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1. Doppler-broadening of gamma rays following muon capture: search for scalar coupling

Author

V.B. Brudanin, T. Filipova, Teemu Siiskonen, Yu. Shitov, Jouni Suhonen, C. Petitjean, René Prieels, V. Wiaux, I. Yutlandov, Sh. Zaparov, V. Egorov, Ts. Vylov, Ch. Briançon, Jules Deutsch, Lorgeril, Jocelyne, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, Muon, Correlation coefficient, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], 010308 nuclear & particles physics, Gamma ray, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Impulse (physics), 01 natural sciences, Muon capture, Nuclear physics, Pseudoscalar, 0103 physical sciences, 010306 general physics, Doppler broadening
Abstract

A precision measurement of the 277 keV γ ray produced by capturing muons in gaseous oxygen was performed using high-resolution HPGe detectors. The Doppler-broadened shape of this line is sensitive to the possible admixture into muon capture of genuine scalar interaction. This experiment complements, in the muon sector, in principle, similar ones undertaken recently in nuclear β decay. Using a procedure discussed in earlier papers, a fit to the experimental line-shape allowed us to obtain for the recoil–gamma correlation coefficient the value of a 1 2 =0.096±0.041 (95% CL). The available evaluations of the contributing nuclear matrix elements, performed in the impulse approximation in the absence of scalar interaction, produce correlation coefficients in disagreement with our result. These evaluations are independent of the induced pseudoscalar coupling and so of the validity of the PCAC hypothesis, but their reliability and model dependence remain to be investigated.

Published
2002
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2. Chemical purification of molybdenum samples for the NEMO 3 experiment

Author

V. G. Egorov, X. Sarazin, J. Baker, F. Laplanche, A. S. Barabash, Vit Vorobel, F. Leccia, J.L. Guyonnet, R. Arnold, J.E. Campagne, D. Blum, C. S. Sutton, V. B. Brudanin, I. Linck, I. Nikolic-Audit, C. Longuemare, G. Szklarz, V. F. Kuzichev, J. L. Reyss, V. N. Kornoukhov, I. Stekl, Ts. Vylov, F. Hubert, Ch. Marquet, H. W. Nicholson, C. Augier, I. Vanyushin, V.E. Kovalenko, C. L. Riddle, I. Pilugin, T. Filipova, F. Mauger, E. Caurier, O. Bing, F. Piquemal, V. I. Umatov, A. J. Caffrey, Jouni Suhonen, D. Lalanne, O.I. Kochetov, D. Dassié, F. Scheibling, I. Kisel, K. Errahmane, Vl.I. Tretyak, Ph. Hubert, S. Jullian, and V. V. Timkin

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Spectrometer, chemistry, Molybdenum, Double beta decay, Radiochemistry, chemistry.chemical_element, Germanium, Context (language use), Instrumentation
Abstract

Most currently, viable double beta decay experiments require highly enriched isotopic sources. These sources must be extraordinarily free of radioactive contamination. The double beta decay experiment NEMO 3 will study 100Mo, for which physical and chemical purification techniques have been investigated. The success of the chemical purification process is discussed in the context of ultra-low background, high-purity germanium spectrometer measurements.

Published
2001
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3. Influence of neutrons and γ-rays in the Fréjus underground laboratory on the NEMO experiment

Author

I. Pilugin, O.I. Kochetov, F. Scheibling, F. Leccia, Ch. Marquet, L. Vala, I. Nikolic-Audit, I. Vanyushin, J. Baker, F. Hubert, V. B. Brudanin, V. V. Timkin, A. Vareille, H. Ohsumi, Ts. Vylov, A. S. Barabash, J.E. Campagne, I. Linck, C. Augier, I. Kisel, V. I. Umatov, V.E. Kovalenko, J. Caffrey, F. Mauger, I. Stekl, G. Szklarz, D. Lalanne, C.S. Sutton, Vit Vorobel, V. G. Egorov, C. Jollet, K. Errahmane, Jouni Suhonen, R. Arnold, J.L. Guyonnet, D. Blum, J. L. Reyss, V. N. Kornoukhov, H. W. Nicholson, Vl.I. Tretyak, D. Dassié, T. Filipova, E. Caurier, Ph. Hubert, F. Laplanche, O. Bing, C. Longuemare, S. Jullian, X. Sarazin, R. Eschbach, and F. Piquemal

