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Papillary cystadenoma of the parotid gland: A case report.
BackgroundPapillary cystadenoma is a rare benign epithelial tumor of the salivary gland, which is characterized by papillary structures and oncocytic cells with rich eosinophilic cytoplasm. We found only one case of papillary cystadenoma in nearly 700 cases of salivary gland tumors. Our case was initially mistaken for a tumor of the right temporomandibular joint (TMJ) capsule rather than of parotid gland origin. Preoperative magnetic resonance imaging (MRI) and computed tomography (CT) should be carefully studied, which allows for appropriate preoperative counseling and operative planning.Case summaryHere, we report an unusual case of a 54-year-old woman with a parotid gland papillary cystadenoma (PGPC) that was misdiagnosed as a tumor of the right TMJ capsule. She was initially admitted to our hospital due to a mass anterior to her right ear inadvertently found 5 d ago. Preoperative CT and MRI revealed a well circumscribed tumor that was attached to the right TMJ capsule. The patient underwent a resection through an incision for TMJ, but evaluation of an intraoperative frozen section revealed a benign tumor of the parotid gland. Then we removed part of the parotid gland above the temporal facial trunk. The facial nerve was preserved. Postoperative histopathological findings revealed that the tumor was PGPC. No additional treatment was performed. There was no recurrence during a 20-mo follow-up period.ConclusionThe integrity of the interstitial space around the condyle in MRI or CT should be carefully evaluated for parotid gland or TMJ tumors
Slow cross-symmetry phase relaxation in complex collisions
We discuss the effect of slow phase relaxation and the spin off-diagonal
-matrix correlations on the cross section energy oscillations and the time
evolution of the highly excited intermediate systems formed in complex
collisions. Such deformed intermediate complexes with strongly overlapping
resonances can be formed in heavy ion collisions, bimolecular chemical
reactions and atomic cluster collisions. The effects of quasiperiodic energy
dependence of the cross sections, coherent rotation of the hyperdeformed
intermediate complex, Schr\"odinger cat states and
quantum-classical transition are studied for Mg+Si heavy ion
scattering.Comment: 10 pages including 2 color ps figures. To be published in Physics of
Atomic Nuclei (Yadernaya fizika
Si-based anode materials for lithium rechargeable batteries
Silicon is a very promising candidate to replace graphite as the anode in Li-ion batteries because of its very high theoretical capacity, relatively low cost and low toxicity. However, it has not yet made its way into commercial cells. This review highlights recent progress on Si-based anode materials for lithium rechargeable batteries
Atomic oxygen adsorption and incipient oxidation of the Pb(111) surface: A density-functional theory study
We study the atomic oxygen adsorption on Pb(111) surface by using
density-functional theory within the generalized gradient approximation and a
supercell approach. The atomic and energetic properties of purely on-surface
and subsurface oxygen structures at the Pb(111) surface are systematically
investigated for a wide range of coverages and adsorption sites. The fcc and
tetra-II sites (see the text for definition) are found to be energetically
preferred for the on-surface and subsurface adsorption, respectively, in the
whole range of coverage considered. The on-surface and subsurface oxygen
binding energies monotonically increase with the coverage, and the latter is
always higher than the former, thus indicating the tendency to the formation of
oxygen islands (clusters) and the higher stability of subsurface adsorption.
