Consistency maintenance of Do and Undo/Redo operations in real-time collaborative bitmap editing systems

In real-time collaborative graphical editing systems, bitmap-based graphical editing systems are particularly special and practically useful ones, and Do and Undo/Redo operations are intricate problems in this field. However, existing researches on graphical editing systems are quite scanty. In this paper, based on Multi-version strategy, we propose a new approach to solve the Do and Undo/Redo consistency maintenance problems with due consideration of three possible cases: all-causal, all-independent and causal-independent-mixed operations. Compared with previous collaborative algorithms, the algorithms proposed in this paper support Do and Undo/Redo operations without requiring additional space. In addition, two example analyses are also given to prove the algorithms’ effectiveness separately. Furthermore, the time complexity of the two algorithms is both O(n). Finally, a system prototype called bitmap-based Co-Graphical Editor is implemented to verify them realistically.     

Dynamical stress characterization and energy evaluation of single cardiac myocyte actuating on flexible substrate

Contractility estimation of cardiac myocyte is important for power evaluation of the cell in heart performance. In this paper, we used digital image correlation (DIC) method to obtain dynamic deformation field of the flexible substrate distributively actuated by single cardiac myocyte, which resulted in the dynamic history of traction forces of the cell during contraction-relaxation cycles. Furthermore, the resultant work and power of the single neonatal cardiac myocyte was evaluated to show the energy characteristics of the cells and the responses to the stiffness variation of the substrate. The method provides a useful tool to study behaviors of the cardiac myocytes interacted with the substrates.     

Narcolepsy in orexin knockout mice: molecular genetics of sleep regulation.

Neurons containing the neuropeptide orexin (hypocretin) are located exclusively in the lateral hypothalamus and send axons to numerous regions throughout the central nervous system, including the major nuclei implicated in sleep regulation. Here, we report that, by behavioral and electroencephalographic criteria, orexin knockout mice exhibit a phenotype strikingly similar to human narcolepsy patients, as well as canarc-1 mutant dogs, the only known monogenic model of narcolepsy. Moreover, modafinil, an anti-narcoleptic drug with ill-defined mechanisms of action, activates orexin-containing neurons. We propose that orexin regulates sleep/wakefulness states, and that orexin knockout mice are a model of human narcolepsy, a disorder characterized primarily by rapid eye movement (REM) sleep dysregulation.