcohol-nonpreferring NP rat pups. (United States)

    Strother, Wendy N; Lumeng, Larry; Li, Ting-Kai; McBride, William J


    The objective of the present study was to use quantitative autoradiography to determine binding densities of serotonin(1A) (5-HT(1A)) and dopamine (DA) D(2) receptors in alcohol-naive periadolescent P and NP rat pups. P (n=8) and NP (n=7) rat pups, 25 days of age, from different litters were used. Coronal brain sections were incubated with 2 nM [3H]8-OH-DPAT or 20 nM [3H]sulpiride for 5-HT(1A) or D(2) binding, respectively. Approximately 15-40% higher densities of [3H]8-OH-DPAT binding were observed in the anterior cortical regions of the periadolescent P rat compared with NP rat pups. Similar differences were also observed in posterior cortical regions with P rats having 25-40% higher [3H]8-OH-DPAT binding than NP rats. [3H]8-OH-DPAT binding was approximately 10-20% higher in posterior hippocampal regions of the P rat pups compared with the NP line. [3H]sulpiride binding was significantly different only in the ventral tegmental area (VTA), where binding was approximately 20% lower in the periadolescent P rats compared with the NP rat pups. Overall, these results are very similar to findings observed in adult alcohol-naive P and NP rats, and suggest that the innate differences in the neural systems implicated in high alcohol drinking behaviors may already be established in the periadolescent animal.

  12. Weyl and transverse diffeomorphism invariant spin-2 models in D = 2 + 1

    Energy Technology Data Exchange (ETDEWEB)

    Dalmazi, Denis; Mendonca, E.L. [UNESP-Campus de Guaratingueta-DFQ, Guaratingueta, SP (Brazil); ICTP South American Institute for Fundamental Research, IFT-UNESP, Sao Paulo, SP (Brazil); Santos, A.L.R. dos [UNESP-Campus de Guaratingueta-DFQ, Guaratingueta, SP (Brazil); Ghosh, Subir [ICTP South American Institute for Fundamental Research, IFT-UNESP, Sao Paulo, SP (Brazil); Indian Statistical Institute, Physics and Applied Mathematics Unit, Kolkata (India)


    There are two covariant descriptions of massless spin-2 particles in D = 3 + 1 via a symmetric rank-2 tensor: the linearized Einstein-Hilbert (LEH) theory and the Weyl plus transverse diffeomorphism (WTDIFF) invariant model. From the LEH theory one can obtain the linearized new massive gravity (NMG) in D = 2 + 1 via Kaluza-Klein dimensional reduction followed by a dual master action. Here we show that a similar route takes us from the WTDIFF model to a linearized scalar-tensor NMG which belongs to a larger class of consistent spin-0 modifications of NMG. We also show that a traceless master action applied to a parity singlet furnishes two new spin-2 self-dual models. Moreover, we examine the singular replacement h{sub μν} → h{sub μν} - η{sub μν}h/D and prove that it leads to consistent massive spin-2 models in D = 2 + 1. They include linearized versions of unimodular topologically massive gravity (TMG) and unimodular NMG. Although the free part of those unimodular theories are Weyl invariant, we do not expect any improvement in the renormalizability. Both the linearized K-term (in NMG) and the linearized gravitational Chern-Simons term (in TMG) are invariant under longitudinal reparametrizations δh{sub μν} = ∂{sub μ}∂{sub ν}ζ, which is not a symmetry of the WTDIFF Einstein-Hilbert term. Therefore, we still have one degree of freedom whose propagator behaves like 1/p{sup 2} for large momentum. (orig.)

  13. Interaction between LSD and dopamine D2/3 binding sites in pig brain. (United States)

    Minuzzi, Luciano; Nomikos, George G; Wade, Mark R; Jensen, Svend B; Olsen, Aage K; Cumming, Paul


    The psychoactive properties of the hallucinogen LSD have frequently been attributed to high affinity interactions with serotonin 5HT2 receptors in brain. Possible effects of LSD on dopamine D2/3 receptor availability have not previously been investigated in living brain. Therefore, we used PET to map the binding potential (pB) of [11C]raclopride in brain of three pigs, first in a baseline condition, and again at 1 and 4 h after administration of LSD (2.5 microg/kg, i.v.). There was a progressive treatment effect in striatum, where the pB was significantly reduced by 19% at 4 h after LSD administration. Concomitant maps of cerebral blood flow did not reveal significant changes in perfusion during this interval. Subsequent in vitro studies showed that LSD displaced [3H]raclopride (2 nM) from pig brain cryostat sections with an IC50 of 275 nM according to a one-site model. Fitting of a two-site model to the data suggested the presence of a component of the displacement curves with a subnanomolar IC50, comprising 20% of the total [3H]raclopride binding. In microdialysis experiments, LSD at similar and higher doses did not evoke changes in the interstitial concentration of dopamine or its acidic metabolites in rat striatum. Together, these results are consistent with a direct interaction between LSD and a portion of dopamine D2/3 receptors in pig brain, possibly contributing to the psychopharmacology of LSD. (c) 2005 Wiley-Liss, Inc.

