Published: Jan. 1, 2014
While metal nanoparticles are being increasingly used in many sectors of the economy, there is growing interest in the biological and environmental safety of their production. The main methods for nanoparticle production are chemical and physical approaches that are often costly and potentially harmful to the environment. The present review is devoted to the possibility of metal nanoparticle synthesis using plant extracts. This approach has been actively pursued in recent years as an alternative, efficient, inexpensive, and environmentally safe method for producing nanoparticles with specified properties. This review provides a detailed analysis of the various factors affecting the morphology, size, …
Published: May 31, 2014
The mesolimbic dopamine system is believed to be a key component in the processing of rewarding information by the brain, although the precise nature of dopamine release remains unknown. Avoidance conditioning combines reward (positive) and aversion (negative) phenomena. Here the activity of 60 neurons in the ventral tegmental area (VTA) was studied in freely moving rabbits during the acquisition and performance of an active avoidance. A total of 48 % of the recorded neurons responded to the conditioned stimulus (CS). A significant predominance of excitatory responses to the (CS) was demonstrated. Two main patterns of cell responses to the CS …