No abstract

The plasma membrane of a cell not only works as a physical barrier but also mediates the signal relay between the extracellular milieu and the cell interior. Various stimulants may cause the redistribution of molecules, like lipids, proteins, and polysaccharides, on the plasma membrane and change the surface potential (Φ s ). In this study, the Φ s s of PC12 cell plasma membranes were measured by atomic force microscopy in Kelvin probe mode (KPFM). The skewness values of the Φ s s distribution histogram were found to be mostly negative, and the incorporation of negatively charged phosphatidylserine shifted the average skewness values to positive. After being treated with H 2 O 2 , dopamine, or Zn 2+ , phosphatidylserine was found to be translocated to the membrane outer leaflet and the averaged skewness values were changed to positive values. These results demonstrated that KPFM can be used to monitor cell physiology status in response to various stimulants with high spatial resolution.

The low-energy electronic states and energy gaps of carbon nanocones in an electric field are studied using a single-S-band tight-binding model. The analysis considers five perfect carbon nanocones with disclination angles of 60°, 120°, 180°, 240° and 300°, respectively. The numerical results reveal that the low-energy electronic states and energy gaps of a carbon nanocones are highly sensitive to its geometric shape (i.e. the disclination angle and height), and to the direction and magnitude of an electric field. The electric field causes a strong modulation of the state energies and energy gaps of the nanocones, changes their Fermi levels, and induces zero-gap transitions. The energy-gap modulation effect becomes particularly pronounced at higher strength of the applied electric field, and is strongly related to the geometric structure of the nanocone. Many theoretical [5][6][7][8][9][10] and experimental studies [11][12][13][14] of the geometric and electronic properties of carbon nanocones or nanotube tips have been revealed over the past decade. In general, the results have shown that the electronic structure, e.g. the electronic states, energy gaps and density of states, are highly sensitive to the symmetry of the edge sites at the open apex and to the curvature effect. However, relatively few studies have investigated the effect of an electric field on the electronic structures of carbon nanocones. It is known that an electric field can significantly affect the electronic properties of

This study presents a novel computer-based virtual ping-pong game. The integrated system employs a multimedia paddle and a tracking device on PC to generate a more sophisticated 6-degree-of-freedom data using either of magnet or optics. The lab-made paddle embeds a Bluetooth module, vibration motor, LED, and mini-speaker. Advantages of this webcam-based game are wireless, robust to electromagnetic interference, and low cost. The game software includes comprehensive physical modeling of most of the parameters of a real ping-pong game. Build up of the overall system is inexpensive and sufficiently accurate for game play. It presents a more functional and realistic feeling in playing computer game compared to existing commercial systems.