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1.
J Phys Condens Matter ; 34(26)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35417887

RESUMEN

Surface phonon-polariton, surface plasmon-polariton, and surface phonon-plasmon-polariton are evanescent electromagnetic waves confined to the surfaces of different classes of materials, which gives each of them particular characteristics suitable for diverse applications. Natural or forced injection of free carriers in a dielectric may change the surface phonon-polariton into a surface phonon-plasmon-polariton. Understanding this effect provides an insight into the fundamental physics of surface electromagnetic waves on dielectrics and offers tools that can be used to develop new technologies. In this contribution, we experimentally study the transition from surface phonon-polariton to surface phonon-plasmon-polariton on a yttrium-doped aluminum nitride polycrystalline substrate by thermal injection of free carriers. We perform this study using reflectivity measurements in the far- and mid-infrared spectral range and at a variable temperature, taking the necessary precautions to eliminate any errors that may arise from measurement artifacts and inaccurate analysis of the spectra. We demonstrate that thermal injection of a significant free carrier density can tune the surface phonon-polariton into a much shorter mean free path surface phonon-plasmon-polariton.

2.
Sci Rep ; 12(1): 2346, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35173182

RESUMEN

Graphene is known as an atomically thin, transparent, highly electrically and thermally conductive, light-weight, and the strongest 2D material. We investigate disruptive application of graphene as a target of laser-driven ion acceleration. We develop large-area suspended graphene (LSG) and by transferring graphene layer by layer we control the thickness with precision down to a single atomic layer. Direct irradiations of the LSG targets generate MeV protons and carbons from sub-relativistic to relativistic laser intensities from low contrast to high contrast conditions without plasma mirror, evidently showing the durability of graphene.

3.
Bone Joint J ; 99-B(12): 1643-1650, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29212688

RESUMEN

AIMS: We conducted a study to identify factors that are prognostic of the outcome of extracorporeal shockwave therapy (ESWT) for calcific tendinitis of the shoulder. PATIENTS AND METHODS: Since 1998, patients with symptomatic calcific tendinitis of the rotator cuff have been treated with ESWT using an electrohydraulic mode shockwave device. One year after ESWT, patients were grouped according to the level of resorption of calcification. RESULTS: Of 241 symptomatic shoulders, complete resorption (CR) of calcification occurred in 134 (CR group). The remaining 107 shoulders had incomplete resorption (ICR) (ICR group). Gartner type I calcification was most common (64.5%) in the ICR group. The mean duration of symptoms before ESWT was significantly longer in the ICR group. Overall, 81% of the CR group and 23.4% of the ICR group were symptom free. There was a strong relationship between subsidence of symptoms and remission of calcification. Poor prognosis was significantly related to Gartner type I calcification, calcification extent > 15 mm and duration of symptoms > 11 months. CONCLUSION: Patients with calcific tendinitis of the shoulder who have the factors identified for a poor outcome after ESWT should undergo a different procedure. Cite this article: Bone Joint J 2017;99-B:1643-50.


Asunto(s)
Calcinosis/terapia , Tratamiento con Ondas de Choque Extracorpóreas , Manguito de los Rotadores , Dolor de Hombro/terapia , Hombro , Tendinopatía/terapia , Adulto , Anciano , Calcinosis/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Rango del Movimiento Articular , Manguito de los Rotadores/diagnóstico por imagen , Hombro/diagnóstico por imagen , Dolor de Hombro/etiología , Tendinopatía/diagnóstico por imagen , Resultado del Tratamiento
4.
Opt Express ; 25(16): 18853-18862, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-29041077

RESUMEN

Fully integrated monolithic, multi-channel InP-based coherent receiver PICs and transceiver modules with extended C-band tunability are described. These PICs operate at 33 and 44 Gbaud per channel under dual polarization (DP) 16-QAM modulation. Fourteen-channel monolithic InP receiver PICs show integration and data rate scaling capability to operate at 44 Gbaud under DP 16-QAM modulation for combined 4.9 Tb/s total capacity. Six channel simultaneous operation of a commercial transceiver module at 33 Gbaud is demonstrated for a variety of modulation formats including DP 16-QAM for >1.2Tbit/s aggregate data capacity.

