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Search Results: 1 - 10 of 87760 matches for " I. Bekman "
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Generation and Characterization of a Novel Mouse Embryonic Stem Cell Line with a Dynamic Reporter of Nanog Expression
Elsa Abranches, Evguenia Bekman, Domingos Henrique
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0059928
Abstract: Background The pluripotent state in embryonic stem (ES) cells is controlled by a core network of transcription factors that includes Nanog, Oct4 and Sox2. Nanog is required to reach pluripotency during somatic reprogramming and is the only core factor whose overexpression is able to oppose differentiation-promoting signals. Additionally, Nanog expression is known to fluctuate in ES cells, and different levels of Nanog seem to correlate with ES cells’ ability to respond to differentiation promoting signals. Elucidating how dynamic Nanog levels are regulated in pluripotent cells and modulate their potential is therefore critical to develop a better understanding of the pluripotent state. Methodology/Principal Findings We describe the generation and validation of a mouse ES cell line with a novel Nanog reporter (Nd, from Nanog dynamics), containing a BAC transgene where the short-lived fluorescent protein VNP is placed under Nanog regulation. We show that Nanog and VNP have similar half-lives, and that Nd cells provide an accurate and measurable read-out for the dynamic levels of Nanog. Using this reporter, we could show that ES cells with low Nanog levels indeed have higher degree of priming to differentiation, when compared with high-Nanog cells. However, low-Nanog ES cells maintain high levels of Oct4 and Sox2 and can revert to a state of high-Nanog expression, indicating that they are still within the window of pluripotency. We further show that the observed changes in Nanog levels correlate with ES cell morphology and that Nanog dynamic expression is modulated by the cellular environment. Conclusions/Significance The novel reporter ES cell line here described allows an accurate monitoring of Nanog’s dynamic expression in the pluripotent state. This reporter will thus be a valuable tool to obtain quantitative measurements of global gene expression in pluripotent ES cells in different states, allowing a detailed molecular mapping of the pluripotency landscape.
Neural Differentiation of Embryonic Stem Cells In Vitro: A Road Map to Neurogenesis in the Embryo
Elsa Abranches, Margarida Silva, Laurent Pradier, Herbert Schulz, Oliver Hummel, Domingos Henrique, Evguenia Bekman
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0006286
Abstract: Background The in vitro generation of neurons from embryonic stem (ES) cells is a promising approach to produce cells suitable for neural tissue repair and cell-based replacement therapies of the nervous system. Available methods to promote ES cell differentiation towards neural lineages attempt to replicate, in different ways, the multistep process of embryonic neural development. However, to achieve this aim in an efficient and reproducible way, a better knowledge of the cellular and molecular events that are involved in the process, from the initial specification of neuroepithelial progenitors to their terminal differentiation into neurons and glial cells, is required. Methodology/Principal Findings In this work, we characterize the main stages and transitions that occur when ES cells are driven into a neural fate, using an adherent monolayer culture system. We established improved conditions to routinely produce highly homogeneous cultures of neuroepithelial progenitors, which organize into neural tube-like rosettes when they acquire competence for neuronal production. Within rosettes, neuroepithelial progenitors display morphological and functional characteristics of their embryonic counterparts, namely, apico-basal polarity, active Notch signalling, and proper timing of production of neurons and glia. In order to characterize the global gene activity correlated with each particular stage of neural development, the full transcriptome of different cell populations that arise during the in vitro differentiation protocol was determined by microarray analysis. By using embryo-oriented criteria to cluster the differentially expressed genes, we define five gene expression signatures that correlate with successive stages in the path from ES cells to neurons. These include a gene signature for a primitive ectoderm-like stage that appears after ES cells enter differentiation, and three gene signatures for subsequent stages of neural progenitor development, from an early stage that follows neural induction to a final stage preceding terminal differentiation. Conclusions/Significance Overall, our work confirms and extends the cellular and molecular parallels between monolayer ES cell neural differentiation and embryonic neural development, revealing in addition novel aspects of the genetic network underlying the multistep process that leads from uncommitted cells to differentiated neurons.