  14. RF power transfer efficiency of inductively coupled low pressure H2 and D2 discharges (United States)

    Rauner, D.; Briefi, S.; Fantz, U.


    The RF power transfer efficiency and the relevant power absorption mechanisms of inductively heated hydrogen and deuterium plasmas are investigated in the low-pressure region between 0.25 and 10 Pa. The discharges are generated in a cylindrical vessel via a helical coil applying a frequency of 1 MHz and delivered RF powers up to 800 W. The power transfer efficiency η is quantified by a subtractive method that relies on the measurement of the delivered RF power and of the RF current through the plasma coil both with and without discharge operation. By means of optical emission spectroscopy and electrical probe measurements, the key plasma parameters are obtained. For both H2 and D2, the relative behavior of the power transfer efficiency is well comparable, which increases with increasing delivered RF power and describes a maximum at pressures between 1 and 3 Pa where more than 90 % of the provided power are absorbed by the plasma. The observed relative dependencies of η on the operational parameters are found to be well explained by an analytical approach that considers the power absorption by the plasma via evaluating the RF plasma conductivity based on the measured plasma parameters. At the parameters present, non-collisional stochastic heating of electrons has to be considered for pressures p≤slant 1 {Pa}, while collisional heating dominates at higher pressure. Molecular dissociation is found to have a significant influence on the power transfer efficiency of light molecular discharges. The direct comparison of H2 and D2 identifies the higher atomic density in deuterium to cause a systematically increased power transfer efficiency due to an increased ionization rate in the present electron temperature region.

  15. Statistical Mechanics of Classical Particles with Gravitational Interactions:. Exactly Solvable (for N≤∞) in d=1 and d>2 (United States)

    Kiessling, Michael K.-H.

    This paper is concerned with a curious gap in a string of exactly solvable models, a gap that is suggestively related to a completely integrable nonlinear PDE in d=2 known as Liouville's equation. This PDE emerges in a limit N→∞ from the equilibrium statistical mechanics of classical point particles with gravitational interactions (SMGI) in dimension d=2 which, accordingly, is an exactly solvable continuum model in this limit. Interestingly, in d=1 and all d>2, the SMGI can be, and partly has been, exactly evaluated for all N≤∞. This entitles one to suspect that the SMGI for d=2 is likewise exactly solvable for N>∞, but currently this is an unproven hypothesis. If this conjecture can be answered in the affirmative, spin-offs in various areas associated with Liouville's equation, such as vortex gases, superfluidity, random matrices, and string theory can be expected.

  16. Cannabis use and striatal D2 receptor density in untreated first-episode psychosis: an in vivo SPECT study. (United States)

    Safont, Gemma; Corripio, Iluminada; Escartí, María J; Portella, Maria J; Pérez, Víctor; Ferrer, Marc; Camacho, Valle; Sauras, Rosa B; Alonso, Anna; Grasa, Eva M; Arranz, Belén; San, Luis; Dueñas, Rosa; Carrió, Ignasi; Álvarez, Enric


    The biological basis of the association between cannabis-induced dopamine dysregulation and psychosis remains poorly understood. This (123)I-IBZM SPECT study assessed striatal dopamine D2 receptor (D2R) binding in 37 untreated first-episode psychosis (FEP) subjects, and 18 healthy controls. The aim was to examine if there were differences between FEP subjects with (n=14) and without (n=23) cannabis use in uptake ratios in the D2R. Striatal/Frontal cortex (S/F) uptake ratios were obtained. Healthy controls showed the lowest D2R binding ratios. No differences were found in S/F ratios between users and non-users, suggesting similar dopaminergic mechanisms underlying psychotic symptoms in both groups. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Wireless Device-to-Device (D2D) Links for Machine-to-Machine (M2M) Communication

    DEFF Research Database (Denmark)

    Pratas, Nuno; Popovski, Petar


    Device-to-Device (D2D) communications will play an important role in the fifth generation (5G) cellular networks, by increasing the spatial reuse of spectrum resources and enabling communication links with low latency. D2D is composed of two fundamental building blocks: proximity discovery...... and direct communication between nearby users. Another emerging trend in wireless cellular systems is Machine-to-Machine (M2M) communications, often characterized by fixed, low transmission rates. In this chapter we motivate the synergy between D2D and M2M, and present technologies that enable M2M-via-D2D...... communication to operate as an underlay to the ordinary cellular transmissions....