5.
J Biophotonics ; 9(8): 827-36, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27093912

RESUMEN

Nanodiamond (ND) has been proposed for various biomedical applications, including bioimaging, biosensing and drug delivery, owing to its physical-chemical properties and biocompatibility. Particularly, ND has been demonstrated as fluorescence- and Raman-detectable labels in many cellular models. Different surface functionalization methods have been developed, varying the ND's surface properties and rendering the possibility to attach biomolecules to provide interaction with biological targets. For this, toxicity is of major concern in animal models. Aside from cellular models, a cost-effective animal test will greatly facilitate the development of applications. In this study, we use the rapid, sensitive and reproducible zebrafish embryo model for in vivo nanotoxicity test. We optimize the conditions for using this animal model and analyze the zebrafish embryonic development in the presence of ND. ND is observed in the embryo in vivo using laser confocal fluorescence microscopy and fluorescence lifetime imaging. Using the zebrafish model for a safety evaluation of ND-based nanolabel is discussed.


Asunto(s)
Nanodiamantes , Pruebas de Toxicidad , Pez Cebra/embriología , Animales , Microscopía Confocal , Microscopía Fluorescente , Propiedades de Superficie
6.
Opt Express ; 19(26): B154-8, 2011 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-22274012

RESUMEN

In this work, a 10-wavelength, polarization-multiplexed, monolithically integrated InP coherent QPSK transmitter PIC is demonstrated to operate at 112 Gb/sec per wavelength and total chip superchannel bandwidth of 1.12 Tb/s. This demonstration suggests that increasing data capacity to multi-Tb/s per chip is possible and likely in the future.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(3 Pt 1): 031408, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16241436

RESUMEN

Magnetite nanoparticles with diameters of 7, 9, and 12 nm have been prepared by a chemical coprecipitation method. The transmission of light through magnetic fluid containing these nanoparticles has been investigated as a function of film thickness with wavelength between 400 and 750 nm, and applied magnetic fields up to 275 Oe. The transmission threshold shifts to the lower wavelength side with decreasing magnetic fluid film thickness as well as the particle size. For a given film thickness, the transmittance increases with increasing magnetic field for films with a particle size of 7 and 9 nm, but decreases in the 12-nm film. This is attributed to the competition between the van der Waals and dipole-dipole interaction.

8.
J Agric Food Chem ; 49(11): 5461-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11714344

RESUMEN

Five kinds of ear mushrooms are commercially available in Taiwan, including black, red, jin, snow, and silver ears. Methanolic extracts were prepared from these ear mushrooms, and their antioxidant properties were studied. For all methanolic extracts from ear mushrooms, the antioxidant activities in the 1,3-diethyl-2-thiobarbituric acid method were moderate (38.6 approximately 74.6%) at 1.0-5.0 mg/mL. Methanolic extracts from red, jin, and snow ears showed excellent antioxidant activities in the conjugated diene method at 5.0 mg/mL. At 5.0 mg/mL, reducing powers of methanolic extracts were in the descending order of snow > black approximately red approximately jin > silver ears. The scavenging effect of methanolic extracts from ear mushrooms on 1,1-diphenyl-2-picrylhydrazyl radicals was excellent except for that from silver ears. Ear mushroom extracts were not good scavengers for hydroxyl free radicals but were good chelators for ferrous ions. Naturally occurring antioxidants, including ascorbic acid, tocopherols, and total phenols, were found in the methanolic extracts. However, beta-carotene was not detected. Total antioxidant components were 15.69, 30.09, 27.83, 49.17, and 31.70 mg/g for black, red, jin, snow, and silver ears, respectively.