Precision Muon Reconstruction in Double Chooz
Double Chooz collaboration,Y. Abe,J. C. dos Anjos,J. C. Barriere,E. Baussan,I. Bekman,M. Bergevin,T. J. C. Bezerra,L. Bezrukov,E. Blucher,C. Buck,J. Busenitz,A. Cabrera,E. Caden,L. Camilleri,R. Carr,M. Cerrada,P. -J. Chang,E. Chauveau,P. Chimenti,A. P. Collin,E. Conover,J. M. Conrad,J. I. Crespo-Anadón,K. Crum,A. Cucoanes,E. Damon,J. V. Dawson,D. Dietrich,Z. Djurcic,M. Dracos,M. Elnimr,A. Etenko,M. Fallot,F. von Feilitzsch,J. Felde,S. M. Fernandes,V. Fischer,D. Franco,M. Franke,H. Furuta,I. Gil-Botella,L. Giot,M. G?ger-Neff,L. F. G. Gonzalez,L. Goodenough,M. C. Goodman,C. Grant,N. Haag,T. Hara,J. Haser,M. Hofmann,G. A. Horton-Smith,A. Hourlier,M. Ishitsuka,J. Jochum,C. Jollet,F. Kaether,L. N. Kalousis,Y. Kamyshkov,D. M. Kaplan,T. Kawasaki,E. Kemp,H. de Kerret,D. Kryn,M. Kuze,T. Lachenmaier,C. E. Lane,T. Lasserre,A. Letourneau,D. Lhuillier,H. P. Lima Jr,M. Lindner,J. M. López-Casta no,J. M. LoSecco,B. Lubsandorzhiev,S. Lucht,J. Maeda,C. Mariani,J. Maricic,J. Martino,T. Matsubara,G. Mention,A. Meregaglia,T. Miletic,R. Milincic,A. Minotti,Y. Nagasaka,Y. Nikitenko,P. Novella,M. Obolensky,L. Oberauer,A. Onillon,A. Osborn,C. Palomares,I. M. Pepe,S. Perasso,P. Pfahler,A. Porta,G. Pronost,J. Reichenbacher,B. Reinhold,M. R?hling,R. Roncin,S. Roth,B. Rybolt,Y. Sakamoto,R. Santorelli,A. C. Schilithz,S. Sch?nert,S. Schoppmann,M. H. Shaevitz,R. Sharankova,S. Shimojima,V. Sibille,V. Sinev,M. Skorokhvatov,E. Smith,J. Spitz,A. Stahl,I. Stancu,L. F. F. Stokes,M. Strait,A. Stüken,F. Suekane
Physics , 2014, DOI: 10.1016/j.nima.2014.07.058
Abstract: We describe a muon track reconstruction algorithm for the reactor anti-neutrino experiment Double Chooz. The Double Chooz detector consists of two optically isolated volumes of liquid scintillator viewed by PMTs, and an Outer Veto above these made of crossed scintillator strips. Muons are reconstructed by their Outer Veto hit positions along with timing information from the other two detector volumes. All muons are fit under the hypothesis that they are through-going and ultrarelativistic. If the energy depositions suggest that the muon may have stopped, the reconstruction fits also for this hypothesis and chooses between the two via the relative goodness-of-fit. In the ideal case of a through-going muon intersecting the center of the detector, the resolution is ~40 mm in each transverse dimension. High quality muon reconstruction is an important tool for reducing the impact of the cosmogenic isotope background in Double Chooz.