  18. Analytical modeling of mode selection and power control for underlay D2D communication in cellular networks

    KAUST Repository

    Elsawy, Hesham


    Device-to-device (D2D) communication enables the user equipments (UEs) located in close proximity to bypass the cellular base stations (BSs) and directly connect to each other, and thereby, offload traffic from the cellular infrastructure. D2D communication can improve spatial frequency reuse and energy efficiency in cellular networks. This paper presents a comprehensive and tractable analytical framework for D2D-enabled uplink cellular networks with a flexible mode selection scheme along with truncated channel inversion power control. The developed framework is used to analyze and understand how the underlaying D2D communication affects the cellular network performance. Through comprehensive numerical analysis, we investigate the expected performance gains and provide guidelines for selecting the network parameters.

  19. Biosynthesis of the D2 cell adhesion molecule: pulse-chase studies in cultured fetal rat neuronal cells

    DEFF Research Database (Denmark)

    Lyles, J M; Norrild, B; Bock, E


    D2 is a membrane glycoprotein that is believed to function as a cell adhesion molecule (CAM) in neural cells. We have examined its biosynthesis in cultured fetal rat brain neurones. We found D2-CAM to be synthesized initially as two polypeptides: Mr 186,000 (A) and Mr 136,000 (B). With increasing...... chase times the Mr of both molecules increased to 187,000-201,000 (A) and 137,000-158,000 (B). These were similar to the sizes of D2-CAM labeled with [14C]glucosamine, [3H]fucose and [14C]mannosamine, indicating that the higher Mr species are glycoproteins. In the presence of tunicamycin, which...... pulse or chase times, showing that these molecules are not interconverted. Thus, our data indicate that the neuronal D2-CAM glycoproteins are derived from two mRNAs....

  20. Promoter- and cell-specific epigenetic regulation of CD44, Cyclin D2, GLIPR1 and PTEN by Methyl-CpG binding proteins and histone modifications

    Directory of Open Access Journals (Sweden)

    Schwarzenbach Heidi


    Full Text Available Abstract Background The aim of the current study was to analyze the involvement of methyl-CpG binding proteins (MBDs and histone modifications on the regulation of CD44, Cyclin D2, GLIPR1 and PTEN in different cellular contexts such as the prostate cancer cells DU145 and LNCaP, and the breast cancer cells MCF-7. Since global chromatin changes have been shown to occur in tumours and regions of tumour-associated genes are affected by epigenetic modifications, these may constitute important regulatory mechanisms for the pathogenesis of malignant transformation. Methods In DU145, LNCaP and MCF-7 cells mRNA expression levels of CD44, Cyclin D2, GLIPR1 and PTEN were determined by quantitative RT-PCR at the basal status as well as after treatment with demethylating agent 5-aza-2'-deoxycytidine and/or histone deacetylase inhibitor Trichostatin A. Furthermore, genomic DNA was bisulfite-converted and sequenced. Chromatin immunoprecipitation was performed with the stimulated and unstimulated cells using antibodies for MBD1, MBD2 and MeCP2 as well as 17 different histone antibodies. Results Comparison of the different promoters showed that MeCP2 and MBD2a repressed promoter-specifically Cyclin D2 in all cell lines, whereas in MCF-7 cells MeCP2 repressed cell-specifically all methylated promoters. Chromatin immunoprecipitation showed that all methylated promoters associated with at least one MBD. Treatment of the cells by the demethylating agent 5-aza-2'-deoxycytidine (5-aza-CdR caused dissociation of the MBDs from the promoters. Only MBD1v1 bound and repressed methylation-independently all promoters. Real-time amplification of DNA immunoprecipitated by 17 different antibodies showed a preferential enrichment for methylated lysine of histone H3 (H3K4me1, H3K4me2 and H3K4me3 at the particular promoters. Notably, the silent promoters were associated with unmodified histones which were acetylated following treatment by 5-aza-CdR. Conclusions This study is one

  1. Spatial Working Memory in Male Rats: Pre-Experience and Task Dependent Roles of Dopamine D1- and D2-Like Receptors

    Directory of Open Access Journals (Sweden)

