mechanical weeding is one of the non-chemical methods to control weeds. in this paper a ‎new mechanism has been presented for mechanical cultivation. the machine works based on ‎the manual tools operation, which farmers still use in small scale for weeding and consists of a ‎number of four-bar linkage mechanisms. each mechanism consists of a blade which moves ‎forward (active course) and backwa...

The formation of locomotor circuits depends on the spatially organized generation of motor columns that innervate distinct muscle and autonomic nervous system targets along the body axis. Within each spinal segment, multiple motor neuron classes arise from a common progenitor population; however, the mechanisms underlying their diversification remain poorly understood. Here, we show that the Fo...

A series of recent anatomical and functional data has radically changed our view on the organization of the motor cortex in primates. In the present article we present this view and discuss its fundamental principles. The basic principles are the following: (a) the motor cortex, defined as the agranular frontal cortex, is formed by a mosaic of separate areas, each of which contains an independe...

PURPOSE Cross-sectional evidence has demonstrated the importance of motor skill proficiency to physical activity participation, but it is unknown whether skill proficiency predicts subsequent physical activity. METHODS In 2000, children's proficiency in object control (kick, catch, throw) and locomotor (hop, side gallop, vertical jump) skills were assessed in a school intervention. In 2006/07...

Coherent oscillations in the theta-to-gamma frequency range have been proposed as a mechanism that coordinates neural activity in large-scale cortical networks in sensory, motor, and cognitive tasks. Whether this mechanism also involves coherent oscillations at delta frequencies (1-4 Hz) is not known. Rather, delta oscillations have been associated with slow-wave sleep. Here, we show coherent o...