Muon capture on light isotopes in Double Chooz
Double Chooz collaboration,Y. Abe,T. Abrah?o,H. Almazan,C. Alt,S. Appel,J. C. Barriere,E. Baussan,I. Bekman,M. Bergevin,T. J. C. Bezerra,L. Bezrukov,E. Blucher,T. Brugière,C. Buck,J. Busenitz,A. Cabrera,L. Camilleri,R. Carr,M. Cerrada,E. Chauveau,P. Chimenti,A. P. Collin,E. Conover,J. M. Conrad,J. I. Crespo-Anadón,K. Crum,A. S. Cucoanes,E. Damon,J. V. Dawson,H. de Kerret,J. Dhooghe,D. Dietrich,Z. Djurcic,J. C. dos Anjos,M. Dracos,A. Etenko,M. Fallot,J. Felde,S. M. Fernandes,V. Fischer,D. Franco,M. Franke,H. Furuta,I. Gil-Botella,L. Giot,M. G?ger-Neff,H. Gomez,L. F. G. Gonzalez,L. Goodenough,M. C. Goodman,N. Haag,T. Hara,J. Haser,D. Hellwig,M. Hofmann,G. A. Horton-Smith,A. Hourlier,M. Ishitsuka,J. Jochum,C. Jollet,F. Kaether,L. N. Kalousis,Y. Kamyshkov,M. Kaneda,D. M. Kaplan,T. Kawasaki,E. Kemp,D. Kryn,M. Kuze,T. Lachenmaier,C. E. Lane,T. Lasserre,A. Letourneau,D. Lhuillier,H. P. Lima Jr,M. Lindner,J. M. López-Casta?o,J. M. LoSecco,B. Lubsandorzhiev,S. Lucht,J. Maeda,C. Mariani,J. Maricic,J. Martino,T. Matsubara,G. Mention,A. Meregaglia,T. Miletic,R. Milincic,A. Minotti,Y. Nagasaka,D. Navas-Nicolás,P. Novella,L. Oberauer,M. Obolensky,A. Onillon,A. Osborn,C. Palomares,I. M. Pepe,S. Perasso,A. Porta,G. Pronost,J. Reichenbacher,B. Reinhold,M. R?hling,R. Roncin,B. Rybolt,Y. Sakamoto,R. Santorelli,A. C. Schilithz,S. Sch?nert,S. Schoppmann,M. H. Shaevitz,R. Sharankova,D. Shrestha,V. Sibille,V. Sinev,M. Skorokhvatov,E. Smith,M. Soiron,J. Spitz,A. Stahl,I. Stancu,L. F. F. Stokes
Physics , 2015,
Abstract: Using the Double Chooz detector, designed to measure the neutrino mixing angle $\theta_{13}$, the products of $\mu^-$ capture on $^{12}$C, $^{13}$C, $^{14}$N and $^{16}$O have been measured. Over a period of 489.5 days, $2.3\times10^6$ stopping cosmic $\mu^-$ have been collected, of which $1.8\times10^5$ captured on carbon, nitrogen, or oxygen nuclei in the inner detector scintillator or acrylic vessels. The resulting isotopes were tagged using prompt neutron emission (when applicable), the subsequent beta decays, and, in some cases, $\beta$-delayed neutrons. The most precise measurement of the rate of $^{12}\mathrm C(\mu^-,\nu)^{12}\mathrm B$ to date is reported: $6.57^{+0.11}_{-0.21}\times10^{3}\,\mathrm s^{-1}$, or $(17.35^{+0.35}_{-0.59})\%$ of nuclear captures. By tagging excited states emitting gammas, the ground state transition rate to $^{12}$B has been determined to be $5.68^{+0.14}_{-0.23}\times10^3\,\mathrm s^{-1}$. The heretofore unobserved reactions $^{12}\mathrm C(\mu^-,\nu\alpha)^{8}\mathrm{Li}$, $^{13}\mathrm C(\mu^-,\nu\mathrm n\alpha)^{8}\mathrm{Li}$, and $^{13}\mathrm C(\mu^-,\nu\mathrm n)^{12}\mathrm B$ are measured. Further, a population of $\beta$n decays following stopping muons is identified with $5.5\sigma$ significance. Statistics limit our ability to identify these decays definitively. Assuming negligible production of $^{8}$He, the reaction $^{13}\mathrm C(\mu^-,\nu\alpha)^{9}\mathrm{Li}$ is found to be present at the $2.7\sigma$ level. Limits are set on a variety of other processes.
