Confluent human aortic endothelial cells (HAECs) cultured on thermo-responsive culture dish grafted with poly (N-isopropylacrylamide) were recovered as a contiguous cell sheet. The double-layered co-culture was achieved by placing the recovered HAEC sheet onto the rat hepatocyte layer directly. The double-layered structure of HAEC and hepatocytes remained in tight contact during culture. Hepatocytes in the layered co-culture system with the HAEC sheet maintained the differentiated cell shape and the albumin expression for over 41 days of culture, whereas the functions disappeared within 10 days of culture in control hepatocytes without the HAEC sheet. The layered co-culture of hepatocytes and the HAEC sheets, which allows for the expression of differentiated functions of hepatocyte continuously, such as liver lobule, offers a major advancement in liver tissue engineering.
When integrating signals from vision and haptics the brain must solve a "correspondence problem" so that it only combines information referring to the same object. An invariant spatial rule could be used when grasping with the hand: here the two signals should only be integrated when the estimate of hand and object position coincide. Tools complicate this relationship, however, because visual information about the object, and the location of the hand, are separated spatially. We show that when a simple tool is used to estimate size, the brain integrates visual and haptic information in a near-optimal fashion, even with a large spatial offset between the signals. Moreover, we show that an offset between the tool-tip and the object results in similar reductions in cross-modal integration as when the felt and seen positions of an object are offset in normal grasping. This suggests that during tool use the haptic signal is treated as coming from the tool-tip, not the hand. The brain therefore appears to combine visual and haptic information, not based on the spatial proximity of sensory stimuli, but based on the proximity of the distal causes of stimuli, taking into account the dynamics and geometry of tools.
We present early pilot-studies of a new international project, developing advanced robotics to handle nuclear waste. Despite enormous remote handling requirements, there has been remarkably little use of robots by the nuclear industry. The few robots deployed have been directly teleoperated in rudimentary ways, with no advanced control methods or autonomy. Most remote handling is still done by an aging workforce of highly skilled experts, using 1960s style mechanical Master-Slave devices. In contrast, this paper explores how novice human operators can rapidly learn to control modern robots to perform basic manipulation tasks; also how autonomous robotics techniques can be used for operator assistance, to increase throughput rates, decrease errors, and enhance safety. We compare humans directly teleoperating a robot arm, against humansupervised semi-autonomous control exploiting computer vision, visual servoing and autonomous grasping algorithms. We show how novice operators rapidly improve their performance with training; suggest how training needs might scale with task complexity; and demonstrate how advanced autonomous robotics techniques can help human operators improve their overall task performance. An additional contribution of this paper is to show how rigorous experimental and analytical methods from human factors research, can be applied to perform principled scientific evaluations of human test-subjects controlling robots to perform practical manipulative tasks.
Gripper
CameraSample test rig 7 DOF Robot Test objects for stacking task
Collectively, the results are consistent with there being an increased degree of background cortical hyperexcitability in the cortices of individuals predisposed to some ABE-type hallucinations, even in the nonclinical population. The present study also establishes the clinical utility of the pattern-glare task for examining signs of aberrant visual connectivity in relation to visual hallucinations.
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