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, MAJORANA, Particle physics, Photomultiplier, Beta (plasma physics), Double beta decay, Monte Carlo method, Detector, Neutron, Neutrino, Instrumentation
Abstract

To be sensitive to an effective Majorana neutrino mass, 〈 m ν 〉, on the order of 0.1 eV, the NEMO 3 double beta (ββ(0ν)) decay experiment requires precise knowledge and control of the backgrounds. The effect of neutrons and γ-rays from the Frejus underground laboratory (LSM, Laboratoire Souterrain de Modane) has been studied during 10 700 h of data collection. The data were taken with a NEMO 2 prototype detector using different shield configurations. Monte Carlo calculations with GEANT/MICAP code and a new library of γ-rays from neutron captures are presented. The implied consequences for the NEMO 3 detector which is under construction are discussed. The neutrinoless double beta decay background induced by neutrons and γ-rays within the LSM will be suppressed to the very suitable level of 0.1 event in a live time of five years given the appropriate shield and magnetic field.

Published
2001
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4. Limits on different Majoron decay modes of Mo, Cd, Se and Zr for neutrinoless double beta decays in the NEMO-2 experiment

Author

Ph. Hubert, Rodolfo Gurriaran, I. Linck, S. Jullian, F. Laplanche, C.S. Sutton, V. G. Egorov, F. Leccia, X. Sarazin, H. Nicholson, V. V. Timkin, D. Lallane, A. J. Caffrey, D. Dassié, J. Baker, V. Vasiliev, R. Arnold, V. B. Brudanin, F. Scheibling, I. Pilyugin, G. Szklarz, I. Vanyushin, T. Filipova, E. Caurier, Ch. Marquet, V. I. Umatov, I. Kisel, D. Blum, A. S. Barabash, A. Vareille, C. Longuemare, J.L. Guyonnet, J.E. Campagne, J. L. Reyss, V. N. Kornoukhov, C. Augier, Jouni Suhonen, Ts. Vylov, V.E. Kovalenko, F. Mauger, R. Torres, O.I. Kochetov, F. Piquemal, and F. Hubert

Subjects
Nuclear physics, Coupling constant, Physics, Nuclear and High Energy Physics, Particle physics, Double beta decay, Detector, Underground laboratory, Beta (velocity), Lower limit, Majoron
Abstract

The NEMO-2 tracking detector located in the Frejus Underground Laboratory was designed as a prototype for the NEMO-3 detector and to study different modes of double beta decay. Measurements with 100 Mo, 116 Cd, 82 Se and 96 Zr were carried out. Presented here are the experimental half-life limits on double beta decays for new Majoron emission modes and limits on effective neutrino–Majoron coupling constants.

Published
2000
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5. The spin-neutrino correlation revisited in 28Si muon capture: a new determination of the induced pseudoscalar coupling gP/gA

Author

A. Pasternak, V. Lobanov, A.V. Salamatin, T. Filipova, V.B. Brudanin, M. Kudoyarov, Yu. Shitov, I. Yutlandov, T. Mamedov, Ts. Vylov, J. Deutsch, Sh. Zaparov, René Prieels, V. Egorov, and Ch. Briançon

Subjects
Nuclear physics, Physics, Pseudoscalar, Nuclear and High Energy Physics, Muon, Neutrino, Muon spin spectroscopy, Atomic physics, Nucleon, Coupling (probability), Muon capture, Spin-½
Abstract

