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1.
Sci Rep ; 13(1): 8193, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37210425

RESUMO

Thermomagnetic properties, and its effects on Fisher information entropy with Schioberg plus Manning-Rosen potential are studied using NUFA and SUSYQM methods in the presence of the Greene-Aldrich approximation scheme to the centrifugal term. The wave function obtained was used to study Fisher information both in position and momentum spaces for different quantum states by the gamma function and digamma polynomials. The energy equation obtained in a closed form was used to deduce numerical energy spectra, partition function, and other thermomagnetic properties. The results show that with an application of AB and magnetic fields, the numerical energy eigenvalues for different magnetic quantum spins decrease as the quantum state increases and completely removes the degeneracy of the energy spectra. Also, the numerical computation of Fisher information satisfies Fisher information inequality products, indicating that the particles are more localized in the presence of external fields than in their absence, and the trend shows complete localization of quantum mechanical particles in all quantum states. Our potential reduces to Schioberg and Manning-Rosen potentials as special cases. Our potential reduces to Schioberg and Manning-Rosen potentials as special cases. The energy equations obtained from the NUFA and SUSYQM were the same, demonstrating a high level of mathematical precision.

2.
Phys Rev Lett ; 109(18): 183001, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23215275

RESUMO

We demonstrate rotational and vibrational cooling of cesium dimers by optical pumping techniques. We use two laser sources exciting all the populated rovibrational states, except a target state that thus behaves like a dark state where molecules pile up thanks to absorption-spontaneous emission cycles. We are able to accumulate photoassociated cold Cs(2) molecules in their absolute ground state (v = 0, J = 0) with up to 40% efficiency. Given its simplicity, the method could be extended to other molecules and molecular beams. It also opens up general perspectives in laser cooling the external degrees of freedom of molecules.

3.
Phys Chem Chem Phys ; 13(42): 18910-20, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21814669

RESUMO

Translationally cold caesium molecules are created by photoassociation below the 6s + 6p(1/2) excited state and selectively detected by resonance enhanced two photon ionization (RE2PI). A series of excited vibrational levels belonging to the 0(-)(g) symmetry is identified. The regular progression of the vibrational spacings and of the rotational constants of the 0(-)(g) (6s + 6p(1/2)) levels is strongly altered in two energy domains. These deviations are interpreted in terms of resonant coupling with deeply bound energy levels of two upper 0(-)(g) states dissociating into the 6s + 6p(3/2) and 6s + 5d(3/2) asymptotes. A theoretical model is proposed to explain the coupling and a quantum defect analysis of the perturbed level position is performed. Moreover, the resonant coupling changes dramatically the spontaneous decay products of the photoexcited molecules, strongly enhancing the decay into deeply bound levels of the a(3)Σ(+)(u) triplet state and of the X(1)Σ(+)(g) ground state. These results may be relevant when conceiving population transferring schemes in cold molecule systems.

5.
Arch Pediatr ; 13(9): 1239-43, 2006 Sep.
Artigo em Francês | MEDLINE | ID: mdl-16854573

RESUMO

UNLABELLED: Based on a case report of aplastic anemia associated with malformation, we discuss the diagnostic criteria and the nosologic problem between the 2 principal aplastic anemia accompanied with malformation: Fanconi disease and dyskeratosis congenita. CASE REPORT: A 19-year-old girl, issued from a third degree consanguineous marriage, was admitted because of anemic and hemorrhagic syndrome. Physical examination showed several malformations: microphtalmia, brownish spots, generalized hyperpigmentation and ungueal dystrophy without mucosal leucoplasia. Statural and ponderal retardation were noted. On the hemogram there was a pancytopenia and on biopsy, the bone marrow was desertic. The caryotype performed on peripheral blood lymphocytes after sensibilisation with mitomycin C revealed chromosomal instability aspects. Based on these clinical and biological features, the diagnosis of hereditary aplastic anaemia was retained. The patient was given norethandrolone. She died 3 months later by septic shock. DISCUSSION: Coexistence of aplastic anemia with a malformative syndrome suggests most probably an hereditary form of aplastic anemia. Fanconi anemia is the most frequent. It associates characteristic anomalies of the face, with microphtalmia, brownish spots, statural and ponderal retardation, and thumb anomalies. Ungueal dystrophy, mucosal leucoplasia are almost pathognomonic of congenital dyskeratosis. When the malformative syndrome is not characteristic, the cytogenetic study may also fail to make the differential diagnosis, as was the situation in our case.


Assuntos
Anemia Aplástica/diagnóstico , Disceratose Congênita/complicações , Síndrome de Fanconi/complicações , Adulto , Anemia Aplástica/complicações , Anemia Aplástica/genética , Consanguinidade , Feminino , Humanos
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