Directional solidification, thermo-mechanical and optical properties of (Mg(x)Ca(1-x))(3)Al(2)Si(3)O(12) glasses doped with Nd(3+) ions.

In this work glass rods of (Mg(x)Ca(1-x))(3)Al(2)Si(3)O(12) (x = 0, 0.5 and 1) doped with 1 wt% Nd(2)O(3) were produced by the laser floating zone technique. Thermo-mechanical and spectroscopic properties have been evaluated. The three glass samples present good thermo-mechanical properties, with similar hardness, toughness and glass transition temperatures. The spectroscopic characterization shows spectral shifts in absorption and emission spectra. These spectral shifts together with Judd-Ofelt intensity parameters and ionic packing ratio have been used to investigate the local structure surrounding the Nd(3+) ions and the covalency of the Nd-O bond. All obtained results agree and confirm the higher covalency of the Nd-O bond in the Ca(3)Al(2)Si(3)O(12) glass.

Tiempo de reevaluar los bisfosfonatos y de revisar la regulación de medicamentos y nuestras actitudes / Time to reassess bisphosphonates, Drug regulations, and rethink our attitudes

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Aural myiasis caused by cochliomyia hominivorax: case report

This is a case of aural human myiasis caused by Cochliomyia hominivorax, a rare etiologic insect in Belize, Central America. A definite diagnosis was made by identifying the larvae, which were removed and sent for identification. Perforation of the drum, and migration of the larvae to the middle ear and mastoid cavity developed in this case within 48 hours. The larvae were removed from the infested regions surgically. Myringoplasty was performed and the patients hearing restored (AU)

Arterio-venous access utilizing modified bovine arterial grafts for hemodialysis.

Forty-seven patients with chronic renal failure presenting with a loss of vascular access precluding hemodialysis were subjected to 105 surgical procedures to establish and to maintain an arteriovenous fistulae. 67 bovine heterografts were implanted over a 30 month period and observed for 6 or more months. Fifteen, or 32% of the patients, died during the study period. Eleven patients died with a functional fistula. Twenty fistulae continued to function at the end of 36 months constituting a 46.3% graft survival rate. Hemodialysis was continued in 11 of 12 patients via a P.T.F.E. Goretex graft or via a matured Brescia Fistula. The remaining patient experienced graft failure at the end of the study period. Graft thrombosis was observed in 31 of 67 grafts placed (46%). Successful thrombectomy was achieved in 52%. Fourteen grafts developed frank aneurysms with overt rupture in 8. All patients with aneurysms were negro. Six of 8 patients with aneurysm presented with severe hypertension. Thirteen aneurysms were resected without loss of life or limb. The use of bovine grafts in hypertensive negro patients is believed to be contraindicated.