We describe an improved follow-up of our previous spin-neutrino correlation experiment, where the 1229 and 2171 keV gamma-rays emitted after the 28 Si( μ , ν ) 28 Al(1 + , 2202 keV) reaction were observed by high-resolution HPGe detectors at different angles with respect to the muon spin. In the experiment described here, a magnetic field was used both to select events according to the spin-gamma angle and to measure the residual muon polarization by the muSR method. We further increase the precision of our result making use of new experimental and theoretical information. We obtain for the parameter x ≡ M (2)/ M (−1) the value of x =0.239±0.029, which can be compared to our previous result (Brudanin et al., Nucl. Phys. A 587 (1995) 577) x =0.254±0.034 and to the value x =0.315±0.080 obtained recently at TRIUMF with a different technique. The coupling-constant ratio g P / g A was deduced from the mean value x =0.247±0.027. Using renormalized transition operators calculated recently, we obtained for g P / g A the solution range of −1.0 to +1.3 to be compared to the value of 7 predicted by PCAC for the free nucleon. This result confirms the strong quenching of g P / g A reported earlier.

Published
2000
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6. Technical design and performance of the NEMO 3 detector

Author

I. Nikolic-Audit, R. Igersheim, F. Piquemal, I. Kisel, A. Guiral, I. Linck, A. A. Klimenko, V. B. Brudanin, C. Augier, V. V. Timkin, F. Scheibling, J.L. Guyonnet, J. L. Reyss, G. Szklarz, S. I. Vasiliev, V.E. Kovalenko, G. Martin-Chassard, P. Imbert, A. S. Barabash, S. V. Zhukov, F. Mauger, Igor Nemchenok, J.E. Campagne, I. Vanushin, J. Forget, C. Jollet, F. Hubert, L. Simard, P. Guiral, L. Vala, F. Leccia, S. Pécourt, O.I. Kochetov, J. Lebris, I. Stekl, J. Wurtz, Vl.I. Tretyak, M. Bouchel, A. M. Bakalyarov, V. I. Lebedev, B. Humbert, B. Lavigne, K. Errahmane, D. Dassié, A.I. Etienvre, D. Lalanne, Yu. Shitov, Vit Vorobel, Ph. Bernaudin, A. Leconte, C. L. Riddle, V. G. Egorov, T. Filipova, V. Vasilyev, J. Baker, V. I. Umatov, R. Arnold, Ch. Marquet, S. Jullian, A. Richard, Ts. Vylov, J. Rypko, X. Sarazin, A. J. Caffrey, Ph. Hubert, H. Ohsumi, C. Longuemare, A.A. Smolnikov, J. Cailleret, F. Laplanche, C.S. Sutton, Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), NEMO, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Tracking detector, Physics::Instrumentation and Detectors, Nuclear engineering, FOS: Physical sciences, 01 natural sciences, Technical design, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), NEMO, Double beta decay, 0103 physical sciences, Neutrino, Neutrino Ettore Majorana Observatory, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010306 general physics, Instrumentation, Physics, Calorimeter, 010308 nuclear & particles physics, Detector, Astrophysics::Instrumentation and Methods for Astrophysics, Instrumentation and Detectors (physics.ins-det), 23.40.−s, 14.60.Pq, Underground laboratory, High Energy Physics::Experiment, Majorana
Abstract

The development of the NEMO3 detector, which is now running in the Frejus Underground Laboratory (L.S.M. Laboratoire Souterrain de Modane), was begun more than ten years ago. The NEMO3 detector uses a tracking-calorimeter technique in order to investigate double beta decay processes for several isotopes. The technical description of the detector is followed by the presentation of its performance., Preprint submitted to Nucl. Instrum. Methods A Corresponding author: Corinne Augier (augier@lal.in2p3.fr)

Published
2005
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7. Electromyographic investigations of tremor in aquanauts during simulated immersions

Author

D. T. Filipova

Subjects
Adult, Atmosphere Exposure Chambers, medicine.medical_specialty, Electromyography, Nitrogen, Decompression, business.industry, Diving, Muscles, General Neuroscience, Neon, Parkinson Disease, Helium, Pressure level, nervous system diseases, Trimix, Oxygen, Physical medicine and rehabilitation, Immersion, Tremor, medicine, Humans, business
Abstract

Electromyographic investigations of tremor in aquanauts under the conditions of stimulated immersions are presented in this paper. The investigations were carried out before the aquanauts entered a barochamber, at specific pressure levels in the barochamber, under the conditions of decompression, and following emergence from the barochamber. The observed manifestations of the tremor under the conditions of increased pressure of trimix exhibited characteristics of parkinsonian tremor.