Improved measurements of the neutrino mixing angle $θ_{13}$ with the Double Chooz detector
Y. Abe,J. C. dos Anjos,J. C. Barriere,E. Baussan,I. Bekman,M. Bergevin,T. J. C. Bezerra,L. Bezrukov,E. Blucher,C. Buck,J. Busenitz,A. Cabrera,E. Caden,L. Camilleri,R. Carr,M. Cerrada,P. -J. Chang,E. Chauveau,P. Chimenti,A. P. Collin,E. Conover,J. M. Conrad,J. I. Crespo-Anadón,K. Crum,A. S. Cucoanes,E. Damon,J. V. Dawson,J. Dhooghe,D. Dietrich,Z. Djurcic,M. Dracos,M. Elnimr,A. Etenko,M. Fallot,F. von Feilitzsch,J. Felde,S. M. Fernandes,V. Fischer,D. Franco,M. Franke,H. Furuta,I. Gil-Botella,L. Giot,M. G?ger-Neff,L. F. G. Gonzalez,L. Goodenough,M. C. Goodman,C. Grant,N. Haag,T. Hara,J. Haser,M. Hofmann,G. A. Horton-Smith,A. Hourlier,M. Ishitsuka,J. Jochum,C. Jollet,F. Kaether,L. N. Kalousis,Y. Kamyshkov,D. M. Kaplan,T. Kawasaki,E. Kemp,H. de Kerret,D. Kryn,M. Kuze,T. Lachenmaier,C. E. Lane,T. Lasserre,A. Letourneau,D. Lhuillier,H. P. Lima Jr,M. Lindner,J. M. López-Casta?o,J. M. LoSecco,B. Lubsandorzhiev,S. Lucht,J. Maeda,C. Mariani,J. Maricic,J. Martino,T. Matsubara,G. Mention,A. Meregaglia,T. Miletic,R. Milincic,A. Minotti,Y. Nagasaka,Y. Nikitenko,P. Novella,L. Oberauer,M. Obolensky,A. Onillon,A. Osborn,C. Palomares,I. M. Pepe,S. Perasso,P. Pfahler,A. Porta,G. Pronost,J. Reichenbacher,B. Reinhold,M. R?hling,R. Roncin,S. Roth,B. Rybolt,Y. Sakamoto,R. Santorelli,A. C. Schilithz,S. Sch?nert,S. Schoppmann,M. H. Shaevitz,R. Sharankova,S. Shimojima,D. Shrestha,V. Sibille,V. Sinev,M. Skorokhvatov,E. Smith,J. Spitz,A. Stahl,I. Stancu,L. F. F. Stokes,M. Strait,A. Stüken,F. Suekane
Physics , 2014, DOI: 10.1007/JHEP10(2014)086
Abstract: The Double Chooz experiment presents improved measurements of the neutrino mixing angle $\theta_{13}$ using the data collected in 467.90 live days from a detector positioned at an average distance of 1050 m from two reactor cores at the Chooz nuclear power plant. Several novel techniques have been developed to achieve significant reductions of the backgrounds and systematic uncertainties with respect to previous publications, whereas the efficiency of the $\bar\nu_{e}$ signal has increased. The value of $\theta_{13}$ is measured to be $\sin^{2}2\theta_{13} = 0.090 ^{+0.032}_{-0.029}$ from a fit to the observed energy spectrum. Deviations from the reactor $\bar\nu_{e}$ prediction observed above a prompt signal energy of 4 MeV and possible explanations are also reported. A consistent value of $\theta_{13}$ is obtained from a fit to the observed rate as a function of the reactor power independently of the spectrum shape and background estimation, demonstrating the robustness of the $\theta_{13}$ measurement despite the observed distortion.
