RESUMO
Optical antenna structures have revolutionized the field of nano-optics by confining light to deep subwavelength dimensions for spectroscopy and sensing. In this work, we fabricated coaxial optical antennae with sub-10-nanometer critical dimensions using helium ion lithography (HIL). Wavelength dependent transmission measurements were used to determine the wavelength-dependent optical response. The quality factor of 11 achieved with our HIL fabricated structures matched the theoretically predicted quality factor for the idealized flawless gold resonators calculated by finite-difference time-domain (FDTD). For comparison, coaxial antennae with 30 nm critical dimensions were fabricated using both HIL and the more common Ga focus ion beam lithography (Ga-FIB). The quality factor of the Ga-FIB resonators was 60% of the ideal HIL results for the same design geometry due to limitations in the Ga-FIB fabrication process.
RESUMO
OBJECTIVE: This study aims at presenting the evolution of the embolization technique in treating renal angiomyolipomas (AMLs) either diagnosed in patients with acute bleeding or discovered accidentally. METHODS: Ten patients with renal AMLs have been through thirteen selective transcatheter arterial embolizations for 15 years. Two patients had tuberous sclerosis complex (TSC) with bilateral tumors and were embolized twice. Four embolic materials were employed: PVA particles, Gianturco coils, microspheres and microcoils. Catheterization was achieved by means of 5F Cobra 2 catheters and coaxial microcatheter systems. RESULTS: On an emergency basis, embolization was a first-line treatment. In one case, surgery was necessary; in two patients, a second embolization was performed. When treatment was preventive, a single embolization proved to be sufficient, as well. There was no significant deterioration of the serum creatinine levels in the post-embolization period. CONCLUSION: Selective arterial embolization is a rather safe and effective technique to treat AMLs both urgently and preventively. Different embolic materials can be employed. Microspheres and microcatheters stand for new promising materials.
Assuntos
Angiomiolipoma/terapia , Embolização Terapêutica/métodos , Embolização Terapêutica/tendências , Neoplasias Renais/terapia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Resultado do TratamentoRESUMO
A survey was completed of US pediatric residency programs about the use of community sites in training. A total of 85% of program directors responded and reported a wide use of the 21 identified survey sites. Further study is needed to determine the appropriate contribution that community sites can make to pediatric training.