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1.
Artigo em Inglês | MEDLINE | ID: mdl-39172484

RESUMO

This cohort study evaluates whether in-office biopsies significantly improve time to biopsy and time to treatment compared with operating room biopsies.

2.
Opt Lett ; 48(15): 3925-3928, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527084

RESUMO

Plasmonic filters based on subwavelength nanohole arrays are an attractive solution for creating arrays of filters with varying passbands in a single lithography step. In this work, we have developed a fabrication method which allows fabrication of nanohole arrays in silver by use of a thin layer of aluminum oxide, which serves the dual purpose of both capping layer and hardmask for metal patterning. We demonstrate arrays of gold and silver mid-infrared plasmonic filters, fabricated on silicon, intended for use in optical filter blocks or for future integration with infrared imagers. The filter arrays are designed for the wavelength range 2-7 µm, and exhibit peak filter transmission efficiencies around 70%.

3.
Ann Otol Rhinol Laryngol ; 132(8): 873-878, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35983610

RESUMO

BACKGROUND AND OBJECTIVES: Performing an effective maxillary antrostomy is critical to improving chronic maxillary sinusitis symptomatology. Incomplete dissection of the uncinate process and failure to incorporate the natural drainage pathway may lead to recirculation and need for revision surgery. The purpose of this study is to determine if 70° endoscopes provide added value in determining incomplete dissection or residual disease. METHODS: Prospective study of 35 sinuses from 18 patients undergoing FESS for Chronic Rhinosinusitis (CRS) between 11/1/2020 and 4/30/2021. Two fellowship trained Rhinologists initially performed maxillary antrostomies exclusively using a 0° endoscope, then transitioned to a 70° endoscope. Surgeons completed a survey to assess completion of the antrostomy prior to use of 70° endoscope, sino-nasal anatomy, and difficulty of the operation. Intraoperative photographs before and after using a 70° endoscope were evaluated by a third party. Pre-operative CT scans were used to evaluate the sphenoid keel-caudal septum-nasolacrimal duct (SK-CS-NL) angle. RESULTS: Of 35 sinuses from 18 patients all 35 sinuses had CRS with 48.5% having nasal polyposis and 42.9% having active infection. There was residual inflammatory tissue in the anterior maxillary sinus, including polypoid tissue and uncinate process prior to using the 70° endoscope in 82.9% of sinuses. The natural drainage pathway was not incorporated into the dissection in 28.6% of sinuses before converting to 70° endoscope. Incomplete dissection with 0° endoscope was not associated with nasal polyposis (P = .086) or uncinate position (0.741). Narrow SK-CS-NL angles were associated with incomplete dissection of the anterior maxillary sinus with 0° endoscope (16.0° ± 3.0° vs 20.6° ± 3.2°; P = .013). CONCLUSION: Use of 70° endoscope in maxillary antrostomy may be beneficial in identifying and resecting disease within the anterior maxillary sinus that may otherwise be difficult to find using a 0° endoscope. This is especially true in patients with narrow nasolacrimal duct positioning.


Assuntos
Sinusite Maxilar , Pólipos Nasais , Sinusite , Humanos , Endoscopia , Estudos Prospectivos , Sinusite/cirurgia , Seio Maxilar/cirurgia , Seio Maxilar/anatomia & histologia , Sinusite Maxilar/cirurgia , Doença Crônica
4.
Laryngoscope Investig Otolaryngol ; 7(4): 988-993, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36000056

RESUMO

Background: The incidence of p16+ oropharyngeal squamous cell carcinoma (OPSCC) has been increasing. The notion that p16+ OPSCC has a propensity for atypical and disseminating metastasis has gained traction. We compared treatment failure patterns in p16+ and p16- OPSCC and evaluated survival impact. Methods: Retrospective analysis of patients with recurrent/metastatic OPSCC disease between 1/2009 and 12/2019. Results: Thirty-eight p16+ and 36 p16- patients were identified. Three distinct failure patterns (distant vs. locoregional, atypical vs. typical, and disseminating vs. non-disseminating) were studied. No significant differences were found between p16+ and p16- patients. Multivariate analysis showed p16 status was an independent prognostic biomarker; p16+ patients have a favorable overall survival compared to p16- patients (HR 0.34, 95% CI 0.16-0.77; P = .005). Conclusions: We challenge the view that p16+ OPSCC exhibits a distinctive treatment failure pattern and showed that p16 status impacts patient survival independent of disease progression.