Measurement of $θ_{13}$ in Double Chooz using neutron captures on hydrogen with novel background rejection techniques
Double Chooz Collaboration,Y. Abe,T. Abrah?o,H. Almazan,C. Alt,J. C. dos Anjos,J. C. Barriere,E. Baussan,I. Bekman,M. Bergevin,T. J. C. Bezerra,L. Bezrukov,E. Blucher,T. Brugière,C. Buck,J. Busenitz,A. Cabrera,L. Camilleri,R. Carr,M. Cerrada,E. Chauveau,P. Chimenti,A. P. Collin,J. M. Conrad,J. I. Crespo-Anadón,K. Crum,A. S. Cucoanes,E. Damon,J. V. Dawson,J. Dhooghe,D. Dietrich,Z. Djurcic,M. Dracos,A. Etenko,M. Fallot,F. von Feilitzsch,J. Felde,S. M. Fernandes,V. Fischer,D. Franco,M. Franke,H. Furuta,I. Gil-Botella,L. Giot,M. G?ger-Neff,H. Gomez,L. F. G. Gonzalez,L. Goodenough,M. C. Goodman,N. Haag,T. Hara,J. Haser,D. Hellwig,M. Hofmann,G. A. Horton-Smith,A. Hourlier,M. Ishitsuka,J. Jochum,C. Jollet,F. Kaether,L. N. Kalousis,Y. Kamyshkov,M. Kaneda,D. M. Kaplan,T. Kawasaki,E. Kemp,H. de Kerret,D. Kryn,M. Kuze,T. Lachenmaier,C. E. Lane,T. Lasserre,A. Letourneau,D. Lhuillier,H. P. Lima Jr,M. Lindner,J. M. López-Casta?o,J. M. LoSecco,B. Lubsandorzhiev,S. Lucht,J. Maeda,C. Mariani,J. Maricic,J. Martino,T. Matsubara,G. Mention,A. Meregaglia,T. Miletic,R. Milincic,A. Minotti,Y. Nagasaka,D. Navas-Nicolás,P. Novella,L. Oberauer,M. Obolensky,A. Onillon,A. Osborn,C. Palomares,I. M. Pepe,S. Perasso,A. Porta,G. Pronost,J. Reichenbacher,B. Reinhold,M. R?hling,R. Roncin,B. Rybolt,Y. Sakamoto,R. Santorelli,A. C. Schilithz,S. Sch?nert,S. Schoppmann,M. H. Shaevitz,R. Sharankova,D. Shrestha,V. Sibille,V. Sinev,M. Skorokhvatov,E. Smith,M. Soiron,J. Spitz,A. Stahl,I. Stancu,L. F. F. Stokes
Physics , 2015,
Abstract: The Double Chooz collaboration presents a measurement of the neutrino mixing angle $\theta_{13}$ using reactor $\overline{\nu}_{e}$ observed via the inverse beta decay reaction in which the neutron is captured on hydrogen. This measurement is based on 462.72 live days data, approximately twice as much data as in the previous such analysis, collected with a detector positioned at an average distance of 1050m from two reactor cores. Several novel techniques have been developed to achieve significant reductions of the backgrounds and systematic uncertainties. Accidental coincidences, the dominant background in this analysis, are suppressed by more than an order of magnitude with respect to our previous publication by a multi-variate analysis. These improvements demonstrate the capability of precise measurement of reactor $\overline{\nu}_{e}$ without gadolinium loading. Spectral distortions from the $\overline{\nu}_{e}$ reactor flux predictions previously reported with the neutron capture on gadolinium events are confirmed in the independent data sample presented here. A value of $\sin^{2}2\theta_{13} = 0.095^{+0.038}_{-0.039}$(stat+syst) is obtained from a fit to the observed event rate as a function of the reactor power, a method insensitive to the energy spectrum shape. A simultaneous fit of the hydrogen capture events and of the gadolinium capture events yields a measurement of $\sin^{2}2\theta_{13} = 0.088\pm0.033$(stat+syst).
