University of Texas System

About: University of Texas System is a education organization based out in Austin, Texas, United States. It is known for research contribution in the topics: Cancer & Population. The organization has 13901 authors who have published 10925 publications receiving 319328 citations. The organization is also known as: UT System.

Hypothalamic-pituitary vasculature: evidence for retrograde blood flow in the pituitary stalk.

Abstract: Retrograde transport of pituitary hormones in the pituitary stalk vasculature was investigated in anesthetized male rats in which the pituitary gland was intact and in animals in which the anterior pituitary, posterior pituitary, or entire pituitary gland had been removed 30 to 60 min before use. Blood was collected for 1.5 to 2 h by free flow from a single long portal vessel through a microcannula, the tip of which was pointed toward the hypothalamus. An arterial blood sample was obtained at the end of each collection of portal blood. The concentrations (ng\ml) of LH, TSH, prolactin, ACTH, α-MSH, and vasopressin, determined by radioimmunoassay, in portal plasma from rats with intact pituitary glands were as follows: LH, 2,320 ± 874 (mean and SE); TSH, 10,180 ± 1,471; prolactin, 4,858 ± 884; ACTH, 82 ± 17.0; a-MSH, 103 ± 17.8; vasopressin, 2.4 ± 1.0. The concentrations of these hormones in arterial plasma of these rats were as follows: LH, <20; TSH, 149 ± 22; prolactin, 25 ± 5.0; ACTH, 0.36 ± 0.05; α-MSH,...

Selective laser sintering with assisted powder handling

Abstract: A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder is deposited to the target area of the laser and attains high bulk density during sintering.