RESUMEN
A photonic-crystal (PC) resonator has attracted a great deal of attention for the strong light-matter interaction. Many attempts have been made to achieve a high-quality factor of the PC resonator, but they always have accompanied increases of modal volumes. In this work, we propose a novel method to enhance modal confinement of the PC resonator without compromising the quality factor. In the proposed structure, a thin low-index slot layer is embedded in a two-dimensional PC for vertical confinement, which results in a remarkable mode volume reduction without a decrease of the quality factor. By optimizing the slot thickness, a quality factor to mode volume ratio, which is a figure of merit for an optical resonator, could be increased by 8 times.
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We propose a high-performance, graphene-based optical modulator with a surface plasmon resonance (SPR) at 1550 nm. In the proposed device, a graphene layer is embedded in a hybrid plasmonic waveguide to enhance the light-graphene interaction. The adjustment of the permittivity of the graphene causes a significant modulation of the absorption in the SPR through a variation of the field confinement in the graphene layer, in addition to a resonant angle shift. With an optimal thickness of a metal (Ag) film and the properly chosen operation point of the Fermi level of graphene, a modulation depth of â¼100% was achieved. As the number of graphene layers in the proposed device increases, the insertion loss decreases. With five-layer graphene, a 6% insertion loss was achieved.
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A graphene-embedded tunable plasmonic nanodisk resonator operating at near-infrared wavelength range is proposed, in which a certain resonant mode among multiple whispering-gallery modes (WGMs) can be selected as a dominant mode by modulating the Fermi level of the graphene. Our theoretical investigation reveals that the dominant mode selection mechanism in the proposed resonator is governed by the figure-of-merit (FOM) of the one-dimensional (1D) waveguide of the resonator's vertical structure, which is defined as a propagation length to mode size ratio. As the conductivity of the graphene changes with a gating voltage, the wavelength dependence of the FOM changes and a WGM closest to the maximum FOM wavelength is selected. Partial tuning of the selected dominant mode is incurred by the change of the effective index of the 1D waveguide. This novel mode selection mechanism of the proposed resonator can be adopted to realize an optically pumped tunable nanolaser with a wide wavelength tuning range.
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We propose a metal nanodisk hybrid plasmonic resonator (HPR), which consists of a metallic nanodisk on top of a dielectric slab. In contrast to the previously studied plasmonic resonator structures based on metal substrates such as the nanopatch resonator, the fabrication process of the proposed resonator is much easier because of a dielectric substrate. The performance of the proposed resonator has been theoretically investigated and compared to the previously studied structures. It has been shown that the performance of the proposed resonator is superior to that of the nanopatch resonator and comparable to that of a hybrid resonator based on a metal substrate.
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Measuring patients' core body temperature during surgery is essential and commonly performed with an esophageal temperature probe. The probe must be placed in the lower third of the esophagus for accurate measurement. In this case report, we describe our experience of discovering an inadvertently malpositioned esophageal temperature probe in the right inferior lobar bronchus, which led to ventilation-related problems in a patient undergoing prostate surgery.
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Laparoscopía , Neoplasias de la Próstata , Robótica , Masculino , Humanos , Próstata , Temperatura Corporal , Temperatura , Prostatectomía/efectos adversos , Esófago/diagnóstico por imagen , Esófago/cirugía , Neoplasias de la Próstata/cirugíaRESUMEN
We propose a novel plasmonic waveguide structure, which is referred to as a circular hybrid plasmonic waveguide (HPW) and consists of a metal wire covered with low- and high-index dielectric layers. The circular HPW exhibits two distinctly different modes, namely, the strongly localized mode and the extremely low-loss mode. Our numerical calculation demonstrates that the strongly localized mode exhibits 10-4 order scale in normalized mode area and can be performed even in tens of nanometer sizes of waveguide geometry. In the extremely low-loss mode, the HPW exhibits ultra-long propagation distance of more than 103µm that can be achieved by forming the dipole-like hybrid mode and properly adjusting the radius of the metal wire. It is also shown that, even with this long-range propagation, the mode area of the dipole-like hybrid mode can be maintained at subwavelength scale. The simultaneous achievement of a small mode area and ultra-long propagation distance contributes to the ultra-high propagation distance to mode size ratio of the waveguide. The HPW results are very helpful for plasmonic device applications in the fields of low-threshold nanolasers, ultrafast modulators, and optical switches.