Published
1993
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8. Electromyographic activity of the respiratory muscles in hyperbaric conditions

Author

D. T. Filipova

Subjects
Adult, Male, medicine.medical_specialty, Atmosphere Exposure Chambers, Diving, Diaphragm, Difficulty breathing, Intercostal Muscles, Neon, Electromyography, Helium, Physical medicine and rehabilitation, medicine, Humans, Respiratory system, Air Pressure, medicine.diagnostic_test, business.industry, General Neuroscience, Neurophysiology, Respiratory Muscles, Electrophysiology, Oxygen, Physical therapy, business
Abstract

Divers are known to have difficulty breathing in conditions of increased respiratory gas density. This report presents results obtained from electromyographic studies of the inspiratory muscles in conditions imitating a pressure chamber using neon and helium. Electromyographic investigations of the respiratory muscles allows the roles of these muscles in the respiratory act to be assessed and the present study is an attempt to demonstrate the possible neurophysiological mechanisms of respiratory difficulty in high-pressure conditions.

Published
2000

9. Double beta decay of $^{96}$Zr

Author

A. J. Caffrey, Ph. Hubert, F. Hubert, Vl.I. Tretyak, V.E. Kovalenko, F. Mauger, F. Piquemal, F. Laplanche, R. Torres, S. Jullian, A. S. Barabash, O.I. Kochetov, D. Blum, F. Leccia, I. Linck, C. Longuemare, V. G. Egorov, X. Sarazin, Jouni Suhonen, T. Filipova, A. Vareille, E. Caurier, J. Baker, V. B. Brudanin, D. Dassié, Ts. Vylov, Yu. Vasilyev, I. Pilugin, R. Arnold, C. Augier, I. Vanyushin, D. Lalanne, J.L. Guyonnet, J.E. Campagne, J. L. Reyss, V. N. Kornoukhov, H. W. Nicholson, I. Kisel, V. I. Umatov, C. S. Sutton, G. Szklarz, Ch. Marquet, F. Scheibling, V. V. Timkin, Rodolfo Gurriaran, Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), NEMO, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, Zirconium, 010308 nuclear & particles physics, chemistry.chemical_element, 01 natural sciences, Lower limit, Nuclear physics, Angular distribution, chemistry, Double beta decay, Excited state, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Atomic physics, 010306 general physics, Ground state, Majoron
Abstract

After 10357 h of running the NEMO-2 tracking detector with an isotopically enriched zirconium source (0.084 mol yr of 96Zr), a ββ2ν decay half-life of T1/2=(2.1+0.8(stat)−0.4(stat)±0.2(syst))·1019 y was measured. Limits with a 90% C.L. on the 96Zr half-lives of 1.0·1021 y for ββ0ν decay to the ground state, 3.9·1020 y to the 2+ excited state and 3.5·1020 y for ββ0νχ0 decay with a Majoron (χ0) were obtained. The data also provide direct limits at the 90% C.L. for the 94Zr half-lives. These limits are 1.1·1017 y for ββ2ν decay to the ground state, 1.9·1019 y for ββ0ν decay to the ground state and 2.3·1018 y for ββ0νχ0 decay to ground state.

