LC-oscillator with automatic stabilized amplitude via bias current control

A stable excitation supply for measurement transducers is described. It consists of a single-transistor oscillator with a coil connected to the collector and a capacitor connected from the collector to the emitter. The output of the oscillator is rectified and the rectified signal acts as one input to a differential amplifier; the other input being a reference potential. The output of the amplifier is connected at a point between the emitter of the transistor and ground. When the rectified signal is greater than the reference signal, the differential amplifier produces a signal of polarity to reduce bias current and, consequently, amplification

Automatic quadrature control and measuring system

Quadrature is separated from amplified signal by use of phase detector, with phase shifter providing appropriate reference. Output of phase detector is further amplified and filtered by dc amplifier. Output of dc amplifier provides signal to neutralize quadrature component of transducer signal

Obesity: the elephant in the corner

To date, our approach to obesity has largely been based on a simple individualistic prescription to balance energy intake against energy expenditure. This approach works for some of the people, some of the time, but is clearly not working at population level. Recognising the importance of the obesogenic environment was a crucial step forward in understanding the causes of, and potential solutions to, the emerging obesity epidemic. However, our current “environmental” responses to obesity amount to little more than marginal changes, and ignore the fact that the obesogenic environment is itself the product of the way we have chosen to organise our society. The only realistic prospect of reversing the growth in obesity lies in a decision to adopt a different set of societal priorities

Alchemy in Russian Literature

Along with sciences, alchemical activity heavily influenced literature and art, and the images of alchemists were widely reflected in the works of poets, writers, artists, philosophers and scientists. In Eastern and Western literature of ancient, medieval, and modern times, alchemy, together with the intriguing images of alchemists, was used also as a source of vivid metaphors. This article is devoted to the subject of alchemy in Russian literature, investigating which writers were interested in it and how it was developed in Russia. Prominent Russian authors’ poetic and prosaic writings have been perused throughout the research paper and it is believed that the images of alchemists portrayed by Alexander Pushkin, Nikolai Gogol, Alexander Herzen, Nikolai Ogarev, Alexei Tolstoy, and Mikhail Bulgakov were of European origin