    Mekite Bezu


    Full Text Available The dopaminergic system is known to be involved in working memory processed by several brain regions like prefrontal cortex (PFC, hippocampus, striatum. In an earlier study we could show that Levodopa but not Modafinil enhanced working memory in a T-maze only during the early phase of training (day 3, whereas the later phase remained unaffected. Rats treated with a higher dose performed better than low dose treated rats. Here we could more specifically segregate the contributions of dopamine type 1- and 2- like receptors (D1R; D2R to the training state dependent modulation of spatial working memory by intracerebroventricular (ICV application of a D1R-like (SKF81297 and D2R-like agonist (Sumanirole and antagonist (SCH23390, Remoxipride at a low and high dose through 3 days of training. The D1R-like-agonist at both doses enhanced working memory at day 1 but only in the low dose treated rats enhancement persists over training compared to control rats. Rats treated with a high dose of a D1R-like-antagonist show persistent enhancement of working memory over training, whereas in low dose treated rats no statistical difference at any time point could be determined compared to controls. The D2R-like-agonist at both doses does not show an effect at any time point when compared to control animals, whereas the D2R-like antagonist at a low dose enhanced working memory at day 2. For the most effective D1R-like agonist, we repeated the experiments in a water maze working memory task, to test for task dependent differences in working memory modulations. Treated rats at both doses did not differ as compared to controls, but the temporal behavioral performance of all groups was different compared to T-maze trained rats. The results are in line with the view that spatial working memory is optimized within a limited range of dopaminergic transmission, however suggest that these ranges vary during spatial training.

  2. A Cyclin D2-derived peptide acts on specific cell cycle phases by activating ERK1/2 to cause the death of breast cancer cells. (United States)

    Russo, Lilian C; Araujo, Christiane B; Iwai, Leo K; Ferro, Emer S; Forti, Fabio L


    Protein degradation by the proteasome generates functional intracellular peptides. Pep5, a peptide derived from Cyclin D2, induces cell death in tumor cell lines and reduces the volume of rat C6 glioblastoma tumors in vivo. Here, we chose the human MDA-MB-231 breast cancer cells to evaluate the mechanism of cell death induced by pep5 in different phases of the cell cycle. Fluorescently labeled pep5, monitored by real time confocal microscopy, entered the MDA-MB-231 cells 3min after application and localized to the nucleus and cytoplasm. Pep5-induced cell death was increased when the MDA-MB-231 cell population was arrested at the G1/S transition or in S phase compared to asynchronous cells. Pep5 induced permanent extracellular signal-regulated kinase (ERK1/2) phosphorylation in MDA-MB-231 cells synchronized in G1/S or S phase. Affinity chromatography followed by mass spectrometry identified CLIC1 and Plectin as the only two proteins that interacted with pep5 in both asynchronous and synchronized MDA-MB-231 cells. These interactions could explain the long-lasting ERK1/2 phosphorylation and the cytoskeleton perturbations in the MDA-MB-231 cells, in which the stress fibers' integrity is affected by pep5 treatments. These data suggest that pep5 has potential therapeutic properties for treating specific types of cancers, such as breast cancer cells. Pep5, a natural intracellular peptide formed by the degradation of Cyclin D2 through the ubiquitin-proteasome system, induces cell death when reintroduced into MDA-MB-231 breast cancer cells, which express low levels of Cyclin D2, specifically in G1/S arrested cells or in cells that are passing through S phase. Under these conditions, pep5 is able to interact with different intracellular proteins, primarily cytoskeleton and proteasome components, which can lead to cellular apoptosis. Together, our data suggest that pep5 is an intracellular peptide with therapeutic potential for treating specific types of tumors with low

  3. Control of the 133 cesium cold collisions, search for a variation of the fine structure constant using a dual rubidium-cesium atomic fountain; Controle des collisions froides du cesium {sup 133}Cs: tests de la variation de la constante de structure fine a l'aide d'une fontaine atomique double rubidium-cesium

    Energy Technology Data Exchange (ETDEWEB)

    Marion, H


    We developed a method of measurement of the frequency shift due to the collisions between cold atoms. This is the main systematic limitation for the accuracy of the Cs{sup 133} based fountains ({approx} 10{sup -15} in relative frequency). Consequently, we can measure this effect near 0.5% This opens prospects for improvements of the fountains performances in term of accuracy until 10{sup -16}. The fountain has also obtained a stability about 10{sup -14} at 1 s. We discovered for the first time, at very low magnetic field (5 {+-} 1 mG), Feshbach resonances. We also took a new absolute measurement of the hyperfine transition of the Rb{sup 87}, which is the most precise ever carried out and is used now as definition for the secondary standard. By comparing this value with those measured the previous years, we could carry out a test of the stability of the fine structure constant on the level of 10{sup -15} /yr. We led local comparisons between atomic fountains and the other fountains of the laboratory. Most stable it is unrolled with a combined stability of 5.10{sup -14} at 1 s. The behavior of the difference of the two clocks goes like white frequency noise up to 3.10{sup -16}. The assessment of the dual fountain accuracy budget has been evaluated at 7.10{sup -16} for the cesium part and 8.10{sup -16} for the rubidium part. We contributed to the realization of the scale of International Atomic Time, by series of calibrations of hydrogen masers. An atomic comparison of fountain by satellite links was tested between our laboratory and our German counterpart. This measurement has determined the good agreement between the two clocks. (author)

  4. Malware Memory Analysis for Non-specialists: Investigating Publicly Available Memory Image 0zapftis (R2D2) (United States)


    kernel-based interception technique some rootkits, viruses and Trojan horses use in order to hide themselves from detection. Kthread A Kthread is a...Memory analysis; Memory image; R2D2; Rootkit; Scanners; Trojan horse ; Virus scanner; Volatility; Windows ...investigators can conduct meaningful memory-based investigations on their own. This technical memorandum examines the 0zapftis (R2D2) Trojan horse , in order

  5. Novel aza-analogous ergoline derived scaffolds as potent serotonin 5-HT6 and dopamine D2 receptor ligands

    DEFF Research Database (Denmark)

    Krogsgaard-Larsen, Niels; Jensen, Anders A.; Schrøder, T.J.