Published
1999

10. Measurement of the induced pseudoscalar form factor in the capture of polarized muons by Si nuclei

Author

A.V. Salamatin, T. Filipova, V.E. Kovalenko, V. B. Brudanin, V. Vorobel, I. Stekl, Ch. Briançon, A Kachalkin, V. G. Egorov, J. Rak, René Prieels, I. Yutlandov, L. Grenacs, Ts. Vylov, S. Vassiliev, Yu. Shitov, Jules Deutsch, Sh. Zaparov, Lorgeril, Jocelyne, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Quenching (fluorescence), Muon, Silicon, 010308 nuclear & particles physics, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], Form factor (quantum field theory), chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Coupling (probability), 01 natural sciences, Pseudoscalar, chemistry, 0103 physical sciences, Atomic physics, 010306 general physics, Nuclear Physics
Abstract

The observation with high-resolution Ge detectors of the 1229 and 2171 keV gamma-rays emitted after the 28Si(μ, ν)28Al(1+, 2202 keV) reaction allowed us to determine the nuclear-amplitude ratio x ≡ M(2) M(−1) characteristic of this muon-capture reaction. Using the nuclear-structure dependent evaluation of various correction terms (model of Ciechanowicz), our result x = +0.254±0.034 provides for the induced pseudoscalar coupling gp the ratio g p g a (0.848m μ 2 ) = 3.4 ± 1.0 , to be compared to the PCAC prediction of g p g a = 7 . The model dependence of this apparent quenching remains to be assessed.

Published
1994

12. Testing the Pauli exclusion principle with the NEMO-2 detector

Author

F. Laplanche, Ts. Vylov, V. B. Brudanin, F. Leccia, J. Baker, V. V. Timkin, V.E. Kovalenko, V. G. Egorov, X. Sarazin, F. Mauger, R. Torres, D. Dassié, A. J. Caffrey, E. Caurier, Ph. Hubert, C. Longuemare, O.I. Kochetov, R. Arnold, Yu. Vasilyev, I. Pilugin, Rodolfo Gurriaran, S. Jullian, T. Filipova, F. Scheibling, I. Vanyushin, F. Hubert, F. Piquemal, C. S. Sutton, Jouni Suhonen, G. Szklarz, C. Augier, D. Blum, Ch. Marquet, A. Vareille, I. Linck, J.L. Guyonnet, J.E. Campagne, J. L. Reyss, V. N. Kornoukhov, H. W. Nicholson, A. S. Barabash, D. Lalanne, I. Kisel, V. I. Umatov, and Vl.I. Tretyak

Subjects
Physics, Nuclear and High Energy Physics, Hadron, Carbon-12, Isotopes of boron, Particle detector, Nuclear physics, symbols.namesake, Pauli exclusion principle, Double beta decay, symbols, Nucleon, Radioactive decay, Nuclear Physics
Abstract

The Pauli Exclusion Principle (PEP) was tested with the NEMO-2 detector. Limits at the 90% C.L. on the violation of PEP for p-shell nucleons in 12C were obtained. Specifically, transitions to the fully occupied 1s1/2-shell yielded a limit of 4.2 · 1024 y for the process with emission of a γ-quantum. Similarly limits of 3.1 · 1024 y for β− and 2.6 · 1024 y for β+ Pauli-forbidden transitions of 12C →12N12B) are reported here.

13. Double-β decay of 82Se

Author

Ph. Hubert, S. Jullian, A. J. Caffrey, V. B. Brudanin, C. Augier, F. Laplanche, E. Caurier, V. Zerkin, O. Purtov, Ts. Vylov, D. Dassié, F. Leccia, R. Arnold, O.I. Kochetov, D. Blum, F. Hubert, D. Lalanne, Yu. Vasilyev, I. Pilugin, P. Mennrath, V. G. Egorov, I. Linck, X. Sarazin, J. Baker, V.I. Tretyak, T. Filipova, A. Vareille, A. S. Barabash, J.L. Guyonnet, J.E. Campagne, J. L. Reyss, V. N. Kornoukhov, H. W. Nicholson, I. Vanyushin, I. Kisel, Jouni Suhonen, F. Scheibling, C. S. Sutton, G. Szklarz, Ch. Marquet, V.E. Kovalenko, F. Mauger, R. Torres, Rodolfo Gurriaran, R. Eschbach, V. V. Timkin, V. I. Umatov, C. Longuemare, and F. Piquemal

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Isotopes of selenium, Double beta decay, Excited state, Half-life, Neutrino, Beta decay, Radioactive decay, Majoron
Abstract