Background-independent measurement of $θ_{13}$ in Double Chooz
Y. Abe,J. C. dos Anjos,J. C. Barriere,E. Baussan,I. Bekman,M. Bergevin,T. J. C. Bezerra,L. Bezrukov,E. Blucher,C. Buck,J. Busenitz,A. Cabrera,E. Caden,L. Camilleri,R. Carr,M. Cerrada,P. -J. Chang,E. Chauveau,P. Chimenti,A. P. Collin,E. Conover,J. M. Conrad,J. I. Crespo-Anadón,K. Crum,A. Cucoanes,E. Damon,J. V. Dawson,D. Dietrich,Z. Djurcic,M. Dracos,M. Elnimr,A. Etenko,M. Fallot,F. von Feilitzsch,J. Felde,S. M. Fernandes,V. Fischer,D. Franco,M. Franke,H. Furuta,I. Gil-Botella,L. Giot,M. G?ger-Neff,L. F. G. Gonzalez,L. Goodenough,M. C. Goodman,C. Grant,N. Haag,T. Hara,J. Haser,M. Hofmann,G. A. Horton-Smith,A. Hourlier,M. Ishitsuka,J. Jochum,C. Jollet,F. Kaether,L. N. Kalousis,Y. Kamyshkov,D. M. Kaplan,T. Kawasaki,E. Kemp,H. de Kerret,T. Konno,D. Kryn,M. Kuze,T. Lachenmaier,C. E. Lane,T. Lasserre,A. Letourneau,D. Lhuillier,H. P. Lima Jr,M. Lindner,J. M. López-Casta?o,J. M. LoSecco,B. K. Lubsandorzhiev,S. Lucht,J. Maeda,C. Mariani,J. Maricic,J. Martino,T. Matsubara,G. Mention,A. Meregaglia,T. Miletic,R. Milincic,A. Minotti,Y. Nagasaka,K. Nakajima,Y. Nikitenko,P. Novella,M. Obolensky,L. Oberauer,A. Onillon,A. Osborn,C. Palomares,I. M. Pepe,S. Perasso,P. Pfahler,A. Porta,G. Pronost,J. Reichenbacher,B. Reinhold,M. R?hling,R. Roncin,S. Roth,B. Rybolt,Y. Sakamoto,R. Santorelli,F. Sato,A. C. Schilithz,S. Sch?nert,S. Schoppmann,M. H. Shaevitz,R. Sharankova,S. Shimojima,V. Sibille,V. Sinev,M. Skorokhvatov,E. Smith,J. Spitz,A. Stahl,I. Stancu,L. F. F. Stokes,M. Strait,A. Stüken
Statistics , 2014, DOI: 10.1016/j.physletb.2014.04.045
Abstract: The oscillation results published by the Double Chooz collaboration in 2011 and 2012 rely on background models substantiated by reactor-on data. In this analysis, we present a background-model-independent measurement of the mixing angle $\theta_{13}$ by including 7.53 days of reactor-off data. A global fit of the observed neutrino rates for different reactor power conditions is performed, yielding a measurement of both $\theta_{13}$ and the total background rate. The results on the mixing angle are improved significantly by including the reactor-off data in the fit, as it provides a direct measurement of the total background rate. This reactor rate modulation analysis considers antineutrino candidates with neutron captures on both Gd and H, whose combination yields $\sin^2(2\theta_{13})=$ 0.102 $\pm$ 0.028(stat.) $\pm$ 0.033(syst.). The results presented in this study are fully consistent with the ones already published by Double Chooz, achieving a competitive precision. They provide, for the first time, a determination of $\theta_{13}$ that does not depend on a background model.
Ortho-positronium observation in the Double Chooz Experiment
Y. Abe,J. C. dos Anjos,J. C. Barriere,E. Baussan,I. Bekman,M. Bergevin,T. J. C. Bezerra,L. Bezrukov,E. Blucher,C. Buck,J. Busenitz,A. Cabrera,E. Caden,L. Camilleri,R. Carr,M. Cerrada,P. -J. Chang,E. Chauveau,P. Chimenti,A. P. Collin,E. Conover,J. M. Conrad,J. I. Crespo-Anadon,K. Crum,A. S. Cucoanes,E. Damon,J. V. Dawson,J. Dhooghe,D. Dietrich,Z. Djurcic,M. Dracos,M. Elnimr,A. Etenko,M. Fallot,F. von Feilitzsch,J. Felde,S. M. Fernandes,V. Fischer,D. Franco,M. Franke,H. Furuta,I. Gil-Botella,L. Giot,M. Goger-Neff,L. F. G. Gonzalez,L. Goodenough,M. C. Goodman,C. Grant,N. Haag,T. Hara,J. Haser,M. Hofmann,G. A. Horton-Smith,A. Hourlier,M. Ishitsuka,J. Jochum,C. Jollet,F. Kaether,L. N. Kalousis,Y. Kamyshkov,D. M. Kaplan,T. Kawasaki,E. Kemp,H. de Kerret,D. Kryn,M. Kuze,T. Lachenmaier,C. E. Lane,T. Lasserre,A. Letourneau,D. Lhuillier,H. P. Lima