    By introducing distal substituents on a tetracyclic scaffold resembling the ergoline structure, two series of analogues were achieved exhibiting subnanomolar receptor binding affinities for the dopamine D2 and serotonin 5-HT6 receptor subtype, respectively. While the 5-HT6 ligands were antagonists......, the D2 ligands displayed intrinsic activities ranging from full agonism to partial agonism with low intrinsic activity. These structures could potentially be interesting for treatment of neurological diseases such as schizophrenia, Parkinson’s disease, and cognitive deficits....

  6. In vivo production of novel vitamin D2 hydroxy-derivatives by human placentas, epidermal keratinocytes, Caco-2 colon cells and the adrenal gland (United States)

    Slominski, Andrzej T.; Kim, Tae-Kang; Shehabi, Haleem Z.; Tang, Edith; Benson, Heather A. E.; Semak, Igor; Lin, Zongtao; Yates, Charles R.; Wang, Jin; Li, Wei; Tuckey, Robert C.


    We investigated the metabolism of vitamin D2 to hydroxyvitamin D2 metabolites ((OH)D2) by human placentas ex-utero, adrenal glands ex-vivo and cultured human epidermal keratinocytes and colonic Caco-2 cells, and identified 20(OH)D2, 17,20(OH)2D2, 1,20(OH)2D2, 25(OH)D2 and 1,25(OH)2D2 as products. Inhibition of product formation by 22R-hydroxycholesterol indicated involvement of CYP11A1 in 20- and 17-hydroxylation of vitamin D2, while use of ketoconazole indicated involvement of CYP27B1 in 1α-hydroxylation of products. Studies with purified human CYP11A1 confirmed the ability of this enzyme to convert vitamin D2 to 20(OH)D2 and 17,20(OH)2D2. In placentas and Caco-2 cells, production of 20(OH)D2 was higher than 25(OH)D2 while in human keratinocytes the production of 20(OH)D2 and 25(OH)D2 were comparable. HaCaT keratinocytes showed high accumulation of 1,20(OH)2D2 relative to 20(OH)D2 indicating substantial CYP27B1 activity. This is the first in vivo evidence for a novel pathway of vitamin D2 metabolism initiated by CYP11A1 and modified by CYP27B1, with the product profile showing tissue- and cell-type specificity. PMID:24382416

  7. Abstract Line Designs (United States)

    Nevinskas, Nancy


    In this article, the author describes a unit on the exploration of line. The unit was composed of two individual line lessons. In the first lesson, students were introduced to line as an element of design. They were asked to describe different types of lines, and look for them in art reproductions. The second lesson in the unit involved painting…

  8. Preliminary Neutronics Design and Analysis of D2O Cooled High Conversion PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Hikaru Hiruta; Gilles Youinou


    This report presents a neutronics analysis of tight-pitch D2O-cooled PWRs loaded with MOX fuel and focuses essentially on the Pu breeding potential of such reactors as well as on an important safety parameter, the void coefficient, which has to be negative. It is well known that fast reactors have a better neutron economy and are better suited than thermal reactors to breed fissile material from neutron capture in fertile material. Such fast reactors (e.g. sodium-cooled reactors) usually rely on technologies that are very different from those of existing water-cooled reactors and are probably more expensive. This report investigates another possibility to obtain a fast neutron reactor while still relying mostly on a PWR technology by: (1) Tightening the lattice pitch to reduce the water-to-fuel volume ratio compared to that of a standard PWR. Water-to-fuel volume ratios of between 0.45 and 1 have been considered in this study while a value of about 2 is typical of standard PWRs, (2) Using D2O instead of H2O as a coolant. Indeed, because of its different neutron physics properties, the use of D2O hardens the neutron spectrum to an extent impossible with H2O when used in a tight-pitch lattice. The neutron spectra thus obtained are not as fast as those in sodium-cooled reactor but they can still be characterized as fast compared to that of standard PWR neutron spectra. In the phase space investigated in this study we did not find any configurations that would have, at the same time, a positive Pu mass balance (more Pu at the end than at the beginning of the irradiation) and a negative void coefficient. At this stage, the use of radial blankets has only been briefly addressed whereas the impact of axial blankets has been well defined. For example, with a D2O-to-fuel volume ratio of 0.45 and a core driver height of about 60 cm, the fissile Pu mass balance between the fresh fuel and the irradiated fuel (50 GWd/t) would be about -7.5% (i.e. there are 7.5% fewer fissile Pu