The NEMO-2 tracking detector located in the Frejus Underground Laboratory was designed as a prototype of the NEMO-3 detector to study neutrinoless (Oν) and two neutrino (2ν) double-beta decay (ββ) physics. After 10357 h of running with an isotopically enriched selenium source (2.17 mol yr of 82Se) a ββ2ν decay half-life of T 1 2 = (0.83 ± 0.10( stat ) ± 0.07 ( syst )) × 10 20 yr was measured. Limits with a 90% C.L. on the 82Se half-lives of 9.5 × 1021 yr for ββ0ν decay to the ground state, 2.8 × 1021 yr to the (2+) excited state and 2.4 × 1021 yr for ββ0νχ0 decay with a Majoron (χ0) were also obtained.

14. Multidrug- and Extensively Drug-Resistant Mycobacterium tuberculosis Beijing Clades, Ukraine, 2015.

Author

Merker M, Nikolaevskaya E, Kohl TA, Molina-Moya B, Pavlovska O, Brännberg P, Dudnyk A, Stokich V, Barilar I, Marynova I, Filipova T, Prat C, Sjöstedt A, Dominguez J, Rzhepishevska O, and Niemann S

Subjects
Adult, Antitubercular Agents pharmacology, Antitubercular Agents therapeutic use, Contact Tracing, Drug Resistance, Multiple, Bacterial genetics, Extensively Drug-Resistant Tuberculosis drug therapy, Extensively Drug-Resistant Tuberculosis etiology, Female, Humans, Male, Middle Aged, Mycobacterium tuberculosis drug effects, Tuberculosis, Multidrug-Resistant drug therapy, Tuberculosis, Multidrug-Resistant epidemiology, Tuberculosis, Multidrug-Resistant etiology, Tuberculosis, Pulmonary drug therapy, Tuberculosis, Pulmonary etiology, Ukraine epidemiology, Urban Population, Extensively Drug-Resistant Tuberculosis epidemiology, Mycobacterium tuberculosis genetics, Tuberculosis, Pulmonary epidemiology
Abstract

Multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) is an emerging threat to TB control in Ukraine, a country with the third highest XDR TB burden globally. We used whole-genome sequencing of a convenience sample to identify bacterial genetic and patient-related factors associated with MDR/XDR TB in this country. MDR/XDR TB was associated with 3 distinct Mycobacterium tuberculosis complex lineage 2 (Beijing) clades, Europe/Russia W148 outbreak, Central Asia outbreak, and Ukraine outbreak, which comprised 68.9% of all MDR/XDR TB strains from southern Ukraine. MDR/XDR TB was also associated with previous treatment for TB and urban residence. The circulation of Beijing outbreak strains harboring broad drug resistance, coupled with constraints in drug supply and limited availability of phenotypic drug susceptibility testing, needs to be considered when new TB management strategies are implemented in Ukraine.

Published
2020
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15. Characteristics of the Pseudomonas aeruginosa PA01 Intercellular Signaling Pathway (Quorum Sensing) Functioning in Presence of Porphyrins Bismuth Complexes.

Author

Galkin M, Ivanitsia V, Ishkov Y, Galkin B, and Filipova T

Subjects
Anti-Bacterial Agents chemistry, Bismuth chemistry, Molecular Structure, Porphyrins chemistry, Anti-Bacterial Agents pharmacology, Bismuth pharmacology, Porphyrins pharmacology, Pseudomonas aeruginosa physiology, Quorum Sensing physiology
Abstract

The influence of synthetic and natural porphyrins bismuth complexes on P. aeruginosa quorum sensing system was carried out by detection of the pyocyanin, rhamnolipids and autoinducers biosynthesis level. The highest ability to reduce pyocyanin biosynthesis showed Bi(III)-TPP. Rhamnolipids production level also decreased in the presence of studied compounds. This effect was the most expressed in presence of 40 and 80 µM of the synthetic meso-substituted porphyrins. Autoinducers biosynthesis, especially 3-oxo-C12-HSL was suppressed in presence of the bismuth complexes. That suggest that the mechanisms of action of this substances is an inhibition of signaling molecules or/and receptor for them.