5.
Adv Sci (Weinh) ; 9(27): e2201227, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35821385

RESUMO

A broadband, high efficiency polarized beam splitter (PBS) metagrating based on integrated resonant units (IRUs) to enable simultaneous polarization analysis, spectral dispersion, and spatial imaging in the near infrared (NIR) is developed. A PBS metagrating with a diameter of 60 mm is the key technology component of the high-resolution multiple-species atmospheric profiler in the NIR (HiMAP-NIR), which is a spaceborne instrument concept crafted to be a core payload of NASA's new generation Earth System Observatory. HiMAP-NIR will enable the aerosol profiling in Earth's planetary boundary layer (from surface to2 km altitude) by simultaneously measuring four spatial-spectral-polarimetric images from 680 to 780 nm. Through detailed optimization of hybridized resonant modes in IRUs, the PBS metagrating shows a diffraction efficiency of 70% (or better) for all four linear-polarized incident light, and polarization contrasts between orthogonal states are 0.996 (or better) from 680 to 780 nm. It meets the stringent performance required by the HiMAP-NIR exploiting a new paradigm for the broad applications of metasurfaces.

6.
Head Neck ; 44(5): 1164-1171, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35212072

RESUMO

BACKGROUND: Synchronous primary tumors (SPTs) are detected via triple endoscopy or positron emission tomography/computed tomography (PET/CT). Patients with human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV+ OPSCC) lack risk factors for SPTs. METHODS: We performed a single institution retrospective review of the efficacy of triple endoscopy and PET/CT in HPV+ OPSCC patients. RESULTS: Sixty-five HPV+ OPSCC patients underwent triple endoscopy and PET/CT. Patients were white (n = 48, 72.7%), male (n = 53, 81.5%), mean 58.7 ± 8.1 years old. SPT was detected in 1 (1.5%) patient via PET/CT. No SPTs were detected on triple endoscopy. PET/CT had 100% and 95.3% sensitivity and specificity, respectively. PET/CT positive predictive value (PPV) and negative predictive value (NPV) were 25.0% and 100%, respectively. Triple endoscopy specificity and NPV was 90.2% and 93.2%, respectively. CONCLUSIONS: PET/CT is superior to triple endoscopy in ruling out SPTs. With negative PET/CT, only direct laryngoscopy with biopsy may be necessary.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Idoso , Carcinoma de Células Escamosas/patologia , Endoscopia , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/patologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem
7.
Opt Express ; 27(13): 17561-17570, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31252713

RESUMO

We report on 4x20 silicon photonic MEMS switch that is capable of multicasting. The switch is built on passive optical crossbar network with gap-adjustable directional couplers. The switch has high on-off extinction ratio (59 dB), low insertion loss (< 4.0 dB), small footprint (1.2x4.5 mm2), and fast response (9.8 µs). The switching voltage is 9.6 V and 20 dB bandwidth is 31.5 nm. One-to-two and one-to-four multicast operations are demonstrated.

8.
PLoS One ; 10(8): e0135749, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26291610

RESUMO

China has recently made available hourly air pollution data from over 1500 sites, including airborne particulate matter (PM), SO2, NO2, and O3. We apply Kriging interpolation to four months of data to derive pollution maps for eastern China. Consistent with prior findings, the greatest pollution occurs in the east, but significant levels are widespread across northern and central China and are not limited to major cities or geologic basins. Sources of pollution are widespread, but are particularly intense in a northeast corridor that extends from near Shanghai to north of Beijing. During our analysis period, 92% of the population of China experienced >120 hours of unhealthy air (US EPA standard), and 38% experienced average concentrations that were unhealthy. China's population-weighted average exposure to PM2.5 was 52 µg/m3. The observed air pollution is calculated to contribute to 1.6 million deaths/year in China [0.7-2.2 million deaths/year at 95% confidence], roughly 17% of all deaths in China.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Material Particulado/análise , China , Cidades , Dióxido de Nitrogênio/análise , Ozônio/análise , Dióxido de Enxofre/análise , Fatores de Tempo
9.
ACS Nano ; 9(8): 7738-41, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26197037

RESUMO

Quantum simulations promise to be one of the primary applications of quantum computers, should one be constructed. This article briefly summarizes the history of quantum simulation in light of the recent result of Wang and co-workers, demonstrating calculation of the ground and excited states for a HeH(+) molecule, and concludes with a discussion of why this and other recent progress in the field suggest that quantum simulations of quantum chemistry have a bright future.

