1,799 research outputs found
Violation of the Ikeda sum rule and the self-consistency in the renormalized quasiparticle random phase approximation and the nuclear double-beta decay
The effect of the inclusion of ground state correlations into the QRPA
equation of motion for the two-neutrino double beta () decay
is carefully analyzed. The resulting model, called renormalized QRPA (RQRPA),
does not collapse near the physical value of the nuclear force strength in the
particle-particle channel, as happens with the ordinary QRPA. Still, the
transition amplitude is only slightly less sensitive on
this parameter in the RQRPA than that in the plain QRPA. It is argued that this
fact reveals once more that the characteristic behaviour of the
transition amplitude within the QRPA is not an artifact of
the model, but a consequence of the partial restoration of the spin-isospin
symmetry. It is shown that the price paid for bypassing the collapse in
the RQRPA is the violation of the Ikeda sum rule.Comment: 16 pages, latex, 3 postscript figure
The Noncommutative Anandan's Quantum Phase
In this work we study the noncommutative nonrelativistic quantum dynamics of
a neutral particle, that possesses permanent magnetic and electric dipole
momenta, in the presence of an electric and magnetic fields. We use the
Foldy-Wouthuysen transformation of the Dirac spinor with a non-minimal coupling
to obtain the nonrelativistic limit. In this limit, we will study the
noncommutative quantum dynamics and obtain the noncommutative Anandan's
geometric phase. We analyze the situation where magnetic dipole moment of the
particle is zero and we obtain the noncommutative version of the
He-McKellar-Wilkens effect. We demonstrate that this phase in the
noncommutative case is a geometric dispersive phase. We also investigate this
geometric phase considering the noncommutativity in the phase space and the
Anandan's phase is obtained.Comment: 15 pages, revtex4, version to appear in Physical Review
Systemic Treatment of Metastatic Conjunctival Melanoma.
Conjunctival melanoma (CM) is an exceptionally rare tumor, with a propensity for local and distant recurrence, with the lungs, skin, liver, and brain being the most common sites of metastasis. Recent progress in systemic treatments, with checkpoint inhibitors and targeted therapies blocking BRAF and MEK, has redefined the standard of care of advanced unresectable and metastatic melanoma. Although most trials did not include patients with conjunctival melanoma, its close molecular and genetic relationship to cutaneous melanoma might suggest a similar response to these novel agents. The authors describe two uncommon cases of metastatic conjunctival melanomas with distinct genetic profiles and, as such, submitted to different systemic treatments.info:eu-repo/semantics/publishedVersio
Surface tension driven flow of blood in a rectangular microfluidic channel: Effect of erythrocyte aggregation
Microfluidic platforms have increasingly been explored for in vitro blood diagnostics and for
studying complex microvascular processes. The perfusion of blood in such devices is typically achieved
through pressure driven set-ups. Surface tension driven blood flow provides an alternative flow delivery
option, and various studies in the literature have examined the behaviour of blood flow in such fluidic
devices. In such flows, the influence of red blood cell (RBC) aggregation, the phenomenon majorly
responsible for the non-Newtonian nature of blood, requires particular attention. In the present work, we
examine differences in the surface tension driven flow of aggregating, non-aggregating RBC, and
Newtonian suspensions, in a rectangular micro channel. The velocity fields were obtained using microPIV techniques. The analytical solution for blood velocity in the channel is developed utilising the power
law model for blood viscosity. The results showed that RBC aggregation has an impact at the late stages
of the flow, observed mainly in the bluntness of the velocity profiles. At the initial stages of the flow the
shearing conditions are found moderately elevated, preventing intense RBC aggregate formation. As the
flow decelerates in the channel RBC aggregation increases, affecting the flow characteristics
Manejo de plantas matrizes de porta-enxerto híbrido de citros.
A formação de sementes de citros depende diretamente da polinização, sendo que em alguns casos ocorre a autoincompatibilidade. Nesse trabalho, avaliaram-se práticas de manejo de plantas matrizes de novo porta-enxerto de citros visando maior produção e qualidade de sementes. O experimento iniciou em agosto de 2012 com as plantas matrizes instaladas na área experimental da Embrapa Mandioca e Fruticultura, em Cruz das Almas-BA
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