107 research outputs found
Endolymphatic sac tumour
We present a case of a papillary tumour at the cerebellopontine angle in a 41-year-old man. He presented with left-sided facial and ear pain associated with dizziness, nystagmus and hearing loss. CT scan of the temporal bone showed a destructive tumour at the left cerebellopontine angle. Surgical excision was performed and the diagnosis of the endolymphatic sac tumour was made. Endolymphatic tumour is a low grade adenocarcinoma that originates from the endolymphatic sac. The defi nitive diagnosis requires a combination of clinical features, radiological finding and pathological correlation
Optical Properties of ZnP2 Nanoparticles in Zeolite
We report that for the first time the nanoparticles of II-V semiconductor
(ZnP2) were prepared and studied. ZnP2 nanoparticles were prepared by
incorporation into zeolite Na-X matrix. Absorption, diffuse reflection (DR) and
photoluminescence (PL) spectra of the ZnP2 nanoclusters incorporated into the
supercages of zeolite Na-X were measured at the temperature 77 K. Five bands
B1-B5 are observed in both the DR and PL spectra demonstrating the blue shift
from the line of free exciton in bulk crystal. We attribute the B1-B5 bands to
some stable nanoclusters with size less than the size of zeolite Na-X
supercage. We observed Stokes shift of the PL bands from the respective
absorption bands. The nonmonotonic character of its dependence on the cluster
size can be explained as the result of competition of the Frank-Condon shift
and the shift due to electronic relaxation.Comment: Submitted to Microporous and Mesoporous Material
Juvenile nasopharyngeal angiofibroma in a tertiary centre_ ten-year experience
This is a retrospective study that aimed to examine the outcomes of patients presenting with juvenile nasopharyngeal angiofibroma (JNA) at a tertiary centre in Malaysia
Velopharyngeal stenosis, a late complication of radiotherapy
Choanal stenosis has recently been recognized as a late complication of radiation therapy for nasopharyngeal carcinoma. The management of velopharyngeal stenosis is challenging with high risk of restenosis. We report a case of velopharyngeal stenosis post-radiotherapy and illustrated the use of mitomycin-C to prevent restenosis. Mitomycin-C application has being shown useful adjunct to surgical technique in managing nasopharyngeal stenosis for surgeons
Migrating foreign body into the common carotid artery and internal jugular vein
Ingested foreign bodies are a fairly common otorhinolaryngological emergencies encountered in Malaysia. The vast majority of these foreign bodies are fish bones which most commonly are impacted at the level of the cricopharynx. Rarely, however, a foreign body may migrate extraluminally and may even extrude subcutaneously. We report a rare occurrence where a fish bone not only migrated extraluminally, it was found to have migrated into the common carotid artery and the internal jugular vein and required surgical removal
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
How well do we understand the reaction rate of C burning?
Carbon burning plays a crucial role in stellar evolution, where this reaction is an important route for the production of heavier elements. A particle-Îł coincidence technique that minimizes the backgrounds to which this reaction is subject and provides reliable cross sections has been used at the Argonne National Laboratory to measure fusion cross-sections at deep sub-barrier energies in the 12C+12C system. The corresponding excitation function has been extracted down to a cross section of about 6 nb. This indicates the existence of a broad S-factor maximum for this system. Experimental results are presented and discussed
Dilaton Dark Energy Model in f(R), f(T) and Horava-Lifshitz Gravities
In this work, we have considered dilaton dark energy model in Weyl-scaled
induced gravitational theory in presence of barotropic fluid. It is to be noted
that the dilaton field behaves as a quintessence. Here we have discussed the
role of dilaton dark energy in modified gravity theories namely, f(R); f(T) and
Horava-Lifshitz gravities and analyzed the behaviour of the dilaton field and
the corresponding potential in respect to these modified gravity theories
instead of Einstein's gravity. In f(R) and f(T) gravities, we have considered
some particular forms of f(R) and f(T) and we have shown that the potentials
always increase with the dilaton fields. But in Horava-Lifshitz gravity, it has
been seen that the potential always decreases as dilation field increases
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