10.
Nano Lett ; 13(12): 5785-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24199677

RESUMO

We report Pauli blockade in a multielectron silicon metal-oxide-semiconductor double quantum dot with an integrated charge sensor. The current is rectified up to a blockade energy of 0.18 ± 0.03 meV. The blockade energy is analogous to singlet-triplet splitting in a two electron double quantum dot. Built-in imbalances of tunnel rates in the MOS DQD obfuscate some edges of the bias triangles. A method to extract the bias triangles is described, and a numeric rate-equation simulation is used to understand the effect of tunneling imbalances and finite temperature on charge stability (honeycomb) diagram, in particular the identification of missing and shifting edges. A bound on relaxation time of the triplet-like state is also obtained from this measurement.


Assuntos
Metais/química , Nanotecnologia , Óxidos/química , Pontos Quânticos/química , Semicondutores
12.
Nano Lett ; 10(8): 2749-54, 2010 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-20698586

RESUMO

We demonstrate a method for fabricating arrays of plasmonic nanoparticles with separations on the order of 1 nm using an angle evaporation technique. Samples fabricated on thin SiN membranes are imaged with high-resolution transmission electron microscopy (HRTEM) to resolve the small separations achieved between nanoparticles. When irradiated with laser light, these nearly touching metal nanoparticles produce extremely high electric field intensities, which result in surface-enhanced Raman spectroscopy (SERS) signals. We quantify these enhancements by depositing a p-aminothiophenol dye molecule on the nanoparticle arrays and spatially mapping their Raman intensities using confocal micro-Raman spectroscopy. Our results show significant enhancement when the incident laser is polarized parallel to the axis of the nanoparticle pairs, whereas no enhancement is observed for the perpendicular polarization. These results demonstrate proof-of-principle of this fabrication technique. Finite difference time domain simulations based on HRTEM images predict an electric field intensity enhancement of 82400 at the center of the nanoparticle pair and an electromagnetic SERS enhancement factor of 10(9)-10(10).

13.
J Comput Chem ; 31(9): 1860-3, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20087901

RESUMO

We present results that compare the accuracy of the AM05 density functional (Armiento and Mattsson, Phys Rev B 2005, 72, 085108; Mattsson et al., J Chem Phys 2008, 128, 084714) to a set of chemical reaction energies. The reactions were generated from the singlet species in the well-known G2 test suite (Curtiss et al., J Chem Phys 1991; Curtiss et al., J Chem Phys 1997; 106, 1063). Our results show that, in general, the AM05 functional performs nearly as well as the other "pure" density functionals, but none of these perform as well as the hybrid B3LYP functional. These results are nonetheless encouraging because the AM05 functional arises from very simple assumptions, and does not require the calculation of the Hartree-Fock exchange integrals.

14.
J Am Chem Soc ; 131(4): 1346-7, 2009 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19173658

RESUMO

Hydrogenolysis reactions of palladium(II) hydroxide and methoxide complexes to form water and methanol, respectively, and the corresponding palladium(II) hydride are reported. In the presence of water, 1 was found to exist in solution as a water-bridged dimer; however, kinetic studies suggest the reaction of 1 and H(2) proceeds exclusively through the hydroxide monomer to form the palladium(II) hydride and water. Computational studies suggest a four-center intramolecular proton transfer as opposed to an oxidative addition/reductive elimination pathway.

16.
J Comput Chem ; 29(1): 8-16, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17918283

RESUMO

A manager-worker-based parallelization algorithm for Quantum Monte Carlo (QMC-MW) is presented and compared with the pure iterative parallelization algorithm, which is in common use. The new manager-worker algorithm performs automatic load balancing, allowing it to perform near the theoretical maximal speed even on heterogeneous parallel computers. Furthermore, the new algorithm performs as well as the pure iterative algorithm on homogeneous parallel computers. When combined with the dynamic distributable decorrelation algorithm (DDDA) [Feldmann et al., J Comput Chem 28, 2309 (2007)], the new manager-worker algorithm allows QMC calculations to be terminated at a prespecified level of convergence rather than upon a prespecified number of steps (the common practice). This allows a guaranteed level of precision at the least cost. Additionally, we show (by both analytic derivation and experimental verification) that standard QMC implementations are not "perfectly parallel" as is often claimed.