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Tecnología de Fibra Óptica/instrumentación , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Diseño de Equipo , Análisis de Falla de EquipoRESUMEN
OBJECTIVES: We compared the lengths of a nasoseptal flap (NSF) and skull base according to race, age, and sex. METHODS: We performed paranasal sinus computed tomography in 19,961 adult patients between 2003 and 2022. The race of the patients was East Asian (n = 71), Caucasian (n = 71), or Middle Eastern (n = 71). The expected lengths of the NSF and anterior skull base defect were measured and analyzed according to race, age, and sex. RESULTS: Compared with Caucasians and Middle Easterners, East Asians had a shorter NSF length (p < 0.001) and lower ratio of the expected NSF length to the expected defect length (p < 0.001). There was no difference in the values among age groups. The expected NSF length was longer, and the ratio of the expected NSF length to the expected defect length was higher, in males than females (p < 0.001 for both). CONCLUSIONS: East Asians and females had a shorter NSF length and lower ratio of expected NSF to surgical defect lengths after anterior skull base reconstruction compared with the other races and with males, respectively. Anatomical differences should be considered when long NSF lengths are required, such as for anterior skull base reconstruction.
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Procedimientos de Cirugía Plástica , Neoplasias de la Base del Cráneo , Masculino , Adulto , Femenino , Humanos , Puntaje de Propensión , Colgajos Quirúrgicos/cirugía , Base del Cráneo/diagnóstico por imagen , Base del Cráneo/cirugía , Neoplasias de la Base del Cráneo/cirugía , Endoscopía/métodos , Estudios RetrospectivosRESUMEN
BACKGROUND: Reexpansion pulmonary edema is a rare but potentially lethal complication. We report a case of suspected reexpansion pulmonary edema that led to cardiac arrest. CASE: A 16-year-old male patient underwent wedge resection due to right pneumothorax. The patient showed pink frothy sputum three hours following surgery, and a chest x-ray showed right unilateral pulmonary edema. Thirteen hours following surgery, the patient continuously showed pink frothy sputum and presented with severe hypoxemia, tachypnea, and tachycardia. After transferring to the intensive care unit (ICU), he developed ventricular tachycardia. Cardiopulmonary resuscitation was performed for 32 min. Chest X-ray showed diffuse bilateral pulmonary edema. Extracorporeal membrane oxygenation was performed. During the 65 days of ICU care, the patient became mentally alert. However, follow-up echocardiography revealed severe heart failure. CONCLUSIONS: Rexpansion pulmonary edema can rapidly progress to diffuse bilateral pulmonary edema. Therefore, careful observation is required for the patients who show signs of pulmonary edema after reexpansion.
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BACKGROUND: With increasing use, the incidence of adverse events associated with sugammadex, a neuromuscular blockade reverser, is increasing. This study aimed to identify and analyze cases of adverse events caused by sugammadex reported in Korean population. METHODS: Out of a total of 12 cases detected using various keywords in the Korean Journal of Anesthesia, Anesthesia and Pain Medicine (Seoul), KoreaMed, PubMed, EMBASE, Web of Science, and The Cochrane Library-CENTRAL from 2013 to December 2020, 10 cases directly associated with sugammadex were selected. RESULTS: Adverse events included five cases of anaphylaxis, one case of cardiac arrest, one case of profound bradycardia, one case of negative pressure pulmonary edema, and two cases of incomplete recovery. Three patients had American Society of Anesthesiologists physical status ≥ 3, two had emergency surgery, and two had a history of allergic reaction. Neuromuscular monitoring was applied in nine cases. The average dose of sugammadex was 2.87 mg/kg, and there were six cases in which one full vial was used, regardless of the state of neuromuscular recovery. Sugammadex was administered immediately after surgery in two cases, at train of four (TOF) 0 in four cases, at TOF 3 in one case, and after evaluation of the clinical signs only with no neuromuscular monitoring in one case. CONCLUSIONS: Even with neuromuscular monitoring, an excessive dose of sugammadex was observed. Given that adverse events tend to occur within 10 min of administration, continuous monitoring is important even after administration.
