The color of polarization in cuprate superconductors

A technique for the identification of individual anisotropic grains in a heterogeneous and opaque material involves the observation of grain color in reflected light through crossed polarizers (color of polarization). Such colors are generally characteristic of particular phases. When grains of many members of the class of hole carrier cuprate superconductors are so viewed, using a xenon light source (600 K color temperature), a characteristic color of polarization is observed. This color was studied in many of these cuprate superconductors and a strong correlation was found between color and the existence of superconductivity. One of the members of the electron carrier cuprate superconductors (Nd(1.85)Ce(.15)CuO(4-x) was examined and found that it possesses the same color of polarization as all the electron hole carrier cuprate superconductors so far examined. The commonality of the characteristic color in the cuprate superconductors indicated that the presence of this color is independent of the nature of charge carriers. The correlation of this color with existence of superconductivity suggests that the origin of the color relates to the origin of superconductivity in the cuprate superconductors. Photometric techniques are also discussed

Pelvic Varices and Gonadal Veins

A prospective study of 50 cases of pelvic varices is described. Clinical history, symptoms and signs are shown emphasizing the multiple pregnancies that enlarge the gonadal veins where a high pressure escape and retrograde flow explain the vulvar and inner and posterior thigh and leg varicosities. A surgical procedure comprising resection of the gonadal veins and ligation of communicating veins to the uterine veins combined with vulvar and leg varicectomy have given excellent and encouraging early results. </jats:p

Technology entrepreneurship: creating, capturing, and protecting value

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