Modulation of Saccade Trajectories During Sequential Saccades

The planning and execution of sequential saccades can overlap in time, and abrupt changes in neural activity in the oculomotor system can alter the normal trajectory of saccades. In this study, we analyzed saccade trajectories to assess the combined programming of sequential saccades. In two separate psychophysical experiments, subjects were instructed to make a sequence of two saccades. The results showed modulation of saccade curvature by the direction and amplitude of both the preceding and following saccade: saccade curvature is modulated in the direction of preceding saccades, and away from the direction of following saccades. Moreover, larger preceding and following saccades have stronger effects on curvature. These results support the idea that sequential saccades are programmed concurrently. Finally, the amount of saccade curvature is correlated with the deviation of saccade start and end points, and the time of maximum deviation of saccade trajectories is highly consistent in both experiments. Based on this, we propose a novel benefit for the modulation of saccade trajectories by the oculomotor system: minimizing the saccadic error in sequential saccades.

Endocrinology

The human body goes through a number of complex changes during infancy, childhood, and adolescence. This chapter provides an overview of normal growth and puberty and discusses the investigation and management of deviation from the expected ‘normal’ trajectory. Key areas of paediatric endocrine medicine, such as pituitary, hypothalamic, and thyroid pathology, are discussed. This chapter is by no means an exhaustive guide to paediatric endocrine medicine but provides an introduction that will aid clinical practice.

Sonic propagation and causal evolution for dissipative relativistic superfluid hydrodynamics

For the first time in this paper, we have studied sonic propagation and causal evolution for dissipative relativistic superfluid in the framework of second-order dissipative theory. General features of the evolution modes are provided and the sound speeds are identified as the propagation of discontinuity, in agreement with earlier theoretical studies. Moreover, the growth equation is obtained to describe the decay and growth of the discontinuity propagating along its normal trajectory. The solution is in an integral form and various cases are discussed. Some important features of the second-order theory are also presented for the first time, which may be meaningful for future experiments to identify the dissipative theory of relativistic superfluidity.

Motion Constraints and Trajectory Planning of a Planar Active Dynamic Balancing Mechanism

We propose a new solution to the active balancing issue under mechanical structural constraint. A dynamic model of the 3-DOF active balancer is established considering the limitations of the mechanical construction due to the lengths of the sliding rails. A methodology for the collision-avoidance trajectory planning is presented in addition to the normal trajectory planning to design the collision-free active balancing strategy. Numerical examples are presented to illustrate the effect of the parameter constrains as well as verify the effectiveness and necessity of trajectory planning.

Study on Vehicle Track Model in Road Curved Section Based on Vehicle Dynamic Characteristics

Plenty of experiments and data analysis of vehicle track type in road curved section show that the deviation and the crossing characteristics of vehicle track paths are directly related to the driving stability and security. In this connection, the concept of driving trajectory in curved section was proposed, six track types were classified and defined, and furthermore their characteristic features were determined. Most importantly, considering curve geometry and vehicle dynamic characteristics, each trajectory model was established, respectively, and the optimum driving trajectory models were finally determined based on the crucial factors of vehicle yaw rate, which was also the most important factor that impacts vehicle’s handling stability. Through it all, MATLAB was used to simulate and verify the correctness of models. Finally, this paper comes to the conclusion that normal trajectory and cutting trajectory are the optimum driving trajectories.