Assuntos
Modelos Estatísticos , Teoria Quântica , Algoritmos , Método de Monte Carlo
17.
J Comput Chem ; 28(14): 2309-16, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17476669

RESUMO

We describe the Dynamic Distributable Decorrelation Algorithm (DDDA) which efficiently calculates the true statistical error of an expectation value obtained from serially correlated data "on-the-fly," as the calculation progresses. DDDA is an improvement on the Flyvbjerg-Petersen renormalization group blocking method (Flyvberg and Peterson, J Chem Phys 1989, 91, 461). This "on-the-fly" determination of statistical quantities allows dynamic termination of Monte Carlo calculations once a specified level of convergence is attained. This is highly desirable when the required precision might take days or months to compute, but cannot be accurately estimated prior to the calculation. Furthermore, DDDA allows for a parallel implementation which requires very low communication, O(log(2)N), and can also evaluate the variance of a calculation efficiently "on-the-fly." Quantum Monte Carlo calculations are presented to illustrate "on-the-fly" variance calculations for serial and massively parallel Monte Carlo calculations.


Assuntos
Algoritmos , Interpretação Estatística de Dados , Modelos Estatísticos , Método de Monte Carlo , Triazinas/química
18.
Inorg Chem ; 45(24): 9631-3, 2006 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-17112254

RESUMO

The mechanism of the direct insertion of molecular oxygen into a palladium hydride bond has been elucidated using quantum mechanics (B3LYP/LACVP** with the PBF continuum solvent model). The key step is found to be the abstraction of the hydrogen atom resulting in the formation of a PdI/HO2 (triplet) radical pair, which then proceeds to form a singlet palladium hydroperoxo species. Potential palladium(0) pathways were explored and were found to be inaccessible. The results are in agreement with recent experimental results and are consistent with our previously predicted mechanism for an analogue system.

19.
J Chem Phys ; 125(5): 054101, 2006 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16942197

RESUMO

The optimized effective potential (OEP) method allows orbital-dependent functionals to be used in density functional theory. Traditionally the orbital-dependent functional of interest has been the Hartree-Fock energy, leading to exact exchange density functional theory. Here we present results that use a generalized valence-bond (GVB) wave function, a multiconfigurational wave function that includes static correlation and dissociates to the proper limits. We demonstrate the effectiveness of the OEP-GVB method by showing the dissociation of H2 and the excitation spectrum of He.

20.
Am J Surg Pathol ; 29(11): 1524-9, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16224221

RESUMO

Composite tumors of the stomach consisting of mixed glandular and endocrine components are rare. We report 3 cases of composite glandular and endocrine tumors with pancreatic acinar differentiation in the stomach with their clinicopathologic findings. The patients' presenting symptoms were variable and included abdominal pain, gastrointestinal hemorrhage, and weight loss. One patient with abdominal pain also had an elevated serum lipase level, clinically mimicking acute pancreatitis. The histology of these tumors was similar. They showed admixture of well-differentiated endocrine components with acinar and glandular components. The glandular component consisted of columnar epithelial cells resembling gastric foveolar or intestinal goblet cells, consistent with a well-differentiated adenocarcinoma. A panel of histochemical and immunohistochemical stains was performed, which included PAS, Alcian blue, Mib1, CEA, cytokeratin 7, cytokeratin 20, Muc2, Muc5AC, chromogranin, synaptophysin, trypsin, chymotrypsin, lipase, insulin, gastrin, serotonin, and pancreatic polypeptide. While the immunoreactivity for cytokeratin 7, cytokeratin 20, Muc2, Muc5AC, and CEA was largely restricted to the glandular component, the endocrine and pancreatic acinar markers showed marked variability and overlap. All cases showed immunoreactivity for at least one of the exocrine pancreatic enzymes, and all expressed endocrine differentiation. Some degree of amphicrine differentiation was suggested in all cases. Two cases showed metastases in perigastric lymph nodes, which histologically resembled the primary tumor. In summary, these tumors represent another distinct type of composite glandular and endocrine gastric neoplasm with pancreatic acinar differentiation.


Assuntos
Adenocarcinoma/patologia , Neoplasias das Glândulas Endócrinas/patologia , Neoplasias Epiteliais e Glandulares/patologia , Pâncreas Exócrino/patologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Feminino , Humanos , Ilhotas Pancreáticas/patologia , Masculino , Pessoa de Meia-Idade
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