Asunto(s)
Agaricales/química , Antioxidantes/química , Bepridil/análogos & derivados , Picratos , Bepridil/química , Compuestos de Bifenilo , Depuradores de Radicales Libres/química , Radical Hidroxilo/química , Metanol/química , Oxidación-Reducción
9.
JAMA ; 280(4): 329-35, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9686549

RESUMEN

CONTEXT: Studies have demonstrated strong associations between the prone sleep position (on the stomach) and sudden infant death syndrome (SIDS). In 1992, the American Academy of Pediatrics recommended that infants be placed to sleep laterally (on their side) or supine (on their back) to reduce SIDS risk, and in 1994, the national public education campaign "Back to Sleep" was launched. OBJECTIVE: To determine the typical sleep position of infants younger than 8 months in the United States, the changes that occurred after these recommendations, and the factors associated with the placement of infants prone or supine. DESIGN: Annual nationally representative telephone surveys. SETTING: The 48 contiguous states of the United States. PARTICIPANTS: Nighttime caregivers of infants born within the last 7 months between 1992 and 1996. Approximately 1000 interviews were conducted per year. MAIN OUTCOME MEASURES: The position the infant was usually placed in for sleep, and the position the infant was most commonly found in when checked during the night's sleep. RESULTS: Ninety-seven percent of respondents in each wave of the survey usually placed their infant to sleep in a specific position. Infants were placed in the prone position by 70% of caregivers in 1992, prior to the campaign, but only 24% in 1996. Supine and lateral placements increased during this time period, from 13% in 1992 to 35% in 1996 and from 15% in 1992 to 39% in 1996, respectively. Significant predictors of prone placement included maternal race reported as black (odds ratio [OR], 2.34; 95% confidence interval [CI], 1.68-3.26), mother's age 20 to 29 years (OR, 1.28; 95% CI, 1.09-1.50), region reported as the mid-Atlantic (OR, 1.41; 95% CI, 1.12-1.78) or southern states (OR, 1.47; 95% CI, 1.22-1.70), mothers with a previous child (OR, 1.68; 95% CI, 1.43-1.97), and infants younger than 8 weeks (OR, 0.63; 95% CI, 0.46-0.85). Infants aged 8 to 15 weeks were significantly more likely to be placed nonprone over time compared with the other age groups. Most of the risk factors for prone were significantly related in the opposite direction to supine placement. CONCLUSIONS: The prevalence of infants placed in the prone sleep position declined by 66% between 1992 and 1996. Although causality cannot be proved, SIDS rates declined approximately 38% during this period. To achieve further reduction in prone sleeping, efforts to promote the supine sleep position should be aimed at groups at high risk for prone placement.


Asunto(s)
Cuidado del Lactante/normas , Posición Prona , Sueño , Muerte Súbita del Lactante/prevención & control , Posición Supina , Guías como Asunto , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Análisis Multivariante , Vigilancia de la Población , Factores de Riesgo , Muerte Súbita del Lactante/epidemiología , Estados Unidos/epidemiología
10.
Laryngoscope ; 107(8): 1129-37, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9261021

RESUMEN

Optimal management of advanced neck metastases as part of an organ preservation treatment approach for head and neck squamous carcinoma (HNSC) is unclear. Since 1989, our management paradigm for patients on organ preservation was modified to incorporate planned early neck dissection before radiation therapy for patients who did not achieve a complete response (CR) of neck nodes after induction chemotherapy (IC). The purpose of this study was to determine if planned early neck dissection is a safe and effective approach in the management of advanced nodal disease as part of organ preservation. Fifty-eight consecutive patients with advanced HNSC who were entered in organ preservation trials using induction chemotherapy and radiation with surgical salvage were studied. Median follow-up was 26 months. Of the 58 patients, 71% were stage IV. Patients were grouped by nodal response to chemotherapy and N class, and were analyzed with respect to patterns of recurrence, complications, and survival. Overall, the rate of CR of neck nodes was 49%. Fifty-one percent had less than a complete response of neck nodes after IC and required planned early neck dissection. There were no significant differences in patterns of recurrence, complications, interval time to start of radiation, recurrence, or survival rates between the CR and less than CR groups. These data suggest that planned early neck dissection for patients with less than CR in the neck after IC is not detrimental with respect to neck relapse or overall survival. We believe that planned early neck dissection can be safely incorporated into future organ preservation treatment protocols for patients with advanced head and neck carcinoma.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Disección del Cuello , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos , Terapia Recuperativa , Análisis de Supervivencia
12.
Artículo en Inglés | MEDLINE | ID: mdl-7572175

