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Complete response of skull base inverted papilloma to chemotherapy: Case report.
BackgroundInverted papilloma (IP) is the most common benign sinonasal neoplasm. Endoscopic techniques, improved understanding of pathophysiology, and novel surgical approaches have allowed rhinologists to treat IPs more effectively, with surgery being the mainstay of therapy. Frontal sinus IP poses a challenge for surgical therapy due to complex anatomy and potentially difficult surgical access.ObjectivesWe reported a unique case of a massive frontal sinus IP that presented with intracranial and orbital extension, with near resolution after chemotherapy.MethodsA retrospective case review of a patient with a frontal sinus IP treated at a tertiary academic medical center.ResultsA 75-year-old male patient presented with nasal obstruction, purulent nasal discharge, and a growing left supraorbital mass. Endoscopy demonstrated a mass that filled both frontal and ethmoid sinuses, with orbital invasion. There also was substantial erosion of the posterior table, which measured 1.73 Ă— 1.40 cm. A biopsy specimen demonstrated IP with carcinoma in situ. The patient was deemed unresectable on initial evaluation and, subsequently, underwent chemotherapy (carboplatin and paclitaxel). The tumor had a dramatic response to chemotherapy, and the patient elected for definitive surgery to remove any residual disease. During surgery, only a small focus of IP was found along the superior wall of the frontal sinus. No tumor was found elsewhere, including at the site of skull base erosion. The final pathology was IP without carcinoma in situ or dysplasia.ConclusionThis was the first reported case of chemotherapeutic "debulking" of IP, which facilitated surgical resection, despite substantial intracranial and orbital involvement. Although nearly all IPs can be treated surgically, rare cases, such as unresectable tumors, may benefit from systemic chemotherapy
Gravitational Waves From the End of Inflation: Computational Strategies
Parametric resonance or preheating is a plausible mechanism for bringing
about the transition between the inflationary phase and a hot, radiation
dominated universe. This epoch results in the rapid production of heavy
particles far from thermal equilibrium and could source a significant
stochastic background of gravitational radiation. Here, we present a numerical
algorithm for computing the contemporary power spectrum of gravity waves
generated in this post-inflationary phase transition for a large class of
scalar-field driven inflationary models. We explicitly calculate this spectrum
for both quartic and quadratic models of chaotic inflation, and low-scale
hybrid models. In particular, we consider hybrid models with an ``inverted''
potential. These models have a very short and intense period of resonance which
is qualitatively different from previous examples studied in this context, but
we find that they lead to a similar spectrum of gravitational radiation.Comment: 15 pages, 13 figure
A preliminary design tool for volumetric buildings
Volumetric building (VB) is a type of off-site construction to move towards high productivity construction. Literature review shows that there are only few models for upstream feasibility study for VB, while many researchers delved into advanced structural engineering aspects of VB modeling (i.e., downstream detailed and technical design). However, there is a lack of guidance for the preliminary design of VB, which is an essential stage that falls in between upstream feasibility study and downstream detailed and technical design. Hence, this paper is written to fill that gap by proposing a new design tool for VB, anchored upon the “desire path” philosophy, which is often used in urban planning, that is, natural formations evident from preceding experiences. Literature review also shows that a comprehensive VB database is not available. Hence, a new database is collected with 31,185 units of modules and 911 module types, sourced from VB projects worldwide to provide a broad global overview. The proposed tool has a systematic framework of a four-quadrant plot for preliminary VB design, enabling designers to determine the number of modules, size of modules, massing typology, and module construction material through new empirical relationships.</p
Asymptotic silence-breaking singularities
We discuss three complementary aspects of scalar curvature singularities:
asymptotic causal properties, asymptotic Ricci and Weyl curvature, and
asymptotic spatial properties. We divide scalar curvature singularities into
two classes: so-called asymptotically silent singularities and non-generic
singularities that break asymptotic silence. The emphasis in this paper is on
the latter class which have not been previously discussed. We illustrate the
above aspects and concepts by describing the singularities of a number of
representative explicit perfect fluid solutions.Comment: 25 pages, 6 figure
Speech Processing Research Program
Contains an introduction and reports on five research projects.National Science Foundation Grant MIP 87-14969National Science Foundation FellowshipU.S. Air Force - Electronic Systems Division Contract F1 9628-89-K-0041U.S. Navy - Office of Naval Research Contract N00014-89-J-148
Germline Mutation in NLRP2 (NALP2) in a Familial Imprinting Disorder (Beckwith-Wiedemann Syndrome)
Beckwith-Wiedemann syndrome (BWS) is a fetal overgrowth and human imprinting disorder resulting from the deregulation of a number of genes, including IGF2 and CDKN1C, in the imprinted gene cluster on chromosome 11p15.5. Most cases are sporadic and result from epimutations at either of the two 11p15.5 imprinting centres (IC1 and IC2). However, rare familial cases may be associated with germline 11p15.5 deletions causing abnormal imprinting in cis. We report a family with BWS and an IC2 epimutation in which affected siblings had inherited different parental 11p15.5 alleles excluding an in cis mechanism. Using a positional-candidate gene approach, we found that the mother was homozygous for a frameshift mutation in exon 6 of NLRP2. While germline mutations in NLRP7 have previously been associated with familial hydatidiform mole, this is the first description of NLRP2 mutation in human disease and the first report of a trans mechanism for disordered imprinting in BWS. These observations are consistent with the hypothesis that NLRP2 has a previously unrecognised role in establishing or maintaining genomic imprinting in humans
Terahertz study of trichloroanisole by time-domain spectroscopy,”
a b s t r a c t The THz transmission spectra of three trichloroanisole (TCA) compounds (2,3,4-TCA, 2,4,6-TCA and 2,5,6-TCA) are measured using terahertz time-domain spectroscopy (THz-TDS). The spectrum of 2,4,6-TCA in the solid phase displays several discrete absorption peaks over frequency range from 0.1 to 1.5 THz, with significant peaks observed at 0.6, 0.95 and 1.2 THz. A weak absorption peak is observed near 0.2-0.3 THz. Computational chemistry using the B3LYP density functional method is used to study structure and internal rotations in 2,4,6-TCA, where results strongly suggest that frequencies of the CH 3 O-carbon(benzene) internal rotor of the methoxy group correspond to the observed spectra
Suitability for salt-lick tourism: A preliminary assessment on the natural saltlicks at Segaliud-Lokan Forest Reserve, Sandakan, Sabah
The natural salt-licks are visited by various species of terrestrial mammals, hence ideal for mammal watching, although the suitability for salt-lick tourism is influenced by other factors. Preliminary research was conducted on the suitability of four natural salt-licks for mammal watching in Segaliud-Lokan Forest Reserve (SLFR), Sabah. The camera trapping survey and field assessment were conducted for eight months, and then the assessment criteria applied in this study included the lick accessibility, detection frequency, species richness, viewable activity sighting probability, reliability and visibility on the terrestrial mammals, at a given lick. A total of 12 different mammal species were recorded, where Sambar Deer, Bearded Pig, Banteng, and Bornean Orang-utan were determined as the main visitor species of this study. Among the four selected salt-licks, the rating score of SL50A (Score=1.71) was significantly lower than those of SL50B, SL56 and SL59 (Score=2.57 respectively, χ2 2=6.794, p=0.042), hence highlighting that SL50A was not suitable for conducting mammal watching activity, unlike the other three natural licks at SLFR. The assessment on the compatibility between the supply (mammalian physical availability) and demand (highly anticipated species) was excluded from this research, therefore emphasizing the need to fill up this particular research gap in the future
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