Insulin encapsulated in liposomes of various lipid compositions were prepared. The amount of insulin trapped in these liposomes increased in the order, negatively charged liposomes less than neutral liposomes less than positively charged liposomes. In positively charged liposomes, the amount of insulin trapped increased with increase in the amount of amphiphile stearylamine. Under the conditions tested, the highest insulin content (about 50%) was obtained with liposomes composed of phosphatidyl choline/cholesterol/stearylamine in a molar ratio of 7/2/2.25. These liposomes were stable on incubation for 3 hr at 37 degrees C in solutions of pepsin, trypsin, and pancreatin, and after these incubations, a considerable amount of insulin was still associated with the liposomes. However, the liposomes released almost all the insulin into the medium on treatment with bile. When the liposomes were administered orally to rats in the 3rd phase of acute alloxan diabetes, reduction of the blood glucose level was observed in 7 of 11 animals, the reduction persisted for several hours and was ranging from 30 to 75%. In alloxan diabetic rats showing hyperglycemia for 3 to 6 months, the liposomes also increased the glucose tolerance in half the animals tested.

In Vehicular Ad-hoc NETwork (VANET), network performances represented by connectivity and/or throughput are much influenced by mobility patterns and densities, of vehicles. In order to improve network performance even if the density of vehicles is low, A method named Parked Vehicle Assistance (PVA) has been proposed[1]. PVA method improves network densities by introducing vehicle which is parking at a roadside, to the VANET, as a relay node of the communications (PVA node). The literature [1] reported that the performances of VANETs can be improved even if the number of PVA nodes is few. However, these performance evaluations have been conducted under the situation that the candidate nodes of PVA were randomly selected, from entire the simulation field, that is, in these evaluations PVA nodes were selected without strategies. Under the such condition, a number of needless candidate nodes will be selected as PVA nodes, and it increases needless traffic on VANETs. Then, in this paper, in order to improve VANET performance with smaller number of PVA nodes, we propose an algorithm for selecting PVA nodes in VANETs, and clarify the proposed algorithm can improve VANET performance effectively by computer simulations.

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Aminolithiation–carbolithiation tandem cyclization of an aminoalkene bearing vinyl sulfide moiety proceeded smoothly using stoichiometric amounts of BuLi. Both aminolithiation and carbo­lithiation were in equilibrium at room temperature, and the stereochemistry of the cyclization was thermodynamically controlled. At –78 °C the reaction was kinetically controlled and the cyclized product, 1,2-disubstituted octahydroindolizine, was obtained with good dia­stereoselectivity.

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