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1.
Phys Rev Lett ; 124(2): 022502, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004016

RESUMO

The ^{7}H system was populated in the ^{2}H(^{8}He,^{3}He)^{7}H reaction with a 26 AMeV ^{8}He beam. The ^{7}H missing mass energy spectrum, the ^{3}H energy and angular distributions in the ^{7}H decay frame were reconstructed. The ^{7}H missing mass spectrum shows a peak, which can be interpreted either as unresolved 5/2^{+} and 3/2^{+} doublet or one of these states at 6.5(5) MeV. The data also provide indications of the 1/2^{+} ground state of ^{7}H located at 1.8(5) MeV with quite a low population cross section of ∼25 µb/sr within angular range θ_{c.m.}≃(17°-27°).

2.
Phys Rev Lett ; 108(20): 202502, 2012 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-23003144

RESUMO

The 0+ ground state of the 10He nucleus produced in the 3H(8He,p)10He reaction was found at about 2.1±0.2 MeV (Γ∼2 MeV) above the three-body ^{8}He+n+n breakup threshold. Angular correlations observed for ^{10}He decay products show prominent interference patterns allowing us to draw conclusions about the structure of low-energy excited states. We interpret the observed correlations as a coherent superposition of a broad 1- state having a maximum at energy 4-6 MeV and a 2+ state above 6 MeV, setting both on top of the 0+ state "tail." This anomalous level ordering indicates that the breakdown of the N=8 shell known in 12Be thus extends also to the ^{10}He system.

3.
Phys Rev Lett ; 99(6): 062502, 2007 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-17930818

RESUMO

The existence of the 7H nuclear system was investigated via a one-proton transfer reaction with a 8He beam at 15.4A MeV and a 12C gas target. The experimental setup was based on the active-target MAYA which allowed a complete reconstruction of the reaction kinematics. The existence of the 7H was confirmed with the identification of seven events where the system was formed with a resonance energy of 0.57(-0.21)(+0.42) MeV above the 3H+4n threshold and a resonance width of 0.09(-0.06)(+0.94) MeV. This study represents an unambiguous proof of the existence of the most neutron-proton unbalanced system presently found.

4.
Phys Rev Lett ; 93(26 Pt 1): 262501, 2004 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-15697971

RESUMO

The 5H system was produced in the 3H(t,p)5H reaction studied with a 58 MeV tritium beam at small c.m. angles. High statistics data were used to reconstruct the energy and angular correlations between the 5H decay fragments. A broad structure in the 5H missing mass spectrum showing up above 2.5 MeV was identified as a mixture of the 3/2+ and 5/2+ states. The data also present evidence that the 1/2+ ground state of 5H is located at about 2 MeV.

5.
Phys Rev Lett ; 87(9): 092501, 2001 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-11531562

RESUMO

Experimental search for (5)H using a secondary beam of (6)He has been performed. The transfer reaction (1)H((6)He,(2)He)(5)H was studied by detecting two protons emitted from the decay of (2)He. A peak consistent with a (5)H resonance at 1.7+/-0.3 MeV above the n+n+t threshold was observed, with a width of 1.9+/-0.4 MeV. The angular distribution of the (1)H((6)He,(2)He)(5)H reaction was measured as well as the energy correlation of the two protons.

7.
Am J Psychiatry ; 153(8): 1084-7, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8678178

RESUMO

A 33-year-old man presented with a 10-year history of psychosis and an imaginary companion; he carried a past diagnosis of chronic schizophrenia. He responded quickly to neuroleptic and was noted to be an easily engageable person. It is argued that despite his first-rank Schneiderian symptoms, the patient may not best be conceptualized as having schizophrenia. Specific treatment recommendations are made, predicated on this man's developmental history, his attachment and separation behavior, and his response to a structured social milieu.


Assuntos
Relações Interpessoais , Esquizofrenia Paranoide/diagnóstico , Adulto , Antipsicóticos/uso terapêutico , Transtorno Autístico/diagnóstico , Transtorno Autístico/psicologia , Doença Crônica , Diagnóstico Duplo (Psiquiatria) , Humanos , Masculino , Esquizofrenia Paranoide/tratamento farmacológico , Esquizofrenia Paranoide/psicologia , Psicologia do Esquizofrênico
8.
Mutat Res ; 211(1): 181-8, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2646531

RESUMO

Uniformly methylated heteroduplex plasmids which contained 6 mismatched regions, including loops of 24, 30, 248 and 283 nucleotides, as well as single-stranded gaps and free ends were introduced into a recombination-deficient strain of bacteria, and the products of repair were analyzed. The results indicate that these cells are capable of repairing all of these structures, although with different efficiencies. Repair of single-stranded gaps and free ends, which occurs most efficiently, is always associated with acquisition of information from the uncut strand (unidirectional repair). Regions containing single loops or twin loops were repaired at similar efficiencies. In these cases each of the two strands was capable of acting as the template for repair (bidirectional repair). At sites containing twin or substitution loops, the larger of the loops was removed twice as efficiently as the smaller loop. DNA sequencing of the repaired regions indicated that the repair is precise. The data also suggest that markers separated by only 58 nucleotides do not always segregate together indicating that repair tracts may be relatively short.


Assuntos
Reparo do DNA , DNA Bacteriano , DNA de Cadeia Simples , Escherichia coli/genética , Conformação de Ácido Nucleico , Composição de Bases , DNA Bacteriano/análise , DNA de Cadeia Simples/análise , Ácidos Nucleicos Heteroduplexes , Plasmídeos , Transformação Genética
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