  9. Challenges in the development of dopamine D2- and D3-selective radiotracers for PET imaging studies. (United States)

    Mach, Robert H; Luedtke, Robert R


    The dopamine D2-like receptors (ie, D2/3 receptors) have been the most extensively studied CNS receptor with Positron Emission Tomography (PET). The 3 different radiotracers that have been used in these studies are [ 11 C]raclopride, [ 18 F]fallypride, and [ 11 C]PHNO. Because these radiotracers have a high affinity for both dopamine D2 and D3 receptors, the density of dopamine receptors in the CNS is reported as the D2/3 binding potential, which reflects a measure of the density of both receptor subtypes. Although the development of D2- and D3-selective PET radiotracers has been an active area of research for many years, this by and large presents an unmet need in the area of translational PET imaging studies. This article discusses some of the challenges that have inhibited progress in this area of research and the current status of the development of subtype selective radiotracers for imaging D3 and D2 dopamine receptors with PET. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Photodesorption of H2O, HDO, and D2O ice and its impact on fractionation (United States)

    Arasa, Carina; Koning, Jesper; Kroes, Geert-Jan; Walsh, Catherine; van Dishoeck, Ewine F.


    The HDO/H2O ratio measured in interstellar gas is often used to draw conclusions on the formation and evolution of water in star-forming regions and, by comparison with cometary data, on the origin of water on Earth. In cold cores and in the outer regions of protoplanetary disks, an important source of gas-phase water comes from photodesorption of water ice. This research note presents fitting formulae for implementation in astrochemical models using previously computed photodesorption efficiencies for all water ice isotopologues obtained with classical molecular dynamics simulations. The results are used to investigate to what extent the gas-phase HDO/H2O ratio reflects that present in the ice or whether fractionation can occur during the photodesorption process. Probabilities for the top four monolayers are presented for photodesorption of X (X = H, D) atoms, OX radicals, and X2O and HDO molecules following photodissociation of H2O, D2O, and HDO in H2O amorphous ice at ice temperatures from 10-100 K. Significant isotope effects are found for all possible products: (1) H atom photodesorption probabilities from H2O ice are larger than those for D atom photodesorption from D2O ice by a factor of 1.1; the ratio of H and D photodesorbed upon HDO photodissociation is a factor of 2. This process will enrich the ice in deuterium atoms over time; (2) the OD/OH photodesorption ratio upon D2O and H2O photodissociation is on average a factor of 2, but the OD/OH photodesorption ratio upon HDO photodissociation is almost constant at unity for all ice temperatures; (3) D atoms are more effective in kicking out neighbouring water molecules than H atoms. However, the ratio of the photodesorbed HDO and H2O molecules is equal to the HDO/H2O ratio in the ice, therefore, there is no isotope fractionation when HDO and H2O photodesorb from the ice. Nevertheless, the enrichment of the ice in D atoms due to photodesorption can over time lead to an enhanced HDO/H2O ratio in the ice, and

  11. PREFACE: International Symposium on Dynamic Deformation and Fracture of Advanced Materials (D2FAM 2013) (United States)

    Silberschmidt, Vadim V.


    Intensification of manufacturing processes and expansion of usability envelopes of modern components and structures in many cases result in dynamic loading regimes that cannot be resented adequately employing quasi-static formulations of respective problems of solid mechanics. Specific features of dynamic deformation, damage and fracture processes are linked to various factors, most important among them being: a transient character of load application; complex scenarios of propagation, attenuation and reflection of stress waves in real materials, components and structures; strain-rate sensitivity of materials properties; various thermo-mechanical regimes. All these factors make both experimental characterisation and theoretical (analytical and numerical) analysis of dynamic deformation and fracture rather challenging; for instance, besides dealing with a spatial realisation of these processes, their evolution with time should be also accounted for. To meet these challenges, an International Symposium on Dynamic Deformation and Fracture of Advanced Materials D2FAM 2013 was held on 9-11 September 2013 in Loughborough, UK. Its aim was to bring together specialists in mechanics of materials, applied mathematics, physics, continuum mechanics, materials science as well as various areas of engineering to discuss advances in experimental and theoretical analysis, and numerical simulations of dynamic mechanical phenomena. Some 50 papers presented at the Symposium by researchers from 12 countries covered various topics including: high-strain-rate loading and deformation; dynamic fracture; impact and blast loading; high-speed penetration; impact fatigue; damping properties of advanced materials; thermomechanics of dynamic loading; stress waves in micro-structured materials; simulation of failure mechanisms and damage accumulation; processes in materials under dynamic loading; a response of components and structures to harsh environment. The materials discussed at D2FAM 2013

