Feasibility of a one–step process for desizing,scouring, bleaching and mercerisating cotton fabrics

In this study the desizing, scouring, bleaching and slack mercerising of cotton fabric by a one–step process at different sodium hydroxide concentrations, impregnation temperatures and curing times were examined. The results indicate that when the fabrics are mercerised at lower temperature, the strength retention and colour strength are enhanced. When the sodium hydroxide concentration is increased, these properties also increase. When cotton fabrics are mercerised for 3 min at 40C and cured for 30 s at 120C, their physical properties are similar to those obtained using a conventional two–step approach.     

A method for detecting structure in polyhedra

A construction is given for associating a finite state automaton with a 3-dimensional polyhedron. It has the property that if a polyhedral segment is encoded as a string and used as input to the automaton, the automaton state which is reached contains information about all congruences of the segment with parts of the polyhedral surface. An application is retrieval from a polyhedral database, given as key a partial 3D view.     

Pheromone regulated production of inositol-(1, 4, 5)-trisphosphate in the mammalian vomeronasal organ

Social behaviors of most mammals are profoundly affected by chemical signals, pheromones, exchanged between conspecifics. Pheromones interact with dendritic microvilli of bipolar neurons in the vomeronasal organ (VNO). To investigate vomeronasal signal transduction pathways, microvillar membranes from porcine VNO were prepared. Incubation of such membranes from prepubertal females with boar seminal fluid or urine results in an increase in production of inositol-(1, 4, 5)-trisphosphate (IP3). The dose response for IP3 production is biphasic with a GTP-dependent component at low stimulus concentrations and a nonspecific increase in IP3 at higher stimulus concentrations. The GTP-dependent stimulation is mimicked by GTPgammaS and blocked by GDPbetaS. Furthermore, the GTP-dependent component of the stimulation of IP3 production is sex specific and tissue dependent. Studies with monospecific antibodies reveal a G alpha(q/11)-related protein in vomeronasal neurons, concentrated at their microvilli. Our observations indicate that pheromones in boar secretions act on vomeronasal neurons in the female VNO via a receptor mediated, G protein-dependent increase in IP3. These observations set the stage for further investigations on the regulation of stimulus-excitation coupling in vomeronasal neurons. The pheromone-induced IP3 response also provides an assay for future purification of mammalian reproductive pheromones.     

Sputtered platinum films on colloidal gold particles: a calibration specimen for quartz film thickness monitors

A method for calibrating quartz crystal thickness monitors is described, which makes use of 20 nm platinum sputtered colloidal gold particles. The actual thickness is measured on transmission electron micrographs of gold particles protruding from the edge of fractured, rolled up, carbon films. In the range up to ～10 nm, the measured thickness for platinum films is ～17% larger than the figures calculated from mass thickness equations.