87,637 research outputs found
Revelation of double magicity in N=Z nuclei in the rp-process region
In rapid-proton capture (rp-process), N=Z nuclei above Ni are understood to
act as waiting-point nuclei. The N=Z nuclei 68Se, 72Kr, 76Sr and 80Zr among
others are known to give rise to a large-energy x-ray flux and peaks in
abundances of these nuclei synthesized in the astrophysical rp-process.
Investigating the experimental isotope shifts in Kr isotopes near the proton
drip-line within the framework of the deformed Relativistic Hartree-Bogoliubov
theory, we have discovered that N=Z rp-process nuclei 68Se, 72Kr, 76Sr and 80Zr
exhibit large shell gap both at the proton and neutron numbers in the deformed
space with the consequence that pairing correlations for protons and neutrons
vanish. This lends a doubly magic character to these nuclei. A significant
number of nuclei in this region are also shown to exhibit neutron magicity at
N=34, 36, 38, and 40 in the deformed space. A unique case of concomitance of
the double magicity and the shape-coexistence is found for 68Se.Comment: 10 pages, 4 figures; Invited contribution presented at the
International Symposium on Exotic Nuclei, EXON 2009, Sochi, Russia, Sept.
28-Oct. 2, 200
Emerging Trends of Nanotechnology towards Picotechnology: Energy and Biomolecules
In nature, metal oxide particles display their existence at the level of picomolecules in solution state and bioactive states in the body. We present evidence of picomolar behavior of molecules different than nanomolar behavior of particles. These particles can be encapsulated in polymers and can be functionalized with protein, nucleotides, and drugs to develop as smart intracellular targeting pico-devices. The preparation technique and physiological conditions decide the size and functionality of these pico-carrier devices. Their usable success rate, feasibility and potentials are yet to be proven or we do not know. The major difference between nanodevices and pico-devices is their intermolecular and intramolecular thermodynamics in medium and their molecular conformational interaction with molecular assembly in cytoarchitecture of the neurofilament, actin-myosin, microtubule proteins. Pico-carrier devices can be presumed as potential spears without interacting with host signal transduction and immunoprotection. In conclusion, the ultrafine size of newer picotechnology products may be better suited and easier to functionalize for design of particle based picodrugs, picochemicals, and pico-targeting molecules
Primary Leiomyosarcoma of Ovary
Primary ovarian leiomyosarcomas is a rare neoplasm which comprises less than 3% of ovarian tumors. Their origin, etiology, histologic features, clinical behavior, and optimal treatment are still obscure. We report a case of leiomyosarcoma of ovary, diagnosed on histopathology in a 60 year old female and discuss the literature
Reply on `comment on our paper `Single two-level ion in an anharmonic-oscillator trap: Time evolution of the Q function and population inversion ''
We show here that the model Hamiltonian used in our paper for ion vibrating
in a q-analog harmonic oscillator trap and interacting with a classical
single-mode light field is indeed obtained by replacing the usual bosonic
creation and annihilation operators of the harmonic trap model by their
q-deformed counterparts. The approximations made in our paper amount to using
for the ion-laser interaction in a q-analog harmonic oscillator trap, the
operator F_{q}=exp{-(|\epsilon|^2}/2)}exp{i\epsilon A^{\dagger}}exp{i\epsilon
A}, which is analogous to the corresponding operator for ion in a harmonic
oscillator trap that is . In our article we do not claim to have diagonalized the
operator, , for which the basis states
|g,m> and |e,m> are not analytic vectors.Comment: Revtex, 4pages. To be Published in Physical Review A59, NO.4(April
99
- …