8,384 research outputs found
The Scattering Approach to the Casimir Force
We present the scattering approach which is nowadays the best tool for
describing the Casimir force in realistic experimental configurations. After
reminders on the simple geometries of 1d space and specular scatterers in 3d
space, we discuss the case of stationary arbitrarily shaped mirrors in
electromagnetic vacuum. We then review specific calculations based on the
scattering approach, dealing for example with the forces or torques between
nanostructured surfaces and with the force between a plane and a sphere. In
these various cases, we account for the material dependence of the forces, and
show that the geometry dependence goes beyond the trivial {\it Proximity Force
Approximation} often used for discussing experiments.Comment: Proceedings of the QFEXT'09 conference (Oklahoma, 2009
Label-free detection of anticancer drug paclitaxel in living cells by confocal Raman microscopy
Confocal Raman microscopy, a non-invasive, label-free, and high spatial resolution imaging technique is employed to trace the anticancer drug paclitaxel in living Michigan Cancer Foundation-7 (MCF-7) cells. The Raman images were treated by K-mean cluster analysis to detect the drug in cells. Distribution of paclitaxel in cells is verified by calculating the correlation coefficient between the reference spectrum of the drug and the whole Raman image spectra. A time dependent gradual diffusion of paclitaxel all over the cell is observed suggesting a complementary picture of the pharmaceutical action of this drug based on rapid binding of free tubulin to crystallized paclitaxel. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4794871
Thermal Casimir Effect in the Plane-Sphere Geometry
The thermal Casimir force between two metallic plates is known to depend on
the description of material properties. For large separations the dissipative
Drude model leads to a force a factor of 2 smaller than the lossless plasma
model. Here we show that the plane-sphere geometry, in which current experiment
are performed, decreases this ratio to a factor of 3/2, as revealed by exact
numerical and large distance analytical calculations. For perfect reflectors,
we find a repulsive contribution of thermal photons to the force and negative
entropy values at intermediate distances.Comment: 4 pages, 3 figure
Recommended from our members
Potential of Balloon Photogrammetry for Spatially Continuous Snow Depth Measurements
Traumatic Obturator Hip Dislocation with Marginal Femoral Head Fracture in a 15-Year-Old Adolescent: A High-Energy Trauma-A Case Report and a Review of the Literature.
We report the case of a 15-year-old boy brought to the emergency department after a bike accident, complaining of an isolated left hip pain. The X-rays showed an obturator hip dislocation treated by closed reduction under general anaesthesia, followed by 6 weeks of discharge. The follow-up MRI performed 6 weeks after the trauma showed an avascular femoral head necrosis, for which we performed multiple retrograde femoral head drilling, completed by the injection of autologue stem cells from the iliaq crest. One year later, the patient has no hip pain, no joint limitation, and can practice BMX at a high level again. The purpose of this report is to make the physicians aware of this rare problem that may be damaging for hip function, especially in young people
Casimir interaction between plane and spherical metallic surfaces
We give an exact series expansion of the Casimir force between plane and
spherical metallic surfaces in the non trivial situation where the sphere
radius , the plane-sphere distance and the plasma wavelength
have arbitrary relative values. We then present numerical
evaluation of this expansion for not too small values of . For metallic
nanospheres where and have comparable values, we interpret
our results in terms of a correlation between the effects of geometry beyond
the proximity force approximation (PFA) and of finite reflectivity due to
material properties. We also discuss the interest of our results for the
current Casimir experiments performed with spheres of large radius .Comment: 4 pages, new presentation (highlighting the novelty of the results)
and added references. To appear in Physical Review Letter
Surface induced selective delamination of amphiphilic ABA block copolymer thin films
This is the result of an ongoing collaboration with Dr. N. Sommerdijk’s Biomaterials group at the University of Eindhoven (the Netherlands) and illustrates the close collaboration that exists in pursuing the design and application of novel polymeric materials between the two groups. This details work on a physical phenomenon (selective delamination) and key materials (amphiphilic block copolymers) that have subsequently been applied in the design of novel biomaterials. These results have appeared in a larger body of work including Advanced Materials, Angewandtie Chemie International Edition and the Journal of Materials Chemistry
Statistical Origin of Pseudo-Hermitian Supersymmetry and Pseudo-Hermitian Fermions
We show that the metric operator for a pseudo-supersymmetric Hamiltonian that
has at least one negative real eigenvalue is necessarily indefinite. We
introduce pseudo-Hermitian fermion (phermion) and abnormal phermion algebras
and provide a pair of basic realizations of the algebra of N=2
pseudo-supersymmetric quantum mechanics in which pseudo-supersymmetry is
identified with either a boson-phermion or a boson-abnormal-phermion exchange
symmetry. We further establish the physical equivalence (non-equivalence) of
phermions (abnormal phermions) with ordinary fermions, describe the underlying
Lie algebras, and study multi-particle systems of abnormal phermions. The
latter provides a certain bosonization of multi-fermion systems.Comment: 20 pages, to appear in J.Phys.
Diffractive Dissociation and Eikonalization in High Energy pp and p Collisions
We show that eikonal corrections imposed on diffraction dissociation
processes calculated in the triple Regge limit, produce a radical change in the
energy dependence of the predicted cross section. The induced correction is
shown to be in general agreement with the new experimental data measured at the
Tevatron.Comment: 11 pages LATEX, ( two figures not included obtainable from authors)
(TAUP 2066-93 and FERMILAB PUB 93/ T
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