Jr,M. Lindner,J. M. Lopez-Castano,J. M. LoSecco,B. Lubsandorzhiev,S. Lucht,J. Maeda,C. Mariani,J. Maricic,J. Martino,T. Matsubara,G. Mention,A. Meregaglia,T. Miletic,R. Milincic,A. Minotti,Y. Nagasaka,Y. Nikitenko,P. Novella,L. Oberauer,M. Obolensky,A. Onillon,A. Osborn,C. Palomares,I. M. Pepe,S. Perasso,P. Pfahler,A. Porta,G. Pronost,J. Reichenbacher,B. Reinhold,M. Rohling,R. Roncin,S. Roth,B. Rybolt,Y. Sakamoto,R. Santorelli,A. C. Schilithz,S. Schonert,S. Schoppmann,M. H. Shaevitz,R. Sharankova,S. Shimojima,D. Shrestha,V. Sibille,V. Sinev,M. Skorokhvatov,E. Smith,J. Spitz,A. Stahl,I. Stancu,L. F. F. Stokes,M. Strait,A. Stuken,F. Suekane
Statistics , 2014, DOI: 10.1007/JHEP10(2014)032
Abstract: The Double Chooz experiment measures the neutrino mixing angle $\theta_{13}$ by detecting reactor $\bar{\nu}_e$ via inverse beta decay. The positron-neutron space and time coincidence allows for a sizable background rejection, nonetheless liquid scintillator detectors would profit from a positron/electron discrimination, if feasible in large detector, to suppress the remaining background. Standard particle identification, based on particle dependent time profile of photon emission in liquid scintillator, can not be used given the identical mass of the two particles. However, the positron annihilation is sometimes delayed by the ortho-positronium (o-Ps) metastable state formation, which induces a pulse shape distortion that could be used for positron identification. In this paper we report on the first observation of positronium formation in a large liquid scintillator detector based on pulse shape analysis of single events. The o-Ps formation fraction and its lifetime were measured, finding the values of 44$\%$ $\pm$ 12$\%$ (sys.) $\pm$ 5$\%$ (stat.) and $3.68$ns $\pm$ 0.17ns (sys.) $\pm$ 0.15ns (stat.) respectively, in agreement with the results obtained with a dedicated positron annihilation lifetime spectroscopy setup.
"FAILURE" OF THE GLOBAL MARKET ПРОВАЛ ГЛОБАЛЬНОГО РЫНКА ПРОВАЛИ ГЛОБАЛЬНОГО РИНКУ
Т.В. КАМIНСЬКА
Strategy of Ukraine : Economics, Sociology, Law , 2011,
Abstract: The question of origin of failures is considered in a global market, influence of TNK on an origin and functioning of such processes. Analysis of redistribution of development of countries. Рассмотрены вопросы возникновения провалов в глобальном рынке, влияние ТНК на возникновение и функционирование таких процессов. Проанализированы перераспределение развития стран. Розглянуто питання виникнення провал в у глобальному ринку, вплив ТНК на виникнення та функц онування таких процес в. Проанал зовано перерозпод л розвитку кра н.
НТЕГРАЦ ЙН ЧИ ДЕЗ НТЕГРАЦ ЙН ПРОЦЕСИ ВРОПИ INTEGRATION OR DISINTEGRATION PROCESSES EUROPE ИНТЕГРАЦИОННЫЕ ИЛИ ДЕЗИНТЕГРАЦИОННЫЕ ПРОЦЕССЫ ЕВРОПЫ
Т.В. КАМIНСЬКА
Strategy of Ukraine : Economics, Sociology, Law , 2011,
Abstract: Розглядаються питання розвитку нтеграц йних процес в в С, а саме основна увага прид лена процесам дез нтеграц , вид ленн основних геопол тичних центр в, та наростанню протир ч у диному економ чному простор м ж кра нами-учасницями. The questions of development of integration processes are examined in ES, namely basic attention is directed on the processes of disintegration, determination of geopolitical centers, to growth of contradictions in single economic space between countries-participants. Рассматриваются вопросы развития интеграционных процессов в ЕС, а именно основное внимание направлено на процессы дезинтеграции, определение геополитических центров, нарастанию проти-воречий в едином экономическом пространстве между странами-участницами.
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