RESUMO
We theoretically demonstrate that nanocomposites made of colloidal semiconductor quantum dot monolayers placed between metal nanoparticle monolayers can function as multilayer hyperbolic metamaterials. Depending on the thickness of the spacer between the quantum dot and nanoparticle layers, the effective permittivity tensor of the nanocomposite is shown to become indefinite, resulting in increased photonic density of states and strong enhancement of quantum dot luminescence. This explains the results of recent experiments [T. Ozel et al., ACS Nano 5, 1328 (2011)] and confirms that hyperbolic metamaterials are capable of increasing the radiative decay rate of emission centers inside them. The proposed theoretical framework can also be used to design quantum-dot/nanoplasmonic composites with optimized luminescence enhancement.
RESUMO
Intramuscular neutrolysis with phenol has been used for 10 years in the management of spasticity in children. Best results depend on fastidious technique and realistic use of the procedure. Sedation or anesthesia was used in all cases -- 5% phenol in water was used for all procedures. The main indications were spasticity which interfered with function, either actual or potential, or with care. Where uninhibited vestibular or tonic neck reflexes affect muscle tone, or there is dystonia or athetosis, the procedure is less effective than where spasticity alone is present. Duration of relief of spasticity ranged from 1 month to more than 2 years. About one half of the lower extremity muscle treated required tenotomy later. Generally training was required after the procedure to obtain improved function. A representative sample of muscles treated, repeat procedures, and later surgery is discussed. The procedure is recommended for use in the management of spasticity in children as a way of improving function and/or care.