  12. Atomic frequency reference at 1033 nm for ytterbium (Yb)-doped fiber lasers and applications exploiting a rubidium (Rb) 5S_1/2 to 4D_5/2 one-colour two-photon transition (United States)

    Roy, Ritayan; Condylis, Paul C.; Johnathan, Yik Jinen; Hessmo, Björn


    We demonstrate a two-photon transition of rubidium (Rb) atoms from the ground state (5$S_{1/2}$) to the excited state (4$D_{5/2}$), using a home-built ytterbium (Yb)-doped fiber amplifier at 1033 nm. This is the first demonstration of an atomic frequency reference at 1033 nm as well as of a one-colour two-photon transition for the above energy levels. A simple optical setup is presented for the two-photon transition fluorescence spectroscopy, which is useful for frequency stabilization for a broad class of lasers. This spectroscopy has potential applications in the fiber laser industry as a frequency reference, particularly for the Yb-doped fiber lasers. This two-photon transition also has applications in atomic physics as a background- free high- resolution atom detection and for quantum communication, which is outlined in this article.

  13. Community LINE Source Model (C-LINE) (United States)

    This presentation provides an introduction for the live demo and explains the purpose of C-LINE and its key features. C-LINE is a web-based model designed to inform the community user of local air quality impacts due to mobile-sources in their region of interest using a simplifie...

  14. Insilico study of the A(2A)R-D (2)R kinetics and interfacial contact surface for heteromerization. (United States)

    Prakash, Amresh; Luthra, Pratibha Mehta


    G-protein-coupled receptors (GPCRs) are cell surface receptors. The dynamic property of receptor-receptor interactions in GPCRs modulates the kinetics of G-protein signaling and stability. In the present work, the structural and dynamic study of A(2A)R-D(2)R interactions was carried to acquire the understanding of the A(2A)R-D(2)R receptor activation and deactivation process, facilitating the design of novel drugs and therapeutic target for Parkinson's disease. The structure-based features (Alpha, Beta, SurfAlpha, and SurfBeta; GapIndex, Leakiness and Gap Volume) and slow mode model (ENM) facilitated the prediction of kinetics (K (off), K (on), and K (d)) of A(2A)R-D(2)R interactions. The results demonstrated the correlation coefficient 0.294 for K (d) and K (on) and the correlation coefficient 0.635 for K (d) and K (off), and indicated stable interfacial contacts in the formation of heterodimer. The coulombic interaction involving the C-terminal tails of the A(2A)R and intracellular loops (ICLs) of D(2)R led to the formation of interfacial contacts between A(2A)R-D(2)R. The properties of structural dynamics, ENM and KFC server-based hot-spot analysis illustrated the stoichiometry of A(2A)R-D(2)R contact interfaces as dimer. The propensity of amino acid residues involved in A(2A)R-D(2)R interaction revealed the presence of positively (R, H and K) and negatively (E and D) charged structural motif of TMs and ICL3 of A(2A)R and D(2)R at interface of dimer contact. Essentially, in silico structural and dynamic study of A(2A)R-D(2)R interactions will provide the basic understanding of the A(2A)R-D(2)R interfacial contact surface for activation and deactivation processes, and could be used as constructive model to recognize the protein-protein interactions in receptor assimilations.

  15. Climatic interpretation of tree-ring methoxyl d2H time-series from a central alpine larch forest (United States)

    Riechelmann, Dana F. C.; Greule, Markus; Siegwolf, Rolf T. W.; Esper, Jan; Keppler, Frank


    We measured stable hydrogen isotope ratios of lignin methoxyl groups (d2HLM) in high elevation larch trees (Larix decidua Mill.) from the Simplon Valley in southern Switzerland. Thirty-seven larch trees were sampled and five individuals analysed for their d2HLM values at annual (1971-2009) and pentadal resolution (1746-2009). Testing the climate response of the d2HLM series, the annually resolved series show a positive correlation of r = 0.60 with June/July precipitation and weaker but negative correlation with June/July temperature. In addition, a negative correlation with June-August d2H in precipitation of the nearby GNIP station in Locarno is observed. The pentadally resolved d2HLM series show no significant correlation to climate parameters. The positive correlation of the annually resolved data to summer precipitation is uncommon to d2H measurements from tree-rings (Feakins et al., 2013; Helle and Schleser, 2004; McCarroll and Loader, 2004; Mischel et al., 2015; White et al., 1994). However, we explain the positive association with warm season hydroclimate as follows: methoxyl groups of lignin are directly formed from tissues in the xylem water. More precipitation during June and July, which are on average relatively dry month, results in higher d2H values of the xylem water and therefore, higher d2H value in the lignin methoxyl groups. Therefore, we suggest that d2HLM values of high elevation larch trees might likely serve as a summer precipitation proxy. References: Feakins, S.J., Ellsworth, P.V., Sternberg, L.d.S.L., 2013. Lignin methoxyl hydrogen isotope rations in a coastal ecosystem. Geochimica et Cosmochimica Acta, 121: 54-66. Helle, G., Schleser, G.H., 2004. Interpreting Climate Proxies from Tree-rings. In: Fischer, H., Floeser, G., Kumke, T., Lohmann, G., Miller, H., Negendank, J.F.W., et al., editors. The Climate in Historical Times. Springer Berlin Heidelberg, pp. 129-148. McCarroll, D., Loader, N.J., 2004. Stable isotopes in tree rings. Quaternary

