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S D Rubenstein

Publications and source records attributed to S D Rubenstein.

22 records · Page 2Linked to original sources

Computer-assisted analysis in organic synthesis.

The planning of alternative routes for the synthesis of complex organic molecules has been facilitated by the formulation of guiding strategies that can be applied to a broad range of problems. Analysis of organic synthesis can be carried out in the retrosynthetic direction, opposite to the actual process of chemical synthesis, or bidirectionally, that is, as a combined retrosynthetic and synthetic search. An interactive computer program is described which utilizes the general strategies of retrosynthetic analysis and an appropriate database to generate pathways of chemical intermediates for chemical synthesis of a particular target structure. Computer graphics and standard chemical structures are used for man-machine communication.

Chemical Phenomena↗

Pressure--volume relationships of tracheae in fetal newborn and adult rabbits.

The physical properties of the trachea in fetal, newborn, and adult rabbits change with age. Tracheal dimensions and pressure--volume relationships were determined in excised tracheae at a wide developmental age range (from early gestational age to infancy and adulthood). At intraluminal pressures of 0 to 10 cm H2O, the tracheal specific compliance was 0.089 (cm H2O)(-1) for a 21 day old fetus. By adulthood, the tracheal specific compliance decreased five fold to 0.017 (cm H2O)(-1); a dramatic proportion of this reduction occurred during fetal life itself, followed by a steady, progressive decline to adult age. The volume of the tracheal segment, at intraluminal pressure of 20 cm H2O, increased by 29% (adult), 41.5% (31 day fetus) and 113% (21 day fetus). Developmental alterations in the specific airway compliance suggest significant changes in anatomical dead space would occur as a function of maturation and airway transmural pressure.

Aging↗