RESUMEN

Systemic candidiasis with renal involvement is a relatively rare infectious process in young infants. The mortality rate in the cases reported to date has been lower after aggressive surgical and medical management. This report concerns a three-month-old, prematurely born infant with a fatal systemic candidiasis and acute renal failure. Renal pelvic fungal balls caused ureteropelvic junction obstruction in this patient. Renal ultrasonography demonstrated bilateral obstructive uropathy. Treatment consisted of surgical removal of the bezoar, together with open placement of nephrostomy tubes, parenteral amphotericin B therapy and peritoneal dialysis. This case emphasizes the need for a highly suspicion of renal obstruction by fungal balls in any high risk infant with systemic candidiasis and renal dysfunction.


Asunto(s)
Lesión Renal Aguda/etiología , Bezoares/complicaciones , Candidiasis/complicaciones , Recien Nacido Prematuro , Pelvis Renal , Uréter , Humanos , Lactante , Recién Nacido , Masculino , Obstrucción Ureteral/etiología
15.
J Anal Toxicol ; 4(3): 127-31, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6999237

RESUMEN

Methylglyoxal-bis(guanylhydrazone), Methyl-G, is a potent antineoplastic agent currently undergoing Phase l clinical trials. Serum, ascitic and pleural fluids, and urine are deproteinized with methanol, supernatant is evaporated, residue is redissolved in the eluent, lipids are removed with carbon tetrachloride, and an aliquot of the aqueous layer injected into the chromatograph. Ethylglyoxal-bis(guanylhydrazone) (Ethyl-G) is the internal standard. The mobile phase is a mixture of an aqueous buffer (containing 0.004 M heptane and pentane sulfonic acid, 90%:10%, buffered to pH 3.5) and methanol (68%:32%). The ion-pair complex is retained on a micro Bondapak C18 column, eluted with a flow of 2.0 mL/min. Absorbance is measured at 280 nm. Detectability: 30 ng/mL (0.11 micro M) in serum, ascitic and pleural fluids, 300 ng/mL (1.1 micro M) in urine. Calibration curves (peak height ratios of Methyl-G/Ethyl-G plotted against known drug concentrations) were linear in the 0.1-30 microg/mL range. Correlation coefficinets were 0.999; coefficients of variation for reproducibility were less than 5%. Residual blood levels of Methyl-G persist for several days. Methyl-G was found to pass into ascitic fluid.


Asunto(s)
Líquidos Corporales/análisis , Cromatografía por Intercambio Iónico/métodos , Guanidinas/análisis , Mitoguazona/análisis , Líquido Ascítico/análisis , Ensayos Clínicos como Asunto , Humanos , Mitoguazona/sangre , Mitoguazona/orina , Derrame Pleural/análisis
16.
J Cardiovasc Surg (Torino) ; 17(5): 420-5, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-972159

RESUMEN

Eighty-six consecutive patients operated on for atherosclerotic occlusion of the aortoiliac segment were examined regarding the severity of the disease in the left or right iliac arteries. Sixty-nine percent of 78 patients were found to have predominantly more severe lesions on the left side. A study of the geometric anatomy of the aortoiliac region in 14 male and 12 female cadavers revealed that the right common iliac take-off angle was wider than the left and the radius of curvature of the right osculating circle at the aortoiliac bifurcation was smaller than the left, with the asymmetry of the region being much more marked in males than in females. The predilection of occlusive disease for the left iliac artery is explained on the basis of these differences in local geometric anatomy and their effect on the local hemodynamics.


Asunto(s)
Arteriopatías Oclusivas/cirugía , Arteria Ilíaca/cirugía , Adulto , Anciano , Femenino , Humanos , Arteria Ilíaca/anatomía & histología , Masculino , Persona de Mediana Edad , Reología
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