11. |
- Fomichev, A. S., et al.
(författare)
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Lifetime of 26S and a Limit for its 2p Decay Energy
- 2011
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Ingår i: International Journal of Modern Physics E. - : World Scientific Pub Co Pte Lt. - 0218-3013 .- 1793-6608. ; 20:6, s. 1491-1508
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Tidskriftsartikel (refereegranskat)abstract
- The unknown isotope (26)S, expected to decay by two-proton (2p) emission, was studied theoretically and searched experimentally. The structure of this nucleus was examined within the relativistic mean field (RMF) approach. A method for taking into account the many-body structure in the three-body decay calculations was developed. The results of the RMF calculations were used as an input for the three-cluster decay model optimized for the study of a possible 2p decay branch of this nucleus. The experimental search for (26)S was performed by fragmentation of a 50.3 A MeV (32)S beam. No events of a particles table (26)S or (25)P (a presumably proton-unstable subsystem of (26)S) were observed. Based on the obtained production systematics, an upper half-life limit of T(1/2) 640 keV for (26)S. Analogous limits for (25)P are found as T(1/2) 110 keV. In the case that the one-proton emission is the main branch of the (26)S decay, a limit Q(2p) > 230 keV would follow for this nucleus. According to these limits, it is likely that (26)S resides in the picosecond life time range
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12. |
- Fomichev, A. S., et al.
(författare)
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Recent results related to excited states of 6Be and 10He
- 2012
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Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 38, s. Art. no. 15002-
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Konferensbidrag (refereegranskat)abstract
- The 1H(6Li,6Be)n charge-exchange reaction and the 3H(8He, p)10He two-neutron transfer reaction were recently carried out at the ACCULINNA fragment separator (FLNR, Dubna) to populate the ground and excited states of 6Be and 10He nuclei, respectively. The 6Be ET spectrum (ET is the 6Be energy above its 4He+p+p decay threshold) was obtained with high statistics and described by the well-known 0+ ground state of 6Be at ET = 1.37 MeV, the 2+ state at ET = 3.05 MeV and a broad structure extending from 4 to 16 MeV which could be interpreted as the isovector soft dipole mode associated with the 6Li ground state. In the 10He case the 0+ ground state was found at about 2.1(2) MeV (T ∼ 2 MeV) above the 8He+n+n breakup threshold. Angular correlations observed for 10He decay products show prominent interference patterns allowing to draw conclusions about the structure of low-energy excited states: 1- (E T ∼ 5 MeV) and 2+ (ET > 6 MeV).
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13. |
- Krupko, S. A., et al.
(författare)
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The status of new fragment separator ACCULINNA-2 project and the first day experiments
- 2014
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Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
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Konferensbidrag (refereegranskat)abstract
- The new facility fragment separator ACCULINNA-2 will be put into operation at the beginning of 2015 in FLNR JINR. The new separator is destined to add considerably to the studies of drip-line nuclei performed with the use of variety of direct reactions known to be distinctive to the 15 - 50 MeV/amu exotic secondary RIBs. Intense beams provided by the U-400M cyclotron will ensure the achievement of this objective. In addition to the RIB separation accomplished by means of the dipole-wedge-dipole selection, the addition of a zero-degree dipole magnet setup is foreseen. A long (13 m) straight section will provide precise time-of-flight measurements. © Owned by the authors, published by EDP Sciences, 2014.
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14. |
- Thompson, T.M, et al.
(författare)
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Genetic variation in DRD4, criminality and conduct disorder
- 2011
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Ingår i: Personality and individual differences. - New York : Nova Science Publishers Inc.. - 9781611225884
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Bokkapitel (refereegranskat)abstract
- Personality and individual differences research is relevant to practically every facet of human existence. For instance, since theories of persons either explicitly or implicitly guide clinical work, the field contributes to discussions of understanding abnormal psychology and provides a guide for conceptualising best treatment. Additionally, the field is relevant to understanding human development across the lifespan, and our understanding of personality and individual differences impacts upon our views of socialisation and interpersonal relations. This book presents research which draws attention to the rich scientific literature that continues to emerge with respect to personality and individual differences psychology.
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15. |
- DeYoung, Colin G., et al.
(författare)
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Variation in the catechol-O-methyltransferase Val(158)Met polymorphism associated with conduct disorder and ADHD symptoms, among adolescent male delinquents
- 2010
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Ingår i: Psychiatric Genetics. - 0955-8829 .- 1473-5873. ; 20:1, s. 20-24
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Tidskriftsartikel (refereegranskat)abstract
- Objective Variation in the catechol-O-methyltransferase gene (COMT) has been associated with antisocial behavior in populations with attention deficit/hyperactivity disorder (ADHD). This study examined whether COMT would predict antisocial behavior in a sample with high levels of behavior problems, not necessarily ADHD. In addition, because previous research suggests that COMT may be associated with ADHD in males, association between COMT and ADHD symptoms was examined. Method This study tested whether variation in three polymorphisms of the COMT gene was predictive of symptoms of conduct disorder and ADHD, in a sample of 174 incarcerated Russian adolescent male delinquents. Results The Val allele of the Val(158)Met polymorphism was significantly associated with conduct disorder diagnosis and symptoms, whereas the Met allele was associated with ADHD symptoms. Conclusion The Val(158)Met polymorphism of the COMT gene shows a complex relation to behavior problems, influencing conduct disorder and ADHD symptoms in opposite directions in a high-risk population. Psychiatr Genet 20:20-24 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.
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16. |
- Ershov, S. N., et al.