The on-surface and subsurface diffusion-path energetics of atomic oxygen, and
the activation barriers for the O penetration from the on-surface to the
subsurface sites are presented at low and high coverages. In particular, it is
shown that the penetration barrier from the on-surface hcp to the subsurface
tetra-I site is as small as 65 meV at low coverage (=0.25). The other
properties of the O/Pb(111) system, including the charge distribution, the
lattice relaxation, the work function, and the electronic density of states,
are also studied and discussed in detail, which consistently show the gradually
stabilizing ionic O-Pb bond with increase of the oxygen coverage.Comment: 31 pages, 16 figure
Boundary K-matrices and the Lax pair for 1D open XYZ spin-chain
We analysis the symmetries of the reflection equation for open model
and find their solutions case by case. In the general open boundary
conditions, the Lax pair for open one-dimensional spin-chain is given.Comment: LaTeX, 17 pages, errors in references correcte
Synthesis of silicalite-poly(furfuryl alcohol) composite membranes for oxygen enrichment from air
Silicalite-poly(furfuryl alcohol) [PFA] composite membranes were prepared by solution casting of silicalite-furfuryl alcohol [FA] suspension on a porous polysulfone substrate and subsequent in situ polymerization of FA. X-ray diffraction, nitrogen sorption, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were used to characterize silicalite nanocrystals and silicalite-PFA composite membranes. The silicalite-PFA composite membrane with 20 wt.% silicalite loading exhibits good oxygen/nitrogen selectivity (4.15) and high oxygen permeability (1,132.6 Barrers) at 50°C. Silicalite-PFA composite membranes are promising for the production of oxygen-enriched air for various applications
Cellular Assays for High-Throughput Screening for Modulators of Trk Receptor Tyrosine Kinases
Trk receptor tyrosine kinases are required for signal transduction initiated by neurotrophins leading to cell proliferation, differentiation, survival and death. Alterations in Trk kinase activity have been linked to various diseases. To address the need for cell-based assays for screening and studying the selectivity of Trk kinase modulators, we developed high-throughput cell-based assays for Trk receptor kinases using nuclear factor of activated T-cells (NFAT) beta-lactamase reporter lines stably expressing full length human Trk kinases. These assays were functionally validated with cognate neurotrophin(s), inhibitors and TRK RNAi oligos and demonstrated for their utility in identifying potent and selective modulators of Trk receptor kinases
A simple Fourier transform-based reconstruction formula for photoacoustic computed tomography with a circular or spherical measurement geometry
Photoacoustic computed tomography (PACT), also known as optoacoustic
tomography, is an emerging imaging modality that has great potential for a wide
range of biomedical imaging applications. In this Note, we derive a hybrid
reconstruction formula that is mathematically exact and operates on a data
function that is expressed in the temporal frequency and spatial domains. This
formula explicitly reveals new insights into how the spatial frequency
components of the sought-after object function are determined by the temporal
frequency components of the data function measured with a circular or spherical
measurement geometry in two- and three-dimensional implementations of PACT,
respectively. The structure of the reconstruction formula is surprisingly
simple compared with existing Fourier-domain reconstruction formulae. It also
yields a straightforward numerical implementation that is robust and two orders
of magnitude more computationally efficient than filtered backprojection
algorithms.Comment: http://iopscience.iop.org/0031-9155/57/23/N493
Preparation and characterization of core/shell-like intumescent flame retardant and its application in Polypropylene
With a shell of starch-melamine-formaldehyde (SMF) resin, core/shell-like ammonium polyphosphate (SMFAPP) is prepared by in situ polymerization, and is characterized by SEM, FTIR and XPS. The shell leads SMFAPP a high water resistance and flame retardance compared with APP in polypropylene (PP). The flame retardant action of SMFAPP and APP in PP are studied using LOI, UL 94 test and cone calorimeter, and their thermal stability is evaluated by TG. The flame retardancy and water resistance of the PP/SMFAPP composite at the same loading is better than that of the PP/APP composite. UL 94 ratings of PP/SMFAPP can reach V-0 at 30 wt% loading. The flame retardant mechanism of SMFAPP was studied by dynamic FTIR, TG and cone calorimeter, etc
The 6-vertex model of hydrogen-bonded crystals with bond defects
It is shown that the percolation model of hydrogen-bonded crystals, which is
a 6-vertex model with bond defects, is completely equivalent with an 8-vertex
model in an external electric field. Using this equivalence we solve exactly a
particular 6-vertex model with bond defects. The general solution for the
Bethe-like lattice is also analyzed.Comment: 13 pages, 6 figures; added references for section
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