Published
2015

16. Inhibition of lactophage activity by quinolinilporphyrin and its zinc compex.

Author

Vodzinska N, Galkin B, Ishkov Y, Kirichenko A, Kondratyuk A, and Filipova T

Subjects
Antiviral Agents pharmacology, Bacteriophages drug effects, Lactococcus lactis virology, Metalloporphyrins pharmacology, Porphyrins pharmacology, Quinolinium Compounds pharmacology
Abstract

The influence of free base of quinolinilporphyrin and its Zn complex on infectivity of lactophages E3, E5 and E17 has been studied. The results of our investigations show that inhibition of lactophage activity by Zn complex of quinolinilporphyrin at concentration 10 microM and 20 microM was in the range 53-62% and 65-85%, respectively. The presence of this porphyrin in nutrient medium prevents the propagation of bacteriophage infection in Lactococcus lactis, but does not affect the phage adsorption process. The free base of quinolinilporphyrin slightly inhibits the activity of lactophages.

Published
2011

17. Role of LHCII organization in the interaction of substituted 1,4-anthraquinones with thylakoid membranes.

Author

Apostolova E, Krumova S, Markova T, Filipova T, Molina MT, Petkanchin I, and Taneva SG

Subjects
Mutation genetics, Pisum sativum enzymology, Pisum sativum genetics, Photochemistry, Photosystem II Protein Complex genetics, Spectrometry, Fluorescence, Static Electricity, Anthraquinones chemistry, Anthraquinones metabolism, Photosystem II Protein Complex chemistry, Photosystem II Protein Complex metabolism, Thylakoids metabolism
Abstract

The chlorophyll fluorescence, photochemical activity and surface electric properties of thylakoid membranes with different stoichiometry of pigment-protein complexes and organization of the light-harvesting chlorophyll a/b protein complex of photosystem II (LHCII) were studied in the presence of substituted 1,4-anthraquinones. Data show strong dependence of the quenching of the chlorophyll fluorescence on the structural organization of LHCII. The increase of the LHCII oligomerization, which is associated with significant reduction of the transmembrane electric charge asymmetry and electric polarizability of the membrane, correlates with enhanced quenching effect of substituted 1,4-athraquinones. Crucial for the large quinone-induced changes in the membrane electric dipole moments is the structure of the quinone molecule. The strongest reduction in the values of the dipole moments is observed after interaction of thylakoids with 3-chloro-9-hydroxy-1,4-anthraquinone (TF33) which has the highest quenching efficiency. The quinone induced changes in the photochemical activity of photosystem II (PSII) correlate with the total amount of the supramolecular LHCII-PSII complex and depend on the number of substituents in the 1,4-anthraquinone molecule.

Published
2005
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18. Influence of substituted 1,4-anthraquinones on the chlorophyll fluorescence and photochemical activity of pea thylakoid membranes.

Author

Apostolova E, Markova T, Filipova T, Molina MT, and Taneva SG

Subjects
Electrons, Photochemistry, Spectrometry, Fluorescence, Anthraquinones chemistry, Chlorophyll chemistry, Pisum sativum chemistry, Thylakoids chemistry
Abstract

The effect of substituted 1,4-anthraquinones on the photochemical activity and chlorophyll fluorescence of thylakoid membranes was examined. Both the fluorescence and the photochemical activity depend on the 1,4-anthraquinone substituent. Stronger quinone-induced quenching of the chlorophyll fluorescence than quinone-induced changes in the activity of photosystem II is observed. The type (Cl or Br) and the position (Cl) of the chalogen atom strongly influence the degree of inhibition of PSII electron transport and the quenching of chlorophyll fluorescence. The data suggest that the quenching of chlorophyll fluorescence is due rather to the interaction of the 1,4-anthraquinones and chlorophyll molecules than to an indirect effect caused by stimulation of the photochemistry.

Published
2003
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