  16. Epileptogenesis following Kainic Acid-Induced Status Epilepticus in Cyclin D2 Knock-Out Mice with Diminished Adult Neurogenesis.

    Directory of Open Access Journals (Sweden)

    Ilona Kondratiuk

    Full Text Available The goal of this study was to determine whether a substantial decrease in adult neurogenesis influences epileptogenesis evoked by the intra-amygdala injection of kainic acid (KA. Cyclin D2 knockout (cD2 KO mice, which lack adult neurogenesis almost entirely, were used as a model. First, we examined whether status epilepticus (SE evoked by an intra-amygdala injection of KA induces cell proliferation in cD2 KO mice. On the day after SE, we injected BrdU into mice for 5 days and evaluated the number of DCX- and DCX/BrdU-immunopositive cells 3 days later. In cD2 KO control animals, only a small number of DCX+ cells was observed. The number of DCX+ and DCX/BrdU+ cells/mm of subgranular layer in cD2 KO mice increased significantly following SE (p<0.05. However, the number of newly born cells was very low and was significantly lower than in KA-treated wild type (wt mice. To evaluate the impact of diminished neurogenesis on epileptogenesis and early epilepsy, we performed video-EEG monitoring of wt and cD2 KO mice for 16 days following SE. The number of animals with seizures did not differ between wt (11 out of 15 and cD2 KO (9 out of 12 mice. The median latency to the first spontaneous seizure was 4 days (range 2-10 days in wt mice and 8 days (range 2-16 days in cD2 KO mice and did not differ significantly between groups. Similarly, no differences were observed in median seizure frequency (wt: 1.23, range 0.1-3.4; cD2 KO: 0.57, range 0.1-2.0 seizures/day or median seizure duration (wt: 51 s, range 23-103; cD2 KO: 51 s, range 23-103. Our results indicate that SE-induced epileptogenesis is not disrupted in mice with markedly reduced adult neurogenesis. However, we cannot exclude the contribution of reduced neurogenesis to the chronic epileptic state.

  17. [Anti-cholinesterase activity of dopamine D2 receptor antagonist: its clinical significance]. (United States)

    Mizumoto, A; Itoh, Z


    Anti-cholinesterase activity of dopamine D2 receptor antagonist, domperidone was studied by means of chronically implanted force transducers in the gastrointestinal (GI) tract in five conscious dogs. Cisapride was used as a drug to stimulate endogenous release of acetylcholine. In the digestive state, cisapride (0.25 mg/kg) stimulated 18.6 +/- 5.6% increase in the motor index of the gastric antrum alone, however, combined administration with domperidone (1.0 mg/kg-hr) significantly enhanced the motor index in the gastric antrum and duodenum. In the gastric antrum, the increase was 68.1 +/- 7.2%. During the interdigestive state, cisapride did not always induce the interdigestive migrating contractions (IMC)-like contractions in the GI tract, but the background infusion of domperidone significantly increased the incidence of the occurrence of IMC-like contractions by cisapride. In in vitro study, weak but significant anti-cholinesterase activity was found in domperidone, the activity being about 1/1,000 of that of neostigmine. In dog experiment, similar enhancement of motor stimulating activity of cisapride was observed when neostigmine was given at 1.0 micrograms/kg-hr. In conclusion, domperidone has anti-cholinesterase activity and acts to enhance motor stimulating activity of cisapride through inhibition of cholinesterase activity in the upper digestive tract.

  18. Cooperative HARQ Assisted NOMA Scheme in Large-scale D2D Networks

    KAUST Repository

    Shi, Zheng


    This paper develops an interference aware design for cooperative hybrid automatic repeat request (HARQ) assisted non-orthogonal multiple access (NOMA) scheme for large-scale device-to-device (D2D) networks. Specifically, interference aware rate selection and power allocation are considered to maximize long term average throughput (LTAT) and area spectral efficiency (ASE). The design framework is based on stochastic geometry that jointly accounts for the spatial interference correlation at the NOMA receivers as well as the temporal interference correlation across HARQ transmission