(författare)
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Halo formation and breakup: lessons and open questions
- 2010
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Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 37:6
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Tidskriftsartikel (refereegranskat)abstract
- A quarter of a century's concerted international work in halo physics has resulted in an extended nuclear paradigm encompassing the limits of existence of cold nuclei and also structures beyond-continuum structures of open (nuclear) quantum systems. Realistic working models, based on cluster constituents, have sprung out of the very nature of halo phenomena, in particular from the three-body Borromean property of two-neutron halos, the lack of low-lying binary breakup channels. This has provided transparency and possibility for insight into new quantum behaviour, also in continua beyond driplines-a focus of this status assessment. Breakup spectra and progressively exclusive correlation cross sections can be computed and show, where relevant data exist, not only that general agreement is encouraging but also that some exclusive observables exhibit significant disagreement that has to be clarified. Progress in studies of two-proton emitters has provided another pathway beyond driplines, where again few-body theory appears promising.
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17. |
- Fomichev, A. S., et al.
(författare)
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Long range plan with radioactive beams at Dubna
- 2010
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Ingår i: 3rd International Conference on Current Problems in Nuclear Physics and Atomic Energy, NPAE 2010; Kyiv; Ukraine; 7 June 2010 through 12 June 2010. ; , s. 64-69
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Konferensbidrag (refereegranskat)abstract
- A program for upgrade of existing radioactive ion beams facilities at Flerov Laboratory of Nuclear Reactions, JINR Dubna is presented. A project of a new in-flight fragment separator ACCULINNA-2 is proposed. It is expected the new instrument will be more universal and powerful than the existing nowadays. The beam intensity should be increased by factor 10-15, its optical quality greatly improved and the range of the accessible secondary radioactive beams broadened up to Z∼20. Main ion-optical characteristics, operating principles and a tentative plan for the project realization are included. An extensive research program based on local experiments made so far and international proposals for these equipments is discussed.
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18. |
- Fomichev, A. S., et al.
(författare)
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The Suggested New Fragment Separator ACCULINNA-2
- 2010
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Ingår i: Acta Physica Polonica, Series B.. - 1509-5770 .- 0587-4254. ; 41:2, s. 475-480
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Tidskriftsartikel (refereegranskat)abstract
- We present new project of fragment separator ACCULINNA-2 that is being planned to be constructed in Flerov Laboratory of Nuclear Reaction, JINR. The ACCULINNA-2 facility is not, intended to compete with the, new large in-flight RIB facilities. It, should complement the existing/constructed facilities in certain fields. Namely, ACCULINNA-2 should provide high intensity RIBs in the lowest energy range attainable for in-flight separators.
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19. |
- Grigorenko, E. E., et al.
(författare)
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THEMIS observations of the current sheet dynamics in response to the intrusion of the high-velocity plasma flow into the near-Earth magnetotail
- 2014
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Ingår i: Journal of Geophysical Research - Space Physics. - 2169-9380 .- 2169-9402. ; 119:8
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Tidskriftsartikel (refereegranskat)abstract
- A small separation between Time History of Events and Macroscale Interactions during Substorms (THEMIS) probes allows us to analyze a sudden activation in the near-Earth current sheet (CS) at microscales. The start of the activation coincides with the appearance of an earthward plasma flow and dipolarization front (DF) at THEMIS location. The time sequence of observations of the fast plasma flow and the associated DF by three THEMIS probes denotes their dawnward displacement and the localization of the flow channel in the dawn-dusk direction. The onset of kink perturbations of the CS was generated on the dawn side of the flow. These fluctuations also propagated dawnward and were followed by the CS thinning (L similar to rho(i)) and by the development of tearing instability with transient appearance of a magnetic null point. The region of the unstable CS with a magnetic null point was localized in the X and, possibly, in the Y directions. The CS perturbations were most likely triggered by the intrusion of the fast flow into the ambient plasma in the course of the global dawnward displacement of the flow structure. Although no substorm onset was observed during the CS activation, a ground signature of a pseudobreakup was detected just after the excitement of the tearing mode in the near-Earth tail. Probably the pseudobreakup was caused by a localized diversion of the current, which could result from the disruption of the cross-tail current in a localized region of the near-Earth CS.
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20. |
- Grigorenko, Elena L., et al.
(författare)
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Aggressive behaviour, related conduct problems, and variation in genes affecting dopamine turnover
- 2010
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Ingår i: Aggressive Behavior. - : Wiley. - 0096-140X .- 1098-2337. ; 36:3, s. 158-176
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Tidskriftsartikel (refereegranskat)abstract
- A number of dopamine-related genes have been implicated in the etiology of violent behavior and conduct problems. Of these genes, the ones that code for the enzymes that influence the turnover of dopamine (DA) have received the most attention. In this study, we investigated 12 genetic polymorphisms in four genes involved with DA functioning (COMT, MAOA and MAOB, and DβH) in 179 incarcerated male Russian adolescents and two groups of matched controls: boys without criminal records referred to by their teachers as (a) “troubled-behavior-free” boys, n=182; and (b) “troubled-behavior” boys, n=60. The participants were classified as (1) being incarcerated or not, (2) having the DSM-IV diagnosis of conduct disorder (CD) or not, and (3) having committed violent or nonviolent crimes (for the incarcerated individuals only). The findings indicate that, although no single genetic variant in any of the four genes differentiated individuals in the investigated groups, various linear combinations (i.e., haplotypes) and nonlinear combinations (i.e., interactions between variants within and across genes) of genetic variants resulted in informative and robust classifications for two of the three groupings. These combinations of genetic variants differentiated individuals in incarceration vs. nonincarcerated and CD vs. no-CD groups; no informative combinations were established consistently for the grouping by crime within the incarcerated individuals. This study underscores the importance of considering multiple rather than single markers within candidate genes and their additive and interactive combinations, both with themselves and with nongenetic indicators, while attempting to understand the genetic background of such complex behaviors as serious conduct problems.
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