Quantized controller for a class of uncertain nonlinear systems with dead-zone nonlinearity.

In this paper, a quantized controller is designed for a class of uncertain nonlinear systems subjected to unknown disturbances and unknown dead-zone nonlinearity. A general class of strict feedback nonlinear systems is taken as the plant to design the controller. Here, each differential equation of the system is considered to have unknown parameters and time-varying disturbances.

Donor-acceptor substituted cyclopropane to butanolide and butenolide natural products: enantiospecific first total synthesis of (+)-hydroxyancepsenolide.

An oxygen substituted donor-acceptor cyclopropane (DAC) is used as a common intermediate in the enantiospecific collective total synthesis of butanolide- and butenolide-based natural products like (+)-juruenolide C and D, (+)-blastmycinone, (+)-antimycinone, and (+)-ancepsenolide. Enantiospecific first total syntheses of (+)-hydroxyancepsenolide and its acetate are achieved confirming their absolute stereochemistry.

Management of complex long bone nonunions using limb reconstruction system.

Background: Management of complex nonunions is difficult due to the presence of infection, deformities, shortening and multiple surgeries in the past. Complex nonunions are traditionally managed by Ilizarov fixation. The disadvantages of Ilizarov are poor patient compliance, inconvenience of the frame and difficult frame construction.

Characteristics of long-term cultures of avian primordial germ cells and gonocytes.

Avian cell lines derived from germinal crescent primordial germ cells and gonadal gonocytes with long-term proliferative capacity in vitro and their subsequent rates of colonization and germline transmission are described. In general, male cultures proliferate more rapidly than female cultures although both can be developed into cell lines of >2 × 10(6) cells, at which time, they can be grown indefinitely and a cell bank can be established. All the cell lines injected into embryos transmitted through the germline with the percentage of germline transmission of both male and female cell lines varying from single digits to the high 90s.