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OBJECTIVES: We estimated volume changes in the posterior bony wall of the sphenoid sinus, as well as alterations in nasal function (including olfactory function and subjective symptoms), after sphenoid mucosal repositioning using the endoscopic endonasal transsphenoidal approach (EETSA). METHODS: During 2010 and 2021, 13 patients underwent sphenoid mucosal repositioning during EETSA, while 24 patients (the control group) did not. Pre- and postoperative paranasal sinus computed tomography and the Mimics program were used to evaluate three-dimensional changes in the posterior wall of the sphenoid sinus. All patients underwent the Connecticut Chemosensory Clinical Research Center (CCCRC) test, the Cross-Cultural Smell Identification Test (CCSIT), Nasal Obstruction Symptoms Evaluation (NOSE), the Sino-Nasal Outcome Test-20 (SNOT-20), and visual analog scale (VAS) evaluation. RESULTS: The increase in the volume of the posterior wall of the sphenoid sinus after surgery was objectively smaller in the sphenoid mucosal repositioning group than in the control group (P = .046). However, this did not affect olfactory function (as revealed by the CCCRC test or the CCSIT) or subjective symptoms (as revealed by the NOSE, SNOT-20, and VAS scores) (all P > .05). CONCLUSION: Surgical closure via sphenoid mucosal repositioning during EETSA reduces the volume of the posterior wall of the sphenoid sinus and facilitates re-operation. We suggest that sphenoid mucosal repositioning is appropriate during EETSA. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:965-972, 2022.
Asunto(s)
Obstrucción Nasal , Neoplasias de la Base del Cráneo , Endoscopía/métodos , Humanos , Estudios Retrospectivos , Neoplasias de la Base del Cráneo/cirugía , Hueso Esfenoides/diagnóstico por imagen , Hueso Esfenoides/cirugía , Seno Esfenoidal/diagnóstico por imagen , Seno Esfenoidal/cirugíaRESUMEN
Spinal metabotropic glutamate receptors (mGluRs) have been known to be involved in the modulation of nociception. While the antinociceptive effects of the mGluR1/5 have been demonstrated, the role of mGluR2/3 for nociception is less clear. This study investigated the effects of an intrathecal mGluR2/3 agonist, APDC, and a mGluR2/3 antagonist, LY341495, for inflammatory and acute pain in the formalin test and thermal stimulation test. We also examined their interaction with intrathecal morphine for the antinociceptive effect. APDC had little effect on the formalin-induced nociception. In contrast, LY341495 caused a dose-dependent suppression of the phase 2 flinching response to the formalin stimulus without affecting phase 1 flinching response. Furthermore, the suppression of pain behavior by LY341495 during phase 2 was reduced significantly by pretreatment with APDC. LY341495 and morphine also showed synergistic drug interaction for antinociception during phase 2 in the formalin test.
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Analgésicos Opioides/farmacología , Analgésicos/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Morfina/farmacología , Dimensión del Dolor/efectos de los fármacos , Receptores de Glutamato Metabotrópico/antagonistas & inhibidores , Aminoácidos/farmacología , Animales , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Formaldehído , Inyecciones Espinales , Masculino , Prolina/farmacología , Ratas , Ratas Sprague-Dawley , Reflejo/efectos de los fármacos , Xantenos/farmacologíaRESUMEN
Undifferentiated pleomorphic sarcoma, previously called malignant fibrous histiocytoma, usually arises in the extremities and retroperitoneum. Primary laryngeal undifferentiated pleomorphic sarcoma is very rare, with only 63 cases having been reported in the literature as of 2015. The disease has a poor prognosis because of problems with local recurrence and metastasis. Wide resection has been recommended as a treatment modality in previous reports. We report a case of undifferentiated pleomorphic sarcoma of the vocal fold in a 64-year-old man presenting with rapid growth. The lesion was treated with type III microlaryngeal surgery followed by radiation therapy. The patient's voice was good enough for social communication, and there was no evidence of recurrence on regular examination.