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Scatter Factor/Hepatocyte Growth Factor and Its Receptor, the c-met Tyrosine Kinase, Can Mediate a Signal Exchange between Mesenchyme and Epithelia during Mouse Development
Full text linkScatter factor/hepatocyte growth factor
(SF/HGF) has potent motogenic, mitogenic, and morphogenetic
activities on epithelial cells in vitro. The cell
surface receptor for this factor was recently identified:
it is the product of the c - m e t protooncogene, a
receptor-type tyrosine kinase. We report here the
novel and distinct expression patterns of SF/HGF and
its receptor during mouse development, which was determined
by a combination of in situ hybridization and
RNase protection experiments. Predominantly, we detect
transcripts of c - m e t in epithelial cells of various
developing organs, whereas the ligand is expressed in
distinct mesenchymal cells in close vicinity. In addition,
transient SF/HGF and c - m e t expression is found
at certain sites of muscle formation; transient expression
of the c - m e t gene is also detected in developing
motoneurons. SF/HGF and the c-met receptor might
thus play multiple developmental roles, most notably,
mediate a signal given by mesenchyme and received
by epithelial. Mesenchymal signals are known to govern
differentiation and morphogenesis of many epithelia,
but the molecular nature of the signals has remained
poorly understood. Therefore, the known
biological activities of SF/HGF in vitro and the embryonal
expression pattern reported here indicate that
this mesenchymal factor can transmit morphogenetic
signals in epithelial development and suggest a molecular
mechanism for mesenchymal epithelial interactions
The clusters growth and evaporation rate constante calculation by using of molecular dynamics method for condensation behind the shock front
Full text linkMolecular dynamics model of calculation of the growth and evaporation rate constants of
dusters is proposed. Calculations for small clusters are carried out. On the basis of the
chemical mechanism the characteristic time of condensation is achieved, which is in available
agreement with experiment on condensation of iron vapors behind the shock front
Existence, Uniqueness, and Numerical Analysis of Solutions of a Quasilinear ParabolicProblem
Full text linkA quasilinear parabolic problem is studied. By using the method of lines, the existence and uniqueness of a solution to the initial boundary value problem with sufficiently smooth initial conditions are shown. Also given are L2 error estimates for the error between the extended fully discrete finite element solutions and the exact solution
REAL TIME PREDICTIVE CONTROL OF UR5 ROBOTIC ARM THROUGH HUMAN UPPER LIMB MOTION TRACKING
No full textThis thesis reports the authors’ results on developing a real-time predictive
control system for an Universal Robot UR5 robotic arm through human
motion capture with a visualization environment built in the Blender Game Engine.
The UR5 is a 6 degree of freedom serial manipulator commonly used
in academia and light industry. It is a very safe robot by design that comes
at a cost of a rather limited API with very little support of real-time operation.
The motion tracking is performed by a wireless low-cost inertial motion capture
setup produced in-house. The motion tracker is an extension of author’s previous
work on replacing a forearm IMU in conventional inertial motion tracking
suits with a potentiometer in order remove anatomical constraints from corresponding
data fusion algorithms. The external controller incorporates an iTaSC
SDLS IK solver and a Python wrapped C explicit model predictive controller
generated using the Multi Parametric Toolbox. The visualisation provides the
user with the feedback on the robot’s progress towards the target. It is planned
to extend the visualisation to virtual reality in future.
Tests have shown that the robot follows the operator’s wrist position and
orientation with an average of 0.05sec. time lag in the case when the operator
moves under the robot’s velocity and acceleration limits. When the operator
moves too fast for the robot to keep up in real-time, the robot is able to catch
up with the operator with little or no overshooting. Thesis results are described
in a late-breaking report and demo accepted by the 12th annual IEEE/ACM
international conference Human-Robot Interaction (HRI2017)